To assess new-onset flatfoot after ACL reconstruction using peroneus longus tendon autografts and examine associated factors.
Approach:
Design and participants: Prospective observational study of 130 patients aged 16 years or older who underwent primary single-bundle ACL reconstruction by one surgeon and had at least 12 months of follow-up.
Assessment: Foot posture was assessed at scheduled postoperative visits using digital footprints and several indices; flatfoot incidence was primarily defined as an Arch Index greater than 0.26.
Key Findings:
Two of 130 patients (1.5%) met the primary Arch Index definition of flatfoot; both cases were on the operated side, and none were identified in the contralateral foot.
Both patients with flatfoot were asymptomatic, with no reported pain, instability, or limitations in daily or sports activities.
Classification varied by measure: the Chippaux-Smirak Index identified 2 patients (1.5%), the Staheli Index 24 (18%), and the Clarke angle 61 (47%).
No statistically significant associations were reported with Beighton score, BMI, weight, or height. The two patients with flatfoot were older than those without it (46 vs. 26 years), but the authors cautioned against generalizing this finding.
Interpretation:
The authors reported a 1.5% incidence of flatfoot using the primary Arch Index definition and characterized the risk of clinically significant postoperative flatfoot as minimal. Foot posture classifications differed substantially across measurement methods.
Limitations:
Only two patients met the primary flatfoot outcome, preventing multivariable analysis and limiting conclusions about risk factors.
Assessments used static digital footprints; dynamic gait biomechanics and radiographic or 3-dimensional imaging were not evaluated.
The study was conducted at one center by one surgeon, and approximately 91% of participants were male.
There was no comparison group receiving alternative grafts.
Conclusion:
The study authors reported that ACL reconstruction using a peroneus longus autograft carried a minimal risk of clinically significant postoperative flatfoot, based on the Arch Index.
Patients with preoperative vitamin D deficiency had higher postoperative pain scores and opioid use after mastectomy, including more than triple the odds of moderate to severe pain within 24 hours of surgery.
