Proximal Fibular Osteotomy: Is it Really an Option for Medial Compartmental Osteoarthritis Knee? Our Experience at Tertiary Centre.

Introduction: The medial compartment is commonly involved in age-related osteoarthritis knee because weight-bearing axis passes close to the medial condyle and its large surface area. Various treatments have been proposed ranging from conservative to total knee arthroplasty which is an expensive and complex treatment. Recently, proximal fibular osteotomy (PFO) for medial compartment knee osteoarthritis became popular as a treatment modality. Although, the mechanism of PFO is not clear. So, we conducted a prospective study to assess the clinico-radiological outcome of proximal fibular osteotomy in medial compartment osteoarthritis knee.

Materials And Methods: We conducted a prospective study from November 2017 to November 2019 on 32 (47 knees) patients with degenerative medial compartmental osteoarthritis knee, varus deformity < 15 and Kellgren and Lawrence grade II and grade III (K-L Grade). We recorded the visual analogue score (VAS) and knee society score (KSS) pre-operatively and post-operatively of all patients.  We got weight bearing anterio-posterior and lateral radiograph of knee done. We assessed joint space ratio and lateral tibio-femoral angle (FTA) pre-operatively, post-operatively and at each follow-up.

Results: Mean age was 48.4 (35-65) years and the mean follow-up was 18 months. Mean duration for unilateral PFO was 37 min and for bilateral, 55 min. The VAS was improved from 7.33 ± 0.72 to 7.13 ± 1.64 at 3 months and remained the same at final follow-up ( > 0.05). The mean pre-operative clinical and functional KSS was statistical insignificantly improved at 3 months and final follow-up ( > 0.05). The mean pre-operative lateral and mean pre-operative joint space ratio was also improved statistically insignificant ( > 0.05). Extensor hallucis longus (EHL) weakness was documented in five knees (10.6%) and paraesthesia was documented in seven (14.8%) knees.

Conclusion: Although, PFO is a simple, less invasive and affordable procedure, we could not reproduce the favourable results in medial compartmental osteoarthritis knee. This procedure is also associated with reversible but noticeable complications. So, we would not consider PFO as an alternative option in the treatment of medial compartmental osteoarthritis knee.