Abstract

Introduction:Degenerative lumbar central stenosis with compression of neural structures may lead to clinical symptoms as neurogenic claudication with radicular signs. Spinal decompression can reduce symptoms of neurological deficits in lumbar spinal stenosis. In this respect, decompression, fusion or a combination of the two procedures are to be considered due to the possible leg and back symptoms. The use of microsurgical techniques has reduced tissue damage and its consequences. The goal of this prospective, randomized, controlled study was to compare the surgical results in degenerative lumbar central stenosis with full-endoscopic interlaminar bilateral technique with unilateral approach (FI) with those of a conventional microscopic-assisted technique (MI).Material and Method:160 patients with clinically-symptomatic degenerative lumbar central stenosis underwent surgical decompression. 80 Patients were operated in full-endoscopic interlaminar bilateral technique with unilateral approach in over-the-top technique (FI) and 80 Patients with conventional microscopic-assisted bilateral laminotomy technique (MI). Inclusion criteria were monosegmental central stenosis with predominant leg symptomatic, neurogenic claudication with or without paresis, back pain max. 20/100 on the VAS, conservative therapy exhausted or no longer indicated due to the symptoms. The full-endoscopic operation was performed with 9.9-mm endoscopes with 6.1 intra-endoscopic working canal. The follow-up was 24 months. 135 patients were followed. Additionally to general parameters validated scores were used.Results:72 % of the patients had postoperatively no longer leg pain or it was nearly complete reduced. 21.2 % had occasional pain. The clinical results were similar in both groups. The rate of complications and revisions was significantly reduced in the FI group. 11 Patients showed transient postoperative dysaesthesia (7 x MI, 4 x FI), 4 Patients had transient urinary retention (3 x MI, 1 x FI), Dura injuries occurred in 5 Patients (4 x MI, 1 x FI); 3 Patients (2 x MI, 1 x FI) showed a increase in preoperatively-existing foot dorsiflexion paresis. One Patient (MI) required revision because of epidural haematoma, 5 Patients delayed wound healing (5 x MI). Apart from transient dysaesthesia and transient urinary retention, the complication rate was 8.8 % (MI = 12,5 %, FI = 5 %) and was significantly higher in the MI group (p < 0.05). 4 patients (3 x MI, 1 x FI) required revision surgery due to persistent leg pain and/or progredient back pain, 3 (2 x MI, 1 x FI) of these additionally underwent fusion.Conclusion:Within the indication criteria, the full-endoscopic interlaminar bilateral decompression with unilateral approach is a safe supplement and potential alternative to the conventional microscopic-assisted bilateral laminotomy-technique. The full-endoscopic technique shows advantages in the following areas: operation, complications, traumatisation, rehabilitation. It enables selective procedure with direct visualization, sufficient decompression and less traumatization of the access pathway and the spinal canal structures with all advantages of a minimally-invasive intervention.