Bio

Bio


Dr. Amanatullah specializes in hip and knee replacements for individuals with osteoarthritis, rheumatoid arthritis, infectious arthritis and avascular necrosis. He also performs revision surgeries of knee and hip implants with problems.

Clinical Focus


  • Orthopaedic Surgery

Academic Appointments


Honors & Awards


  • Magna Cum Laude, University of Southern California (April 1998)
  • Order of the Palm, University of Southern California (April 1998)
  • Medical Scientist Training Program, Albert Einstein College of Medicine (July 1998 – June 2007)
  • Moore Scholarship, Alpha Epsilon Delta (November 1998)
  • Orthopaedic Research Fellowship, Dr. Denny and Jeanene Dickenson (July 2009 – June 2010)
  • Francis W. Noel Award, University of California – Davis (April 2010)
  • Northern California Chapter, Resident Award, Western Orthopaedic Association (April 2010)
  • J. Harold LaBriola Resident Award, California Orthopaedic Association (April 2010)
  • Clinical Scientist Development Program, American Academy of Orthopaedic Surgeons (October 2010)
  • J. Harold LaBriola Resident Award, California Orthopaedic Association (May 2011)
  • Vernon Thompson Award, Western Orthopaedic Association (July 2011)
  • Lloyd W. Taylor Resident Award, California Orthopaedic Association (April 2012)
  • Traveling Clinical Scientist Program, International Cartilage Research Society-Stryker (May 2012)
  • Sanford and Darlene Anzel Award, Western Orthopaedic Association (June 2012)
  • Presentation Award, International Society for Technology in Arthroplasty (October 2013)
  • Foundation Scholarship, Current Concepts in Joint Replacement (December 2013)
  • Young Investigator Research Symposium, Mayo Clinic (March 2014)
  • New Investigator Workshop, Orthopaedic Research Society (May 2014)

Boards, Advisory Committees, Professional Organizations


  • Member, International Cartilage Research Society (2011 - Present)
  • Member, Orthopaedic Research Society (2010 - Present)
  • Candidate Member, American Academy of Hip and Knee Surgeons (2010 - Present)
  • Resident Member, California Orthopaedic Association (2007 - Present)
  • Resident Member, American Academy of Orthopaedic Surgery (2007 - Present)
  • Member, American Medical Association (1998 - Present)
  • Member, University of Southern California, General Alumni Association (1998 - Present)
  • Member, University of Southern California, Skull and Dagger Society (1998 - Present)
  • Lifetime Member, Phi Kappa Phi All-University National Honor Society (1998 - Present)
  • Member, Mortar Board National Honor Society (1997 - Present)
  • Member, Tau Beta Pi Engineering Honor Society (1997 - Present)

Professional Education


  • Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (2016)
  • Fellowship:Mayo Clinic Rochester (2014) MN
  • Residency:University of California Davis Medical Center (2013) CA
  • Internship:University of California Davis Medical Center (2008) CA
  • Medical Education:Albert Einstein College of Medicine (2007) NY
  • Fellowship, Mayo Clinic, Lower Extremity Adult Reconstruction (2014)
  • International Fellowship, University Hospitals Coventry and Warwickshire, Lower Extremity Adult Reconstruction (2013)
  • Traveling Fellowship, International Cartilage Repair Society, Cartilage Regeneration (2012)
  • Residency, University of California – Davis Medical Center, Orthopaedic Surgery (2007)
  • Doctor of Medicine, Albert Einstein College of Medicine of Yeshiva University (2007)
  • Doctor, Albert Einstein College of Medicine of Yeshiva University, Philosophy in Cell Biology (2007)
  • Master of Science, Albert Einstein College of Medicine of Yeshiva University, Developmental and Molecular Biology (2001)
  • Bachelor of Science, University of Southern California, Biomedical Engineering (1998)

Teaching

2016-17 Courses


Graduate and Fellowship Programs


  • Adult Reconstruction (Fellowship Program)

Publications

All Publications


  • Tibiofemoral Dislocation After Total Knee Arthroplasty. journal of arthroplasty Jethanandani, R. G., Maloney, W. J., Huddleston, J. I., Goodman, S. B., Amanatullah, D. F. 2016; 31 (10): 2282-2285

    Abstract

    Tibiofemoral dislocation after total knee arthroplasty (TKA) is a rare complication. Published case reports describe fewer than 6 patients, making conclusions about the etiology, epidemiology, complications, and treatment of tibiofemoral dislocation difficult. This case series highlights common demographic features, potential causes, and difficulties during the management of tibiofemoral dislocations after TKA.Between 2005 and 2014, 14 patients presented to our institution with a tibiofemoral dislocation. Patients were excluded if they had patellofemoral dislocation or subluxation without a tibiofemoral dislocation. We retrospectively reviewed patient demographics, time to first dislocation, number of dislocations, time to surgical intervention, complications, and potential etiologies of tibiofemoral dislocation.Twelve of 14 patients were female. Their mean body mass index was 33 ± 10 kg/m(2). Thirteen of 14 patients had a mean of 2.0 ± 1.4 dislocations. Four patients dislocated due to polyethylene damage and 5 due to ligamentous incompetence. Twelve of 14 patients required open surgical intervention. Complications in this patient population were common with 3 cases of infection, 7 cases of multiple dislocation, 2 cases of popliteal artery laceration, 1 case receiving a fusion, and 1 case receiving an amputation.Patients with tibiofemoral dislocation after TKA are predominantly obese, female, and have a high risk for complications. They dislocate predominantly because of polyethylene damage or ligamentous incompetence. Re-dislocation is common if treated with closed reduction alone.

    View details for DOI 10.1016/j.arth.2016.03.010

    View details for PubMedID 27084503

  • Obesity is Associated With Early Total Hip Revision for Aseptic Loosening. journal of arthroplasty Electricwala, A. J., Narkbunnam, R., Huddleston, J. I., Maloney, W. J., Goodman, S. B., Amanatullah, D. F. 2016; 31 (9): 217-220

    Abstract

    Obesity affects more than half a billion people worldwide, including one-third of men and women in the United States. Obesity is associated with higher postoperative complication rates after total hip arthroplasty (THA). It remains unknown whether obese patients progress to revision THA faster than nonobese patients.A total of 257 consecutive primary THAs referred to an academic tertiary care center for revision THA were retrospectively stratified according to preoperative body mass index (BMI), reason for revision THA, and time from primary to revision THA.When examining primary THAs referred for revision THA, increasing BMI adversely affected the mean time to revision THA. The percentage of primary THAs revised at 5 years was 25% for a BMI of 18-25, 38% for a BMI of 25-30, 56% for a BMI of 30-35, 73% for a BMI of 35-40, and 75% for a BMI of greater than 40 (P < .001). The percentage of primary THAs revised at 15 years was 70%, 82%, 87%, 94%, and 100%, respectively (P < .001). A significant increase in early revision THA for aseptic loosening/osteolysis in obese patients (56%, 23/41) when compared with the nonobese patients (12%, 10/83, P < .001, relative risk ratio = 4.7).Preoperative BMI influences the time of failure of primary THAs referred to an academic tertiary care for revision THA as well as the mechanism of failure. Specifically, obesity increased in the relative risk of early revision THA due to aseptic loosening/osteolysis by 4.7 fold.

