To analyse the causes and factors associated with mortality in patients admitted to ASCI unit in a low- or middle-income country. The study was performed at a Tertiary Hospital at Groote Schuur Hospital, Cape Town South Africa

Data between 1996 –2022 were retrospectively collected from hospital records of patients admitted to the ASCI Unit. There was approximately 3223 admissions for the study period. 682 patients were confirmed dead 87% were male and 64% were unemployed. The mean age was 46 years (ranging from 14 – 87 years).

A 1/3 of injuries were caused by a MVA, a ¼ by a fall (low energy and from a height), and 1/5 by a gunshot wound. Average length of stay was 47 days (SD = 52 days), ranging from as short as 1 day to 512 days for one patient. Majority (65%) were admitted for more than a week but less than 2 months 32% were ventilated, and 17% with a CPAP facemask. 10% of patients had a pre-existing ulcer prior to admission. 65% of patients had surgery via the posterior approach, 33% via the anterior approach. On average patients died within 5 years of being admitted to hospital, ranging from dying in the same year as the injury to 20 years later. 73% of the deaths were classified as natural deaths and 20% as unnatural.

There is a high mortality in patients with acute spinal cord injury, causes are multifactorial, and in depth critical analyses is required to improve clinical outcomes and rationalise resource allocation.

Specific and rapid detection methods for spinal tuberculosis, with sufficient sensitivity in HIV-1 co-infected individuals, are needed, to ensure early initiation of appropriate treatment to prevent physical disability and neurological fallout. In addition, understanding the systemic and local pathophysiology of spinal tuberculosis, and its interaction with HIV-1 infection, is crucial to guide future therapeutic interventions.

We prospectively enrolled adult patients presenting with signs and symptoms of suspected spinal tuberculosis, at Groote Schuur Hospital, between November 2020 and December 2021. TB diagnostic testing was performed on open and CT-guided spinal biopsies using Xpert MTB/RIF Ultra compared to gold standards TB culture and histology. A highly sensitive droplet digital PCR assay for detecting and quantifying Mycobacterium tuberculosis complex (MTBC) and HIV-1 DNA was tested. Plasma inflammatory proteins were measured to assess systemic inflammation.

Xpert Ultra had a high sensitivity of 94.7% and specificity of 100% for STB against TB culture and histology in both open and CT-guided biopsy samples. The ddPCR assay confirmed TB detection in 94% of patients with positive Xpert Ultra results. Four patients with negative TB diagnostic results had MTBC DNA detected by ddPCR. HIV-1 DNA was detected in the spinal tissues from all HIV-1-infected patients. MTBC DNA levels were significantly higher in HIV-1-co-infected spinal tissue samples (p< 0.01). We identified four biomarkers significantly associated with higher bacterial burden at the disease site (p< 0.01).

Xpert Ultra and MTBC ddPCR improve the detection of STB. DdPCR can be utilized as an additional, highly sensitive tool for detecting and quantifying Mtb, in pathological samples that may be paucibacillary. These findings provide novel diagnostic and pathophysiologic insight into STB, in the context of HIV-1 infection, and provide rationale to include these tests in hospital and research settings for patients from communities burdened by TB and HIV-1.

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine characterized by a Cobb angle of at least 10 degrees. The goal of surgery is to not only prevent progression but restore sagittal and coronal balance, protecting cardiopulmonary function and improving cosmesis.

We reviewed the impact of deformity correction surgery in terms of radiology and patient reported outcome(PROMs).

The senior authors prospectively maintained database from 2003 –2022 was retrospectively analysed in terms of pre- and post-operative patient reported outcome measures (SRS 22) as well as radiological parameters.

44 patients with AIS were identified with pre and post op PROMS. The average age at surgery was 15yrs with 84% female. 38% had a Lenke 1 curve and 3 patients had Lenke 6 curves. 73% had posterior surgery.

