The effect of spine fusion on respiratory function in Duchenne muscular dystrophy

Surgical and long-term functional outcomes of patients with Duchenne muscular dystrophy following spinal deformity correction

BACKGROUND

Life expectancy in patients with Duchenne muscular dystrophy (DMD) has improved due to advances in medical care. DMD patients develop progressive spinal deformity after loss of ambulatory function and onset of wheelchair dependence for mobility. There is limited published data on the effect of spinal deformity correction on long-term functional outcomes, quality of life (QoL), and satisfaction in DMD patients.

AIM

To investigate the long-term functional outcomes following spinal deformity correction in DMD patients.

METHODS

This was a retrospective cohort study from 2000-2022. Data was collected from hospital records and radiographs. At follow-up, patients completed the muscular dystrophy spine questionnaire (MDSQ). Statistical analysis was performed by linear regression analysis and ANOVA to analyse clinical and radiographic factors significantly associated with MDSQ scores.

RESULTS

Forty-three patients were included with mean age 14.4 years at surgery. Spino-pelvic fusion was performed in 41.9% of patients. Mean surgical time was 352.1 min and mean blood loss was 36% of estimated total blood volume. Mean hospital stay was 14.1 d. Postoperative complications occurred in 25.6% of patients. Mean preoperative scoliosis was 58°, pelvic obliquity 16.4°, thoracic kyphosis 55.8°, lumbar lordosis 11.1°, coronal balance 3.8 cm, and sagittal balance + 6.1 cm. Mean surgical correction of scoliosis was 79.2% and of pelvic obliquity was 80.8%. Mean follow-up was 10.9 years (range: 2-22.5). Twenty-four patients had died at follow-up. Sixteen patients completed the MDSQ at mean age 25.4 years (range 15.2-37.3). Two patients were bed-ridden and 7 were on ventilatory support. Mean MDSQ total score was 38.1. All 16 patients were satisfied with the results of spinal surgery and would choose surgery again if offered. Most patients (87.5%) reported no severe back pain at follow-up. Factors significantly associated with functional outcomes (MDSQ total score) included greater duration of post-operative follow-up, age, scoliosis postoperatively, correction of scoliosis, increased lumbar lordosis postoperatively, and greater age at loss of independent ambulation.

CONCLUSION

Spinal deformity correction in DMD patients leads to positive long-term effects on QoL and high patient satisfaction. These results support spinal deformity correction to improve long-term QoL in DMD patients.

Comparison of survival analysis between surgical and non-surgical treatments in Duchenne muscular dystrophy scoliosis

BACKGROUND CONTEXT

There are still controversies about the effects of spinal surgeries for Duchenne muscular dystrophy (DMD) scoliosis on functional outcome, respiratory function, and the survival rate.

PURPOSE

The purpose of this retrospective investigation was to compare the clinical course over time between the patients who were treated surgically and those who were treated nonsurgically. Through this comparison, we tried to determine how surgical treatment could affect the functional status, pulmonary function, and survival rate in patients with DMD scoliosis.

STUDY DESIGN/SETTING

Single-center retrospective cohort study.

PATIENT SAMPLE

We reviewed the clinical data of 199 male patients with DMD scoliosis who were followed up at our center for an average of 6.4 years between 2003 and 2017.

OUTCOME MEASURES

The basic radiologic parameters evaluated include the Cobb angle and pelvic obliquity on a whole spine X-ray. Further, the Swinyard scale for functional status, forced vital capacity (FVC) for respiratory function, and mortality were compared between the surgical group and nonsurgical group.

METHODS

The radiologic parameters and Swinyard scale stage were compared between the surgical group and nonsurgical group at baseline and 2, 5, and 10 years. For the FVC, serial changes every year were investigated in both groups. Mortality was surveyed between the surgical group and nonsurgical group.

RESULTS

Of the 199 patients, 99 patients underwent the instrumented spinal fusion surgery and 100 patients in the nonsurgical group opted for conservative management. Radiologic results of the two groups were not different at baseline, but during the follow-up periods, the surgical group demonstrated better Cobb angles and pelvic obliquities. The surgical group showed a better functional status than did the nonsurgical group (6.7±0.9 versus [vs.] 7.2±0.7, p<.001). These functional differences between the groups were continuously observed during the follow-up period. Similarly, the FVC at baseline was higher in the surgical group than in the nonsurgical group (1005.7±421.4 mL vs. 787.3±574.1 mL, p=.005). Although FVC in the nonsurgical group consistently decreased during the follow-up (4.8% decrease/year), FVC in the surgical group increased up to the 2-year follow-up period compared with the baseline value and decreased during the follow-up period (2.8% decrease/year). Mortality was higher in the nonsurgical group than in the surgical group (n=22/100, 22.0% vs. n=8/99, 8.1%; p<.001) during an average follow-up duration of 6.4 years. Mean survival was longer in the surgical group than in the nonsurgical group (12.2 years vs. 8.3 years, hazard ratio=2.43, p=.02).

CONCLUSIONS

Spinal surgery for DMD scoliosis improved the FVC for approximately 2 years postoperatively compared to non-surgical treatment. The surgical group had a better functional status and FVC at baseline than the non-surgical group. The positive effect of surgical treatment on the FVC is owing to scoliosis correction, which delayed the decrease of FVC and consequently extended the survival rate of the patients with DMD scoliosis.

Perioperative Evaluation of Respiratory Muscle Strength after Scoliosis Correction in Patients with Duchenne Muscular Dystrophy

Study Design

Retrospective cohort study.

Purpose

To investigate the effect of spinal correction on respiratory muscle strength in patients with Duchenne muscular dystrophy (DMD).

Overview of Literature

Several studies have reported that scoliosis correction in patients with DMD does not improve pulmonary function. In these studies, pulmonary function was evaluated using the traditional spirometric values of percent vital capacity (%VC) and percent forced vital capacity (%FVC). However, traditional spirometry may not be suitable for patients with DMD because the results can be influenced by patient fatigue or level of understanding. Therefore, we evaluated respiratory function focusing on respiratory muscle strength using maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP), in addition to %VC and %FVC.

Methods

We retrospectively reviewed 16 patients with DMD who underwent spinal correction surgery between 2006 and 2011 at Kitasato University Hospital. All patients were males, and the mean age was 13.5 years. Respiratory muscle strength was evaluated using MIP, MEP, and SNIP. Measurements were obtained preoperatively and at 1 and 6 months postoperatively, and %VC and %FVC were obtained preoperatively and within 6 months postoperatively.

Results

The mean preoperative and postoperative %VC values were 54.0% and 51.7%, whereas the mean %FVC values were 53.9% and 53.2%, respectively. The mean MIP, MEP, and SNIP values obtained preoperatively and at 1 and 6 months postoperatively were as follows: MIP, 40.5, 42.7 and 47.2 cm H₂O; MEP, 26.0, 28.0, and 29.0 cm H₂O; and SNIP, 33.4, 33.0, and 33.0 cm H₂O; respectively. The mean MIP and MEP values significantly improved postoperatively. There were no significant differences in SNIP, %VC, or %FVC preand postoperatively.

