Aim:

To Determine Whether Maximal Rib Prominence Measured On Lateral Radiographs Can Be Used As A Surrogate To Rib Rotation Determined By Surface Tomography (Quantecscanning) In Assessment Of Spinal Rotation.

Introduction

There are controversies in the literature about thoracoplasty and its effect on lung function changes. The aim of the study was to evaluate the effect and outcome of thoracoplasty in conjunction with pedicle screw construct in the treatment of thoracic adolescent idiopathic scoliosis on lung functions.

Study Design

An observational study in patients with congenital spinal deformity.

Patients with peripheral primary bone tumours are often identified and referred at an early stage to a regional tumour service according to established guidelines. In patients with primary bone tumours of the spine, however, the definitive management or outcome of such patients is being prejudiced by preliminary intervention from non-specialist services prior to their referral.

Objective: To audit the standards of management of patients with primary bone tumours of the spine referred to a regional tumour service.

Retrospective review of case notes and radiology.

Subjects: Patients with primary bone tumour of the spine managed at the Orthopaedic Spine Unit with the Regional Bone Tumour Service in Newcastle Upon Tyne Hospitals NHS Trust.

Referral to tumour service, prior intervention, operative treatment, survival, factors affecting definitive management

31 of 39 (16 benign, 23 malignant) patients were initially referred from primary care to services other than the regional tumour service, most commonly neurosurgery (11/39) and paediatric oncology (4/39). Seven of 39 of these patients had undergone interventions prior to their referral to the tumour service, which may have negatively impacted their definitive management or curative surgery.

These tumours present complex issues regarding their definitive management to optimise outcome. Closer links between departments are required to enable the multidisciplinary management of primary bone tumours of the spine. Prior surgical intervention may compromise cure. Those involved in their management should be encouraged to liaise with their regional bone tumour service to improve outcome.

Following the implementation of the Ionising Radiations (Medical Exposure) Regulations Act 2000 and recommendation from International Commission on Radiological Protection (ICRP), the establishment of diagnostic reference levels (DRLs) for all radiological examinations became mandatory. There are no recommended or published standards or national dosage guidelines in the UK of diagnostic reference levels available for fluoroscopy-guided diagnostic and therapeutic spinal procedures. The aim of this study is to establish reference dose area product (DAP) levels for the diagnostic spinal procedures requiring fluoroscopy as a basis for setting DRLs.

All patient data consisted of diagnostic spinal procedures done in 2009 at Newcastle General Hospital under care of 4 spinal surgeons. Radiation data were collected on specific type of the procedure, DAP and screening time. Nerve root blocks, facet joint blocks and facet joint rhizolysis were included for data collection and analysis for this study. The third-quartile values were used to establish the DRLs.

There were 387 nerve root blocks with a mean exposure per injection 171.3 cGycm² (range, 3.0 to 2029.1; third quartile 209.4). Facet joint injections were 669 at a mean radiation dose 41.3 cGycm² (range, 1.9 to 541.0; third quartile 48.9). In a total 430 facet joint rhizolysis, the mean exposure was 44.4 cGycm² (range, 7.7 to 154.5; third quartile 58.4). The mean screening times were 36.7s (range, 0.4-281s; third quartile 41s) for nerve root blocks, mean 11.2s (range, 1.8-37s, third quartile 13.3s) for single facet joint block and mean 14.6s (range, 0.1-162s, third quartile 15.1s) for single facet rhizolysis.

We found the third-quartile values for setting DRLs for single level nerve root block, single facet joint block and single facet joint rhizolysis to be 209.4, 48.9 and 58.4 cGycm² respectively. We recommend that all spinal units in the UK should establish their own local DRLs to help in establishing national dosage guidelines for fluoroscopy-guided diagnostic and also therapeutic spinal procedures.

