Background. Persistent low back and leg pain is a common and highly disabling musculoskeletal condition. Many patients seek the opinion of a neurosurgeon with a view to surgical intervention. Few data are available which document the experiences of patients at these consultations. Aims. To investigate the experiences of patients seeking a neurosurgical opinion for back and leg pain. Methods. 15 patients (Males 9 Females 6) were consented and recruited into this study and participated in an in-depth semi-structured interview about their experiences of the consultation. Interviews were recorded and transcribed. Transcribed data were read independently by two researchers and analysed using grounded theory. Results. Three subgroups of patients were identified from the interviews. Group 1: Patients that were offered surgery and described a positive experience. Group 2: Patients that were not offered surgery and described a positive experience. Group 3: Patients that were not offered surgery and described a negative experience. Analysis revealed a number of different themes pertaining to the experiences of each group. However, two overarching themes of i) meeting patients' expectations and ii) the factor of hope, emerged as significant contributors to their experience and were evident in all three subgroups. Conclusion. Findings identified the need to manage patient expectations in the consultation in order to provide a positive experience. Providing patients with hope who are not undergoing surgery, but who have an expectation for it, is likely to provide a more positive experience and therefore increased satisfaction with care. No conflicts of interest. Part funded by North East London Foundation Trust

Background. Criticisms about overuse of MRI in low back pain are well documented. Yet, with the exception of suspicion of serious pathology, little is known about factors that influence clinicians' preference for MRI. We investigated the factors associated with physiotherapists' preference for MRI for patients consulting with benign low back and leg pain (LBLP) including sciatica. Methods. Data were collected from 607 primary care patients consulting with LBLP and assessed by 7 physiotherapists, in the ATLAS cohort study. Following clinical assessment, physiotherapists documented whether he/she wanted the patient to have an MRI. Factors potentially associated with clinicians' preference for imaging were selected a priori, from patient characteristics and clinical assessment findings. A mixed-effect logistic regression model examined the associations between these factors and physiotherapists' preference for MRI. Results. Physiotherapists expressed a preference for MRI in 32% (196/607) of patients, of whom 22 did not have a clinical diagnosis of sciatica (radiculopathy). Factors associated with preference for MRI included; clinical diagnosis of sciatica (OR 4.23: 95% CI 2.29,7.81), greater than 3 months pain duration (OR 2.61: 95% CI 1.58,4.30), high pain intensity (OR 1.24: 95%CI 1.11,1.37), patient's low expectation of improvement (OR 2.40: 95% 1.50,3.83), physiotherapist's confidence in the diagnosis (OR 1.19: 95% CI 1.07,1.33) with greater confidence associated with higher probability of preference for MRI. Conclusion. A clinical diagnosis of sciatica and longer symptom duration were most strongly associated with physiotherapists' preference for MRI. Given current best practice guidelines, these appear to be justifiable reasons for wanting patients to have an MRI. Conflicts of interest: None. Funding. SE was supported through an NIHR internship linked to an NIHR Research Professorship awarded to NEF (RP-01-015). NEF is an NIHR Senior Investigator. KK is supported through a HEFCE Senior Clinical Lecturer award. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the NIHR, NHS or the Department of Health

Background. 60% of back pain patients report pain radiation in the leg(s), which is associated with worse symptoms and poorer recovery. The majority are treated in primary care, but detailed information about them is scarce. The objective of this study is to describe the characteristics of patients with back and leg pain-seeking treatment in primary care. Methods. Adult patients consulting their GP with back and leg pain were invited to the study. Participants completed questionnaires including sociodemographic, physical and psychosocial measures. They also underwent standardised clinical assessments by physiotherapists, and received an MRI scan. Results. 609 patients participated with 67.5% reporting pain below the knee. 62.6% were female, sample mean (SD) age 50.2 (13.9). 367 (60.7%) were in paid employment with 39.7% reporting time off work. Mean disability (RMDQ) was 12.7 (5.7) and mean pain intensity was 5.6 (2.2) and 5.2 (2.4) for back and leg respectively. Mean sciatica bothersomeness index (SBI) score was 14.9 (5.1). 74.2% (452/609) were clinically diagnosed as having sciatica. Patients in the sciatica group reported significantly higher levels of leg pain and SBI scores, leg pain worse than back pain and pain below the knee. Neuropathic pain was more prevalent in patients with referred leg pain. Conclusion. This primary care cohort reported high levels of disability and pain. Three quarters were diagnosed with sciatica. Follow-up of this cohort will investigate the prognostic value of their baseline characteristics. This abstract summarises independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research Programme (Grant Reference Number RP-PG-0707-10131). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. This abstract has not been previously published in whole or substantial part nor has it been presented previously at a national meeting. Conflicts of interest: No conflicts of interest. K. Konstantinou is supported by a HEFCE/NIHR Senior Clinical Lectureship. KM Dunn is supported by the Wellcome Trust (083572)

