Does preoperative radiological alignment affect outcomes after total knee replacement? – Clinical, Radiological and Functional assessment

Presenting Author- Sahil Sanghavi
Purpose – To study the relationship between pre-operative radiological alignment and outcomes after TKR. Materials and Methods – All patients with osteoarthritis and rheumatoid arthritis of knees were included in the study. Cases excluded from the study were revision TKR, knees with pre-operative peri-articular fractures, knees with extra-articular deformities and neuropathic joints. Patients were divided into three groups depending upon the pre-operative radiological alignment i.e. varus, neutral or valgus. Mechanical axes were measured preoperatively and at 1- year follow-up. Outcome measures were the Knee Society Clinical Rating System, WOMAC score, the Oxford Knee Score and SF-36 questionare. Observations and results – Total 350 patients with a mean age of 65.4 were included in the study. Restoration of normal mechanical axis resulted in significant improvement in post-operative functional scores. Improvement was noted in single leg stance time, walking distance, pain VAS score and ADLs. However the improvement was uniform in varus, valgus and neutral groups. Conclusion - Pre-operative mechanical axis malalignment adversely affects the walking distance and single leg stance time, however these parameters improved following TKR with restoration of normal mechanical axis. The outcomes after TKR showed significant improvement irrespective of pre-operative varus or valgus deformities. In other words outcomes were similar in varus, valgus and neutral groups post TKR with restoration of normal mechanical axis.