Effect of Vitamin D Supplementation Regimens on Fracture Healing and Serum Biomarker Profile in Long-Bone Fractures:...

Vitamin D plays a critical role in bone metabolism and mineralization, and deficiency is highly prevalent among patients presenting with long-bone fractures. Impaired Vitamin D status may adversely affect fracture healing by disrupting calcium homeostasis and bone remodeling. However, the optimal supplementation regimen for improving fracture healing outcomes remains uncertain. To compare the effects of daily low-dose versus weekly high-dose Vitamin D supplementation on fracture healing and serum biomarker profiles in patients with long-bone fractures.

This prospective randomized study included 50 adult patients with acute long-bone fractures and baseline serum 25-hydroxyvitamin D levels below 30 ng/mL. Patients were randomized into two groups: Group A received oral Vitamin D3 1,000 IU daily, while Group B received oral Vitamin D3 60,000 IU weekly, both for 12 weeks. Serum Vitamin D, calcium, phosphorus, alkaline phosphatase, and parathyroid hormone (PTH) levels were assessed at baseline, 12 weeks, and 24 weeks. Fracture healing was evaluated clinically and radiologically, with time to union recorded. Statistical analysis was performed using appropriate parametric and non-parametric tests, with P < 0.05 considered significant.

Both supplementation regimens significantly improved serum Vitamin D levels; however, the weekly regimen achieved higher levels at 12 weeks (32.8 ± 7.4 ng/mL vs. 27.3 ± 6.1 ng/mL; P = 0.01) and 24 weeks (36.2 ± 7.9 ng/mL vs. 30.5 ± 6.8 ng/mL; P = 0.004). Serum calcium levels increased and PTH levels decreased significantly, with greater changes observed in the weekly supplementation group. The mean time to radiological fracture union was significantly shorter in Group B (15.9 ± 2.8 weeks) compared to Group A (18.6 ± 3.2 weeks; P = 0.002). Both regimens were well tolerated, with no serious adverse events.

Weekly high-dose Vitamin D supplementation resulted in superior biochemical correction and faster fracture healing compared to daily low-dose supplementation in Vitamin D-deficient patients with long-bone fractures. Routine assessment and targeted correction of Vitamin D deficiency may improve fracture healing outcomes.