Bio

Clinical Focus


  • Orthopaedic Surgery
  • Spine Surgery

Academic Appointments


Administrative Appointments


  • Residency Program Director, Orthopaedic Surgery (2009 - Present)
  • Associate Residency Program Director, Orthopaedic Surgery (2007 - 2009)
  • Resident Selection Commitee, Department of Orthopaedic Surgery, Stanford University School of Medicine (2004 - Present)
  • Chief of the Education Commitee, Department of Orthopaedic Surgery, Stanford University School of Medicine (2005 - Present)

Honors & Awards


  • AOA-JOA Traveling Fellowship, American Orthopaedic Association (2010)
  • Saul Halpern, MD Orthopaedic Educator Award, Department of Orthopaedic Surgery, Stanford University Medical Center (2005)
  • Timothy J. Bray Trauma Award, UC Davis Department of Orthopaedic Surgery (2003)
  • Cum laude, Harvard Medical School (1997)
  • Highest Distinction, UC Berkeley (1993)

Professional Education


  • Fellowship:Washington University in St Louis (2004) MO
  • Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (2006)
  • Residency:UC Davis Medical Center (2003) CA
  • Internship:UC Davis Medical Center (1999) CA
  • Medical Education:Harvard Medical School (1998) MA
  • BA, UC Berkeley, Neurobiology (1993)

Research & Scholarship

Current Research and Scholarly Interests


Dr. Cheng's research interests lie in the biologic enhancement of spinal fusions, molecular techniques of intervertebral disc regeneration, and techniques of spinal instrumentation. For more information, please go to http://www.ivanchengmd.com.

Teaching

2013-14 Courses


Publications

Journal Articles


  • Complications: a critical component of patient outcome. spine journal Stauff, M. P., Cheng, I. 2013; 13 (6): 625-627

    Abstract

    COMMENTARY ON: Mannion AF, Fekete TF, O'Riordan D, et al. The assessment of complications after spine surgery: time for a paradigm shift? Spine J 2013;13:615-24 (in this issue).

    View details for DOI 10.1016/j.spinee.2013.03.008

    View details for PubMedID 23578984

  • Thoracolumbar fracture dislocation sustained during childbirth in a patient with ankylosing spondylitis SPINE JOURNAL Mayle, R. E., Cheng, I., Carragee, E. J. 2012; 12 (11): E5-E8

    Abstract

    Ankylosing spondylitis (AS) is a major subtype of the spondyloarthropathies. Uncoupling of bone formation and resorption along with ectopic ossification of paraspinal soft-tissue structures alters the biomechanics of the spine and leads to an increased susceptibility to fracture.To report on a thoracolumbar fracture dislocation sustained in a 33-year-old Gravida 2/Para 2 woman, which occurred during labor. Although there are several reports in the literature of thoracolumbar fracture dislocations sustained in patients with AS, none have been reported during childbirth.Case report.An elevated suspicion for injury should be maintained when patients with AS present with back or neck pain even without a history of significant trauma.

    View details for DOI 10.1016/j.spinee.2012.10.012

    View details for Web of Science ID 000311807300002

    View details for PubMedID 23199410

  • Functional assessment of the acute local and distal transplantation of human neural stem cells after spinal cord injury SPINE JOURNAL Cheng, I., Mayle, R. E., Cox, C. A., Park, D. Y., Smith, R. L., Corcoran-Schwartz, I., Ponnusamy, K. E., Oshtory, R., Smuck, M. W., Mitra, R., Kharazi, A. I., Carragee, E. J. 2012; 12 (11): 1040-1044

    Abstract

    Spinal cord injury can lead to severe functional impairments secondary to axonal damage, neuronal loss, and demyelination. The injured spinal cord has limited regrowth of damaged axons. Treatment remains controversial, given inconsistent functional improvement. Previous studies demonstrated functional recovery of rats with spinal cord contusion after transplantation of rat fetal neural stem cells.We hypothesized that acute transplantation of human fetal neural stem cells (hNSCs) both locally at the injury site as well as distally via intrathecal injection would lead to improved functional recovery compared with controls.Twenty-four adult female Long-Evans hooded rats were randomized into four groups with six animals in each group: two experimental and two control. Functional assessment was measured after injury and then weekly for 6 weeks using the Basso, Beattie, and Bresnahan Locomotor Rating Score. Data were analyzed using two-sample t test and linear mixed-effects model analysis.Posterior exposure and laminectomy at T10 level was used. Moderate spinal cord contusion was induced by the Multicenter Animal Spinal Cord Injury Study Impactor with 10-g weight dropped from a height of 25 mm. Experimental subjects received either a subdural injection of hNSCs locally at the injury site or intrathecal injection of hNSCs through a separate distal laminotomy. Controls received control media injection either locally or distally.Statistically significant functional improvement was observed in local or distal hNSCs subjects versus controls (p=.034 and 0.016, respectively). No significant difference was seen between local or distal hNSC subjects (p=.66).Acute local and distal transplantation of hNSCs into the contused spinal cord led to significant functional recovery in the rat model. No statistical difference was found between the two techniques.

    View details for DOI 10.1016/j.spinee.2012.09.005

    View details for Web of Science ID 000311807300013

    View details for PubMedID 23063425

  • Postoperative spinal deformity after treatment of intracanal spine lesions SPINE JOURNAL Joaquim, A. F., Cheng, I., Patel, A. A. 2012; 12 (11): 1067-1074

    Abstract

    Surgical treatment of intracanal (both intramedullary and extramedullary) spine lesions requires posterior decompressive techniques in nearly all instances. Postoperative spinal deformities, most notably sagittal and coronal decompensation, are of significant concern for both the patient and the spinal surgeon.To review and define principles and features of spinal deformities after posterior spinal decompression for intracanal spinal lesions, and to define patients who may benefit from the concomitant spinal fusion.A systematic review of MEDLINE was conducted, including articles published between 1980 and 2011. Articles related to spinal deformities after posterior decompression for the treatment of intracanal spine lesions were identified.Ten articles met all inclusion and exclusion criteria. All were case series with limited evidence (Level IV). Many risk factors to deformity were implied but with limited evidence. Young age was the most commonly identified risk in these articles.Spinal deformity after posterior decompression is a common complication, most notably in children and young adults, after the removal of intramedullary tumors. Many risk factors have been implied to increase the postoperative development of spinal deformity, including young age, laminectomy extension, preoperative deformity, and extensive facet resection, among others. However, there is a lack of high-quality evidence to propose an algorithm for treatment or preventive measures. New studies with larger series of patients and standardized clinical outcomes are necessary to establish optimal treatment protocols.

    View details for DOI 10.1016/j.spinee.2012.09.054

    View details for Web of Science ID 000311807300017

    View details for PubMedID 23116818

  • Full-endoscopic interlaminar approach for the surgical treatment of lumbar disc herniation: the causes and prophylaxis of conversion to open ARCHIVES OF ORTHOPAEDIC AND TRAUMA SURGERY Wang, B., Lu, G., Liu, W., Cheng, I., Patel, A. A. 2012; 132 (11): 1531-1538

    Abstract

    Retrospective case series.To analyze the causes of conversion to open for the surgical treatment of lumbar disc herniation with use of full endoscopic (FE) technique, and prophylaxis of conversion to open also proposed.50 patients with lumbar disc herniation underwent discectomy using unilateral portal FE interlaminar approach collected from August 2008 to August 2010. All FE operations were performed under general anesthesia and endotracheal intubation. According to the level incision of the ligament flavum, the starting point of nerve root at the dura under endoscopic view was classified as: Type I (starting point of the nerve root was higher than the incision) and Type II (the starting point of nerve root was lower than the incision). The causes and effective prophylactic measurements for cases of conversion to open were analyzed.There were 47 cases classified as Type I for a rate of 94 %, and Type II in 3 cases for a rate of 6 %. Five cases were converted to open surgery, and the conversion rate was 10 %. There were three males and two females with a mean age of 36.2 (29-44) years, the average duration of symptoms was 58.4 (35-105) days. The level was L5-S1 in four cases and L4-5 in one, lateral extrusion in three cases, paracentral extrusion in one, and sequestration in one. Leg pain resolved in three cases and improved in two after open surgery. Of five cases of conversion to open, misplacement of the working portal occurred in one case (Type I). Difficult dissection of nerve root and hemostasis resulting in open conversion occurred in one case (Type II); this patient sustained a dural injury. The nerve root could not be exposed in three cases (Type II), the FE changed to open finally. During the open procedure with Type II, we found that the location of origin of the nerve root was caudal to the inferior laminar edge. Therefore, partial removal of bony structures along lateral recess was necessary in order to visualize the nerve root.Misplacement of working portal during the exposure of the ligament flavum and difficulty in indentifying anatomy are potential causes for conversion to open in the initial adoption of FE technique. However, uncommon conditions such as variation of the nerve root origin can also result in conversion to open in experienced hands. Endoscopic experience, proper patient selection and specific radiographic examination are needed to obtain optimal outcomes using a full endoscopic technique for microdiscectomies.