    View details for DOI 10.1016/j.arth.2016.02.073

    View details for PubMedID 27108056

  • Obesity is Associated With Early Total Hip Revision for Aseptic Loosening JOURNAL OF ARTHROPLASTY Electricwala, A. J., Narkbunnam, R., Huddleston, J. I., Maloney, W. J., Goodman, S. B., Amanatullah, D. F. 2016; 31 (9): S217-S220
  • Greater inadvertent muscle damage in direct anterior approach when compared with the direct superior approach for total hip arthroplasty. The bone & joint journal Amanatullah, D. F., Masini, M. A., ROGER, D. J., Pagnano, M. W. 2016; 98-B (8): 1036-1042

    Abstract

    We wished to quantify the extent of soft-tissue damage sustained during minimally invasive total hip arthroplasty through the direct anterior (DA) and direct superior (DS) approaches.In eight cadavers, the DA approach was performed on one side, and the DS approach on the other, a single brand of uncemented hip prosthesis was implanted by two surgeons, considered expert in their surgical approaches. Subsequent reflection of the gluteus maximus allowed the extent of muscle and tendon damage to be measured and the percentage damage to each anatomical structure to be calculated.The DA approach caused substantially greater damage to the gluteus minimus muscle and tendon when compared with the DS approach (t-test, p = 0.049 and 0.003, respectively). The tensor fascia lata and rectus femoris muscles were damaged only in the DA approach. There was no difference in the amount of damage to the gluteus medius muscle and tendon, piriformis tendon, obturator internus tendon, obturator externus tendon or quadratus femoris muscle between approaches. The posterior soft-tissue releases of the DA approach damaged the gluteus minimus muscle and tendon, piriformis tendon and obturator internus tendon.The DS approach caused less soft-tissue damage than the DA approach. However the clinical relevance is unknown. Further clinical outcome studies, radiographic evaluation of component position, gait analyses and serum biomarker levels are necessary to evaluate and corroborate the safety and efficacy of the DS approach. Cite this article: Bone Joint J 2016;98-B1036-42.

    View details for DOI 10.1302/0301-620X.98B8.37178

    View details for PubMedID 27482014

  • Biomechanical Consequences of Anterior Femoral Notching in Cruciate-Retaining Versus Posterior-Stabilized Total Knee Arthroplasty. American journal of orthopedics (Belle Mead, N.J.) Jethanandani, R., Patwary, M. B., Shellito, A. D., Meehan, J. P., Amanatullah, D. F. 2016; 45 (5): E268-72

    Abstract

    Anterior femoral notching during total knee arthroplasty is a potential risk factor for periprosthetic supracondylar femur fracture. We conducted a study to determine if the design of the femoral implant changes the risk for periprosthetic supracondylar femur fractures after anterior cortical notching. An anterior cortical defect was created in 12 femoral polyurethane models. Six femora were instrumented with cruciate-retaining implants and 6 with posterior-stabilized implants. Each femur was loaded in external rotation along the anatomical axis. Notch depth and distance from anterior cortical notch to implant were recorded before loading, and fracture pattern was recorded after failure. There were no statistically significant differences in notch depth, distance from notch to implant, torsional stiffness, torque at failure, final torque, or fracture pattern between cruciate-retaining and posterior-stabilized femoral component designs. Periprosthetic fracture after anterior femoral notching is independent of the bone removed from the intercondylar notch. After notching, there likely is no significant difference in femoral strength in torsion between cruciate-retaining and posterior-stabilized designs.

    View details for PubMedID 27552464

  • Antiglide plating of vertical medial malleolus fractures provides stiffer initial fixation than bicortical or unicortical screw fixation CLINICAL BIOMECHANICS Wegner, A. M., Wolinsky, P. R., Robbins, M. A., Garcia, T. C., Maitra, S., Amanatullah, D. F. 2016; 31: 29-32

    Abstract

    Vertical shear fractures of the medial malleolus (44-A2 ankle fractures) occur through a supination-adduction mechanism. There are numerous methods of internal fixation for this fracture pattern.Vertical medial malleolus osteotomies were created in synthetic distal tibiae. The models were divided into four fixation groups: two parallel unicortical cancellous screws, two divergent unicortical cancellous screws, two parallel bicortical cortical screws, or an antiglide plate construct. Specimens were subjected to offset axial loading and tracked using high-resolution video.The antiglide plate construct was stiffer (P<0.05) than each of the other three constructs, and the bicortical screw construct was stiffer (P<0.05) than both unicortical screw constructs. The mean stiffness (standard deviation) was 111 (SD 35) N/mm for the parallel unicortical screw construct, 173 (SD 57) N/mm for the divergent unicortical screw construct, 279 (SD 30) N/mm for the bicortical screw construct, and 463 (SD 91) N/mm for the antiglide plate construct. The antiglide plate construct resisted displacement better (P<0.05) than each of the other three constructs. The mean force for 2mm of articular displacement was 284 (SD 51) N for the parallel unicortical screw construct, 339 (SD 46) N for the divergent unicortical screw construct, 429 (SD 112) N for the bicortical construct, and 922 (SD 297) N for the antiglide plate construct.An antiglide plate construct provides the stiffest initial fixation while withstanding higher load to failure for vertical medial malleolus fractures when compared to unicortical and bicortical screw fixation.

    View details for DOI 10.1016/j.clinbiomech.2015.10.005

    View details for Web of Science ID 000370092900006

    View details for PubMedID 26482240

  • Revision total hip arthroplasty after removal of a fractured well-fixed extensively porous-coated femoral component using a trephine. The bone & joint journal Amanatullah, D. F., Siman, H., Pallante, G. D., Haber, D. B., Sierra, R. J., Trousdale, R. T. 2015; 97-B (9): 1192-1196

    Abstract

    When fracture of an extensively porous-coated femoral component occurs, its removal at revision total hip arthroplasty (THA) may require a femoral osteotomy and the use of a trephine. The remaining cortical bone after using the trephine may develop thermally induced necrosis. A retrospective review identified 11 fractured, well-fixed, uncemented, extensively porous-coated femoral components requiring removal using a trephine with a minimum of two years of follow-up. The mean time to failure was 4.6 years (1.7 to 9.1, standard deviation (sd) 2.3). These were revised using a larger extensively porous coated component, fluted tapered modular component, a proximally coated modular component, or a proximal femoral replacement. The mean clinical follow-up after revision THA was 4.9 years (2 to 22, sd 3.1). The mean diameter of the femoral component increased from 12.7 mm (sd 1.9) to 16.2 mm (sd 3.4; p > 0.001). Two revision components had radiographic evidence of subsidence that remained radiographically stable at final follow-up. The most common post-operative complication was instability affecting six patients (54.5%) on at least one occasion. A total of four patients (36.4%) required further revision: three for instability and one for fracture of the revision component. There was no statistically significant difference in the mean Harris hip score before implant fracture (82.4; sd 18.3) and after trephine removal and revision THA (81.2; sd 14.8, p = 0.918). These findings suggest that removal of a fractured, well-fixed, uncemented, extensively porous-coated femoral component using a trephine does not compromise subsequent fixation at revision THA and the patient's pre-operative level of function can be restored. However, the loss of proximal bone stock before revision may be associated with a high rate of dislocation post-operatively. Cite this article: Bone Joint J 2015;97-B:1192-6.

