Aims

Whether a combined anteroposterior fusion or a posterior-only fusion is more effective in the management of patients with Scheuermann’s kyphosis remains controversial. The aim of this study was to compare the radiological and clinical outcomes of these surgical approaches, and to evaluate the postoperative complications with the hypothesis that proximal junctional kyphosis would be more common in one-stage posterior-only fusion.

Scoliosis surgery has moved towards all posterior correction, as modern implants are perceived to be powerful enough to overcome stiffer and more severe curves. However, shortening of the anterior spinal column remains most effective in creating thoracic kyphosis, and may still have a role in correcting both coronal and sagittal deformities. Furthermore, anterior correction of lumbar and thoracolumbar curves can theoretically reduce the distal fusion level, and may have significant impact on patients' post-operative function.

A single surgeon series of 62 patients with idiopathic scoliosis were examined retrospectively. Radiographs and operation notes were examined by 2 spinal surgeons, sagittal and coronal parameters were measured before and after the operation. The patients were divided into 4 groups: 16 anterior and posterior fusions (AP), 16 anterior thoracolumbar fusions (A), 5 anterior thoracic releases and posterior fusions (AR), and 25 posterior fusions only (P).

The mean age was 15.3 (range 10 – 20). The mean main thoracic Cobb angle pre-operatively was: 54° (AP), 43° (A), 63° (AR), and 50° (P). The mean thoracolumbar Cobb angle was: 55° (AP) and 51° (A). There was no significant difference in lumbar lordosis.

The mean post-operative main thoracic Cobb angle was: 9° (AP), 13° (A), 9° (AR) and 15° (P). There was significant difference between AR and P groups. The mean post-operative thoracolumbar Cobb angle was: 8° (AP) and 6° for (A). There was a significant difference in the post-operative thoracic kyphosis between AP (mean 14°), A (mean 38°), AR (mean 19°) and P (mean 14°). Overall, the lumbar lordosis for all 4 groups reduced from a mean of 67° to 50°, with no significant difference between the groups.

The distal level of fusion for A and AP groups were L3 for all cases, whereas 2 cases had to extend to L4 in the P group.

Anterior release improved both coronal and sagittal correction when compared to posterior only surgery, however it is of unknown clinical significance. Anterior thoracolumbar fusion with or without posterior spinal fusion appeared to produce adequate coronal correction if fused to L3. No difference was found between all groups in post-operative lumbar lordosis.

There is a wide range of reports on the prevalence of neurological injuries during scoliosis surgery, however this should depend on the subtypes and severity of the deformity. Furthermore, anterior versus posterior corrections pose different stresses to the spine, further quantifications of neurological risks are presented.

Neuromonitoring data was prospectively entered, and the database between 2006 and 2012 was interrogated. All deformity cases under the age of 21 were included. Tumour, fracture, infection and revision cases were excluded.

All “red alerts” were identified and detailed examinations of the neuromonitoring records, clinical notes and radiographs were made. Diagnosis, deformity severity and operative details were recorded.

2290 deformity operations were performed: 2068 scoliosis (1636 idiopathic, 204 neuromuscular, 216 syndromic, and 12 others), 89 kyphosis, 54 growing rod procedures, and 80 operations for hemivertebra. 696 anterior and 1363 posterior operations were performed for scoliosis (8 not recorded), and 38 anterior and 51 posterior kyphosis correction.

67 “red alerts” were identified, there were 14 transient and 6 permanent neurological injuries. 62 were during posterior stage (24 idiopathic, 21 neuromuscular, 15 syndromic (2 kyphosis), 1 growing rod procedure, 1 haemivertebra), and 5 were during anterior stage (4 idiopathic scoliosis and 1 syndromic kyphosis). Average Cobb angle was 88°. 1 permanent injuries were during correction for kyphosis, and 5 were for scoliosis (4 syndromic, 1 neuromuscular, and 1 anterior idiopathic).

Common reactions after “red alerts” were surgical pause with anaesthetic interventions (n=39) and the Stagnara wake-up test (n=22). Metalwork was partially removed in 20, revised in 12 and completely removed in 9. 13 procedures were abandoned.

The overall risk of permanent neurological injuries was 0.2%, the highest risk groups were posterior corrections for kyphosis and scoliosis associated with a syndrome. 4% of all posterior deformity corrections had “red alerts”, and 0.3% resulted in permanent injuries; compared to 0.6% “red alerts” and 0.3% permanent injuries for anterior surgery. The overall risk for idiopathic scoliosis was 0.06%.

