Duchenne muscular dystrophy (DMD) is an inherited X-linked muscular dystrophy caused by mutations in the dystrophin gene. It is characterized by progressive dystrophic changes in skeletal and cardiac muscle. Progressive weakness in affected children results in loss of ambulation at a mean age of 9.5 years (Van Essen 1997). There is progressive cardiomyopathy and respiratory failure occurs secondary to respiratory muscle weakness. The mean survival in the absence of ventilatory support is 19.5 years (Van Essen 1997). In 90% death is the result of respiratory failure and in 10% the result of cardiac involvement. Currently there is no proven effective curative treatment for this debilitating disease. A systematic review has found that glucocorticoid therapy improves muscle strength and function in the short-term. However, adverse effects were common and long-term benefits are uncertain (Manzur 2008).
Spinal deformity, especially scoliosis, is progressive in the majority of people with DMD (Galasko 1995; Miller 1985). From the onset of spinal deformity, progression can be extremely rapid and impair unsupported sitting ability and further compromise the respiratory and cardiac function (Hsu 1983). Kurz observed a 4% decrease in vital capacity for every 10% progression of the spinal curve in people with DMD (Kurz 1983). Galasko found that on average, vital capacity decreases by 8% per year in patients with scoliosis secondary to DMD (Galasko 1992). Long-term corticosteroid treatment may slow the progress of scoliosis in people with DMD and may reduce the need for surgery (Dooley 2010), but adverse effects are frequent (Alman 2004). Non-operative treatment such as bracing might not prevent the progression of this kind of spinal deformity because of the progressive nature of the underlying muscle disease (Cambridge 1987; Colbert 1987). Therefore, non-operative treatment is usually considered only in exceptional cases when a person refuses surgery or when a person has a very advanced deformity with poor general health (Forst 1997; Heller 1997; McCarthy 1999).
Spinal fusion surgery with instrumentation remains the mainstay of treatment for people with DMD with scoliosis. Commonly used techniques are either based on sublaminar segmental wiring, such as Luque instrumentation, or the modern variants based on segmental pedicle screw and hook fixation such as Isola, TSRH or Universal Spine system. Two stainless steel or titanium rods are contoured to the desired spinal shape, and the spine reduced onto the rods, either with the sublaminar wires or segmental screws and hooks. Pelvic fixation is rarely required in DMD scoliosis and the Galveston technique of rod insertion into the ileum, or more modern screw fixation can be used in some circumstances. Postoperative bracing is not required with modern fixation techniques.
The potential advantages of surgery described in the literature include increased comfort and sitting tolerance (Bridwell 1999; Cambridge 1987; Marchesi 1997; Matsumura 1997; Miller 1991; Miller 1992; Rice 1998; Rideau 1984; Shapiro 1992), cosmetic improvement (Bellen 1993; Bridwell 1999), no need for orthopaedic braces (Bellen 1993; Colbert 1987; Miller 1985; Noble Jamieson 1986), easier nursing care by parents (Bellen 1993) and pain relief (Bellen 1993; Galasko 1977; Miller 1991).
Nevertheless, the effects of spinal surgery on respiratory function and life expectancy are still controversial. Some studies reported that spinal fusion had no effects on the natural deterioration of respiratory function of people with DMD (Kinali 2006; Miller 1988; Miller 1992; Shapiro 1992), at short-term and five-year follow-up (Miller 1991). In contrast, several studies (Galasko 1992; Galasko 1995; Rideau 1984; Velasco 2007) reported stabilization of vital capacity in people surgically treated for two to eight years. Regarding life expectancy, Galasko observed a lower mortality in people surgically treated (Galasko 1992; Galasko 1995). However, other studies reported that spinal surgery did not improve life expectancy (Chataigner 1998; Gayet 1999; Kennedy 1995; Kinali 2006; Miller 1988). Adverse effects and complications during and after surgery are not uncommon, including ventilator-associated pneumonia (iatrogenic, in the post-operative period), wound dehiscence, surgical wound infection, haemorrhage, loosening of fixation, pseudarthrosis, deteriorated respiratory function and increased difficulty with hand to head motions.
