Aims. The aim of this study was to determine if positive Waddell signs were related to patients’ demographics or to perception of their quality of life. Patients and Methods. This prospective cross-sectional study included 479 adult patients with back pain from a university spine centre. Each completed SF-12 and Oswestry Disability Index (ODI) questionnaires and underwent standard spinal examinations to elicit Waddell signs. The relationship between Waddell signs and age, gender, ODI, Mental Component Score (MCS), and Physical Component Score (PCS) scores was determined. Results. Of the 479 patients, 128 (27%) had at least one positive Waddell sign. There were significantly more women with two or more Waddell signs than men. The proportion of patients with at least one positive Waddell sign increased with age until 55 years, and then declined rapidly; none had a positive sign over the age of 75 years. Functional outcome scores were significantly worse in those with a single Waddell sign (p < 0.01). With one or more Waddell signs, patients’ PCS and ODI scores indicated a perception of severe disability; with three or more Waddell signs, patients’ MCS scores indicated severe disability. With five Waddell signs, ODI scores indicated that patients perceived themselves as crippled. Conclusion. Positive Waddell signs, a potential indicator of central sensitization, indicated a likelihood of having functional limitations and an impaired quality of life, particularly in young women. Cite this article: Bone Joint J 2018;100-B:219–25

Background and purpose. Sleep disturbance is frequently reported by people with chronic low back pain (CLBP >12 weeks), but there is limited knowledge of their sleep quality compared to healthy people. While disturbed sleep influences patients' mood, quality of life and recovery, few studies have comprehensively investigated sleep in CLBP. This study investigated differences in sleep profiles of people with CLBP, compared to age- and gender matched controls over seven consecutive nights. Methods. Thirty-two consenting subjects (n=16 with CLBP, n=16 matched controls), aged 24-65 years (43.8% male) underwent an interview regarding sleep influencing variables (e.g. mattress firmness, caffeine consumption), completed the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Pittsburgh Sleep Diary, SF36-v2, Hospital Anxiety and Depression Scale, and CLBP measures (i.e. Oswestry Disability Index and Numerical Pain Scales), recorded seven consecutive nights of sleep in their home using actigraphy, and completed a Devices Utility Questionnaire. Results. Compared to controls, people with CLBP had significantly disturbed sleep on self-report measures (PSQI mean (SD) 10.9 (4.2); ISI mean 13.7 (7.6); Sleep Diary; p<0.001), but no significant differences on objective actigraphy (p>0.05). Actigraphy was found to be a user friendly sleep measure for use in the home environment (84.6%, n=11 CLBP; 73.3%, n=11 control). Conclusions. Self-rated sleep using a valid instrument should be routinely measured in LBP research and clinical practice. Further investigation of the relationship between patients' perception of their sleep quality and its objective measurement is warranted before actigraphy could be recommended as an objective outcome measure for the evaluation of sleep in this population

Purpose of study. Cauda Equina Syndrome (CES) is a surgical emergency. With Physiotherapists increasingly taking on first-contact and spinal triage roles, screening for CES must be as thorough and effective as possible. This study explores whether Physiotherapists are asking the correct questions, in the correct way and investigates their experiences when screening for this serious condition. Background. Thirty physiotherapists working in a community musculoskeletal service were purposively invited to participate in semi-structured interviews. Data was transcribed and thematically analysed. Methods and Results. All participants routinely asked bladder, bowel function and saddle anaesthesia screening questions although only 9 routinely asked about sexual function. Whether questions are asked in the correct way has never been studied. Sufficient depth of questioning was achieved by 63% of participants, 76% used lay terminology and 73% used explicit language. Only 43% framed the questions before asking them and only 16% combined all four dimensions. Whilst most participants (n = 25) felt comfortable asking general CES questions, 50% reported feeling uncomfortable when asking about sexual function. Issues around; gender, culture and language were also highlighted. Conclusion. Four main themes emerged from this study; i) Physiotherapists ask the right questions but frequently omit sexual function questions, ii) mostly, Physiotherapists ask CES questions in a way that patients understand however, there needs to be improvement in framing the context of the questions, iii) Physiotherapists generally feel comfortable with CES screening but there is some awkwardness surrounding discussion of sexual function and iv) Physiotherapists perceive there to be barriers to effective CES screening caused by culture and language. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained. Previously presented poster at BritSpine 2021 and VPUK 2021