Conclusions

By focusing on respiratory muscle strength, our results suggest that scoliosis correction in patients with DMD might have a favorable effect on respiratory function.

Factors influencing the evaluation and management of neuromuscular scoliosis: A review of the literature

Neuromuscular scoliosis (NMS) is the second most prevalent spinal deformity (after idiopathic scoliosis) and is usually first identified during early childhood. Cerebral palsy (CP) is the most common cause of NMS, followed by Duchenne muscular dystrophy (DMD). Progressive spinal deformity causes difficulty with daily care, walking and sitting, and can lead to back and rib pain, cardiac and pulmonary complications, altered seizure thresholds, and skin compromise. Early referral to specialist spinal services and early diagnosis of NMS is essential to ensure appropriate multidisciplinary patient management. The most important goals for patients are preservation of function, facilitation of daily care, and alleviation of pain. Non-operative management includes observation or bracing for less severe and flexible deformity in young patients as a temporising measure to provide postural support. Surgical correction and stabilisation of NMS is considered for patients with a deformity >40-50°, but may be performed for less severe deformity in patients with DMD. Post-operative intensive care, early mobilisation and nutritional supplementation aim to minimise the rate of post-surgical complications, which are relatively common in this patient group. However, surgical management of NMS is associated with good long-term outcomes and high satisfaction rates for patients, their relatives and carers.

Long-term Follow-up of Pulmonary Function and Scoliosis in Patients With Duchenne's Muscular Dystrophy and Spinal Muscular Atrophy

BACKGROUND

Spine surgery for neuromuscular scoliosis in patients with Duchenne's Muscular Dystrophy (DMD) and Spinal Muscular Atrophy (SMA) remained controversial. This study aimed to review the long-term results of spine surgery and its effect on pulmonary function in these patients.

METHODS

A retrospective review was conducted for the above patients who had undergone surgery from 1990 to 2006 in a tertiary hospital. Their yearly lung function tests, clinical records, and x-ray films before and after surgery were reviewed. All patients had at least 2 lung function tests performed before surgery and at least 3 lung function tests performed after surgery. Records of perioperative pulmonary infections that resulted in hospital admissions were also retrieved from the hospital computer system.

RESULTS

Forty patients were reviewed: 29 with DMD, 11 with SMA. The mean follow-up period was 11.6 years. For patients with DMD, the mean correction of Cobb's angle from surgery was 34.1 degrees. The rate of decline of the predicted forced vital capacity preoperatively was 7.80% per year, and was reduced to 4.26% per year postoperatively (P<0.001). For patients with SMA, the mean correction of Cobb's angle from surgery was 44.1 degrees. The rate of decline of the predicted forced vital capacity preoperatively was 5.31% per year, and was reduced to 1.77% per year postoperatively (P<0.001). For both DMD and SMA patients, the difference between the rate of preoperative and postoperative pulmonary infections that resulted in hospital admission were, however, not significant (P=0.433 and 0.452, respectively).

CONCLUSIONS

Scoliosis surgery in patients with DMD and SMA results in a long-term decreased rate of decline in pulmonary function over a follow-up period of more than 10 years. The level of the apical vertebrae of the scoliosis did not demonstrate a significant trend on the pulmonary function. The frequency of chest infections did not improve by scoliosis surgery.

LEVEL OF SIGNIFICANCE

Level III—Retrospective study.

Surgery for scoliosis in Duchenne muscular dystrophy

BACKGROUND

Scoliosis in patients with Duchenne muscular dystrophy (DMD) is usually progressive and is treated with surgery. However, it is unclear whether the existing evidence is sufficiently scientifically rigorous to support a recommendation for spinal surgery for most patients with DMD and scoliosis. This is an updated review, and an updated search was undertaken in which no new studies were found for inclusion.

OBJECTIVES

To determine the effectiveness and safety of spinal surgery in patients with DMD with scoliosis. We intended to test whether spinal surgery is effective in increasing survival and improving respiratory function, quality of life, and overall functioning, and whether spinal surgery is associated with severe adverse effects.

SEARCH METHODS

On 16 June 2015 we searched the Cochrane Neuromuscular Disease Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and CINAHL Plus. We also searched ProQuest Dissertation and Thesis database (January 1980 to June 2015), the National Institutes of Health Clinical Trials Database (6 January 2015), and the WHO International Clinical Trials Registry Platform (17 June 2015), and checked references. We imposed no language restrictions.

SELECTION CRITERIA

We planned to include controlled clinical trials using random or quasi-random allocation of treatment evaluating all forms of spinal surgery for scoliosis in patients with DMD in the review. The control interventions would have been no treatment, non-operative treatment, or a different form of spinal surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration. Two review authors independently examined the search results and evaluated the study characteristics against inclusion criteria in order to decide which studies to include in the review.

MAIN RESULTS

Of the 49 relevant studies we found, none met the inclusion criteria for the review because they were not clinical trials, but prospective or retrospective reviews of case series.

AUTHORS' CONCLUSIONS

Since no randomized controlled clinical trials were available to evaluate the effectiveness of scoliosis surgery in patients with DMD, we can make no good evidence-based conclusion to guide clinical practice. Patients with scoliosis should be informed as to the uncertainty of benefits and potential risks of surgery for scoliosis. Randomized controlled trials are needed to investigate the effectiveness of scoliosis surgery, in terms of quality of life, functional status, respiratory function, and life expectancy.

Assessment and management of respiratory function in patients with Duchenne muscular dystrophy: current and emerging options

Duchenne muscular dystrophy (DMD) is an X-linked myopathy resulting in progressive weakness and wasting of all the striated muscles including the respiratory muscles. The consequences are loss of ambulation before teen ages, cardiac involvement and breathing difficulties, the main cause of death. A cure for DMD is not currently available. In the last decades the survival of patients with DMD has improved because the natural history of the disease can be changed thanks to a more comprehensive therapeutic approach. This comprises interventions targeted to the manifestations and complications of the disease, particularly in the respiratory care. These include: 1) pharmacological intervention, namely corticosteroids and idebenone that significantly reduce the decline of spirometric parameters; 2) rehabilitative intervention, namely lung volume recruitment techniques that help prevent atelectasis and slows the rate of decline of pulmonary function; 3) scoliosis treatment, namely steroid therapy that is used to reduce muscle inflammation/degeneration and prolong ambulation in order to delay the onset of scoliosis, being an additional contribution to the restrictive lung pattern; 4) cough assisted devices that improve airway clearance thus reducing the risk of pulmonary infections; and 5) non-invasive mechanical ventilation that is essential to treat nocturnal hypoventilation, sleep disordered breathing, and ultimately respiratory failure. Without any intervention death occurs within the first 2 decades, however, thanks to this multidisciplinary therapeutic approach life expectancy of a newborn with DMD nowadays can be significantly prolonged up to his fourth decade. This review is aimed at providing state-of-the-art methods and techniques for the assessment and management of respiratory function in DMD patients.