    View details for DOI 10.1302/0301-620X.97B9.35037

    View details for PubMedID 26330584

  • Acetabular Fractures: What Radiologists Should Know and How 3D CT Can Aid Classification RADIOGRAPHICS Scheinfeld, M. H., Dym, A. A., Spektor, M., Avery, L. L., Dym, R. J., Amanatullah, D. F. 2015; 35 (2): 555-577

    Abstract

    Correct recognition, description, and classification of acetabular fractures is essential for efficient patient triage and treatment. Acetabular fractures may result from high-energy trauma or low-energy trauma in the elderly. The most widely used acetabular fracture classification system among radiologists and orthopedic surgeons is the system of Judet and Letournel, which includes five elementary (or elemental) and five associated fractures. The elementary fractures are anterior wall, posterior wall, anterior column, posterior column, and transverse. The associated fractures are all combinations or partial combinations of the elementary fractures and include transverse with posterior wall, T-shaped, associated both column, anterior column or wall with posterior hemitransverse, and posterior column with posterior wall. The most unique fracture is the associated both column fracture, which completely dissociates the acetabular articular surface from the sciatic buttress. Accurate categorization of acetabular fractures is challenging because of the complex three-dimensional (3D) anatomy of the pelvis, the rarity of certain acetabular fracture variants, and confusing nomenclature. Comparing a 3D image of the fractured acetabulum with a standard diagram containing the 10 Judet and Letournel categories of acetabular fracture and using a flowchart algorithm are effective ways of arriving at the correct fracture classification. Online supplemental material is available for this article.

    View details for DOI 10.1148/rg.352140098

    View details for Web of Science ID 000352561000021

    View details for PubMedID 25763739

  • Revision total hip arthroplasty in patients with extensive proximal femoral bone loss using a fluted tapered modular femoral component. The bone & joint journal Amanatullah, D. F., Howard, J. L., Siman, H., Trousdale, R. T., Mabry, T. M., Berry, D. J. 2015; 97-B (3): 312-317

    Abstract

    Revision total hip arthroplasty (THA) is challenging when there is severe loss of bone in the proximal femur. The purpose of this study was to evaluate the clinical and radiographic outcomes of revision THA in patients with severe proximal femoral bone loss treated with a fluted, tapered, modular femoral component. Between January 1998 and December 2004, 92 revision THAs were performed in 92 patients using a single fluted, tapered, modular femoral stem design. Pre-operative diagnoses included aseptic loosening, infection and peri-prosthetic fracture. Bone loss was categorised pre-operatively as Paprosky types III-IV, or Vancouver B3 in patients with a peri-prosthetic fracture. The mean clinical follow-up was 6.4 years (2 to 12). A total of 47 patients had peri-operative complications, 27 of whom required further surgery. However, most of these further operations involved retention of a well-fixed femoral stem, and 88/92 femoral components (97%) remained in situ. Of the four components requiring revision, three were revised for infection and were well fixed at the time of revision; only one (1%) was revised for aseptic loosening. The most common complications were post-operative instability (17 hips, 19%) and intra-operative femoral fracture during insertion of the stem (11 hips, 12%). Diaphyseal stress shielding was noted in 20 hips (22%). There were no fractures of the femoral component. At the final follow-up 78% of patients had minimal or no pain. Revision THA in patients with extensive proximal femoral bone loss using the Link MP fluted, tapered, modular stem led to a high rate of osseointegration of the stem at mid-term follow-up. Cite this article: Bone Joint J 2015; 97-B:312-17.

    View details for DOI 10.1302/0301-620X.97B3.34684

    View details for PubMedID 25737513

  • Similar Clinical Outcomes for THAs With and Without Prior Periacetabular Osteotomy. Clinical orthopaedics and related research Amanatullah, D. F., Stryker, L., Schoenecker, P., Taunton, M. J., Clohisy, J. C., Trousdale, R. T., Sierra, R. J. 2015; 473 (2): 685-691

    Abstract

    Some patients opt to undergo conversion to a THA for continued pain or progression of hip arthritis after periacetabular osteotomy. Whether patients are at greater risk for postoperative complications, revision THA, poor clinical outcomes, or compromised radiographic results after periacetabular osteotomy is debatable.When compared with a matched cohort of patients who underwent THAs for developmental dysplasia of the hip (DDH) without previous periacetabular osteotomy, we asked whether a THA after a periacetabular osteotomy has (1) a higher complication rate, (2) a higher likelihood of resulting in revision THA, (3) comparable improvements in Harris hip score, and (4) comparable radiographic results.A multicenter retrospective review of 562 patients undergoing 645 periacetabular osteotomies was performed. Twenty-three hips in 22 patients underwent a THA after periacetabular osteotomy. The patients were matched for age, sex, and BMI with 23 hips in 23 patients with DDH undergoing THA without a history of periacetabular osteotomy. Minimum followup for both groups of patients was 2 years (mean, 10 ± 4 years and 6 ± 4 years, respectively). Comparisons were made to answer the study questions based on a retrospective review from prospectively maintained registries of clinical and radiographic information at two participating centers.With the numbers available, there was no difference in complication or revision rates between the two groups (p = 0.489 and 1.000, respectively); however, a post hoc power analysis showed our study was underpowered to detect a difference in the rate of postoperative complications or revision THA. There was marked improvement in Harris hip score with THA after periacetabular osteotomy (p < 0.001) and THA for DDH (p < 0.001), but there was no difference (p = 0.265) in the Harris hip score at final followup between either group. The acetabular component was placed at a mean of 17° more retroversion during THA after periacetabular osteotomy compared with THA for DDH (p = 0.002).This study did not detect any differences in the clinical outcomes in patients undergoing THA after periacetabular osteotomy done with a modern abductor-sparing approach when compared with a matched cohort undergoing THA for DDH. However, even with patients tallied across two high-volume centers during nearly 15 years, our study was underpowered to detect potentially important differences between the THA after periacetabular osteotomy group and the THA for DDH group. The data in this report are suitable as pilot data for future studies and for systematic reviews. Larger multicenter studies are needed to understand how the technical challenges of THA after periacetabular osteotomy affect postoperative complications and revision THA.Level III, therapeutic study.

