Clinical Focus

  • Orthopaedic Surgery
  • Osteomyelitis
  • Nonunions and Malunions
  • Limb Lengthening and Reconstruction
  • Limb Salvage
  • Limb Transplantation via Immunotolerance

Academic Appointments

Professional Education

  • Medical Education:UCLA David Geffen School Of Medicine Registrar (1985) CA
  • Residency:University of California at San Francisco School of Medicine (1990) CA
  • Internship:University of California at San Francisco School of Medicine (1986) CA
  • Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (1992)

Research & Scholarship

Current Research and Scholarly Interests

Dr. Lowenberg is a Past President of the Limb Lengthening and Reconstruction Society of North America. His clinical and research interests are in the treatment of nonunions and malunions with or without accompanying osteomyelitis and infection. He is well-published in the field of limb salvage and treatment of devastating limb injuries. He has ongoing research in limb transplantation via immunotolerance as well as biomechanics.


2018-19 Courses


All Publications

  • Unstable Proximal Femur Fractures Treated With Proximal Femoral Locking Plates: A Retrospective, Multicenter Study of 111 Cases. Journal of orthopaedic trauma Collinge, C. A., Hymes, R., Archdeacon, M., Streubel, P., Obremskey, W., Weber, T., Watson, J. T., Lowenberg, D. 2016; 30 (9): 489-495


    A few small case series have found that proximal femur fractures treated with a proximal femur locking plate (PFLP) have experienced more failures than expected. The purpose of this study was to review the clinical results of patients with acute, unstable proximal femur fractures treated with proximal femoral locking plates in a large, multicenter patient cohort.This is a retrospective clinical study.The study included patients from 12 regional trauma centers and tertiary referral hospitals.One hundred eleven consecutive patients with unstable proximal femur fractures stabilized with a PFLP and having required clinical and radiographic follow-up at a minimum of 12 months after injury.Surgical repair of an unstable proximal femur fracture with a PFLP.Treatment failures (failure of fixation, nonunion, and malunion) and need for revision surgery.Forty-six patients (41.4%) experienced a major treatment failure, including failed fixation with or without nonunion (39), surgical malalignment or malunion (18), deep infection (8), or a combination of these. Thirty-eight (34%) patients underwent secondary surgeries, including 30 for failed fixation, nonunion, or both. Treatment failure was found to occur at a significantly higher rate in patients with major comorbidities, in femurs repaired in varus malalignment, and using specific plate designs.Proximal femoral locking plates are associated with a high complication rate, frequently requiring revision or secondary surgeries in the treatment of unstable proximal femur fractures. Given the high complication rate with PFLPs, careful attention to reduction, use of a PFLP implant, and consideration should be given to alternative implants or fixation techniques when appropriate.Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

    View details for DOI 10.1097/BOT.0000000000000602

    View details for PubMedID 27144821

  • A Clinical Perspective on Musculoskeletal Infection Treatment Strategies and Challenges JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Shirwaiker, R. A., Springer, B. D., Spangehl, M. J., Garrigues, G. E., Lowenberg, D. W., Garras, D. N., Yoo, J. U., Pottinger, P. S. 2015; 23: S44-S54


    Orthopaedic implants improve the quality of life of patients, but the risk of postoperative surgical site infection poses formidable challenges for clinicians. Future directions need to focus on prevention and treatment of infections associated with common arthroplasty procedures, such as the hip, knee, and shoulder, and nonarthroplasty procedures, including trauma, foot and ankle, and spine. Novel prevention methods, such as nanotechnology and the introduction of antibiotic-coated implants, may aid in the prevention and early treatment of periprosthetic joint infections with goals of improved eradication rates and maintaining patient mobility and satisfaction.

    View details for DOI 10.5435/JAAOS-D-14-00379

    View details for Web of Science ID 000354129700008

    View details for PubMedID 25808969

  • Advances in the understanding and treatment of musculoskeletal infections. Instructional course lectures Lowenberg, D. W., Watson, J. T., Levin, L. S. 2015; 64: 37-49


    Musculoskeletal infections are a challenging treatment problem for orthopaedic surgeons. Despite advances in aseptic techniques and improved chemotherapeutic options, there has not been a substantial decrease in the incidence of musculoskeletal infections for the past quarter century. Understanding how microbes gain a foothold in tissue and bone and establish a chronic infectious state is imperative to the successful treatment of bone and soft-tissue infections. The methodic establishment of microbes in a sessile state in a mature biofilm represents the basis for instituting a chronic microbial defense system and sustainability in a host. To properly eradicate such infections requires a stepwise treatment algorithm of meticulous and thorough débridement, dead-space management, and soft-tissue and bone reconstruction. A comprehensive understanding of the reconstruction ladder combined with a detailed treatment plan from the initial staging of an infection through final reconstruction can cure an infection and achieve good functional results for patients.