The Walter Reed Visual Assessment Scale (WRVAS) is a valid and reliable tool, designed to measure physical deformity as perceived by patients with idiopathic scoliosis. It is unclear whether the type of treatment in patients with thoracic adolescent idiopathic scoliosis affects the patients' perception of cosmesis gain. We studied 40 patients with Adolescent Idiopathic Scoliosis treated with posterior spinal fusion with (20) and without thoracoplasty (20) aiming to assess correlation of improvement in radiological parameters to subjective cosmesis gain.

Patients with Adolescent Idiopathic Scoliosis treated with posterior spinal fusion with thoracoplasty (20) and without thoracoplasty (20) filled out Walter Reed Visual Assessment Scale (WRVAS) forms with their perception of deformity before and after operation at the clinic follow-up. The WRVAS forms include seven aspects of the deformity i.e. spinal deformity, rib prominence, lumbar prominence, thoracic deformity, trunk imbalance, shoulder asymmetry and scapular asymmetry. Each aspect is shown with five figures of increasing severity of the deformity and scored from minimum (1) to maximum (5). Results are presented as the sum of the seven questions. The lowest possible score for the total is 7, while the highest possible total score is 35. The curve magnitude was divided into 5 subgroups as 30 and under, 30-40, 40-50, 50-60 and 70 and over.

Floor and ceiling effects were analysed as percentage of cases with minimum and maximum scores.

Our study confirmed that following posterior scoliosis surgery with and without thoracoplasty, there was significant improvement in perceived appearance. Overall spinal deformity and thoracic deformity correction were comparable in two groups. However, improvement in rib hump prominence, flank prominence, restoration of truncal, shoulder and scapular symmetry were much better rated by the patients with PSF and thoracoplasty group using Walter Reed Visual Assessment Scale.

Proponents of thoracoplasty suggest a better correction, obviating iliac crest donor site morbidity, obtaining bone grafts for fusion and better rib hump correction. Opponents suggest increase risk for chest complications, additional operating time and blood loss, and possible longer hospital stay. There are controversies in the literature about thoracoplasty and its effect on lung function changes. The aim of the study was to evaluate the effect and outcome of thoracoplasty in conjunction with pedicle screw construct in the treatment of thoracic adolescent idiopathic scoliosis on lung functions.

It is a retrospective study of consecutive series of 62 patients with thoracic adolescent idiopathic scoliosis surgically treated by single surgeon between 2007 and 2008 at a tertiary referral Orthopaedic Spinal unit. Posterior spinal fusion and thoracoplasty (n=32, all but one girls) were compared with 30 without thoracoplasty (all but one girls). Clinical and radiographic analysis was performed, including the SRS-30 questionnaire and Pulmonary Function Tests (PFT). Absolute and percent-predicted values of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and total lung capacity (TLC) were evaluated preoperatively and at 3-months, 1 year and/or 2-year follow-up, and comparisons were made between two groups. The minimum follow-up was one year.

No statistical differences were found between the two groups in PFT's both pre-operatively and at latest follow up ranging 1 to 3 years. Our findings suggest that thoracoplasty did not adversely affected long-term PFT's in AIS patients compared to patients treated by posterior spinal fusion alone. Three-month postoperative pulmonary function test values in both groups experienced 15-30% decline which returned to the preoperative baseline at 1 year in > 90% patients. In thoracoplasty group, 5 to 8 ribs were resected and used for bone graft. Chest complications were observed in 2 patients requiring chest drainage. Prolonged donor site morbidity was noted in 3 patients.

Thoracoplasty showed comparable clinical and radiological correction without any significant pulmonary function compromise. Pulmonary function test values returned to the preoperative baseline at 1 year in > 90% patients.

Background: Although needle tip position has been correlated with outcome with respect to pain relief, and to complication rate, to our knowledge, no previous study assesses the location of the needle tip with respect to its ability to isolate injectate around the exiting nerve root without blocking the traversing nerve root to the next caudal level.

Aim: To study the location of injectate when diagnostic selective nerve root blockade is performed.

