[The results of percutaneous diskectomy. The course of pain, work capacity and therapy failure].
In a prospective study extending from November 1989 to December 1992 percutaneous discectomy was carried out in 50 patients (26 men, 24 women, mean age 41 [19-73] years). The aim of the study was to ascertain the efficacy of this new mode of treatment, and its indications. The patients selected for the procedure had chronic, therapy-resistant lumboradicular pain syndrome of at least six weeks' duration; imaging procedure had to show a "bulging disc" and neurological deficits had to be no more than minor. During the subsequent follow up period of 22 +/- 9.6 months 35 of the 50 patients did not require any further surgery; 24 of them (69%) resumed full work while seven (20%) regained partial (50%) working capacity. However, the operation proved ineffective in four of these 35 patients (11%). Fourteen of the 50 patients (28%) had persistent pain and required revision by open classical discectomy; seven of them resumed full work and one regained 50% working capacity. The most frequent findings at this revision were stenosis of the subarticular recess in combination with persistent forward bulging of the longitudinal ligament and anulus fibrosus (n = 7), calcification of the posterior longitudinal ligament (n = 1) and an intervertebral disc sequestrum which gave a false negative results on discography (n = 2). In another case there was a genuine recurrence 35 months after a successful percutaneous procedure; this was treated successfully by open operation. When performed at the level L5/S1, the procedure gave unsatisfactory results in five out of six cases.(ABSTRACT TRUNCATED AT 250 WORDS)