A randomized trial has demonstrated that although tendon surgery in people with DMD may correct deformities, it might also result in more rapid deterioration of function in some patients and there were no beneficial effects on strength or function (Manzur 1992). With increasing use of non-invasive ventilation (NIV) in DMD patients with respiratory insufficiency which may prolong the life expectancy, it is unclear to what extent increased survival is related to NIV rather than to other interventions, including scoliosis surgery. It remains uncertain whether the existing evidence is sufficiently scientifically rigorous to recommend spinal surgery for most patients with DMD and scoliosis. In this systematic review, we evaluated the effectiveness of various forms of spinal surgery to prolong life expectancy, retard the natural deterioration of respiratory function, and improve quality of life in people with DMD. We wanted to evaluate whether the benefits outweigh the risks of surgery in general and determine which patient subgroups are most likely to benefit. The review has been updated, most recently in 2012.
The objectives of this systematic review were to determine the effectiveness and safety of spinal surgery in people with DMD with scoliosis. We intended to test the following hypotheses:
- Whether spinal surgery is effective in increasing survival;
- Whether spinal surgery can improve respiratory function in the short-term and long-term;
- Whether spinal surgery can improve quality of life and overall functioning;
- Whether spinal surgery is associated with severe adverse effects.
Criteria for considering studies for this review
Types of studies
We planned to include controlled clinical trials using random or quasi-random allocation of treatment in the review.
Types of participants
People with Duchenne muscular dystrophy (defined as progressive limb girdle weakness with at least one of: (1) dystrophic changes on muscle biopsy with reduced or absent dystrophin staining; (2) deletion, duplication or point mutation of dystrophin gene) and all degrees of scoliosis documented by appropriate x-rays would be included.
It was possible that this definition might have resulted in the inclusion of some individuals with an intermediate or severe Becker phenotype. However, the inclusion of only biopsy proven dystrophin negative cases could potentially result in the loss of some important data.
Types of interventions
We planned to include trials evaluating all forms of spinal surgery for scoliosis in the review. The control interventions were to be no treatment, non-operative treatment, or a different form of spinal surgery.
Types of outcome measures
- Survival: to allow for studies using different follow-up periods, we planned to use hazard ratios from survival data regression analysis.
- Respiratory function, as measured by pulmonary function tests such as forced vital capacity (FVC): medium-term (3 to 12 months), and long-term (more than 12 months). The results from studies with differing lengths of follow-up were to be weighted appropriately to allow for this.
- Medium and long-term disability as measured by validated scales such as the Barthel index or Functional Independent Measure.
- Medium and long-term quality of life as measured by validated scales such as the 36-Item Short-Form Health Status Survey (SF-36).
- Rate of progression of scoliosis, as measured by change of Cobb angle per year.
- Frequency of severe adverse effects and complications, such as death related to surgery, deep surgical wound infection, wound dehiscence, loosening of fixation, pneumonia, pseudarthrosis, need for revision surgery.
Search methods for identification of studies
We searched the specialized registers of the Cochrane Neuromuscular Disease Group (31 July 2012) using the terms surgery, spine, spinal, vertebra, vertebrae, spinal fusion, scoliosis, Duchenne Muscular Dystrophy and Duchenne. We also searched 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).
The detailed search strategies in the appendices: MEDLINE (Appendix 1), EMBASE (Appendix 2), CENTRAL (Appendix 3), CINAHL Plus (Appendix 4), Proquest Dissertation and Thesis Database (Appendix 5), and NIH Clinical Trials (Appendix 6).
There was no language restriction in the search and inclusion of studies. However, multiple publications reporting the same group of patients or its subsets were excluded.
Searching other resources
The review authors searched the reference lists of all relevant papers for further studies. The process of searching many different sources might have brought to light direct or indirect references to unpublished studies. We planned to seek to obtain copies of such unpublished material. In addition, we contacted colleagues and experts in the field to ascertain any unpublished or ongoing studies.
Data collection and analysis
Selection of studies
Two review authors independently reviewed titles and abstracts of references retrieved from the searches and selected all potentially relevant studies. Copies of these articles were obtained, and reviewed independently by the same authors against the inclusion criteria of the study. Review authors were not blinded to the names of the trial authors, institutions or journal of publication. The authors planned to extract data from included trials and assess trial quality independently. All disagreements would be resolved by consensus.