Method: 87 consecutive selective nerve root blocks performed by a single surgeon were assessed. A consistent surgical technique was utilised. Antero-Posterior fluoroscopy films were analysed to determine the location of injectate in relation to the foraminal and pedicle anatomy. A pro-forma operation note ensured all necessary data was collected prospectively.

Results: Of needle tips positioned lateral to the middle third of the superior pedicle on the AP view, 45 of 51 flowed into the nerve sheath alone, and 6 flowed into both the nerve sheath, and spinal canal. Of these 6, 2 were due to a larger volume of contrast injected, and 2 were due to abnormal anatomy from marked lumbar degenerative scoliosis. Of tips located below the middle third of the pedicle, 2 of 29 flowed into the nerve sheath alone, 2 flowed into the canal alone, and 27 flowed into both. Of those placed medial to zone below the middle third of the pedicle, all seven flowed into the canal only. Analysis using Fisher’s Exact test yielded an extremely statistically significant result, with p < 0.001 comparing needle tip positions in the lateral position with the mid-zone and medial tip positions, and their relationship with injectate reaching the traversing nerve root.

Discussion: For a nerve root block to be truly selective, no injectate must flow past the exiting root to the traversing root. Low volumes of injectate must be placed predictably and accurately. This paper demonstrates the importance of needle tip location in preventing flow beyond the foramen. It is also recommended that contrast be used when significant deformity is present. In cases where there is a therapeutic rather than diagnostic intention, such accuracy is unnecessary. This study does not address the efficacy of the selective nerve root block as a non-operative intervention, nor does it assess the ability of the block to predict operative benefit. It does, however, provide a benchmark for accuracy achievable in patients without significant spinal deformity.

Conclusion: Care must be taken to ensure that the needle tip is positioned lateral to the zone below the middle third of the pedicle if a selective nerve root block is to be used for diagnostic purposes, particularly if there is significant deformity or no contrast is used. In the absence of deformity, however, selective nerve root block may be performed reliably, with a location accuracy of 96%.

Purpose of Study: Literature suggests that decompression of Chiari malformation for syrinx may influence the need for surgical correction of scoliosis: we therefore wished to review the clinical presentation, indications for surgery, complications and requirement for scoliosis correction after foramen magnum decompression in patients with syrinx, secondary to Chiari malformation.

Methods: A retrospective review of the available clinical information including clinic letters, case notes and radiology.

Results: 9 patients were identified. (Age range 4–16) 8 patients had progressive curves.

Neurological symptoms: 2 patients significant, 4 insignificant, 3 none.

Of 9 patients, 1 has not had surgery.

8 patients have had foramen magnum decompressions (+/− laminectomy, +/− duroplasty).

Complications: 1 patient required revision surgery for a radiculopathy > 1year post first operation: this patient required prolonged ventilation for MRSA chest sepsis. 1 patient developed a symptomatic pseudomeningocoele requiring lumbar drainage. All patients had improvement of neurological symptoms.

Of 8 patients having a foramen magnum decompression, 5 required scoliosis correction and 3 did not.

Conclusions: Foramen magnum decompression can relieve neurological symptoms in this cohort of patients.3 of 8 (38%) patients avoided scoliosis correction after decompression and decompression may therefore influence curve progression.

Ethics approval: Not applicable

Interest Statement: None

Introduction: Sniff nasal inspiratory pressure has become a valuable tool in assessing respiratory muscle weakness. Its role in the scoliosis population is still being defined.

Aim: To assess significance of Sniff nasal inspiratory pressure in paediatric patients with scoliosis. Eighty-nine paediatric patients were investigated with SNIP at the time of preoperative assessment for scoliosis surgery from Jan, 2000 to Dec, 2006. Patients were divided into neuromuscular(24) and idiopathic(55). Other causes and revision were excluded(10). SNIP was evaluated with respect to curve pattern and curve degree. This included radiograph and case note review.

