Is interposition arthroplasty a viable option for treatment of moderate to severe hallux rigidus? - A systematic review and meta-analysis.

INTRODUCTION: When conservative therapy for hallux rigidus fails, surgical options such as arthrodesis and interposition arthroplasty can be considered. Although arthrodesis of MTP joint is the gold standard treatment. However patients desiring MTP joint movement may opt for either interposition arthroplasty or implant arthroplasty to avoid the movement restrictions of arthrodesis. The purpose of this systematic review was to investigate clinical outcomes and complications following interposition arthroplasty for moderate to severe hallux rigidus, for patietns who would prefer to maintain range of motion in the MTP joint. METHODS: A systematic search on MEDLINE, EMBASE and Cochrane library database was performed during February 2018. Demographics, surgical techniques, clinical outcomes, radiological outcomes and complications were recorded from each included study. Pooled statistics performed for variables with homogenous data across the studies. A linear regression model used to compare the clinical outcomes between autogenous vs allogenous material interposition arthroplasty. RESULTS: Fifteen articles were included in the systematic review. Mean AOFAS scores improved from preoperative 41.35 to postoperative 83.17. Mean pain, function, and alignment score 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° (5-30) to 42.03° (25-71). Mean ROM improved from 21.06° to 46.43°. Joint space increased from 0.8mm to 2.5mm. The most common postoperative 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: Interposition arthroplasty is an effective treatment option with acceptable clinical outcomes in patients with moderate-severe hallux rigidus who prefer to maintain range of motion and accept the risk of future complications. LEVEL OF EVIDENCE: IV.

Mid-term outcomes of first metatarsophalangeal arthroplasty using the Primus FGT double-stemmed silicone implants.

BACKGROUND: Silicone implants for first metatarsophalangeal (MTP-1) arthroplasty are regaining popularity, though most studies have long inclusion periods, or short follow-up. The authors aimed to report mid-term outcomes of a cohort that received a third-generation MTP-1 implant at minimum follow-up of 5 years. METHODS: The authors evaluated 70 MTP-1 arthroplasties performed in 64 patients using the Primus™ Flexible Great Toe implant. The indications were hallux rigidus of grade II (10%) and grade III (87.1%) or revision surgery (2.9%). RESULTS: All patients completed clinical and radiographic assessments at 83.5 months (range, 62-114). There were no revisions or reoperations and the AOFAS-HMI score was 88.9±9.1 (median, 90; range, 67-100). Metatarsalgia was 'absent' in 47.1%, 'mild' in 41.1%, 'moderate' in 7.1% and 'severe' in 1.4%. CONCLUSION: This study reported excellent mid-term clinical outcomes and survival rates of a third generation MTP-1 arthroplasty design and confirmed findings of recent studies regarding efficacy of silicone double-stemmed implants. LEVEL OF EVIDENCE: Level IV case series.

Clinical, Radiographic, and Patient-Reported Outcomes of First Metatarsophalangeal Interposition Arthrodesis Using Porous Titanium Wedges.

BACKGROUND: First metatarsophalangeal (MTP) arthrodesis is a common surgical procedure for addressing hallux MTP pathology. In the setting of revision procedures with significant bone loss, porous titanium wedges may provide an alternative to structural bone autograft or allograft. OBJECTIVE: The purpose of this study is to report the clinical and radiographic outcomes achieved in first MTP interposition arthrodesis using porous titanium wedges. METHODS: A retrospective analysis of 9 patients with a mean age 65.4 years (45-82 years) who underwent first MTP interposition arthrodesis with the use of porous titanium wedges from February 2014 to September 2017 was performed. Outcomes were assessed using both plain-film radiographs and computed tomography (CT) scans, as well as patient-reported outcome measures, including Foot and Ankle Ability Measure (FAAM) (Sports and Activities of Daily Living), pain Visual Analogue Scale (VAS), and 36-Item Short Form Survey (SF-36). Average follow-up time was 34.2 months (14-72 months). RESULTS: At final follow-up, the average FAAM score was 91.1 ± 14.7 (75.1 ± 5.3 FAAM Activities of Daily Living; 17.9 ± 9.9 FAAM Sports). Average pain VAS score was 1.9 ± 1.7. Postoperative computed tomography (CT) imaging was obtained for 5 patients, all of which demonstrated good bony apposition or osseous integration of the wedge. Four patients underwent subsequent surgical procedures, including 3 isolated dorsal fixation revisions, and 1 complete MTP arthrodesis revision. CONCLUSION: To our knowledge, this study represents the first reported clinical and radiographic outcomes in patients undergoing first MTP interposition arthrodesis with use of porous titanium wedges. While we found this technique to be a viable alternative to bone grafting for this difficult problem, further research should focus on comparative data with other commonly performed operative techniques. LEVEL OF EVIDENCE: Level IV: Case series.

Preoperative Risk Factors for Primary Metatarsophalangeal Arthroplasty Revision to MTP Arthrodesis for Hallux Rigidus.

BACKGROUND: Revision or conversion to arthrodesis following metatarsophalangeal (MTP) joint arthroplasty are salvage procedures to manage complications of MTP joint arthroplasty. The purpose of this study is to use a national administrative database to characterize nationwide trends of patients undergoing hallux MTP arthrodesis vs arthroplasty for hallux rigidus. Additionally, the authors sought to evaluate demographic trends and evaluate influence of patient-related risk factors in those undergoing MTP arthroplasty revision to arthrodesis. METHODS: Patients who underwent MTP arthroplasty for diagnosis of hallux rigidus from 2010 to 2019 were identified in the Mariner subset of the PearlDiver database. Patients were included if they had undergone MTP arthroplasty for the diagnosis of hallux rigidus. Notably, the database lacks resolution about critical features of the arthroplasty design and materials. The revision cohort encompassed patients who underwent subsequent ipsilateral MTP arthrodesis or arthroplasty within 2 years of index arthroplasty procedure. Demographic characteristics and medical comorbidities were examined as potential patient-related risk factors for arthroplasty revision or revision to fusion. Univariate analyses were performed to analyze differences in patient demographics, comorbidities, and risk factors. A multivariate regression analysis was subsequently conducted to control for confounding variables. RESULTS: 2750 patients underwent primary MTP arthroplasty for diagnosis of hallux rigidus. Of these, 44 (1.6%) underwent revision arthroplasty and 188 patients (6.8%) were revised to arthrodesis within the first 2 years after the index procedure. Multivariate regression analysis indicates that obesity (odds ratio [OR] 1.48, 95% CI 1.05-2.09), depression (OR 1.59, 95% CI 1.15-2.20), and steroid use (OR 2.94, 95% CI 1.30-6.65) were associated with a statistically significant increase in revision to arthrodesis from primary arthroplasty. CONCLUSION: Revision arthrodesis following primary MTP arthroplasty for hallux rigidus within 2 years was found to be a relatively common occurrence in this national insurance database study. Risk factors for revision arthroplasty to arthrodesis within 2 years of primary arthroplasty include obesity, depression, and steroid use. LEVEL OF EVIDENCE: Level III, case-control study.