Assessment of the healing process in distal radius fractures by high resolution peripheral quantitative computed tomography.
In clinical practice, fracture healing is evaluated by clinical judgment in combination with conventional radiography. Due to limited resolution, radiographs don't provide detailed information regarding the bone micro-architecture and bone strength. Recently, assessment of in vivo bone density, architectural and mechanical properties at the microscale became possible using high resolution peripheral quantitative computed tomography (HR-pQCT) in combination with micro finite element analysis (μFEA). So far, such techniques have been used mainly to study intact bone. The aim of this study was to explore whether these techniques can also be used to assess changes in bone density, micro-architecture and bone stiffness during fracture healing. Therefore, the fracture region in eighteen women, aged 50 years or older with a stable distal radius fracture, was scanned using HR-pQCT at 1-2 (baseline), 3-4, 6-8 and 12weeks post-fracture. At 1-2 and 12 weeks post-fracture the distal radius at the contra-lateral side was also scanned as control. Standard bone density, micro-architectural and geometric parameters were calculated and bone stiffness in compression, torsion and bending was assessed using μFEA. A linear mixed effect model with time post-fracture as fixed effect was used to detect significant (p-value ≤0.05) changes from baseline. Wrist pain and function were scored using the patient-rated wrist evaluation (PRWE) questionnaire. Correlations between the bone parameters and the PRWE score were calculated by Spearman's correlation coefficient. At the fracture site, total and trabecular bone density increased by 11% and 20%, respectively, at 6-8 weeks, whereas cortical density was decreased by 4%. Trabecular thickness increased by 23-31% at 6-8 and 12 weeks and the intertrabecular area became blurred, indicating intertrabecular bone formation. Compared to baseline, calculated bone stiffness in compression, torsion and bending was increased by 31% after 12 weeks. A moderate negative correlation was found between the stiffness and the PRWE score. No changes were observed at the contra-lateral side. The results demonstrate that it is feasible to assess clinically relevant and significant longitudinal changes in bone density, micro-architecture and mechanical properties at the fracture region during the healing process of stable distal radius fractures using HR-pQCT.
Research School NUTRIM, Maastricht University, The Netherlands; Department of Rheumatology, Maastricht University Medical Center, The Netherlands. Electronic address: joost.dejong@maastrichtuniversity.nl.
Joost J A
JJ
de Jong
Department of Orthopedics, Maastricht University Medical Center, The Netherlands; Research school CAPHRI, Maastricht University, The Netherlands.
Paul C
PC
Willems
Department of Orthopedics, Maastricht University Medical Center, The Netherlands; Research school CAPHRI, Maastricht University, The Netherlands.
Jacobus J
JJ
Arts
Department of Rheumatology, Maastricht University Medical Center, The Netherlands.
Sandrine G P
SG
Bours
Department of Surgery, Maastricht University Medical Center, The Netherlands.
Peter R G
PR
Brink
Research school CAPHRI, Maastricht University, The Netherlands; Department of General Practice, Maastricht University, The Netherlands.
Tineke A C M
TA
van Geel
Research School NUTRIM, Maastricht University, The Netherlands; Department of Surgery, Maastricht University Medical Center, The Netherlands.
Martijn
M
Poeze
Department of Rheumatology, Maastricht University Medical Center, The Netherlands; Research school CAPHRI, Maastricht University, The Netherlands; Faculty of Medicine and Life Sciences, Hasselt University, Belgium.
Piet P
PP
Geusens
Faculty of Biomedical Engineering, Eindhoven University of Technology, The Netherlands.
Bert
B
van Rietbergen
Research School NUTRIM, Maastricht University, The Netherlands; Department of Rheumatology, Maastricht University Medical Center, The Netherlands; Faculty of Medicine and Life Sciences, Hasselt University, Belgium; Department of Internal Medicine, Viecuri Medical Center Venlo, The Netherlands.
Joop P W
JP
van den Bergh
D015519:Bone Density; D005260:Female; D020342:Finite Element Analysis; D017102:Fracture Healing; D050723:Fractures, Bone / Q000503:physiopathology*; D006801:Humans; D008875:Middle Aged; D014057:Tomography, X-Ray Computed / Q000379:methods*
Distal radius; Fracture healing; HR-pQCT