There was a total improvement in SRS 22 scores by 7.8%. Patients reported significant satisfaction with treatment 4.8/5 and improvement in self-image with a change of 0.4 (p<0.001). However, no difference in function, pain and mental health were recorded.

Overall, proximal thoracic (PT) curves improved from 24 degrees to 11 degrees (p<0.001), Main thoracic (MT) curve 55 degrees to 19 degrees and Thoracolumbar/Lumbar curves (TL/L) 45 degreesto 11 degrees. Pre-operative flexibility and post-operative correction were 0.40 and 0.41 respectively for PT curve. MT was 0.32 and 0.67. That for TL/L was 0.57 and 0.71 respectively.

Surgery yields significant main curve correction correlating with high patient reported satisfaction rate. Although total SRS 22 score yielded 7.8% improvement, sub-analysis of self-image showed the most significant improvement.

Adolescent idiopathic scoliosis is a three-dimensional deformity of the spine, affecting 1–3% of the population.

Most cases are treated conservatively. Curves exceeding 45° in the thoracic spine and 40° in the lumbar spine may require correction and fusion surgery, to limit the progression of the curve and prevent restrictive pulmonary insufficiency (curves above 70°). When fusion is required, it may be performed either by posterior or anterior approaches. Posterior is useful for thoracic (Lenke I) curves, notably to correct the thoracic hypokyphosis frequently observed in AIS. Anterior approaches by thoraco-lombotomies allow an effective correction of thoraco-lumbar and lumbar curves (Lenke V and VI), with fewer levels fused than with posterior approaches. However, the approach requires diaphragm splitting and one may be concerned about the long-term pulmonary consequences. The literature provides conflicting insight regarding the consequences of the approach in anterior scoliosis correction, the interpretation of the results being difficult knowing that the correction of the scoliosis itself may improve pulmonary function.

This is a retrospective observational study done at a Tertiary Institution. The HRQOL scores have been collected as a prospective cohort. Clinical and radiographic data was collected from patients charts and analysed by two senior surgeons

A cohort of 64 patients were operated in the given time period. 50 patients met the inclusion criteria. No major complications were reported. The Union rate was 100% and no post operative complications were noted. Pre and post SRS scores improved in all patients.

The Anterior approach for Lenke V AIS gives great surgical exposure and allows for excellent correction of Cobb angle with minimal risk to the patient.

Aims

Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy.

Background:

Severe kyphosis in myelomeningocoele patients results in seating problems, early satiety and ultimately pressure sores over the prominence. Kyphectomy and sagittal correction can improve these morbidities.

Background:

GeneXpert, a new, rapid molecular diagnostic test is recommended as the first line investigation for suspected pulmonary TB in areas of high HIV prevalence or drug resistance, yet it has not been validated for the diagnosis of musculoskeletal TB.

Background:

Cervical spine injured patients often require prolonged ventilatory support due to intercostal paralysis and recurrent chest infections. This may necessitate tracheotomy. Concern exists around increased complications when anterior cervical spine surgery and tracheotomies are performed.

Background:

Spinal deformity surgery carries the risk of loss of neurological function which may be permanent. Although the overall the incidence is low it is much higher in complex congenital deformities or those with pre-existing myelopathy. Intra-operative spinal cord monitoring allows this risk to be reduced by providing feedback to the surgeon while the corrective manoeuvres are performed.

Although ideally a trained technician with multimodal monitoring is recommended, it is often not an option in a resource limited environment and surgeon operated technology is used.

Purpose

To review the outcome of multilevel (≥4) instrumented lumbar fusion to sacrum / pelvis performed for degenerative conditions

Introduction:

Trauma is endemic in South Africa. The upper thoracic spine is extremely difficult to image and assess clearly with frontline x-rays resulting in up to 22% of proximal fractures being missed.

