Aims

Our aim was to perform a systematic review of the literature to assess the incidence of post-operative epidural haematomas and wound infections after one-, or two-level, non-complex, lumbar surgery for degenerative disease in patients with, or without post-operative wound drainage.

Background:. Following lumbar spine surgery patients with a high BMI appear to have increased post-operative complications including surgical site infections (SSI), urinary complications, increased anaesthetic/operative time and a greater need for post-operative blood transfusion. There is no current evidence, however, analysing the effect of BMI on functional outcome. Purpose:. We aimed to analyse the effect of BMI on functional outcome following lumbar spine surgery. Study Design:. Retrospective Cohort Study. Patient Sample:. 131. Outcome Measures:. Outcome measures included mean post-operative Oswestry Disability Index (ODI) at six and twelve months, the incidence of SSI, mean operative time and the requirement for post-operative blood transfusion. Methods:. Patients that underwent lumbar spinal surgery between September 2010 and November 2013 were identified retrospectively and categorised into discectomy, decompression, fusion and revision is created. A BMI threshold of 30 was used to group patients as non-obese or obese. Univariate analysis was used to compare the effect of BMI on the above outcome measures. Results:. Post-operative complication rates were higher in the obese group in each category. However, there was no significant difference in the post-operative ODI at six ad twelve months post-operatively. Conclusions:. Increased BMI is related to increased post-operative complications but is not associated with a poorer functional outcome in the short to mid-term

The aim of this study was to review the data held with the NHSLA database over the last 10 years for negligence in spine surgery with particular focus on why patients ‘claim’ and what is the likely outcome. Anonymous retrospective review. We contacted the NHSLA and asked them to provide all data held on their database under the search terms ‘spine surgery or spine surgeon.’. An excel sheet was provided, and this was then studied for reason of ‘claim’, whether the claim was open/closed and outcome. A total of 67 claims of negligence were made against spinal surgeries during this time (2000-09). The number of claims had increased over the last few years: 2000-03, n= 8, 2004-06, n= 46. The lumbar spine remains the most common area (Lumbar: 55/67, Thoracic : 6/67, Cervical 6/67). Documented reasons for claims were post-operative complications (n= 28; 42%), delayed/failure to diagnose (n=24; 36%), discontent with preoperative assessment including consent (n=2; 3%), intra-operative complications (n= 10; 15%) and anaesthesia complication (n=3; 4%). Twenty were closed and 47 remained open. The number of successful claims was 8/20 (40%). The mean compensation paid out was £33,409 (range was £820.5 to £60,693). The number of claims brought against spinal surgeries is on the increase, with the most common area being the lumbar spine which perhaps is not surprising as this is the most common area of spinal surgery. Common reasons are post-operative complications and delay/failure to diagnose. The ‘success’ of these claims over the last 10 years was 8/20 (40%) with mean compensation paid out was £33,409. Ethics approval: None;. Interest Statement: The lead author is the CEO and founder of a Personal Injury/Medico-Legal company

Object. Giant thoracic discs (occupying more than 40% of the spinal canal) are a difficult surgical pathology. They are increasingly being recognized as or particular subset of thoracic disc pathology. It has been recommended that an aggressive surgical approach of open 2 level verteberectomy and instruments should be utilized.21 However Retropleural thoracotomy provides the shortest direct route to the anterior thoracic spine and avoids pleural cavity entry making it an ideal if infrequently used approach to access ventral thoracic and thoracolumbar spine abnormalities. We present a detailed description of our experience utilising this approach, for the treatment of Giant Thoracic discs without the need for vertebrectomy or instrumentation. Methods. A prospective cohort of patients with Giant thoracic discs operated on utilizing the mini open retropleural thoracotomy technique was used, intra-operative and post-operative complications and length of post-op stay. Functional outcome and pain scores, were also prospectively recorded using SF-36, Oswestry Disability Index (ODI), and visual analogue pain scores (VAS). Results. 17 patients underwent a retropleural thoracotomy for Giant thoracic disc between 2001 and 2010. There were 8 male and 9 female patients with a median age of 50 years (range 35 – 70). The surgical level was T8/9 (58%) followed by T10/11 (33%) and finally T11/12 (8%). 1 patient had redo surgery following a failed primary discectomy at another institution. The mean post-operative length of stay was 12.8 days Intra-operative complications included 5 pleural tears during the approach. Chest drain was placed post-op in one patient. The tears were primarily repaired and the approach did not have to be abandoned. 2 patients had an intra-operative CSF leak (1 had intradural disc erosion). Post-operative complications included 1 pleural effusion, 1 patient had pneumonia and a PE, 1 patient died from an unrelated respiratory tract infection of the lung (opposite to the side of the approach) 40 days after surgery. Conclusion. Large calcified thoracic disc herniations can be a very challenging pathology. The retropleural transthoracic approach can be employed safely in this setting with acceptable morbidity for the patient

