Different kinetics of bone markers in normal and delayed fracture healing of long bones.

Abstract

No clinical tests can predict delayed fracture healing. Early knowledge about the individual prognosis of a fracture could help to prevent severe complications (e.g., pseudoarthrosis), and enable the physician to modify therapy. Plain radiography remains the standard method to monitor fracture healing, but it documents delayed healing only late in the course. Biochemical bone markers might provide earlier information. Osteocalcin (OC) and bone alkaline phosphatase (ALP), both markers of bone formation, as well as serum type I collagen C-terminal telopeptide (β-CTx), a marker of bone degradation, are used mainly to monitor bone-consuming diseases and antiresorptive therapies (1)(2)(3)(4)(5)(6)(7)(8)(9). Few studies have analyzed the behavior of these markers after fracture. We evaluated their ability to distinguish patients with normal and delayed fracture healing before radiologic evidence of delay is available. We investigated 14 patients with a traumatic crural (n = 13) or femoral (n = 1) shaft fracture (Table 1⇓ ). All patients underwent operative therapy and were monitored for 1 year. No patient suffered from diseases or had been administered medication known to interfere with bone metabolism. Blood samples for measurement of OC, bone ALP, and β-CTx were taken within 24 h of fracture and after 7, 14, 28, 42, 60, 90, 180, and 365 days. Serum was separated from whole blood and stored at −20 °C until measurement. We also evaluated a clinical score of fracture healing. At the end of the study, patients were classified as having normal or delayed fracture healing. The rate of healing was considered normal if the fracture healed completely after 6 months (score 4) and score 2 was reached on day 60. Otherwise, fracture healing was classified as delayed. The clinical score was defined as follows: (0), …