Aims. The aims of this study were to determine the rates of surgical complications, reoperations, and readmissions following herniated lumbar disc surgery, and to investigate the impact of sociodemographic factors and comorbidity on the rate of such unfavourable events. Patients and Methods. This was a longitudinal observation study. Data from herniated lumbar disc operations were retrieved from a large medical database using a combination of procedure and diagnosis codes from all public hospitals in Norway from 1999 to 2013. The impact of age, gender, geographical affiliation, education, civil status, income, and comorbidity on unfavourable events were analyzed by logistic regression. Results. Of 34 639 operations, 2.7% (95% confidence interval (CI) 2.6 to 2.9) had a surgical complication, 2.1% (95% CI 2.0 to 2.3) had repeat surgery within 90 days, 2.4% (95% CI 2.2 to 2.5) had a non-surgical readmission within 90 days, and 6.7% (95% CI 6.4 to 6.9) experienced at least one of these unfavourable events. Unfavourable events were found to be associated with advanced age and comorbidity. Conclusion. The results suggest that surgical complications are less frequent than previously suggested. There are limited associations between sociodemographic patient characteristics and unfavourable events. Cite this article: Bone Joint J 2019;101-B:470–477

Aims. The purpose of this study was to investigate the prevalence of sarcopenia and to examine its impact on patients with degenerative lumbar spinal stenosis (DLSS). Patients and Methods. This case-control study included two groups: one group consisting of patients with DLSS and a second group of control subjects without low back or neck pain and related leg pain. Five control cases were randomly selected and matched by age and gender (n = 77 cases and n = 385 controls) for each DLSS case. Appendicular muscle mass, hand-grip strength, sit-to-stand test, timed up and go (TUG) test, and clinical outcomes, including the Oswestry Disability Index (ODI) scores and the EuroQol EQ-5D were compared between the two groups. Results. The prevalence of sarcopenia, as defined by hand-grip strength, was significantly higher in the DLSS group (24%) when compared with the age- and gender-matched control group (12%) (p = 0.004). In the DLSS group, the sarcopenia subgroup demonstrated inferior results for the TUG test and ODI scores when compared with the non-sarcopenia subgroup (p = 0.006 and p = 0.039, respectively) after adjusting for age and gender. Conclusion. This study demonstrated a higher prevalence of sarcopenia in patients with DLSS and highlighted its negative effect on clinical outcomes. Cite this article: Bone Joint J 2016;98-B:1093–8

Aims

Surgical approaches to cervical ossification of the posterior longitudinal ligament (OPLL) remain controversial. The purpose of the present study was to analyze and compare the long-term neurological recovery following anterior decompression with fusion (ADF) and posterior laminectomy and fusion with bone graft and internal fixation (PLF) based on > ten-year follow-up outcomes in a single centre.

Lumbar disc herniation (LDH) is uncommon in youth and few cases are treated surgically. Very few outcome studies exist for LDH surgery in this age group. Our aim was to explore differences in gender in pre-operative level of disability and outcome of surgery for LDH in patients aged ≤ 20 years using prospectively collected data. From the national Swedish SweSpine register we identified 180 patients with one-year and 108 with two-year follow-up data ≤ 20 years of age, who between the years 2000 and 2010 had a primary operation for LDH. Both male and female patients reported pronounced impairment before the operation in all patient reported outcome measures, with female patients experiencing significantly greater back pain, having greater analgesic requirements and reporting significantly inferior scores in EuroQol (EQ-5D-index), EQ-visual analogue scale, most aspects of Short Form-36 and Oswestry Disabilities Index, when compared with male patients. Surgery conferred a statistically significant improvement in all registered parameters, with few gender discrepancies. Quality of life at one year following surgery normalised in both males and females and only eight patients (4.5%) were dissatisfied with the outcome. Virtually all parameters were stable between the one- and two-year follow-up examination. LDH surgery leads to normal health and a favourable outcome in both male and female patients aged 20 years or younger, who failed to recover after non-operative management. Cite this article: Bone Joint J 2015;97-B:1675–82

Aims. Although we often encounter patients with an aortic aneurysm who also have diffuse idiopathic skeletal hyperostosis (DISH), there are no reports to date of an association between these two conditions and the pathogenesis of DISH remains unknown. This study therefore evaluated the prevalence of DISH in patients with a thoracic aortic aneurysm (AA). Patients and Methods. The medical records of 298 patients who underwent CT scans for a diagnosis of an AA or following high-energy trauma were retrospectively examined. A total of 204 patients underwent surgery for an AA and 94 had a high-energy injury and formed the non-AA group. The prevalence of DISH was assessed on CT scans of the chest and abdomen and the relationship between DISH and AA by comparison between the AA and non-AA groups. Results. The prevalence of DISH in the AA group (114/204; 55.9%) was higher than that in the non-AA group (31/94; 33.0%). On multivariate analysis, the factors of AA, male gender, and ageing were independent predictors of the existence of DISH, with odds ratios of 2.9, 1.9, and 1.03, respectively. Conclusion. This study revealed that the prevalence of DISH is higher in patients with an AA than in those without an AA, and that the presence of an AA significantly influenced the prevalence of DISH. Cite this article: Bone Joint J 2018;100-B:617–21

