ANALYSIS OF LUMBO-SACRAL DISC PROLAPSE NEUROSURGICAL INTERVENTION

Background: Low back pain is a common cause of pain and there are many causes. Finding the exact cause of the pain can help guide treatment and management. Objective: To evaluate the clinical presentation, diagnosis and surgical outcome of the treated patients with lumbar-disc prolapse. Patients and Methods: Patients selection done using neuroimagings like plain radiographs and MRI Scan of lumbosacral spine. The surgical procedures applied were laminectomy, foraminatomy and evacuation of herniated disc material. Patients were analyzed postoperatively for outcome according to the symptoms resolved after surgery, objective clinical examinations and imaging studies. Results: Fifty five patients, 25 (45%) males and 30 (55%) females. Predominant clinical presentation were low back pain with radiation to leg 36(65.4%), neurogenic claudication in 15 patients (27%), and neurological deficit (foot drop) 4 about (7.2%). Seventy four percent (about 41) of the herniated disc were found at L4 L5 and L5 SI levels. Rate of complications were 12.7% (about 7) with 4 cases infections and 3 with dural tear repaired intraopertively being commonest. Excellent to good surgical outcome were found in 90% (about 50) of the cases. Conclusion: The results of the study depend mainly on selection of patients. Traditional laminectomy and discectomy still play a benefit for major group of patients. For aminatomy, opening of roots foramen adds a benefit for the results.


INTRODUCTION:
Low back pain is a common cause of pain and there are many causes.Finding the exact cause of the pain can help guide treatment and management.Muscle strains, joint related problems, bony pathologies, disc problems and other conditions such as infections are all causes of low back pain.However, a common cause of low back pain can be due to 'degeneration', or wearing out of the lumbar intervertebral discs.The resulting condition is called lumbar disc pain 16,17 .
Symptoms of a prolapsed disc may vary, depending on the location of the herniation and the types of soft tissue that become involved.They can range from little or no symptom if the disc is the only part affected, to severe and agonizing low back pain that will radiate into the regions served by affected nerve roots that are irritated or compressed by the herniated disc material.Often, prolapsed discs are not diagnosed immediately, as the patients present with undefined pains in the thighs, knees or feet.Other complaints may include sensory changes such as numbness, tingling, muscular weakness, paralysis, paresthesia and impairment of the reflexes.If the prolapsed disc is in the lumbar region the patient may also experience sciatica which is due to irritation of one of the nerve roots of the sciatic nerve 27,28 .Unlike a pulsating pain or pain that comes and goes, which can be orginated from muscle spasm, pain from a prolapsed disc is usually continuous or at least is continuous in a specific position of the body 30 .
Lower backache with or without sciatica is a major cause of morbidity worldwide.Lumbar disc herniation ("slipped disc") accounts for less than 5% of all low back problems, but it is the most common cause of nerve root pain ("sciatica").Ninety percent of acute attacks of sciatic pain settle with conservative management.However clinically significant sciatic pain due to disc prolapse occurs in 4-6% of the population 1 .The degeneration of intervertibral disc due to a combination of factors can result in herniation, particularly at levels of L4 L5 and L5 S1 in more than 90% of the cases.The L3\L4 and L2\L3 accounts for the majority of remaining disc herniations 2 .The presence of painful radiculopathy and other symptoms depend on the site and degree of disc herniation, detailed history, physical examination supplemented by neuroimaging can differentiate herniated lumbar disc prolapse from other causes of low back pain and sciatica 3 .Absolute indications for surgery include altered sphincters function and progressive muscle weakness, but these are rare presentations.The usual indication for surgery is to provide more rapid relief of pain and disability in the minority of patients whose recovery is unacceptably slow.The outcome from disc surgical management depends upon the number of factors; the most important is the careful selection of the patients 4 .

