Validity of outcome measures used in randomized clinical trials and observational studies in degenerative lumbar spinal stenosis.

It is unclear whether outcome measures used in degenerative lumbar spinal stenosis (DLSS) have been validated for this condition. Cross-sectional analysis of studies for DLSS included in systematic reviews (SA) and meta-analyses (MA) indexed in the Cochrane Library. We extracted all outcome measures for pain and disability. We assessed whether the studies provided external references for the validity of the outcome measures and the quality of the validation studies. Out of 20 SA/MA, 95 primary studies used 242 outcome measures for pain and/or disability. Most commonly used were the VAS (n = 69), the Oswestry Disability Index (n = 53) and the Zurich Claudication Questionnaire (n = 22). Although validation references were provided in 45 (47.3%) primary studies, only 14 validation studies for 9 measures (disability n = 7, pain and disability combined n = 2) were specifically validated in a DLSS population. The quality of the validation studies was mainly poor. The Zurich Claudication Questionnaire was the only disease specific tool with adequate validation for assessing treatment response in DLSS. To compare results from clinical studies, outcome measures need to be validated in a disease specific population. The quality of validation studies need to be improved and the validity in studies adequately cited.

Surgery for lumbar disc herniation: Analysis of 500 consecutive patients treated in an interdisciplinary spine centre.

Surgical removal of a symptomatic herniated lumbar disc is performed either with or without the support of a microscope. Up to the time of writing, the literature has reported similar clinical outcomes for the two procedures. Five hundred consecutive patients, operated upon for primary single-level lumbar disc herniation in our University Spine Center between 2003-2011, with (n=275), or without (n=225), the aid of a microscope were included. Data were retrospectively analyzed, comparing the primary endpoint of clinical outcome and the secondary endpoints of complications, surgical time and length of hospitalization. Clinical outcomes and reoperation rates were comparable in both groups. Surgical time was significantly shorter with a mean time of 47minutes without use of the microscope compared to the mean time of 87minutes (p<0.001) with the use of the microscope. Mean length of hospitalization was shorter in those operated with the microscope (5.3days) compared to those without (6.1days, p=0.004). There was no difference in rates of complications. Microdiscectomy versus open sequestrectomy and discectomy for surgical treatment of lumbar disc herniation is associated with similar clinical outcomes and reoperation rates. Open sequestrectomy is associated with shorter operation times. Microdiscectomy is associated with shorter hospitalization stays.

Intraoperative high frequency ultrasound in intracerebral high-grade tumors.

PURPOSE: To demonstrate the utility of a new concept of intraoperative use of high frequency ultrasound (hfioUS) in maximizing the extent of resection (EOR) of intracerebral high-grade tumors. MATERIALS AND METHODS: 22 Patients harboring an intracerebral high-grade tumor were retrospectively included in this study (14 primary tumors, 8 metastasis). 14 of them had a perilesional edema equal or greater to lesion volume, 3 had previously received radiotherapy. Following macroscopic tumor debulking, the small (11 × 31 mm) L15 - 7io (Philips, Bothell, USA) high-frequency probe (7 - 15 MHz) was introduced into the resection cavity and its walls were meticulously scanned to search for tumor remnants. Postoperative MR scan was evaluated by a board-certified independent neuroradiologist, who assessed the EOR. RESULTS: Gross total resection was achieved in 21 patients (95.5 %). One patient had a small tumor remnant (6 × 4 × 3 mm) of a very large (80 × 60 × 74 mm) anaplastic astrocytoma, detected in the postoperative MR scan. A permanent postoperative hemiparesis was diagnosed in one patient with a metastasis in the motor area, while the other patients recovered without permanent neurological deficits from the surgery. CONCLUSION: The hfioUS probe allowed in this study a precise detection of the tumor and a detailed discrimination between normal, pathological and edematous tissue in all 22 cases.