Outcomes of the Distal Metatarsal Dorsiflexion Osteotomy for Advanced Hallux Rigidus.

ABSTRACT

BACKGROUND: Hallux rigidus can be treated using several different methods and the best treatment option depends on the severity of degenerative changes of the metatarsophalangeal (MTP) joint. However, the ideal operative option for advanced hallux rigidus remains debatable. This prospective study was performed to evaluate the intermediate-term clinical outcomes of distal metatarsal osteotomy used as a joint-preserving method for the treatment of advanced hallux rigidus. METHODS: Forty-two cases (39 patients) were followed for more than 3 years after distal metatarsal dorsiflexion osteotomy for advanced hallux rigidus of grade III-IV. Clinical evaluations included the American Orthopaedic Foot & Ankle Society (AOFAS) scores, Foot and Ankle Ability Measure (FAAM) scores, and patient subjective satisfaction scores. Range of motion (ROM) of great toe, complications, reoperation rates, width of the MTP joint space, and times to union were evaluated. RESULTS: Mean AOFAS hallux and mean FAAM scores significantly improved from 56.4 and 61.2 points preoperatively to 87.6 and 88.7 points at final follow-up, respectively ( P < .001). Grade III and IV groups had significantly different AOFAS and FAAM scores at final follow-up. Mean dorsiflexion of great toe significantly improved from 14.8° preoperatively to 35.5° at final follow-up ( P < .001). Mean patient satisfaction score at final follow-up was 92.8 points. There were 4 cases (9.5%) of subsequent fusion and 2 cases (4.8%) of transfer metatarsalgia. CONCLUSIONS: Distal metatarsal dorsiflexion osteotomy using bio-compression screws appears to be an effective operative option for grade III advanced hallux rigidus with viable cartilage on >50% of the first metatarsal articular surface, as it restored joint motion, provided reliable pain relief, and did not require implant removal. However, based on the unsatisfactory clinical results and the high rate of reoperation observed, the authors cannot recommend this operative method for the treatment of end-stage (grade IV) hallux rigidus. LEVEL OF EVIDENCE Level IV, prospective case series.