Long-term outcomes and complications of isolated anterior thoracolumbar fusion for neuromuscular scoliosis associated with myelomeningocele

PURPOSE

Neuromuscular scoliosis associated with myelomeningocele is a difficult clinical dilemma for the treating surgeon. The traditional surgical treatment consists of a posterior spinal instrumented fusion with or without a combined anterior procedure, but this has been associated with high complication rates, mostly related to deep infection. An anterior thoracolumbar fusion is not able to address the entirety of the deformity in many cases but could potentially avoid the devastating infection risks from the posterior approach by avoiding compromised skin. This study aims to evaluate the long-term outcomes and complications associated with isolated anterior thoracolumbar fusion in this high-risk group.

METHODS

This study is a retrospective analysis of patients with myelomeningocele-associated scoliosis treated with an isolated anterior spinal fusion over a 20-year time period at a single center. Surgical details, demographics, curve characteristics and complications were recorded. Comparisons were made between patients who required revision surgery and those who did not.

RESULTS

Sixteen patients were enrolled with an average age of 12.7 years at the time of surgery and average follow-up of 5.5 years. Patients had on average 7.4 levels fused anteriorly with the most common levels being T10-L4. There were no deep wound infections associated with the anterior surgery. Overall, nine patients (56%) had to be revised posteriorly due to adding-on or junctional deformity at an average of 3.7 years after index procedure. Four patients were revised due to proximal adding-on, while 1 was extended distally. Four additional patients were extended both proximally and distally. Of the posterior revisions, 2 patients developed deep wound infections, and both of these were in patients extended distally. Preoperative lumbar lordosis was higher in patients who required distal extension (100 vs. 69 degrees; p = 0.035).

CONCLUSIONS

Patients undergoing isolated anterior fusion for scoliosis associated with myelomeningocele have low infection rates but often require posterior revision. The majority of patients can avoid the deep infection risk associated with distal posterior surgery at long-term follow-up.

LEVEL OF EVIDENCE

IV.

Vacuum-assisted closure for deep infection after spinal instrumentation for scoliosis

Our aim was to review the efficacy of the wound vacuum-assisted closure (VAC) system in the treatment of deep infection after extensive instrumentation and fusion for spinal deformity in children and adolescents. A total of 14 patients with early deep spinal infection were treated using this technique. Of these, 12 had neuromuscular or syndromic problems. Clinical and laboratory data were reviewed. The mean follow-up was 44 months (24 to 72). All wounds healed. Two patients required plastic surgery to speed up the process. In no patient was the hardware removed and there was no loss of correction or recurrent infection. We believe that the wound VAC system is a useful tool in the armamentarium of the spinal surgeon dealing with patients susceptible to wound infections, especially those with neuromuscular diseases. It allows for the retention of the instrumentation and the maintenance of spinal correction. It is reliable and easy to use.

Rotationplasty in skeletally immature patients. Long-term followup results

Twenty-one skeletally immature patients with a Grade IIB osteosarcoma about the knee were treated with a modified Van Nes rotationplasty. Fourteen patients were followed up for 4 to 10.5 years (mean followup, 8 years). Functional assessment using Enneking's method showed all had good or excellent results. No patient thought that the reconstruction affected their ability to achieve recreational, sporting, or career goals. The reconstruction is durable and is not associated with an increase in late complications.

Lower-limb deficiencies and amputations in children

Important differences exist in the management of child and adult amputees. Many factors, including the etiology of childhood limb deficiencies, expected skeletal growth, functional demand on the locomotor system and prosthesis, appositional bone stump overgrowth, and psychological challenges, make caring for these young patients particularly challenging. Adherence to the general principles of childhood amputation surgery will typically guide one to the optimal functional result. These principles can be summarized as follows: (1) Preserve length. (2) Preserve important growth plates. (3) Perform disarticulation rather than transosseous amputation whenever possible. (4) Preserve the knee joint whenever possible. (5) Stabilize and normalize the proximal portion of the limb. (6) Be prepared to deal with issues in addition to limb deficiency in children with other clinically important conditions. A large proportion of young amputees undergo a Syme disarticulation, modified Boyd amputation, or knee disarticulation. A modified Van Nes rotationplasty procedure is also useful in this age group. All these provide the child with a weight-bearing stump with good growth potential and no complications due to bone overgrowth. Appropriate timing of amputation procedures and prosthetic fittings is essential to maximize functional benefit to the patient.