PATIENTS AND METHODS
A prospective study conducted at the department of Neurosurgery, Alkadhymia Teaching Hospital from 1 st August 2008 to 1 August 2010.Data of the patients included, age, sex, detailed history of low back pain, findings of clinical examination, details of routine baseline investigations, neuroimagings, and operative procedures, postoperative complications and surgical outcome.
Neuroimaging included plain radiographs and MRI of lumbosacral spine.Patients in the study group presented with various clinical features such as Cauda Equina syndrome, progressive neurological deficit, and profound neurological deficits such as foot drop, severe and disabling pain refractory to 4-6 weeks of conservative treatment.Conservative treatment consisted of bed rest, drug therapy both steroid and nonsteroid anti-inflammatory agents followed by physiotherapy.The criteria for selection of the patients were strictly adhered and standard surgical technique were used (laminectomy, and removal of prolapsed disc material) 4 .All surgeries were performed by the authors.Postoperatively patients were analyzed for outcome according patient symptoms resolved after surgery, objective examinations and radiographic imaging studies including dynamic study to establish vertebral instability.

RESULTS
In this study a total of 55 patients were studied and result analyzed with the youngest being of 18 years age and oldest 65 years.Majority of the patients were between 31 to 45 years age group .Table (1).Male to female ratio was 1:1.2.Low back pain with radiation to lower limbs was the predominant mode of presentation as shown in Table 2.

40%
no response after surgery

DISCUSSION
Management of lumbar disc herniation has been extensively studied because of its economic impact in the society [1][2][3] .
Age group: affected in this study was between 30 to 45 years, hard workers and the main bread earners of families.

Level of disc prolapse:
The reported frequency of occurrence of lumbar disc prolapse is highest at L4 \L5 and L5\SI levels in 90% of the cases 2 while in our study it was seen at these levels in 72.5% of the cases.In the upper lumbar spine extraforaminal space is proportionally larger than in the lower lumbar levels, other factors contributing to disc prolapse are increased mobility of lower segments resulting in earlier degeneration and disc prolapse 6 .
Diagnostic study: MRI scan is the gold standard investigation for diagnosis of disc prolapses 7 .The major findings on plain radiographs of the patients with prolapsed disc are a decreased disc height.Radiographs have a limited diagnostic value because degenerative changes are age related and are equally present in symptomatic and asymptomatic cases 7 .MRI scan may show bulging of degenerative discs in asymptomatic cases because of its high sensitivity; therefore any management decision should be based on the clinical findings corroborated by diagnostic test results 8 .
The treatment: of lumbar disc prolapse is the most controversial topic in the spine literature, as to whether surgical treatment should be attempted and if so which surgical approach is optimal.Since 1934, surgical treatment for lumbar radiculopathy due to disc prolapse has consisted of laminectomy and removal of herniated material, which is called the standard surgical procedure 4 .In our study, laminectomy and foraminatomy done in most of the patients.
Outcome: of disc surgery generally is good; factors that predict the success or failure of lumbar disc surgery have been determined 10,11 .
In general patient's selection appeared to be the most important factor to achieve good results.
Approximately 80-90% have good results with traditional laminectoray and diskectomyt 12,13 .In our study 50% of the patients had excellent results while 40% good results, most of the patients presented for surgery after utilizing all other modes of therapies for at least 4 to 6 weeks except surgery.
Complication rate: infection in 7.2%, two patient with superficial wound infection with got recovery and two with descitis one with very good recovery.A cauda equina syndrome remains an absolute indication for urgent surgery.In the series of Buchner and Schiltenwolf1 4 , 12 of 17 patients had a complete recovery of urinary function.In our study 1 out of 4 patients had good control over urinary sphincters while 1 got partial control (stress incontinence) after 6 months of follow up.Motor deficit such as foot drop recovery was very slow and incomplete.One out of 4 cases had good recovery, and 3 had no improvement after 6 months of follow up, indicating long term capacity of recovery.Those three patients had foot drop of more than 3 months duration preoperatively.

CONCLUSSION
1.The results depend mainly on selection of patients.
2. Traditional laminectomy and discectomy still play a benefit for major group of patients.
3. Foraminatomy, openining of roots foramen adds a benefit for the results of laminectomy

Table 1 :
Age and sex distribution of patients

Table 3 :
Site of disc prolapse

Table 4 :
The outcome