Evaluation of Serum Calcium, Phosphorus, and Alkaline Phosphatase Levels in Patients with Fracture Healing: A Prospective Study

Abstract

Fracture healing is a complex biological process involving inflammation, repair, and remodeling phases. Biochemical markers such as serum calcium, phosphorus, and alkaline phosphatase (ALP) may reflect osteoblastic activity and mineralization during bone repair.

Objectives

1. To assess changes in serum calcium, phosphorus, and ALP levels during fracture healing.
2. To determine the association of these biochemical markers with the rate of fracture union.

Methods

This prospective observational study included adult patients with long-bone fractures managed either conservatively or surgically. Serum calcium, phosphorus, and ALP levels were measured at baseline, 6 weeks, and 12 weeks. Fracture union was assessed radiologically and clinically at follow-up visits. Patients were categorized into normal union and delayed union groups.

Results

A total of 120 patients completed follow-up. Mean ALP levels showed a significant rise at 6 weeks compared with baseline (p<0.001) and gradually declined by 12 weeks. Serum calcium and phosphorus demonstrated modest but significant changes during healing (p<0.05). Patients with delayed union had lower ALP elevation at 6 weeks and persistently lower phosphorus levels compared with patients achieving normal union (p<0.05).

Conclusion

Serum ALP appears to be a useful biochemical marker of fracture healing, while serum calcium and phosphorus provide supportive information regarding mineral metabolism. Early changes in ALP may help identify patients at risk of delayed fracture union.

Keywords: Fracture healing, Alkaline phosphatase, Calcium, Phosphorus, Delayed union, Bone biomarkers.