Abstract
Fusion remains the standard of care and is associated with a high satisfaction rate. But.… fusion generally requires 6 weeks of restricted weight bearing or immobilization. Potential problems include 1) nonunion, 2) malunion, 3) sesamoid pain (from DJD), 4) late onset IP1 DJD.
Complete joint replacement has been performed with a number of different designs since the early 1970's. The metal and poly designed implants are associated with a high failure rate, presumably from high shear loads, eccentric axial loads, poor fixation and bone stock problems. Resurfacing of both sides of the joint with a one piece silicone based crosslinked rubber {“silastic”} in rheumatoid patients appears to function better with use of metal grommets to reduce generation of particle debris and foreign body reaction. These silastic implants are still used by surgeons in select low-demand rheumatoid patients. Salvage after failure of any of these total joint replacements can be challenging because of loss of bone stock.
3 other methods are used to resurface the joint in severe OA: 1) resurfacing the proximal phalangeal side only, 2) resurfacing the metatarsal head only and 3) resurfacing the joint with and interposition arthroplasty. 1) advantage of the proximal phalangeal side resurfacing is simplicity of geometry; the disadvantage is disruption of the FHB attachment and the relative scarcity of severe cartilage damage at that side of the joint. 2) Advantage of the metatarsal head side for resurfacing is that is the typical location of the arthritic change; the disadvantage is potential interference with the sesamoid complex and bulkiness of fixation could lead to a more difficult salvage. 3) The advantage of interposition arthroplasty is the maintenance of bone stock; disadvantages include inconsistent local tissue and somewhat less predictable outcomes.
In this talk I will focus primarily on the technique and results of a proximal phalangeal resurfacing approach for OA of the MTP1 joint.
