Introduction

Recently published results suggest insertion of shorter screws in L5/S1 stand-alone anterior interbody fusion, fearing S1 nerve root violation. However, insertion of shorter screws led to screw fixation failure and new onset of S1 body fractures.

Purpose: To report long-term results (with a minimum follow-up of 13 years) of GR construct [Luque-trolley (LT)] in EOS, to identify factors predictive of curve progression and to establish the timing of definitive fusion.

Method: The study cohort consisted of 37 patients (22M & 15F) who had primary LT between 1983–1995 were reviewed. Group I: 7 patients had LT alone and Group II: 30 had LT with convex fusion. Cobb at initial presentation, after first surgery, before definitive fusion and at the latest follow-up was recorded. Other radiological curve parameters recorded were rib spinal angle difference (RSAD), end vertebral tilts (EVT), apical vertebral rotation (AVR) and T1-S1 length. Complications with respect to development of junctional/apical kyphosis, implant failure, pseudoarthrosis (PA), sagittal/coronal profile and instrumented spinal segment growth at maturity were evaluated.

Results: The mean age at definitive fusion for study cohort was 12.5 years. Group I: Mean age at first surgery was 7.4 years (3.3–9.5y). Mean pre-op Cobb angle of primary curve was 600 (310–710) which was corrected to 280 (200–360). They underwent definitive segmental spinal instrumentation(SSI) with fusion at 13.9 years (9.8–15.1y) when the curve had worsened to 480 (400–650). Group II: Mean age at index surgery was 3.6 years (1.6–8.8y). Mean pre-op Cobb of primary curve was 580 (300–900) which corrected to 300 (100–620). 16/30 patients underwent definitive SSI with fusion at 11.5 years (8.5–14.2y) when the curve deteriorated to 600 (530–770). Instrumented segmental spinal growth was 3.2cms (SD±1.45; range 1–5cms). 14/30 maintained their correction till skeletal maturity. JK was observed in 8 cases [proximal(3), distal(2) & apical(3)] which were corrected at the time of definitive SSI. There was a linear relationship between Cobb angle at definitive fusion with concaveRSA and upperEVT.

Conclusion: Correlation and regression statistics revealed predictive factors of curve progression to be concave RSA (®=0.91 & p=0.001) and upper EVT (®=0.81 & p=0.0004). Patients with high concave RSA and upper EVT should be closely monitored for deterioration. Spinal growth that exceeds the capacity of LT to elongate leads to apical kyphosis. Timing of definitive fusion is influenced by growth velocity, clinico-radiological factors and complications.

Aim: To evaluate morbidity and outcome associated with lumbar spine decompression for central spinal stenosis in the elderly compared with younger age groups.

Patients & Methods: Case notes review of patients with symptomatic and MRI proven central lumber canal stenosis, under the care of a single surgeon. The study population was 3 age groups: patients < 60 year of age (Group 1, n=19), patients between 61 and 79 years(Group 2, n=54), and > age of 80 years (Group 3, n=15).

The number of levels decompressed & grade of surgeon were noted.

Outcome data: Length of operation & hospital stay, blood loss, and intra and post operative complications. Subjective variables: Pain (VAS), walking distance, Oswestry Disability score (ODI) and patient satisfaction scores.

Results: The duration of operation (p< 0.05), and intra-operative complication rate (p< 0.025) was dependent on the seniority of the surgeon.

There was a statistically significant improvement in VAS score for leg pain (p< 0.05) and back pain (p< 0.05) after surgery for each group. The average walking distance improved by factor 5 in group 1 and 2 and by factor 2.5 in group 3 (p< 0.05)

Conclusions: Surgery for neurogenic claudication in the octogenarian is associated with a higher complication rate. The outcomes in this patient group is however comparable to younger patients.

Study Design: observational study over time

Objectives: 1. To investigate the effect of right and left radiculopathy on driver brake-reaction time (DBRT) 2. Determine the effect of selective nerve root block (SNRB) on DBRT

Summary of Background Data: DVLA guidelines for fitness to drive after orthopaedic procedures remain vague. DBRT has been assessed using different driving simulators in several surgical and non-surgical conditions. To date the effect of sciatica and SNRB on DBRT has not been studied.