Introduction:

Circumferential arthrodesis of the spine may be achieved by posterior-only or anterior and posterior surgery. Posterior-based interbody fusions have significant limitations including unreliable improvement of segmental lordosis and variable rates of post-operative radiculopathy. Combined anterior and posterior surgery introduces significant cost and peri-operative morbidity. The purpose of this paper is to report the radiographic and clinical outcomes of posterior-based circumferential arthrodesis using a novel expandable interbody cage.

Aim:

Historically, anterior decompression followed by posterior fusion has been the surgical management of choice in spinal tuberculosis. Due to theatre time being at a premium, we have evolved to performing anterior only debridement, allograft strut reconstruction and instrumentation for tuberculosis in the adult thoracic spine.

The aim of this study is to review the safety and the efficacy of this treatment.

Purpose of study

The aim is to assess the use of non-fusion instrumentation “growth rods” in early onset scoliosis (EOS).

Purpose

To determine whether MRI done prior to reduction altered the surgeon's choice of reduction method.

Objectives

To demonstrate that instrumented fusion of the paediatric cervical spine is possible and can be performed safely.

Objective

Posterior vertebral column resection (PVCR) is indicated in the management of severe rigid spine deformities. It is a complex surgical procedure and is only performed in a few spine centres due to the technical expertise required and associated risk. The purpose of this study is to review the indications, surgical challenges and outcomes of patients undergoing PVCR.

Purpose of study

Transarticular screw fixation offers acceptably high fusion rates but is not possible in 18% of patients due to a high riding vertebral artery. It also requires pre-operative anatomical reduction which is not always possible. The Harms' technique utilises a posterior C1 lateral mass and C2 pedicle screw. This allows easier access due to the angle of drilling and has become an increasingly popular surgical technique.

The aim of this study is to review and compare the above techniques with regard to surgery, complications and outcome.

Aim

To investigate anterior instrumented corrective fusion for thoracolumbar or lumbar scoliosis.

Purpose of the study

The aim of the study was to review the surgical management of Neuromuscular Scoliosis (NMS) and its outcome.

Purpose

To perform an Interrater reliability study determining the agreement between an Orthopaedic team and a Radiology team on the MRI features of prolapsed uncontained cervical discs in Flexion-Distraction injuries of the cervical spine. This leads us to determine how many patients demonstrated evidence of a ‘dangerous’ disc: an uncontained disc herniating posteriorly that may be drawn into the spinal canal during closed reduction.

Purpose of study

The vast majority of C2 ring fractures can be managed non-operatively but occasionally the situation precludes this and surgery is considered. Thus study reviews our indications and surgical options in this scenario.

Peripheral nerve injuries (PNI) occur in 10% of combat casualties. In the immediate field-hospital setting, an insensate limb can affect the surgeon's assessment of limb viability and in the long-term PNI remain a source of considerable morbidity. Therefore the aims of this study are to document the recovery of combat PNI, as well as report on the effect of current medical management in improving functional outcome. In this study, we present the largest series of combat related PNI in Coalition troops since World War II.

From May 2007 – May 2010, 100 consecutive patients (261 nerve injuries) were prospectively reviewed in a specialist PNI clinic. The functional recovery of each PNI was determined using the MRC grading classification (good, fair and poor). In addition, the incidence of neuropathic pain, the results of nerve grafting procedures, the return of plantar sensation, and the patients' current military occupational grading was recorded.

At mean follow up 26.7 months, 175(65%) of nerve injuries had a good recovery, 57(21%) had a fair recovery and 39(14%) had a poor functional recovery. Neuropathic pain was noted in 33 patients, with Causalgia present in 5 cases. In 27(83%) patients, pain was resolved by medication, neurolysis or nerve grafting. In 35 cases, nerve repair was attempted at median 6 days from injury. Of these 62%(22) gained a good or fair recovery with 37%(13) having a poor functional result. Forty-two patients (47 limbs) initially presented with an insensate foot. At final follow up (mean 25.4 months), 89%(42 limbs) had a return of protective plantar sensation. Overall, 9 patients were able to return to full military duty (P2), with 45 deemed unfit for military service (P0 or P8).

