Influence of sesamoid position after scarf osteotomy for hallux valgus on patient-reported outcome. A prospective cohor study

Abstract

Background: The objective was to evaluate the influence of the postoperative sesamoid position as measured with conventional radiographs on the patient-reported outcome after scarf osteotomy. The hypothesis was that incomplete reduction of the sesamoid would result in a decreased functional outcome.

Methods: Eighty-two patients who underwent scarf osteotomy for hallux valgus were prospectively assessed for up to two postoperative years. The Self-Reported Foot and Ankle Score (SEFAS) was used to assess the quality of life, and the American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale (AOFAS) for the functional outcome. A visual analogue scale (VAS) assessed pain, and Likert scale for patient satisfaction. Radiologically, hallux valgus angle (HVA), first-second intermetatarsal angle (IMA), and sesamoid position were analyzed. According to the final sesamoid position, patients were classified as normal position (48 patients) and outlier position (34 patients). A power analysis, conventional and logistic regression statistical analysis were performed.

Results: At the final follow-up, significant improvements in all clinical scores were observed for both groups (p = 0.001) with no significant difference in AOFAS score (p = 0.413), but SEFAS score (p = 0.023), VAS-pain (p = 0.006), and satisfaction (p = 0.014) were significantly better in the normal group than in the outlier group. There were significant differences between groups in final HVA (p = 0.042) and IMA (p = 0.040). In multivariate analysis, only lower VAS-pain score (OR 0.4, 95% CI 0.2-0.6; p = 0.039) and normal sesamoid position (OR 2.4, 95% CI 1.6-3.2; p = 0.012) were significant predictor of patient satisfaction.

Conclusion: At two postoperative years, normal sesamoid position as measured on weight-bearing radiographs was associated with lower pain and better patient satisfaction in patients underwent scarf osteotomy for moderate to severe hallux valgus.

Keywords: Hallux valgus; Patient-reported outcome; Satisfaction; Scarf osteotomy; Sesamoid position.