Methods: DBRT s of 20 patients with sciatica (10 right, 10 left) were measured using a custom-built car simulator. Each patient was tested pre-SNRB, immediate post-SNRB, 2 and 6 weeks post-SNRB. As controls 20 age-matched normal subjects were tested once. Full departmental, institutional and ethical committee approval were obtained.

Results: The mean reaction time of the control group was 459 ms. The mean reaction times of the patients at different points of assessment were as follow:

Conclusions:

This study confirms the intuitive impression that patients with sciatica have prolonged DBRT compared to normal population. This represents an extra absolute increase in traveling distance of 2.4 meters in a 70 mph speed zone.

Objective: To report a consecutive series of patients who underwent staged reduction and fusion with the Magerl External Fixator and 360° fusion for high grade slips and spondyloptosis.

Design: Prospective observational study.

Patients & methods: There were 11 patients, average age 17 years (range 9–25 years).

All these patients had equal or greater than Meyerding grade III slips.

Clinical presentation included severe back pain with disability and a severe cosmetic deformity (including flexed knees, proptotic abdomen and loin creases).

The indications for surgery were pain relief and neurological symptoms/signs, and to improve the sagittal alignment.

Surgery consisted of first stage Gill procedure, L5 root decompression, and insertion of Schanz pins into L4 pedicles and ilium, and application of the fixateur-externe. Second stage consisted of gradual correction of kyphosis and translation (average 1 week duration). Third stage entailed anterior interbody fusion, removal of fixator and instrumented fusion L5 to sacrum.

Outcome measures: Functional out comes (pain scores [VAS], activities of daily living) cosmesis, complications (including neurologic status) and radiographic parameters.

Results: Average follow-up was 3 years and 3 months. Postoperatively none of these patients developed a neurological deficit. Imaging confirmed solid fusion in all patients. In terms of reduction, 1 patient failed to reduce (fusion in-situ) and 1 patient developed subsequent L4 on L5 spondylolisthesis. There was no case of permanent neurologic deficit.

Nine (82%) patients reported improved pain scores on the VAS, improved quality of life and cosmetic appearance.

There was significant reduction of the translation (in most cases to grade II) and correction of the lumbosacral kyphosis. All patients went on to a solid arthrodesis and there was no late loss of correction.

Conclusions: Staged reduction and Fusion not only improves a severe cosmetic deformity but also restores sagittal balance. We recommend this technique as there is negligible risk of neurological complications, and avoids fusion involving two motion segments.

Introduction We report the two-year clinical outcome of a prospective randomised trial comparing Femoral Ring Allograft (FRA) to a Titanium Cage (TC) in circumferential lumbar spinal fusion.

Methods 83 patients recruited to the study fulfilled strict entry requirements (> 6 months chronic discogenic low back pain, failure of conservative treatment, one or two-level discographically proven discogenic pain source). 38 patients were randomised to receive FRA, 45 patients were randomised to receive TC. Posterior stabilisation was achieved with translaminar or pedicle screws. Patients completed questionnaires including Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) and the Short-Form 36 (SF-36) pre-operatively and 6, 12 and 24 months post-operatively.

Results Results were available for all 83 patients with a mean follow-up of 26.5 months (range 24–75 months). Baseline demographic data (age, sex, smoking history, number of operated levels, pre-operative outcome measures) showed no statistical difference between groups (p< 0.05). For patients receiving the FRA, mean VAS (back pain) improved 2.0 points (p=0.01), mean ODI improved 14 points (p=< 0.01), and mean SF-36 scores improved by > 11 points in all domains (p< 0.03) except general health and emotional role. For patients receiving the TC, mean VAS improved 1.2 points (p=0.002), mean ODI improved 5 points (p=0.02); SF-36 improved significantly in only one of eight domains (bodily pain).

Discussion Clinical outcome following circumferential lumbar fusion with FRA readily achieves the accepted mean clinically important differences (MCID). Fusion with TC does not achieve the MCID. The use of TC for circumferential lumbar fusion appears not to be justified.