This study demonstrates that the majority of combat PNI will show some functional recovery. Adherence to the principles of war surgery to ensure that the wound is clear of infection and associated vascular and skeletal injuries are promptly treated will provide the optimal environment for nerve recovery. Although neuropathic pain affects a significant proportion of casualties, pharmacological and surgical intervention can alleviate the majority of symptoms. Finally, the presence of an insensate limb at initial surgery, should not be used as a marker of limb viability. The key to recovery of the PNI patient lies in a multi-disciplinary approach. Essential to this is regular surgical review to assess progress and to initiate prompt surgical intervention when needed. This approach allows early determination of prognosis, which is of huge value to the rehabilitating patient psychologically, and to the whole rehabilitation team.

Introduction

We present a series of patients who have had secondary reconstruction of war injuries to the upper and lower limbs, sustained during the Iraq and Afghanistan conflicts.

The outcomes of 261 nerve injuries in 100 patients were graded good in 173 cases (66%), fair in 70 (26.8%) and poor in 18 (6.9%) at the final review (median 28.4 months (1.3 to 64.2)). The initial grades for the 42 sutures and graft were 11 good, 14 fair and 17 poor. After subsequent revision repairs in seven, neurolyses in 11 and free vascularised fasciocutaneous flaps in 11, the final grades were 15 good, 18 fair and nine poor. Pain was relieved in 30 of 36 patients by nerve repair, revision of repair or neurolysis, and flaps when indicated. The difference in outcome between penetrating missile wounds and those caused by explosions was not statistically significant; in the latter group the onset of recovery from focal conduction block was delayed (mean 4.7 months (2.5 to 10.2) vs 3.8 months (0.6 to 6); p = 0.0001). A total of 42 patients (47 lower limbs) presented with an insensate foot. By final review (mean 27.4 months (20 to 36)) plantar sensation was good in 26 limbs (55%), fair in 16 (34%) and poor in five (11%). Nine patients returned to full military duties, 18 to restricted duties, 30 to sedentary work, and 43 were discharged from military service. Effective rehabilitation must be early, integrated and vigorous. The responsible surgeons must be firmly embedded in the process, at times exerting leadership.

We describe 261 peripheral nerve injuries sustained in war by 100 consecutive service men and women injured in Iraq and Afghanistan. Their mean age was 26.5 years (18.1 to 42.6), the median interval between injury and first review was 4.2 months (mean 8.4 months (0.36 to 48.49)) and median follow-up was 28.4 months (mean 20.5 months (1.3 to 64.2)). The nerve lesions were predominantly focal prolonged conduction block/neurapraxia in 116 (45%), axonotmesis in 92 (35%) and neurotmesis in 53 (20%) and were evenly distributed between the upper and the lower limbs. Explosions accounted for 164 (63%): 213 (82%) nerve injuries were associated with open wounds. Two or more main nerves were injured in 70 patients. The ulnar, common peroneal and tibial nerves were most commonly injured. In 69 patients there was a vascular injury, fracture, or both at the level of the nerve lesion. Major tissue loss was present in 50 patients: amputation of at least one limb was needed in 18. A total of 36 patients continued in severe neuropathic pain.

This paper outlines the methods used in the assessment of these injuries and provides information about the depth and distribution of the nerve lesions, their associated injuries and neuropathic pain syndromes.

Physeal bar resection for partial growth plate arrest was first described by Langenskjold in 1967. The initial enthusiasm by Peterson (1989) who found that 83% of patients resumed physeal growth was tempered by Birch (1992) who only had 33% success. Poor results were due to failure to resume growth or premature growth arrest.

