Long-term functional results of first metatarsophalangeal joint arthrodesis for hallux rigidus

Introduction First metatarsophalangeal joint (MTPJ) osteoarthritis hallux rigidus (HR) is the most common arthritic condition in the foot and occurs in 2.5-7.8 % of the population over 50 years. First MTPJ arthrodesis is currently considered to be the gold standard for the treatment of end-stage HR. When treating the advanced stage of HR, arthrodesis has long been established as an effective surgical procedure providing very predictable and satisfying results. Although the surgical authors prefer joint-sparing procedures first MTPJ fusion when required is the joint destructive procedure of choice in severe HR to eliminate or minimize pain, stabilize the first MTPJ and allow the hallux to bear weight. Functional outcomes achieved with fusion are also consistent with those from other surgical procedures. The purpose of this study is to evaluate long-term functional outcomes of first MTPJ arthrodesis. Material and methods Clinical and functional outcomes of MTPJ arthrodesis performed for 19 patients (25 feet) with grade 3 or 4 HR using the Coughlin and Shurnas Classification System between September 2010 and December 2017 were reviewed. The patients' mean age was 60 years (range, 35 to 86 years). The median interval between surgery and the last follow-up was 5 years (interquartile range, 1.5 to 8 years). Ultimately, outcome assessment relied on patient satisfaction, radiographic examination, visual analogue scale (VAS), the American Orthopaedic Foot & Ankle Society (AOFAS) and the Foot and Ankle Ability Measure (FAAM) scores. Results AOFAS score was rated as good in 92 % of the cases (23/25), as fair in 8 % (2/25) with neither excellent nor poor results recorded. The median AOFAS score increased from preoperative 43.0 to postoperative 85.0 that was statistically significant (p < 0.05). Postoperative median FAAM Activities of Daily Living (ADL) was 99 %, median subjective ADL was 90 %, median FAAM sport was 84 %, and median subjective sport was 80 %. Patient subjective assessment was scored as "excellent" in 36 % of cases (9/25), "good" in 56 % (14/25), "fair" in 8 % (2/25) with no "poor" results recorded. The median VAS pain score decreased from 6 at baseline to 1 point postsurgery (p < 0.05). Conclusion First MTPJ arthrodesis was shown to be a very effective, reliable and lasting primary procedure for severe HR that provided 92% of good outcomes in our series. The procedure can be advocated as a predictable and excellent option for Coughlin and Shurnas grades 3 and 4 HR facilitating high success rates in pain relief and restoration of function. © 2020 lchenko D.V., Korolev A.V., Kardanov A.A.