Methylmethacrylate as an adjunct in spinal instrumentation.

Sixteen patients with scoliosis were treated with Harrington-rod instrumentation supplemented by methylmethacrylate fixation at the distraction sites to reduce the possibility of dislodgement of a hook due to inferior bone stock or the patients' inability to cooperate postoperatively because of mental insufficiency or involuntary-movement disorders. Follow-up ranged from six to thirty-eight months (average, fourteen and one-half months). There were no complications related to the use of methylmethacrylate in these patients.

Scoliosis in arthrogryposis multiplex congenita.

Scoliosis was evident in eighteen of eighty-eight patients with arthrogryposis multiplex congenita. The predominant pattern of spinal deformity was a structural thoracolumbar double curve that extended to the sacrum and was associated with pelvic obliquity and lumbar hyperlordosis. Significant contractures about the hips, dislocation of the hip, or both were present in all patients but one. Most of the curves were progressive and they became rigid and fixed at an early age. There was progression of the pelvic obliquity coincident with progression of the curve. Treatment by corrective casts or a Milwaukee brace was ineffective and if surgical treatment directed at the pelvic obliquity did not correct that deformity, spine fusion to the sacrum appeared necessary.

The failure of ethylene oxide gas-sterilized freeze-dried bone graft for thoracic and lumbar spinal fusion.

Thirty-seven patients underwent posterior and/or posterolateral spinal fusion using ethylene oxide gas-sterilized freeze-dried bank bone graft. Thirteen patients had discogenic back pain, eight with prior failed laminectomy procedures, and five undergoing initial spinal surgery. Six patients had isthmic spondylolisthesis, three with associated radicular complaints, and two patients had degenerative spondylolisthesis. Seven patients with spinal fractures and nine patients with scoliosis underwent spinal fusion with associated instrumentation. Pseudarthroses were detected in 28 patients (76%), and 18 patients (49%) underwent pseudarthrosis repair procedures using autogenous iliac bone graft. At surgery, the prior gas-sterilized freeze-dried bone graft was noted to have been almost completely resorbed. Ethylene oxide sterilization has been found experimentally in animal models to damage the osteoinductive ability of bone grafts. Ethylene oxide gas-sterilized freeze-dried bank bone graft is inferior to autogenous bone graft or bank bone graft preserved and/or sterilized by other methods. Its use in thoracic or lumbar posterior or posterolateral fusion cannot be recommended.

Bilateral laminotomy and discectomy for segmental lumbar disc disease. Decompression with stability.

A type of bilateral laminotomy with discectomy for segmental lumbar discogenic disease is presented. The procedure includes wide bilateral decompressive laminotomies and radical partial discectomies, partial V-ostectomy of the adjacent spinous processes, partial facetectomies of the inferior and superior articular processes, and foraminotomies as indicated. One hundred patients who underwent this procedure were evaluated by an independent examiner in follow-up an average of six years postoperatively. The patients were evaluated by utilizing a scale which included back and leg pain relief, restriction of physical activities, analgesic use, and return to work. Seventy patients were graded as good, 12 as fair, and 18 as poor. Preoperative factors which were highly significantly correlated with a good postoperative result included occupation other than heavy labor, present employment or less than 12 months of unemployment, unilateral subjective paresthesias, symptoms of spinal claudication, unilateral restriction of straight leg raising, a positive Cram or bowstring test, the severity of the myelographic defect, elevation of spinal fluid protein, and the severity of the disc pathology noted at surgery. Several other preoperative factors were noted to be of somewhat lesser significance and were correlated with a poor surgical outcome, including job-related injury, compensation or litigation, previous unsuccessful surgery, subjective weakness, calf atrophy, and sensory deficit.

Prone knee-flexion provocative testing for lumbar disc protrusion.

A clinical test designed to help differentiate neurologic from axial back and leg pain is described. The prone knee-flexion provocative test produces or enhances reflex suppression and/or motor weakness secondary to intervertebral disc protrusion. The pathophysiology of this test depends on compression of the spinal nerves, which may occur from a combination of biomechanical factors secondary to lumbar spinal extension. Because this maneuver is required to demonstrate evidence of neural compression, the pathologic condition of the disc is probably mild to moderate and therefore should respond to conservative therapy.