Surgery for scoliosis in Duchenne muscular dystrophy

BACKGROUND

Scoliosis in people with Duchenne muscular dystrophy is usually progressive and treated with surgery. However, it is unclear whether the existing evidence is sufficiently scientifically rigorous to support a recommendation for spinal surgery for most people with Duchenne muscular dystrophy and scoliosis. This is an updated review and an updated search was undertaken in which no new studies were found.

OBJECTIVES

To determine the effectiveness and safety of spinal surgery in people with Duchenne muscular dystrophy with scoliosis. We intended to test whether spinal surgery is effective in increasing survival, improving respiratory function, improving quality of life and overall functioning; and whether spinal surgery is associated with severe adverse effects.

SEARCH METHODS

We searched the specialized registers of the Cochrane Neuromuscular Disease Group (31 July 2012), MEDLINE (January 1966 to July 2012), EMBASE (January 1947 to July 2012), CENTRAL (2012, Issue 7 in the Cochrane Library), CINAHL Plus(January 1937 to July 2012), Proquest Dissertation and Thesis Database (January 1980 to July 2012), and the National Institute of Health Clinical Trials Database (July 2012). No language restrictions were imposed.

SELECTION CRITERIA

We planned to include controlled clinical trials using random or quasi-random allocation of treatment evaluating all forms of spinal surgery for scoliosis in people with Duchenne muscular dystrophy in the review. The control interventions would have been no treatment, non-operative treatment, or a different form of spinal surgery.

DATA COLLECTION AND ANALYSIS

Two authors independently examined the search results and evaluated the study characteristics against inclusion criteria to decide which ones would be included in the review.

MAIN RESULTS

On searching, 47 studies were relevant but none met the inclusion criteria for the review, because they were not clinical trials but prospective or retrospective reviews of case series.

AUTHORS' CONCLUSIONS

Since there were no randomized controlled clinical trials available to evaluate the effectiveness of scoliosis surgery in people with Duchenne muscular dystrophy, no evidence-based recommendation can be made for clinical practice. People with scoliosis should be informed about the uncertainty of benefits and potential risks of surgery for scoliosis. Randomized controlled trials are needed to investigate the effectiveness of scoliosis surgery, in terms of quality of life, functional status, respiratory function and life expectancy.

The effect of posterior spinal fusion on respiratory function in Duchenne muscular dystrophy

PURPOSE

Posterior instrumented spinal fusion is indicated for progressive scoliosis that develops in Duchenne muscular dystrophy (DMD) patients. Whilst spinal fusion is known to improve quality of life, there is inconsistency amongst the literature regarding its specific effect on respiratory function. Our objective was to determine the effect of scoliosis correction by posterior spinal fusion on respiratory function in a large cohort of patients with DMD. Patients with DMD undergoing posterior spinal fusion were compared to patients with DMD not undergoing surgical intervention.

METHODS

An observational study of 65 patients with DMD associated scoliosis, born between 1961 and 2001: 28 of which underwent correction of scoliosis via posterior spinal fusion (Surgical Group) and 37 of which did not undergo surgical intervention (Non-Surgical Group). Pulmonary function was assessed using traditional spirometry. Comparisons were made between groups at set times, and by way of rates of change over time.

RESULTS

There was no correlation between the level of respiratory dysfunction and the severity of scoliosis (as measured by Cobb angle) for the whole cohort. The Surgical Group had significantly worse respiratory function at a comparable age pre-operatively compared to the Non-Surgical Group, as measured by per cent predicted forced vital capacity (p = 0.02) on spirometry. The rate of decline of forced vital capacity and per cent predicted forced vital capacity was not slowed following surgery compared to the non-operated cases. There was no significant difference in survival between the two groups.

CONCLUSIONS

Severity of scoliosis was not a key determinant of respiratory dysfunction. Posterior spinal fusion did not reduce the rate of respiratory function decline. These two points suggest that intrinsic respiratory muscle weakness is the main determinant of decline in respiratory function in DMD.

Influência da adequação postural em cadeira de rodas na função respiratória de pacientes com distrofia muscular de Duchenne

O objetivo deste estudo foi avaliar a influência da adequação postural em cadeira de rodas na função respiratória de pacientes com distrofia muscular de Duchenne (DMD). Participaram 12 pacientes com diagnóstico de DMD e que possuíam cadeira de rodas adaptada com idade variando de 10 a 22 anos. Cada indivíduo foi avaliado na própria cadeira de rodas e em uma cadeira de rodas padrão, ou seja, sem reclinação ou tilt. As cadeiras dos participantes possuíam adaptações no encosto e no assento, confeccionados de acordo com as especificidades de cada paciente. A avaliação consistiu em mensurar o volume minuto (VM), volume corrente (VC), capacidade vital forçada (CVF), pressões inspiratória (PImax) e expiratória (PEmax) máximas e pico de fluxo expiratório (PFE). Para análise dos dados, foi utilizado o teste t pareado, adotando-se o nível de significância de 0,05. As adaptações resultaram em melhores valores estatisticamente significativos de todos os parâmetros respiratórios: VM (8.963,3 e 10.762,5 mL/min; p=0,028), VC (319,1 e 433,6 mL; p=0,005), CVF (1.476,3 e 1.850 mL; p=0,005), PImax (-41,2 e -51,2 cmH2O; p=0,022), PEmax (29,6 e 36,7 cmH2O; p=0,004) e PFE (162,1 e 185 L/min; p=0,018). Nossos resultados sugerem que a adequação postural em cadeira de rodas influenciou positivamente a função respiratória de pacientes com DMD.

Pediatric scoliosis

Pediatric scoliosis is a relatively uncommon condition typically first noticed due to altered stature or by routine spine screenings by a school nurse or pediatrician. The formal diagnosis is made with spine radiographs, with coronal curvature measurement of 10° or greater. Treatment may consist of serial observation, bracing until skeletal maturity, or surgery for correction and fusion/stabilization of severe or progressive deformity. Overall success for non-operative management of scoliosis is affected by the etiology for the deformity, close follow up and monitoring for evolution of the deformity, and patient compliance with their treatment regimen. The most common surgical technique is a posterior approach spine fusion with implanted instrumentation, and patients are typically back to their activities of daily living by 6 months postoperatively. Continued intermittent monitoring of the scoliosis throughout adulthood is recommended, to detect late deformity progression, development of arthritis symptoms, or other associated issues.

The natural history of cardiac and pulmonary function decline in patients with duchenne muscular dystrophy

STUDY DESIGN

Retrospective review of scoliosis progression, pulmonary and cardiac function in a series of patients with Duchenne Muscular Dystrophy (DMD).

OBJECTIVE

To determine whether operative treatment of scoliosis decreases the rate of pulmonary function loss in patients with DMD.

SUMMARY OF BACKGROUND DATA

It is generally accepted that surgical intervention should be undertaken in DMD scoliosis once curve sizes reach 35° to allow intervention before critical respiratory decline has occurred. There are conflicting reports, however, regarding the effect of scoliosis stabilization on the rate of pulmonary function decline when compared to nonoperative cohorts.

METHODS

We reviewed spinal radiographs, echocardiograms, and spirometry, hospital, and operative records of all patients seen at our tertiary referral center from July 1, 1992 to June 1, 2007. Data were recorded to Microsoft Excel (Microsoft, Redmond, WA) and analyzed with SAS (SAS Institute, Cary, NC) and R statistical processing software (www.r-project.org).