The mean SNIP value for the idiopathic and neuromuscular groups was 70cmH2O and 44cmH2O respectively. This was significantly different (P=0.006). The mean cobb angle for idiopathic pattern was 58°. For the neuromuscular group it was 73°. There was no correlation between SNIP value and curve severity in either the idiopathic or neuromuscular group.

SNIP value does not correlate with cobb angle severity. SNIP can differentiate idiopathic from neuromuscular scoliosis. Low SNIP values are found in neuromuscular scoliosis. Its role in non neuromuscular scoliosis does not appear to be significant.

Aim: To study the location of injectate when diagnostic selective nerve root blockade is performed.

Method: 87 consecutive selective nerve root blocks performed by a single surgeon were assessed. A consistent surgical technique was utilised for all patients. Antero-Posterior fluoroscopy films were analysed to determine the location of injectate in relation to the foraminal and pedicle anatomy.

Results: Of needle tips positioned lateral to the middle third of the superior pedicle on the AP view, 45 of 51 flowed into the nerve sheath alone, and 6 flowed into both the nerve sheath, and spinal canal. Of these 6, 2 were due to a larger volume of contrast injected, and 2 were due to abnormal anatomy from marked lumbar degenerative scoliosis. Of needle tips located below the middle third of the pedicle, 2 of 29 flowed into the nerve sheath alone, 2 flowed into the canal alone, and 27 flowed into both. Of those placed medial to zone below the middle third of the pedicle, all seven flowed into the canal only.

Conclusion: Care must be taken to ensure that the needle tip is positioned lateral to the zone below the middle third of the pedicle if a selective nerve root block is to be used for diagnostic purposes, particularly if there is significant deformity or no contrast is used. In the absence of deformity, however, selective nerve root block may be performed reliably, with a location accuracy of 96% providing the tip of the needle lies in the lateral position described.

Background: Sniff nasal inspiratory pressure (SNIP) has become a valuable tool in assessing respiratory muscle weakness. Its role in the scoliosis population is still being defined.

Purpose: To assess significance of Sniff nasal inspiratory pressure value in paediatric patients with scoliosis.

Methods: Eighty-nine paediatric patients were investigated with SNIP at the time of preoperative assessment for scoliosis surgery from Jan, 2000 to Dec, 2006. Patients were divided into neuromuscular (24) and idiopathic (55). Other causes and revision were excluded (10). SNIP was evaluated with respect to curve pattern and curve degree. This included radiograph and case note review.

Results: The mean SNIP value for the idiopathic and neuromuscular groups was 70cmH2O and 44cmH2O respectively. This was statistically significantly different (0.006). The mean cobb angle for idiopathic pattern was 58 degree. For the neuromuscular group it was 73 degree. There was no correlation between SNIP value and curve severity in either the idiopathic or neuromuscular group.

Conclusion: SNIP is a valuable test when used in conjunction with vital capacity and overnight oxygen saturation, height, comorbidities in the neuromuscular population. It is a sensitive indicator of respiratory muscle weakness. It does not appear to reflect increasing curve severity. It does not appear relevant in scoliosis without a neuromuscular disorder.

Significance: SNIP combined with vital capacity, overnight oxygen saturation, height and co morbidities can be used to assess severity of neuromuscular scoliosis. SNIP value alone has little relevance.

Aim: We present a new trunk asymmetry index for topographic measurement of patients with thoracolumbar scoliosis, which does not require full 3-dimensional reconstruction of the back shape and can be performed with a digital camera and a laptop.

Material and methods: To date, 27 patients were assessed preoperatively, and 14 of these also had post operative assessments. The midline was identified between the two lateral edges of the trunk visible on a digital photograph. This was compared with a straight line. We derived an asymmetry index for each image and compared this with the cobb angle on x-rays pre- and postoperatively.

Results: The new asymmetry index correlated well with the cobb angle up to about 50°. Curves beyond this tended to have compensatory curves. This made interpretation more complex, however, if the compensatory cobb angle was subtracted from the major cobb angle, the asymmetry index fell at the expected points. It clearly distinguishes pre-operative and post-operative images. With POTSI, (posterior trunk symmetry index) there is a significant difference between the pre- and post-operative groups and significant overlap of the two distributions.