Introduction

Changes in the central nervous system (CNS) pathways controlling trunk and leg muscles in patients with low back pain and radiculopathy have been observed and this study investigated whether surgery impacts upon these changes.

Aims. To provide normative data that can assess spinal-related disability and the prevalence of back or leg pain among adults with no spinal conditions in the UK using validated questionnaires. Methods. A total of 1,000 participants with equal sex distribution were included and categorized in five age groups: 20 to 29, 30 to 39, 40 to 49, 50 to 59, and 60 to 69 years. Individuals with spinal pathologies were excluded. Participants completed the Scoliosis Research Society-22 (SRS-22r), visual analogue scale (VAS) for back/leg pain, and the EuroQol five-dimension index (EQ-5D/VAS) questionnaires, and disclosed their age, sex, and occupation. They were also categorized in five professional groups: doctors, nurses, allied health professionals, office workers, and manual workers. Results. The mean age of all participants was 43.8 years (20 to 69). There was no difference in the SRS-22r, EQ-5D, or VAS scores among male and female participants (p > 0.05). There was incremental decrease in SRS-22r total scores as the age increased. The mean EQ-5D index score (0.84) ranged little across the age groups (0.72 to 0.91) but reduced gradually with increasing age. There was difference between the SRS-22r total score (4.51), the individual domain scores, and the EQ-5D score (index: 0.94 and VAS: 89) for the doctors’ group compared to all other occupational categories (p < 0.001). Doctors had a younger mean age of participants, which may explain their improved spinal health. There was no difference in the total or sub-domain SRS-22r and EQ-5D scores between the other four occupational groups. Conclusion. This study provides the first normative data for the SRS-22r, EQ-5D, and VAS for back/leg pain questionnaires among adults in the UK. We recorded an excellent correlation between the three assessment tools with individuals who reported less back and leg pain having better quality of life and greater function. The participants’ age, rather than their sex or profession, appears to be the major determinant for spinal health and quality of life. Cite this article: Bone Jt Open 2022;3(2):130–134

Aims. We compared decompression alone to decompression with fusion surgery for lumbar spinal stenosis, with or without degenerative spondylolisthesis (DS). The aim was to evaluate if five-year outcomes differed between the groups. The two-year results from the same trial revealed no differences. Methods. The Swedish Spinal Stenosis Study was a multicentre randomized controlled trial with recruitment from September 2006 to February 2012. A total of 247 patients with one- or two-level central lumbar spinal stenosis, stratified by the presence of DS, were randomized to decompression alone or decompression with fusion. The five-year Oswestry Disability Index (ODI) was the primary outcome. Secondary outcomes were the EuroQol five-dimension questionnaire (EQ-5D), visual analogue scales for back and leg pain, and patient-reported satisfaction, decreased pain, and increased walking distance. The reoperation rate was recorded. Results. Five-year follow-up was completed by 213 (95%) of the eligible patients (mean age 67 years; 155 female (67%)). After five years, ODI was similar irrespective of treatment, with a mean of 25 (SD 18) for decompression alone and 28 (SD 22) for decompression with fusion (p = 0.226). Mean EQ-5D was higher for decompression alone than for fusion (0.69 (SD 0.28) vs 0.59 (SD 0.34); p = 0.027). In the no-DS subset, fewer patients reported decreased leg pain after fusion (58%) than with decompression alone (80%) (relative risk (RR) 0.71 (95% confidence interval (CI) 0.53 to 0.97). The frequency of subsequent spinal surgery was 24% for decompression with fusion and 22% for decompression alone (RR 1.1 (95% CI 0.69 to 1.8)). Conclusion. Adding fusion to decompression in spinal stenosis surgery, with or without spondylolisthesis, does not improve the five-year ODI, which is consistent with our two-year report. Three secondary outcomes that did not differ at two years favoured decompression alone at five years. Our results support decompression alone as the preferred method for operating on spinal stenosis. Cite this article: Bone Joint J 2024;106-B(7):705–712

