Following his fellowship, Kang joined the faculty of the Department of Orthopaedic Surgery at the University of Pittsburgh School of Medicine, where he was later promoted to full professor and appointed the UPMC Endowed Chair in Orthopaedic Surgery in 2007. He also served as the executive vice chairman for clinical services and director of the Ferguson Laboratory Musculoskeletal Research Center for Spine Research at the University of Pittsburgh Medical Center (UPMC).
In 2015, Kang was appointed chair of the Department of Orthopaedic Surgery at BWH, succeeding Thomas S. Thornhill. In 2016, he received the Thomas and Karen Thornhill Professorship at Harvard Medical School. After a ten-year tenure as chair, he transitioned to chair emeritus and distinguished professor at Harvard Medical School in 2025.
Kang served as President of the American Board of Orthopaedic Surgery for the 2023–2024 term, a role that kept him centrally engaged with issues of board certification, maintenance of certification, and professional standards for orthopaedic surgeons nationwide. As ABOS president he publicly addressed evolving issues such as the responsible use of artificial intelligence in assessment and exam workflows
In 2016, he was also president of the International Society for the Study of the Lumbar Spine.
Kang also investigated molecular therapies for disc degeneration, including gene therapy. His studies demonstrated the feasibility of gene transfer into the disc and the therapeutic potential of enhancing matrix proteins.
Kang has performed more than 14,000 spinal surgeries. He has authored over 300 peer-reviewed publications and more than 73 book chapters. He has served as deputy editor of Spine as well for the spine section of the Journal of Orthopaedic Research (JOR).
In August 2025, he co-authored Sex Disparities in Spine Surgeon Leadership of Clinical Trials for Degenerative Spine Disease Research, a study assessing the representation of women as principal investigators in spine surgery clinical trials. He published Shifts in Diversity Along the Spine Surgery Training Pathway, a cross-sectional analysis examining racial, ethnic, and gender diversity among academic orthopedic spine surgeons in the United States.
In 2024, Kang explored translational therapies in Rapamycin Mitigates Inflammation-Mediated Disc Matrix Degradation, investigating the potential of rapamycin to regulate the PI3K/Akt/mTOR signaling pathway and counteract inflammation-induced disc degeneration.
Selected publications
Kang JD, Stefanovic-Racic M, McIntyre L, et al. "Towards a Biochemical Understanding of Human Intervertebral Disc Degeneration and Herniation: The Contributions of NO, Interleukins, PGE2, and MMPs." Spine, 22:1065-1073, 1997.
Vo N, Seo HY, Robinson A, et al. "Accelerated Aging of Intervertebral Discs in a Mouse Model of Progeria." J Orthop Res 2010; 28(12):1600-7.
Nishida K, Kang JD, Gilbertson LG, et al. "Modulation of the Biological Activity of the Rabbit Intervertebral Disc By Gene Therapy." Spine, 24:2419-2425, 1999.
Leckie S, Bechara B, Hartman R, et al. "Injection of AAV2-BMP2 and AAV2-TIMP1 into the nucleus pulposus slows the course of intervertebral disc degeneration in an in-vivo rabbit model." The Spine Journal, 12(1):7-20, 2012.
Massaad, Elie; Mitchell, Taylor S.; Duerr, Emmy; Kiapour, Ali; Cha, Thomas D.; Coumans, Jean-Valery C.; Groff, Michael W.; Hershman, Stuart H.; Kang, James D.; Lipa, Shaina A.; Small, Lianne; Tobert, Daniel G.; Schoenfeld, Andrew J.; Shankar, Ganesh M.; Zaidi, Hasan A. (2024-04-18). "Disparities in Surgical Intervention and Health-Related Quality of Life Among Racial/Ethnic Groups With Degenerative Lumbar Spondylolisthesis". Neurosurgery. 95 (3): 576–583. doi:10.1227/neu.0000000000002925. ISSN0148-396X. PMID39145650.
Silvestre, Jason; Kang, James D.; Ravinsky, Robert A.; Lawrence, James P.; Reitman, Charles A. (2024). "Establishing case volume benchmarks for ACGME-accredited orthopedic surgery of the spine fellowship training". The Spine Journal. 24 (8): 1495–1501. doi:10.1016/j.spinee.2024.03.014. ISSN1529-9430. PMID38554735.
Mizuno, Shuichi; Vadala, Gianluca; Kang, James D. (2024). "Biological Therapeutic Modalities for Intervertebral Disc Diseases: An Orthoregeneration Network (ON) Foundation Review". Arthroscopy: The Journal of Arthroscopic & Related Surgery. 40 (3): 1019–1030. doi:10.1016/j.arthro.2023.10.032. ISSN0749-8063. PMID37918699.