Conclusions: Surface topography of scoliotic patients is a useful tool to assess the progression of scoliosis without X-rays, reducing radiation exposure. The proposed new index is a promising measurement for monitoring the progress of a thoracolumbar curve with much better sensitivity and specificity than existing topographic indices, without requiring the capital outlay for surface topography equipment as it can be obtained from a simple digtal photograph and laptop.

Study Design: A prospective observational study of scoliosis patients who were on non-invasive 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.

Subjects: 9 patients (6 males, 3 females) with scoliosis and respiratory failure. The mean age at surgery was 12.4years (range 8–16yrs). There were 4 patients with multicore myopathy, 2 with merocin negative congenital muscular dystrophy, 1 with Ullrichs muscular dystrophy, 1 patient with congenital AcylCOA dehyrogenase deficiency and 1 with congenital scoliosis and dextrocardia. All the patients had overnight pulse oximetry, which showed episodes of desaturation at night. This was reversed with the onset of nocturnal ventilation. All the patients underwent posterior fusion performed by the same surgeon. Mean follow-up was 40 months (range 10 to 75)

Outcome Measures: Lung function, Cobb angle, Length of ICU stay, complications

Results: Mean vital capacity at time of surgery was 20% (range 13–28%). All patients recovered well following surgery with no cardiac or pulmonary complications. The mean stay in the ICU was 2.7 days (range 2–5). The mean hospital stay was 14.2 days (range 10–21). The mean preoperative Cobb angle was 70.2 degrees (range 55–85). The average change in the Cobb angle post-operatively was 32 degrees (range 16–65 degrees). The mean vital capacity of patients at latest follow up was 18% (range 10–32%). There was no loss of correction at latest follow-up. None of these patients lost their ambulatory capacity following surgery.

Conclusion: This is the first study reporting results of deformity correction in patients on ventilatory support. Spinal deformity correction in patients on non-invasive nocturnal ventilation presented no increased risk of complications.

Study Design: A prospective observational study of 12 Adolescent Idiopathic Scoliosis patients undergoing corrective surgery.

Objective: To assess the recovery of respiratory function (specifically diaphragmatic function) after thoracotomy or thoraco-abdominal surgery for Adolescent Idiopathic Scoliosis (AIS) using spirometry and Sniff Nasal Inspiratory Pressure (SNIP).

Summary of Background Data: SNIP is one of the best measures of global inspiratory muscle strength and specifically of diaphragmatic muscle strength. FVC and FEV1 are a better measure of restrictive and obstructive lung function than muscle strength. To the best of our knowledge no study has specifically looked at the recovery of diaphragmatic function following scoliosis surgery.

Subjects: 6 patients (2M, 4F) with thoracic scoliosis underwent a thoracotomy followed by a second stage posterior instrumentation 5–7 days later. The other 6 patients (1M, 5F) with thoraco-lumbar curves had a single stage correction and instrumentation using thoraco-abdominal approach. All patients were operated by the same surgeon.

Outcome Measures: All patients underwent conventional lung function tests (spirometry) and SNIPs during their pre-operative assessment. Spirometry and SNIPs were repeated postoperatively before discharge, at 6 weeks, 3 months and 6 months follow up. The values were compared between the thoracic and thoraco-abdominal groups.

Results: Overall mean preoperative SNIP was 56.75 cm H₂O and overall FVC was 2.79L. The mean SNIP in the thoracotomy group was 57.8 and 55.67 in the thoraco-abdominal group. The mean FVC in the thoracotomy group was 2.9 and in thoraco-abdominal group was 2.66. The difference between the 2 groups was not statistically significant. SNIP values returned to normal within 3 months in the thoraco-abdominal as well as in the thoracotomy groups. The FVC returned to within 95% of pre-operative values in 6 months in the two groups.