Aims. To study the associations of lumbar developmental spinal stenosis (DSS) with low back pain (LBP), radicular leg pain, and disability. Methods. This was a cross-sectional study of 2,206 subjects along with L1-S1 axial and sagittal MRI. Clinical and radiological information regarding their demographics, workload, smoking habits, anteroposterior (AP) vertebral canal diameter, spondylolisthesis, and MRI changes were evaluated. Mann-Whitney U tests and chi-squared tests were conducted to search for differences between subjects with and without DSS. Associations of LBP and radicular pain reported within one month (30 days) and one year (365 days) of the MRI, with clinical and radiological information, were also investigated by utilizing univariate and multivariate logistic regressions. Results. Subjects with DSS had higher prevalence of radicular leg pain, more pain-related disability, and lower quality of life (all p < 0.05). Subjects with DSS had 1.5 (95% confidence interval (CI) 1.0 to 2.1; p = 0.027) and 1.8 (95% CI 1.3 to 2.6; p = 0.001) times higher odds of having radicular leg pain in the past month and the past year, respectively. However, DSS was not associated with LBP. Although, subjects with a spondylolisthesis had 1.7 (95% CI 1.1 to 2.5; p = 0.011) and 2.0 (95% CI 1.2 to 3.2; p = 0.008) times greater odds to experience LBP in the past month and the past year, respectively. Conclusion. This large-scale study identified DSS as a risk factor of acute and chronic radicular leg pain. DSS was seen in 6.9% of the study cohort and these patients had narrower spinal canals. Subjects with DSS had earlier onset of symptoms, more severe radicular leg pain, which lasted for longer and were more likely to have worse disability and poorer quality of life. In these patients there is an increased likelihood of nerve root compression due to a pre-existing narrowed canal, which is important when planning surgery as patients are likely to require multi-level decompression surgery. Cite this article: Bone Joint J 2021;103-B(1):131–140

Aims

Cauda equina syndrome (CES) can be associated with chronic severe lower back pain and long-term autonomic dysfunction. This study assesses the recently defined core outcome set for CES in a cohort of patients using validated questionnaires.

Purpose and background. Although low back pain (LBP) with leg pain, is considered by most a poor prognostic indicator, it is at the same time believed to have a favourable natural resolution, and is often treated along similar lines to non-specific LBP, in line with current guidelines. It is unclear whether patients with LBP and leg pain are a distinct subgroup that might benefit from early identification and targeted interventions. We set out to investigate the impact of LBP with leg pain on health outcomes and health resources compared with that of LBP alone, and to explore which factors contribute to the observed disability outcomes. Methods. A systematic literature search of all English language peer reviewed publications was conducted using Medline, EMBASE, and CINAHL for the years 1994 to 2009. Results. Of the 89 papers retrieved, 9 were included in the review. The heterogeneity of data allowed only for narrative analysis of findings. All studies reported worsening baseline health status in terms of poorer self-assessment and increasing use of health care the further the radiation of leg pain. Differences in quality of life measures were higher for physical than for mental health dimensions. Pain and disability outcome at follow up assessment appeared to be less favourable in this group than for individuals with LBP alone. Conclusion. LBP with leg pain is associated with poorer health outcomes and increased use of health resources. These findings argue for early identification of these cases by health care professionals and for pursuing effective treatments rather than simply treating similarly to non-specific LBP

