Postoperative Outcomes and Complications in Hallux Rigidus: A Comparison Between Polyvinyl Alcohol Implant and Cheilectomy with Moberg Osteotomy

CATEGORY: Midfoot/Forefoot; Other INTRODUCTION/PURPOSE: In 2016, the US Food and Drug Administration (FDA) approved the use of a polvinvyl alcohol (PVA) hydrogel implant (Cartiva, Elmsford, NY) for surgical treatment of hallux rigidus, or degenerative arthritis of the first metatarsophalangeal (1st MTP) joint. While studies have demonstrated the safety and usability of PVA implant, clinical outcomes following hemiarthroplasty with the PVA have not yet been compared to that of traditional joint-preserving procedures such as cheilectomy with Moberg osteotomy in the treatment of hallux rigidus. The purpose of this study is to compare patient-reported outcomes and postoperative complications between PVA hemiarthroplasty and cheilectomy with Moberg osteotomy, with the hypothesis that the addition of PVA would result in superior clinical outcomes. METHODS: Patients were retrospectively identified who underwent hallux rigidus correction by one of seven Foot and Ankle fellowship-trained orthopaedic surgeons between March 2016 and November 2018. Out of 162 patients, a total of 133 patients constituted our study cohort after excluding patients with insufficient follow-up. Of the 133, 60 patients (mean age 57.2 years) were treated with combination PVA, cheilectomy, and Moberg osteotomy (PCM) and 73 patients (mean age 54.1) were treated with cheilectomy and Moberg (CM) alone. Both preoperative as well as minimum 1-year postoperative patient-reported outcome scores (PROMIS) were compared between the two cohorts. Chart review was performed to compare rates of revision and complications. RESULTS: Average time to follow-up was 14.5 months for PCM and 15.6 for CM groups. Both PCM and CM cohorts demonstrated significant improvement in PROMIS scores, with the CM group demonstrating significantly greater increase in Physical Function (7.14 +- 8.48 vs 3.58 +- 6.24, p=0.01). While preoperative scores were comparable, postoperatively the CM group had a significantly higher average Physical Function (51.8 +- 8.7 vs 48.8 +- 8.0, p=0.04) and lower Pain Intensity (39.9 +- 8.3 vs 43.4 +- 8.7, p=0.02). There were 2 cases of revision with re-implantation and 1 case of conversion to arthrodesis in the PCM group. There was 1 case of conversion to PVA in the CM group. Three patients who underwent PCM had a documented postoperative infection requiring antibiotics. CONCLUSION: Our data suggests that the addition of polyvinyl alcohol implant in the treatment of hallux rigidus results in significant improvement in patient-reported outcomes. However, patient-reported physical function may not be up to par at minimum 1-year follow-up compared to cheilectomy and Moberg osteotomy alone. In addition, while incidence was low in our cohort, revision of the implant as well as conversion to arthrodesis remain possible complications of PVA. Therefore, we believe that proper patient selection is recommended when considering surgical treatment options for hallux rigidus.