    View details for PubMedID 25745893

  • Malignant Transformation in Chronic Osteomyelitis: Recognition and Principles of Management JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Panteli, M., Puttaswamaiah, R., Lowenberg, D. W., Giannoudis, P. V. 2014; 22 (9): 586-594
  • Temporal trends in the incidence, treatment and outcomes of hip fracture after first kidney transplantation in the United States. American journal of transplantation Sukumaran Nair, S., Lenihan, C. R., Montez-Rath, M. E., Lowenberg, D. W., Chertow, G. M., Winkelmayer, W. C. 2014; 14 (4): 943-951


    It is currently unknown whether any secular trends exist in the incidence and outcomes of hip fracture in kidney transplant recipients (KTR). We identified first-time KTR (1997-2010) who had >1 year of Medicare coverage and no recorded history of hip fracture. New hip fractures were identified from corresponding diagnosis and surgical procedure codes. Outcomes studied included time to hip fracture, type of surgery received and 30-day mortality. Of 69 740 KTR transplanted in 1997-2010, 597 experienced a hip fracture event during 155 341 person-years of follow-up for an incidence rate of 3.8 per 1000 person-years. While unadjusted hip fracture incidence did not change, strong confounding by case mix was present. Using year of transplantation as a continuous variable, the hazard ratio (HR) for hip fracture in 2010 compared with 1997, adjusted for demographic, dialysis, comorbid and most transplant-related factors, was 0.56 (95% confidence interval [CI]: 0.41-0.77). Adjusting for baseline immunosuppression modestly attenuated the HR (0.68; 95% CI: 0.47-0.99). The 30-day mortality was 2.2 (95% CI: 1.3-3.7) per 100 events. In summary, hip fractures remain an important complication after kidney transplantation. Since 1997, case-mix adjusted posttransplant hip fracture rates have declined substantially. Changes in immunosuppressive therapy appear to be partly responsible for these favorable findings.

    View details for DOI 10.1111/ajt.12652

    View details for PubMedID 24712332

  • Principles of Tibial Fracture Management with Circular External Fixation ORTHOPEDIC CLINICS OF NORTH AMERICA Lowenberg, D. W., Githens, M., Boone, C. 2014; 45 (2): 191-?


    There is a growing mass of literature to suggest that circular external fixation for high-energy tibial fractures has advantages over traditional internal fixation, with potential improved rates of union, decreased incidence of posttraumatic osteomyelitis, and decreased soft tissue problems. To further advance our understanding of the role of circular external fixation in the management of these tibial fractures, randomized controlled trials should be implemented. In addition to complication rates and radiographic outcomes, validated functional outcome tools and cost analysis of this method should be compared with open reduction with internal fixation.

    View details for DOI 10.1016/j.ocl.2013.11.003

    View details for Web of Science ID 000335122200007

    View details for PubMedID 24684913

  • Long-term results and costs of muscle flap coverage with Ilizarov bone transport in lower limb salvage. Journal of orthopaedic trauma Lowenberg, D. W., Buntic, R. F., Buncke, G. M., Parrett, B. M. 2013; 27 (10): 576-581


