Robert B. Winter

The surgical and medical perioperative complications of anterior spinal fusion surgery in the thoracic and lumbar spine in adults. A review of 1223 procedures.

Study Design A retrospective review of 1223 thoracic and lumbar anterior spinal fusions was performed from 1969 through 1992. Objectives To document the incidence and specific types of perspective complications related to anterior spinal fusions. Summary of Background Data Despite the increased use of anterior spinal surgery, there has been little documentation of the specific types and frequencies of the complications associated with its use. Methods All Minnesota Spine Center patients age 18 years or older who had anterior spinal fusions between the levels of T1 and S1 from August 1969 to June 1992 were reviewed for the occurrence of perioperative complications. Surgical approach and technique and associated comorbidity was recorded. Results The risk of a complication was increased for patients over age 60 years, for women, and for patients with multiple preexisting health problems. Serious complications, such as death (0.3%), paraplegia (0.2%), and deep wound infection (0.6%) were rare. The complication rate for complications that were directly attributed to the anterior spinal surgery was 11.5%. Conclusions Anterior spinal fusion surgery is a safe procedure and can be used with confidence when the nature of a patients spinal disorder dictates its use. Complications are often approach specific.

Complications Associated with Pedicle Screws

BACKGROUND The safety and the effectiveness of pedicle-screw instrumentation in the spine have been questioned despite its use worldwide to enhance stabilization of the spine. This review was performed to answer questions about the technique of insertion and the nature and etiology of complications directly attributable to the screws. METHODS We performed a retrospective review of all of the pedicle-screw procedures that were done by us from January 1, 1984, to December 31, 1993. We inserted 4790 screws during 915 operative procedures on 875 patients; 668 (76.3 percent) of the patients had a lumbosacral arthrodesis. The mean duration of follow-up was three years (range, two to five years). The accuracy of screw placement was assessed on intraoperative, immediate postoperative, and follow-up radiographs with use of a technique that was developed by one of us (F. D.); this technique has yet to be validated to determine the prevalence of various types of error. RESULTS Of the 4790 screws, 4548 (94.9 percent) had been inserted within the pedicle and the vertebral body. One hundred and thirty-four (2.8 percent) of the screws had perforated the anterior cortex, and this was the most common type of perforation. One hundred and fifteen (2.4 percent) of the screws were associated with complications that could be ascribed to the use of pedicle screws. The most common problem was late-onset discomfort or pain related to a pseudarthrosis or perhaps to the screws; this problem was associated with 1102 (23.0 percent) of the screws, used in 222 (24.3 percent) of the procedures. The symptoms necessitated removal of the instrumentation with or without repair of the pseudarthrosis. A pseudarthrosis was found during forty-six (20.7 percent) of the 222 procedures. Irritation of a nerve root occurred after nine procedures (1.0 percent) and was caused by eleven screws (0.2 percent); it was more commonly caused by medially placed screws. Three patients had residual neurological weakness despite removal of the screws. Twenty-five screws (0.5 percent), used in twenty procedures (2.2 percent), broke. The screws that broke were of an early design. A pseudarthrosis was found in thirteen of twenty patients who had broken screws. Sixteen of the twenty patients had an exploration; three of them were found to have a solid fusion, and thirteen were found to have a pseudarthrosis. The remaining four patients had evidence of a solid fusion on radiographs and had no pain. CONCLUSIONS There are few problems associated with the insertion of screws, provided that the surgeon is experienced and adheres to the principles and details of the operative technique. Our review revealed a low rate of postoperative complications related to pedicle screws. The problem of late-onset pain may be related to the implants or to the stiffness of the construct; however, it is difficult to accurately identify its exact etiology.

The Milwaukee Brace for the Treatment of Adolescent Idiopathic Scoliosis. A Review of One Thousand and Twenty Patients.

