• reddi lab

    Innovation Through Leading Edge Research

UC Davis Department of Orthopaedic Surgery has a rich and storied history of musculoskeletal investigation. We foster our new growth by intra and extra-departmental collaborations across the medical and main campuses. Academic orthopaedic surgeons, musculoskeletal focused physicians, as well as mechanistic scientists are a driving force in research to ensure that our investigations address patient needs and provide practical solutions for improving their care.

Research Facilities

Oak Park Lawrence J. Ellison Musculoskeletal Research Center 

Oak Park Research Center

The 8,000-square-foot center houses a machine shop, materials testing laboratory, cell, and molecular biology laboratory, histology laboratory, tissue culture facilities, microscopy laboratory, and microsurgery suite. Computing facilities are available for mathematical modeling of mechanical stresses in skeletal structures and implants. In addition, the laboratories use an outstanding animal research facility at the 160-acre Animal Resources Service facility on the Davis campus. The laboratory staff includes basic science faculty, administrative staff, technicians, and typically a dozen postgraduate researchers: fellows, residents, visiting scholars, medical students, and graduate students.

List of research labs: 

Collaborative Research Opportunities

UC Davis provides a rich environment for biomedical research. It is the site of the esteemed University of California, Davis, School of Veterinary Medicine — the largest veterinary school in the nation; the world-renown California National Primate Research Center; and the Department of Biomedical Engineering, recipient of a $12 million Whitaker Foundation Leadership/Development grant that triggers some $35 million in matching funds. The Facility for Advanced Instrumentation provides access to a variety of sophisticated research equipment. Research collaborations have involved the Departments of Veterinary Pathology, Mechanical Engineering, Animal Science, Chemical Engineering and Material Science and Biomedical Engineering.

For new clinical research study protocols, please complete the RC Intake Form before IRB submission. 

Click here to explore the Department of Orthopaedic Surgery Clinical Studies. 

Robert H. Allen, M.D.

Nerve regeneration after trauma.

Thomas H. Ambrosi, Ph.D.

We are associated with the UC Davis Institute for Regenerative Cures as well as with the graduate groups of Molecular, Cellular, and Integrative Physiology (MCIP) and Immunology (GGI). We are committed to fostering a welcoming and inclusive environment for people of all backgrounds, identities, and experiences. We actively recruit and support members from underrepresented groups in science and strive to create a workplace culture that values and promotes diversity and equity. We believe that a diverse and inclusive community allows for a wide range of perspectives, ideas, and approaches, leading to more innovative and impactful research.

Christopher O. Bayne, M.D.

Biomechanics, imaging, and surgical treatment of carpal instability; microvascular skeletal reconstruction for the treatment of traumatic bony defects a nonunion.

Blaine A. Christiansen, Ph.D.

Mechanisms of post-traumatic osteoarthritis, bone adaptation to mechanical stimuli, systemic bone response to bone fracture, effect of age in bone mechano-adaptation, advanced imaging of musculoskeletal structure and metabolism.

Ellen P. Fitzpatrick, M.D.

Functional and clinical outcomes following orthopaedic trauma surgery, lower extremity peri-articular trauma, implant biomechanics.

David P. Fyhrie, Ph.D.

Bone and cartilage mechanical properties and risk of osteoporotic fractures; mechanical failure of collagenous structures and rejection of water: implications for bone fracture.

Eric Giza, M.D.

Clinical application of juvenile articular cartilage allografts for osteochondral defects in the talus; arthroscopic approaches to lateral ligament stabilization; bioscaffold treatments for articular cartilage defects; arthroscopic approaches to syndesmosis stabilization; radiographic changes in foot x-rays with progressive weight-bearing; biomechanical testing of Lisfranc injury fixation methods.

Mauro M. Giordani, M.D.

Total joint arthroplasty, knee and hip abductor tendinopathy/tears.

Dominik R. Haudenschild, Ph.D.