Aims. To address the natural history of severe post-tuberculous (TB) kyphosis, with focus upon the long-term neurological outcome, occurrence of restrictive lung disease, and the effect on life expectancy. . Patients and Methods. This is a retrospective clinical review of prospectively collected imaging data based at a single institute. A total of 24 patients of Southern Chinese origin who presented with spinal TB with a mean of 113° of kyphosis (65° to 159°) who fulfilled inclusion criteria were reviewed. Plain radiographs were used to assess the degree of spinal deformity. Myelography, CT and MRI were used when available to assess the integrity of the spinal cord and canal. Patient demographics, age of onset of spinal TB and interventions, types of surgical procedure, intra- and post-operative complications, and neurological status were assessed. . Results. All except one of the 24 patients were treated with anti-TB chemotherapy when they were first diagnosed with spinal TB. They subsequently received surgery either for neurological deterioration, or deformity correction in later life. The mean follow-up was 34 years (11 to 59) since these surgical interventions. Some 16 patients (66.7%) suffered from late neurological deterioration at a mean of 26 years (8 to 49) after the initial drug treatment. The causes of neurological deterioration were healed disease in nine patients (56.2%), re-activation in six patients (37.5%) and adjacent level spinal stenosis in one patient (6.3%). The result of surgery was worse in healed disease. Eight patients without neurological deterioration received surgery to correct the kyphosis. The mean correction ranged from 97° to 72°. Three patients who were clinically quiescent with no neurological deterioration were found to have active TB of the spine. Solid fusion was achieved in all cases and no patient suffered from neurological deterioration after 42 years of follow-up. On final follow-up, six patients were noted to have deceased (age range: 47 years to 75 years). Conclusion. Our study presents one of the longest assessments of spinal TB with severe kyphosis. Severe post-TB kyphosis may lead to significant health problems many years following the initial drug treatment. Early surgical correction of the kyphosis, solid fusion and regular surveillance may avoid late complications. Paraplegia, restrictive lung disease and early onset kyphosis might relate to early death. Clinically quiescent disease does not mean cure. . Cite this article: Bone Joint J 2017;99-B:1381–8

Background:. Lumbar intraspinal cysts (LICs) are rare incidental MRI findings in back pain. Their space-occupying nature make them plausible factors in both non-specific and radicular back pain. Methods:. Retrospective cohort study of patients with MRI reports of LICs at our center over 5 years. N=26, 13 male, mean age 66 ± 12 years. Results:. LICs originated at levels from L1-S2 (61.5% at L4/5), reaching 17mm. 2. (rapid one year progression in this case). LICs were described as synovial in all but two cases (hemorrhagic cyst; Tarlov perineural cysts). Background degenerative changes were reported in 88.5% of cases. Patients described up to 30-year histories of non-specific back pain. Clinical features of radiculopathy plus concomitant MRI findings were indications for surgical decompression (n=14) and cyst excision (n=13/14). 2 cases of spontaneous LIC resolution, and 2 cases of post-operative complications were identified (inflammatory/scar tissue stenosis). 0% cyst recurrence rate with sustained resolution of symptoms currently stands. Conclusions:. Frequent co-existence of LICs with degeneration implicates the former as a product of osteoarthritic processes, conceivably contributing to patient accounts of chronic non-specific pain. LICs may equally constitute acute direct causes of radiculopathy, owing to their diverse origins and potential to rapidly expand. A role of LICs in axial and radicular pain, independent of other degenerative changes, is supported by symptom alleviation in cases of spontaneous resolution, versus progression with decompression performed without cyst excision (Tarlov cyst), or following novel cyst formation at the level of previous spinal fusion. Whether image-guided aspiration might reduce surgery-related side-effects is a topic for further work

