Bone remodelling after scaphoid fractures: HR-pQCT, clinical and laboratory data from a prospective 1-year follow-up study.

Abstract

Introduction: The exact mechanisms of bone remodelling after scaphoid fractures are not fully understood. Blood supply may lead to delayed consolidation and non-unions as challenging long-term problems. The aim of this study was to follow-up the microstructure during the scaphoid bone remodelling process using High Resolution peripheral Quantitative Computed Tomography (HR-pQCT) and compare the results with clinical and laboratory data.

Patients and methods: In this monocentric, prospective, controlled, clinical trial 39 patients with an unilateral conservatively treated scaphoid fracture at the level of the waist or the distal pole were followed up over one year (2, 4, 6, 12, 26 and 52 weeks after trauma). Fracture healing was monitored by clinical examination, blood bone remodelling markers and HR-pQCT.

Results: The HR-pQCT showed significant changes in trabecular number, trabecular thickness, trabecular separation and bone mineral density until the 52 week follow-up. Complete bony consolidation on HR-pQCT was evident in half of the fractures at 12 weeks and in all fractures at 52 weeks after trauma. None of the patients developed a non-union. Carboxy-terminal collagen crosslinks as resorption marker showed significant changes until the 52 week follow-up.

Conclusion: This study shows detailed clinical, laboratory and radiologic changes during follow-up of uncomplicated fracture healing of conservative scaphoids. Bony consolidation is highly variable and can take up to one year after fracture. Larger studies are warranted, as HR-pQCT might provide detailed microstructural information to better predict fracture healing processes, thus acting as a high-resolution and low-radiation alternative to standard conventional CT.