Conclusion: This study shows that SNIP return to pre-operative values within 3 months of scoliosis surgery after both thoracotomy and thoraco-abdominal approaches. The thoraco-abdominal approach appears not to have a more detrimental effect on global inspiratory muscle function and diaphragmatic function when compared to thoracotomy.

Objective: To describe Sniff Nasal Inspiratory Pressure (SNIP) a new way of assessing the global respiratory function in scoliosis patients and explain it’s particular relevance in neuromuscular scoliosis. To correlate of SNIP with conventional lung function tests in scoliosis patients. To compare SNIP values between patients with neuromuscular and idiopathic scoliosis.

Design: A prospective observational study of 36 scoliosis patients. All patients underwent conventional lung function tests and SNIP during their pre-operative assessment. The SNIP values were correlated with FVC and FEV1 values obtained by spirometry. The SNIP values of those with neuromuscular scoliosis were compared to those with idiopathic scoliosis and also with the normative data of general population.

Subjects: Thirty-six patients (13M, 23F) with scoliosis. Of them, 17 (1M, 16F) had idiopathic scoliosis and 19 (12M, 7F) had neuromuscular scoliosis. The mean age was 16.5 years (7–54).

Outcome Measures: Comparison of the mean SNIP, FEV1, FVC and FEV1/FVC between the idiopathic and neuromuscular group. Assessing the degree of correlation between SNIP and spirometry data for all patients.

Results: Overall mean SNIP was 50.22 cm H₂O. Average SNIP in the neuromuscular group was 40.92±11.68 and 58.72±21.96 in the idiopathic group (p=0.0127). While the mean FEV1 (p=0.183), FVC (p=0.191) and FEV1/FVC (p=0.721) values were not significantly different between the two groups. The correlation coefficient for spirometry values and SNIP was −0.577 (mean x=−48.86, mean y=1.87) (p=0.0002), indicating very good correlation.

Conclusion: SNIP is the best measure of global inspiratory muscle strength and less subjective than spirometry. It is easier to administer to children. SNIP is better able to distinguish between idiopathic and neuromuscular scoliosis patients, than spirometry and shows good correlation with spirometry values. It can be a useful test in assessment and follow-up of breathing in neuromuscular scoliosis patients.

Late wound infection is a recognised complication of instrumented spinal deformity surgery. In most cases it is a benign complication which usually resolves after implant removal. However, some of our patients with late infection developed a pseudoarthrosis.

To investigate this further we undertook a retrospective review of all patients undergoing implant removal for deep infection between 1991 and 2000.

Twenty-one patients were identified, representing a late infection rate of at least 6%. They showed no specific pre- or intra-operative risk factors. Nine had some problems with early post-operative wound healing, which settled with minimal treatment. Late infection presented as localised swelling or a discharging sinus between 4 and 84 months (average 31 months) post-surgery. Blood parameters were abnormal in 15 cases, frank infection demonstrated in 19 cases, loosening of the implant in four cases and positive bacteriology culture in 14 cases. Wounds healed within 2 to 17 weeks (average 5 weeks) following implant removal, wound debridement and antibiotic therapy lasting 2 to 20 weeks (average 6 weeks). This was delayed until one year post-surgery in the three cases presenting early. Follow-up of between 6 and 92 months (average 38 months) revealed no persistent infection. Pseudoarthrosis developed in seven patients (33%). Four of these patients had progressive deformity warranting refusion and three produced minimal symptoms. Patients developing a pseudoarthrosis had an excess of post-operative wound problems, presented much earlier and had more severe infections compared to those without sequelae.

Late infection is confirmed as a relatively common complication of scoliosis surgery. Implant removal, aggressive debridement and primary closure is confirmed as effective treatment to eradicate the infection. A high rate of pseudoarthrosis is the only sequelae. The excess of early infections in these cases may indicate interference with a critical stage of the fusion process. Preservation of the implants until one year post surgery was unsuccessful at preventing a pseudoarthrosis.