There are few reports of the treatment of lumbar tuberculous spondylitis using the posterior approach. Between January 1999 and February 2004, 16 patients underwent posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation. Their mean age at surgery was 51 years (28 to 66). The mean follow-up period was 33 months (24 to 48). The clinical outcome was assessed using the Frankel neurological classification and the Kirkaldy-Willis criteria. On the Frankel classification, one patient improved by two grades (C to E), seven by one grade, and eight showed no change. The Kirkaldy-Willis functional outcome was classified as excellent in eight patients, good in five, fair in two and poor in one. Bony union was achieved within one year in 15 patients. The mean pre-operative lordotic angle was 27.8° (9° to 45°) which improved by the final follow-up to 35.8° (28° to 48°). Post-operative complications occurred in four patients, transient root injury in two, a superficial wound infection in one and a deep wound infection in one, in whom the implant was removed. Our results show that a posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation for tuberculous spondylitis through the posterior approach can give satisfactory results

Aims. Clinical and radiological data were reviewed for all patients with mucopolysaccharidoses (MPS) with thoracolumbar kyphosis managed non-operatively or operatively in our institution. Methods. In all 16 patients were included (eight female: eight male; 50% male), of whom nine had Hurler, five Morquio and two Hunter syndrome. Six patients were treated non-operatively (mean age at presentation of 6.3 years; 0.4 to 12.9); mean kyphotic progression +1.5. o. /year; mean follow-up of 3.1 years (1 to 5.1) and ten patients operatively (mean age at presentation of 4.7 years; 0.9 to 14.4); mean kyphotic progression 10.8. o. /year; mean follow-up of 8.2 years; 4.8 to 11.8) by circumferential arthrodesis with posterior instrumentation in patients with flexible deformities (n = 6). Results. In the surgical group (mean age at surgery of 6.6 years; 2.4 to 16.8); mean post-operative follow-up of 6.3 years (3.5 to 10.3), mean pre-operative thoracolumbar kyphosis of 74.3. o. (42. o. to 110. o. ) was corrected to mean of 28.6. o. (0. o. to 65. o. ) post-operatively, relating to a mean deformity correction of 66.9% (31% to 100%). Surgical complications included a deep wound infection treated by early debridement, apical non-union treated by posterior re-grafting, and stable adjacent segment spondylolisthesis managed non-operatively. Thoracolumbar kyphosis > +38. o. at initial presentation was identified as predicting progressively severe deformity with 90% sensitivity and 83% specificity. Discussion. This study demonstrates that severe thoracolumbar kyphosis in patients with MPS can be effectively treated by circumferential arthrodesis. Severity of kyphosis at initial presentation may predict progression of thoracolumbar deformity. Patients with MPS may be particularly susceptible to post-operative complications due to the underlying connective tissue disorder and inherent immunological compromise. Take home message: Clinical and radiological data were reviewed for all patients with mucopolysaccharidoses with thoracolumbar kyphosis managed non-operatively or operatively in our institution. Cite this article: Bone Joint J 2016;98-B:229–37

We investigated the incidence of anomalies in the vertebral arteries and Circle of Willis with three-dimensional CT angiography in 55 consecutive patients who had undergone an instrumented posterior fusion of the cervical spine. We recorded any peri-operative and post-operative complications. The frequency of congenital anomalies was 30.9%, abnormal vertebral artery blood flow was 58.2% and vertebral artery dominance 40%. . The posterior communicating artery was occluded on one side in 41.8% of patients and bilaterally in 38.2%. Variations in the vertebral arteries and Circle of Willis were not significantly related to the presence or absence of posterior communicating arteries. Importantly, 18.2% of patients showed characteristic variations in the Circle of Willis with unilateral vertebral artery stenosis or a dominant vertebral artery, indicating that injury may cause lethal complications. One patient had post-operative cerebellar symptoms due to intra-operative injury of the vertebral artery, and one underwent a different surgical procedure because of insufficient collateral circulation. . Pre-operative assessment of the vertebral arteries and Circle of Willis is essential if a posterior spinal fusion with instrumentation is to be carried out safely. Cite this article: Bone Joint J 2014;96-B:535–40

