Variability in the assessment of fracture-healing in orthopaedic trauma studies

Background: There is a lack of consensus among orthopaedic surgeons in the assessment of fracture-healing. We conducted a systematic review of recent clinical studies of long-bone fracture care that were published in three major orthopaedic journals to identify current definitions of fracture-healing. Methods: MEDLINE and the computerized databases for The Journal of Bone and Joint Surgery (American Volume), The Journal of Bone and Joint Surgery (British Volume), and the Journal of Orthopaedic Trauma were searched from January 1996 through December 2006 with use of title, abstract, keyword, and medical subject headings. Therapeutic clinical studies of long-bone fractures of the appendicular skeleton in adults in which fracture-healing was assessed were selected. Two reviewers independently identified articles and extracted data. Any disagreement was resolved by consensus. We qualitatively and quantitatively summarized the definition of fracture union and the reliability of the assessment of radiographic fracture-healing. Results: One hundred and twenty-three studies proved to be eligible. Union was defined on the basis of a combination of clinical and radiographic criteria in 62% of the studies, on the basis of radiographic criteria only in 37%, and on the basis of clinical criteria only in 1%. Twelve different criteria were used to define fracture union clinically, and the most common criterion was the absence of pain or tenderness at the fracture site during weight-bearing. In studies involving the use of plain radiographs, eleven different criteria were used to define fracture union, and the most common criterion was bridging of the fracture site. A quantitative measure of the reliability of the radiographic assessment of fracture union was reported in two studies. Conclusions: We found a lack of consensus with regard to the definition of fracture-healing in the current orthopaedic literature. Without valid and reliable clinical or radiographic measures of union, the interpretation of fracture care studies remains difficult.