Aims. Magnetically controlled growing rod (MCGR) systems use non-invasive spinal lengthening for the surgical treatment of early-onset scoliosis (EOS). The primary aim of this study was to evaluate the performance of these devices in the prevention of progression of the deformity. A secondary aim was to record the rate of complications. Patients and Methods. An observational study of 31 consecutive children with EOS, of whom 15 were male, who were treated between December 2011 and October 2017 was undertaken. Their mean age was 7.7 years (2 to 14). The mean follow-up was 47 months (24 to 69). Distractions were completed using the tailgating technique. The primary outcome measure was correction of the radiographic deformity. Secondary outcomes were growth, functional outcomes and complication rates. Results. The mean Cobb angle was 54° (14° to 91°) preoperatively and 37° (11° to 69°) at the latest follow-up (p < 0.001). The mean thoracic kyphosis (TK) was 45° (10° to 89°) preoperatively and 42° (9° to 84°) at the latest follow-up. The mean T1–S1 height increased from 287 mm (209 to 378) to 338 mm (240 to 427) (p < 0.001) and the mean sagittal balance reduced from 68 mm (-76 to 1470) preoperatively to 18 mm (-32 to 166) at the latest follow-up. The mean coronal balance was 3 mm (-336 to 64) preoperatively and 8 mm (-144 to 64) at the latest follow-up. The mean increase in weight and sitting and standing height at the latest follow-up was 45%, 10% and 15%, respectively. The mean Activity Scale for Kids (ASKp) scores increased in all domains, with only personal care and standing skills being significant at the latest follow-up (p = 0.02, p = 0.03). The improvements in Cobb angle, TK and T1-S1 heights were not related to gender, the aetiology of the EOS, or whether the procedure was primary or conversion from a conventional growing rod system. A total of 21 children developed 23 complications at a rate of 0.23 per patient per year. Seven developed MCGR-specific complications. Complications developed at a mean of 38 months (3 to 67) after the initial surgery and required 22 further procedures. Children who developed a complication were more likely to be younger, have syndromic EOS, and have a single-rod construct (6.9 versus 9.3 years, p = 0.034). Conclusion. The progression of EOS can be controlled using MCGRs allowing growth and improved function. Younger and syndromic children are more likely to develop complications following surgery. Cite this article: Bone Joint J 2018;100-B:1187–1200

Introduction. Patients with recurrent low back pain (LBP) exhibit changes in postural control. Stereotypical muscle activations resulting from external perturbations include anticipatory (APAs) and compensatory (CPAs) postural adjustments. This study aimed to determine differences in postural control strategies (APAs and CPAs) between those with and without lumbar disc degeneration (LDD) and LBP. Methods. Ninety-seven subjects participated in the study (mean age 50 years (SD 12)). 3T MRI was used to acquire T2 weighted images (L1-S1). LDD was determined using Pfirrmann grading and LBP using the numerical rating scale (NRS). A bespoke perturbation platform was designed to deliver postural perturbations. Electrical activity was analysed from 16 trunk and lower limb muscles during four typical APA and CPA epochs. A Kruskal-Wallis H test with Bonferroni correction for multiple comparisons was conducted. Results. Four groups were identified; ‘no LDD no pain’ (n = 19), ‘LDD no pain’ (n =38), ‘LDD pain’ (n =35) and ‘no LDD pain’ (n = 5). There was no significant difference in age or gender between groups. Although, increased BMI was associated with LBP it did not correlate with significant findings. Significant differences in APAs and CPAs were observed between ‘LDD pain’ and ‘LDD no pain’ groups during predicted and unpredicted perturbations (p=0.009–0.049, r=0.31–0.43). Significant CPAs correlated with LBP (p=0.001–0.03) but did not correlate with LDD (p=0.22–0.94). Conclusion. Postural control strategies are different between those with LDD and pain and those without. Differences in compensatory strategy are associated with the presence of pain and not LDD. No conflicts of interest. Sources of Funding: Janet Deane is funded by an Allied Health Professional Doctoral Fellowship awarded by Arthritis Research U.K. (ARUK)