We study early responses to joint injury to learn about the pathogenesis of osteoarthritis and to identify intervention strategies.  We study chondrocyte mechanobiology to understand how mechanical forces are translated into biochemical responses.  We study cartilage matricellular proteins to gain insight into how cells interact with growth factors and the extracellular matrix.
We use animal models of joint injury and bone formation, explant models of osteochondral injuries, stem-cell based tissue engineering, and 3-axis bioreactors to mechanically stimulate hydrogel-embedded chondrocytes and stem cells.
We apply the knowledge to translational studies. Example: Intervene with inflammatory gene expression upon joint injury to prevent or delay OA. Example: Enhance BMP-mediated bone regeneration by presenting the growth factor in a biologically relevant context on matricellular proteins.

Brian M. Haus, M.D. 

Non-surgical and surgical outcomes of pediatric sports injuries.

Eric O. Klineberg, M.D.

Focused on the clinical consequences of spinal disorders.  I am invested in clinical outcomes research, particularly in the setting of adult spinal deformity.  Most of this work is focused on the influence of deformity correction on patient outcomes, spinopelvic parameters, sagittal balance, and complications following spinal deformity surgery.  My goals for this research are to be able to provide safe and predictable surgical correction for our most complex patients.  I am proud to be part of our research team here at UC Davis, as well as on the Executive Committee of the International Spine Study Group (ISSG).  Using this information, we can leverage the most current concepts and analytics on spinal surgical correction to provide leading-edge care here locally.

Christopher D. Kreulen, M.D., M.S.

Surgical treatment of osteochondral defects of the talus; use of bone marrow aspirate in orthopaedic surgery; advancing the techniques in Achilles surgery and rehabilitation.

Kent Leach, Ph.D.

The Leach lab uses tissue engineering approaches to generate functional repair tissues to treat deficits in musculoskeletal tissues. Our goal is to provide alternatives to current clinical approaches that are insufficient or ineffective.  We engineer or modify biomaterials for injection or implantation and test the therapeutic potential of these materials using cells from numerous species. We monitor the capacity of these systems to form bone or cartilage under long-term culture and in various preclinical models. We use multiple biomedical imaging modalities to monitor these approaches and work closely with clinicians to ensure a trajectory toward benefiting patients in need.

In addition to engineering replacement musculoskeletal tissues, our lab uses engineering approaches to mimic the microenvironment in cancers of the musculoskeletal system. We aim to use these systems to study the behavior of various cancer cells and identify targetable pathways that may reveal new therapeutic strategies.

Cassandra A. Lee, M.D.

Tissue engineering for articular cartilage defects; integration of self-assembled cartilage constructs for trochlear defects in rabbits.

Mark A. Lee, M.D.

Dr. Lee has experience in using small animal models of bone defects to study multiple strategies at bone repair including a special focus on autologous mesenchymal stem cells on unique scaffolds.  He has extensive collaborations for in vitro and in vivo projects with established scientists in the Department of Biomedical Engineering and at the Institute for Regenerative Cures.  He is also performing clinical studies looking at progenitor cells harvested from patients in the operating room.

He has experience with mechanical testing of clinically used implants in both cadaveric and synthetic bones.  Frequently, there are opportunities for medical student involvement with these areas of study.

Gabriela Loots, Ph.D.

Loots Lab is interested in understanding how functional elements are encoded in the human genome and how proteins and transcriptional regulatory elements orchestrate tissue- and cell-type specific gene regulatory networks in health and disease states. We focus on noncoding regulatory elements that cause congenital skeletal defects and contribute to susceptibility to bone and cartilage degenerative disorders such as osteoporosis and arthritis. We use comparative genomics, genetic engineering, bioinformatics analysis, single-cell RNA-seq, and other high throughput genomic approaches to test our genomic-driven hypotheses. Our studies emphasize on the role of Wnt Signaling in bone, cartilage, and cancer.

Richard A. Marder, M.D.