Aims. To determine the value of scoliosis surgery, it is necessary to evaluate outcomes in domains that matter to patients. Since randomized trials on adolescent idiopathic scoliosis (AIS) are scarce, prospective cohort studies with comparable outcome measures are important. To enhance comparison, a core set of patient-related outcome measures is available. The aim of this study was to evaluate the outcomes of AIS fusion surgery at two-year follow-up using the core outcomes set. Methods. AIS patients were systematically enrolled in an institutional registry. In all, 144 AIS patients aged ≤ 25 years undergoing primary surgery (median age 15 years (interquartile range 14 to 17) were included. Patient-reported (condition-specific and health-related quality of life (QoL); functional status; back and leg pain intensity) and clinician-reported outcomes (complications, revision surgery) were recorded. Changes in patient-reported outcome measures (PROMs) were analyzed using Friedman’s analysis of variance. Clinical relevancy was determined using minimally important changes (Scoliosis Research Society (SRS)-22r), cut-off values for relevant effect on functioning (pain scores) and a patient-acceptable symptom state (PASS; Oswestry Disability Index). Results. At baseline, 65 out of 144 patients (45%) reported numerical rating scale (NRS) back pain scores > 5. All PROMs significantly improved at two-year follow-up. Mean improvements in SRS-22r function (+ 1.2 (SD 0.6)), pain (+ 0.6 (SD 0.8)), and self-image (+ 1.1 (SD 0.7)) domain scores, and the SRS-22r total score (+ 0.5 (SD 0.5)), were clinically relevant. At two-year follow-up, 14 out of 144 patients (10%) reported NRS back pain > 5. Surgical site infections did not occur. Only one patient (0.7%) underwent revision surgery. Conclusion. Relevant improvement in functioning, condition-specific and health-related QoL, self-image, and a relevant decrease in pain is shown at two-year follow-up after fusion surgery for AIS, with few adverse events. Contrary to the general perception that AIS is a largely asymptomatic condition, nearly half of patients report significant preoperative back pain, which reduced to 10% at two-year follow-up. Cite this article: Bone Joint J 2022;104-B(2):265–273

Pain catastrophising is an adverse coping mechanism, involving an exaggerated response to anticipated or actual pain. The purpose of this study was to investigate the influence of pain ‘catastrophising’, as measured using the pain catastrophising scale (PCS), on treatment outcomes after surgery for lumbar spinal stenosis (LSS). A total of 138 patients (47 men and 91 women, mean age 65.9; 45 to 78) were assigned to low (PCS score < 25, n = 68) and high (PCS score ≥ 25, n = 70) PCS groups. The primary outcome measure was the Oswestry Disability Index (ODI) 12 months after surgery. Secondary outcome measures included the ODI and visual analogue scale (VAS) for back and leg pain, which were recorded at each assessment conducted during the 12-month follow-up period. The overall changes in the ODI and VAS for back and leg pain over a 12-month period were significantly different between the groups (ODI, p < 0.001; VAS for back pain, p < 0.001; VAS for leg pain, p = 0.040). The ODI and VAS for back and leg pain significantly decreased over time after surgery in both groups (p < 0.001 for all three variables). The patterns of change in the ODI and VAS for back pain during the follow-up period significantly differed between the two groups, suggesting that the PCS group is a potential treatment moderator. However, there was no difference in the ODI and VAS for back and leg pain between the low and high PCS groups 12 months after surgery. . In terms of minimum clinically important differences in ODI scores (12.8), 22 patients (40.7%) had an unsatisfactory surgical outcome in the low PCS group and 16 (32.6%) in the high PCS group. There was no statistically significant difference between the two groups (p = 0.539). . Pre-operative catastrophising did not always result in a poor outcome 12 months after surgery, which indicates that this could moderate the efficacy of surgery for LSS. Cite this article: Bone Joint J 2015;97-B:1546–54

