Comparative Study of Microdiscectomy and Automated Percutaneous Discectomy in Lumbar Disc Herniation

Joo, Kyo Sung; Shin, Won Han; Kim, Bum Tae; Choi, Soon Kwan; Byun, Bark Jang

Abstract

Aretrospective study on operative results was carried out in a series of 164 patients who were performed by microdiscectomy and 57 patients by automated percutaneous lumbar discectomy(APLD) for herniated lumbar discs between January 1, 1990 and June 30, 1996. The operative results were analysed, and the correlation between preoperative clinicoradiological factors and postoperative clinical results were statistically assessed. The major results were as follows: 1) Of 164 microdiscectomy cases, 102 were males and 62 were females, mean age was 42.4 years and incidence was the highest in the 5th decade. Among 57 APLD cases, 43 were males and 14 females, mean age 32.2 years, and the highest incidence in the 3rd decade. 2) The preoperative symptoms and signs in microdiscectomy and APLD cases were lumbago(98.2% vs 98.2%), radiating pain(96.3% vs 98.2%), positive straight leg raising test(77.4% vs 70.2%), motor weakness(27.4% vs 17.5%), claudication(13.4% vs 0%) and voiding difficulty(2.4% vs 0%). 3) Number of operated levels were 226 in microdiscectomy and 74 in APLD. The most commonly operated levels in both groups were L4-5. 4) Operative results. (1) The overall success rates by Prolo's scale were 87.1% in microdiscectomy and 80.7% in APLD, respectively. (2) In younger age group(below 30 years) and in non-compensatory group, success rates were significantly higher in microdiscectomy(100%, 89.9% vs 76.7%, 62.5% respectively). (3) As to protrusion and degeneration on MRI, a clinical result, from patients with mild to moderate protrusion and degeneration of discs was significantly better in microdiscectomy group, and that of mild protrusion and degeneration of discs in APLD group was significantly better. (4) The most common cause of failure was inadequately removed disc material in microdiscectomy cases and operated for sequestered discs in APLD cases. There results indicate that there were no differance in overall success rates between microdiscectomy and APLD. But it should be emphasized that clinical results may have been influenced by age, existence of compensation, and the degree of protrusion and degeneration of discs as prognostic factors. The authors believe that if the selection of operative procedure is carefully decided with details of clinical and radiologic findings of the patients, a good outcome can be expected.