Changes in MMPI profiles after low-back surgery.

Sixty-nine patients who had completed a Minnesota Multiphasic Personality inventory (MMPI) test preoperatively and had had low-back surgery for discogenic disease were seen in follow-up one to 11 years later. Each completed an MMPI test and pain drawing postoperatively, was examined clinically and radiographically, and was rated for surgical outcome. The preoperative MMPI hypochondriasis (Hs) and hysteria (Hy) scales were only modestly related to treatment outcome, but the postoperative scales were strongly related to outcome. Patients with good surgical outcome had lower Hs and Hy scores postoperatively than preoperatively, whereas patients with poor outcomes had higher Hs and Hy scores postoperatively. The MMPI profile of these operated low-back-pain patients was found to be changeable rather than static. The numerical value of the pain drawings was highly correlated with the elevation of the Hs or Hy scales. The MMPI should be utilized to identify patients with neurotic tendencies and prompt referral for psychologic treatment. Those patients who respond favorably to psychotherapy tend to have a better surgical outcome than those with untreated psychoneuroses or those who fail to improve with treatment.

L4-5 degenerative spondylolisthesis. The results of treatment by decompressive laminectomy without fusion.

The results of the treatment of L4-5 degenerative spondylolisthesis by decompressive laminectomy and partial facetectomy without fusion are presented. Patients who met the following criteria were studied: 1) A slip of at least 10%; 2) No compensation/litigation issues involved; 3) No prior surgery; and 4) Follow-up of at least 18 months. Twenty-four patients with an average follow-up of 34 months (range, 18 to 71 months) are reported. The average preoperative slip measured 7 mm (17%; range, 4-12 mm). Sixteen patients, including all patients less than 60 years of age, underwent preoperative supine lateral flexion-extension radiographs for evaluation of instability. No patient had greater than 2 mm of increase in slip on flexion-extension testing. During decompression, the structural integrity of the pars interarticularis and facet joints are preserved. There were 20 good, three fair, and one poor results. The average postoperative slip measured 8 mm (20%; range, 4-11 mm), and no patient had an increase in slip of greater than 4 mm. In the absence of objective instability on preoperative flexion-extension lateral radiographs in L4-5 degenerative spondylolisthesis, decompressive laminectomy with preservation of the structural integrity of the pars interarticularis and articular processes does not require routine spinal fusion and produced satisfactory clinical results.

Intraoperative use of dermatomal somatosensory-evoked potentials in lumbar stenosis surgery.

This report concerns the use of dermatomal somatosensory-evoked potentials (DSEPs) for intraoperative monitoring in the surgical management of a group of patients with lumbar spinal stenosis. Thirty patients with lumbar spinal stenosis underwent preoperative evaluation by DSEPs by use of electrical stimulation of the skin corresponding to the L4, L5, and S1 dermatomes. The specific dermatome to be monitored intraoperatively was selected by correlating those data with physical and radiographic findings and, in certain cases, the results of selective nerve root blocks. Intraoperative baseline (predecompression) DSEP values were obtained after positioning the patient on the operative frame. Monitoring was performed during surgery and post-decompression values were obtained after neural decompression. For six cases of unilateral nerve root decompression, an average 9-msec decrease in latency was noted on the operated side and a 3-msec decrease on the nonoperated side. For 24 cases of bilateral decompression, an average 8-9-msec decrease in latency was noted bilaterally. This method has been found helpful in assessing the adequacy of neural decompression intraoperatively.

The differential utility of the Minnesota Multiphasic Personality Inventory. A predictor of outcome in lumbar laminectomy for disc herniation versus spinal stenosis.