    View details for DOI 10.1007/s00402-012-1581-9

    View details for Web of Science ID 000310086700002

    View details for PubMedID 22763864

  • A biologic without guidelines: the YODA project and the future of bone morphogenetic protein-2 research SPINE JOURNAL Carragee, E. J., Baker, R. M., Benzel, E. C., Bigos, S. J., Cheng, I., Corbin, T. P., Deyo, R. A., Hurwitz, E. L., Jarvik, J. G., Kang, J. D., Lurie, J. D., Mroz, T. E., Oener, F. C., Peul, W. C., Rainville, J., Ratliff, J. K., Rihn, J. A., Rothman, D. J., Schoene, M. L., Spengler, D. M., Weiner, B. K. 2012; 12 (10): 877-880

    View details for DOI 10.1016/j.spinee.2012.11.002

    View details for Web of Science ID 000311684600004

    View details for PubMedID 23199819

  • Foot and Ankle Questions on the Orthopaedic In-Training Examination: Analysis of Content, Reference, and Performance ORTHOPEDICS Barr, C. R., Cheng, I., Chou, L. B., Hunt, K. J. 2012; 35 (6): E880-E888

    Abstract

    The purpose of this study was to provide a comprehensive analysis of the Orthopaedic In-Training Examination's (OITE's) questions, question sources, and resident performance over the course of residency training.The authors analyzed all OITE questions pertaining to foot and ankle surgery between 2006 and 2010. Recorded data included the topic and area tested, imaging modality used, tested treatment method, taxonomic classification, cited references, and resident performance scores. Foot- and ankle-related questions made up 13.9% (186/1341) of the OITE questions. Thirteen general topic areas were identified, with the most common being foot and ankle trauma, the pediatric foot, and foot and ankle deformity. Imaging modalities were tested in approximately half of the questions. Knowledge of treatment modalities was required in 58.1% (108/186) of the questions. Recall-type questions were the most common. Trends existed in the recommended references, with 2 journals and 1 textbook being commonly and consistently cited: Foot and Ankle International, The Journal of Bone and Joint Surgery American Volume, and Surgery of the Foot and Ankle, respectively. Resident performance scores increased with each successive level of training.An understanding of the topics and resources used for OITE foot and ankle questions is an important aid in creating or improving residency programs' foot and ankle education curricula. With knowledge of question content, source, and resident performance, education can be optimized toward efficient learning and improved scores on this section of the examination.

    View details for DOI 10.3928/01477447-20120525-28

    View details for Web of Science ID 000305430300016

    View details for PubMedID 22691661

  • Arachnoid ossificans containing metaplastic hematopoietic marrow resulting in diffuse thoracic intrathecal cysts and severe myelopathy. European spine journal Abrams, J., Li, G., Mindea, S. A., Haynes, C. M., Cheng, I. 2012; 21: S436-40

    Abstract

    To present a rare case of multiple compressive thoracic intradural cysts with pathologic arachnoid ossification, review the literature and present the surgical options. Few reports have identified the existence of arachnoid calcifications and intrathecal cysts causing progressive myelopathy. The literature regarding each of these pathologies is limited to case reports. Their clinical significance is not well studied, although known to cause neurologic sequelae.An 81-year-old female clinically presents with rapidly progressive myelopathy. Pre-operative magnetic resonance imaging identified multiple compressive thoracic intrathecal cysts. Surgical exploration and decompression of these cysts identified calcified plaques within the arachnoid. Histopathologic examination revealed fibrocalcific tissue undergoing ossification with bone marrow elements.Due to progressive myelopathy, the thoracic cysts were decompressed and calcified plaques were excised, once identified intra-operatively.On last examination, the patient's neurologic status had not improved, but had stabilized. The rate of neurologic improvement from excision and decompression is variable, but it may still be warranted in the face of progressive neurologic deficits.

    View details for DOI 10.1007/s00586-011-2005-1

    View details for PubMedID 21892775

  • Morbidity and Mortality of C2 Fractures in the Elderly: Surgery and Conservative Treatment NEUROSURGERY Chen, Y., Boakye, M., Arrigo, R. T., Kalanithi, P. S., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Park, J. 2012; 70 (5): 1055-1059

    Abstract

    Closed C2 fractures commonly occur after falls or other trauma in the elderly and are associated with significant morbidity and mortality. Controversy exists as to best treatment practices for these patients.To compare outcomes for elderly patients with closed C2 fractures by treatment modality.We retrospectively reviewed 28 surgically and 28 nonsurgically treated cases of closed C2 fractures without spinal cord injury in patients aged 65 years of age or older treated at Stanford Hospital between January 2000 and July 2010. Comorbidities, fracture characteristics, and treatment details were recorded; primary outcomes were 30-day mortality and complication rates; secondary outcomes were length of hospital stay and long-term survival.Surgically treated patients tended to have more severe fractures with larger displacement. Charlson comorbidity scores were similar in both groups. Thirty-day mortality was 3.6% in the surgical group and 7.1% in the nonsurgical group, and the 30-day complication rates were 17.9% and 25.0%, respectively; these differences were not statistically significant. Surgical patients had significantly longer lengths of hospital stay than nonsurgical patients (11.8 days vs 4.4 days). Long-term median survival was not significantly different between groups.The 30-day mortality and complication rates in surgically and nonsurgically treated patients were comparable. Elderly patients faced relatively high morbidity and mortality regardless of treatment modality; thus, age alone does not appear to be a contraindication to surgical fixation of C2 fractures.

    View details for DOI 10.1227/NEU.0b013e3182446742

    View details for Web of Science ID 000303390400013

    View details for PubMedID 22157549

  • Commentary: Spinopelvic parameters-how far have we come? SPINE JOURNAL Cheng, I. 2012; 12 (5): 447-448

    Abstract

    COMMENTARY ON: Vrtovec T, Janssen MMA, Likar B. A review of methods for evaluating the quantitative parameters of sagittal pelvic alignment. Spine J 2012;12:433-46 (in this issue).

    View details for DOI 10.1016/j.spinee.2012.03.007

    View details for Web of Science ID 000305298300013

    View details for PubMedID 22698152

  • Anterior debridement and reconstruction via thoracoscopy-assisted mini-open approach for the treatment of thoracic spinal tuberculosis: minimum 5-year follow-up EUROPEAN SPINE JOURNAL Lu, G., Wang, B., Li, J., Liu, W., Cheng, I. 2012; 21 (3): 463-469

    Abstract

    Video-assisted thoracoscopic surgery (VATS) has been developed for surgical treatment of thoracic spinal tuberculosis to overcome the problems associated with a formal thoracotomy. VATS, however, is technically demanding with a difficult learning curve.We conducted a retrospective long-term follow-up study of anterior debridement and reconstruction via a thoracoscopy-assisted mini-open approach for the surgical treatment of thoracic spinal tuberculosis. There were 50 patients collected with mean age 38.3 years with thoracic spinal tuberculosis.The average operative time was 210 min (range 170-300 min), the average blood loss during operation was 550 ml (range 300-1,000 ml), and the mean chest drainage duration was 3.5 days (3-5 days). Complications occurred in 17 patients (34%). The mean follow-up was 6.5 years. There was statistically difference in VAS 3 months after surgery compared to preoperatively (P<0.001), as well as final follow-up compared to 3 months post-op (P<0.001). In patients with minor pulmonary impairment as measured by pulmonary function testing, 15 improved to normal and 5 had no change. In patients with moderate pulmonary impairment, 6 improved to normal and 2 improved to minor impairment at final follow-up. Neurological improvement of one to three grades had occurred in 26 patients by final follow-up. There was statistically difference in kyphotic angle 3 months after surgery compared to preoperatively (P<0.05), as well as final follow-up compared to 3 months post-op (P<0.001). The average correction rate of kyphotic angle was 38.7% and the loss of correction rate was 1.3% at final follow-up. No recurrent tuberculosis was found.Thoracoscopy-assisted mini-open approach can provide a simple, safe, and practical treatment option with minimal invasiveness in cases of thoracic spinal tuberculosis. Successful clinical and radiographic outcomes can be achieved via anterior debridement and reconstruction at long-term follow-up.