We retrospectively reviewed 21 physeal bar resections performed in 19 children from 1987 to 2003. The average age at surgery was 8.2 years (range 3–12 years). The aetiology of the physeal arrest was : growth plate fracture (8), meningococcal septicaemia (5), osteitis (3; 2 neonatal), dysplasia (3), gunshot (1) and idiopathic (1). The commonest site was the distal femur (12; 5 due to growth plate fracture), followed by the proximal tibia (5; 3 due to meningococcal septicaemia), and the distal tibia (4; 2 due to growth plate fractures). Assessment of the size and location of the bar was with biplanar tomography in 7, MRI in 5 and both in 7. We found equal accuracy with both modalities, but currently prefer MRI. The bar was plotted on an anterior-posterior and lateral map of the growth plate. The average size of the bar was 25% (range 15 to 50%) of the area of the growth plate. Only 3 bars were larger than 30%. Fifteen of the bars were peripheral, 5 linear and 1 central.

Results were classified poor if there was no resumption of growth or if premature growth plate arrest occurred, good if there was resumption of growth which continued to maturity or to follow-up, and excellent if the growth exceeded the expected growth. There were 5 (24%) poor results; all failed to resume growth. Three bars exceeded 30% and 2 were due to meningococcal septicaemia. The remaining 16 bars were followed up for a range of 2 to 12 years; 10 to maturity. Four (19%) had an excellent and 12 (57%) had a good result.

The authors conclude that physeal bar resection is a worthwhile procedure if the size of the bar is equal to or less than 30% of the area of the growth plate. In growth arrest due to meningococcal septicaemia we only had a 60% success rate.

This paper reviews 46 consecutive spinal tuberculosis patients who underwent spinal surgery at a state facility over 2.5 years.

The 21 male and 25 female patients ranged in age from 18 months to 67 years, with 19 patients under the age of 18 years. On presentation the mean ESR was 69 (15 to 140) and the white cell count normal. Axial pain and weakness were the most common complaints. There was often a delay of more than a month to presentation. Five patients were HIV positive. Histological and microbiological examination confirmed tuberculosis in 40 patients. There were seven cervical cases, eight lumbar and 31 thoracic. Six patients had additional non-contiguous spinal involvement. There was one radicular syndrome and 30 patients had neurological deficits. Anterior and posterior surgery was done on 22 patients. There were eight anterior only procedures, seven posterior only, six costotransversectomies and three biopsies. In addition two revision anteriors were done. Allograft struts were used in 16 and autograft in 13. Anterior instrumentation was employed in 11, posterior in six and none in 11.

There were two deaths. Two grafts required early revision and one rotated but was accepted. Postoperative neurological recovery was noted from one day to 3 months, and typically by one month. All children regained normal neurological status.

Spinal tuberculosis is a common cause of neurological deficit and surgery has to suit the specific case. There is still a valuable role for surgery without instrumentation, especially in the paediatric group. Despite extensive destruction, one can expect full neurological recovery.

The aim of this study was to assess the use of early ambulatory halo-thoracic immobilisation in paediatric patients with spinal instability.

The case notes, radiographs and clinical findings at follow-up of 12 patients treated this way were reviewed. The mean age was 8.6 years (4 to 16). The aetiology was trauma in six, os odontoidium in one, tuberculosis in three, and Morquios syndrome and chronic granulomatous osteitis in one each. The instabilities were atlanto-axial rotatory subluxation in one patient, transverse ligament rupture in six, dens anomalies in two, anterior destruction by tuberculosis in two, and a dens fracture. The halo jackets were applied under general anaesthetic. In addition, posterior C1/2 fusions were performed in seven patients, posterior occipitocervical decompression and fusions in two, and posterolateral thoracotomies in two. No surgery was done on the patient with the dens fracture. Autograft was used in all cases except one posterior C1/2 fusion. This patient, who was HIV-positive, was the only one in whom union did not occur. There was one case of minor pin-tract sepsis. All patients mobilised in the halo jacket and, where possible, were managed as outpatients. Despite radiological nonunion in one patient, spinal stability was achieved in all.

