First Metatarsophalangeal Arthrodesis for Hallux Rigidus and Hallux Valgus: A Comparison of Patient Reported and Clinical Outcomes.

Few prior studies have compared the patient reported outcomes of first metatarsophalangeal arthrodesis between hallux rigidus and hallux valgus patients. Furthermore, we sought to examine the impact of postoperative radiographic hallux alignment on outcomes scores within each group. A retrospective review of 98 patients who a received primary metatarsophalangeal arthrodesis from January 2010 to March 2020. Clinical complications including nonunion were collected. Patient Reported Outcomes Measurement Information Systems (PROMIS) Physical Function, PROMIS Pain Interference, and the foot function index (FFI) revised short form scores were obtained via telephone. Patients were grouped based on review of preoperative radiographs of the foot and this grouping 37 hallux rigidus and 61 hallux valgus patients. Clinical and patient reported outcomes were compared between these pathologies. No differences in the rate of wound complications, radiographic union, and revision surgery were found between the 2 subgroups. At a median of 2.4 years (3.9 IQR) postoperatively, PROMIS and FFI scores did not vary by pathology group. For both groups, PROMIS scores were similar to the general population of the United States. The postoperative first MTP dorsiflexion angle in the hallux rigidus group was correlated with decreased FFI Pain, FFI Total, and PROMIS Pain Interference domain scores (|r| ≥ 0.40, p < .05 for all). When performing MTP arthrodesis in patients with hallux rigidus, increasing the first MTP dorsiflexion angle may correlate with improved intermediate term patient reported outcomes. However, further studies will need to be done to confirm this theoretical relationship.