Discectomy for Herniated Lumbar Disc in Resource Limited Settings: Loupe or Microscope?

Background: Loupes and microscopes are common magnification tools used during lumbar discectomy. Objective: In resource limited settings where microscopes are not readily available, we hypothesize that if properly used, magnifying loupes with headlights could offer comparable results to the microscope in relieving leg pain which is the primary goal of discectomy. Patients and Methods: Prospective cohort study was conducted on ninety-seven de novo single level lumbar disc prolapse patients with a predominance of radicular leg pain between January 2009 and September 2014. The microscope was used in twenty-nine patients (29.9%) and loupe with headlight in sixty-eight cases (70.1%). Pre-operative assessment included a thorough clinical examination with a focus on spine assessment. Surgical indications included failure of at least 6 weeks medical treatment, intractable pain or progressive neurological deficits. Same Surgical technique was used in all patients. Per-and post operative parameters recorded included: length of the incision, operative time, blood loss, the presence of a wound drain, length of hospital stay, leg and back pain before discharge and in follow up visits and complications. Pain severity was assessed using the visual analogue scale (VAS). Results: The baseline demographic, clinical, radiological characteristics and surgical technique were similar and comparable (p 0.05). The mean length of the incision was 2.1 cm for the microscope group and 2.8 cm for the loupes group (P value =0.0007). The “loupe” group had more bilateral muscle separation than the “microscope” group (P=0.011). There wasn’t any statistically significant difference in both groups as regard the extent of bony work (p-value=0.09), duration of operation (p=0.85), blood loss (p=1), use of drain in post-operative period (p=0.16), complication rate and length of hospital stay (p=0.21). There wasn’t any statistically significant difference in VAS score for leg pain (p=0.32) and low back pain (p=0.46). Radicular pain recurred in equal proportion in both groups (p=0.17). Twenty-five cases (86.2%) in the microscope and sixty-three cases (92.6%) in the loupe group had a 3 months post-operative VAS of zero (p=0.32). Conclusion: Operative microscope and loupes with headlights are both acceptable alternative tools in lumbar discectomy since both have similar and comparable outcome. In settings with limited access to microscopes, loupes with headlights are safe and effective tools for magnification and illumination in lumbar discectomy..