    View details for DOI 10.1007/s00586-011-2038-5

    View details for Web of Science ID 000301441100013

    View details for PubMedID 21997276

  • Anterior Radical Debridement and Reconstruction Using Titanium Mesh Cage for the Surgical Treatment of Thoracic and Thoracolumbar Spinal Tuberculosis: Minimium Five-Year Follow-Up TURKISH NEUROSURGERY Wang, B., Li, G., Liu, W., Cheng, I. 2011; 21 (4): 575-581
  • Anterior endoscopically assisted transcervical reconstruction of the upper cervical spine EUROPEAN SPINE JOURNAL Wang, B., Lu, G., Deng, Y., Liu, W., Li, J., Cheng, I. 2011; 20 (9): 1526-1532

    Abstract

    Anterior decompression and/or reconstruction can be an effective method for the surgical treatment of ventral spinal cord compression in the upper cervical spine. Options for traditional surgical approaches include transoral, transnasal, and extraoral. The risk and complex anatomy with the aforementioned approaches induces surgeons to use the transcervical route to expose the upper cervical spine. A traditional transcervical approach, however, carries the disadvantages of a deep operative field and steep trajectory. We performed a new endoscopically assisted method of anterior reconstruction for the treatment of ventral lesions in upper cervical spine. Six patients were treated from January 2005 to December 2007. Among those six patients, three patients were diagnosed with fixed atlantoaxial dislocations, two with plasmacytomas, and one with a giant cell tumor. All patients were treated by combined endoscopically assisted anterior reconstruction and posterior fusion. One patient with a fixed atlantoaxial dislocation sustained a cerebrospinal fluid leak in the immediate postoperative period, which spontaneously resolved 7 days after surgery. None of the patients had any neurologic deterioration following surgery, nor did any require admission to the intensive care unit for any reason. At the final follow-up, all patients were found to have evidence of a successful clinical outcomes and radiographic fusion. There were no implant failures or radiographic signs of implant migration or loosening. In conclusion, this study demonstrates that an anterior transcervical decompression using endoscopic visualization combined with a posterior arthodesis can achieve good clinical and radiographic outcomes.

    View details for DOI 10.1007/s00586-011-1770-1

    View details for Web of Science ID 000294706700016

    View details for PubMedID 21416277

  • Charlson Score is a Robust Predictor of 30-Day Complications Following Spinal Metastasis Surgery SPINE Arrigo, R. T., Kalanithi, P., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Boakye, M., Park, J. 2011; 36 (19): E1274-E1280

    Abstract

    Retrospective chart review.To identify predictors of 30-day complications after the surgical treatment of spinal metastasis.Surgical treatment of spinal metastasis is considered palliative with the aim of reducing or delaying neurologic deficit. Postoperative complication rates as high as 39% have been reported in the literature. Complications may impact patient quality of life and increase costs; therefore, an understanding of which preoperative variables best predict 30-day complications will help risk-stratify patients and guide therapeutic decision making and informed consent.We retrospectively reviewed 200 cases of spinal metastasis surgically treated at Stanford Hospital between 1999 and 2009. Multiple logistic regression was performed to determine which preoperative variables were independent predictors of 30-day complications.Sixty-eight patients (34%) experienced one or more complications within 30 days of surgery. The most common complications were respiratory failure, venous thromboembolism, and pneumonia. On multivariate analysis, Charlson Comorbidity Index score was the most significant predictor of 30-day complications. Patients with a Charlson score of two or greater had over five times the odds of a 30-day complication as patients with a score of zero or one.After adjusting for demographic, oncologic, neurologic, operative, and health factors, Charlson score was the most robust predictor of 30-day complications. A Charlson score of two or greater should be considered a surgical risk factor for 30-day complications, and should be used to risk-stratify surgical candidates. If complications are anticipated, medical staff can prepare in advance, for instance, scheduling aggressive ICU care to monitor for and treat complications. Finally, Charlson score should be controlled for in future spinal metastasis outcomes studies and compared to other comorbidity assessment tools.

    View details for DOI 10.1097/BRS.0b013e318206cda3

    View details for Web of Science ID 000294207500005

    View details for PubMedID 21358481

  • Comparison of perioperative parameters and complications observed in the anterior exposure of the lumbar spine by a spine surgeon with and without the assistance of an access surgeon SPINE JOURNAL Smith, M. W., Rahn, K. A., Shugart, R. M., Belschner, C. D., Stout, K. S., Cheng, I. 2011; 11 (5): 389-394

    Abstract

    The anterior approach to the spine is becoming an increasingly important avenue to treat spine conditions. Most of the literature reporting on the exposure uses an access surgeon assisting the spine surgeon to expose and prepare the spine for implant.To compare perioperative parameters and complications in anterior lumbar spine surgery with the exposure performed either by a spine surgeon or a general surgeon.A retrospective cohort study comparing perioperative parameters and complications of anterior lumbar spine surgery.A retrospective review was completed on 96 consecutive patients who underwent anterior spine surgery between Levels L3 and S1 from 1995 to 2008. Patient and surgery characteristics including demographics, comorbidities, perioperative parameters, and complications were logged. In the first 56 consecutive patients, a general surgeon completed the exposure, with an additional patient who later had the exposure performed by a general surgeon because of extensive prior abdominal surgeries. In the next 39 patients, the orthopedic surgeon completed the exposure.When the operation was performed solely by a spine surgeon, the estimated blood loss, operative time, and hospital stay was 204 mL, 2.80 hours, and 3.5 days, respectively. In the procedures completed with the aid of a general surgeon, it was found that the same parameters were 420 mL, 3.93 hours, and 4.7 days, respectively, and statistically significantly less in the group without the assistance of the general surgeon (p=.0007, p=.0003, and p=.0006, respectively). Fewer complications also were observed in that group (p<.00001). The most common complication was an ileus. Major complications including retrograde ejaculation, iliac vein bleeding, peritoneal rent requiring repair, dyspareunia, or scrotal/penile swelling were only observed in the group with the assistance of the general surgeon.This study indicated that a spine surgeon can successfully and safely carry out the anterior exposure to the spine without the aid of an access surgeon.

    View details for DOI 10.1016/j.spinee.2011.03.014

    View details for Web of Science ID 000290396800006

    View details for PubMedID 21498131

  • Predictors of Survival After Surgical Treatment of Spinal Metastasis NEUROSURGERY Arrigo, R. T., Kalanithi, P., Cheng, I., Alamin, T., Carragee, E. J., Mindea, S. A., Park, J., Boakye, M. 2011; 68 (3): 674-681

    Abstract

    Surgery for spinal metastasis is a palliative treatment aimed at improving patient quality of life by alleviating pain and reversing or delaying neurologic dysfunction, but with a mean survival time of less than 1 year and significant complication rates, appropriate patient selection is crucial.To identify the most significant prognostic variables of survival after surgery for spinal metastasis.Chart review was performed on 200 surgically treated spinal metastasis patients at Stanford Hospital between 1999 and 2009. Survival analysis was performed and variables entered into a Cox proportional hazards model to determine their significance.Median overall survival was 8.0 months, with a 30-day mortality rate of 3.0% and a 30-day complication rate of 34.0%. A Cox proportional hazards model showed radiosensitivity of the tumor (hazard ratio: 2.557, P<.001), preoperative ambulatory status (hazard ratio: 2.355, P=.0001), and Charlson Comorbidity Index (hazard ratio: 2.955, P<.01) to be significant predictors of survival. Breast cancer had the best prognosis (median survival, 27.1 months), whereas gastrointestinal tumors had the worst (median survival, 2.66 months).We identified the Charlson Comorbidity Index score as one of the strongest predictors of survival after surgery for spinal metastasis. We confirmed previous findings that radiosensitivity of the tumor and ambulatory status are significant predictors of survival.

