Abstract

Background: Total knee arthroplasty (TKA) is one of the most common surgical procedures in orthopaedics. The aim of TKA is to achieve long-term implant survival and successful functional outcome with minimal complications and cost effectiveness. The aim of the study is to evaluate soft tissue balance at midflexion in addition to routine balancing of knee at extension and 90° flexion before and after placing final prosthetic components in total knee arthroplasty and to assess and look for reasons of variability of soft tissue balance at midflexion compared to balancing at full extension and 90° flexion.
Methods: Aprospective study of maximum of 20 patients coming to the department of orthopedics in teaching hospitals attached to AIIMS Patna, was done. Patients who are undergoing primary total knee arthroplasty for osteoarthritis knee and rheumatoid arthritis of knee were included. Patients with traumatic arthritis of knee, extensor mechanism dysfunction, vascular disease of lower limbs, recurvatum deformity of knee, remote source of infection were excluded. Posterior Stabilized Total Knee Replacement (Zimmer Knee) Prosthesis is used in all cases. The anterior fibers of MCL and ITB were preserved in all cases.
Conclusion: Significant improvement in knee function can be achieved with total knee replacement in a well balanced knee. Lateral laxity is commonly observed than medial laxity in midflexion, more common in early range of flexion (between extension and midflexion). Midflexion stability is not influenced by component sizes. Post operative function of weight transfer and climbing up and down the stairs is better with knees balanced in midflexion. Preserving anterior fibers of MCL and ITB is essential technique for obtaining midflexion stability.