Introduction: Bone turnover markers (BTMs) can be used to monitor bone metabolism, while the actual clinical changing in hip fracture had not been certified to evaluate the changes of BTMs during the healing process after surgery of elderly hip fractures; and to get the effects of operation type, gender, serum 25(OH)D level, and age on bone turnover markers.
Materials and methods: A total of 100 elderly cases with hip fracture were selected, including 74 females and 26 males, and the patients were followed to 180-230 days after surgery. Serum levels of N-propeptide of type 1 collagen (P1NP), C-terminal crosslinking telopeptides of type 1 collagen (CTX), Osteocalcin (OC), and 25 hydroxy vitamin D (25OHD) were investigated. Bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry (DXA).
Results: (1) P1NP and CTX showed peak time at 30-60 days after operation, while OC keep going even at 180-230 days; P1NP showed less than 4 times elevation during healing, CTX and OC only had less than 2 times rise. (2) Female had higher serum CTX and OC than male, intramedullary nailing for intertrochanteric fracture patients had higher P1NP than hip replacement for femoral neck fracture patients, and both the degrees of increase were less than 50%. (3) Serum average 25(OH)D level had no effect on BTMs during the fracture healing; different from the young old (65-84 years), serum OC level of eldest older patients(≥ 85 years) decreased early in the process of fracture healing.
Conclusions: BTMs reached the peak level in 30-60 days after surgery, P1NP showed less than 4 times elevation, and CTX and OC had less than 2 times rise. It was not necessary to take gender into account when observing P1NP, and it was not necessary to take fracture and operation type into account when observing CTX and OC.
Keywords: Bone turnover markers; Fracture healing; Hip fracture; Osteoporosis.