Aim:. Our aim was to report the rate and risk factors for post-operative complications in Duchenne Muscular Dystrophy (DMD) patients undergoing spinal arthrodesis for scoliosis, with a comparison to neuromuscular scoliosis of other aetiology. Methods:. From a prospective single surgeon spinal deformity database, we identified all patients with neuromuscular disorders who underwent surgical correction for progressive scoliosis. We recorded demographic and peri-operative data, including complications and subsequent procedures. The rate and risk factors for complications was determined, with a sub-analysis of the DMD group to determine any peri-operative factors predictive of overall complication rates. Results:. There were 98 patients, 59 (60%) were male with mean age at surgery 14 yrs (7–19 yrs). Forty-eight patients had cerebral palsy (n=48, 49%) and 26 DMD (27%). The overall complication rate was 18.4% (n=18), with deep wound infection (DWI; n=9, 9.2%) and acute liver injury (ALI; n=4, 4.0%) most frequent. The complication rate was significantly higher in DMD patients (35%) compared to other neuromuscular disorders (13%; p=0.013). All ALIs occurred in DMD patients (p=0.004), with an increased DWI rate (19% vs 6%; p=0.053). On subanalysis, no peri-operative factors correlated with overall complication rate or DWI rate. Increased intraoperative blood loss was the only factor associated with ALI (p=0.036). Discussion:. Scoliosis correction has an acceptable complication rate in patients with neuromuscular diagnoses. DMD patients have an increased complication rate when compared to other neuromuscular disorders. ALI in our series was unique to DMD patients and we would recommend peri-operative vigilance for hepatotoxicity in these patients. Conflict Of Interest Statement: No conflict of interest

To describe complications and reoperation rates associated with degenerative spinal deformity surgery. A retrospective review of prospectively collected data from a single spinal surgeon in the United Kingdom. A total of 107 patients who underwent surgery, of 5 or more levels, for primary degenerative kyphoscoliosis between 2006 and 2012 were identified. Clinical notes were reviewed and post-operative complications, reoperation rates, length of follow up and mortality were analysed. A total of 107 patients, average aged 66.5 years (range 52 – 85), with 80% women. 105 patients underwent posterior surgery, two patients required both anterior and posterior surgery. The average number of instrumented levels was 8.3; 10% 5 levels, 15% 6 levels, 11% 7 levels, 14% 8 levels, 15% 9 levels and 35% had fusions of 10 levels and above. 58% included fixation to sacrum or pelvis. 93% had a decompression performed and 30% had an osteotomy. There were 40 complications recorded within the follow-up period. Infection occurred in 7 patients (6.5%). All were successfully managed with debridement, antibiotic therapy and retention of implants. There were 4 dural tears (3.7%). One patient developed a post-operative DVT (0.9%). No patients sustained cord level deficits. Prevalence of mechanical complications requiring re-operation was 26% (28 patients). 5 patients (4.7) required revision surgery for symptomatic pseudarthrosis, 7 patients (6.5%) underwent revision fixation for metal work failure (broken rods/screw pull-out) and 16 patients (14.9%) underwent revision surgery to extend fixation proximally or distally due to adjacent segment disease (symptomatic proximal junction kyphosis 4.7%; osteoporotic fracture 3.7% and junctional/nerve root pain 6.5%). Overall reoperation rate was 32.5% at an average of 1.9 years following primary surgery (range 1 week–6 years). 37% patients remain on regular outpatient review (average 3.8 years following first surgery; range 2–6 years). 52% have been discharged after a mean follow-up of 2.3 years. 11 patients had died since their surgery (10.2%) at an average 4.1 years following their spinal surgery (range 1 –5.9 years). Overall complication rate was 37.3%. 32.5% of patients were re-operated for infective or mechanical complications. 52% of patients had been discharged at an average of 2.3 years following their surgery. 10.2% of patients had died within 6 years of surgery

