Surgical correction of coxa vara: Evaluation of neck shaft angle, Hilgenreiner-epiphyseal angle for indication of recurrence

Abstract

Background: Coxa vara is a hip deformity in which the femoral neck-shaft angle decreases below its normal value. Standard surgical treatment for this condition is corrective valgus osteotomy. Appropriate correction of the Hilgenreiner-epiphyseal angle is important to prevent recurrence. The purpose of this study is to: 1) evaluate the recurrence of the deformity at the latest follow up; and 2) find the appropriate angle of correction associated with the lowest recurrence. Methods: 34 hips in 31 patients who underwent surgery for treatment of coxa vara from 2005 to 2014 were included. Patient-reported outcomes, Hilgenreiner-epiphyseal angle, and neck-shaft angle were assessed preoperatively, postoperatively, and at latest follow-up. Results: The mean age at surgery was 10.99, with a range of 5-30, years. Preoperative neck-shaft angle ranged from 60 to 100 degrees, and Hilgenreiner-epiphyseal angle ranged from 60 to 90 degrees. At the latest follow up, the neck-shaft angle ranged from 120 to 135 degrees and the Hilgenreiner-epiphyseal angle ranged from 22 to 35 degrees (p < 0.001). The Harris hip score improved from 47.20 (34-66) to 79.68 (60-100) (p < 0.001). There was no recurrence of deformities at the mean follow up of 37.87 months. Conclusion: Surgical correction of coxa vara in various pathologies can be done successfully with the Hilgenreiner-epiphyseal angle corrected to 35 degrees or the neck shaft angle corrected to > 120 degrees in order to prevent recurrence of the deformity. Majority of the patients were reported improvement of hip function. However, a longer-term follow up is required to determine further outcomes regarding to recurrence of the deformity.

The neck–shaft angle: an update on reference values and associated factors

“…The neck-shaft angle is frequently used for diagnostics, preoperative planning, and therapy (Srisaarn et al 2019), but no consensus on thresholds or reference ranges exists to date. In addition, various associations with sex and age are described, while other possible associations have rarely been investigated.…”

“…The femoral neck-shaft angle (NSA) or centrum-collumdiaphyseal angle has long served as an important measure to quantify the inclination between the femoral neck and the femoral shaft. Due to its importance in diagnostics for many pathologies of the proximal femur and resultant therapy, e.g., corrective osteotomy (Srisaarn et al 2019), the NSA is still frequently used by surgeons. However, the currently published reference ranges were mostly based on anatomic specimens, small cohorts (Boese et al 2016), or originated from hospitalbased studies.…”

Cirugía en coxa vara por osteogénesis imperfecta. Reporte de dos casos

“…In a study published in 2019, Srisaarn et al 13 evaluated 31 patients (34 hips) aged 5 to 30 years who underwent coxa vara correction surgery between 2005 and 2014. In adolescent patients, they used the technique described by Finidori and placed plate and nail, while in adults, they used gamma nail plus dynamic compression plates or angle blade plate.…”

Mesenchymal stem cells in the treatment of osteogenesis imperfecta

“…The mutated form of CRTAP leads to moderate symptoms, while the absence of CRTAP results in lethality (Etich et al 2020 ). Clinical manifestations of the mutated form include fractures at birth, bluish sclerae, coxa vara, and a short humerus, femur, and stature (Etich et al 2020 ; Ward et al 2002 ; Srisaarn et al 2019 ; Roberts et al 2018 ). Type VIII is caused by a mutation in the LEPRE1 gene resulting in a deficiency of prolyl 3-hydroxylase 1 (P3H1) (Otsuru et al 2012 ; Morello and Rauch 2010 ).…”