ObjectiveTo explore the surgical technique and effectiveness of sliding osteotomy of medial femur condyle in handling soft tissue balance of severe valgus deformity in total knee arthroplasty (TKA). MethodsBetween June 2008 and February 2014, 18 cases (19 knees) of severe valgus knees undergoing sliding osteotomy of medial femur condyle in primary TKA were included. Of the 18 patients, 6 were male and 12 were female with an average age of 52.3 years (range, 29-72 years), including 3 cases (3 knees) of osteoarthritis, 11 cases (12 knees) of rheumatoid arthritis, 3 cases (3 knees) of post-traumatic arthritis, and 1 case (1 knee) of deformities in skeletal dysplasia. Before surgery, the tibial-femur angle (TFA) was (33.0±2.9)°; the Hospital for Special Surgery (HSS) score was 41.6±7.7; the Knee Society Score (KSS) lateral stability score was 6.0±5.4. All cases were rated as type II according to Krackow classification of valgus knee. During primary TKA, sliding osteotomy of medial femur condyle was performed via a medial parapatellar approach. ResultsIncision healed by first intention in all cases. Peroneal nerve palsy occurred in 1 patient, which was cured after 6 months of conservative treatment. Eighteen cases were followed up 19 months to 7 years, with an average of 5.7 years. All patients had no complications of deep vein thrombosis, deep infection, and prosthesis loosening. X-ray films showed that bone healing was achieved in all cases at 6 months. At last follow-up, the TFA was (4.8±1.8)°, showing significant difference when compared with preoperative value (t=62.61, P=0.00). The HSS score was 87.2±10.5 and the KSS lateral stability score was 12.4±3.1, all showing significant differences when compared with preoperative scores (t= —33.35, P=0.00; t= —6.83, P=0.00). ConclusionSliding osteotomy of medial femur condyle is effective for correcting severe valgus knee deformity during TKA. Satisfactory joint function and stability may be achieved.
Objective To explore the effectiveness and failure causes of large-head metal-on-metal total hip arthroplasty (large-head MoM THA). Methods Between March 2007 and May 2010, 159 patients (183 hips) underwent large-head MoM THA, and the clinical data were analyzed. There were 50 females (54 hips) and 109 males (129 hips) with an average age of 50 years (range, 20-78 years). Single hip was involved in 135 cases (left hip in 69 cases and right hip in 66 cases) and double hips in 24 cases. The causes included femoral head necrosis in 74 cases (93 hips), Legg-Calve-Perthes in 1 case (1 hip), osteoarthritis in 18 cases (19 hips), developmental dysplasia of the hip in 17 cases (18 hips), osteoarthritis after hip septic infection in 8 cases (8 hips), traumatic arthritis of the hip in 6 cases (6 hips), femoral neck fracture in 17 cases (17 hips), ankylosing spondylitis in 8 cases (11 hips), rheumatoid arthritis of hip in 9 cases (9 hips), and adult onset Still’s disease in 1 case (1 hip). Before operation, visual analogue scale (VAS) was 6.59±0.87; Harris score was 45.99±8.07. Results Healing of incisions by first intention was achieved, and no operative complication occurred. The patients were followed up 1.2-8.2 years (mean, 6.1 years). Implant failure was observed in 15 cases (17 hips), and the 5-year survival rate of large-head MoM THA was 91.80% (168/183). The causes of implant failure after THA were inflammatory pseudotumor in 4 cases (4 hips), acetabular aseptic loosening in 3 cases (3 hips), osteolysis in 4 cases (5 hips), acetabular aseptic loosening combined with inflammatory pseudotumor in 3 cases (3 hips), and functional disused in 1 case (2 hips). Of them, 9 cases (11 hips) did not receive revision surgery for various reasons, while 6 cases (6 hips) underwent revision surgery at 1.2-5.4 years (mean 3.7 years) after large-head MoM THA. At last follow-up, VAS and Harris score were 1.72±1.48 and 81.37±10.75 respectively, showing significant differences when compared with preoperative scores (t=–35.547，P=0.000；t=33.823，P=0.000). The function was excellent in 44 hips, good in 89 hips, fair in 33 hips, and poor in 17 hips. Conclusion Large-head MoM THA has a high revision rate during mid- and long-term follow-up because of inflammatory pseudotumor, acetabular aseptic loosening, and osteolysis. Early revision can effectively improve the function of the hip and improve patients’quality of life.