Results of Hallux Metatarsophalangeal Joint Arthrodesis with and without Calcaneus Autograft

CATEGORY: Bunion; Midfoot/Forefoot; Other INTRODUCTION/PURPOSE: Hallux rigidus is the most common degenerative arthropathy of the foot. Primary hallux metatarsophalangeal (MTP) joint arthrodesis is the most common surgical treatment for end-stage hallux rigidus and can also be utilized for correction of hallux valgus. Though satisfaction rates following hallux MTP joint arthrodesis are very favorable, nonunion rates have been reported as high as 12%. Many surgeons use orthobiologics and/or autograft to augment arthrodeses about the foot and ankle in an effort to increase union rates. The purpose of this study is to retrospectively compare union rates of hallux MTP joint arthrodesis with and without calcaneus autograft. METHODS: A query of our institution’s administrative database was performed to identify patients who underwent a primary hallux MTP joint arthrodesis between February 2016 and February 2019. We compared patients who underwent arthrodesis with and without calcaneus autograft. Surgeon preference dictated use of autograft, as some in our group routinely use graft while others do not. Patients 18 years and older who underwent a primary hallux MTP arthrodesis were included. Patients were excluded if they had radiographic evidence of significant bone loss or if allograft or biologic therapies were used. Patient charts and final radiographs were reviewed. The primary outcome was successful union of the hallux MTP joint arthrodesis. Secondary outcomes included preoperative diagnosis, type of surgical fixation and surgical complications. Data was compared using a student T-test. RESULTS: There were 336 feet included in the final analysis, and 140 underwent hallux MTP arthrodesis with calcaneus autograft. Mean follow-up time was 14.8 weeks. Among all patients, 89.9% had a successful union. There was no difference in union rates between those who underwent arthrodesis with calcaneus autograft (87.9%) compared to without autograft (91.4%; p = 0.302). Hallux valgus was the preoperative diagnosis in 52.7% of cases followed by hallux rigidus (39.9%). The most common fixation method was a lag screw with a dorsal plate (80.5%). Painful hardware was the next most common complication (8.6%), and smoking and diagnosis of diabetes demonstrated no effect on union rates. In the autograft group, there were no complications related to the calcaneus autograft donor site. CONCLUSION: As orthobiologics and local bone autograft gain popularity in foot and ankle surgery, it is important to report clinical outcomes and establish evidence-based guidelines for use. In this relatively large retrospective comparison, the use of calcaneal graft was noted to be safe (no complications from graft site). However, there was no difference in union rate when comparing hallux MTP arthrodesis with and without calcaneus autograft.