Modified Oblique Keller Capsular Interposition Arthroplasty for Hallux Rigidus

INTRODUCTION: This paper describes the modified oblique Keller capsular interposition arthroplasty, which may be indicated for patients with late-stage hallux rigidus who wish to retain joint motion. STEP 1 EXPOSURE: Make dorsal medial longitudinal incision over MTP joint and retract dorsal cutaneous nerve of great toe laterally. STEP 2 MOBILIZE EXTENSOR HALLUCIS LONGUS TENDON: Separate extensor hallucis longus from dorsal aspect of capsule and extensor hallucis brevis and retract laterally. STEP 3 MOBILIZE DORSAL ASPECT OF CAPSULE AND EXTENSOR HALLUCIS BREVIS TENDON: Leave inferior half of medial aspect of capsule attached to first metatarsal head to prevent late hallux valgus drift; make the capsular flap as long as possible. STEP 4 PERFORM DORSAL CHEILECTOMY AND RESECT PORTION OF BASE OF PROXIMAL PHALANX TO DECOMPRESS JOINT: The greater the preoperative stiffness, the more bone needs to be removed from the phalanx base. STEP 5 INTERPOSE CAPSULE AND SUTURE CAPSULE TO MTP PLANTAR PLATE: Advance the dorsal aspect of the capsule over the metatarsal head and suture it into the plantar plate with absorbable suture in an interrupted fashion. STEP 6 IMBRICATE MEDIAL ASPECT OF CAPSULE: Imbricate the medial aspect of the capsule with absorbable suture to hold the toe in a corrected position. STEP 7 CLOSE WOUND AND APPLY SUPPORTIVE DRESSING: Perform layered closure and apply forefoot compression dressing. STEP 8 POSTOPERATIVE CARE: Patient performs active range-of-motion exercises of great-toe MTP and IP joints, intrinsic muscle strengthening, and scar massage. RESULTS: We compared a cohort of patients who had the modified oblique Keller capsular interposition arthroplasty (MOKCIA) with a group who had an arthrodesis of the first MTP joint. WHAT TO WATCH FOR: IndicationsContraindicationsPitfalls & Challenges.