RESULTS

The percent predicted forced vital capacity (PPFVC) decreased 5% per year before operation. The mean PPFVC was 54% (SD = 21%) before operation with a mean postoperative PPFVC of 43% (SD = 14%). Surgical treatment was associated with a 12% decline in PPFVC independent of other treatment variables. PPFVC after operation declined at a rate of 1% per year and while this rate was lower, it was not significantly different than the rate of decline present before operation (P = 0.18). Cardiac function as measured by left ventricular fractional shortening declined at a rate of 1% per year with most individuals exhibiting a left ventricular fractional shortening rate of more than 30 before operation.

CONCLUSION

Operative treatment of scoliosis in DMD using the Luque Galveston method was associated with a reduction of forced vital capacity related to operation. The rate of pulmonary function decline after operation was not significantly reduced when compared with the rate of preoperative forced vital capacity decline.

Surgical correction of spinal deformity in patients with congenital muscular dystrophy

BACKGROUND

Congenital muscular dystrophy (CMD), among the myopathic disorders is one form of flaccid neuromuscular disorder (NMD). Patients with NMD frequently develop progressive spinal deformity. For NMD patients who have a severe spinal deformity, sitting is often difficult and is accompanied by pain and breakdown of the skin. Spinal deformity surgery in these patients has been highly effective in stabilizing the spine, maintaining upright, comfortable sitting balance, and improving patients' quality of life. However, many studies have reported significant rates of peri/postoperative complications in these patients. To our knowledge, there has been no study on the results of spinal deformity surgery in patients with CMD. The purpose of this study was to review the clinical and radiological results of spinal deformity surgery in this group of patients with CMD.

METHODS

Between 2004 and 2007, a total of 10 CMD patients underwent scoliosis surgery. There were three patients with Fukuyama CMD, three with Ullrich CMD, and 4 with nonsyndromic CMD (merosin-negative). They were nonambulatory. All the patients had standard posterior spinal fusion and pedicle-screw-alone fixation from T3 or T4 to L5 for spinal deformity. Our inclusion criteria required that each patient (1) had considerable difficulty with sitting balance and pain or breakdown of the skin due to scoliosis; (2) was able to ventilate his or her lung autonomously; (3) was not ventilator-dependent; and (4) did not have cardiac failure. Sufficient informed consent was important, and the decision to perform surgery was made by the patient/family with sufficient preoperative informed consent. Patients were trained with inspiratory muscle training (IMT) using an inspiratory muscle trainer (Threshold IMT) for 6 weeks prior to surgery Cardiac function was assessed preoperatively. Pulmonary function tests were performed preoperatively and postoperatively. Radiographic assessments were performed on sitting anteroposterior (AP) and lateral radiographs. These assessments were made periodically. The Cobb angles of the curves and spinal pelvic obliquity (SPO) on the coronal plane, thoracic kyphosis, and lumbar lordosis were measured. The preoperative AP radiograph and side-bending films were examined to determine flexibility. Patients' and parents' satisfaction were surveyed by a self-completed questionnaire at the last follow-up.

RESULTS

Percent forced vital capacity (%FVC) increased from a mean of 30% before IMT to a mean of 34% the day before surgery. The preoperative scoliosis was 75 degrees (range 61 degrees -95 degrees ). The scoliotic curvature on preoperative side-bending films was 19 degrees (range 11 degrees -28 degrees ). All patients were extubated on the day of surgery. No patients developed cardiac or respiratory complications. The scoliotic curvature was 18 degrees (range 10 degrees -25 degrees ) immediately after surgery, and 19 degrees (range 12 degrees -27 degrees ) at the last follow-up. The pelvic obliquity improved from a mean of 17 degrees (range 14 degrees -20 degrees ) preoperatively to a mean of 6 degrees (range 4 degrees -9 degrees ) postoperatively and to 7 degrees (range 4 degrees -10 degrees ) at the last follow-up. Balanced sitting posture was achieved and maintained. On the sagittal plane, good reconstruction of sagittal plane alignment was recreated and maintained. There were no major complications or deaths. All patients/parents completed the outcome satisfaction questionnaire. Eight patients/parents were very satisfied and two were satisfied.

CONCLUSIONS

Pedicle-screw-alone fixation and fusion to L5 was safe and effective in CMD patients with scoliosis of <95 degrees and pelvic obliquity of <20 degrees . Scoliosis curves were flexible (75% correction) on side-bending films preoperatively. Curve correction and maintenance of correction in the coronal and sagittal plane was excellent. The pelvic obliquity significantly improved. Balanced sitting posture was achieved and maintained in all patients. Our patients with CMD spinal deformity and a moderately and severely decreased FVC could be operated on safely and successfully with general anesthesia. All patients were extubated in the operating room. There were no major complications or deaths. We believe a FVC of <30% alone is not a predisposition to pulmonary complications. However, cardiomyopathy might be a determining risk of mortality, and we believe surgery for these patients should be avoided. Patients' and parents' satisfaction was high.

Duchenne muscular dystrophy: Canadian paediatric neuromuscular physicians survey

BACKGROUND

Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy in childhood.

METHOD

To assess the current care of paediatric DMD patients in Canada, a questionnaire was mailed to 17 physicians who were members of the Canadian paediatric neuromuscular group. Areas of enquiry included; 1) multidisciplinary team composition; 2) means of DMD diagnosis; 3) corticosteroid use; surveillance and management for: 4) orthopaedic, 5) respiratory and 6) cardiac complications and 7) health maintenance (nutrition & immunizations).

RESULTS

Completed surveys were returned by 14/17 (82%) of physicians. Twelve respondents followed DMD patients. All centres had multidisciplinary teams, including respirology (11/12), child neurology or physiatry (11), physiotherapy (9), occupational therapy (9) and orthopaedic surgery (7). Deflazacort 0.9 mg/kg/d was used at all centres, which was continued after loss of independent ambulation (11), along with routine calcium and vitamin D supplementation (10). Night splints were prescribed at all centres. Routine surveillance studies included pulmonary function testing (11), sleep studies (10), EKG/echocardiogram (10), bone density (DEXA) scans (10), spine radiography (9), and dietician referral (4).

CONCLUSION

Paediatric DMD patients are receiving relatively consistent care in multidisciplinary clinics across Canada, in accordance with recommended guidelines for DMD.

Surgical management of severe scoliosis with high risk pulmonary dysfunction in Duchenne muscular dystrophy: patient function, quality of life and satisfaction

In a previous study, the authors reported the clinical and radiological results of Duchenne muscular dystrophy (DMD) scoliosis surgery in 14 patients with a low FVC of <30%. The purpose of this study was to determine if surgery improved function and QOL in these patients. Furthermore, the authors assessed the patients' and parents' satisfaction. %FVC increased in all patients after preoperative inspiratory muscle training. Scoliosis surgery in this group of patients presented no increased risk of major complications. All-screw constructions and fusion offered the ability to correct spinal deformity in the coronal and pelvic obliquity initially, intermediate and long-term. All patients were encouraged to continue inspiratory muscle training after surgery. The mean rate of %FVC decline after surgery was 3.6% per year. Most patients and parents believed scoliosis surgery improved their function, sitting balance and quality of life even though patients were at high risk for major complications. Their satisfaction was also high.