Background. PROMs have become an integral assessment tool of clinical effectiveness and patient satisfaction. To date, PROMs for lumbar discectomy are not an NHS requirement, although voluntary collection via the British Spine Registry is encouraged. Despite this, PROMs for day case microdiscectomy is scarcely reported. We present PROMs for day case microdiscectomy at Lancashire Teaching Hospitals. Aims. 1). To review PROMs to quantify leg pain, back pain, EQ5D and ODI scores. 2). Evaluate PROMs data collection compliance. Methods. We studied PROMs data, taken prospectively as part of routine clinical care for all patients who underwent single level day case microdiscectomy between January 2013 to December 2015. PROMs included VAS for back and leg pain, EQ5D and ODI scores. Preoperative PROMs were compared to all available postoperative PROMs at 3 months, 6 months, 12 months and 24 months. Paired student T-tests were used to compare preoperative to postoperative scores. Results. Preoperative PROMs were recorded for 132 patients. Postoperative PROMs were recorded for 48 patients at 3 months, 51 patients at 6 months, 37 patients at 12 months and 15 patients at 24 months. Significant postoperative improvements (p<0.05) were found at all time points for back pain, leg pain, EQ5D and ODI, with the exception EQ5D at 24 months (p = 0.10). Conclusion. There was significant improvement in VAS back and leg scores, as well as ODI scores over 24 months. Further work is needed to improve compliance with postoperative PROMs and to optimise the benefit of these health assessment tools. No conflicts of interest. No funding obtained

The aim of this study is to review the functional outcome of the patients treated with Posterior Lumbar Interbody Fusion for FBSS. This is a retrospective review of prospectively collected data of 39 patients diagnosed with FBSS and treated with PLIF between June 2000 and December 2008 by the senior author in our unit. Pain and function were evaluated by VAS for Back (VAS-BP) & leg pain (VAS-LP), Oswestry disability index (NDI) and SF-36 questionnaires, and were completed pre- & post-operatively. There were 39 patients (20 women & 19 men) and mean age at operation was 47.3 years (range of 32 to 76.1 years). Mean duration of follow-up was 39.14 months (range 5.21 -73.5 months). Thirty-one patients were diagnosed as Post laminectomy syndrome and 8 patients as post-discectomy syndrome. The mean pre and post-operative ODI values were 54.13 and 29.14 respectively. The mean pre-operative VAS back and leg pain scores were 7.38 and 6.51 respectively. The mean post-operative VAS for back and leg pain scores were reduced to 4.05 (Pre-op:7.38) and 3.69 (Mean pre-op 6.51)respectively. The mean preoperative SF-36 bodily pain component score was 27.42 and the mean postoperative score was 40.50. Four patients had uncomplicated dural tears that resolved completely. Two patients had superficial wound infection that resolved with oral antibiotics. PLIF is one of the safe and effective treatment option for FBSS and it has shown good results in our series

Lumbar fusion remains the gold standard for the treatment of discogenic back pain. Total disc replacement has fallen out of favor in many institutions. Other motion preservation alternatives, such as nucleus replacement, have had limited success and none are commercially available at this time. Two prospective, nonrandomized multicenter studies of lumbar disc nucleus replacement using the PerQdisc 2.0 nucleus replacement device in patients with lumbar discogenic back pain. Early clinical results are presented. A total of 16 patients from 4 international sites (Germany, Paraguay, Canada and Belgium) were enrolled in the trial between May 2019 and February 2021. Data collection points include baseline and postoperatively at 1, 2, 6, and 12 months. Clinical outcome measures were obtained from the Visual Analog Scale (VAS) for back and leg pain, Oswestry Disability Index (ODI), SF-12V2, Analgesic Score (AS), and radiographic assessments. Prospectively gathered data on patient reported outcomes, neurological outcome, surgical results, radiological analysis, and any adverse events. 16 patients had successful implantation of the device. There have been no expulsions of the device. Early postoperative results are available in 13/16 patients at 6 months and 11/16 patients at 12 months. There have been 4 (25%) revision surgeries 3–12 months post implantation between the two trials. 12 of 13 (92%) patients had Minimal Clinically Important Difference (MCID) in ODI at 6 months and 10 of 11 (91%) at 12 months. Mean decrease in ODI from baseline to 12 months was 44.8. At 12 months 8 (73%) patients are not taking pain medication, 1 (9%) patient is taking a narcotic for pain management. 73% of patients are working without restrictions at 12 months post implant. Early clinical and technical results are encouraging. Long term follow up is essential and is forthcoming. Additional patient recruitment and data points are ongoing. FDA/Drug Status Investigational/Not approved

