Is Interposition Arthroplasty a Viable Option for Treatment of Moderate to Severe Hallux Rigidus? A Systematic Review and Meta-analysis

Category: Midfoot/Forefoot Introduction/Purpose: Hallux rigidus is a painful arthritis of the first metatarsophalangeal joint that causes progressive loss of mobility. Treatment options include activity modifications, analgesics, corticosteroids, and surgery. Arthrodesis of the MTP joint is considered the gold standard treatment for hallux rigidus, but it is often reserved for advanced. Interposition arthroplasty uses a spacer taken from an autograft, allograft, or synthetic material. For patients with severe arthritic diseases who would like to preserve MTP joint function, interposition arthroplasty may be a viable option. The purpose of this systematic review is to investigate patient outcomes after undergoing interposition arthroplasty of the MTP joint. The objectives are to determine if this technique is practical for patients who would prefer to avoid arthrodesis, and to systematically analyze post-operative improvement. Methods: The systematic review was performed following PRISMA (Preferred Reporting Items for Systematic Review and Meta-analyses) guidelines. Medline, pubmed, Embase, and Cohrane Database of Systematic Reviews (CDRS) were searched for publications from 2000 to 2017. Duplicates were then removed, and titles and abstracts were reviewed to confirm the relevance f the study. Studies were included if they reported results of first MTP joint interposition arthroplasty in one of the well-known scoring systems: AOFAS, FFI, or SF-36. Studies also were also required to have a 12 month follow up. Systematic review and data extraction were performed on all selected studies. Means were recorded and placed in tables for all variables including scoring results and complication rates. A linear regression model comparing the change in preoperative to postoperative AOFAS scores between the autogenous versus allogenous interposition materials was performed. Results: Database searches produced 574 articles for review. 15 of these were included in the systematic review. Mean AOFAS score was improved from 41.35 preoperatively to 83.17 postoperatively. Mean pain, function, and alignment scores improved from preoperative values of 14.9, 24.9, and 10 to postoperative values of 33.3, 35.8, and 14.5. Mean dorsiflexion increased from 21.27 degrees (5-30) to 42.03 degrees (25-71). Mean ROM improved from 21.06 to 46.43 degrees. Eighty-seven percent of patients were satisfied to highly satisfied with their surgery and would choose surgery again. Joint space increased by 0.8 mm to 2.5 mm. The most common complications included metatarsalgia (13.9%), loss of ground contact (9.7%), osteonecrosis (5.4%), great toe weakness (4.8%), hypoesthesia (4.2%), decreased push off power (4.2%), and callous formation (4.2%). Conclusion: The management of hallux rigidus remains heavily debated. This systematic review of the current literature suggests that interposition arthroplasty is a viable short and intermediate term treatment for hallux rigidus in terms of patient satisfaction, pain scores, and AOFAS scores. Further studies with greater sample sizes, more uniform methods, and longer follow-up times are needed to further support the superiority of interposition arthroplasty