Autogenous iliac crest bone graft versus banked allograft bone in scoliosis surgery in patients with Duchenne muscular dystrophy

A total of 36 consecutive nonambulatory DMD patients underwent scoliosis surgery. Patients were divided into two groups: the autogenous iliac crest bone graft group (the ICBG group; 20 patients) and the allogenous bone graft group (the ALBG group; 16 patients). The mean preoperative curves measured 87 degrees and 31 degrees at the last follow-up in the ICBG group and 83 degrees and 28 degrees in the ALBG group. In the ICBG group, three (15%) patients had intraoperative sacroiliac joint penetration, five (25%) had iliac crest inner cortex penetration and three (15%) had postoperative prolonged wound drainage at the donor site. At three months after surgery, donor site pain caused by bone harvest was found in 50% with severe pain limiting their physical function and causing difficulties in sitting in a wheelchair in 40% of the patients, whereas patients in the ALBG group returned to their preoperative level of function soon after surgery.

A Dutch guideline for the treatment of scoliosis in neuromuscular disorders

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.

Scoliosis correction with pedicle screws in Duchenne muscular dystrophy

This report describes the spinal fixation with pedicle-screw-alone constructs for the posterior correction of scoliosis in patients suffering from Duchenne muscular dystrophy (DMD). Twenty consecutive patients were prospectively followed up for an average of 5.2 years (min 2 years). All patients were instrumented from T3/T4 to the pelvis. Pelvic fixation was done with iliac screws similar to Galveston technique. The combination of L5 pedicle screws and iliac screws provided a stable caudal foundation. An average of 16 pedicle screws was used per patient. The mean total blood loss was 3.7 l, stay at the intensive care unit was 77 h and hospital stay was 19 days. Rigid stabilisation allowed immediate mobilisation of the patient in the wheel chair. Cobb angle improved 77% from 44 degrees to 10 degrees, pelvic tilt improved 65% from 14 degrees to 3 degrees. Lumbar lordosis improved significantly from 20 degrees to 49 degrees, thoracic kyphosis remained unchanged. No problems related to iliac fixation, no pseudarthrosis or implant failures were observed. The average percentage of predicted forced vital capacity (%FVC) of the patients was 55% (22-94%) preoperatively and decreased to 44% at the last follow-up. There were no pulmonary complications. One patient with a known cardiomyopathy died intraoperatively due to a sudden cardiac arrest. The rigid primary stability with pedicle screws allowed early mobilisation of the patients, which helped to avoid pulmonary complications.

Posterior spinal fusion for scoliosis in duchenne muscular dystrophy diminishes the rate of respiratory decline

STUDY DESIGN

To assess the rate of decline in pulmonary function in Duchenne muscular dystrophy (DMD) before and after posterior spinal fusion for scoliosis.

OBJECTIVE

To compare the rate of respiratory decline using percent normal forced vital capacity (%FVC) measurements before and after posterior spinal fusion.

SUMMARY OF BACKGROUND DATA

Posterior spinal fusion for scoliosis is used widely in DMD, although the long-term pulmonary effects have not been well established.

METHODS

Fifty-six patients were assessed. Percent forced vital capacity was the outcome parameter with data analysis using a mixed-model repeated-measures ANOVA and paired t tests. Group 1: Inclusion criteria were a diagnosis of DMD, 2 or more pulmonary function tests presurgery, and 2 or more postsurgery. Group 2: The rates of respiratory decline before and after spinal fusion for the whole study population were determined by within-subjects mixed-model regression analysis to account for the varying number of FVC studies between patients and unequal spacing between tests.

RESULTS

Group 1: 20 patients. Mean length of time of respiratory value determination was 2.5 +/- 1.0 years presurgery and 5.6 +/- 2.8 years postsurgery. Mean rate of decline presurgery was 8.0% +/- 4.1% per year, which decreased to 3.9% +/- 1.9% per year postsurgery (paired t test = 4.58, P < 0.0001). Group 2: 56 patients. The respiratory value determinations ranged from 4 years presurgery to 8 years postsurgery. The rates of respiratory decline based on the whole study population were 4% per year presurgery, which decreased to 1.75% per year postsurgery (F-test comparison of slopes = 19.71, P < 0.0001).

CONCLUSIONS

Posterior spinal fusion for scoliosis in DMD is associated with a significant decrease in the rate of respiratory decline postsurgery compared with presurgery rates.

Surgery for scoliosis in Duchenne muscular dystrophy

BACKGROUND

Scoliosis in people with Duchenne muscular dystrophy is usually progressive and treated with surgery. However, it is unclear whether the existing evidence is sufficiently scientifically rigorous to support a recommendation for spinal surgery for most people with Duchenne muscular dystrophy and scoliosis.

OBJECTIVES

The objectives of this systematic review were to determine the effectiveness and safety of spinal surgery in Duchenne muscular dystrophy patients with scoliosis. We intended to test whether spinal surgery is effective in increasing life expectancy, improving respiratory function, improving quality of life and overall functioning; and whether spinal surgery is associated with severe adverse effects.

SEARCH STRATEGY

We searched the specialized registers of the Cochrane Neuromuscular Disease Group and Cochrane Back Group, the Cochrane Central Register of Controlled Trials (January 2006), MEDLINE (January 1966 to January 2006), EMBASE (January 1980 to January 2006), Dissertation Abstracts International (1861 to Jan 2006), CINAHL (January 1982 to January 2006), and the National Institute of Health Clinical Trials Database (January 2006). No language restrictions were imposed.

SELECTION CRITERIA

Controlled clinical trials using random or quasi-random allocation of treatment evaluating all forms of spinal surgery for scoliosis in patients with Duchenne muscular dystrophy were to be included in the review. The control interventions would have been no treatment, non-operative treatment, or a different form of spinal surgery.

DATA COLLECTION AND ANALYSIS

Two authors examined the search results and evaluated the study characteristics against inclusion criteria to decide which ones would be included in the review.

MAIN RESULTS

A total of 402 studies were identified from electronic searching. Thirty-six studies were relevant but none met the inclusion criteria for the review, because they were not clinical trials but prospective or retrospective reviews of case series.

AUTHORS' CONCLUSIONS

Since there were no randomized controlled clinical trials available to evaluate the effectiveness of scoliosis surgery in people with Duchenne muscular dystrophy, no evidence-based recommendation can be made for clinical practice. Patients should be informed about the uncertainty of benefits and potential risks of surgery for scoliosis. Randomized controlled trials are needed to investigate the effectiveness of scoliosis surgery, in terms of patients' quality of life, functional status, respiratory function and life expectancy.

Correction of neuromuscular scoliosis in patients with preexisting respiratory failure

STUDY DESIGN

A prospective observational study in scoliosis patients who were on noninvasive night ventilation for respiratory failure.