    View details for DOI 10.1007/s11999-014-4026-7

    View details for PubMedID 25359629

  • Osteonecrosis. Chapman's Comprehensive Orthopaedic Surgery. Arsoy, D., Amanatullah, D. F. 2015
  • Polyethylene Liner Exchange and Pelvic Osteolysis. Master Techniques in Orthpaedic Surgery. Amanatullah, D. F., Maloney, W. J. 2015
  • Total hip replacement in patients with Down syndrome and degenerative osteoarthritis of the hip. The bone & joint journal Amanatullah, D. F., Rachala, S. R., Trousdale, R. T., Sierra, R. J. 2014; 96-B (11): 1455-1458

    Abstract

    Dysplasia of the hip, hypotonia, osteopenia, ligamentous laxity, and mental retardation increase the complexity of performing and managing patients with Down syndrome who require total hip replacement (THR). We identified 14 patients (six males, eight females, 21 hips) with Down syndrome and degenerative disease of the hip who underwent THR, with a minimum follow-up of two years from 1969 to 2009. In seven patients, bilateral THRs were performed while the rest had unilateral THRs. The mean clinical follow-up was 5.8 years (standard deviation (sd) 4.7; 2 to 17). The mean Harris hip score was 37.9 points (sd 7.8) pre-operatively and increased to 89.2 (sd 12.3) at final follow-up (p = 1x10(-9)). No patient suffered a post-operative dislocation. In three patients, four hips had revision THR for aseptic loosening at a mean follow-up of 7.7 years (sd 6.3; 3 to 17). This rate of revision THR was higher than expected. Our patients with Down syndrome benefitted clinically from THR at mid-term follow-up.

    View details for DOI 10.1302/0301-620X.96B11.34089

    View details for PubMedID 25371456

  • Total knee arthroplasty after lower extremity amputation: a review of 13 cases. journal of arthroplasty Amanatullah, D. F., Trousdale, R. T., Sierra, R. J. 2014; 29 (8): 1590-1593

    Abstract

    Below knee amputation protects the ipsilateral knee from osteoarthritis and overloads the contralateral knee predisposing it to symptomatic osteoarthritis. We retrospectively reviewed 13 primary total knee arthroplasty (TKAs) in 12 patients with a prior lower extremity amputation. Twelve TKAs were performed on the contralateral side of the amputated limb while only one TKA was performed on the ipsilateral side. The average clinical follow-up was 6.8 ± 4.8 years. Knee Society Scores improved from 30.4 ± 11.8 to 88.5 ± 4.2 after TKA with a prior contralateral amputation. Three (23.1%) patients with TKA after contralateral amputation had aseptic loosening of the tibial component. Patients experience clinically significant improvement with TKA after lower extremity amputation. Augmentation of tibial fixation with a stem may be advisable during TKA after contralateral amputation.

    View details for DOI 10.1016/j.arth.2014.03.041

    View details for PubMedID 24836176

  • Torsional Properties of Distal Femoral Cortical Defects ORTHOPEDICS Amanatullah, D. F., Williams, J. C., Fyhrie, D. P., Tamurian, R. M. 2014; 37 (3): 158-162

    Abstract

    The optimal management of pathologic long bone lesions remains a challenge in orthopedic surgery. The goal of the current study was to investigate the effect of defect depth on the torsional properties of the distal femur. A laterally placed distal metaphyseal cylindrical defect was milled in the cortex of the distal femur in 20 composite models. The proximal extent of the defects was constant. By decreasing the radius of the cylinder that intersected this predefined cord, 4 different radii defining 4 different depths of resection of the distal femur were created for testing: 17%, 33%, 50%, and 67% cortical defects, when normalized to the width of the femur at the level of resection. Each femur was mounted into a hydraulic axial/torsion materials testing machine and each specimen underwent torsional stiffness testing and torsional failure in external rotation. The specimens with less than a 33% cortical loss consistently demonstrated a superiorly oriented spiral fracture pattern, while the specimens with greater than a 50% cortical loss consistently demonstrated an inferiorly oriented transverse fracture pattern. The cortical defects were all statistically (P<.05) less stiff in torsion as the defect grew larger. There was a strong linear correlation between the mean torsional stiffness and cortical defect size (r(2)=0.977). This observation is supported by finite element analysis. The amount of femur remaining is crucial to stability. This biomechanical analysis predicts a critical loss of torsional integrity when a cortical defect approaches 50% of the width of the femur.

    View details for DOI 10.3928/01477447-20140225-51

    View details for Web of Science ID 000332601700025

    View details for PubMedID 24762144

  • The financial impact of the loss of county indigent patient funding on a single orthopedic trauma surgery service JOURNAL OF TRAUMA AND ACUTE CARE SURGERY Forsh, D. A., Amanantullah, D. F., Coleman, S., Wolinsky, P. R. 2014; 76 (2): 529-533

    Abstract

    We examined the financial ramifications on the orthopedic trauma service after loss of payment to our institution for care of indigent patients. Our institution is the only Level I trauma center located within the county. Before mid-2009, county insurance-eligible patients treated at our institution had their health care paid for by the county. After mid-2009, the county no longer reimbursed our institution for care provided.A retrospective review was performed on 653 county patients treated by the four orthopedic trauma surgeons during a 4-year period including the 2 years before the loss of county payments as well as the 2-year period following the loss of payment. Data collected included demographics, admitting service, injuries treated, length of stay, surgeon billing, and reimbursement. We also classified the urgency of care that was rendered into one of three categories as follows: emergent, urgent, or elective.There was a higher frequency of emergent and urgent procedures and a lower frequency of elective cases performed in the noncontracted period versus the contracted period. During the contracted period, we billed and collected $1,161,036. After the loss of reimbursement from the county, we billed $870,590 and were paid $0. County reimbursements made up 33.5% of the total professional fees billed. There was a 20% net drop in total billing during the noncontracted period, of which the money not reimbursed by the county accounted for 31%.Despite the lack of county payment, our institution continues to provide care to the indigent population. This lack of payment may have significant long-term economic ramifications for the orthopedic trauma surgeons and for our institution. The financial burden preferentially falls on the "safety net" Level I trauma centers and the physicians who take care of patients with urgent and emergent injuries. This burden may be unsustainable in the future.Economic and value-based evaluation, level V.

