Joint-Sparing Reconstructive Procedures vs Hindfoot Fusion in the Treatment of Progressive Collapsing Foot Deformity. A Retrospective-Comparative Analysis

Research Type: Level 3 - Retrospective cohort study, Case-control study, Meta-analysis of Level 3 studies Introduction/Purpose: The study aimed to compare the clinical and radiographic outcomes of surgical treatments for Flexible (Stage 1) and Rigid (Stage 2) Progressive Collapsing Foot Deformity (PCFD), specifically joint-preserving reconstructive procedures and hindfoot fusions. Despite the common use of these procedures, there is a lack of comprehensive evidence comparing their outcomes under a standardized protocol and follow-up. This retrospective cohort study, conducted by a single surgeon at a single institution, sought to address this gap by evaluating and comparing the results of patients who underwent either joint-sparing hindfoot procedures for flexible (stage 1) PCFD or hindfoot fusions for rigid (stage 2) PCFD. The hypothesis was that while hindfoot fusions would achieve better radiographic correction, joint-preserving reconstructive surgery would result in superior clinical outcomes. Methods: In this IRB-approved retrospective comparative cohort study, we included 54 adult PCFD patients (33 female, 21 male, mean age 54.2 years, mean BMI 32.2 kg/m2) who underwent operative treatment by a single surgeon at a single institution. Thirty-six flexible (Stage 1) PCFD patients underwent joint-sparing procedures, while 18 rigid PCFD patients (Stage 2) underwent hindfoot fusions. The minimum follow-up was six months (average 11.2 months). Preoperative and three-month postoperative Weightbearing CT (WBCT) scans were utilized to assess alignment using a combination of PCFD semiautomated and manual measurements. Complications were documented, and clinical outcomes were evaluated through PROMIS Physical Function (PF) and Pain Interference (PI) scores at baseline, three-, and six-months post-surgery. Comparison between flexible and rigid PCFD was conducted using T-tests or Wilcoxon tests. Additionally, multivariate and linear regression analyses were employed to identify radiographic predictors of PROMIS at six months, with significance set at P < .05. Results: Groups were similar for gender/BMI, but reconstruction patients were younger (48.9 vs. 64.7 yeas, p=0.001). Complications were similar in both groups. PROMIS-PF/PI were similar preoperatively (PF 38.4, PI 64.1). At 3 months, PROMIS-PF was similar between groups (32.9), but PROMIS-PI was significantly lower in fusion group (55.8 vs. 61.4). At 6-months, both PROMIS-PF (40.4 vs. 38.4, p=0.03) and PROMIS-PI (64.1 vs.56.5, p< 0.0001) significantly improved compared to pre-operatively and were similar between groups. Additionally, all WBCT radiographic parameters improved significantly postoperatively for both groups (all p-values < 0.05), but fusion lead to more pronounced correction of abduction and arch collapse deformities. Multivariate regression analysis revealed that postoperative alignment/sinus tarsi impingement/age significantly influenced PROMIS-PF (p=0.0002, R2 0.84), while sinus tarsi impingement/BMI/gender significantly influenced PROMIS-PI (p < 0.0001, R2 0.82). Conclusion: This study compared the effectiveness and outcomes of joint-sparing hindfoot procedures and hindfoot fusions in treating PCFD. Both treatments showed significant improvements in radiographic PCFD parameters and patient-reported outcomes post-surgery. Hindfoot fusions were found to provide greater correction of abduction and longitudinal arch collapse compared to reconstruction. However, there were no significant differences in the correction of hindfoot valgus deformity or in patient-reported outcomes after 6 months, as PROMIS physical function and pain interference scores were similar in both groups. Further prospective and longer-term studies comparing reconstructive and hindfoot fusion surgical treatments for PCFD are warranted.