    View details for DOI 10.1227/NEU.0b013e318207780c

    View details for Web of Science ID 000287242300036

    View details for PubMedID 21311295

  • Pregabalin as a Neuroprotector after Spinal Cord Injury in Rats: Biochemical Analysis and Effect on Glial Cells JOURNAL OF KOREAN MEDICAL SCIENCE Ha, K., Carragee, E., Cheng, I., Kwon, S., Kim, Y. 2011; 26 (3): 404-411

    Abstract

    As one of trials on neuroprotection after spinal cord injury, we used pregabalin. After spinal cord injury (SCI) in rats using contusion model, we observed the effect of pregabalin compared to that of the control and the methylprednisolone treated rats. We observed locomotor improvement of paralyzed hindlimb and body weight changes for clinical evaluation and caspase-3, bcl-2, and p38 MAPK expressions using western blotting. On histopathological analysis, we also evaluated reactive proliferation of glial cells. We were able to observe pregabalin's effectiveness as a neuroprotector after SCI in terms of the clinical indicators and the laboratory findings. The caspase-3 and phosphorylated p38 MAPK expressions of the pregabalin group were lower than those of the control group (statistically significant with caspase-3). Bcl-2 showed no significant difference between the control group and the treated groups. On the histopathological analysis, pregabalin treatment demonstrated less proliferation of the microglia and astrocytes. With this animal study, we were able to demonstrate reproducible results of pregabalin's neuroprotection effect. Diminished production of caspase-3 and phosphorylated p38 MAPK and as well as decreased proliferation of astrocytes were seen with the administration of pregabalin. This influence on spinal cord injury might be a possible approach for achieving neuroprotection following central nervous system trauma including spinal cord injury.

    View details for DOI 10.3346/jkms.2011.26.3.404

    View details for Web of Science ID 000288838400014

    View details for PubMedID 21394310

  • Kyphectomy in the treatment of patients with myelomeningocele SPINE JOURNAL Samagh, S. P., Cheng, I., Elzik, M., Kondrashov, D. G., Rinsky, L. A. 2011; 11 (3): E5-E11

    Abstract

    Myelomeningocele kyphosis is a complex disorder that usually requires surgical intervention. Many complications can occur as a result of this disorder and its treatment, but only surgical correction offers the possibility of restoring spinal alignment.The purpose of this retrospective study was to summarize the surgical results, complications, and short-term and midterm outcomes for surgical correction of severe kyphosis using a consistent surgical technique.This was a retrospective review of our database of pediatric patients with myelomeningocele and lumbar kyphosis who underwent kyphectomy with the use of the Warner and Fackler technique.Eleven pediatric kyphectomy cases performed by a single surgeon from 1984 to 2009 were reviewed.Outcome measures include imaging, kyphotic angle measurement, and physical examination.Patients underwent the Warner and Fackler technique of posterior-only kyphectomy and bayonet-shaped anterior sacral fixation.The mean extent of kyphosis was 115.6° (range, 77-176°) preoperatively with a correction to 13.0° (range, 0-32°) postoperatively, and a reduction with an average of 102.6° (range, 65-160°), for an 88.7% correction. On an average, 2.0 (range, 1-6) vertebrae were resected. Immediately postoperatively and at follow-up, with an average of 67.2 months (range, 8-222 months), the average kyphosis angle was 13.0° (range, 0-32°). All patients undergoing the procedure were unable to lie supine preoperatively. All patients postoperatively could lie in the supine position. The functional outcome in patients and caretakers was rated very favorably because all patients and caretakers who provided feedback (9 of 11) reported that they were satisfied with the procedure and would undergo the procedure again if given the choice.This technique has become the most effective surgical reconstruction in myelomeningocele kyphosis. Although significant complications can occur during and after the procedure, most patients had satisfactory postoperative outcomes and restoration of sagittal balance with high patient and parent satisfaction.

    View details for DOI 10.1016/j.spinee.2011.01.020

    View details for Web of Science ID 000288013200002

    View details for PubMedID 21377598

  • An evaluation of the learning curve for a complex surgical technique: the full endoscopic interlaminar approach for lumbar disc herniations SPINE JOURNAL Wang, B., Lue, G., Patel, A. A., Ren, P., Cheng, I. 2011; 11 (2): 122-130
  • Massive spontaneous epidural hematoma in a high-level swimmer: a case report. journal of bone and joint surgery. American volume Fleager, K., Lee, A., Cheng, I., Hou, L., Ryu, S., Boakye, M. 2010; 92 (17): 2843-2846

    View details for DOI 10.2106/JBJS.I.01604

    View details for PubMedID 21123615

  • Biomechanical Analysis of Derotation of the Thoracic Spine Using Pedicle Screws SPINE Cheng, I., Hay, D., Iezza, A., Lindsey, D., Lenke, L. G. 2010; 35 (10): 1039-1043

    Abstract

    Biomechanical analysis of derotational load-to-failure of pedicle screw (PS) instrumentation in cadaveric thoracic spinal segments.To investigate the derotational torque that can be applied to the thoracic spine through different linked constructs and evaluate the modes of failure.Thoracic derotation with PSs has been shown to provide better 3 plane correction than other methods but the effects of linked PS constructs has not been studied.Four groups of thoracic segments with different PS constructs were loaded to failure with a rotational torque applied to the construct to simulate the left to right derotational force applied to a typical idiopathic dextrorotary thoracic scoliosis curve. Single screw T4 segments instrumented on the medial (group 1M) and lateral (group 1L) sides, bilaterally-linked T5 segments (group 2), unilaterally-linked T6-T9 segments on the medial (group 3M) and lateral (group 3L) sides, and quadrangularly-linked T6-T9 segments (group 4) were loaded with MTS machine in a simulated thoracic derotation model.Single T4 PSs on the medial and lateral sides failed at 4.0 +/- 1.4 Nm (group 1M) and 6.1 +/- 2.5 Nm (group 1L), respectively. Bilaterally-linked T5 screws failed at 11.9 +/- 3.1 Nm (group 2). Unilaterally linked T6-T9 PS constructs on the medial and lateral sides failed at 21.2 +/- 7.5 Nm (group 3M) and 17.9 +/- 11.1 Nm (group 3L), respectively. Quadrangularly-linked PSs failed at 42.5 +/- 14.5 Nm (group 4). CONCLUSION.: A near linear increase in relative torque applied before failure was found with each additional PS linked. Linked constructs allow for significantly greater torque with less risk of PS breach of the spinal canal.

    View details for DOI 10.1097/BRS.0b013e3181d85ec8

    View details for Web of Science ID 000277224800005

    View details for PubMedID 20393385

  • Minimum acceptable outcomes after lumbar spinal fusion SPINE JOURNAL Carragee, E. J., Cheng, I. 2010; 10 (4): 313-320

    Abstract

    Defining success after spinal surgery remains problematic. The minimal clinically important difference (MCID) in pain or functional outcomes is a common metric often calculated independent of perceived risk and morbidity, which is an important consideration in large procedures such as spinal fusion and instrumentation.The purpose of this study was to describe a method of assessing treatment success based on prospective, patient-reported "minimum acceptable" outcome for which they would undergo a procedure. These goals can then be compared at follow-up to gauge how frequently patient goals are met and determine correlation with patient satisfaction.This is a clinical descriptive study of the patient-reported minimum acceptable outcomes for spinal fusion surgery.Minimum acceptable outcomes were determined by patients on preoperatively administered standard questionnaires regarding ultimate pain intensity, functional outcome (Oswestry Disability Index [ODI]), medication usage, and work status. Satisfaction with outcomes was assessed at 2-year follow-up.One hundred sixty-five consecutive patients undergoing lumbar fusion for either isthmic spondylolisthesis or disc degeneration were asked to preoperatively define on standard questionnaires their minimum acceptable outcomes after surgery. Two-year outcomes and satisfaction were subsequently reported and compared with the preoperatively determined minimum acceptable outcomes.Both the spondylolisthesis and the degenerative disc disease (DDD) groups reported that a high degree of improvement was the minimum acceptable threshold for considering spinal fusion. A large majority indicated that the minimum acceptable outcomes included at least a decrease in pain intensity to 3/10 or less, an improvement in ODI of 20 or more, discontinuing opioid medications, and return to some occupational activity. Achieving the minimum acceptable outcome was strongly associated with satisfaction at 2 years after surgery. Patients with compensation claims, psychological distress, and other psychosocial stressors were more likely to report satisfaction in the absence of achieving their minimum acceptable outcome.Patients with spondylolisthesis and DDD both have relatively high minimum acceptable outcomes for spinal fusion. In these cohorts, few subjects considered more commonly proposed MCIDs for pain and function as an acceptable outcome and report that they would not have surgery if they did not expect to achieve more than those marginal improvements. Although there was good concordance between achieving the minimum acceptable outcomes and ultimate satisfaction, patients with significant psychosocial factors (compensation claims, psychological distress, and others) are less likely to associate satisfaction with outcomes with actually achieving these improvements.