OBJECTIVE

To report the results of spinal deformity correction in a group of patients with progressive scoliosis and rare forms of muscular dystrophy/myopathy with respiratory failure who were on nocturnal ventilatory support at the time of surgery.

SUMMARY OF BACKGROUND DATA

This is the first study on the results of deformity correction in a series of patients on ventilatory support.

MATERIALS AND METHODS

Eight patients (6 males, 2 females) presented with progressive scoliosis and respiratory failure. The mean age at surgery was 12 years (range, 8-15 years). The mean follow-up was 48 months (range, 12-80 months). Outcome measures include lung function (spirometry), overnight pulse oximetry, Cobb angles, duration of stay in Intensive care (ICU), and the total hospital stay.

RESULTS

The mean stay in the ICU was 2.7 days (range, 2-5 days). The mean hospital stay was 14.2 days (range, 10-21 days). The mean preoperative Cobb angle was 70.2 degrees (55 degrees -85 degrees ). This changed to 32 degrees (16 degrees -65 degrees ) after surgery (P = 0.0002). The mean vital capacity at the time of surgery was 20% (range, 13%-28%). The mean vital capacity of patients at last follow-up was 18% (range, 10%-31%). The desaturation noted on the preventilation overnight oximetry was reversed by nocturnal ventilation. All patients recovered well following surgery with no major cardiac or pulmonary complications.

CONCLUSION

Patients with preexisting respiratory failure on nocturnal noninvasive ventilation can be safely operated for deformity correction. This can help to significantly improve their quality of life.

Corticosteroid Treatment and Functional Improvement in Duchenne Muscular Dystrophy

OBJECTIVE

To determine and compare the long-term effects of prednisone and deflazacort on the functional status of children with Duchenne muscular dystrophy.

DESIGN

A total of 49 boys with Duchenne muscular dystrophy, between the age of 12 and 15 yrs, who were observed over a 7-yr period were reviewed retrospectively. Eighteen had been treated with prednisone, 12 with deflazacort, and 19 had no drug treatment. All boys treated with steroids received medication for >2 yrs before losing their ambulation. Lower and upper limb motor functions, pulmonary function, prevalence of surgery for scoliosis, and side effects were compared.

RESULTS

Boys in the steroid groups were significantly more functional and performed better on all tests than boys not treated (P < 0.05). There was no significant difference between the deflazacort- and prednisone-treated groups (P > 0.05). The number of boys having scoliosis surgery in treated groups was significantly less than nontreated boys (P < 0.05). The control group's pulmonary capacity was decreasing and significantly less than both prednisone- and deflazacort-treated boys. Both deflazacort and prednisone had beneficial effect on pulmonary function and scoliosis. Cataracts, hypertension, behavioral changes, excessive weight gain, and vertebral fracture were noted as serious side effects.

CONCLUSIONS

Prednisone and deflazacort have a significant beneficial effect on slowing the disease progress. Their usage in Duchenne muscular dystrophy may prolong ambulation and upper limb function with similar potency. Both steroids also improve pulmonary function, in addition to delaying the need for spinal interventions, with similar therapeutic profiles.

Analysis of an adult Duchenne muscular dystrophy population

BACKGROUND

Advances in management have led to increasing numbers of patients with Duchenne muscular dystrophy (DMD) reaching adulthood. Older patients with DMD are necessarily severely disabled, and their management presents particular practical issues.

AIM

To review the management of a late adolescent and adult DMD population, and to identify areas in which the present service provisions may be inadequate to their needs.

DESIGN

Retrospective review.

METHODS

We studied 25 patients with DMD referred to an adult neuromuscular clinic over a 7-year period. Clinical details were obtained retrospectively, from case notes or direct observations.

RESULTS

There were 24 males and one symptomatic female carrier. Nine patients died during the observation period. There was no significant correlation between age of wheelchair confinement and age of death. Sixteen patients received non-invasive positive pressure support. Twelve attended mainstream schools and 12, residential special schools. All the patients lived at home for some or all of the time, when their main carers were either one or both of the parents. The most striking difficulties were with the provision of practical aids, including appropriate hoists and belts, feeding and toileting aids, and the conversion of accommodation. Patients rarely wished to discuss the later stages of their disease, and death was often more precipitate than expected. Death usually occurred outside hospital and the final cause was often difficult to establish.

DISCUSSION

Adult patients with DMD develop progressive impairment, due to respiratory, orthopaedic and general medical factors. However, the particular areas of difficulty in this study often reflected inadequate and poorly directed social and medical support, illustrating the need for improvements in the structure, co-ordination and breadth of rehabilitation services for adult patients with DMD.

Anaesthesia for correction of scoliosis in children

Surgical correction of spinal deformities in children presents a challenge to the anaesthetist because of the extensive nature of the surgery, the co-morbidities of the patients and the constraints on anaesthetic techniques of intraoperative neurophysiological monitoring of the spinal cord. Adolescent idiopathic scoliosis is the most common deformity. Patients with scoliosis secondary to neuromuscular conditions are at greatest risk of perioperative problems, particularly excessive blood loss and respiratory failure. The risk of spinal cord damage can be decreased by the use of intraoperative spinal cord monitoring, particularly monitoring of the lower limb compound muscle action potential evoked by transcranial electrical stimulation. Specific anaesthetic techniques are required for this monitoring to be reliable. Because of concerns about spinal cord perfusion there is now less reliance on induced hypotension and haemodilution to reduce blood loss, with emphasis on proper patient positioning, controlled haemodynamics and antifibrinolytic therapy. Effective postoperative pain management requires a multimodal approach.

Surgical treatment of spinal deformities in Duchenne muscular dystrophy: a long term follow-up study

BACKGROUND

Surgical treatment of spinal deformities in Duchenne muscular dystrophy (DMD) is influenced by a number of factors which have proven to be a difficult challenge. Each case should be carefully evaluated, considering not only the natural history of the spinal deformity, but also the patient's general condition. These should be thoroughly assessed through clinical and radiographic investigations together with other medical specialists. Life expectancy should be determined according to the cardio-respiratory function, and both preoperative and postoperative quality of life should be taken into consideration, trying to imagine the functional status of each patient after surgery.

METHODS

From February 1985 to February 2000, 58 patients with spinal deformity in DMD were surgically treated. Of 25 patients that were operated on between 1985 and 1995, only 20 were followed-up after 5 years because 5 of them had died during this time. Therefore, the present study focuses on the results obtained in 20 cases. The 20 cases reviewed presented with a mean angular value of scoliosis equal to 48 degrees (range 10-92 degrees). Spinal fusion with our modified Luque technique [6] was performed in 19 cases, whereas CD instrumentation was applied in only one case.

RESULTS

At the 5 year follow-up (range 5.6-10 years), the age ranged from 18 to 24 years and averaged 20.4 years. The postoperative angular value of scoliosis averaged 22 degrees (58%, range 0-43 degrees), the mean correction at follow-up was 28 degrees (range 0-60 degrees), and the mean loss of correction was equal to 6 degrees (range, 0-11 degrees). Vital capacity showed a slow progression, slightly inferior to its natural evolution in untreated patients. The severest complication was the death that occurred in one of the patients.