Latex allergy in non-spina bifida patients: unfamiliar intra-operative anaphylaxis

BACKGROUND

The medical literature has described the prevalence of latex allergy in the spina bifida population and its implications for surgical intervention. We report three cases of severe and unexpected intra-operative anaphylaxis secondary to latex exposure in non-spina bifida patients.

METHODS

A retrospective review of case notes identified three non-spina bifida patients who suffered intra-operative anaphylaxis due to latex allergy. Personal and telephone interview and patient chart review was performed to detail a past history of multiple latex exposure, atopy, the anaphylaxis event and the postoperative outcome.

RESULTS

Three non-spina bifida patients are described. One suffered a cardiopulmonary arrest, the remaining two patients had severe vascular hypotension and airway resistance that was only relieved after administration of vasoconstrictors and bronchodilators. Postoperatively, all three tested strongly positive to latex allergen testing. Each patient had a history of multiple surgical latex exposure and specific allergies or allergic-type symptoms pre-operatively.

CONCLUSION

We believe that the predictors of a severe allergic reaction to latex with surgical exposure in non-spina bifida patients may be similar to those predictors known in the spina bifida population. Identification of such at-risk patients will reduce the risk of significant intra-operative morbidity and possible mortality by the introduction of a latex-free operating environment.

Proximal femoral focal deficiency: results of rotationplasty and Syme amputation

We reviewed the results of treatment of sixteen patients who had had an isolated unilateral proximal femoral focal deficiency; nine were managed with a rotationplasty and seven, with a Syme amputation combined with an arthrodesis of the knee. We evaluated the perceived physical appearance, gross motor function, and metabolic energy expended in walking. The mean duration of follow-up was 9.9 years (range, four to fourteen years). The mean age of the patients at the time of the study was 13.9 years (range, eight to 18.4 years) in the rotationplasty group and 14.8 years (range, 9.5 to 19.9 years) in the Syme-amputation group. There were three female patients in each group. Roentgenograms showed that the femoral head was in the acetabulum (Aitken class A or B) in four of the seven patients in the Syme-amputation group and in five of the nine patients in the rotationplasty group; the remaining patients did not have this finding (Aitken class C or D). There was no difference in gross motor function or perceived physical appearance between the groups. Rotationplasty was associated with a more energy-efficient gait (mean, 0.153 milliliter of oxygen per kilogram-meter [range, 0.128 to 0.173 milliliter of oxygen per kilogram-meter] than was Syme amputation (mean, 0.169 milliliter of oxygen per kilogram-meter [range, 0.151 to 0.182 milliliter of oxygen per kilogram-meter]). Both types of treatment resulted in a net oxygen utilization per distance (efficiency) that was less than the values reported after amputations performed for non-congenital disorders.

Massive allografts in the treatment of osteosarcoma and Ewing sarcoma in children and adolescents

A retrospective review was performed of the results of all allograft reconstructions that had been done after the resection of an osteosarcoma or an Ewing sarcoma in a skeletally immature patient between 1982 and 1989 at The Hospital for Sick Children in Toronto. There were twenty-six patients. Six reconstructions were intercalary, sixteen were resection arthrodeses, three followed resection of a bone segment including the epiphysis (osteoarticular reconstruction), and one was a replacement of the entire humerus. Resection arthrodesis about the knee was performed with a smooth intramedullary rod and with one growth plate left intact. Six procedures were performed in the upper extremity. Excluding the patients who died, the average duration of follow-up was five years and three months. Twenty-one of the twenty-six patients had reached skeletal maturity at the time of follow-up. Eighteen (69 per cent) of the patients had a good or excellent result, four (15 per cent) had a fair result, and four had a failure. Twenty patients (77 per cent) had at least one complication (other than a limb-length discrepancy), and fourteen (54 per cent) sustained at least one fracture of the allograft. Fifteen patients who had had a reconstruction in the lower extremity had survived with survival of the allograft at the time of the latest follow-up. A limb-length discrepancy of at least two centimeters developed in nine of the fifteen patients. Five were managed with a contralateral epiphyseodesis, and one of them had an unsuccessful attempt at limb-lengthening as well. The patients who had a limb-length discrepancy of more than three centimeters at the time of follow-up had been significantly younger (p < 0.05) at the time of the reconstruction than those who had a smaller discrepancy. Three allografts (12 per cent), two of which were implanted early in the series, became infected. Soft-tissue coverage is of paramount importance for the prevention of infection, and we now routinely perform primary muscle (gastrocnemius or latissimus dorsi) transfers when dealing with an inadequate muscle envelope. Twelve patients were followed for more than four years (average, six years and seven months); they had no complications other than increased limb-length discrepancy and one subluxation of the shoulder after the first four years following the reconstruction. Although the rate of complications is higher than in adults, allograft reconstruction remains a useful option for the management of skeletally immature individuals.(ABSTRACT TRUNCATED AT 400 WORDS)