    View details for DOI 10.1016/j.spinee.2010.02.001

    View details for Web of Science ID 000276971600006

    View details for PubMedID 20362247

  • Facet Pain in Thoracic Compression Fractures PAIN MEDICINE Mitra, R., Do, H., Alamin, T., Cheng, I. 2010; 11 (11): 1674-1677

    Abstract

    To determine if thoracic facet joints may be a significant secondary pain generator in patients with compression fractures. Traditionally, pain from vertebral compression fractures has been attributed to vertebral body itself. Compression fractures have been shown to increase thoracic kyphosis and thereby increase the thoracic flexion moment; these changes eventually increase the shear stress on the posterior elements.We present a small case series of patients with thoracic compression fractures managed with intra-articular facet injections.Tertiary care academic medical center.Two patients with thoracic compression fractures.The subjects received fluoroscopically guided thoracic facet steroid injections for pain management.Change in verbal analog pain score.Patients with thoracic compression fractures received significant long-lasting relief after receiving fluoroscopically guided intra-articular injections.Facet joints may be abnormally stressed due to the increasing thoracic flexion moment in anterior compression fractures, which may serve as a secondary pain generator; intra-articular facet blocks may be an alternative to vertebroplasty.

    View details for Web of Science ID 000283989800011

    View details for PubMedID 21029349

  • Point of view: spinopelvic parameters in postfusion flatback deformity patients SPINE JOURNAL Cheng, I. 2009; 9 (8): 672-673

    View details for DOI 10.1016/j.spinee.2009.05.011

    View details for Web of Science ID 000268786300009

    View details for PubMedID 19560404

  • TREATMENT OF NECK PAIN Injections and Surgical Interventions: Results of the Bone and Joint Decade 2000-2010 Task Force on Neck Pain and Its Associated Disorders (Reprinted from Spine, vol 33, pg S153-S169, 2008) JOURNAL OF MANIPULATIVE AND PHYSIOLOGICAL THERAPEUTICS Carragee, E. J., Hurwitz, E. L., Cheng, I., Carroll, L. J., Nordin, M., Guzman, J., Peloso, P., Holm, L. W., Cote, P., Hogg-Johnson, S., van der Velde, G., Cassidy, J. D., Haldeman, S. 2009; 32 (2): S176-S193

    Abstract

    Best evidence synthesis.To identify, critically appraise, and synthesize literature from 1980 through 2006 on surgical interventions for neck pain alone or with radicular pain in the absence of serious pathologic disease.There have been no comprehensive systematic literature or evidence-based reviews published on this topic.We systematically searched Medline for literature published from 1980 to 2006 on percutaneous and open surgical interventions for neck pain. Publications on the topic were also solicited from experts in the field. Consensus decisions were made about the scientific merit of each article; those judged to have adequate internal validity were included in our Best Evidence Synthesis.Of the 31,878 articles screened, 1203 studies were relevant to the Neck Pain Task Force mandate and of these, 31 regarding treatment by surgery or injections were accepted as scientifically admissible. Radiofrequency neurotomy, cervical facet injections, cervical fusion and cervical arthroplasty for neck pain without radiculopathy are not supported by current evidence. We found there is support for short-term symptomatic improvement of radicular symptoms with epidural corticosteroids. It is not clear from the evidence that long-term outcomes are improved with the surgical treatment of cervical radiculopathy compared to nonoperative measures. However, relatively rapid and substantial symptomatic relief after surgical treatment seems to be reliably achieved. It is not evident that one open surgical technique is clearly superior to others for radiculopathy. Cervical foramenal or epidural injections are associated with relatively frequent minor adverse events (5%-20%); however, serious adverse events are very uncommon (<1%). After open surgical procedures on the cervical spine, potentially serious acute complications are seen in approximately 4% of patients.Surgical treatment and limited injection procedures for cervical radicular symptoms may be reasonably considered in patients with severe impairments. Percutaneous and open surgical treatment for neck pain alone, without radicular symptoms or clear serious pathology, seems to lack scientific support.

    View details for DOI 10.1016/j.jmpt.2008.11.018

    View details for Web of Science ID 000264208500018

    View details for PubMedID 19251063

  • Retroperitoneal lymphocele after anterior spinal surgery SPINE Patel, A. A., Spiker, W. R., Daubs, M. D., Brodke, D. S., Cheng, I., Glasgow, R. E. 2008; 33 (18): E648-E652

    Abstract

    Case report; Review of Literature.To present an uncommon complication after anterior lumbar surgery as well as a treatment option and a review of the literature.A number of complications have been reported after anterior lumbar surgery. Common complications include vascular, ureteral, and neurologic injuries. The development of a retroperitoneal lymphocele has been previously been described, but details regarding evaluation, diagnosis, and treatment options are lacking in the literature.The case of a single patient with a postoperative retroperitoneal lymphocele was identified and retrospectively reviewed. Permission was obtained from the patient to review and publish this information. A review of literature on lymphoceles and anterior lumbar complications was also performed using PubMed and Ovid databases.A 76-year-old woman underwent anterior interbody fusion from L2-L3-L4-L5, followed by posterior T11-L5 fusion for degenerative scoliosis and spinal stenosis. Six weeks after surgery, she presented with severe abdominal pain, nausea, and emesis. Examination revealed a retroperitoneal lymphocele, which was confirmed after aspiration. The patient was treated with a laparoscopic marsupialization procedure without recurrence. At 12 months, the patient had no further abdominal symptoms, noted improvements in back and leg pain scores, and had stable radiographic findings.Retroperitoneal lymphocele is a rare complication after anterior lumbar interbody fusion. The different diagnosis should include infectious abscess, ureteral injury with urinoma, pancreatic injury with pseudocyst formation, and spinal fluid leak with pseudomeningocele. Diagnosis can be guided by serum and cyst fluid analysis. Although treatment options exist, surgical treatment may provide the most reliable results.

