Lumbar instability as defined by Pope and Panjabi(1) and Frymoyer and Selby (2) kinematically means an abnormal movement beyond the normal range of motion caused by the applied loads. Due to its weight bearing properties, lumbar spine is more susceptible to degenerative process in advanced-age. The degenerative process normally starts from the intervertebral discs leading to pathologic changes in the ligaments, vertebral bodies and posterior bulging of posterior disk surface, narrowing of the central spinal canal, osteophyte development and sliding of vertebral bodies (3).
The degeneration process leads to the sequential phases of reversible dysfunction, instability characterized by mild disk height reduction, ligament and joint capsule laxity,…show more content… Posterior decompression with PLF is a widely held approach to the surgical management of lumbar instability(8, 9). There were number of studies assessing the effects of posterior decompression and PLF on different lumbar degenerative disease. However, there is still controversy regarding the clinical outcome of those undergoing both decompression and fusion and the use of instrumented fusion.
The Spine Patient Outcomes Research Trial (SPORT) study showed that the patients with degenerative spondylolisthesis who received standard posterior decompressive laminectomy with or without bilateral single-level fusion had better score in SF-36 analysis of bodily pain and physical function in addition to ODI than those treated nonsurgically(10).The results of a 10-year follow up study of 130 patients with degenerative lumbar spinal diseases treated with PLF, showed a satisfactory postoperative recovery in 66.9% of patients and the union rate of 86.5%(11).In a study by Chen et al.(12) on 49 patients with grade I to II degenerative spondylolisthesis, they have found that the group for whom internal fixation in decompression and PLF was used had better outcome with regards to their LBP, spine active function and neurologic function. In Liao et al. (13) study, the ODI has…show more content… When eligible, patients were scheduled for elective surgery. We have filled out a data questionnaire in order to register the patients' symptoms, their pre-operative ODI, radicular pain related VAS score, the 2-year fusion rate and their demographic characteristics including gender, age, body mass index (BMI), occupation, coexisting disease (Diabetes Mellitus (DM), hypertension (HTN), history of trauma and medications. Moreover, the patients’ imaging findings in X-ray (anterior-posterior (AP), lateral, oblique, flexion-extension), MRI and CT-scan were also recorded. Patients were followed at 1, 3, 6 months, 1 and 2 years after surgery. At each follow-up visit, a complete neurological exam was performed. The degree of sagittal and coronal angle correction was also measured. The patients’ LBP was assessed using OLBP scale at each follow-up. Follow-up X-ray was taken if indicated based on the neurologic exam. The OLBP questionnaire composed of 10 sections including pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex life, social life, and traveling; each having 6 questions with the total score of 60. The total ODI score was the percent of patient’s OLBP score of the total score. 0-20% suggests mild pain, 20-40% moderate pain,40-60% severe pain, 60-80%