    OBJECTIVES:: To determine long-term outcomes and costs of Ilizarov bone transport and flap coverage for lower limb salvage. DESIGN:: Case series with retrospective review of outcomes with at least six year follow-up. SETTING:: Academic, tertiary care medical center. PATIENTS:: Thirty-four consecutive patients with traumatic lower extremity wounds and tibial defects who were recommended amputation but instead underwent complex limb salvage from 1993 to 2005. INTERVENTION:: Flap reconstruction and Ilizarov bone transport. MAIN OUTCOME MEASUREMENTS:: Outcomes assessed were flap complications, infection, union, malunion, need for chronic narcotics, ambulation status, employment status, and need for re-operations. A cost analysis was performed comparing this treatment modality to amputation. RESULTS:: Thirty-four patients (mean age, 40 years) were included with 14 acute Gustilo IIIB/C defects and 20 chronic tibial defects (nonunion with osteomyelitis). Thirty five muscle flaps were performed with one flap loss (2.9%). The mean tibial bone defect was 8.7 cm, mean duration of bone transport was 10.8 months, and mean follow-up was 11 years. Primary nonunion rate at the docking site was 8.8% and malunion rate was 5.9%. All patients achieved final union with no cases of recurrent osteomyelitis. No patients underwent future amputations, 29% required re-operations, 97% were ambulating without assistance, 85% were working full time, and only 5.9% required chronic narcotics. Mean lifetime cost per patient per year after limb salvage was significantly less than the published cost for amputation. CONCLUSIONS:: The long-term results and costs of bone transport and flap coverage strongly support complex limb salvage in this patient population. LEVEL OF EVIDENCE:: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

    View details for DOI 10.1097/BOT.0b013e31828afde4

    View details for PubMedID 23412507

  • Temporal Trends in the Incidence, Treatment, and Outcomes of Hip Fracture in Older Patients Initiating Dialysis in the United States CLINICAL JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY Nair, S. S., Mitani, A. A., Goldstein, B. A., Chertow, G. M., Lowenberg, D. W., Winkelmayer, W. C. 2013; 8 (8): 1336-1342


    BACKGROUND AND OBJECTIVES: Patients with ESRD experience a fivefold higher incidence of hip fracture than the age- and sex-matched general population. Despite multiple changes in the treatment of CKD mineral bone disorder, little is known about long-term trends in hip fracture incidence, treatment patterns, and outcomes in patients on dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Fourteen annual cohorts (1996-2009) of older patients (≥67 years) initiating dialysis in the United States were studied. Eligible patients had Medicare fee-for-service coverage for ≥2 years before dialysis initiation and were followed for ≤3 years for a first hip fracture. Type of treatment (internal fixation or partial or total hip replacement) was ascertained along with 30-day mortality. Cox and modified Poisson regressions were used to describe trends in study outcomes. RESULTS: This study followed 409,040 patients over 607,059 person-years, during which time 17,887 hip fracture events were recorded (29.3 events/1000 person-years). Compared with patients incident for ESRD in 1996, adjusted hip fracture rates increased until the 2004 cohort (+41%) and declined thereafter. Surgical treatment included internal fixation in 56%, partial hip replacement in 29%, and total hip replacement in 2%, which remained essentially unchanged over time; 30-day mortality after hip fracture declined from 20% (1996) to 16% (2009). CONCLUSIONS: Hip fracture incidence rates remain higher today than in patients reaching ESRD in 1996, despite multiple purported improvements in the management of CKD mineral bone disorder. Although recent declines in incidence and steady declines in associated short-term mortality are encouraging, hip fractures remain among the most common and consequential noncardiovascular complications of ESRD.

    View details for DOI 10.2215/CJN.10901012

    View details for Web of Science ID 000323122500011

    View details for PubMedID 23660182

  • Assessment of Compromised Fracture Healing JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Bishop, J. A., Palanca, A. A., Bellino, M. J., Lowenberg, D. W. 2012; 20 (5): 273-282


    No standard criteria exist for diagnosing fracture nonunion, and studies suggest that assessment of fracture healing varies among orthopaedic surgeons. This variability can be problematic in both clinical and orthopaedic trauma research settings. An understanding of risk factors for nonunion and of diagnostic tests used to assess fracture healing can facilitate a systematic approach to evaluation and management. Risk factors for nonunion include medical comorbidities, age, and the characteristics of the injury. The method of fracture management also influences healing. Comprehensive evaluation includes an assessment of the patient's symptoms, signs, and immune and endocrine status as well as the biologic capacity of the fracture, presence of infection, and quality of reduction and fixation. Diagnostic tests include plain radiography, CT, ultrasonography, fluoroscopy, bone scan, MRI, and several laboratory tests, including assays for bone turnover markers in the peripheral circulation. A systematic approach to evaluating fracture union can help surgeons determine the timing and nature of interventions.

    View details for DOI 10.5435/JAAOS-20-05-273

    View details for Web of Science ID 000303366800003

    View details for PubMedID 22553099