Orthopaedic Research Summaries
A. Bobby Chhabra, MD Lillian T. Pratt Distinguished
Professor; Chair, Department of Orthopaedic Surgery; Division
Head, Hand Surgery . Area of expertise: hand, wrist, elbow, and
peripheral nerve surgery.
Mark Abel, MD Charles J. Frankel Professor of Orthopaedic Surgery; Vice Chair, Department of Orthopaedic Surgery; Associate Chief Medical Officer for Surgical Services, University of Virginia Medical Center; Medical Director, University of Virginia Motion Analysis and Motor Performance Laboratory; Division Head, Division of Pediatric Orthopaedics.
Current research activities include outcome assessments from treatment of childhood onset spinal deformity including scoliosis. He is also involved in clinical research on cerebral palsy; including the management of their walking impairments as well as disorders of the hip and spine.
Gary Balian, PhD Professor of
Orthopaedics and Professor of Biochemistry and Molecular Genetics,
Director of Orthopaedic Research Laboratories, and Director of T32
Musculoskeletal Research Training Program. Dr. Balian is an
internationally recognized cell biologist. He is responsible for
coordinating the overall schedule for the basic science lecture series
and oversees the residents involved in laboratory research. He is also
responsible for instruction in biochemical aspects of orthopaedics. His
research interests involve prostate cancer cell-bone marrow adhesion
mediators. The contribution of this research to our understanding of
cancer cell homing to bone may be forthcoming from the identification
of molecular targets in bone. Bone repair is clearly a very important
area of consideration in the field of musculoskeletal tissue
regeneration. Inclusion of bone targeting factors in synthetic or
natural polymers potentiate repair through mechanisms that are well
characterized biologically at the cellular and molecular levels. Two
unique bone targeting peptides potentiate the differentiation of
mesenchymal cells in vitro, moreover, the peptides promote bone repair
in critical sized unicortical defects. The potential anabolic effects
of these novel peptides on bone density and gene expression is under
Thomas E. Brown, MD Associate Professor of Orthopaedic Surgery. Involved in clinical research concerning primary and revision hip and knee arthroplasty.
James A. Browne, MD Assistant Professor of Orthopaedic Surgery. His research interests include clinical outcomes following hip and knee replacement. Ongoing projects include investigating failed metal-on-metal hip implants and the impact of obesity on postoperative complications. He has been involved in clinical trials of implants and the investigation of novel surgical techniques in joint replacement.
Eric W. Carson, MD
Associate Professor, University of Virginia; Medical Clinical Director,
McCue Sports Medicine Center. Osteochondral injuries, ligament grafts,
shoulder instability (articular cartilage matrix degradation,
biomechanics, anatomy, physiology and cartilage research).
Nerve injuries caused by direct trauma include transection, crush injury or avulsion of the nerve from the muscle. When an injury (avulsion injury) occurs at the neuromuscular junction (NMJ) the motor endplates undergo fibrotic degeneration1 which can result in loss of limb function. Current therapeutic intervention for avulsion injuries is the neurotization procedure which historically has yielded poor outcomes. Therefore alternative therapeutic approaches are urgently required for nerve avulsion repair. Although stem cell based therapy has shown promising results for enhancement of nerve repair in animal models none of these studies have been conducted using a model that depicts nerve avulsion injury at the NMJ. A variety of stem cells including embryonic stem cells (ESCs), induced pleuripotent stem cells (iPSCs) and adult stem cells isolated from various tissues have been used to enhance nerve repair in these animal models2-8. However, a recent report demonstrated that iPSCs can induce immune response in the host9 and there are severe ethical issues concerned with use of ESCs. It is widely accepted that adult stem cells adipose derived stem cells (ADSCs) offer promising alternative since ADSCs can be isolated repeatedly using a simple procedure10, possess significant differentiation potential and proliferative capacity11, resistance to senescence11-13, and high frequency of occurrence14,15 It is well known that the efficacy of adult stem cells in augmenting axonal regeneration can be significantly enhanced by expressing nerve growth factor (NGF)16-18. However, such genetic modification involves use of viral vectors which is not approved by the FDA in the USA. Another approach is to activate the stem cells before delivery to the injured site using nerve (glial cell or schwann cell) induction medium (NIM) 4,6,7,19-21 motor neuron induction medium (MNIM)22 or NGF. Use of these media is exceedingly expensive making this strategy impractical. Therefore alternative approaches to activating the stem cells are needed. It was reported in 2008 that inhibition of TGF-β and BMP signaling pathways in ESCs and iPSCs can induce neuronal differentiation. Based on these observations and using a rat model depicting avulsion injury at the NMJ our lab is developing a practical therapeutic approach with a potential high success rate in nerve regeneration and muscular re-innervation by employing ADSCs and inexpensive inhibitors of TGF-β as well as BMP pathways.
Areas of interest include
1. articular cartilage repair for damaged knee cartilage
2. osteochondral plug transfers for bone and cartilage defects in the knee in high level athletes
3. hyaluronic acid (HA) injections for knee pain involving the kneecap, also called patellofemoral pain
4. a novel implantable spring device for the knee to unload arthritic joints
5. development and studying new devices and methods to fix or tenodese the biceps tendon in the shoulder for SLAP tears and biceps tendon problems
6. improved techniques in ACL reconstruction, meniscal repair, and rotator cuff repair
7. emerging understanding of how to evaluate and treat a sports hernia
Joseph Hart, PhD Assistant Professor, Department of Orthopaedic Surgery. Patients who opt for reconstruction after anterior cruciate ligament injury often want to remain active. Unfortunately, these patients often experience early-onset osteoarthritis. My research focus, which builds from my student experience and my research in patient-oriented outcomes, aims to help patients with major knee injuries or surgery achieve their goals and lead a healthy lifestyle. Central to this research is identification modifiable neuromuscular factors that may expose patients to risk during activity and exercise, the development of translational therapies and rehabilitation strategies, and intervening in these patients early and often after major knee joint injuries.
Xudong (Joshua) Li, MD, PhD Assistant Professor,
Department of Orthopaedic Surgery. His