Metatarsal head resurfacing hemiarthroplasty in the treatment of advanced stage hallux rigidus: outcomes in the short-term.

OBJECTIVE: The aim of this study was to evaluate the short-term outcomes of metatarsal head metal resurfacing hemiarthroplasty in patients with advanced stage hallux rigidus.

METHODS: The study included 14 feet (4 left, 10 right) of 12 patients (10 female, 2 male; mean age: 63 ± 5; range: 55 to 71 years) who underwent metatarsal head metal resurfacing hemiarthroplasty (HemiCAP(®)) between 2007 and 2010. Additionally, capsular release and periarticular osteophyte debridement were performed. Staging was made according to Coughlin and Shurnas' clinical and radiological grading system. Hallux valgus and intermetatarsal angles were measured using pre and postoperative standing AP and lateral foot views. Clinical assessment was made with first metatarsophalangeal joint range of motion, the AOFAS (American Orthopaedic Foot and Ankle Society) hallux metatarsophalangeal-interphalangeal scale and satisfaction level.

RESULTS: Mean follow up was 19.5 (range: 14 to 26) months. Two patients had bilateral involvement. According to Coughlin and Shurnas' clinical and radiological grading system, nine feet were Stage 3 and five feet were Stage 4. According to the AOFAS scale, results of eight feet (57.1%) were excellent, four feet (28.6%) were good and two feet (14.3%) were moderate. Mean total AOFAS score increased by 26.2 points postoperatively (p<0.05). Mean range of motion of the first metatarsophalangeal joint improved significantly from a preoperative 22.2 ± 5.6 (range: 10 to 28) degrees to a postoperative 56.3 ± 9.6 degrees (p<0.05). Mean hallux valgus angle decreased from a preoperative 14.3 (range: 9 to 17) degrees to a postoperative 11.1 (range: 4 to 13) degrees and the mean intermetatarsal angle increased from a preoperative 10.5 (range: 8 to 14) degrees to a postoperative 10.8 (range: 8 to 15) degrees. Patient satisfaction levels were very good in 10 feet (71.4%), good in 3 (21.4%), and moderate in one (7.2%). Complications included metatarsalgia aggravated by long walks in one patient and hypoesthesia of the great toe in three patients. Push-off power of the great toes was measured as 4/5 in three cases, and 5/5 in others.

CONCLUSION: Metatarsal head metal resurfacing hemiarthroplasty provides high patient satisfaction level and good functional outcome in the short-term, in the surgical treatment of advanced stage hallux rigidus refractory to conservative treatment options.