Data extraction and management
We would have extracted the following data:
(1) Study methods
(a) Design (e.g. randomized or quasi-randomized).
(b) Randomization method (including list generation)
(c) Method of allocation concealment
(d) Blinding method
(e) Stratification factors
(a) Inclusion/exclusion criteria
(b) Number (total/per group)
(c) Age distribution
(d) Severity of scoliosis
(e) Level of scoliosis
(f) Baseline respiratory function
(g) Associated morbidities, e.g. cardiomyopathy
(h) Previous treatments, including corticosteroids
(i) Pre-treatment quality of life and functional status, as measured by validated scales
(3) Intervention and control
(a) Type of spinal surgery
(b) Type of control
(d) Details of control treatment including duration of non-operative treatment
(e) Details of co-interventions
(4) Follow-up data
(a) Duration of follow-up
(b) Loss to follow-up
(5) Outcome data as described above
(6) Analysis data
(a) Methods of analysis (intention-to-treat/per-protocol analysis)
(b) Comparability of groups at baseline (yes/no)
(c) Statistical techniques
We planned that data would be entered into Review Manager (RevMan) by one review author and then checked by the second author.
Assessment of risk of bias in included studies
We planned to evaluate the validity of the trials by the following criteria:
(1) Selection bias
(a) Was allocation of participants to treatment and control groups randomized?
(b) Was allocation concealed?
(2) Performance bias
(a) Were participants in the comparison groups treated differently apart from the study treatments?
(b) Was there blinding of participants and personnel?
(3) Attrition bias
(a) Were there systematic differences between the comparison groups in the loss of participants from the study?
(b) Were analyses by intention-to-treat?
(4) Detection bias
(a) Were those assessing outcomes of the intervention blinded to the assigned intervention?
(5) Reporting bias
(a) Were there systematic differences between reported and unreported findings (incomplete outcome data)?
We planned to summarize the quality of a trial into one of the three categories:
A. Low risk of bias: all the validity criteria met.
B. Moderate risk of bias: one or more validity criteria partly met but none are not met.
C. High risk of bias: one or more criteria not met.
Measures of treatment effect
We planned to use risk ratio (RR) estimations with 95% confidence intervals (CI) for binary outcomes. We planned to use mean difference estimations with 95% CI for continuous outcomes. All analyses would include all participants in the treatment groups to which they were allocated.
Dealing with missing data
We planned to contact authors of included studies to supply missing data. We would have assessed missing data and drop-outs/attrition for each included study, and assess and discuss the extent to which the results and conclusions of the review could be altered by the missing data. If less than 70% of patients allocated to the treatments were not reported on at the end of the trial, for a particular outcome, we would not use those data as they would have been considered to be too prone to bias.
Assessment of heterogeneity
We planned to assess clinical heterogeneity by comparing the distribution of important participant factors between trials (age, respiratory function, severity and level of scoliosis, associated diseases), and trial factors (randomization concealment, blinding of outcome assessment, losses to follow-up, treatment type, co-interventions). We would assess statistical heterogeneity by examining I
Assessment of reporting biases
We would have drawn funnel plots (estimated differences in treatment effects against their standard error) if sufficient studies were found. Asymmetry could be due to publication bias, but could also be due to a relationship between trial size and effect size. In the event that a relationship was found, we would examine clinical diversity of the studies (Egger 1997).
Where the interventions were the same or similar enough, we planned to synthesize results in a meta-analysis if there was no important clinical heterogeneity. If no significant statistical heterogeneity was present, we planned to synthesize the data using a fixed-effect model. Otherwise we would use a random-effects model for the meta-analysis.
Since adverse events were rarely adequately dealt with by randomized studies alone because the numbers were small and follow-up too short, we planned to discuss adverse events taking into account the non-randomized literature.
We planned to consider cost-effectiveness of interventions where relevant data were available.
Subgroup analysis and investigation of heterogeneity
If data permitted, we planned to conduct sub-group analyses for:
- different age groups (younger than 12 years, 12 to 18 years, older than 18 years);
- different degrees of pre-existing respiratory impairment (mild, severe);
- different severity of scoliosis (moderate, severe);
- previous corticosteroid treatments (yes, no).