CONCLUSIONS

According to the present study, an early surgery (angular value lower than 35-40 degrees) dramatically reduces the rate of risk factors associated with spinal deformities in DMD, and its advantages far exceed the disadvantages, above all in terms of quality of life.

Perisurgical management of patients with neuromuscular disorders

Patients with neuromuscular disorders who undergo surgical procedures are particularly predisposed to complications during the perioperative period. Such complications may arise from respiratory failure, arrhythmias,or infections, and particularly MH. It is recommended that these patients be monitored for respiratory and cardiovascular complications and receive proper respiratory toilet, physio-therapy, and incentive respirometry. Proper electrolyte balance is mandatory. They should be monitored in the ICU when necessary. Excessive sedation of these patients, and drugs that could aggravate weakness or cause MH, should be avoided. Those at risk of MH should not receive drugs that may precipitate an attack.

Spinal fusion in patients with Duchenne's muscular dystrophy and a low forced vital capacity

Traditionally, spinal fusion has been denied to patients with scoliosis secondary to Duchenne's muscular dystrophy (DMD) when their forced vital capacity (FVC) is less than 30-40% of predicted values (PFVC). The reasons for this decision are a theoretically increased risk of adverse events from a prolonged anaesthetic and extensive surgery. This paper presents a retrospective analysis of 30 patients with DMD scoliosis who underwent posterior spinal fusion at the Royal National Orthopaedic Hospital. Two subgroups of patients were compared: those with more than 30% PFVC (17 patients) and those with less than 30% PVFC (13 patients). One patient in each group required a temporary tracheotomy and there were nine complications in total. The post-operative stay for patients in each group was similar (24 days in the >30% group, 20 days in the <30% group) and the complication rate was comparable with other published series. We conclude that spinal fusion can be offered to patients with DMD even in the presence of a low FVC.

Spinal fusion and instrumentation for paediatric neuromuscular scoliosis: retrospective review

PURPOSE

A retrospective study was conducted to review the surgical results among 24 patients with neuromuscular scoliosis, who were treated with spinal instrumentation and fusion at the Department of Orthopaedic Surgery, National University Hospital, Singapore between March 1993 and December 1998.

METHODS

We examined complete hospital records of patients who had scoliosis due to aetiologies such as spinal muscular atrophy, cerebral palsy, Duchenne muscular dystrophy, and congenital myopathies. The mean age of patients was 10.6 years (range, 6-14 years) and the mean follow-up duration was 5.5 years.

RESULTS

18 patients had posterior surgery alone, whereas 4 had an anterior release with posterior instrumentation, and 2 had an anterior fusion with instrumentation. The mean length of stay in the intensive care unit was 2 days and the mean duration of hospital stay was 11 days. The mean correction in scoliosis angle ranged from 75.6 degrees to 25.7 degrees. All patients could at least sit without support postoperatively. The one-second forced expiratory volume and forced vital capacity were, in general, maintained throughout the follow-up. There were 2 major complications and 2 minor ones; these were pseudarthrosis with rod breakage requiring revision, deep infection necessitating hardware removal, superficial infection that responded to antibiotics, and urinary tract infection requiring 3 weeks of antibiotic treatment. There were no deaths or any neurological complications after instrumentation.

CONCLUSION

Spinal stabilisation and fusion in children with neuromuscular scoliosis is a safe and effective treatment modality. The effect of surgery on long-term pulmonary function, however, remains controversial and needs to be addressed.

Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is not treatable; there is no cure. More than a decade ago, randomized trials demonstrated that oral steroid therapy was of benefit to DMD patients by prolonging ambulation. Although few significant side effects were reported, study patients were followed for 18 months or less. However, when treating DMD with steroids, the clinician must consider beginning treatment in mid-childhood and continuing until adolescence or longer, a total of at least 10 years. There is no evidence that steroids are associated with prolonged life or with improved pulmonary or cardiac function in DMD. It is clear that the risk of side effects increases with duration of use of oral steroids. Therefore, oral steroids are not recommended for treatment of DMD on a routine basis. If, in certain cases, one does institute therapy, the patient should be monitored carefully for side effects, maintain dietary restriction, and exercise regularly.

Congenital myasthenic syndrome with sleep hypoventilation

We report the case of a 13-year-old boy with acetylcholinesterase deficiency, a congenital myasthenic syndrome, who developed sleep hypoventilation syndrome during a period of rapid growth. His symptoms were insidious and life-threatening despite changes in strength or lung volume measurements that were not marked. He responded well to noninvasive nocturnal ventilation, with reversal of symptoms and normalization of blood gases. His lung volumes, but not motor function, improved after treatment.

Orthopedic management of neuromuscular disorders in children

In many cases, the orthopedic surgeon may be the first consultant requested to assess complaints of lower extremity weakness or deformity to result from such conditions and must remain alert to the primary diagnosis. In addition, the orthopedic surgeon should be prepared to guide appropriate physical therapy, prescribe orthotics, and perform surgery to improve function, prevent deformity, or provide comfort when necessary. Most deformities of the extremities result from a combination of muscle weakness and imbalance, and surgical procedures are aimed at correcting existing deformity and rebalancing existing musculature by release or transfer. Skeletally immature patients with neuromuscular disorders are also susceptible to the development of scoliosis, which may impair comfortable sitting or already compromised pulmonary function. This article reviews the clinical manifestation and orthopedic management of Duchenne's muscular dystrophy, spinal muscular atrophy, facioscapulohumeral dystrophy, and Charcot-Marie-Tooth disease.

Scoliosis in Duchenne muscular dystrophy: aspects of orthotic treatment

The x-linked Duchenne muscular dystrophy (DMD) is the most frequent generalized muscle disorder arising from a lack of the sarcolemmic protein "dystrophin". Patients with DMD develop in the majority a progressive scoliosis when they cease walking and/or standing at the age of 10 years and become confined to a wheelchair. Increasing muscle weakness leads to a progression of the curvature, the pelvic tilt and problems in sitting. Together with the simultaneous progressive weakness of the respiratory muscles a restrictive pulmonary insufficiency will occur. Surgical stabilization of the spine (> 20 degrees Cobb, forced vital capacity > 35%) by an adequate multisegmental instrumentation enabling early mobilization is now the treatment of choice. However, orthotic treatment may offer an acceptable compromise in exceptional cases, if the patient rejects surgical intervention or is in the late (inoperable) stages of the disease. Such a treatment is superior to a primary sitting support provision with insufficient possibilities of correction. The authors' experiences with 48 scoliosis orthoses made for 28 patients with DMD are reported. A "double plaster" cast has emerged as the best method to optimize adaption, especially in severe curvatures and the time taken for manufacturing the orthosis. A great deal of experience, patience and the consideration of the patients' individual demands are inevitable for a successful orthotic treatment.