Background: Anterior scoliosis correctional surgery can result in screw pull out or pedicular fracture. This is more common in stiff curves where the instrumentation extends to the smaller, higher, thoracic levels. The fracture/intra-operative pull out usually occurs during the reduction maneuver. In all of our cases the curve was reduced in the standard cranial to caudal direction using a cantilever maneuver. We describe a salvage technique using circlage wires that can be used for this problem. We present seven cases and the final outcome.

Methods: The technique involves placing a longer screw into the damaged vertebrae so it protrudes 5mm proud. A 1.25mm circlage wire is then cut to length and passed around the tip of the screw. It is then looped in a figure of eight passed under the rod and tightened around the respective pedicle screw head. A case record and x- ray review of seven procedures performed was then carried out. The age of the patients was between 14 and 41 years (mean 20) at surgery. The pre-operative Cobb was between 72 and 43 (mean 58). One curve was flexible with a flexibility index of 70% but the remainder was stiffer (range 34%–40%). There was one thoracolumbar curve with a T11 fracture. All other curves were thoracic and the fracture levels were T5, T7, T7, T6+7, T6+7+8, and T6+7+8 respectively. Four out of seven were braced post operatively for three months. The Cobb angle over the instrumented levels immediately post surgery and at final follow up was measured. The technique was deemed to be successful if no significant loss of correction occurred.

Results: The technique held position in six out of seven of the subjects. The average loss of position in these patients was two degrees (range 0–4). In one subject the curve went from 28 degrees immediately post operatively to 38 degrees over 2 years. The four month post operative x ray showed no loss of position suggesting that this loss of position may not be due to the fracture. This patient remained pleased with his cosmetic result and went from 72 degrees pre operatively to 38 degrees at 2 year follow up.

Conclusion: Care should be taken in patients with stiff proximal curves. The use of larger 8mm screws may decrease pull out and consideration may be given to caudal to cranial reduction in some cases. Circlage wire rescue is a useful salvage procedure for inter-operative fracture or screw pull out during anterior scoliosis correction.

Purpose of study. To compare the cost and outcome of Intradiscal Elecrothermal Therapy (IDET) with fusion (anterior lumbar interbody fusion with posterior translaminar screws) at one year, in single level lumbar disc disease.

Methods. 49 patients were prospectively enrolled for IDET. The 49 fusion group patients had either a Syncage or Femoral Ring Allograft. All patients had at least 6 months of LBP with single level disease on MRI or positive discography.

Results. The two groups were demographically similar. Pre-treatment ODI, VAS and SF-36 for physical function were significantly worse in the fusion group (p< 0.05). At 1 year, IDET patients had clinically important improvement in ODI (47 to 37, p< 0.001), SF-36 pain (26 to 42, p< 0.001) and physical function (40 to 54, p< 0.001), with a significant drop in VAS (5.4 to 4.2, p=0.012). Fusion patients had clinically important improvement in ODI (54 to 44, p< 0.001) and SF-36 pain (25 to 37, p< 0.001) but not in physical function (32 to 39, p=0.08), with a significant improvement in VAS (7.2 to 5.7, p=0.001). Within 1 year, 11 patients in the IDET group had further interventions (4 nerve root blocks, 1 fusion, 2 disc replacements, 2 posterior interbody fusions) and 9 further procedures were carried out in the fusion group (2 epidurals, 1 facet injection, 4 wound washouts, 1 revision posterior instrumentation, 1 repair pseudomeningocoele). Cost per patient at 1year, including all secondary procedures, was £7,545 for fusion and £2,851 for IDET patients.

Conclusions. Fusion is substantially more expensive than IDET with comparable clinical outcome.

Recent years have seen the popularization of minimally invasive approaches to the spine.

However, the use of the balloon assisted retroperitoneal approach has not been widely described, moreover there has been no direct comparison between this mini-ALIF (anterior lumbar interbody fusion) and the conventional open method in the literature.

Comparison of peri and intra-operative parameters between the rnini-ALIF (using the balloon assisted dissector and Synframe retractor system) and the open midline approach for single and double level anterior lumbar interbody fusions in order to assess the efficacy of this procedure.

An independent retrospective evaluation of 35 patients who underwent single or double level ALIF under the care of the senior author at the University Hospital, Nottingham during the period from 1997 to 2000. The patients were split between those undergoing a mini-ALIF (balloon assisted retroperitoneal dissection) or the conventional approach via a larger midline incision. The groups were matched for age, sex and number of levels. Data was collated from the medical notes with regards to intra-operative blood loss, operative time, intra-operative complications, PCA requirements, time to mobilisation and length of hospital stay.