We reviewed the medical records and roentgenograms of 1020 patients who had been managed for adolescent idiopathic scoliosis, between January 1954 and December 1979, with a Milwaukee brace; we wished to determine whether use of the brace had effectively altered the natural history of the disease. The findings were considered with respect to a previous study of 727 children who had had comparable curves and had not initially been managed with the brace but had been followed for progression of the curve, during the same time-span as that in the current study. Of those 727 patients, 558 (77 percent) had no progression of the curve. The average age of the 1020 patients at the time that treatment with the brace was begun was thirteen and one-half years (range, ten to seventeen years). None of the patients had received any other treatment, and all had been managed only by the physicians participating in this study. In both the current and the earlier series, the outcome was considered a failure if the curve had increased 5 degrees or more; in the patients in the current study, who were managed with the brace, the outcome was also considered a failure if operative intervention had been needed. Of the 1020 patients in the current series, 229 (22 percent) had operative intervention; this rate was higher in the patients who had a curve of more than 30 degrees at the time of bracing and in those who had a Risser sign of 0 or 1. The 791 remaining patients, who were managed with the brace only, had a mild improvement of 1 to 4 degrees at the time that use of the brace was discontinued (the difference being within the margin of error of measurement). With respect to curves of between 20 and 39 degrees, the rate of failure was lower in the current series of patients who had been managed with the brace than in the earlier series of patients who had not been thus managed but had been followed for progression. Progression of the curve was found to be related to the pattern and magnitude of the curve; the age of the patient at the time of presentation; the Risser sign; and, in girls, the menarchal status. We recommend that immature adolescents who have a curve of more than 25 degrees and a Risser sign of 0 be managed with a brace immediately, rather than after progression has been documented.

Harrington instrumentation without fusion plus external orthotic support for the treatment of difficult curvature problems in young children.

In selected patients a method of rod insertion without fusion combined with use of a full-time external orthotic support, e.g., the Milwaukee brace, is effective. The orthopedic surgeon confronted with young children who have curves that do not respond to conservative treatment alone or in which bracing is contraindicated should find this procedure particularly suitable. The method allows for the expression of full growth potential while maintaining curve correction.

Spinal instrumentation without fusion for progressive scoliosis in young children

Between 1973 and 1993, a heterogeneous group of 67 children with progressive scoliosis entered a program of incremental-distraction spinal instrumentation without fusion supplemented by full-time external orthotic support. Over the course of treatment, curve magnitude improved from an average of 67 degrees at initial instrumentation to 47 degrees at definitive fusion. For all patients, curve response tended to decline with consecutive procedures. The measured growth of the instrumented but unfused spinal segments averaged 3.1 cm over a mean treatment period of 3.1 years. The results of our study suggest that spinal instrumentation without fusion can control progressive scoliosis in a majority of children while allowing normalized growth of instrumented spinal segments. The mean duration of treatment and ultimate gain in spinal length are constrained by progressive structural changes that alter curve response to incremental distraction. Despite these limitations, spinal instrumentation without fusion may provide a reasonable management alternative when individualized among these difficult patients.

Can c7 plumbline and gravity line predict health related quality of life in adult scoliosis

Study Design. This study prospectively evaluated the health related quality of life (HRQOL) of 73 adults presenting with scoliosis at a single institution, as related to their spinal (C7 plumbline) and global (gravity line) balance. Objective. To assess the influence of sagittal and coronal balance on HRQOL in adult scoliosis. Summary of Background Data. Many surgeons believe that achieving adequate spinal balance is important in the management of adult spinal deformity, but the evidence supporting this concept remains limited. A previous study has found weak correlations between sagittal spinal balance and HRQOL in adult spinal deformity, but this finding has never been confirmed independently. In addition, although the use of the gravity line is gaining interest in the evaluation of global balance, it remains unknown if this parameter is associated with HRQOL. Methods. During a 1-year period, 73 consecutive new patients presenting with unoperated adult scoliosis and requiring full spine standing radiographs were evaluated using a force plate in order to simultaneously assess the gravity line. All patients also completed the Oswestry Disability Index (ODI) questionnaire to assess the HRQOL. Spinal balance was evaluated from the C7 plumbline and global balance from the gravity line, respectively. C7 plumbline and gravity line were both assessed with respect to the posterosuperior corner of the S1 vertebral body and central sacral vertebral line in the sagittal and coronal plane, respectively. C7 plumbline and gravity line, as well as their relative position, were correlated with the ODI, using Spearman coefficients. Results. Sagittal spinal (C7 plumbline) and global (gravity line) balance, as well as their relative position were significantly related to the ODI. A poor ODI (>34) was associated with a sagittal C7 plumbline greater than 6 cm, a sagittal gravity line greater than 6 cm, and a C7 plumbline in front of the gravity line. Correlations between coronal balance and the ODI were not statistically significant. Conclusion. Sagittal spinal and global balance was strongly related to the ODI in adults with scoliosis. The observed correlation coefficients were higher than those reported in the only previous study suggesting the detrimental association of positive sagittal balance on ODI in adult spinal deformity. Coronal spinal and global balance did not influence the ODI in the current study cohort. Thisstudy underlines the relevance of C7 plumbline and gravity line in the evaluation of spinal and global balance, and lends further support to the philosophy of achieving adequate sagittal balance in the management of adult spinal deformity, especially in patients older than 50 years old with degenerative scoliosis.