Spinal fusion in Duchenne's muscular dystrophy

The Women's and Children's Hospital experience with Luque spinal fusion in Duchenne's muscular dystrophy was reviewed from its commencement in 1983 to the present with a view to assessing the clinical and radiologic outcome and safety of the procedure. Seventeen boys have undergone spinal fusion. L-rod instrumentation was used in 10, six of whom had significant problems with sitting imbalance or progression of the scoliosis or both. In seven cases, distal instrumentation was taken to the pelvis with a Galveston construct and rigid crosslinking. Apart from some progression and sitting imbalance in the L-rod group, there were few complications. In the Galveston group, pelvic obliquity was corrected by a mean of 63%, and there was better maintenance of correction. There were no pseudoarthroses or instrument failures in the Galveston group. Of the total group, four patients had forced vital capacity (FVC) values < 25% predicted, and two required ventilation postoperative (< 48 h). There were no other respiratory complications. The effect of surgery on respiratory function remains uncertain. Spinal fusion with the Luque rod construct and pelvic fixation is a safe procedure. It provided a mean correction of 60% and control of pelvic obliquity without significant postoperative deterioration. In our experience, surgery can be safely performed with FVC value down to 20% predicted. On the basis of these data, one current practice is to instrument to the pelvis with a Galveston construct and Texas Scottish Rite Hospital cross-linking.

Long-term results of spine surgery in Duchenne muscular dystrophy

We report the long-term orthopaedic and functional results of segmental spinal instrumentation and fusion in 30 Duchenne patients. Twenty-nine had a mean 59% correction of scoliosis with post-operative immobilization in a brace of only three months on average and with a very limited loss of correction over time. One died after cardiac arrest. The mean vital capacity preoperatively was 57 +/- 17% with a decrease to 34 +/- 13% at 3.9 +/- 2 yr after surgery. The sitting position, aesthetic improvement and the quality of life after spinal fusion have been positively evaluated by the large majority of the patients and their parents. Head control was lost in the 14 patients who developed a more severe extension contracture of the neck measured as a significantly longer chin-sternum distance. More than 90% would have the operation or would give their consent again for their son having the operation.

Effect of spinal surgery on lung function in Duchenne muscular dystrophy

BACKGROUND

The effect on subsequent respiratory function of spinal stabilisation for scoliosis in Duchenne muscular dystrophy is unclear. In order to clarify this clinical problem, changes in the forced vital capacity of a group of children with Duchenne muscular dystrophy who had undergone spinal surgery were measured and compared with a group of children with Duchenne muscular dystrophy who had not had surgery.

METHODS

In this retrospective study 17 boys with Duchenne muscular dystrophy who underwent spinal stabilisation at a mean age of 14.9 years (surgical group) were compared with 21 boys with Duchenne muscular dystrophy who had not had surgery (non-surgical group). The mean (SD) Cobb angle of the surgical group at 14.9 years was 57 (16.4) degrees, and of the non-surgical group at 15 years was 45 (29.9) degrees. Forced vital capacity expressed as percentage predicted (% FVC) was measured in total over a seven year period in the surgical group and over 6.5 years in the non-surgical group, and regression equations were calculated. Survival curves for both groups were also constructed.

RESULTS

No difference was found between spinal stabilisation (surgical group) and the non-surgical group in the rate of deterioration of % FVC which was 3-5% per year. There was no difference in survival in either group.

CONCLUSIONS

Spinal stabilisation in Duchenne muscular dystrophy does not alter the decline in pulmonary function, nor does it improve survival.

Lung function in Duchenne muscular dystrophy

Over 90% of patients with Duchenne muscular dystrophy develop a scoliosis when they become wheelchair bound. The scoliosis is progressive and is associated with deteriorating lung function. The purpose of this study was firstly to assess whether a standing regimen, in patients who had gone off their feet, protected against the development of scoliosis and affected their lung function, and secondly to evaluate the effect of spinal stabilisation in patients who had developed a progressive scoliosis. The results of the first part of this study showed that a standing regimen significantly delayed the progression of scoliosis and that patients who complied with the standing regimen had a significantly better lung function, as measured by vital capacity and peak expiratory flow rate, than those patients who did not stand. Spinal stabilisation prevented deterioration in the scoliosis, whereas the deformity continued to progress relentlessly in patients who did not undergo surgery. The patients who underwent spinal stabilisation maintained a significantly better lung function and had an improved survival compared with the patients who refused surgery.

Neuromuscular disease: rehabilitation and electrodiagnosis. 3. Muscle disease

The purpose of this section of the Self-Directed Physiatric Education Program Study Guide on rehabilitation in diseases affecting nerve and muscle is to assist practitioners and trainees in physical medicine and rehabilitation by providing practical information about inherited and acquired muscle diseases. It emphasizes clinical management issues and new developments in commonly encountered muscle disorders.

Sleep polygraphic parameters in neuromuscular diseases

In a polysomnographic study of 32 neuromuscular patients-22 with a form of muscular dystrophy, 3 with a form of congenital myopathy, 4 with a form of spinal muscular atrophy, 1 with a recurrent form of polymyositis and 1 with osteogenesis imperfecta syndrome--of which 21 were nonambulatory, we observed sleep related respiratory disturbances represented by: drops in oxygen saturation (SaO2), cardiac arrhythmia, sleep disruption, apneas, tachypnea, tachycardia and snoring. Nine out of the cohort of 32 patients presented with significant desaturations periods. These patients presented with an associated restrictive syndrome and thoracic deformities, some with tachypnea and/or SaO2 below 90% during wakefulness. In this group, snoring was observed in those patients with a form of muscular dystrophy while tachypnea was observed in patients who presented the highest desaturations levels. Sleep quantification revealed an increase of stage 1 sleep coupled with a decrease or even total absence of REM sleep. This is, we believe, a likely consequence of episodic desaturations that may accompany sleep hypoventilation which is potentialised during REM sleep stage.

End of life care in Duchenne muscular dystrophy

End of life care for patients with Duchenne muscular dystrophy (DMD) has become increasingly complex because of new technologies, changes in medical personnel over periods of time, emergence of home health care systems, and increasing patient and family autonomy in decision-making. In this review, we discuss the medical problems, particularly respiratory and cardiac failure, faced by DMD patients. Current concepts concerning the evaluation and options for treatment of these problems are presented as well as the ethical issues involved in the care of the DMD patient. These issues include the medical indications for treatment, patient preferences, quality-of-life issues, and contextual features related to legal, institutional, religious, geographic, cultural, social, and financial factors. We also present our experience at Loma Linda University Medical Center over the past 10 years in the development of a home mechanical ventilation program for DMD patients and an algorithm for the evaluation of these patients. Many patients with DMD do well on long-term ventilation, but some find that their quality of life is less than desirable and choose to discontinue this method of life-prolongation. Many of these new options are very expensive, making the decision to use them a difficult one. Ultimately, these are societal issues that require clear reflection on matters of resource allocation that should be performed by health care professionals, citizens, and health planners.

Current status of Duchenne muscular dystrophy

Duchenne muscular dystrophy is the second most common lethal genetic disorder in humans. With the advent of molecular genetic technology, the definition of this disease has been modified to include an abnormality of dystrophin in muscle--a dystrophinopathy. Accurate genetic counseling is possible using methods of deletion detection and linkage analysis. Treatment of this type of muscular dystrophy may soon mean the routine use of steroids and later include direct injection of an artificial gene for dystrophin.