We planned to undertake sensitivity analyses to assess the impact of study quality. These would have been undertaken including:
- all studies;
- only those with low risk of selection bias;
- only those with low risk of performance bias;
- only those with low risk of attrition bias;
- only those with low risk of detection bias.
Sensitivity analysis would also be performed including and excluding subjects who might have Becker muscular dystrophy or an intermediate phenotype to see whether this would alter any of the results.
Description of studies
In July 2012, a total of 80 studies were found on electronic search of the databases (Cochrane Neuromuscular Disease Group Registry: 2 studies, MEDLINE: 17 studies, EMBASE: 11 studies, CENTRAL: 1 study, CINAHL Plus: 13 studies, Proquest Dissertation and Thesis Database: 35 studies, and NIH Clinical Trials Database: 1 study). An additional 32 studies were identified on searching the reference lists of relevant studies. After duplicates were removed, a total of 105 studies were screened. Fifty-eight of these studies were excluded as they did not focus on Duchenne muscular dystrophy or scoliosis surgery, or were narrative reviews. We examined the remaining 47 studies in detail but none of these satisfied the inclusion criteria. All these studies were prospective or retrospective case series and were not clinical trials. Most of these reviews also did not have a control group for comparisons. Where a control group was included, the controls were people who refused surgery or were assigned a different treatment modality by the treating surgeons without randomization or quasi-randomization. We therefore excluded these studies from further analyses because of significant propensity for confounding and bias. The flow of studies is shown in Figure 1.
|Figure 1. Study flow diagram.|
Risk of bias in included studies
Effects of interventions
No controlled trials met the inclusion criteria of the review for further analyses.
Despite a comprehensive search strategy used for this review, no randomized controlled trial (RCT) of surgery for scoliosis in people with Duchenne muscular dystrophy was identified. Instead we found many retrospective reviews or case series of patients with Duchenne muscular dystrophy and scoliosis treated with surgery. These studies showed varying results and had different conclusions. Although most agreed that surgery can improve patients' quality of life and functional status in terms of sitting posture, upper limb function and ease of care, most failed to show a significant improvement in respiratory function or long-term survival, and short-term and long-term postoperative complications occurred not uncommonly.
However, a closer look at the relevant studies excluded might be helpful for guiding future clinical trials of scoliosis surgery for patients with DMD ( Table 1). These 47 case series included 5 to 70 patients who had undergone scoliosis surgery. Nine of these studies also included a comparison group of 21 to 115 patients without surgery (Eagle 2007; Galasko 1992; Galasko 1995; Kennedy 1995; Kinali 2006; Miller 1988; Miller 1991; Miller 1992; Sakai 1977).
Outcome measures and comparisons
The studies had different objectives and focused on different outcomes. Most studies aimed to investigate whether spinal surgery improves the degree of scoliosis in the short-term (immediate post-operative period) and in the long-term (years later). Most studies used Cobb angle and degree of pelvic obliquity as outcome measures and described early and late complications of surgery. Some studies also reported duration of hospitalization (Harper 2004; Rideau 1984; Sengupta 2002; Sussman 1984), peri-operative mortality (Alman 1999; Bentley 2001; Brook 1996; Cambridge 1987; Cervellati 2004; Chataigner 1998; Dubousset 1983; Eagle 2007; Gaine 2004; Galasko 1992; Galasko 1995; Gayet 1999; Granata 1996; Hahn 2008; Harper 2004; Heller 2001; Hopf 1994; Kennedy 1995; LaPrade 1992; Marchesi 1997; Marsh 2003; Matsumura 1997; Modi 2009; Rideau 1984; Sakai 1977; Sengupta 2002; Shapiro 1992; Thacker 2002; Weimann 1983) and length of survival (Eagle 2007; Kinali 2006; Miller 1992) in people who had undergone scoliosis surgery. Many studies reported the change in respiratory function after operation (Brook 1996; Cervellati 2004; Chataigner 1998; Dubousset 1983; Eagle 2007; Galasko 1992; Galasko 1995; Gayet 1999; Granata 1996; Kennedy 1995; Kinali 2006; Matsumura 1997; Mehdian 1989; Miller 1988; Miller 1991; Miller 1992; Rideau 