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). Materials and Methods. We conducted a randomised clinical pilot trial of 40 patients who were scheduled to undergo a TLIF procedure at one or two levels between L2 and L5. The Oswestry disability index (ODI), EuroQoL-5D, and back and leg pain were determined pre-operatively, and at three, six, and 12 months post-operatively. Fusion rates were assessed by thin slice CT at three months and by functional radiography at 12 months. Results. At final follow-up, one patient in each group had been lost to follow-up. Two patients in each of the PEEK and TiPEEK groups were revised for pseudarthrosis (p = 1.00). The rate of complete or partial fusion at three months was 91.7% in both groups. Overall, there were no significant differences in ODI or in radiological outcomes between the groups. Conclusion. Favourable results with identical clinical outcomes and a high rate of fusion was seen in both groups. The titanium coating appears to have no negative effects on outcome or safety in the short term. A future study to determine the effect of titanium coating is warranted. Cite this article: Bone Joint J 2017;99-B:1366–72

To determine if the term “back pain” has uniform meaning to spinal surgeons. A survey of specialists attending an international meeting on spinal surgery. Participants were shown 5 schematic pain drawings and then asked to categorize the pain as either back or leg pain. An international cohort of neurosurgeons, orthopaedic surgeons and trauma surgeons (n=104) attending a European spinal meeting. 67% of participants were orthopaedic surgeons and 22% neurosurgeons. 42% were in full time spinal practice. 50% had been in independent practice for 7 years or more. There was no statistical difference in the responses of neuro- and orthopaedic surgeons (Fisher's test, p>0.05). The more rostral the pain, the more likely it was to be deemed “back pain”. However, unilateral pain was more likely to be deemed “leg pain” than its bilateral symmetrical equivalent no matter how rostral the distribution. Unilateral mid-lumbar pain was considered “back pain” by 48%, symmetrical bilateral mid-lumbar pain in 87%. Pain in the buttocks was considered “back pain” in 50% whether unilateral or bilateral. This study demonstrates significant discrepancy in what is considered to be back pain and leg pain by a broad spectrum of spinal surgeons. Back pain and leg pain are often investigated and managed in different ways. This differentiation is difficult to justify until we know the answer to the question, what is back pain?

Background and purpose. Modic changes (MC) are a risk factor for development of chronic low back pain (CLBP). There is no agreement about the cause of inflammation in MC, but autoimmunity has been suggested. The aim of the study was to investigate whether treatment with lactic acid bacteria for 100 days was associated with change of disability and pain, via a change in the gut microbiota inducing a change in the immune system, in patients with CLBP and type 1 MC during one year follow-up. Methods. Eighty-nine patients with CLBP and type 1 MC were randomized to receive either one capsule Lactobacillus Rhamnosis GG or placebo capsules twice daily for 100 days. Results. Missing values at one year were 4% and 3% in the disability and pain variables, respectively. The predefined outcomes disability and back and leg pain only changed little during follow-up with no statistically significant differences between groups. At one year, back pain had decreased by 1.1 more on a 0–10 scale (95% CI 0.20- 1.97) in the experimental group than in the control group. There were no differences regarding other predefined outcomes, i.e. global effect or percentage with minimal disability at one year. Nine percent of the patients reported gastrointestinal side-effects without difference between groups. Conclusions. No differences were found between groups regarding the predefined outcomes. Overall, the study confirmed that CLBP with MC1 is a grave back pain disorder, with little tendency to improvement. During follow-up, disability of the whole cohort was reduced by just 17%. Conflicts of interest: No conflicts of interest. Sources of funding: The study has been supported by The Danish Rheumatism Association and Peter and Helga Kornings Fond