A statistically significant (p=0. 01) reduction in time to mobilisation (mean 2. 1 days vs 3. 9 days) and operative time (mean 175mins vs 265mins) was found for the single level mini-ALIF. This reflects the greater number of L5/SI fusions in this group. The number of vascular injuries was also greater in the approach to L4/5.

No difference was found between the two groups for double level procedures.

The immediate advantages of a less invasive approach both to the patient and hospital do not appear to be borne out by this study. Cosmesis was not assessed and the long term functional outcome awaits later confirmation.

Objective: A clear definition of cauda equina syndrome (CES) following herniated discs was not available from the literature. Some define CES as a total paralysis of the pelvic viscera1 while others consider any dysfunction as sufficient evidence of CES2. An extensive search of the literature also demonstrated a lack of a disease specific outcome measure for CES. We aimed to classify CES in the above spectrum and validate a new outcome score for CES.

Design and subjects: We present a retrospective study of 38 patients with a minimum of one-year follow up who presented with an acute cauda equina syndrome. We categorized the patients as complete or incomplete and further sub-classified them as acute or chronic. A total paralysis of the pelvic viscera was considered as complete. Presence of only dysfunction of the pelvic viscera was considered as incomplete. If the presenting episode plateaued within 24 hours or less of onset it was classified as acute and if it plateaued later than 24 hours it was considered as chronic.

Outcome measures: The new 17-item disease specific questionnaire was compared with the Oswestry Disability Index, SF36 and Urodynamic studies.

Results and conclusion: Of the patients studied, 44.7% were complete with acute onset, 21.1% were complete with chronic onset, 10.5% were incomplete with acute onset and 23.7% were incomplete with chronic onset. Outcome score matched the spectrum of our suggested classification.

Objective: This study investigates whether fixation down to lumbar spine only can prevent pelvic tilt compared to pelvic fixation, in the surgical treatment of Duchenne Muscular Dystrophy (DMD).

Design: Retrospective and prospective clinical outcome study, with long-term follow up.

Materials and Methods: Nineteen cases of DMD with scoliosis had early stabilisation (mean age 11.5 years, range 9–16) with sublaminar wires and rods, and pedicle screws up to the lumbar spine. This cohort was followed up for a mean 4.2 years (3–10 years). 31 cases in another centre had late stabilisation (mean age 14.5 years, range 10–17), with Luque rod and sublaminar wire fixation, and pelvic fixation using L-rod (22 cases) configuration or Galveston technique (9 cases) and were followed up for 4.6 years (0.5–11.5 years). Post-op morbidity, Cobb angle correction and pelvic obliquity data were collected retrospectively and prospectively for comparison.

Results: In the lumbar fixation group FVC was 58%, the mean Cobb angle and pelvic obliquity were 19.8° and 9° preoperative, 3.2° and 2.2° direct postoperative, and 5.2° and 2.9° at final follow up respectively. The mean estimated blood loss was 3.3 litres and average hospital stay 7.7 days. In the pelvic fixation group FVC was 44%, the mean Cobb angle and pelvic obliquity were 48° and 19.8° preoperative, 16.7° and 7.2° direct postoperative, and 22° and 11.6° at final follow up respectively. The mean blood loss (4.1 litres) and the average hospital stay (17 days) were significantly higher (p< 0.05) compared to the lumbar fixation group. The pelvic fixation group had higher complication rate at the lower end of fixation. No progression of the pelvic obliquity was noted in the lumbar fixation group during follow up

Conclusion: Lumbar fixation may be adequate for scoliosis in DMD, if the stabilisation is performed early, before the pelvis becomes tilted, and scoliosis becomes significant. The caudal pedicular fixation in the lumbar spine stops rotation of the spine around the rods, and prevent pelvic tilt to occur. Pelvic fixation may be necessary in presence of established pelvic obliquity and larger scoliosis, but is associated with higher morbidity and complications.

Objectives: Comparison of peri and intraoperative parameters between mini-ALIF (using balloon assisted dissector and Synframe retractor) and open midline approach for single and double level ALIF.