Early ambulatory halo jacket immobilisation is a useful, safe and well-tolerated technique in the paediatric patient group.

Over 2 years, 14 patients with C1/2 instability underwent posterior transarticular screw fixation. Pathologies included atlanto-axial subluxation in five rheumatoid patients, atlanto-axial rotatory subluxation and an odontoid fracture in two patients with ankylosing spondylitis, nonunion of odontoid fractures in three patients, three transverse ligament injuries and one type-III odontoid fracture. This study aimed to assess the use of transarticular screw fixation in terms of technique, union rates and functional outcomes.

All operations were performed on a Relton-Hall frame with a Mayfield clamp and lateral fluoroscopy. The mean age of the eight men and six women was 48 years. The mean operation time was 112 minutes (65 to 225) and mean blood loss was 270 ml (150 to 700). Autologous posterior iliac crest bone graft was used in all patients. The procedure was aborted in one patient because of difficulty with reduction and screw angulation and in another because of excessive bleeding from the drill hole. Alternative fixation techniques were used in these two patients. All patients wore a Philadelphia collar postoperatively until stability was confirmed.

The time to radiological union was 8 to 10 weeks. Clinical outcomes revealed full ranges of flexion and extension in most patients, with a 50% decrease in cervical rotation. There were no neurological complications postoperatively. There was implant failure in one patient, with screw breakage evident at follow-up, but this patient went on to union without further intervention.

Transarticular screw fixation is an inexpensive, effective and safe technique for management of C1/2 instability.

The treatment of type-II traumatic spondylolisthesis of C2 remains controversial. We reviewed the outcome of 16 patients treated between 2001 and 2003.

As classified by Levine and Edwards, 14 patients sustained type-II fractures and two type-I injuries. There were no type-III injuries. All except one patient, who was injured playing rugby, were injured in motor vehicle accidents (four drivers, 10 passengers and one pedestrian). Eight patients had associated injuries. Thirteen patients were managed by means of a halo body jacket within 2 weeks of presentation for 5 to 9 weeks. One patient with a type-II injury was treated in an ABCO brace and those with type-I injuries in a Philadelphia collar.

All patients showed evidence of radiological union within 12 weeks (mean 7.5 weeks). Flexion/extension views revealed no instability. All patients regained full flexion and extension clinically, but five had some limitation of rotation. One patient removed the halo body jacket himself. There were no pin-tract or neurological complications. Mean follow-up time was 13.5 months (3 to 27). Four patients exhibited late disc space changes at C2/3 on radiographs.

Early patient mobilisation in a halo body jacket is an effective and safe management option for type-II C2 traumatic spondylolisthesis.

In the first year of existence of the Acute Spinal Injury Unit, 162 patients were admitted. A large number of injuries were the result of interpersonal violence. Case notes and radiographs of 49 consecutive patients with gunshot injuries to the spine were reviewed.

The mean age of the 38 male and 11 female patients was 27.5 years (15 to 51). The mean length of stay in the unit was 30 days (4 to 109). The 46 associated injuries were 11 fractures, 14 haemopneumothoraces, and one soft palate, nine visceral, two vascular, four brachial plexus, three oesophageal and two tracheal injuries. Non-spinal surgery was required in 17 patients. The spinal injury was complete in 38 patients and incomplete in eight. Three had no neurological deficit. The involved level was cervical in 13, thoracic in 24 and lumbar in 12. The spine was considered stable in 43 patients. Six patients underwent surgical stabilisation. In 11 patients the bullets were in the canal and were removed. One case of discitis was debrided. Complications included three deaths, discitis in three patients, pneumonia in six and pressure sores in six. The ASIA motor score improved marginally in nine patients and one patient had true functional improvement.

Gunshot injuries lead to a high incidence of permanent severe neurological deficit, but usually the spine remains mechanically stable. Most of the management revolves around the associated injuries and consequences of the neurological deficit.

