Predictive Factors for Muscle Injury After Posterior Lumbar Spinal Surgery.

OBJECTIVE

The aims of this study were to evaluate the risk factors for muscle injury in patients undergoing posterior lumbar spinal surgery and the clearance of postoperative biochemical changes following lumbar fusion and secondarily to evaluate the timing for monitoring postoperative biochemical serum levels and potential clinical correlation.

METHODS

The study prospectively enrolled 39 patients with degenerative disease of the lumbar spine. Biochemical markers (creatine phosphokinase [CPK], creatinine, and hemoglobin) were analyzed in 5 predefined stages. All relevant clinical data were collected. Rhabdomyolysis (RML) was defined as a postoperative 5-fold increase of the baseline CPK value.

RESULTS

Patients from the lumbar fusion group had the highest postoperative CPK ratio. Overall, the rate of RML was 43.6%. CPK and creatinine activity reached their maximum on the first postoperative day in 69.2% and 87.5% of patients, respectively. Lumbar fusion (P = 0.005), surgical time >270 minutes (P = 0.028), and fall in hemoglobin levels >3 g/dL (P = 0.034) were identified as independent factors associated with higher risk of RML.

CONCLUSIONS

The risk of RML increases with prolonged and invasive surgery with higher bleeding potential. Knowing the clearance of postoperative biochemical changes permits a standardized strategy with measurements in precise intervals, thereby avoiding unnecessary costs. The clinical significance is still undetermined.