Interpositional arthroplasty with Dx Reinforcement Matrix®: A possible solution in the surgical treatment of lateral TMT joints arthritis

There are two main categories of surgical management for lateral TMT joints arthritis: fusion and motion preserving surgeries, which include resection arthroplasty, tendon interpositional arthroplasty and ceramic interpositional arthroplasty. This article reports the first case of interposition arthroplasty of the 5th TMT joint with Dx Reinforcement Matrix®, a porcine dermal extracellular matrix.We present the case of a 22-year-old male who suffered a motorcycle accident which caused closed fractures of the 2nd, 3rd and 4th metatarsal diaphysis, an articular fracture of the 5th metatarsal base and an impaction fracture of the cuboid distal articular surface. Two years later, he presented pain in the lateral aspect of the midfoot and the radiographs and CT scan showed impaction of the fifth metatarsal base in the cuboid, with post-traumatic arthritis of the 5th TMT joint. An interposition arthroplasty of the 5th TMT joint with a porcine acellular dermal extracellular matrix (Dx Reinforcement Matrix® – Arthrex), was performed. At 3 years follow-up, the patient was asymptomatic, had a symmetric mobility comparatively to the contralateral foot and an AOFAS Midfoot scale of 100/100.From a biomechanical point of view, fusion of the lateral TMT joints seems less desirable due to the motion of the lateral column. Motion preserving surgeries have been described, with small case series and equivalent satisfactory results. We presented the case of a young patient with isolated lateral TMT joint arthritis and reported the first case of interposition arthroplasty with Dx Reinforcement Matrix® with a good clinical result at 3 years follow-up.