THE EFFECTIVENESS OF HEMILAMINECTOMY IN SINGLE LEVEL LUMBAR SPINAL STENOSIS

Abstract

Degenerative spinal stenosis is a progressive disorder that involves the entire spinal motion segment. It describes abnormal narrowing of the central canal, the lateral recesses or the intervertebral foramina to the point where the neural elements are compromised. When this occurs the patient develops neurological symptoms and signs in the lower limbs. Hemi-laminectomy is a surgical procedure, which is designed to relieve pressure on the nerves in the spine. This procedure is performed when patient has degenerative conditions leading to signs and symptoms of neural impairment, because the procedure is invasive, it is usually only recommended when other non-operative treatment approaches failed to relief the patient complain. Before the procedure can be performed, a neurological examination is conducted to determine which area of the spine is affected. We also typically order medical imaging studies of the spine so that we can clearly visualize the area that requires surgery. The patient undergoes routine blood work to check for underlying medical problems that could complicate surgery, and meets with an anesthesiologist to discuss anesthesia options and prepare for the operation. This study is a prospective analysis of a randomized collection of 22 patients who underwent surgery for lumbar spinal stenosis at the period from April to the end of July 2012. The procedures were done by orthopaedic surgeons. The period of the follow up was 1 year post-operatively. The follow up criteria depended on the distance the patient could walk uninterrupted for the assessment of the neural claudication, for the assessment of the radicular pain; we depended on the Outcome Measure in Lumbar Spinal Stenosis questionnaire (OMLSS) which is rating from 6 to 30, & for the weakness (weak dorsiflexion) we depended on the Medical Research Council (MRC) Grading of the muscle power, which is rating from 0 to 5. The patients were suspected to have spinal stenosis on the basis of a history, physical examination, & radiological imaging. The final assessment and the decision of the operation were made by the surgeons who operated them. Twenty two patients were included in the study, 15 of them were females (68%), and the rest were males (32%), with female to male ratio was approximately 2:1. Regarding the age, it was ranging from (55 - 78 years); the majority 14 of 22 of patients (63%) was between the ages of 61 – 65 years old. About the occupation, (50%) of the total number were housewives women & 18% of the total number were earners men. (77%) & (23%) of the patients were complaining of bilateral & unilateral neural claudication respectively, (64%) & (36%) of the patients had bilateral & unilateral radicular pain & paraesthesia respectively, (23%) & (13%) had bilateral & unilateral weak dorsiflexion respectively, who were in grade 3 according to the (MRC) grading system. Post-operatively, (81.8%) of the patients with neural claudication got improvement in the walking distance for up to more than 1 km uninterrupted. Regarding the radicular pain, (59%) had subsided in less than 3 months post-operatively, (27.5%) of them were relieved in the period of 3 - 6 months, & just one patient (4.5%) still had pain for the entire period of the follow up which was rated 15 of 30 according to the (OMLSS). Weak dorsiflexion was also improved post-operatively in the 1st 3 months in (33.3%) & (40%) of the unilaterally & bilaterally affected patients respectively, while (67%) & (60%) of the unilaterally & bilaterally affected patients relieved in the period up to the 6th month post-operatively respectively.