    View details for DOI 10.1097/TA.0000000000000093

    View details for Web of Science ID 000336386100042

    View details for PubMedID 24458062

  • Giant Cell Tumor of Bone: Current Concepts in Diagnosis and Treatment. Orthopedics Amanatullah, D. F., Clark, T. R., Lopez, M. J., Borys, D., Tamurian, R. M. 2014; 37
  • Total Hip Arthroplasty with and without Prior Periacetabular Osteotomy Clinical Orthopaedics and Related Research Amanatullah, D. F., Stryker, L., Schoenecker, P., Taunton, M. P., Clohish, J. C., Trousdale, R. T., Sierra, R. J. 2014
  • Total Hip Arthroplasty after Lower Extremity Amputation Orthopedics Amanatullah, D. F. 2014
  • Acetabular Fractures: What Radiologists Should Know and How 3D CT Images Can Aid Classification. RadioGraphics, accepted Scheinfeld , M., Amanatullah, D. F. 2014
  • Revision THA with Proximal Bone Deficiency using Fluted Tapered Modular Femoral Components. Bone and Joint Journal Amanatullah, D. F., Howard, J. L., Siman, H., Trousdale, R. T., Mabry, T. M., Berry, D. J. 2014
  • Total Hip Arthroplasty after Lower Extremity Amputation Orthopedics Amanatullah, D. F., Trousdale, R. T., Sierra, R. J. 2014
  • Peri-operative Management of the Total Knee: Patient Selection, Pain Management, Thromoprophylaxis, and Rehabilitation. Clinic Orthopaedic Practice. Amanatullah, D. F., Pallante, G., Paganano, M. W., Sierra, R. J. 2014
  • Removal of Well-fixed Implants. Operative Techniques in Orthopaedic Surgery, 2nd Edition, awaiting publication Amanatullah, D. F., Pagnano, M. W. 2014
  • Effect of Heterotopic Ossification on Hip Range of Motion and Clinical Outcome Journal of Arthroplasty, accepted Vasileiadis, G. I., Amanatullah, D. F., Crenshaw, J., Pudillo, L., Taunton, M. P., Kaufman., K. 2014
  • Distinct Patterns of Gene Expression in the Superficial, Middle and Deep Zones of Bovine Articular Cartilage Journal of Tissue Engineering and Regenerative Medicine Amanatullah, D. F., Yamane, S., Reddi , A. H. 2014; 8 (7)
  • Total Hip Arthroplasty in Down Syndrome Bone and Joint Journal, accepted Amanatullah, D. F., Rachala, R., Sierra, R. J. 2014
  • Minimally Invasive Total Hip Arthroplasty Medscape http://emedicine.medscape.com/article/2000333-overview. Amanatullah, D. F., Di Cesare, P. E. 2014
  • Brachial Artery Avulsion Complicating a Supracondylar Humerus Fracture: A Case Report and Review Current Orthopaedic Practice Sheridan, K., Amanatullah, D. F., Voightlander, J. P., Ertl, J., Moehring, D. 2014; 25
  • Recurrent Carpal Tunnel Syndrome Presenting with the Median Nerve Superficial to the Transverse Carpal Ligament Orthopedics, accepted Amanatullah, D. F., Gaskin, A., Allen, R. H. 2014
  • Similar Clinical Outcomes for Total Hip Arthroplasty with and without Prior Periacetabular Osteotomy Clinical Orthopaedics and Related Research, accpted Amanatullah, D. F., Stryker, L., Schoenecker, P., Taunton, M. P., Clohisy, J. C., Trousdale, R. T., Sierra, R. J. 2014
  • Pre-operative Planning for the Adult Hip The Adult Hip, awaiting publication Pereira, G. C., Amanatullah, D. F., Di Ceasare, P. E. 2014
  • Non-oncologic Total Femoral Replacement: Retrospective Review Journal of Arthroplasty, epub ahead of print Amanatullah, D. F., Trousdale, R. T., Hanssen, A., Lewallen, D. G., Taunton, M. P. 2014
  • Femoroacetabular Impingement: Current Concepts in Diagnosis and Treatment. Orthopedics, accepted, CME Amanatullah, D. F., Antkowiak, T., Pillay, K., Refaat, M., Jamali, A. A. 2014
  • Failure of a constrained acetabular liner without reinforcement ring disruption. American journal of orthopedics (Belle Mead, N.J.) Arthur, J. A., Amanatullah, D. F., Kennedy, G. D., Di Cesare, P. E. 2013; 42 (12): 566-568

    Abstract

    Several risk factors for dislocation after total hip arthroplasty (THA) have been identified including operative-, patient-, and implant-related factors. The following case report describes the dislocation of a revision THA without disruption of the constrained liner or containment ring. The possible mechanisms leading to this type of failure include lever-out impingement and poor abductor function, or tension secondary to prior surgery. Dislocation without disruption of containment ring has not been described for the Pinnacle Acetabular Cup with the Enhanced Stability Constrained Liner (DePuy Orthopaedics, Warsaw, Indiana).

    View details for PubMedID 24471147

  • Identification of the Landmark Registration Safe Zones During Total Knee Arthroplasty Using an Imageless Navigation System JOURNAL OF ARTHROPLASTY Amanatullah, D. F., Di Cesare, P. E., Meere, P. A., Pereira, G. C. 2013; 28 (6): 938-942

    Abstract

    Incorrect registration during computer assisted total knee arthroplasty (CA-TKA) leads to malposition of implants. Our aim was to evaluate the tolerable error in anatomic landmark registration. We incorrectly registered the femoral epicondyles, femoral and tibial centers, as well as the malleoli and documented the change in angulation or rotation. We found that the distal femoral epicondyles were the most difficult anatomic landmarks to register. The other bony landmarks were more forgiving. Identification of the distal femoral epicondyles has a high inter-observer and intra-observer variability. Our observation that there is less than 2mm of safe zone in the anterior or posterior direction during registration of the medial and lateral epicondyles may explain the inability of CA-TKA to improve upon the outcomes of conventional TKA.

    View details for DOI 10.1016/j.arth.2012.12.013

    View details for Web of Science ID 000319846400013

    View details for PubMedID 23566700

  • Free vascularized fibular transfer with langenskiöld procedure for the treatment of congenital pseudarthrosis of the forearm. Techniques in Hand and Upper Extremity Surgery Bauer, A. S., Singh, A. K., Amanatullah, D. F., Lerman, J. A., James, M. A. 2013; 17
  • c-MAF Transcription Factor Regulates ADAMTS-12 Expression in Human Chondrocytes Cartilage Hong, E., Yik, J., Amanatullah, D. F., Di Cesare, P. E., Haudenschild, D. R. 2013; 4
  • Wound Complications Surgery of the Hip Cheung, Y., Amanatullah, D. F., Di Cesare, P. E. 2013
  • Case Report: Artificial Elevation of Prothrombin Time by Telavancin, Clinical Orthopaedics and Related Research Clinical Orthopaedics and Related Research Amanatullah, D. F., Lopez, M., Gosselin, R., Gupta, M. 2013; 471
  • Subtrochanteric Fracture Following Removal of a Porous Tantalum Implant Case Reports in Orthopedics Amanatullah, D. F., Farac, R., McDonald, T. J., Moehring, H. D., Di Cesare, P. E. 2013
  • Minimally Invasive Total Knee Arthroplasty Medscape Amanatullah, D. F. 2013
  • The application of minimally invasive surgical techniques. Part I: total hip arthroplasty. American journal of orthopedics (Belle Mead, N.J.) Amanatullah, D. F., Burrus, M. T., Sathappan, S. S., Levine, B., Di Cesare, P. E. 2012; 41 (10): E134-9

    Abstract

    Traditional surgical approaches often involve making large skin incisions and extensively dissecting healthy tissue to access diseased anatomy. Obviously more desirable is to make smaller incisions and more focused dissections and achieve the same postsurgical outcomes. Minimally invasive surgery (MIS) is gaining popularity in many orthopedic fields, but MIS techniques are not without risk. Continued use of these techniques is a topic of debate. If satisfactory alignment is satisfactory with MIS, and if the complication rates of MIS are similar to those of traditional approaches, it seems sensible to consider the less invasive approaches to enable earlier patient recovery and improve cosmesis. Skeptics claim that there is no advantage in using MIS over time-tested approaches and are concerned that MIS approaches are being implemented before being properly subjected to peer review.

