Kramer and Chevron Osteotomy for Hallux Valgus Deformity - Retrospective Comparison of Functional and Radiological Results

BACKGROUND: Hallux valgus is the most common forefoot deformity, with a prevalence of up to 23%. Surgical treatment is necessary in symptomatic patients. Prospective studies comparing different procedures are rare. Chevron osteotomy is the preferred procedure for distal osteotomy. The relevance of Kramer osteotomy is not clearly defined. The objective of this study was to compare the two procedures in terms of functional and radiological outcome.

MATERIAL AND METHODS: 174 patients (42 male, 132 female, 44.0 ± 16.8 years), treated with Chevron (n = 71) or Kramer osteotomy (n = 103) between 2008 and 2015, were enrolled in this retrospective study. Time for surgery was analysed. Pre- and postoperative X-rays were evaluated to detect hallux valgus angle, intermetatarsal angle and position of sesamoids (mean ± SD). Function and quality of life were assessed using the Foot and Ankle Outcome Score (FAOS) and EuroQol5D questionnaire. Pain was rated by using the numeric rating scale (NRS). Statistical analyses were performed with mixed model ANOVA and the t test for independent samples.

RESULTS: Both procedures reduce the hallux valgus angle (Kramer: 30° to 9°; Chevron 26° to 16°; p < 0.001). A significant difference was found between the two procedures (10° ± 2°; 95% CI: - 12.93; - 6.49; p < 0.001). A minimally reduced intermetatarsal angle was found in both groups (14° ± 3° to 12° ± 3°; p < 0.001). However, there was no significant difference between the two procedures (p = 0.116). The position of sesamoids was more improved by Kramer osteotomy (2/2 to 0/1; p < 0.001) according to Appel than with the Chevron osteotomy (2/2 to 2/1; p = 0.052). Time for surgery was significantly shorter when Kramer osteotomy was performed (31 ± 14 min vs. 44 ± 12 min; p < 0.001). No relevant differences in pain and function were observed (NRS postoperative Chevron: 1.3; Kramer: 1.7; p = 0.413; FAOS: no significant differences in all categories).

CONCLUSION: The results of the two procedures were equal in functional outcome. Time of surgery and radiological results were significantly better in the group with Kramer osteotomy. Therefore, Kramer osteotomy is an alternative option to Chevron osteotomy. Further prospective studies are necessary to confirm these results.