1984; Shapiro 1992; Thacker 2002; Velasco 2007). The parameters used included vital capacity, peak expiratory flow rate and forced vital capacity in one second. A few studies also reported patient oriented subjective outcomes such as quality of life, self-image, cosmetic appearance, pain and patient satisfaction (Bentley 2001; Bridwell 1999; Granata 1996; Matsumura 1997; Miller 1991; Miller 1992; Rideau 1984). While most studies evaluated the outcomes of spinal surgery in general, some studies tried to compare different surgical techniques, such as Luque instrumentation versus Isola pedicle screw (Gaine 2004), sublaminar wiring versus intraspinous segmental wiring (LaPrade 1992), Lugue instrumentation versus distal instrumentation with Galveston construct and rigid cross-linking (Brook 1996), Harrington-Lugue instrumentation versus modified Luque instrumentation (Bentley 2001), Harrington instrumentation versus Luque instrumentation versus segmental spinal instrumentation with fusion (Sussman 1984), sublaminar instrumentation versus pedicle screw versus a hybrid system (Arun 2010), or autogenous versus allogenous bone graft (Nakazawa 2010). Some studies also compared the outcomes of spinal fusion to different extents (Alman 1999; Bridwell 1999; Gaine 2004; Mubarak 1993; Sengupta 2002; Modi 2010), such as fusion to L5 versus fusion to sacrum. Some studies compared surgical outcomes in patients with different pre-operative respiratory function (Harper 2004; Marsh 2003; Matsumura 1997; Sussman 1984).
Outcomes on survival
Most studies did not demonstrate obvious benefits of scoliosis surgery in terms of prolonging survival (Brook 1996; Cervellati 2004; Chataigner 1998; Gayet 1999; Granata 1996; Hahn 2008; Kennedy 1995; Kinali 2006; Mehdian 1989; Miller 1988; Miller 1991; Miller 1992; Shapiro 1992; Thacker 2002). There was one study showing that when combined with nocturnal ventilation, patients after spinal surgery has longer median survival (30 years) compared with patients on nocturnal ventilation alone (22.2 years) (Eagle 2007). There was another study showing that survival rate was higher at five years after surgery (61%) compared to those who refused surgery (23%) (Galasko 1995). In general the age at death in patients with or without surgery was highly variable in the case series. Although most deaths could be attributed to respiratory infection, respiratory failure, progressive cardiomyopathy and sudden cardiac death, the cause of death could not be ascertained in many cases. However, the age and causes of death did not seem to differ between patients with or without surgery. Peri-operative mortality is generally uncommon. Most studies reported no peri-operative mortality (Alman 1999; Bellen 1993; Bentley 2001; Bridwell 1999; Brook 1996; Cambridge 1987; Chataigner 1998; Dubousset 1983; Eagle 2007; Galasko 1992; Galasko 1995; Gayet 1999; Hopf 1994; Kennedy 1995; Kinali 2006; LaPrade 1992; Marchesi 1997; Marsh 2003; Matsumura 1997; Mehdian 1989; Miller 1992; Mubarak 1993; Nakazawa 2010; Rice 1998; Rideau 1984; Sakai 1977; Sengupta 2002; Stricker 1996; Sussman 1984; Takaso 2010; Thacker 2002; Weimann 1983), while some studies reported peri-operative mortality ranging from 1.4% to 5% (Modi 2009; Gaine 2004; Cervellati 2004; Granata 1996; Hahn 2008; Harper 2004; Heller 2001; Shapiro 1992).
Outcomes on respiratory function
Galasko found that forced vital capacity could be stabilized for three years and peak expiratory flow rate maintained for up to five years after spinal fusion (Galasko 1992; Galasko 1995). Rideau also found that vital capacity could be maintained static for two years (Rideau 1984); and three participants in Matsumura's study had increased forced vital capacity after operation (Matsumura 1997). Velasco found that the average rate of decline of FVC reduced from 4% per year to 1.75% per year after surgery (Velasco 2007). However, most studies did not demonstrate obvious benefits of scoliosis surgery in terms of respiratory function (Brook 1996; Chataigner 1998; Cervellati 2004; Eagle 2007; Gayet 1999; Granata 1996; Hahn 2008; Kennedy 1995; Kinali 2006; Mehdian 1989; Miller 1988; Miller 1991; Miller 1992; Shapiro 1992; Thacker 2002). While some studies found that patients with poor pre-operative respiratory function fared similarly to those with better respiratory function (Marsh 2003; Harper 2004), other studies suggested that the prognosis was worse in patients with poorer pre-operative respiratory function (Matsumura 1997; Sussman 1984).