    View details for PubMedID 23376994

  • The application of minimally invasive surgical techniques. Part II: total knee arthroplasty. American journal of orthopedics (Belle Mead, N.J.) Amanatullah, D. F., Burrus, M. T., Sathappan, S. S., Levine, B., Di Cesare, P. E. 2012; 41 (10): E140-4

    Abstract

    Traditional surgical approaches often involve making large skin incisions and extensively dissecting healthy tissue to access diseased anatomy. Obviously more desirable is to make smaller incisions and more focused dissections and achieve the same postsurgical outcomes. Minimally invasive surgery (MIS) is gaining popularity in many orthopedic fields, but MIS techniques are not without risk. Continued use of these techniques is a topic of debate. If alignment is satisfactory with MIS, and if the complication rates of MIS are similar to those of traditional approaches, it seems sensible to consider the less invasive approaches to enable earlier patient recovery and improve cosmesis. Skeptics claim that there is no advantage in using MIS over time-tested approaches and are concerned that MIS approaches are being implemented before being properly subjected to peer review.

    View details for PubMedID 23376995

  • Effect of mini-fragment fixation on the stabilization of medial malleolus fractures JOURNAL OF TRAUMA AND ACUTE CARE SURGERY Amanatullah, D. F., McDonald, E., Shellito, A., Lafazan, S., Cortes, A., Curtiss, S., Wolinsky, P. R. 2012; 72 (4): 948-953

    Abstract

    Oblique fractures of the medial malleolus can arise from the application of axial force at various anatomic positions of the ankle, including supination-external rotation, pronation-external rotation, or pronation abduction. Although a variety of techniques exist to provide fixation of horizontal medial malleolus fractures, the optimal technique and pattern for internal fixation remains unclear. The aim of this study was to evaluate the mechanical properties of four different fixation methods for fractures of the medial malleolus.Identical oblique osteotomies were created in synthetic distal tibiae using a jig. The specimens were divided into four fixation groups: contoured 2.0 mm mini-fragment T-plate, figure-of-eight tension band wire, construct two parallel 4.0 mm cancellous screws, and two divergent 4.0 mm cancellous screws. The specimens were tested using offset axial tension at 10 mm/min until 2 mm of joint line displacement.The average stiffness in tension and force at 2 mm of joint line displacement of the plate construct was significantly greater than any of the other constructs (p < 0.05), whereas the average stiffness in tension of the other three groups were not significantly different from each other (p > 0.05).Using a contoured 2.0 mm mini-fragment T-plate as the method of fixation resulted in an at least 25% stiffer construct during tension and required at least 24% more force for 2 mm of joint line displacement when compared with more traditional methods of fixation in an osteotomy model of an oblique medial malleolus fracture.

    View details for DOI 10.1097/TA.0b013e318249697d

    View details for Web of Science ID 000302784600033

    View details for PubMedID 22491610

  • Effect of divergent screw fixation in vertical medial malleolus fractures JOURNAL OF TRAUMA AND ACUTE CARE SURGERY Amanatullah, D. F., Khan, S. N., Curtiss, S., Wolinsky, P. R. 2012; 72 (3): 751-754

    Abstract

    This study qualified and evaluated the mechanical properties of three different screw orientations used for fixation of vertical shear fractures of the medial malleolus.Identical vertical osteotomies were created in synthetic distal tibiae using a jig. The specimens were assigned to one of the three fixation groups (n = 8 per group): (1) parallel: two 40 mm length, 4.0 mm diameter screws placed parallel to each other in the transverse plane; (2) convergent: two 40 mm length, 4.0 mm diameter screws placed 25 degree convergent to each other in the transverse plane; and (3) divergent: two 40 mm length, 4.0 mm diameter screws placed 15 degree divergent to each other in the transverse plane. The specimens were tested using offset axial loading at 1 mm/s until 2 mm of displacement.The average stiffness was 102 N/mm ± 51 N/mm for the parallel group, 109 N/mm ± 37 N/mm for the convergent group, and 185 N/mm ± 73 N/mm for the divergent group. The average stiffness of the divergent group was significantly greater than either the parallel (p < 0.05) or convergent (p < 0.05) groups. The divergent group was 81.4% more stiff than the parallel group and 69.7% more stiff than the convergent group. The average load at 2 mm of displacement was 324 N ± 87 N for the parallel group, 373 N ± 95 N for the convergent group, and 512 N ± 170 N for the divergent group. The average load at failure of the divergent group was significantly (p < 0.05) greater than the parallel groups. The divergent group was required 58.0% more force at 2 mm of displacement than the parallel group and 37.3% more force at 2 mm of displacement than the convergent group.The use of a divergent screw pattern resulted in a stiffer fixation construct that requires more force for 2 mm of displacement when used to stabilize an osteotomy model of vertical shear medial malleolus fractures.

    View details for DOI 10.1097/TA.0b013e31823b8b9f

    View details for Web of Science ID 000301371100046

    View details for PubMedID 22491565

  • Patellar Polyethylene Spinout After Low-contact Stress, High-congruity, Mobile-bearing Patellofemoral Arthroplasty ORTHOPEDICS Amanatullah, D. F., Jamali, A. A. 2012; 35 (2): E272-E276

    Abstract

    A low-contact stress, high-congruity, mobile-bearing patellofemoral joint arthroplasty decreases the contact force in the patellofemoral joint, theoretically reducing patellar polyethylene wear and increasing implant longevity. This article describes the case of a 47-year-old obese woman who presented with pain and loss of extension after a low-contact stress, high-congruity, mobile-bearing patellofemoral joint arthroplasty. Radiographs revealed dislocation (ie, spinout) of the patellar polyethylene. Patellar polyethylene spinout is a rare complication of metal-backed, mobile-bearing patellar resurfacing. Theoretically, patellar polyethylene spinout in low-contact stress, high-congruity, mobile-bearing patellofemoral arthroplasty is related to implant design and the placement of the metal base plate. Ultimately, the articulation of low-contact stress, high-congruity, mobile-bearing patellofemoral arthroplasty may be too congruent to resist the forces of the patellofemoral joint, particularly in patients who are obese, and the patellar rotation allowed by this articulation may not be sufficient for all patients. Should patellar spinout occur, replacement of the polyethylene is not sufficient to correct the problem; hence, revision of the patellar and trochlear components is required because it remains unclear whether failure is secondary to patellar or trochlear design deficiencies.