    View details for Web of Science ID 000258592800022

    View details for PubMedID 18708917

  • Chymopapain: a shot from the past. Pain practice Mitra, R., Wedemeyer, M., Cheng, I. 2008; 8 (4): 331-332

    View details for DOI 10.1111/j.1533-2500.2008.00217.x

    View details for PubMedID 18727771

  • Treatment of neck pain - Injections and surgical interventions: Results of the bone and joint decade 2000-2010 task force on neck pain and its associated disorders SPINE Carragee, E. J., Hurwitz, E. L., Cheng, I., Carroll, L. J., Nordin, M., Guzman, J., Peloso, P., Holm, L. W., Cote, P., Hogg-Johnson, S., van der Velde, G., Cassidy, J. D., Haldeman, S. 2008; 33 (4): S153-S169

    Abstract

    Best evidence synthesis.To identify, critically appraise, and synthesize literature from 1980 through 2006 on surgical interventions for neck pain alone or with radicular pain in the absence of serious pathologic disease.There have been no comprehensive systematic literature or evidence-based reviews published on this topic.We systematically searched Medline for literature published from 1980 to 2006 on percutaneous and open surgical interventions for neck pain. Publications on the topic were also solicited from experts in the field. Consensus decisions were made about the scientific merit of each article; those judged to have adequate internal validity were included in our Best Evidence Synthesis.Of the 31,878 articles screened, 1203 studies were relevant to the Neck Pain Task Force mandate and of these, 31 regarding treatment by surgery or injections were accepted as scientifically admissible. Radiofrequency neurotomy, cervical facet injections, cervical fusion and cervical arthroplasty for neck pain without radiculopathy are not supported by current evidence. We found there is support for short-term symptomatic improvement of radicular symptoms with epidural corticosteroids. It is not clear from the evidence that long-term outcomes are improved with the surgical treatment of cervical radiculopathy compared to nonoperative measures. However, relatively rapid and substantial symptomatic relief after surgical treatment seems to be reliably achieved. It is not evident that one open surgical technique is clearly superior to others for radiculopathy. Cervical foramenal or epidural injections are associated with relatively frequent minor adverse events (5%-20%); however, serious adverse events are very uncommon (<1%). After open surgical procedures on the cervical spine, potentially serious acute complications are seen in approximately 4% of patients.Surgical treatment and limited injection procedures for cervical radicular symptoms may be reasonably considered in patients with severe impairments. Percutaneous and open surgical treatment for neck pain alone, without radicular symptoms or clear serious pathology, seems to lack scientific support.

    View details for Web of Science ID 000253739500017

    View details for PubMedID 18204388

  • Interspinous ligament steroid injections for the management of Baastrup's disease: A case report ARCHIVES OF PHYSICAL MEDICINE AND REHABILITATION Mitra, R., Ghazi, U., Kirpalani, D., Cheng, I. 2007; 88 (10): 1353-1356

    Abstract

    Mitra R, Ghazi U, Kirpalani D, Cheng I. Interspinous ligament steroid injections for the management of Baastrup's disease: a case report. Baastrup's disease has been identified as a source of axial low back pain. There has been debate as to the etiology of pain in patients with Baastrup's disease. It has been theorized that the pain may originate from degenerative disk disease and spinal stenosis associated with the disease, whereas some have identified the neoarthrosis between joints and accompanying reactive eburnation as the source of pain. We present a simple case report of an 89-year-old woman with symptomatic Baastrup's disease. The patient underwent a fluoroscopically guided interspinous process injection of 20mg of triamcinolone acetate with local anesthetic. The patient remained pain free for 3 months. The neoarthrosis in Baastrup's disease may be the primary pain generator in cases of Baastrup's disease without significant central canal stenosis.

    View details for DOI 10.1016/j.apmr.2007.05.033

    View details for Web of Science ID 000250161500021

    View details for PubMedID 17908582

  • The role of osteobiologics in spinal deformity NEUROSURGERY CLINICS OF NORTH AMERICA Cheng, I., Oshtory, R., Wildstein, M. S. 2007; 18 (2): 393-?

    Abstract

    Spinal deformity surgery represents one of the most challenging environments in which to achieve bone fusion. High rates of pseudarthroses, limited quantities of available autograft bone, and the potential morbidity of iliac crest harvest have driven a search for bone graft extenders and substitutes. With expanding knowledge of bone biology, the authors review options in spinal fusion with a particular focus on deformity surgery, including the use of autograft, allograft, demineralized bone matrix, ceramics, and bone morphogenetic proteins.

    View details for DOI 10.1016/j.nec.2007.01.002

    View details for Web of Science ID 000247680600025

    View details for PubMedID 17556142

  • Posterior cervical spine surgery for radiculopathy NEUROSURGERY Riew, K. D., Cheng, I., Pimenta, L., Taylor, B. 2007; 60 (1): 57-63
  • Posterior cervical spine surgery for radiculopathy. Neurosurgery Riew, K. D., Cheng, I., Pimenta, L., Taylor, B. 2007; 60 (1): S57-63

    Abstract

    It is now common knowledge that cervical radiculopathy, frequently caused by disc herniation and/or degeneration, will often improve without surgical intervention. Only a small percentage of patients with the severity of symptoms necessitate surgical treatment. Surgery for radiculopathy is indicated for motor weakness, progressive neurological deficits, and progressive symptoms that do not improve with nonoperative treatment. Advantages and disadvantages exist for both ventral and dorsal approaches in the surgical treatment of cervical radiculopathy. Indications and results for dorsal nerve root decompression are discussed, and a review of our preferred techniques, including use of minimally invasive technology, is presented.

    View details for PubMedID 17204887

  • Does minor trauma cause serious low back illness? SPINE Carragee, E., Alamin, T., Cheng, I., Franklin, T., Hurwitz, E. 2006; 31 (25): 2942-2949

    Abstract

    Prospective, 5-year, cohort study of working subjects.To assess whether the occurrence of common minor trauma events affects the risk of developing serious low back pain (LBP) and LBP disability in subjects with and without degenerative changes to the lumbar spine.Although some theories suggest that minor traumatic events in combination with preexisting degenerative changes commonly cause significant structural injury to spinal segments and serious LBP illness, no prospective data exist on the relationship of minor trauma, detailed structural changes, and outcome measures of serious LBP episodes and occupational disability.Two hundred subjects without clinical LBP problems were recruited, and underwent baseline clinical and imaging studies. Every 6 months, subjects completed a scripted, algorithm-based interview assessing interval back pain episodes, severity, medical treatment, occupational disability, and the subject's perceived relation of this LBP episode to any preceding event. If a serious LBP episode clinically required a new magnetic resonance examination, the follow-up imaging was obtained and compared to baseline for interval changes.There was no association of minor trauma to adverse LBP events. For each 6-month study interval, the risk of developing a serious LBP episode was 2.1% unassociated with minor trauma and 2.4% following minor trauma (P = 0.59). Neither the frequency of minor trauma events nor the reported severity of the event correlated with adverse outcomes. Subjects with advanced structural findings were not more likely to become symptomatic with minor trauma events than with spontaneously evolving LBP episodes. Follow-up magnetic resonance imaging evaluating new serious LBP illness rarely revealed new clinically significant findings. Age and sex-adjusted prediction models, including abnormal psychometric testing, smoking, and compensation issues, accurately identified 80% of serious LBP events and 93% of LBP disability events.In this study cohort, minor trauma does not appear to increase the risk of serious LBP episodes or disability. The vast majority of incident-adverse LBP events may be predicted not by structural findings or minor trauma but by a small set of demographic and behavioral variables.

    View details for Web of Science ID 000242576200009

    View details for PubMedID 17139225

  • Are first-time episodes of serious LBP associated with new MRI findings? spine journal Carragee, E., Alamin, T., Cheng, I., Franklin, T., van den Haak, E., Hurwitz, E. 2006; 6 (6): 624-635

    Abstract

    Magnetic resonance (MR) imaging is frequently used to evaluate first-time episodes of serious low back pain (LBP). Common degenerative findings are often interpreted as recent developments and the probable anatomic cause of the new symptoms. To date no prospective study has established a baseline MR status of the lumbar spine in subjects without significant LBP problems and prospectively surveyed these subjects for acute changes shortly after new and serious LBP episodes. This method can identify new versus old MR findings possibly associated with the acute symptomatic episode.To determine if new and serious episodes of LBP are associated with new and relevant findings on MRI.Prospective observational study with baseline and post-LBP MRI monitoring of 200 subjects over 5 years.Clinical outcomes: LBP intensity (visual analogue scale), Oswestry Disability Index, and work loss. MRI outcomes: disc degeneration, herniation, annular fissures, end plate changes, facet arthrosis, canal stenosis, spondylolisthesis, and root impingement.200 subjects with a lifetime history of no significant LBP problems, and a high risk for new LBP episodes were studied at baseline with physical examination, plain radiographs, and MR imaging. Subjects were followed every 6 months for 5 years with a detailed telephone interview. Subjects with a new severe LBP episode (LBP>or=6/10,>1 week) were assessed for new diagnostic tests. New MR imaging, taken within 6 to 12 weeks of the start of a new LBP episode, was compared with baseline (asymptomatic) images. Two independent and blinded readers evaluated each baseline and follow-up study.During the 5-year observation period of 200 subjects, 51 (25%) subjects were evaluated with a lumbar MRI for clinically serious LBP episodes, and 3/51 (6%) had a primary radicular complaint. These 51 subjects had 67 MR scans. Of 51 subjects, 43 (84%) had either unchanged MR or showed regression of baseline changes. The most common progressive findings were disc signal loss (10%), progressive facet arthrosis (10%), or increased end plate changes (4%). Only two subjects, both with primary radicular complaints, had new findings of probable clinical significance (4%). Subjects having another MR were more likely to have had chronic pain at baseline (odds ratio [OR]=3.19; 95% confidence interval [CI] 1.61-6.32), to smoke (OR=5.81; 95% CI 1.99-16.45), have baseline psychological distress (OR 2.27; 95% CI 1.15-4.49), and have previous disputed compensation claims (OR=2.35; 95% CI 0.97-5.69). Subjects involved in current compensation claims were also more likely to have an MR scan to evaluate the LBP episode (risk ratio=4.75, p<.001), but were unlikely to have significant new findings. New findings were not more frequent in subjects with LBP episodes developing after minor trauma than when LBP developed spontaneously.Findings on MR imaging within 12 weeks of serious LBP inception are highly unlikely to represent any new structural change. Most new changes (loss of disc signal, facet arthrosis, and end plate signal changes) represent progressive age changes not associated with acute events. Primary radicular syndromes may have new root compression findings associated with root irritation.

