Background: The dorsal bunion deformity consists of the elevation of first metatarsal head, plantar flexion contracture at the first metatarsophalangeal joint, and dorsiflexion contracture of the tarsometatarsal joint. A reverse Jones procedure with transfer of the flexor hallucis longus to the metatarsal head has been an effective method in correcting this deformity. Methods: This is a retrospective review of 27 patients with 33 feet who had reverse Jones procedure with or without metatarsal osteotomy between 1983 and 2002. All patients had previous soft tissue releases for clubfoot deformity. Clinical reviews included muscle function test and radiographic evaluation before and after procedures. We used the American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-interphalangeal scale for functional outcome results. Results: The average follow-up was 4.96 years. There were 21 boys and 6 girls. Average age at time of procedure was 13.7 years. With the reverse Jones procedure, there were 18 first metatarsal osteotomies and 12 split anterior tibial tendon transfers. Before surgery, decreased muscle strength in triceps surae (73%), tibialis posterior (76%), peroneus longus (67%), and extensor hallucis longus (76%) was noted. Patients (84.9%) had normal tibialis anterior and flexor hallucis longus power. In radiographic evaluations, the operation resulted in decreased elevation of the first metatarsal by measuring the metatarsalhorizontal angle. The lateral metatarsophalangeal angle improved from 23 degrees plantar flexion to 1 degree in dorsiflexion. The average global American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-interphalangeal score was 70 preoperatively and 92 postoperatively with improvement of subscores in pain, activity, footwear, range of motion, callus, and alignment. Conclusions: Dorsal bunion is a recognized long-term complication after clubfoot surgery. The causes of the deformity are weakness of Achilles tendon, overpowering of flexor hallucis longus, and strong anterior tibial tendon with weakness of peroneus longus. The reverse Jones procedure improved the condition in this series and provided a long-lasting and effective correction of the dorsal bunion deformity.
Date:
2007-10
Relation:
Journal of Pediatric Orthopaedics. 2007 Oct-Nov;27(7):814-820.