Use of bone scan in management of patients with peripheral gangrene due to fulminant meningococcemia

Technetium bone scintigraphy was performed in four patients with fulminant meningococcemia and extensive peripheral gangrene. The bone scans showed variable levels of absent uptake in all extremities of the four patients who subsequently required quadrimembral amputations. In 13 limbs, the level of amputation was determined primarily by the bone scan findings, and operation was successful in 84% of those limbs. These findings suggest that bone scanning is a useful adjunct in differentiating viable from nonviable tissues in patients with extensive peripheral gangrene secondary to fulminant meningococcemia and thus helps determine the appropriate level of amputation in such patients.

Modified Van Nes rotationplasty in the treatment of malignant neoplasms in the lower extremities of children

A technique of modified Van Nes rotationplasty has been used since 1981 for limb salvage surgery in children and adolescents with malignant sarcoma of the lower extremity. The original procedure for lesions of the distal femur was further modified and adopted for selected lesions of the proximal femur and tibia. Sixteen skeletally immature children form the base of this report. The tumors were located in the distal femur in ten children, the proximal tibia in five and the proximal femur in one. There were no intraoperative complications and postoperative complications included one infection requiring debridement and three minor healing delays. There were no local recurrences, neurovascular compromises, late derotations, or psychologic decompensations. One patient died of metastatic disease and another died of a second malignancy (leukemia). The remaining patients are good, functional, below-knee prosthesis users who participate in a number of sporting and athletic activities. The procedure is safe, has a relatively low complication rate, allows for the functional demands of an active, growing child, and accommodates for the future growth of extremities.

Modified Van Nes rotationplasty for osteosarcoma of the proximal tibia in children

Above-knee amputation has been the traditional treatment for osteosarcoma of the proximal tibia. Recent advances in chemotherapy have encouraged the development of limb-salvage techniques. Van Nes rotationplasty for malignant lesions of the distal femur has increased in popularity as a reconstructive technique, but no similar procedure has been described for lesions of the proximal tibia. We have developed a modified rotationplasty for this lesion and have performed it in four children. The surgical technique, postoperative management and results of the procedure are described. Two patients had delayed wound healing. No other complications have developed and our patients were disease-free at follow-up, while the appearance of the leg was well accepted by the patients and their parents. This procedure is a useful addition to the armamentarium of the tumour surgeon for the treatment of malignant lesions of the proximal tibia.

Congenital pseudarthrosis of the tibia: treatment with free vascularized fibular grafts

We used free vascularized fibula transfers to treat 12 patients with congenital pseudarthrosis of the tibia. The mean age at surgery was 6.5 years, and the average follow-up was 3.4 years. Only one patient had persistent nonunion at the time of last follow-up, but he had 2.2 operations after the initial vascularized procedure. Problems included delayed union at the distal anastomosis and refracture. Union can be achieved in most patients, but attention to technical detail is very important. All angulation must be corrected and, at the first sign of delayed union, the site should be regrafted and intramedullary fixation should be used.

Amputation stump lengthening with the Ilizarov technique. A case report

It is often difficult to create a functional stump from a traumatic amputation, especially in a child. A case is described of a traumatic, high, below-knee amputation in a five-year-old child. The resulting stump was too short to allow a conventional below-knee prosthesis, decreasing gait efficiency. The Ilizarov technique was used to increase tibial length. Bony lengthening was very successful, but several problems were encountered with the soft-tissue reconstruction. This technique of stump reconstruction holds promise only if the soft-tissue problems are anticipated. The suggestions for future stump-lengthening procedures are preparatory plastic surgery for skin requirements including infection prevention measures.

Van Nes rotationplasty with segmental limb resection

Segmental limb resection is becoming a practical alternative to limb ablation in tumor surgery. The addition of Van Nes rotationplasty to provide a pseudo knee joint has been found to be a practical, functional addition facilitating prosthesis use. This procedure has now been used successfully in 21 children with malignant neoplasms, with few complications. The surgical technique, as outlined, produces significantly improved functional results over an above-knee amputation or hip disarticulation.