Functional outcome and quality of life
In general, previous descriptive studies suggested that surgical correction of scoliosis resulted in better sitting position, quality of life and patient satisfaction (Bentley 2001; Bridwell 1999; Cambridge 1987; Granata 1996; Marchesi 1997; Matsumura 1997; Miller 1991; Miller 1992; Rice 1998; Rideau 1984; Sakai 1977; Shapiro 1992).
Complications of spinal surgery
Severe complications after spinal surgery are not infrequent and occur in up to 68% of patients (Modi 2009). These include cardiac arrest (Bentley 2001), cardiac arrhythmia (Harper 2004), heart block (Galasko 1992), respiratory failure requiring tracheostomy (Chataigner 1998; Galasko 1992; Galasko 1995; Harper 2004; Heller 2001; Marsh 2003) or mechanical ventilation post-operatively (Bentley 2001; Brook 1996; Heller 2001; Modi 2009), massive bleeding (Heller 2001; Modi 2008a), pneumonia (Bentley 2001; Galasko 1992; Harper 2004; Heller 2001; Modi 2009; Rideau 1984), pleural effusion (Harper 2004; Modi 2009), hemothorax or pneumothorax (Bentley 2001; Heller 2001; Modi 2009), spinal cord injury (Modi 2009), colonic perforation (Bentley 2001), bladder dysfunction (Bentley 2001; Hopf 1994), urinary tract infection (Modi 2009), deep wound infection (Arun 2010; Modi 2008a; Modi 2009; Sengupta 2002), infection necessitating removal or revision of surgical implants (Eagle 2007; Heller 2001), failure of implants (Arun 2010; Bentley 2001; Gaine 2004; Stricker 1996), dislodgement or dislocation of implants (Heller 2001; LaPrade 1992; Matsumura 1997), loosening of implants (Arun 2010; Modi 2009; Sengupta 2002), mechanical problems requiring revision surgery (Bentley 2001; Gaine 2004; Gayet 1999; Granata 1996; Sengupta 2002), pseudarthrosis (Gaine 2004; Thacker 2002), bone fracture (Alman 1999), pressure sores (Granata 1996; Modi 2009; Modi 2010), dural leak (LaPrade 1992) and deep vein thrombosis (Heller 2001). Several studies reported that postoperative complications were more frequent in patients with greater severity of scoliosis (Bentley 2001; Sakai 1977; Sussman 1984).
Comparisons of different operative methods
In general, fusion to sacrum does not offer benefits over fusion to a more proximal level (Gaine 2004; Mubarak 1993; Rice 1998; Sengupta 2002), unless scoliosis is severe and pelvic obliquity is significant (Alman 1999; LaPrade 1992; Modi 2010). Although none of the surgical methods was uniformly better than others, Isola system (Gaine 2004) or segmental spinal fusion (Miller 1991; Miller 1992) might achieve better correction of deformity, and intraspinous wiring might result in shorter operative time and less blood loss compared to sublaminar wiring (LaPrade 1992). Pedicle screw system might also result in shorter operative time and less blood loss compared to sublaminar instrumentation system (Arun 2010).
No meta-analysis of these available data was performed because the retrospective non-randomized, uncontrolled studies were observational in nature and were prone to bias and confounding. There is currently an absence of high level evidence supporting scoliosis surgery in patients with Duchenne muscular dystrophy. There is also a lack of evidence for or against a particular modality of surgical approach. Controlled clinical trials with random allocation into treatment and control groups are needed before firm conclusions on the benefits and risks of scoliosis surgery in patient with DMD can be made.