Between 1964 and 2002, 26 pairs of conjoint twins were recorded at the Red Cross Hospital. The available radiographs and notes were reviewed, with specific attention to the incidence of spinal anomalies that result in scoliosis. Structural scoliosis was noted to occur only in the ischiopagus and pygopagus subsets, namely those joined by the pelvic outlet and the rump respectively. The abnormalities were largely those of failure of formation, with early onset of severe deformity. The hemi-vertebrae were often remote to the area of conjunction, mostly in the thoracic area. All six ischiopagi had vertebral abnormalities, with two of the four pygopagi demonstrating abnormalities. There were associated lower limb neurological abnormalities in the ischiopagi.

The association of conjoint twinning and vertebral anomaly is currently thought to be due to non-specific teratogenic insult with hypoxia. The fact that the ischiopagus and pygopagus are involved is important: these groups constitute up to 45% of survivors and are reported to have a longer life expectancy. Because they will later develop severe deformities, they need early active management.

Twenty-eight patients undergoing correction of thoraco-lumbar deformity were randomised to either the USS or Colorado 2 spinal instrumentation. Scoliosis was the deformity in 24 cases. Only once the surgical plan was decided upon was the instrumentation randomised, thus not influencing the use of anterior release or not.

Of the scoliotics, seven underwent anterior releases. The average duration was 107 minutes, blood loss 325 ml and number of levels 4.6 discs.

The USS group had 11 scoliosis cases. Nine were idiopathic, one neurofibromatosis and one neuromuscular. The average age at surgery was 18.7 years. The average number of levels fused was 11.4±1.6 (9–14). The average duration of surgery was 237±43.9 (180–330) minutes. The average blood loss was 2460±2204 (500–7500) ml. If the extreme blood loss of 7500 ml was excluded, then the average was 1900±1392 (500–4500). Costoplasties were performed in five cases. Only one case braced.

The Colorado 2 group had 13 scoliosis cases. Ten were idiopathic and three neuormuscular. The average age at surgery was 21.9 years. The average number of levels fused was 11±1.52 (9–14). The average duration of surgery was 198.3±34.9 (150–255) minutes. The average blood loss was 1766.7±863 (850–3800). Costoplasties were performed in five cases. Only one case braced.

Results: There was similar correction between the groups with Colorado 2 having an average of 52±16 (17–67)% and USS 62±17 (38–93)%. As regards instrumentation related failure, one USS hook cut out intra-operatively and needed to be replaced a level lower. In the Colorado group, there was also a laminar fracture. There were two screw cut outs, a hook pull out and two misplaced hooks in the Colorado group.

Conclusions: Both systems provided a similar amount of correction. There were more fixation point problems with the Colorado 2 group than the USS group. Some of these problems were related to insertion errors, but may have been due to migration during the correction process. This may indicate a benefit of the USS hook-screw fixation system.

Aiming to evaluate the efficacy and safety of instrumentation using only segmental pedicle screw fixation, we undertook a prospective study of 17 patients with idiopathic scoliosis who underwent corrective surgery in 1998 and 1999.

A total of 170 pedicle screws was inserted, 119 in the thoracic spine and 51 in the lumbar, extending from T2 to L5. The Cobb angle was measured on an erect anteroposterior radiograph postoperatively and at 6 and 12-month follow-up. Pedicle screw placement was assessed on the radiographs, and where there was concern about screw position, CT scan was performed.

Of the 170 pedicle screws, three were malpositioned lateral to the pedicle and one medial to the pedicle. One pedicle fractured during screw insertion, and three screws partially pulled out on the convex side of the curve at T3 to T5. At six months the mean Cobb angle correction was 53.6%. There were no neurological complications. Two cases required subsequent trimming of rods.

We believe fixation using only segmental pedicle screws is a safe method of correcting idiopathic scholastic deformities, but retain some reservations about the pull-out strength of the uppermost screws in the thoracic spine.