Post-traumatic kyphosis. A review of forty-eight surgically treated patients.

We reviewed the cases of forty-eight patients who were treated surgically for symptomatic post-traumatic kyphosis of the thoracic or lumbar spine six months or longer after the initial injury. Presenting signs and symptoms included pain in 94 per cent, progression of kyphosis in 46 per cent, instability in 36 per cent, and increasing neural deficit in 27 per cent. Twenty-four patients had had a prior laminectomy. Posterior fusion (sixteen patients) and combined anterior and posterior fusion (twenty patients) always resulted in primary fusion. Anterior fusion alone was attempted in twelve patients, but failed in six. The average final correction of the deformity was 26 per cent. Pain was reduced significantly in 31 per cent of the patients and was relieved completely in 67 per cent. Fourteen of the forty-eight patients also had an anterior decompression, of whom five were neurologically improved, four were unchanged or stabilized, and four were immediately worse after operation. One patient was neurologically stable for twenty-three months postoperatively and then deteriorated again. No patients were neurologically improved following posterolateral decompression or repeat exploratory laminectomy.

Scheuermann's Kyphosis and Roundback Deformity: Results Of Milwaukee Brace Treatment

Review of 223 patients with Scheuermanns kyphosis and postural roundback showed that seventy-five patients with this deformity who had completed Milwaukee brace treatment had their kyphosis improved by an average of 40 per cent; their vertebral wedging, by an average of 41 per cent; and their lordosis, by an average of 36 per cent. Severity of kyphosis (greater than 65 degrees), skeletal maturity (as shown by iliac epiphysis closure), and vertebral wedging averaging more than 10 degrees were factors which limited the amount of correction obtained with the Milwaukee brace. The presence of scoliosis did not affect the end result.

Excessive thoracic lordosis and loss of pulmonary function in patients with idiopathic scoliosis

Idiopathic thoracic lordoscoliosis is more common and more productive of respiratory compromise than is kyphoscoliosis. In some patients with idiopathic scoliosis, thoracic lordosis is the predominant component of the disease. Five such patients, all of whom had idiopathic scoliosis with excessive thoracic lordosis, progressive deformity despite Milwaukee brace treatment, and significant compromise of pulmonary function, are presented. Harrington instrumentation (distraction rod only) and spine fusion improved the deformity and respiratory function. The recommended treatment for this type of idiopathic scoliosis is early recognition and prompt surgical correction. The Milwaukee brace should be avoided. Postoperative management must include early ambulation combined with vigorous breathing exercises.

Neurologic safety in spinal deformity surgery.

Paralysis following surgery to correct spinal deformity can be a catastrophic problem. Surgeons must be aware that there are a multitude of risk factors related to the etiology and pattern of deformity and that there are a multitude of events and actions in the operating room and after the surgery that influence the development of paralysis. Patients and families need to know that although paralysis can occur, it is rare, and that it can occur despite the very best efforts of the surgeon. This is a review of the available literature on the subject and some personal experiences of the author.