    View details for PubMedID 17088193

  • Surgical treatment for unstable low-grade isthmic spondylolisthesis in adults: a prospective controlled study of posterior instrumented fusion compared with combined anterior-posterior fusion. spine journal Swan, J., Hurwitz, E., Malek, F., van den Haak, E., Cheng, I., Alamin, T., Carragee, E. 2006; 6 (6): 606-614

    Abstract

    The surgical treatment for low-grade isthmic spondylolisthesis in adults with intractable lumbar pain is usually spinal fusion. It has been postulated that anterior column reconstruction may be relatively advantageous in those patients with unstable slips.To compare the early and medium term treatment efficacy of two common fusion techniques in isthmic spondylolisthesis.Prospective controlled trial comparing single-level posterior-lateral instrumented fusion with combined anterior and posterior-lateral instrumented fusion in sequential matched cohorts of patients with radiographically unstable isthmic spondylolisthesis.Primary outcome measure of success was an Oswestry Disability Index (ODI)

    View details for PubMedID 17088191

  • Prospective radiographic and clinical outcomes of dual-rod instrumented anterior spinal fusion in adolescent idiopathic scoliosis: Comparison with single-rod constructs SPINE Hurford, R. K., Lenke, L. G., Lee, S. S., Cheng, I., Sides, B., Bridwell, K. H. 2006; 31 (20): 2322-2328

    Abstract

    Anterior single or dual-rod instrumentation may be performed for the treatment of main thoracic, thoracolumbar, or lumbar adolescent idiopathic scoliosis (AIS) curves.To compare the results of anterior dual-rod instrumentation in single-major AIS curves with our previous experience using single-rod constructs.Several reports have described the use of anterior single-rod instrumentation for the treatment of AIS curves with acceptable correction rates but with pseudarthroses/implant failures of up to 31%.A total of 60 consecutive patients with AIS (12 males and 48 females; average age 15.3 years) with major thoracic (n = 18) or thoracolumbar/lumbar (n = 42) curves were treated with dual-rod instrumented anterior spinal fusion. Follow-up was 2-5 years. Patients were evaluated prospectively with Scoliosis Research Society (SRS) questionnaires.Major thoracic curves were corrected from a mean of 55 degrees to 27 degrees (51% correction), while major thoracolumbar/lumbar curves were corrected from an average of 51 degrees to 17 degrees at latest follow-up (67% correction). No pseudarthroses were identified. With the use of single-rod constructs, a similar amount of coronal correction was obtained for both thoracic (47%) and thoracolumbar/lumbar curves (70%). However, the pseudarthrosis rate for single-rod constructs was 5.5%. The obvious trend toward a lower pseudarthrosis rate in dual-rod (0/60) versus single-rod (5/90) constructs was not statistically significant (P = 0.07). Follow-up SRS questionnaire data for patients with dual-rod instrumentation showed 95% satisfaction, and 93% would choose the same treatment with similar results in the single-rod instrumentation study, 88% patient satisfaction, and 89% choosing the same treatment. Overall SRS scores improved after treatment (P < 0.01). SRS domain scores improved at a significant level for pain (P = 0.05), self-image (P < 0.01), and function (P = 0.01).In this largest, to our knowledge, single-center report of dual-rod constructs for patients with AIS, a similar amount of radiographic deformity correction was obtained when compared to single-rod implants. However, the absence of any pseudarthroses in the 60 patients with dual-rod is a distinct advantage.

    View details for Web of Science ID 000240696400011

    View details for PubMedID 16985460

  • Apical sublaminar wires versus pedicle screws - Which provides better results for surgical correction of adolescent idiopathic scoliosis? SPINE Cheng, I., Kim, Y., Gupta, M. C., Bridwell, K. H., Hurford, R. K., Lee, S. S., Theerajunyaporn, T., Lenke, L. G. 2005; 30 (18): 2104-2112

    Abstract

    The results of correction for adolescent idiopathic scoliosis (AIS) were compared using apical sublaminar wires versus pedicle screws.To compare comprehensively the 2-year minimum postoperative results of posterior correction and spinal fusion using translational correction through either hybrid hook/sublaminar wire/pedicle screw constructs versus in situ rod-contouring correction with pedicle screw constructs in the treatment of AIS at 2 institutions.Despite the reports of satisfactory correction of scoliotic curves by both apical (sublaminar wire) instrumentation and apical pedicle screw instrumentation, to our knowledge, no reports on the comprehensive comparison of hybrid (hook/sublaminar wire/pedicle screw) instrumentation versus segmental pedicle screw instrumentation exist.A total of 50 patients with AIS at 2 institutions who underwent posterior spinal fusion with sublaminar wire (25 patients) or pedicle screw (25) constructs were sorted and matched according to 4 criteria: (1) similar age at surgery (14.2 years in the sublaminar wire and 14.4 in the pedicle screw group, P = 0.72); (2) similar number of fused vertebrae (11.4 in the sublaminar wire and 11.8 in the pedicle screw group, P = 0.36); (3) similar operative methods; and (4) identical Lenke curve types and similar preoperative major curve measurements (63.5 degrees in the sublaminar wire and 59.5 degrees in the pedicle screw group, P = 0.42). Patients were evaluated preoperatively, immediately postoperatively, and at 2-year follow-up according to radiographic changes in curve correction, operating time, intraoperative blood loss, implant costs, and the Scoliosis Research Society patient questionnaire (SRS-24) scores.After surgery, average major curve correction was 67.4% in the sublaminar wire and 68.1% in the pedicle screw group (P = 0.56). At 2-year follow-up, loss of the major curve correction was 4.6% in the sublaminar wire compared to 5.1% in the pedicle screw group (P = 0.79). Postoperative global coronal and sagittal balance were similar in both groups. No significant difference was found in the average number of levels fused from the distal end vertebra (1.48 in the sublaminar wire and 0.64 in the pedicle screw group, P = 0.21). Operating time averaged 350 minutes in the sublaminar wire and 357 in the pedicle screw group (P = 0.86). Intraoperative blood loss was significantly different in both groups (1791 +/- 816 mL in the sublaminar wire and 824 +/- 440 mL in the pedicle screw group) (P = 0.0003). Average implant cost in the sublaminar wire group (16.0 fixation points; 8,341 US dollars) was significantly lower than that of the pedicle screw group (17.1 fixation points; 13,462 US dollars) (P < 0.0001). Postoperative 2-year SRS-24 scores were similar in both groups (sublaminar wire = 107.3, pedicle screw = 103.5, P = 0.19). There were no neurologic or visceral complications related to sublaminar wire or pedicle screw instrumentation and no reoperations at a minimum 2-year follow-up.Apical sublaminar wire and pedicle screw instrumentation both offer similar major curve correction with similar fusion lengths without neurologic problems in the operative treatment of AIS. Although more expensive, pedicle screw constructs had significantly less blood loss and slightly shorter fusion lengths than the sublaminar wire constructs.

