Abstract
TMTJ fusion is performed for arthritis or painful deformity. K-wire and trans-articular screws are usually used to stabilize the joints. We present our experience with LP for TMTJ fusion in first 100 joints.
Patients and methods
100 TMTJ in 74 patients were fused and stabilised with LP between January 2007 and December 2010. The indication was Lisfranc arthritis and hallux valgus. Iliac crest bone autograft was used in 64 joints. Auto graft was used in 22/53 first TMT fusions. All patients post-operatively had below knee plaster immobilization and protected weight bearing walking for first 6 weeks. Clinical and radiological surveillance continued until bone. AOFAS midfoot scale was used as outcome measure.
Results
There were 18 male and 56 female patients with average age of 51 (14 -68). AOFAS midfoot scale improved 42% for pain, 30% for function and 53% for alignment. Average AOFAS overall score improved from 30 pre-op to 67 post op.
95 joints had clinical and radiological fusion. 1 patient needed removal of metalwork and 3 had delayed wound healing and 4 had radiological non- . All non- s were in 1st TMTJ where bone graft failed and were revised. None of the lesser ray TMTJ had non- . Average satisfaction score was 7 out of 10. 86% said they would recommend it to a friend and 91% would have it again.
Discussion
Biomechanical studies has shown plates are not as strong or stiff as trans-articular screw fixation however they are easy to use, have more flexibility and act as a buttress for autograft. Our results show that dorsal locking plate has satisfactory clinical out come with or without bone graft for lesser rays. 1st TMT fusion without bone graft has higher fusion rate compare to 3 failures in 22 1st TMTJ with bone graft. This is due to multiple factors including LP being not strong enough to sustain the stresses until creeping substitution through the bone graft.
Conclusion
Locking plates provide satisfactory stability without complications for lesser ray with or without bone graft. Fusion for 1st TMTJ with auto bone graft has high failure of 13%.