Comparative assessment of gait after limb-salvage procedures

We performed metabolic studies of gait in eighteen patients who had had above-the-knee amputation, block resection and arthrodesis of the knee, or block resection and rotationplasty for a malignant tumor of the distal end of the femur or the proximal end of the tibia. According to the measurement of consumption of oxygen, the patients who had had rotationplasty walked most efficiently. Those who had had arthrodesis used more oxygen and walked at a slower rate.

Orthopaedic complications of lumboperitoneal shunts

Lumboperitoneal (LP) shunts performed for communicating hydrocephalus have been reported to lead to neurologic deficits in the lower limbs and spinal deformities as a result of arachnoiditis. A chart review of 375 children who underwent LP shunts between 1960 and 1981 at The Hospital For Sick Children in Toronto was undertaken. Of the 375 charts reviewed, evidence of shunt-induced neurologic deficits was seen in 63 patients. Thirty-four patients had back pain with or without sciatica, 45 patients had hamstring tightness, and 40 patients had foot deformities. Forty-nine patients had lumbar hyperlordosis, lordoscoliosis, and scoliosis. These deformities are postulated to be the result of arachnoiditis involving the conus medullaris and lower lumbar roots.

Management of displaced extension-type supracondylar fractures of the humerus in children

The cases of 230 patients who had a displaced extension-type supracondylar fracture of the humerus were reviewed retrospectively. The results of treatment by four different methods were assessed clinically and compared. The mean length of follow-up was 4.6 years (range, one to nine years). The highest percentages of excellent results were achieved by percutaneous Kirschner-wire fixation (78 per cent), skeletal traction (67 per cent), and open reduction with internal fixation (67 per cent). Closed reduction and application of a cast was associated with a significantly lower percentage of early and late complications, including Volkmann ischemic contracture and cubitus varus. It is recommended that treatment with a cast be reserved for undisplaced fractures only. Percutaneous Kirschner-wire fixation is advocated as the method of choice for the majority of displaced fractures.

Mesenchymal chondrosarcoma: a report of 17 cases

Mesenchymal chondrosarcoma is a rare, almost uniformally lethal variant of chondrosarcoma which has been regarded as resistant to chemotherapy and radiotherapy. Seventeen cases are reported; 14 are dead of tumor or still alive with disease; eight of the 14 died less than one year after treatment, predominately of distant metastatic disease. This confirms previous reports of the highly aggressive nature of mesenchymal chondrosarcoma. Although surgery is regarded as the major method of treating the primary disease, it has limitations because many tumors cannot be adequately removed owing to location or extension to unresectable sites. It was found that such tumors respond to irradiation and that a combination of chemotherapy and radiotherapy should be used in unresectable tumors or those resected with inadequate margins. Adjuvant chemotherapy is advised in all cases treated with radical surgical excision. Unfavorable prognostic factors in mesenchymal chondrosarcoma are pain as a presenting symptom and a central rather than a peripheral limb location.

Radiotherapy of chondrosarcoma of bone

A retrospective analysis of 31 cases of chondrosarcoma of bone treated by radiotherapy at the Princess Margaret Hospital between 1958 and 1976 is presented. In comparison with other large series, our group of patients were found to have been unfavourably selected with respect to the known prognostic factors: histology (39% mesenchymal and dedifferentiated), site (75% arising in the trunk and head and neck), adequacy of operative treatment (none having had a complete surgical excision), and presenting symptoms (two-thirds presenting with pain). Twelve patients with primary (good, moderate, and unknown differentiation) chondrosarcoma were radically irradiated; 6 of these 12 have been alive and well without tumor for periods ranging from three and half to 16 years and 3 of these are alive and well for 15 years or more following radiotherapy. The other 6 patients responded or disease stabilized following radiotherapy for periods ranging from 16 months to eight years. One poorly differentiated tumor was radically irradiated and did not respond. Eleven patients were irradiated palliatively (5 dedifferentiated and mesenchymal, 4 secondary, and 2 primary chondrosarcomas), generally with low doses of irradiation, and only 4 responded transiently for periods ranging from three to 12 months. Seven patients with mesenchymal and dedifferentiated tumors were radically irradiated. Four responded or disease stabilized, and 1 of these patients was alive and well at 3 years; 3 did not respond. Six died with distant metastasis. It is concluded that chondrosarcoma of bone is a radioresponsive tumor and the place of radiotherapy in the treatment of this disease and the reason for its being labelled a radioresistant tumor are discussed. The problems of assessing response of chondrosarcoma to therapy are also discussed. It is suggested that chemotherapy may have a role in the management of mesenchymal and dedifferentiated chondrosarcoma.