This study assessed whether spinal fusion surgery could be performed safely in patients with Duchenne’s muscular dystrophy (DMD) and a low (less than 30%) predicted forced vital capacity (PFVC).

Patients were identified with a diagnosis of scoliosis secondary to DMD who underwent spinal fusion procedures at the Royal National Orthopaedic Hospital, Stanmore between January 1990 and December 1999. Their notes and radiographs were reviewed and a standardised data collection form was completed.

Thirty patients with a mean age of 14 years 8 months at surgery underwent posterior spinal fusions. All were discharged from hospital alive and self-ventilating on average 22 days post-operatively (range 13–62 days). Thirteen patients had a PFVC less than 30%. The mean pre-operative curve was 61 degrees (range 30 to 90) and the mean number of levels fused was 15 (i.e. T3 to sacrum). The mean correction was 36 degrees (range 16 to 61). Two patients required temporary tracheotomies, one with a PFVC of 34% and one with a PFVC of 20%. Both were removed successfully after 39 days and 27 days respectively. There was no association between PFVC and operative time, blood loss, length of time on ventilatory support, time intubated, incidence of complications or length of admission.

Historically, only curves of greater than 20–35 degrees have been considered suitable for surgery, as the progression of the curve is associated with a marked decline in respiratory function. Considering the currently used criteria for surgery, the group of 13 with low PFVCs normally would have been denied surgery.

We conclude that spinal fusion surgery can be safely performed in DMD patients with a low PFVC.

Background: There are conflicting reports regarding the effect of scoliosis surgery on respiratory function in Duchenne Muscular Dystrophy (DMD)^1,2. Galasko et al² found that the Percentage Predicted Forced Vital Capacity (%PFVC), remained static for thirty six months following surgery, in patients with DMD that underwent spinal stabilisation for scoliosis. The aim of the current study was to support or refute the above finding in a large series of patients with DMD.

Methods: A retrospective analysis of data on 55 consecutive patients with DMD that underwent single stage posterior surgical correction for scoliosis. We analysed the data of 55 boys with DMD who underwent scoliosis surgery between 1990 and 2002. Age at surgery, pre-operative Cobb angles, pre-operative %PFVC, and post-operative %PFVC at 6 months, 12-18 months and 2–3 years were collected. We documented the pre-operative Cobb angle ± SD to assess the difficulty level of our surgical cases. Percentage PFVC was used as our outcome measure to assess respiratory function. The mean pre-operative %PFVC was compared to the post –operative mean %PFVC at three different time intervals; at 6 months, 12 to 18 months and at 2 to 3 years.

Results: The mean age was 14.6 years (range 11.2–18yrs). The mean pre-operative Cobb angle was 65.4 degrees ± 14.8. The mean %PFVC pre-operatively was 33.9 ± 10.4. The mean post-operative %PFVC’s were: 6 months (29.1 ± 10.4), 12 to 18 months (27.6 ± 12.1) and 2 to 3 years (25.4 ± 8.7). Therefore the mean % PFVC following surgery at 6 months, 12 to 18 months and 2 to 3 years decreased from the mean pre-operative % PFVC by 4.8%, 6.3% and 8.5% respectively.

Conclusion: The natural history of patients with DMD is a gradual decline in respiratory function. In the current study the mean post –operative %PFVC was less than the mean pre-operative %PFVC at 6 months, 12 to 18 months and at 2 to 3 years post surgery. Our series would suggest that respiratory function declines post-operatively, even in the short term, in patients with DMD that undergo spinal stabilisation. The decline in respiratory function in our study was progressive over the 3 year follow up period.

Background: The long term survival of patients with type II and III spinal muscular atrophy differs considerably from patients with Duchenne muscular dystrophy. Despite this, treatment of scoliosis in both groups is often reported together¹. There are only sporadic reports, all with small numbers, of combined anterior and posterior (two stage) scoliosis surgery in patients with spinal muscular atrophy (SMA)¹. The aim of the current study was to document the peri-operative morbidity, length of stay and correction of deformity in patients with SMA that had two stage surgery and compare them with the patients that had single stage surgery.

Methods: A retrospective analysis of data on our consecutive series of patients with SMA.

We analysed the data of 31 patients with SMA (16M:15F) who underwent scoliosis surgery between 1996 and 2004. The data collected included SMA type, age at surgery, percentage predicted forced vital capacity(%PFVC), blood loss, duration of surgery, complications, type of surgery undertaken, pre-operative mean Cobb angle ± SD(including bending film Cobb angle ± SD), post-operative Cobb angle ± SD and length of hospital stay. The decision to do single or two stage surgery was based on the history of recurrent chest infection, %PFVC and the stiffness of the curve. Percentage correction of Cobb angle in patients that had two stage surgery compared with those that had single stage posterior surgery. Comparison of post-operative respiratory complications, estimated blood loss, total hours in theatre and mean length of stay between the two groups.