One hundred six patients with disc herniation who underwent lumbar laminectomy and discectomy and 51 patients with spinal stenosis who underwent decompressive lumbar laminectomy were evaluated for surgical outcome at least 1 year postoperatively (mean: 18 months). All had completed the Minnesota Multiphasic Personality Inventory (MMPI) as part of the preoperative evaluation. The Hypochondriasis (Hs), Depression (D), Hysteria (Hy), Psychopathic Deviate (Pd), Psychasthenia (Pt), and Schizophrenia (Sc) scales were found to be predictive of surgical outcome in the herniation group. However, no MMPI scale was related to outcome in the stenosis group. Analysis of covariance showed this fact to be related to the differences in age between the two groups of patients, rather than a result of the differing diagnoses. The MMPI appears to be more useful in predicting surgical outcome in the young and middle-aged adult patient population with disc herniation and is not of predictive utility in the older stenosis population.

Therapeutic trials for low back pain.

Little consensus exists regarding the indications for and effectiveness of many back pain treatments. This clinical uncertainty arises because most back pain research has been flawed by poor methodology. The authors discuss strategies for improving the quality of back pain research on treatment efficacy. Design features, including randomized treatment allocation, independent outcome assessors, comprehensive outcome measures, appropriate statistical analyses, and close patient follow-up can increase study validity. Complete descriptions of enrollment criteria, patient characteristics, and clinical interventions can increase the generalizability of results. Although large scale trials often involve university centers, community-based researchers can collaborate on randomized trials or conduct valuable cohort studies.

Selective nerve root block in patient selection for lumbar surgery: surgical results.

The cause of lumbar radicular symptoms often remains elusive after standard clinical and radiographic evaluation. Selective nerve root block is a useful test to indicate whether the pain is neural in origin and/or whether nerve root is pain producing in these patients with equivocal clinical and imaging studies. Over 8 years, the author performed selective nerve root blocks in 215 patients. Of this group, 78 patients underwent surgery. Following surgery, 71 patients were available for a minimum 12-month follow-up. The preoperative diagnoses included previously unoperated-upon lumbar disc herniation, previously unoperated-upon spinal canal stenosis, and prior lumbar surgery. The average follow-up was 34 months (range, 12-96 months). Overall, there were 38 good (53%), 16 fair (23%), and 17 poor (24%) surgical results. The results for those patients who had had prior surgery were disappointing (52% poor). These data reaffirm that surgical intervention should only be recommended for previously operated-upon patients with unequivocal findings.

A revised objective rating system for patient selection for chymopapain chemonucleolysis.

A revised objective rating system, previously found useful for patient selection for lumbar laminectomy and discectomy, was evaluated in patient selection for chemonucleolysis by intradiscal chymopapain. Based on the severity of findings within each of four categories (neurologic signs, root tension signs, myelogram or computed tomography (CT) findings, and psychosocial environment), numerical scores are derived. A maximum score of 25 points is available in each of four categories for a total of 100 points. The objective rating score was determined in a series of 101 patients prior to treatment of lumbar disc herniation by chemonucleolysis. The patients were evaluated at least one year after injection. The objective rating score was predictive of the result of chemonucleolysis, and was even more strongly predictive of the ultimate surgical outcome, which included the results in 22 patients who were treated by laminectomy after chemonucleolysis failure.

Fracture-dislocation of the lumbosacral spine. Report of a case and review of the literature.

A rare lumbosacral fracture-dislocation occurred in a 22-year-old woman. In a review of the literature describing 17 additional cases, the injury was classified as rare and usually caused by severe trauma. The mechanism of injury is hyperflexion and rotation. In general, attention is drawn to the association of fractured transverse processes as an important clue to the diagnosis. Neural injury is frequent, as are fractures of the lumbosacral facet joints and sacral promontory. Attempts at closed reduction are futile, and the treatment of choice is open reduction and internal fixation with lumbosacral fusion.

Lumbar spinal stenosis: results of surgical treatment.

One hundred forty patients with surgically treated lumbar stenosis were evaluated. There were 70 men and 70 women with an average age of 63 years. The average duration of preoperative leg pain and/or claudication symptoms was 16 months. The average follow-up time was 42 months (range, 12-116 months). Average leg pain improvement was 82%, and average back pain improvement was 71%. Thirteen patients (9%) had no leg improvement, 15 (11%) between 25-74% improvement, and 112 (80%), 75% or greater improvement. Ninety-four patients (67%) had 75% or greater back pain improvement, 29 patients (21%) between 25-74% back pain improvement, and 17 patients (12%) no back pain improvement. Factors significantly correlated with poorer outcome included female sex, the presence of compensation or litigation factors, no relief of symptoms from prior surgical procedures, a diagnostic nerve root block preoperatively, and an objective postoperative sensory deficit.