Aims. The aim of this study was to evaluate improvements in the quality and safety of paediatric spinal surgery following the implementation of a specialist Paediatric Spinal Surgical Team (PSST) in the operating theatre. Patients and Methods. A retrospective consecutive case study of paediatric spinal operations before (between January 2008 and December 2009), and after (between January 2012 and December 2013) the implementation of PSST, was performed. A comparative analysis of outcome variables including surgical site infection (SSI), operating time (ORT), blood loss (BL), length of stay (LOS), unplanned staged procedures (USP) and transfusion rates (allogenic and cell-saver) was performed between the two groups. The rate of complications during the first two postoperative years was also compared between the groups. Results. There were 130 patients in the pre-PSST group and 277 in the post-PSST group. The age, gender, body mass index (BMI), preoperative Cobb angle of the major curve and the number of levels involved were similar between the groups. There were statistically significant differences in SSI, ORT, LOS, allogenic blood transfusion volume (ABTV), and USPs between the groups. There was a 94% decrease in the rate of SSI's in the post-PSST group. Patients in the post-PSST group had a mean reduction in ORT of 53 minutes (. sd. 7.7) (p = 0.013), LOS by 5.4 days (. sd. 1.8) (p = 0.019), and ABTV by 226.3 ml (. sd. 28.4) (p < 0.001). There were significantly more USPs in the pre-PSST group (6.2%) compared with the post-PSST group (2.9%) (p = 0.001). Multivariate regression showed that the effect of PSST remained significant for ORT, LOS, BL, ABVT and cell-saver amount transfused (p = 0.0001). The odds of having a SSI were tenfold higher and the odds of receiving a blood transfusion were 2.4 times higher, respectively, in the pre-PSST group (p = 0.004 and p = 0.011). The rate of complications within the first two postoperative years was significantly higher in the pre-PSST group (13.1%) compared with the post-PSST group (4.3%) (p < 0.001). Conclusion. The implementation of a PSST in the operating theatre significantly improves the outcomes in paediatric spinal surgery. Cite this article: Bone Joint J 2018;100-B:493–8

Aims. There is little information about the optimum number of implants to be used in the surgical treatment of idiopathic scoliosis. Retrospective analysis of prospectively collected data from the Swedish spine register was undertaken to discover whether more implants per operated vertebra (implant density) leads to a better outcome in the treatment of idiopathic scoliosis. The hypothesis was that implant density is not associated with patient-reported outcomes, the correction of the curve or the rate of reoperation. Patients and Methods. A total of 328 patients with idiopathic scoliosis, aged between ten and 20 years at the time of surgery, were identified in the Swedish spine register (Swespine) and had patient reported outcomes including the Scoliosis Research Society 22r instrument (SRS-22r) score, EuroQol 5 dimensions quality of life, 3 level (EQ-5D-3L) score and a Viual Analogue Score (VAS) for back pain, at a mean follow-up of 3.1 years and reoperation data at a mean follow-up of 5.5 years. Implant data and the correction of the curve were assessed from radiographs, preoperatively and a mean of 1.9 years postoperatively. The patients were divided into tertiles based on implant density. Data were analyzed with analysis of variance, logistic regression or log-rank test. Some analyses were adjusted for gender, age at the time of surgery, the flexibility of the major curve and follow-up. Results. The mean number of implants per operated vertebra in the low, medium and high-density groups were 1.36 (1.00 to 1.54), 1.65 (1.55 to 1.75) and 1.91 (1.77 to 2.00), respectively. There were no statistically significant differences in the correction of the curve, the SRS-22r total score, EQ-5D-3L index or number of reoperations between the groups (all p > 0.34). In the SRS-22r domains, self-image was marginally higher in the medium implant density group (p = 0.029) and satisfaction marginally higher in the high implant density group (p = 0.034). Conclusion. These findings suggest that there is no clear advantage in using a high number of implants per operated vertebra in the surgical treatment of patients with idiopathic scoliosis. Cite this article: Bone Joint J 2018;100-B:1080–6

We conducted a prospective follow-up MRI study of originally asymptomatic healthy subjects to clarify the development of Modic changes in the cervical spine over a ten-year period and to identify related factors. Previously, 497 asymptomatic healthy volunteers with no history of cervical trauma or surgery underwent MRI. Of these, 223 underwent a second MRI at a mean follow-up of 11.6 years (10 to 12.7). These 223 subjects comprised 133 men and 100 women with a mean age at second MRI of 50.5 years (23 to 83). Modic changes were classified as not present and types 1 to 3. Changes in Modic types over time and relationships between Modic changes and progression of degeneration of the disc or clinical symptoms were evaluated. A total of 31 subjects (13.9%) showed Modic changes at follow-up: type 1 in nine, type 2 in 18, type 3 in two, and types 1 and 2 in two. Modic changes at follow-up were significantly associated with numbness or pain in the arm, but not with neck pain or shoulder stiffness. Age (≥ 40 years), gender (male), and pre-existing disc degeneration were significantly associated with newly developed Modic changes. In the cervical spine over a ten-year period, type 2 Modic changes developed most frequently. Newly developed Modic changes were significantly associated with age, gender, and pre-existing disc degeneration