Results: There were 27 SMA type II and 4 SMA type III’s with a mean age at surgery of12.5 years (range 7.8 – 17.4). The mean pre-operative Cobb angle of all 31 patients was 89.7° ± 19.7°, the mean bending preoperative Cobb angle was 54° ± 13.3° and the mean post-operative Cobb angle was 33.7° ± 17.3°. Eighteen patients had single stage surgery and 13 had two stage surgery. Twelve out of the thirteen two stage operations had either a thoracotomy or a thoracoabdominal approach. In the patients that had single stage posterior surgery, the mean bending preoperative Cobb angle was 54° ± 13.3° and the mean post-operative Cobb angle was 38.7° ± 19.2°. In the patients that had two stage surgery the mean pre-operative bending Cobb angle was 53.6° ± 11.6° and the post-operative Cobb angle was 25.5° ± 10.8°. The %PFVC in the patients that had single stage and two stage surgery was 39.2 ± 12.8 and 69.2 ± 12.2 respectively. There were 3 respiratory complications in the single stage group and 4 in the two stage group. The average total estimated blood loss (EBL) in the single stage and two stage groups (first and second stage EBL’s combined) were 2433ml and 1902ml respectively. The length of stay for the patients with single stage surgery and two stage surgery was 14.1 ± 4.1 and 18.5 ± 7.4 days respectively. The total surgical hours for the patients with single and two stage surgery were 2.9 ± .6 hrs and 4.8 ± 1.2 hrs respectively.

Conclusion: The results of our series would suggest that in a selected group of SMA patients (no history of recurrent chest infection and an acceptable %PFVC) a better immediate deformity correction can be attained with two stage surgery. This has to be weighed up with a greater total EBL and mean length of stay for the patients that had two stage surgery.

Introduction and Aims: This study is to assess whether spinal fusion surgery can be performed safely in patients with Duchenne’s muscular dystrophy (DMD) and a low (less than 30%) predicted forced vital capacity (PFVC).

Method: Patients were identified with a diagnosis of scoliosis secondary to DMD who underwent spinal fusion procedures at the Royal National Orthopaedic Hospital, Stanmore between January 1990 and December 1999. Their notes and radiographs were reviewed and a standardised data collection form was completed.

Results: Thirty patients with a mean age of 14 years 8 months at surgery underwent posterior spinal fusions. All were discharged from hospital alive and self-ventilating on average 22 days post-operatively (range 13–62 days). Thirteen patients had a PFVC less than 30%. The mean pre-operative curve was 61 degrees (range 30–90) and the mean number of levels fused was 15 (i.e. T3 to sacrum). The mean correction was 36 degrees (range 16–61). Two patients required temporary tracheotomies, one with a PFVC of 34% and one with a PFVC of 20%. Both were removed successfully after 39 days and 27 days respectively. There was no association between PFVC and operative time, blood loss, length of time on ventilatory support, time intubated, incidence of complications or length of admission.

Conclusion: Historically, only curves of greater than 20–350 have been considered suitable for surgery, as the progression of the curve is associated with a marked decline in respiratory function. Considering the currently used criteria for surgery, the group of 13 with low PFVCs normally would have been denied surgery. We conclude that spinal fusion surgery can be safely performed in DMD patients with a low PFVC.

Aim: This study is to assess whether spinal fusion surgery can be performed safely in patients with Duchenne’s muscular dystrophy (DMD) and a low (less than 30%) predicted forced vital capacity (PFVC).

Patients- Methods: Patients were identified with a diagnosis of scoliosis secondary to DMD who underwent spinal fusion procedures at the Royal National Orthopaedic Hospital, Stanmore between January 1990 and December 1999. Their notes and radiographs were reviewed and a standardised data collection form was completed.

Results: Thirty patients with a mean age of 14 years 8 months at surgery underwent posterior spinal fusions. All were discharged from hospital alive and self-ventilating on average 22 days postoperatively (range 13–62 days). Thirteen patients had a PFVC less than 30%. The mean preoperative curve was 61 degrees (range 30 to 90) and the mean number of levels fused was 15 (i.e. T3 to sacrum). The mean correction was 36 degrees (range 16 to 61). Two patients required temporary tracheotomies, one with a PFVC of 34% and one with a PFVC of 20%. Both were removed successfully after 39 days and 27 days respectively. There was no association between PFVC and operative time, blood loss, length of time on ventilatory support, time intubated, incidence of complications or length of admission.

Conslusion: Historically, only curves of greater than 20–350 have been considered suitable for surgery, as the progression of the curve is associated with a marked decline in respiratory function. Considering the currently used criteria for surgery, the group of 13 with low PFVCs normally would have been denied surgery. We conclude that spinal fusion surgery can be safely performed in DMD patients with a low PFVC.