We reviewed 31 consecutive patients with Friedreich’s ataxia and scoliosis. There were 24 males and seven females with a mean age at presentation of 15.5 years (8.6 to 30.8) and a mean curve of 51° (13° to 140°). A total of 12 patients had thoracic curvatures, 11 had thoracolumbar and eight had double thoracic/lumbar. Two patients had long thoracolumbar collapsing scoliosis with pelvic obliquity and four had hyperkyphosis. Left-sided thoracic curves in nine patients (45%) and increased thoracic kyphosis differentiated these deformities from adolescent idiopathic scoliosis. There were 17 patients who underwent a posterior instrumented spinal fusion at mean age of 13.35 years, which achieved and maintained good correction of the deformity. Post-operative complications included one death due to cardiorespiratory failure, one revision to address nonunion and four patients with proximal junctional kyphosis who did not need extension of the fusion. There were no neurological complications and no wound infections. The rate of progression of the scoliosis in children kept under simple observation and those treated with bracing was less for lumbar curves during bracing and similar for thoracic curves. The scoliosis progressed in seven of nine children initially treated with a brace who later required surgery. Two patients presented after skeletal maturity with balanced curves not requiring correction. Three patients with severe deformities who would benefit from corrective surgery had significant cardiac co-morbidities

Between 1993 and 2008, 41 patients underwent total coccygectomy for coccydynia which had failed to respond to six months of conservative management. Of these, 40 patients were available for clinical review and 39 completed a questionnaire giving their evaluation of the effect of the operation. Excellent or good results were obtained in 33 of the 41 patients, comprising 18 of the 21 patients with coccydynia due to trauma, five of the eight patients with symptoms following childbirth and ten of 12 idiopathic onset. In eight patients the results were moderate or poor, although none described worse pain after the operation. The only post-operative complication was superficial wound infection which occurred in five patients and which settled fully with antibiotic treatment. One patient required re-operation for excision of the distal cornua of the sacrum. Total coccygectomy offered satisfactory relief of pain in the majority of patients regardless of the cause of their symptoms

The aim of this study was to prospectively assess the outcome of patients with metastatic spinal disease who underwent minimally invasive fixation of the spine for intractable pain or spinal instability. This is a prospective audit of patients with metastatic spinal cord disease who have undergone minimally invasive fixation of the spine from August 2009 until the present date. This was assessed by pre and post-operative Oswestry Disability Index (ODI), EQ5D and Tokuhashi scores. Intra- and post-operative complications, time to theatre, length of inpatient stay, analgesia requirements, mobility, chest drain requirement and post-operative HDU and ITU stays were also recorded. So far, 10 patients have met the criteria. There were no intra-operative complications. Post-operatively, there were no complications, chest drains, increase in analgesia or stay on the HDU or ITU. All patients showed an improvement in mobility. The mean post-operative day of mobilisation was 2 days, post-operative days until discharge 5.3 days and length of inpatient stay was shorter than traditional surgery. Blood loss was minimum except one patient with metastatic renal cell carcinoma who needed transfusion intraoperatively. ODI, VAS and EQ-5D scores were calculated and were significantly improved compared to preoperatively. This novel approach to management of metastatic spinal disease has resulted in improved mobility, short inpatient stays without the need for chest drains, HDU or ITU and an improved the quality of life in pallliative patients. This is a completely new strategy to treat the pain in these patients without the usual associated risks of surgery and has major advantages over traditional surgical techniques which may preclude this group of patients having any surgical stabilisation procedure at all

Anterior only procedure for stable thoraco-lumbar burst fractures is controversial. Prospective collection of clinical and radiological data in stable burst fractures with neurological deficit undergoing anterior only decompression and stabilisation with 2-year follow-up. 14 consecutive patients (8 females, 6 males) with two-column thoracolumbar burst fracture and neurological deficit underwent anterior corpectomy/hemi-corpectomy and instrumentation, from February 2007 to February 2009. Radiological data included classification of fracture (AO classification), kyphus angle and degree of canal compromise. Post-operative CT scans done to assess radiological improvement. Clinical data included neurological deficit at presentation, improvement or changes in neurology, length of surgery, estimated blood loss, post-operative complications and length of stay. Commonest mechanism was fall from height. 10 patients had incomplete burst fractures amenable to hemi-corpectomy. 8 of our patients were ASIA D, 4 were ASIA C or lower. They all improved by at least one grade. 2 patients had identical ASIA grade pre and post operatively. Pre-operative spinal canal compromise averaged 52.6% and vertebral body height loss averaged 48.9%. The mean kyphotic angles improved from 19.6° to 7.9 °. There were two cases with minor injury to the diaphragm, one developing a pneumothorax. Mean length of surgery and hospital stay were 4hours and 21minutes and 11.8 days respectively. The fractures in which the top part is burst and causing canal compromise, could be dealt with by top hemi-corpectomy requiring smaller approach. One stage anterior – only stabilization can yield successful clinical results