    View details for DOI 10.3928/01477447-20120123-27

    View details for Web of Science ID 000300057300025

    View details for PubMedID 22310419

  • Right Elbow Pain in a 21-year-old Pregnant Female Shoulder and Elbow Amanatullah, D. F., Bozzio, A. E., Mallon, Z. O., Mak, W. H., Borys, D., Tamurian, R. M. 2012; 4
  • Surgical Intern Survival Guide Einstein Journal of Biology and Medicine Amanatullah, D. F. 2012; 27
  • Identification of a Mechanoresponsive 3 Kb Promoter Region in the Human Cartilage Oligomeric Matrix Protein Gene. Tissue Engineering Part A Amanatullah, D. F., Lu, J., Hecht, J., Posey, K., Yik, J., Di Cesare, P. E., Haudenschild, D. R. 2012; 18
  • Comparison of Surgical Outcomes and Implant Wear Between Ceramic-Ceramic and Ceramic-Polyethylene Articulations in Total Hip Arthroplasty JOURNAL OF ARTHROPLASTY Amanatullah, D. F., Landa, J., Strauss, E. J., Garino, J. P., Kim, S. H., Di Cesare, P. E. 2011; 26 (6): 72-77

    Abstract

    The results of a prospective multicenter trial comparing 357 hips randomized to total hip arthroplasty with either ceramic-ceramic or ceramic-polyethylene couplings are presented. No statistically significant difference in clinical outcomes scores between the ceramic-ceramic and ceramic-polyethylene groups was observed at any time interval. The mean linear rate was statistically lower (P < .001) in the ceramic-ceramic group (30.5 μm/year) when compared with the ceramic-polyethylene group (218.2 μm/year). The rates of ceramic implant fracture (2.6%) and audible component-related noise (3.1%) were statistically higher in the ceramic-ceramic group when compared with the ceramic-polyethylene group (P < .05). Lastly, there was no statistically significant difference in the dislocation or revision rate between the groups at the time of last clinical follow-up.

    View details for DOI 10.1016/j.arth.2011.04.032

    View details for Web of Science ID 000294393000014

    View details for PubMedID 21680138

  • Pelvic osteoid osteoma in a skeletally mature female. American journal of orthopedics (Belle Mead, N.J.) Amanatullah, D. F., Mallon, Z. O., Mak, W. H., Borys, D., Tamurian, R. M. 2011; 40 (9): 476-478

    Abstract

    Osteoid osteoma is the most common bone-producing tumor that typically presents with "throbbing night pain" and that improves dramatically with use of low-dose salicylates. Few cases of pelvic osteoid osteoma have been reported, and most have involved patients younger than age 30. Surgical excision classically has been the treatment of choice, but, recently, less invasive modalities, including radiofrequency ablation, have begun to supplant surgical management of osteoid osteoma, resulting in a decrease in the need for definitive surgical diagnosis and treatment. We present a rare case of osteoid osteoma in the pelvis of a woman older than age 30.

    View details for PubMedID 22022677

  • Applying computer-assisted navigation techniques to total hip and knee arthroplasty. American journal of orthopedics (Belle Mead, N.J.) Amanatullah, D. F., Burrus, M. T., Sathappan, S. S., Levine, B., Di Cesare, P. E. 2011; 40 (8): 419-426

    Abstract

    Appropriate implant alignment is a major goal of total joint arthroplasty. Obtaining appropriate alignment typically involves making intraoperative decisions in response to visual and tactile feedback. Integrated computer-based systems provide the option of continuous real-time feedback and offer the potential to decrease intraoperative errors while enhancing the surgical learning experience. Computer-assisted orthopedic surgery helps the surgeon perform both intraoperative and postoperative technical audits of implant alignment. Improving implant alignment can be correlated with improved long-term clinical outcomes. However, despite emerging data, many surgeons remain wary of computer-assisted orthopedic surgery.

    View details for PubMedID 22016871

  • Biomechanical properties of volar hybrid and locked plate fixation in distal radius fractures. journal of hand surgery Sokol, S. C., Amanatullah, D. F., Curtiss, S., Szabo, R. M. 2011; 36 (4): 591-597

    Abstract

    We compare the biomechanical properties of a volar hybrid construct to an all-locking construct in an osteoporotic and normal comminuted distal radius fracture model.Groups of 28 normal, 28 osteoporotic, and 28 over-drilled osteoporotic left distal radius synthetic bones were used. The normal group consisted of synthetic bone with a standard foam core. The osteoporotic group consisted of synthetic bone with decreased foam core density. The over-drilled osteoporotic group consisted of synthetic bone with decreased foam core density and holes drilled with a 2.3 mm drill, instead of the standard 2.0 mm drill, to simulate the lack of purchase in osteoporotic bone. Within each group, 14 synthetic bones were plated with a volar locking plate using an all-locking screw construct, and 14 synthetic bones were plated with a volar locking plate using a hybrid screw construct (ie, both locking and nonlocking screws). A 1-cm dorsal wedge osteotomy was created with the apex 2 cm from the volar surface of the lunate facet. Each specimen was mounted to a materials testing machine, using a custom-built, standardized axial compression jig. Axial compression was delivered at 1 N/s over 3 cycles from 20 N to 100 N to establish stiffness. Each sample was stressed to failure at 1 mm/s until 5 mm of permanent deformation occurred.Our results show no difference in construct stiffness and load at failure between the all-locking and hybrid constructs in the normal, osteoporotic, or over-drilled osteoporotic synthetic bone models. All specimens failed by plate bending at the osteotomy site with loss of height.Although volar locking plates are commonly used for the treatment of distal radius fractures, the ideal screw configuration has not been determined. Hybrid fixation has comparable biomechanical properties to all locking constructs in the fixation of metaphyseal fractures about the knee and shoulder and might also have a role in the fixation of distal radius fractures.

    View details for DOI 10.1016/j.jhsa.2010.12.032

    View details for PubMedID 21463723

  • Intermediate-term Radiographic Patient Outcomes in Revision Hip Arthroplasty with a Modular Calcar Design and Plasma Porous Coating Journal of Arthroplasty Amanatullah, D. F., Meehan, J. P., Cullen, A. B., Kim, S. H., Jamali, A. A. 2011; 26
  • Current Treatment Options for Osteonecrosis of the Femoral Head: Part 1, Diagnosis and Nonoperative Management. American Journal of Orthopedics Amanatullah, D. F., Strauss, E. J., Di Cesare, P. E. 2011; 40
  • Current Treatment Options for Osteonecrosis of the Femoral Head: Part II, Operative Management American Journal of Orthopedics Amanatullah, D. F., Strauss, E. J., Di Cesare, P. E. 2011; 40
  • Transverse Deficiency in the Upper Limb Orthopaedic Knowledge Update: Pediatrics James, M. A., Amanatullah, D. F. 2011
  • Hip Resurfacing Arthroplasty: A Review of the Evidence for Surgical Technique, Outcome, and Complications ORTHOPEDIC CLINICS OF NORTH AMERICA Amanatullah, D. F., Cheung, Y., Di Cesare, P. E. 2010; 41 (2): 263-?

    Abstract

    Hip resurfacing arthroplasty has reemerged as a valid reconstruction option for the osteoarthritic hip. Patient selection is critical for excellent surgical outcomes, especially when compared with total hip arthroplasty. However, concerns regarding surgical technique and postsurgical complications persist. The authors review the evidence for surgical technique, outcomes, and complications related to modern metal-on-metal hip resurfacing arthroplasty.

