ABSTRACT
STUDY DESIGN: A retrospective study OBJECTIVES: To evaluate postoperative muscle damage after microendoscopic discectomy (MED) and open discectomy (OD), using analysis of serum creatine phosphokinase (CPK) levels. SUMMARY OF LITERATURE REVIEW: Paravertebral muscle damage after retraction during posterior lumbar surgery can cause postoperative back pain. Serum CPK level is elevated in these patients and may indicate postoperative muscle damage. MATERIALS AND METHODS: We examined 35 cases with MED (group 1) and 11 cases with OD (group 2). Serum CPK levels were checked preoperatively and postoperatively at day 1 and day 3. We analyzed intra-group and inter-group differences in CPK levels according to sex, age, and operation time. Surgical outcomes were evaluated with a visual analog scale (VAS) preoperatively and 1 year postoperatively. RESULTS: CPK levels at postoperative 1 day were increased significantly and decreased significantly at postoperative 3 day in both groups (p<0.05), with levels in group 1 significantly lower than in group 2 (p<0.05). There were no differences in CPK levels according to sex, age, or operation time, except between the 3rd and 5th decades of age at postoperative 1 day in group 2. VAS was significantly different in intra-group analysis (p<0.05) with no significant differences in intergroup analysis. CONCLUSIONS: MED induced a lower increase in serum CPK than OD with similar VAS outcomes. MED results in less postoperative muscle damage than OD, with similar surgical outcomes.