The prevalence of degenerative spondylolisthesis (DS) increases with age. With an ageing population there will be increasing demands for adult deformity surgery, with associated significant financial and complication costs. The prevalence of lytic spondylolisthesis (LS) is 6–8%. Our clinical observation is that it is extremely rare to see LS in the presence of DS and therefore the objective was to formally describe the prevalence of LS in combination with DS to assess the hypothesis that 6–8% of patients with DS should also have LS. If this is not the case it may further our understanding of the pathogenesis of DS, which could aid in future prevention or treatment. A retrospective review of erect lateral lumbar radiographs demonstrating lumbar spondylolisthesis was performed. Radiographs were identified and analysed on the hospital Synapse Picture Archiving and Communication System (PACS). Search criteria were radiographs requested by primary care and patients aged over 60. 101 patients with spondylolisthesis were identified. 89% were requested for back or leg pain. There were 89 patients with DS (69.7% women) and 12 with LS (83% men). The average age of DS and LS patient was 75 and 70 respectively (not significant). There were no cases found with both DS and LS. This was significantly different to the expected amount of 6% (p=0.03). The level of DS was at L3/4 in 11.2% (n=10), L4/5 in 79.8% (n=71) and L5/S1 in 16.9% (n=15). 2 levels were involved in 7 patients. 94.4% (n=84) demonstrated a Meyerding grade 1 slip and 5.6% (n=5) grade 2 slip. For LS the slipped level was at L5/S1 in all cases. 66.7% (n=8) had a grade 1 slip and 33.3% (n=4) a grade 2 slip. We found no cases of lytic spondylolisthesis in the presence of degenerative spondylolisthesis. We hypothesis that the presence of spondylolysis or lytic spondylolisthesis may be protective against development of degenerative spondylolisthesis. More work is needed to explore this further

Background. Degenerative spondylolisthesis (DS) with stenosis is now typically treated by decompression and instrumented fusion. This treatment method does produce predictable results at the spondylolisthetic level, but later stenosis will occur commonly at the adjacent level due to the rigidity of the construct. Pedicle screw fusion may also be a significantly invasive procedure for an elderly patient. Aim. To evaluate the clinical potential of a new, non-screw based, posterior dynamic flexion-restricting stabilization system (FRSS). Method. 17 patients (15f, 2m; mean age 68 (45-78yr)) presenting with leg pain, with or without low back pain, and MR evidence of spinal stenosis with DS were treated by uni- or bilateral laminotomy and FRSS. Microdiscectomy was performed for one patient with a concomitant disc prolapse. The FRSS was placed at L4/5 in 13 patients and at L3/4 in four. Results. Follow up data was available for 12 patients at 3 months and 9 patients at 6 months. At 3 months the mean pain scores (VAS) for both back and leg pain (p<0.05) and ODI (>10 point) had improved and 82% were satisfied. Three patients had adverse events unrelated to the device or procedure. At 6 months the improvements were maintained in 8 patients. One complained of transient leg neuralgia (78% overall group satisfaction). There was no evidence of vertebral translation on flexion radiography. Mean blood loss at surgery was 220ml (50-1400ml) and instrumentation time 23min (10-54min). Discussions and Conclusion. Early data demonstrates good clinical outcomes in patients with DS treated with decompression and FRSS. Further follow up is necessary to evaluate whether stabilization with the FRSS can help to maintain the benefits of decompression over the longer-term. REC: 10/MRE00/9

Background. The relationship between obesity and cauda equina syndrome (CES) has not been previously evaluated or defined. Aim. The purpose of this study was to determine the effect of body habitus on the presentation and outcome of cauda equina syndrome. Study Design. Single-centre case series. Methods. A retrospective analysis was performed on 40 patients admitted with cauda equina syndrome. Data was collected regarding patient demographics, body mass index (BMI), co-morbidities, onset & mode of presentation and speed of functional recovery following surgery. Results. There were 18 males and 22 females with an overall average age of 38.9 years. The average height was 167 cm, and the average weight was 95.3 kg, giving an average BMI of 30.3 Kg/m2. 80% of patients were considered overweight (BMI 25-29.5) or obese (BMI >30). The average duration of back or leg pain prior to presentation was 4.2 years for the obese group and 1.3 years for the non-obese group. Bilateral sciatica, urinary incontinence and dense peri-anal numbness were the predominant presenting features in the obese group. Onset of symptoms was fast and rapidly evolving in the non-obese group compared to the obese group. In the non-obese group, 71% underwent surgery within 24 hrs as opposed to 31% in the obese group. There was correlation between increasing BMI and increased rate of surgical complications. Recovery of motor and sensory function appeared to occur more quickly in the non-obese compared to the obese group. Recovery of bladder continence was 83% in non-obese patients and 69% in the obese group at 6 months. Conclusion. This is the first study exploring the impact of body mass index on CES presentation and outcome. Specific care in establishing an early diagnosis in obese individuals is imperative for timely intervention