In the absence of evidence it is our view that clinicians might need to consider anecdotal evidence and their personal experience as well as expert opinions as guidance for their decision on the best care for individual patient. Potential benefits on quality of life and functional status as well as risks of morbidity and mortality should be fully discussed with the patients before embarking on surgery for scoliosis. Patients should also be informed about the uncertainty of benefits on long-term survival and respiratory function after scoliosis surgery.
Implications for practice
Since there were no RCTs available to evaluate the effectiveness of scoliosis surgery in people with Duchenne muscular dystrophy, no recommendation can be made for clinical practice.
Implications for research
RCTs are needed to investigate the effectiveness of scoliosis surgery, in terms of patients' satisfaction, quality of life, functional status, respiratory function (forced vital capacity, forced expiratory volume in one second, peak expiratory flow) and survival. It should be feasible to randomize patients into surgery versus non-surgical management. Although placebo control treatment might not be feasible, random allocation of patients into different treatment groups is essential to avoid selection bias and ensure baseline comparability of different groups. Although blinding of patients and clinicians is almost impossible, blinding of outcome assessors is important and probably feasible. Quality of life and functional status should be assessed by validated questionnaires and instruments. The relative benefits and risks of different surgical treatment modalities and different extents of spinal fusion should also be investigated by RCTs. Stratifications by potentially important prognostic factors such as age, baseline respiratory function and severity of scoliosis should be considered.
We wish to thank Sarah Massey and the Illingworth Library at the Sheffield Children's Hospital for their help and support in locating and retrieving studies. We also thank Angela Gunn for updating search strategies and searching various electronic databases.
Editorial support from the Cochrane Neuromuscular Disease Group for an earlier update was funded by the TREAT NMD Network European Union Grant 036825.
The editorial base of the Cochrane Neuromuscular Disease Group is supported by the MRC Centre for Neuromuscular Diseases and the Muscular Dystrophy Campaign.
Data and analyses
This review has no analyses.
Appendix 1. MEDLINE strategy
Database: Ovid MEDLINE(R) <1946 to July Week 3 2012>
1 randomized controlled trial.pt. (332315)
2 controlled clinical trial.pt. (84684)
3 randomized.ab. (235702)
4 placebo.ab. (133040)
5 drug therapy.fs. (1552464)
6 randomly.ab. (169810)
7 trial.ab. (244167)
8 groups.ab. (1114025)
9 or/1-8 (2885687)
10 exp animals/ not humans.sh. (3757814)
11 9 not 10 (2450652)
12 surg$.mp. or surgery/ (1335297)
13 spine$.mp. (82686)
14 spinal.mp. (269459)
15 vertebra$.mp. (166510)
16 or/13-15 (412217)
17 12 and 16 (56524)
18 spinal fusion/ or spinal fusion.mp. (15911)
19 17 or 18 (62847)
20 scolio$.mp. or Scoliosis/ (15574)
21 duchenne.mp. or Muscular Dystrophy, Duchenne/ (7902)
22 11 and 19 and 20 and 21 (18)
23 remove duplicates from 22 (17)
Appendix 2. EMBASE search strategy
Database: Embase <1980 to 2012 Week 30>
1 crossover-procedure.sh. (34521)
2 double-blind procedure.sh. (109963)
3 single-blind procedure.sh. (16165)
4 randomized controlled trial.sh. (326003)
5 (random$ or crossover$ or cross over$ or placebo$ or (doubl$ adj blind$) or allocat$).tw,ot. (885002)
6 trial.ti. (133129)
7 clinical trial/ (869205)
8 or/1-7 (1482353)
9 (animal/ or nonhuman/ or animal experiment/) and human/ (1194751)
10 animal/ or nonanimal/ or animal experiment/ (3291877)
11 10 not 9 (2727149)
12 8 not 11 (1395248)
13 limit 12 to embase (1081020)
14 Surgery/ or surg$.mp. (1965351)
15 (spine or spinal or vertebra$).mp. (474719)
