Outcome of total knee replacement in advanced osteoarthritis knee with posteromedial bone defect

Introduction: OA in its late stages is characterized by serious joint tissue deterioration and possible bone loss and deformities. Non-contained posteromedial bone defect is a challenge in Primary total knee replacement (TKR) due to the issue with implant stability and placement. Each of these defects needs special attention if there is to be a desired outcome. The management plan of TKR in these patient populations is to provide relief from pain, regain the function of the affected joint, and minimize its further degradation. Objectives: To assess the functional and clinical results of Primary TKR in patients with advanced osteoarthritis of the knee presenting with posteromedial bone loss. Materials and Methods: A descriptive case series study of 25 patients with advanced OA and non-contained posteromedial bone defects was included in this study from Jan 2021 to December 2023. For bone defect, an autologous bone graft from a tibial cut was utilized and fixed with two fully threaded cortical 3.5 mm screws. Then, the tibial stem was used for load sharing across the tibial bone to increase stability, and cemented prostheses were used for routine Primary TKR. Quantitative data of pre- and post-operative functional scores were collected and then compared statistically to assess the degree of improvement. Results: With respect to functional outcome, the mean pre-operative knee society score (KSS) was 42.3 ± 5.7, and the mean post-operative KSS was 85.4 ± 6.1 (P < 0.001). Post-operative, mean flexion of 115 ± 8. Mean pain relief and joint stability scores demonstrated statistically significant improved results. Two patients had superficial surgical site infections, which were then resolved with debridement and antibiotics. Conclusion: Surgical reconstruction of bone defect with autologous bone graft with primary TKR in patients with advanced OA with posteromedial bone defects is an approach to lessen the quantity and burden of hardware, resulting in low cost and satisfactory function, pain relief, and overall improvement in the gait. Keywords: Total knee replacement, Osteoarthritis, Non-contained bone defect, Bone reconstruction, Tibial stem, Posteromedial bone defect.