Comparison of vitamin D, parathyroid hormone (PTH), and bone metabolism markers in hip fracture patients by fracture type and control group.

BACKGROUND

Vitamin D, calcium, and bone metabolism markers play a critical role in skeletal health; however, their relationship with different hip fracture types remains uncertain. This study aimed to investigate serum levels of 25(OH) vitamin D, calcium, parathyroid hormone (PTH), alkaline phosphatase (ALP), phosphorus, total protein, and albumin in elderly patients with femoral neck fractures (FNF) and intertrochanteric femur fractures (ITFF), compared to a control group.

METHODS

This retrospective study included 375 patients aged 65 years and older, comprising 117 patients with ITFF, 97 with FNF, and 161 control cases (coxarthrosis/gonarthrosis). Serum biochemical parameters were analyzed using standard laboratory methods. Fractures were classified according to the AO/OTA (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association) system by two independent observers, and interobserver agreement was assessed using Cohen's kappa coefficient (κ=0.89). Group comparisons were performed using one-way analysis of variance (ANOVA) followed by post hoc Bonferroni tests. A p value <0.05 was considered statistically significant.

RESULTS

Vitamin D levels were significantly lower in both the ITFF and FNF groups compared to controls (p<0.01), while no significant difference was observed between the ITFF and FNF groups (p>0.05). Similarly, calcium, total protein, and albumin levels were lower in fracture groups than in controls (p<0.01). In contrast, PTH levels were significantly higher in patients with fractures (p=0.001).

CONCLUSION

Deficiencies in vitamin D and calcium were associated with an increased risk of hip fractures but did not appear to influence fracture pattern. These findings suggest that systemic biochemical parameters should be emphasized in comprehensive fracture risk assessment, underscoring the importance of preoperative evaluation and postoperative correction of metabolic deficiencies in patients with hip fractures.