Mukhergee G. S1, Kiran Kumar L2, Manikumar C. J3
BACKGROUND
Spinal stenosis is one of the most common conditions in the elderly. It is defined as a narrowing of the spinal canal. The term stenosis is derived from the Greek word for narrow, which is “Stenos”. The first description of this condition is attributed to Antoine portal in 1803. Verbiest is credited with coining the term spinal stenosis and the associated narrowing of the spinal canal as its potential cause.[1-10] Kirkaldy–Willis subsequently described the degenerative cascade in the lumbar spine as the cause for the altered anatomy and pathophysiology in spinal stenosis.[11-15] If compression does not occur, the canal should be described as narrow but not stenotic. Some studies defined lumbar spinal stenosis as a “narrowing of the osteoligamentous vertebral canal and/or the intervertebral foramina causing compression of the thecal sac and/or the caudal nerve roots; at a single vertebral level, narrowing may affect the whole canal or part of it” (Postacchini 1983). This definition distinguished between disc herniation and stenosis.[16]. The most common type of spinal stenosis is caused by degenerative arthritis of the spine. Hypertrophy and ossification of the posterior longitudinal ligament which usually are confined to the cervical spine, and diffuse idiopathic skeletal hyperostosis (DISH) syndrome also may result in an acquired form of spinal stenosis. Congenital forms caused by disorders such as achondroplasia and dysplastic spondylolisthesis are much less common. Congenital spinal stenosis usually is central and is evident or imaging studies. Idiopathic congenital narrowing usually involves the anteroposterior dimension of the canal secondary to short pedicles; the patient otherwise is normal. In contrast, in achondroplasia, the canal is narrowed in the anteroposterior plane owing to shortened pedicles and in lateral dimension because of diminished interpedicular distance. Acquired forms of spinal stenosis usually are degenerative. This process is most commonly localised to the facet joints and ligamentum flavum, with the resultant arthritic changes in the joints visible on radiographic studies. Frequently, these abnormalities are symmetrical and bilateral. The L4-L5 level is the most commonly involved, followed by L5-S1 and L3-L4 disc herniation and spondylolisthesis may exacerbate the narrowing further.
1.
METHODS
This study was taken up to evaluate the management of lumbar spinal canal stenosis cases. The study was conducted from May 2012 to October 2014: A total of 86 patients of 55-70 age groups with degenerative LCS were followed prospectively from May 2012 to October 2014. All the treatment methods were explained to patients and treatment method was determined by patient’s choice. The sample is divided into two groups 42 surgical and 44 conservative based on patient’s preference.
MEASUREMENT OF OUTCOME
Outcomes were measures of bodily pain and physical function on the medical outcomes study 36-item short-Form General Health Study (SF-36) 22-25 and on the modified Oswestry Disability Index 26 measured at 6 weeks, 3 months, 6 months, and 1 year and 18 months. SF-36 scores range from 0 to 100 with higher scores indicating less severe symptoms. The Oswestry Disability Index ranges from 0 to 100, with lower scores indicating less severe symptoms.
STUDY INTERVENTION
The protocol surgery was standard posterior decompressive laminectomy operated by three surgeons. The type of nonsurgical care included physical therapy (68% of patients), epidural injections (56%), the use of anti-inflammatory drugs (55%) and use of opioid analgesics (27%). Informed consent was taken from every patient after explaining the particulars of study interventions.
In this study, 82% patients (n=70) were in age group 50-59 years with an average age of 50.2 years with a total sample size of 86 patients followed by 60-69 years age group. Both the surgical and conservative groups had similar sex distribution. Initially, the selection criteria for the study was formulated based on predetermined inclusion and exclusion criteria. All the patients are suffering from symptoms form a duration ranging from 6 months to 2 years with an average duration of 15 months. All the patients are having intermittent neurologic claudication or radiculopathy and sensory symptoms correlating with MRI study. The process of evaluation was explained to patients and informed consent was taken. For evaluating outcomes of treatment ODI, SF 36 BP, SF36 PF was used.[17,18,19] The baseline values are similar in both surgical and conservative groups for above mentioned 3 clinical assessment parameters. Treatment outcome was measured by “Change in Mean” of these parameters after periodic evaluation and statistical significance was also calculated. While evaluating outcomes the predominant difficulty faced is loss to follow-up due to non-adherence and cross over between group and these patients were excluded from study which resulted in a sample size of 86 (Surgical – 42, Conservative – 44). This study showed significantly more improvement in all outcomes such as pain and function in patients treated operatively compared with those treated non-operatively.For assessment of disability in this study with regard to the choice of the measure of disability, the ODI (Oswestry Disability Index) was opted as it is a simple, condition specific, preferred multidimensional tool with the advantage of easy patient comprehension and compliance. This self–assessment test takes less than 5 min. to complete and 1 min. to score with no training, equipment or cost requirements; and it covers a wide range of function, pain. The national translated version of the ODI questionnaire used in this study was easily comprehended. Studies have reported that this short, self-administered questionnaire is reproducible, reliable, internally consistent, and valid and is an adequately useful instrument for the assessment of disability in patients with lower back pain.
The other parameters i.e. SF 36 BP, SF 36 PF (Used in this study) have also been used in SPORT study, main stenosis study.[17,18]
2. RESULTS
This study was taken up to evaluate the management of lumbar spinal canal stenosis cases. The study was conducted from May 2012 to October 2014: A total of 86 patients of 55-70 age groups with degenerative LCS were followed prospectively from May 2012 to October 2014. All the treatment methods were explained to patients and treatment method was determined by patient’s choice. The sample is divided into two groups; 42 surgical and 44 conservative based on patient’s preference. Gender distribution in sample population was 75% male, 25% females. Most of the patients have more than one component. 47% patients had central canal stenosis and 48% had lateral, 32% far lateral stenosis. The mean operative time was 128 minutes. The mean operative blood loss was 293 mL. Average hospital stay was 15 days. 2% patients had dural tear, 11% patients had superficial surgical wound infection, which was treated by topical antiseptics. No complications were observed in conservative treatment. 34% patients received NSAID, 18% received ESI, 27% received PT, 15% received combined treatment. Assessment of ODI, SF 36 BP, SF 36 PF in study population and values are expressed in terms of mean and treatment effect/outcome was measured in terms of change in mean. Baseline mean values of surgical and conservative groups are similar. At periodic follow-ups, mean change is more in surgical group than conservative group. Hence, it is concluded that mean is effectively changed in surgical group than conservative groups.
CONCLUSIONS
Radiologic stenosis correlates poorly with clinical disability. As such, a thorough clinical examination of patients with lumbar spinal stenosis, including assessment of psychosocial factors, is crucial in determining the treatment outcome. The treatment effect for surgery was seen as early as 6 weeks. Appeared to reach a maximum at 6 months, and persisted for 18 months. The condition of patients in the non-surgical group improved only moderately during the 18-month period. Results in both groups were stable during every follow-up throughout the period of study i.e. from 6 weeks to 18 months. No catastrophic events arose among the patients receiving conservative treatment. De compressive surgery (Laminectomy) is more effective than conservative treatment for radicular pain due to lumbar spinal canal stenosis. The functional effectiveness of surgery for pain and disability was sustained and more on comparison with conservative treatment. Those treated surgically showed significantly greater improvement in terms of function and self-rated progress over 18 months compared to patients treated nonoperatively in terms of ODI index, SF 36 BP, SF 36 PF scores.