Patient selection for lumbar laminectomy and discectomy with a revised objective rating system.

A revised objective rating system for patient selection for lumbar laminectomy and discectomy in the treatment of disc herniation is presented. Based on the severity of the findings within each of four categories (neurologic signs, root tension signs, myelogram or CT scan findings, and psychosocial environment), numerical scores are derived. A maximum score of 25 points is available in each category, for a total of 100 points. The objective rating score was determined prospectively in 106 patients who were treated by laminectomy for lumbar disc herniation and who were evaluated at least one year after surgery. The rating score was highly predictive of the surgical result. Application of this system for patient selection would reduce reliance on much of the subjective interpretation of physical and radiographic findings. With appropriate patient selection, improved surgical results are possible.

Lumbar disc herniations: the predictive value of the Health Attribution Test (HAT) and the Minnesota Multiphasic Personality Inventory (MMPI).

Ninety-one patients who were treated for lumbar disc herniation with chymopapain chemonucleolysis were evaluated preoperatively by means of the Health Attribution Test (HAT) and the Minnesota Multiphasic Personality Inventory (MMPI). There were 54 good, 10 fair, and 27 poor results after chemo-nucleolysis. Nineteen patients subsequently underwent lumbar laminectomy and discectomy and the ultimate outcome for the entire series including these laminectomy patients was 66 good, 10 fair, and 15 poor results. The fair/poor chemonucleolysis outcome patients scored significantly lower than did the good outcome patients on the HAT Powerful Others and significantly higher on the Chance scale. Patients with fair or poor outcomes after chemonucleolysis only scored significantly higher on the Hypochondriasis, Hysteria, Psychopathic Deviate, Paranoia, and Hypomania scales in preoperative MMPI testing. Good versus fair/poor ultimate outcome patients differed significantly on preoperative MMPI Hypochondriasis, Hysteria, Psychopathic Deviate, Paranoia, Psychasthenia, Schizophrenia, Hypomania, and Social Introversion scales. These groups also differed significantly on preoperative HAT Internal and Chance scales. Further analyses found the MMPI to be a slightly better predictor of chemonucleolysis outcome and much better predictor of ultimate outcome than the HAT.

Use of the MMPI and MCMI in predicting outcome of lumbar laminectomy.

This study compared the abilities of the MMPI and Millon Clinical Multiaxial Inventory (MCMI), using discriminant analyses, to predict outcome after lumbar laminectomy for chronic back pain. Sixty-nine males and 60 females with lumbar discogenic disease completed MMPIs and MCMIs before surgery and were classified as either having good or fair/poor surgical outcomes based on self-reported pain relief, return to work, restriction of activities, and medication use. Results showed both the MMPI and MCMI to have moderate ability to predict surgery outcome. A slightly higher classification hit rate was obtained with both instruments when age, sex, employment status, and presence of compensation/litigation issues also were entered into the prediction equation. Results indicate the need for caution in using either instrument to make predictions of surgery outcome in individual cases.

Treatment of coccidioidal spinal infection: experience in 16 cases.

Sixteen patients with spinal infection from Coccidioides immitis were treated. Lesion location was cervical in two, thoracic in four, lumbar in six, sacroiliac joint in one, and disseminated spinal in three. The neurological status was intact in 11 patients. One patient had incomplete quadriplegia, three patients had incomplete paraplegia, and a fifth patient had a lumbar root lesion. Treatment was medical only in 4 patients (one of whom required surgery 2 years later) and combined medical and surgical in 13 patients. All patients received amphotericin B intravenously. Follow-up averaged 24 months in 15 patients (range, 12-42 months). The outcome in four patients treated medically alone was one death, one remission, one relapse with disease progression, and one without follow-up. The outcome in the combined medical and surgical group was nine fusions, one pseudarthrosis, and three lesional excisions, all with remission. Successful treatment outcome is disease arrest, as opposed to "cure."