    View details for Web of Science ID 000231885900018

    View details for PubMedID 16166903

  • Use of bone morphogenetic protein-2 for adult spinal deformity SPINE Luhmann, S. J., Bridwell, K. H., Cheng, I., Imamura, T., Lenke, L. G., Schootman, M. 2005; 30 (17): S110-S117

    Abstract

    Prospective, single-center, nonblinded clinical and radiographic analysis of consecutive adult deformity patients treated with recombinant human bone morphogenetic protein-2 (rhBMP-2) without iliac or rib bone graft supplementation.To determine the ability of rhBMP-2 to achieve both anterior and posterior spinal fusion in patients undergoing multilevel fusions for adult spinal deformity.The literature concerning one-level anterior fusions, and potentially one-level posterior fusions, using rhBMP-2 has demonstrated clinical efficacy. No published data exist on the use of rhBMP-2 in multilevel spine fusions.Prospective analysis of patients treated with rhBMP-2 in multilevel anterior and posterior fusions with a minimum 1-year follow-up. There were a total of 95 patient samples (70 total patients; 25 patients had rhBMP-2 used circumferentially): 46 anterior fusions (Group 1), 41 posterior fusions (Group 2), and 8 patients were "compassionate use" fusions (Group 3). In the anterior fusion group (n = 46), mean rhBMP-2/level was 10.8 mg in titanium mesh cages without any bone graft or other substance. The posterior fusion group had only local bone graft, no harvested rib or iliac bone graft (n = 41). The mean rhBMP-2/level was 13.7 mg. The "compassionate use" group (n = 8 patients) consisted of patients who had prior surgeries, prior iliac harvesting, and substantial comorbidities and therefore a higher concentration and different carrier was used. No local bone graft, no harvested bone was used. The mean rhBMP-2/level was 28.6 mg. The median dose was 40 mg for Group 3.For the anterior fusion group (n = 46), operative levels were deemed fused in 89 of the 93 (96%) levels. For the posterior fusion group (n = 41), a solid fusion was assessed in 110 of the 118 (93%) operative levels. For the "compassionate-use" patients, the overall fusion rate was 100% (52 of 52 operative levels).With the use of rhBMP-2, a high rate of apparent fusion was observed for anterior (96%) and posterior (93%) fusions in adult spinal deformity patients. Use of rhBMP-2 results in a promising early fusion rate without the graft harvest site morbidity.

    View details for Web of Science ID 000231770500018

    View details for PubMedID 16138058

  • Use of Bone Morphogenetic Protein-2 for Adult Spinal Deformity Spine Luhmann SJ, Bridwell KH, Cheng I, Imamura T, Lenke LG, Schootman M. 2005; accepted
  • Expression of an extracellular calcium-sensing receptor in rat stomach GASTROENTEROLOGY Cheng, I., Qureshi, I., Chattopadhyay, N., Qureshi, A., Butters, R. R., Hall, A. E., Cima, R. R., Rogers, K. V., Hebert, S. C., Geibel, J. P., Brown, E. M., Soybel, D. I. 1999; 116 (1): 118-126

    Abstract

    Circulating levels of Ca2+ can influence secretory functions and myoelectrical properties of the stomach. A Ca2+-sensing receptor (CaR) has recently been identified in tissues that regulate systemic Ca2+ homeostasis. The aim of this study was to evaluate expression of CaR in the stomach of the rat.In forestomach and glandular stomach, reverse-transcription polymerase chain reaction was used to amplify a 380-base pair product, which is 99% homologous with transcripts obtained in parathyroid and kidney.Northern analysis of gastric mucosal polyA+ RNA revealed 7. 5- and 4.1-kilobase transcripts, similar to those obtained in rat parathyroid and kidney. Immunohistochemistry revealed CaR expression in regions of the submucosal plexus and myenteric neurons. In sections of intact tissue, preparations of primary culture surface cells and surgically dissected gastric glands, staining was observed consistently in epithelial cells of the gastric glands and in gastric surface cells. In parietal cells in isolated gastric glands, intracellular levels of Ca2+ responded to conditions that are known to activate CaR.These are the first reported observations that CaR is expressed in different epithelial cells of mammalian gastric mucosa and its enteric nerve regions. The effects of extracellular Ca2+ on gastric function may be attributable to activation of CaR.

    View details for Web of Science ID 000077785500022

    View details for PubMedID 9869609

  • Identification and localization of the extracellular calcium-sensing receptor in human breast JOURNAL OF CLINICAL ENDOCRINOLOGY & METABOLISM Cheng, I., Klingensmith, M. E., Chattopadhyay, N., Kifor, O., Butters, R. R., Soybel, D. I., Brown, E. M. 1998; 83 (2): 703-707

    Abstract

    The extracellular calcium (Ca2+o)-sensing receptor (CaR) plays a critical role in maintaining Ca2+o homeostasis in mammals by virtue of its presence in parathyroid gland and kidney. The breast is well recognized as a Ca(2+)-handling organ, and the effects of altering Ca2+o on the proliferation of breast epithelial cells are well documented. To date there are no data regarding the expression and localization of CaR in breast tissue. In the present study, we assessed the distribution of CaR messenger ribonucleic acid (mRNA) and protein in normal and fibrocystic human breast tissue as well as in ductal carcinoma of the breast using RT-PCR, Northern analysis, and immunohistochemistry with CaR-specific antisera. In all tissues, RT-PCR performed using sense and antisense primers based on the sequence of the human parathyroid CaR complementary DNA amplified a product of the size expected (425 bp) for genuine CaR transcripts. Nucleotide sequencing of RT-PCR products confirmed more than 99% homology with human parathyroid CaR complementary DNA. Although insufficient quantities of mRNA were isolated from normal and fibrocystic tissue for Northern analysis, a single 5.2-kb CaR transcript was expressed in malignant breast tissue similar to the major CaR transcript in human parathyroid. Localization of CaR protein by immunohistochemistry showed specific CaR staining of the ductal epithelial cells of the breast in all three tissue types. These findings indicate the presence of CaR mRNA and protein in the breast, providing indirect evidence that the CaR may have some role(s) in the control of Ca2+ transport, epithelial cell proliferation, and/or other processes in normal and abnormal breast tissue.

    View details for Web of Science ID 000071823900067

    View details for PubMedID 9467597

  • Identification and localization of extracellular calcium sensing receptor in the rat intesting Am J Phys Chattopadhyay N, Cheng I, Rogers K, Riccardi D, Hall A, Diaz R, Hebert SC, Soybel DI, Brown EM. 1998; 274 (1): G122-30

Conference Proceedings


  • Identification and functional assay of an extracellular calcium-sensing receptor in Necturus gastric mucosa Cima, R. R., Cheng, I., Klingensmith, M. E., Chattopadhyay, N., Kifor, O., Hebert, S. C., Brown, E. M., Soybel, D. I. AMER PHYSIOLOGICAL SOC. 1997: G1051-G1060

    Abstract

    In mammals and amphibians, increases in extracellular Ca2+ can activate bicarbonate secretion and other protective functions of gastric mucosa. We hypothesized that the recently cloned extracellular Ca(2+)-sensing receptor (CaR) is functioning in the gastric mucosa. In Necturus maculosus gastric mucosa, reverse transcription-polymerase chain reaction using primers based on previously cloned CaR sequences amplified a 326-bp DNA fragment that had 84% nucleotide sequence identity with the rat kidney CaR. Immunohistochemical localization of the CaR using specific anti-CaR antiserum revealed its presence on the basal aspect of gastric epithelial cells. In microelectrode studies of Necturus antral mucosa, exposure to elevated Ca2+ (4.8 mM) and the CaR agonists NPS-467 and neomycin sulfate resulted in significant hyperpolarizations of basal membrane electrical potentials and increases in apical-to-basal membrane resistance ratios. Circuit analysis revealed that these changes reflected specific decreases in basolateral membrane resistance. Inhibition of prostaglandin synthesis using indomethacin significantly attenuated these effects. We conclude that the CaR is present and functioning in Necturus gastric antrum.

    View details for Web of Science ID A1997YF88400011

    View details for PubMedID 9374702

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