    View details for DOI 10.1016/j.ocl.2010.01.002

    View details for Web of Science ID 000277461800015

    View details for PubMedID 20399365

  • Selection of Aggressive Metastatic Carcinoma after Treatment of Epithelioid Osteosarcoma Orthopedics Amanatullah, D. F., Ngann, K. K., Borys, D., Tamurian, R. M. 2010; 33
  • Alternative Fixation for Small Medial Malleolus Fractures Orthopedics Amanatullah, D. F., Wolinsky, P. R. 2010; 33
  • PU.1 inhibits the erythroid program by binding to GATA-1 on DNA and creating a repressive chromatin structure EMBO JOURNAL Stopka, T., Amanatullah, D. F., Papetti, M., Skoultchi, A. I. 2005; 24 (21): 3712-3723

    Abstract

    Transcriptional repression mechanisms are important during differentiation of multipotential hematopoietic progenitors, where they are thought to regulate lineage commitment and to extinguish alternative differentiation programs. PU.1 and GATA-1 are two critical hematopoietic transcription factors that physically interact and mutually antagonize each other's transcriptional activity and ability to promote myeloid and erythroid differentiation, respectively. We find that PU.1 inhibits the erythroid program by binding to GATA-1 on its target genes and organizing a complex of proteins that creates a repressive chromatin structure containing lysine-9 methylated H3 histones and heterochromatin protein 1. Although these features are thought to be stable aspects of repressed chromatin, we find that silencing of PU.1 expression leads to removal of the repression complex, loss of the repressive chromatin marks and reactivation of the erythroid program. This process involves incorporation of the replacement histone variant H3.3 into nucleosomes. Repression of one transcription factor bound to DNA by another transcription factor not on the DNA represents a new mechanism for downregulating an alternative gene expression program during lineage commitment of multipotential hematopoietic progenitors.

    View details for DOI 10.1038/sj.emboj.7600834

    View details for Web of Science ID 000233118500004

    View details for PubMedID 16222338

  • Eat to Live: The Revolutionary Formula for Fast and Sustained Weight Loss Einstein Journal of Biology and Medicine Amanatullah, D. F. 2004; 21
  • The cell cycle in steroid hormone regulated proliferation and differentiation. Minerva endocrinologica Amanatullah, D. F., Zafonte, B. T., Pestell, R. G. 2002; 27 (1): 7-20

    Abstract

    Steroid hormones mediate pleiotropic cellular processes involved in metabolism, cellular proliferation, and differentiation. The ability of the cell to respond to its hormonal environment is transduced by nuclear receptors (NRs) that bind both hormone and DNA. Hence, NRs represent a link between the external hormonal milieu and the genes that control cell physiology. Therefore, understanding the effects of steroid hormones on proliferation and differentiation requires a knowledge of the cell cycle, the interaction of NRs at the level of transcription, and the potential areas of cross-talk between these two.

    View details for PubMedID 11845110

  • The Importance of a Physician's Wit: A Critical Analysis of Science in Medicine Einstein Quarterly Journal of Biology and Medicine Amanatullah, D. F. 2002; 19
  • Translational Research: From the Bench to the Bedside and Back Einstein Quarterly Journal of Biology and Medicine Amanatullah, D. F. 2001; 18
  • Ras Regulation of Cyclin D1 Promoter. Methods in Enzymology Amanatullah, D. F., Zafonte, B. T., Albanese, C., Fu, M., Messiers, C., Hassell, J., Pestell, R. G. 2001; 333
  • Ras Regulation of Cyclin-dependent Immunoprecipitation Kinase Assays Methods in Enzymology Zafonte, B. T., Amanatullah, D. F., Sage, D., Augenlicht, L. H., Pestell, R. G. 2001; 333
  • Cell-cycle dysregulation in breast cancer: Breast cancer therapies targeting the cell cycle FRONTIERS IN BIOSCIENCE Zafonte, B. T., Hulit, J., Amanatullah, D. F., Albanese, C., Wang, C. G., Rosen, E., Reutens, A., Sparano, J. A., Lisanti, M. P., Pestell, R. G. 2000; 5: D938-D961

    Abstract

    Breast cancer is the most commonly diagnosed cancer in American women. The underlying mechanisms that cause aberrant cell proliferation and tumor growth involve conserved pathways, which include components of the cell cycle machinery. Proto-oncogenes, growth factors, and steroids have been implicated in the pathogenesis of breast cancer. Surgery, local irradiation, and chemotherapy have been the mainstay of treatment for early and advanced stage disease. Potential targets for selective breast cancer therapy are herein reviewed. Improved understanding of the biology of breast cancer has led to more specific "targeted therapies" directed at biological processes that are selectively deregulated in the cancerous cells. Examples include tamoxifen for estrogen receptor positive tumors and imunoneutralizing antibodies such as trastuzumab for Her2/neu overexpressing tumors. Other novel anticancer agents such as paclitaxel, a microtubule binding molecule, and flavopiridol, a cyclin dependent kinase inhibitor, exert their anticancer effects by inhibiting cell cycle progression.

    View details for Web of Science ID 000166736900004

    View details for PubMedID 11102317

  • The Integrin-linked Kinase Regulates the Cyclin D1 Gene through Glycogen Synthase Kinase 3 and cAMP-responsive Element-binding Protein-dependent Pathways Journal of Biological Chemistry D'Amico, M. J., Hulit, J., Amanatullah, D. F., Zafonte, B. T., Albanese, C., Bouzahzah, B., Fu, M., Augenlicht, L. H., Donehower, L. A., Takemaru, K. I., Moon, R. T., Davis, R., Lisanti, M., Shtutman, M., Zhurinsky, J., Ben-Ze'ev,, A., Troussard, A. A., Dedhar, S., Pestell, R. G. 2000; 275
  • Cell-cycle Dysregulation and Molecular Mechanisms of Prostate Cancer Frontiers in Bioscience Amanatullah, D. F. 2000
  • Adenosine receptor mediates motility in human melanoma cells BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS Woodhouse, E. C., Amanatullah, D. F., SCHETZ, J. A., Liotta, L. A., Stracke, M. L., Clair, T. 1998; 246 (3): 888-894

    Abstract

    Cell motility is an essential component of tumor progression and metastasis. A number of factors, both autocrine and paracrine, have been found to influence cell motility. In the present study, adenosine and adenine nucleotides directly stimulated chemotaxis of A2058 melanoma cells in the absence of exogenous factors. Three adenosine receptor agonists stimulated motility in the melanoma cells and two adenosine receptor antagonists strongly inhibited the chemotactic response to both adenosine and AMP. The chemotactic stimulation by adenosine and AMP was pertussis toxin sensitive. Otherwise unresponsive Chinese hamster ovary cells which were transfected with the adenosine A1 receptor cDNA acquired the direct, pertussis toxin sensitive, chemotactic response to adenosine, and this response was inhibited by adenosine receptor antagonists. These findings demonstrate that adenosine and adenine nucleotides are capable of stimulating chemotaxis of tumor cells mediated through an adenosine receptor, probably of the A1 subtype. The possibility of antimetastatic therapies based on inhibition of adenosine receptor activity is raised.

    View details for Web of Science ID 000074061900057

    View details for PubMedID 9618307

  • Development of Metastases Cutaneous Oncology Woodhouse, E., Amanatullah, D. F., Duray, P., Liotta, L. 1998