gms | German Medical Science

Objective: Open discectomy is the standard operation for lumbar herniated intervertebral disk disease (HIVD). PELD have shown not-inferior outcome to open discectomy and the interest on the PELD seems to be increasing. However, PELD may not be an applicable option for all ages. The object of the present study was to provide an age cut-off of percutaneous endoscopic lumbar discectomy (PELD) for optimal reoperation rate with national-based population based data.

Method: We selected 15,817 patients who underwent open discectomy (n = 12,816) or PELD (n = 3,001) in 2003 from Korean Health Insurance Review & Assessment Service (HIRA) database. All patients in the cohort were followed until December 31, 2008, and the minimum follow-up period was 5 years. A time to event survival analysis was performed. Primary end-point was any type of second lumbar spine surgery during the follow-up period. Minimum P-value approach and two-fold cross validation approach were utilized to determine an age cut-off point.

Results: The optimal age cut-off point was determined as 57 years. PELD for elder patients (= 57 years) had a higher reoperation risk during postoperative 3.4 years (Hazard ratio [HR] at 1 yr, 1.75; 2 yr, 1.57; 3 yr, 1.41). However, re-operation risk was not higher after PELD for patients of < 57 years from 1.9 years than open discectomy (HR at 2 yr, 0.86; 3 yr, 0.78; 4 yr, 0.70; 5 yr, 0.63).

Conclusions: In the present study, we showed that an age cut-off point of PELD for optimal reoperation rate may be 57 years with national-wide population based data. Reoperation rate seems to be not higher for patients younger than 57 years after PELD than open discectomy, but applying PELD for elder patients need careful consideration.