Methods: Independent, retrospective evaluation of 35 patients split between those undergoing the mini-ALIF or the conventional approach via larger midline incision. Groups matched for age, sex and number of levels. Operations performed at University Hospital, Nottingham between 1997 and 2000.

Outcome measures: Data collated for operative time, intraoperative blood loss, complications, PCA requirements, time to mobilisation and hospital stay.

Results: Statistically significant (p=0.01) reduction in operative time (175 vs 265mins) and time to mobilization (2.1 vs 3.9 days) found for single level mini-ALIF. Complications namely vascular injuries were almost equal in both groups. No difference was found between the two groups for double level procedures.

Conclusion: The immediate advantages of a less invasive approach both to the patient and the hospital do not appear to be borne out by this study. Cosmesis was not assessed and long term functional outcome awaits later review.

Objective: Determine the incidence of abnormal somatosensory evoked potentials (SSEP) in patients with ‘at risk’ spinal cords undergoing anterior spinal deformity surgery.

Design: A retrospective chart and SSEP trace review of cases between 1982–2001.

Subjects: Patients undergoing elective anterior spinal deformity surgery were included. Excluded were those with inadequate SSEP monitoring or no pre-operative MRI scan.

Outcome measures: Paraparesis due to cord ischaemia based on an abnormal SSEP trace, i. e. > 50% decrease in SSEP baseline amplitude +/− > 10% increase in latency¹.

Results: Partial data was available for 1982–1990, thus analysis was based on cases between 1990–2001.871 patients underwent elective anterior spinal deformity surgery, 11% were ‘at risk cords’; 2% demonstrated intraoperative SSEP changes. Post operative paraparesis ws found in 0.6%. Intra-operative changes were significantly more common in ‘at risk cords’ (chi-squared test = 30.3, df = 2; p< 0.005). No statistical difference in the incidence of paraparesis in normal cords vs ‘at risk’ cords.

Conclusions: Post operative neurological deficit is rare in anterior spinal deformity surgery. Significant SSEP changes do occur with ligation of segmental vessels, implying cord ischaemia. Therefore, for the ‘at risk cord’, these patients should be considered for spinal cord monitoring and temporary clamping of segmental vessels prior to their division

Objective: To demonstrate possible advantages of combined (motor and sensory) versus single modality (either motor or sensory) intraoperative spinal cord monitoring

Design: Retrospective and prospective clinical study

Materials and Methods: One hundred and twenty-six consecutive operations in 97 patients had peroperative monitoring the lower limb motor evoked potentials (MEPs) to multi- pulse transcranial electrical stimulation (TES), and tibial nerve somatosensory evoked potentials (SEPs). Seventy-nine patients had spinal deformity surgery, and eighteen had surgery for trauma, tumor or disc herniation

Results: Combined motor and sensory monitoring was successfully achieved in 104 of 126 (82%) operations. Monitoring was limited to MEPs alone in two, and SEPs alone in eighteen cases. Neither MEPs nor SEPs were obtainable in two cases with Friedreich’s ataxia. Significant evoked potentials (EP) changes occurred in one or both modalities in 16 patients, in association with instrumentation (10) or systemic changes (6). After appropriate remedial measures, SEPs recovered either fully or partially in all cases (8/8) and MEPs in 10/15. New neurodeficits developed post-operatively in six of the sixteen patients with abnormal EPs, including two in whom SEPs had either not changed or recovered fully after remedial measures. One patient developed S3–5 sensory loss despite full recovery of both SEPs and MEPs. Two patients without neurological consequences had persistent MEP changes. Normal MEPs (but not SEPs) at the end of the operation correctly predicted the absence of new motor deficits. There were no false negative MEP changes.

Conclusion: MEPs are more sensitive than SEPs, but may rarely raise false positive alarm. SEPs are unaffected by anaesthetics and can be monitored more frequently. Combined monitoring is safe, complimentary to each other, and increases sensitivity and predictivity of adverse neorological consequences. True incidence of false positive MEP or SEP changes are difficult to define. Remedial measures after monitoring changes may help cord ischaemia to recover and absence of neurological deficit, therefore, may not indicate a false positive monitoring change.