Prospective, randomized study of rotator cuff syndrome using subacromial bursa; biomechanics of medial patellofemoral ligament repair in reconstruction.

Gavin C. Pereira, M.D., (M.B.B.S.), F.R.C.S. (Eng), F.A.A.O.S.

3D printed bone models for preoperative surgical planning and resident training; computer navigation and knee kinematics; short femoral stems in hip replacements; infections in joint replacements.

Lor Randall, M.D., F.A.C.S., F.A.O.A.

In his third decade of academic orthopaedic surgery, Dr. Randall has a broad portfolio of research interests. Having collaborated with Nobel Laureate Mario Capecchi to create genetically engineered mice using human-derived sarcoma RNA transcripts, Dr. Randall remains interested in pre-clinical modeling of sarcoma genesis and metastasis. Additionally, he is collaborating on tissue bioengineered sarcoma models to better understand the initial and progressive steps of metastasis. Given his experience with population sciences, he is collaborating with others to develop databases to gain an appreciation of the demographic challenges facing adolescence and young adults with cancer. Dr. Randall has a national leadership role in clinical trial development for the Children’s Oncology Group and is a principal investigator for many national sarcoma clinical trials.

Hari Reddi, Ph.D.

Stem cells for chondrogenesis: isolation from bone marrow, muscle and synovium; tissue engineering and regeneration of articular cartilage; engineering lubrication in tissue engineered cartilage.

Rolando F. Roberto, M.D.

Dr. Roberto is interested in the following: 

  • Pediatric spinal disorders,  especially scoliosis, and motion preservation options, including vertebral body tethering.
  • Reduction of wound dehiscence and infection in neuromuscular scoliosis/
  • Promis scores in adult patients undergoing laminoplasty as a motion preserving option for the treatment of cervical myelopathy.
  • Health Care disparities in Pediatric and adult spinal deformity.

Robert M. Szabo, M.D., M.P.H.

Dr. Szabo's research interests are in compressive neuropathies, nerve repair and regeneration biology, wrist biomechanics, tendon healing and adhesion formation, and the epidemiology of injury and injury prevention.

Steven W. Thorpe, M.D., F.A.C.S., F.A.O.A., F.A.A.O.S.

Outcomes and innovations in limb sparing surgery for treatment of bone and soft tissue sarcoma; outcomes and innovations in pelvic resections and reconstruction for sarcoma of the pelvis; determination of the role of cancer stem cells in the propagation and development of metastases and relapse in bone and soft tissue sarcoma.

James Van den Bogaerde, M.D.

Anatomic, biomechanical and clinical outcome studies in knee, shoulder and elbow surgery.

In the future, I would like to do a project on use of regional anesthetic to reduce post-op narcotic use in shoulder surgery. I would also like to look into trends in shoulder arthroplasty using national insurance databases.

Barton L. Wise, M.D., M.Sc., F.A.C.P.

Dr. Wise is a clinician scientist and rheumatologist, and Professor/Professor in Residence. he is also the Interim Vice Chair for Clinical Research for the Department of Orthopaedic Surgery. His research expertise is in chronic diseases of aging, specifically osteoarthritis and risk factors for progression, pain fluctuations and sex differences in the disease, epidemiology and pharmacoepidemiology, and osteoarthritis-related imaging associations. He has directed his research to investigate questions of pain and osteoarthritis, including a focus on mental health and its relation to pain fluctuation. He also has a focus on the use of mindfulness-based stress reduction (MBSR) and mind-body interventions with the goal of reducing pain and improving function in osteoarthritis.  He also continues to engage in imaging-related research, using statistical shape modeling, trajectory analysis, and other approaches to investigate the association of osteoarthritis with sex and other characteristics.  We have ongoing imaging-related studies that could involve students, including ones where students will learn elements of evaluation of radiographs and potentially other imaging of the knee; students will extract data from a large database; students will be part of the discussions of how to understand findings and analysis of the data.