Article

PURPOSE: To analyze trunk muscle function pre- and postoperatively in patients
undergoing lumbar spine fusion. Associations between changes in trunk muscle
strength and disability were also studied. METHOD: A total of 114 patients
undergoing lumbar spine fusion participated in the study. The flexion and
extension strength of the trunk was measured preoperatively and 3 months after
surgery using a strain-gauge dynamometer. Disability and pain during the past
week was evaluated with the Oswestry disability index (ODI) and visual analog
scale (VAS), respectively. RESULTS: Preoperative trunk extension and flexion
strength levels were 319 N and 436 N in males, respectively, and 160 N and 214 N
in females, respectively. In females 3 months postoperatively, the trunk
extension strength increased by 39 N (p < 0.001) and flexion by 38N (p < 0.001),
whereas it remained unchanged in males. The preoperative extension/flexion
strength ratio was 0.79 in females and 0.76 in males. Three months
postoperatively, the strength ratio decreased to 0.66 in males (p = 0.02). The
mean ODI improved by 47% and back pain decreased by 65% (both p < 0.001). The
changes in the ODI correlated with changes in trunk extension (r = -0.38) and
flexion (r = -0.43) strength. CONCLUSIONS: Patients undergoing lumbar spine
fusion had low trunk muscle strength and strength imbalance. Back fusion surgery
leads to considerable relief of pain and disability, but patients still have low
trunk extension and flexion strength levels 3 months postoperatively. Therefore,
there is need for a proper progressive strength training protocols to normalize
back function.

Langue : ANGLAIS