Introduction

Pedicle subtraction osteotomy is a powerful technique for correcting sagittal imbalance in ankylosing spondylitis. There has been significant perioperative morbidity associated with this technique in the peer review literature. We present the Royal National Orthopaedic Hospital experience with a single surgeon retrospective study that was conducted to evaluate the outcomes in patients who underwent lumbar pedicle subtraction osteotomy for the correction of thoracolumbar kyphotic deformity in ankylosing spondylitis.

Scoliosis and hip subluxation/dislocation are common and often coexistent problems encountered in patients with cerebral palsy (CP). The underlying mechanism may be related to muscle imbalance. Surgical correction may become necessary in severe symptomatic cases. The effect of surgical correction of one deformity on the other is not well understood.

We retrospectively reviewed a series of 17 patients with total body cerebral palsy with diagnoses of both scoliosis and hip subluxation who had undergone either surgical correction of their scoliosis (9 patients) or a hip reconstruction to correct hip deformity (8 patients). In all patients, the degree of progression of both deformities was measured, radiographically, using the Cobb angle for the spine and the percentage migration index for hip centre of rotation at intervals before and at least 18 months post surgery.

All patients who underwent scoliosis correction had a progressive increase in the percentage of hip migration at a rate greater than that prior to scoliosis surgery. Similarly, patients who underwent a hip reconstruction procedure demonstrated a more rapid increase in their spine Cobb angles post surgery.

There may be a relationship between hip subluxation/dislocation and scoliosis in CP patients. Surgery for either scoliosis or hip dysplasia may in the presence of both conditions lead to a significant and rapid worsening of the other. The possible negative implications on the overall functional outcome of the surgical procedure warrants careful consideration to both hip and the spine before and after surgical correction of either deformity. In selected cases there may be an indication for one procedure to follow soon after the other.

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.

Introduction: The aim of this study is to compare the efficacy of the AO Universal Spine System (AO USS) with Harrington-Luque instrumentation for the treatment of King type II idiopathic scoliosis.

Methods/Results: A retrospective analysis was performed on two groups of patients with King II adolescent idiopathic scoliosis. The first group consisted of 40 consecutive patients treated with Harrington-Luque instrumentation between 1990 and 1993. The second group consisted of 25 consecutive patients treated with AO USS instrumentation between 1994 and 1996. The groups were well matched with respect to age, sex and curve severity. Inclusion criteria were patients over the age of 12 years with a King II curve pattern and a Cobb angle of greater than 40°. Half of the patients in each group underwent anterior release prior to posterior fusion. All patients were followed up six monthly for 18 months. The thoracic curve, lumbar curve, kyphosis and lordosis were measured using the Cobb method.

The mean pre-operative thoracic and lumbar curves were 62° and 43.9° respectively in the Harrington group and 57.5° and 35.9° in the AO USS group. On average 11.4 levels were fused in the Harrington group compared to 10.9 levels in the AO USS group. The mean post-operative correction of the thoracic curve in the AO USS group of 64% was significantly greater than the 51% achieved in the Harrington group (p< 0.005). At 18 months there was a 7% loss of correction in the Harrington group and 9% in the AO USS group. The correction of lumbar curve of 41% in the Harrington group and 46% in the AO USS group at 18 months was not significantly different. In the sagittal plane the AO USS group had significantly better preservation of the lumbar lordosis but there was no difference in kyphosis correction. Blood loss was similar in both groups. Mean operative time of 132 minutes in the AO USS group was shorter than the mean time of 153 minutes in the Harrington group (p< 0.05). Two hooks in the Harrington group became dislodged and two in the AO group. There were no neurological complications in either group. All the patients in both groups achieved a solid fusion.

Conclusion: AO USS is a safe and effective instrumentation system for the treatment of King type II adolescent idiopathic scoliosis. Correction of the thoracic curve is superior to that achieved with Harrington-Luque instrumentation and operative time is shorter. AO USS enables better preservation of the lumbar lordosis than Harrington-Luque. There is no difference in blood loss, complication rate and fusion rates between the two techniques. It has become our instrumentation system of choice for this group of patients.

Fourteen patients with neurofibromatosis presented with symptoms or radiological evidence of cervical spine involvement over a period of 27 years. The symptoms included neurological deficit in five, neck mass in two, deformity in eight, decrease in neck movement in two and two with neck pain. Patients’ age ranged from five to forty-two years. Twelve patients have had surgical procedures. Two patients have been followed up and treated non-operatively despite osteolysis of vertebral bodies with kyphosis of more than 100°.

Current literature presents few cases of neurofibromatosis of the cervical spine. The largest World Series is of eight cases (Craig and Govender et al 1992). At present there is no coherent strategy of management for these conditions. The authors of this series recommend that correcting spinal deformity or to stabilise an unstable spine requires combined anterior and posterior fusion. Posterior fusion alone has a higher failure rate. Surgery for severe kyphotic deformity is questionable especially with no neurological deficit.