Subtalar Arthroereisis as a Surgical Option in the Reconstruction of Progressive Collapsing Foot Deformity: A Prospective 3-year Follow-up Study on Patient Satisfaction and Causes for Implant Removal in 40 Cases Treated with the HyProCure Implant

Background and purpose: Subtalar arthroereisis in the surgical treatment of Progressive Collapsing Foot Deformity is associated with high implant removal rates. This study reports the mid-term incidence and causes for implant removal, patient-reported outcomes, and radiographical results. Patients and methods: Prospectively collected data from 40 cases in 37 patients were analyzed. Subtalar arthroereisis was performed with a HyProCure-I implant as a single procedure in 19 cases and as an adjuvant procedure in 21 cases. In all cases, a Self-reported Foot and Ankle Score (SEFAS) was completed preoperatively. At the final follow-up, SEFAS was available in 32 cases. Standard weightbearing lateral and anteroposterior (AP) radiographs were obtained preoperatively in all cases and at final follow-up in 29 cases. Results: The implant was removed in four single procedure cases and four combined procedure cases (20%). Causes for pain leading to implant removal are discussed. Patient satisfaction in the remaining 32 cases was similar in both groups. Mean SEFAS improvement was 14.5 points [95% confidence interval (CI), 10.6–18.5] in the single procedure group and 17.2 points (95% CI, 12.0–22.3) in the combined procedure group. Similar radiographical improvements were noted in the two groups. Interpretation: Subtalar arthroereisis with a HyProCure-I implant, performed as either a single or a combined procedure, may yield good subjective results and radiographical improvement with high patient satisfaction rates. The 20% mid-term implant removal rate is still relatively high, and careful patient selection is needed for either procedure.