Background. Surgical patients have cost the NHS 1.3 billion GBP from 1995. Spinal pathologies can present diagnostic challenges, and the consequences of delayed diagnosis or surgical complications can be devastating and so creating high indemnity costs. We aim to highlight the spinal associated litigation patterns within the United Kingdom. Method. Data was obtained from the NHS Litigation Authority from 2002 to 2010. Result. From 236 claims, 144 were related to trauma or acute diagnostic issues and 92 from elective surgery. The financial burden to the NHS came to 60.5 million GBP. Of this sum 42.8 million GBP were paid in damages, and the remaining 29% in legal costs. The financial costs were similar for trauma and elective cases. The most frequent cause of successful litigation for trauma were, missed fractures(41.7%), missed cauda equina(23.6%) and spinal infection(11.8%). The emergency department(43.8%), orthopaedic surgery(28.5%) and Medicine(13.9%) bore the brunt of the claims. For elective surgery, Spinal Damage(19.8%), failure in Post-Operative Care(15.4%), Infection(11%) and Wrong Level Surgery, Cauda Equina and Surgical Failure(9.9% each). were likely to result in a successful claim, and the litigation burden was felt by the orthopaedic(60.4%), Neurosurgery(18.7%) and other surgical disciplines(11%). Conclusion. Acute spinal fractures, cord compression and infection should be considered in patients in the emergency department setting, with appropriate examination and investigations for uncertainty. A lack of awareness of at risk cases increases the likelihood of a pay-out and sums involved. For elective spinal surgery, a failure in the consenting process and the technical skill of the surgeon are likely to result in a pay-out. A failure to identify post-operative complications such as infection and thromboembolism are also indefensible. Protecting patients intra-operatively and maintaining high technical expertise and vigilance post-operatively in an adequately consented patient may decrease litigation rates

The “Wallis” implant is indicated to stabilize symptomatic degenerative lumbar spine segments, relieving low back pain related to instability and thus delaying the need for irreversible, more invasive surgical management. The purpose of this study was to provide the first objective clinical evaluation of the “Wallis” lumbar dynamic stabilisation system. An independent prospective observational study was carried out utlising SF-36, Oswestry Disability Index (ODI) and visual analogue pain scores (VAS). Surgical pathologies in which this technique was used, the intra-operative and post-operative complications and length of post-op stay were recorded. 102 patients underwent Wallis insertion between June 2007- May 2009, Median age 51.5 (range 28-108). 94% of patients completed questionnaires and were followed up at 3, 6 and 12 month time points. ODI scores decreased from pre-op 39 to 27 at twelve months (p<.0016). VAS back pain scores decreased 59 to 36 (p<0.0001). Leg scores decreased 50 to 39 (p<0.0002). SF 36 scores improved significantly, physical functioning 46 to 59, physical health 30 to 54 and social functioning 47 to 68. 50% of patients believed their health to be better 12 months post-op. Pre-operatively 28% of patients were employed and working with 26% off work due to back problems. This rate increased steadily with 42% employed at 12 months. Two implants were removed, one due to non-benefit with subsequent arthrodesis and one due to infection. One superficial wound infection occurred. The Wallis dynamic stabilization system provides a superficial and easily reversible surgical procedure with a lower complication rate than conventional athrodesis. Used in patients with painful degenerative lumbar conditions their quality of life objectively approached values of the age- and gender-matched general population

Aims

We compared the clinical and radiological outcomes of using a polyetheretherketone cage with (TiPEEK) and without a titanium coating (PEEK) for instrumented transforaminal lumbar interbody fusion (TLIF).

Aims

Patients seeking cervical spine surgery are thought to be increasing in age, comorbidities and functional debilitation. The changing demographics of this population may significantly impact the outcomes of their care, specifically with regards to complications. In this study, our goals were to determine the rates of functionally dependent patients undergoing elective cervical spine procedures and to assess the effect of functional dependence on 30-day morbidity and mortality using a large, validated national cohort.

Aims

The aim of this study was a quantitative analysis of a surgeon’s learning curve for scoliosis surgery and the relationship between the surgeon’s experience and post-operative outcomes, which has not been previously well described.