Subtalar arthroereisis improved clinical and radiographic outcomes in pediatric and adolescent patients with flexible flatfoot regardless of implant material, although bioabsorbable devices were associated with fewer implant-related symptoms and fewer nonroutine removals, according to a systematic review and meta-analysis published in The Foot.
The findings were based on limited comparative evidence, with only two nonrandomized cohort studies directly comparing implant types, and the overall certainty of evidence was rated low to moderate using the GRADE framework.
The analysis included 39 studies totaling over 2,000 feet. Researchers searched PubMed, Embase, Cochrane Library, and Web of Science through December 2024 and included randomized trials, prospective cohort studies, and retrospective series evaluating subtalar arthroereisis in patients younger than 18 years.
Across pooled single-arm data, persistent sinus tarsi pain occurred in about 8% of metallic implant cases and 6% of bioabsorbable cases. Nonroutine implant removal or revision occurred in about 8% and 5% of cases, respectively. In the comparative analysis, metallic implants were associated with 1.8 times the odds of persistent sinus tarsi pain and showed a trend toward 2.2 times the odds of nonroutine implant removal compared with bioabsorbable devices.
Radiographic outcomes, including Meary’s angle and calcaneal pitch, improved substantially from preoperative to postoperative assessments in both groups, with most patients achieving near-normal alignment. However, the review found no consistent evidence that either implant type provided superior radiographic correction.
Patient-reported outcomes, including functional scores and pain measures, also improved across implant types. However, reporting was imbalanced across cohorts: widely used functional measures such as the American Orthopaedic Foot & Ankle Society score were reported in multiple metallic cohorts but were sparse or absent in bioabsorbable cohorts, whereas other measures such as the Foot Function Index and visual analog scale pain scores were reported in smaller bioabsorbable samples and showed similar improvements.
Most included studies were retrospective and demonstrated a moderate risk of bias, and follow-up was typically limited to 2 to 3 years. Differences in implant design, surgical technique, and use of concomitant procedures contributed to heterogeneity across studies.
“Bioabsorbable devices may reduce the risk of persistent sinus tarsi pain and non-routine implant removal compared with metallic implants, although these advantages are modest and supported by only two comparative studies,” wrote study researcher Daniela Alessia Marletta, of the University of Messina, and colleagues.
The researchers concluded that implant selection should be individualized based on patient age, deformity severity, and surgeon experience, given the limited certainty of comparative evidence.
The researchers reported no competing interests.
Source: The Foot