16 14 and 15 (86443)
17 exp Spine Fusion/ (16226)
18 (spinal fusion or spine fusion).mp. (16755)
19 16 or 17 or 18 (92142)
20 exp Scoliosis/ or scoliosis.mp. (20307)
21 Duchenne Muscular Dystrophy/ or duchenne.mp. (11023)
22 13 and 19 and 20 and 21 (11)
Appendix 3. CENTRAL search strategy
#1 MeSH descriptor General Surgery explode all trees
#3 (#1 OR #2)
#4 (spine or spinal or vertebra*)
#5 (#3 AND #4)
#6 MeSH descriptor Spinal Fusion, this term only
#7 spinal fusion or spine fusion
#8 (( #5 AND #6 ) OR #7)
#11(#8 AND #9 AND #10)
Appendix 4. CINAHL search strategy
Tuesday, July 31, 2012 11:29:22 AM
S29 S18 and S28 13
S28 S25 and S26 and S27 35
S27 ("scoliosis") or (MH "Scoliosis") 3652
S26 ("duchenne") or (MH "Duchenne Muscular Dystrophy") 793
S25 S22 or S24 13207
S24 S23 or spinal fusion or spine fusion 3727
S23 (MH "Spinal Fusion") 3397
S22 S20 and S21 12713
S21 spine or spinal or vertebra* 53209
S20 S19 or surgery 216179
S19 (MH "Surgery, Operative") 12808
S18 S1 or S2 or S3 or S4 or S5 or S6 or S7 or S8 or S9 or S10 or S11 or S12 or S13 or S14 or S15 or S16 or S17 550602
S17 ABAB design* 77
S16 TI random* or AB random* 111997
S15 ( TI (cross?over or placebo* or control* or factorial or sham? or dummy) ) or ( AB (cross?over or placebo* or control* or factorial or sham? or dummy) ) 231348
S14 ( TI (clin* or intervention* or compar* or experiment* or preventive or therapeutic) or AB (clin* or intervention* or compar* or experiment* or preventive or therapeutic) ) and ( TI (trial*) or AB (trial*) ) 78188
S13 ( TI (meta?analys* or systematic review*) ) or ( AB (meta?analys* or systematic review*) ) 22863
S12 ( TI (single* or doubl* or tripl* or trebl*) or AB (single* or doubl* or tripl* or trebl*) ) and ( TI (blind* or mask*) or AB (blind* or mask*) ) 18252
S11 PT ("clinical trial" or "systematic review") 103252
S10 (MH "Factorial Design") 835
S9 (MH "Concurrent Prospective Studies") or (MH "Prospective Studies") 182671
S8 (MH "Meta Analysis") 14368
S7 (MH "Solomon Four-Group Design") or (MH "Static Group Comparison") 30
S6 (MH "Quasi-Experimental Studies") 5485
S5 (MH "Placebos") 7634
S4 (MH "Double-Blind Studies") or (MH "Triple-Blind Studies") 24614
S3 (MH "Clinical Trials+") 144869
S2 (MH "Crossover Design") 9471
S1 (MH "Random Assignment") or (MH "Random Sample") or (MH "Simple Random Sample") or (MH "Stratified Random Sample") or (MH "Systematic Random Sample") 57405
Appendix 5. Proquest Dissertation & Thesis Database search strategy
Duchenne and surgery and scoliosis
Appendix 6. NIH Clinical Trials Database
Duchenne and surgery and scoliosis
Last assessed as up-to-date: 31 July 2012.
Protocol first published: Issue 3, 2005
Review first published: Issue 1, 2007
Contributions of authors
Cheuk DKL: protocol development, searching for trials, quality assessment of trials, data extraction, data input, data analyses, development of final review, corresponding author.
Wong V: protocol development, searching for trials, quality assessment of trials, data extraction, data analyses, development of final review.
Wraige E: protocol development, searching for trials, quality assessment of trials, data extraction, data analyses, development of final review.
Baxter P: protocol development, searching for trials, quality assessment of trials, data extraction, data analyses, development of final review.
Cole A: protocol development, searching for trials, quality assessment of trials, data extraction, data analyses, development of final review.
Declarations of interest
No potential conflict of interest is known.
Sources of support
- None, Not specified.
- None, Not specified.
Differences between protocol and review
Risk of bias methodology updated in accordance with the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2011).
Change in authorship: we were unable to contact original authors N'Diaye T and Mayowe V for this update.
Medical Subject Headings (MeSH)
MeSH check words