No previous studies have examined the physical characteristics of patients with cauda equina syndrome (CES). We compared the anthropometric features of patients who developed CES after a disc prolapse with those who did not but who had symptoms that required elective surgery. We recorded the age, gender, height, weight and body mass index (BMI) of 92 consecutive patients who underwent elective lumbar discectomy and 40 consecutive patients who underwent discectomy for CES. On univariate analysis, the mean BMI of the elective discectomy cohort (26.5 kg/m. 2. (16.6 to 41.7) was very similar to that of the age-matched national mean (27.6 kg/m. 2. , p = 1.0). However, the mean BMI of the CES cohort (31.1 kg/m. 2. (21.0 to 54.9)) was significantly higher than both that of the elective group (p < 0.001) and the age-matched national mean (p < 0.001). A similar pattern was seen with the weight of the groups. Multivariate logistic regression analysis was performed, adjusted for age, gender, height, weight and BMI. Increasing BMI and weight were strongly associated with an increased risk of CES (odds ratio (OR) 1.17, p < 0.001; and OR 1.06, p <  0.001, respectively). However, increasing height was linked with a reduced risk of CES (OR 0.9, p < 0.01). The odds of developing CES were 3.7 times higher (95% confidence interval (CI) 1.2 to 7.8, p = 0.016) in the overweight and obese (as defined by the World Health Organization: BMI ≥ 25 kg/m. 2. ) than in those of ideal weight. Those with very large discs (obstructing > 75% of the spinal canal) had a larger BMI than those with small discs (obstructing < 25% of the canal; p < 0.01). We therefore conclude that increasing BMI is associated with CES

This study evaluates factors related to myelopathic symptoms in patients with ossification of the posterior longitudinal ligament (OPLL). A total of 87 patients with OPLL were included. Of these, 53 (Group I) had no symptoms or presented with neck pain and radiculopathy and 34 (Group II) had myelopathic symptoms. Gender, age, and history of trauma were evaluated in the two groups. The range of movement of the cervical spine was measured using plain radiographs. The number of involved segments, type of OPLL, and maximal compression ratio were analysed using CT and signal change in the spinal cord was evaluated using MRI. The patients’ age was found to be significant (p = 0.001). No difference was found between gender and the range of movement in the two groups. The maximum compression of the spinal canal showed a difference (p = 0.03). The signal change of the spinal cord was different between the two groups. In patients with OPLL of the cervical spine, myelopathic symptoms are not related to the range of movement or the number of involved segments.

Study design. A prospective study on predictive factors for the outcome of 164 patients with adult isthmic spondylolisthesis operated on with fusion between 1990 and 2003. Purpose. In view of the need to better select patients for fusion we investigated the use of the pain drawing (PD) and other potential factors for predicting the outcome of fusion. Background. Results on predictive factors of outcome after spinal fusion have been contradictory and large, well defined, patient samples with adequate observation times are lacking. Methods. QuestionnairesF including possible predictive factors as well as PDs were obtained preoperatively. Degree and level of slip were documented. Outcome was quantified by measurement of pain (VAS), Disability Rating Index (DRI), the Oswestry Disability Index and global assessment by the patient into “much better”, “better”, “unchanged” or “worse”. The 2-year follow up rate was 160/164 (98%). Results. In the total sample 49% of patients were much better, 25% better, 14% unchanged and 12% worse. Most factors investigated did not correlate with the outcome including; degree of slip, level of slip, fusion technique, age, smoking, drinking habits, weight, BMI, sciatica, laminectomy, marital status, level of education, type of domicile, possible immigrant status, dominant hand, births and number of children. The following preoperative factors correlated to a worse outcome in the univariate analysis: Not working, no regular exercise, female gender, shortness in stature and a non-organic PD. The multivariate regression analysis showed that work status was the main determinant of outcome. Gender and exercise had less but significant impact (p=0.004 and 0.02, respectively), whereas the PD was of borderline significance (p=0.06). These factors, however, explained only 22% of the variability of outcome. Conclusion. Prediction of outcome after fusion is difficult. Only a limited number of predictive factors were identified, with working preoperatively being the strongest predictor. Also male gender and regular exercise are indicators of a better outcome. Female patients not working, not exercising, or with a non-organic pain drawing, should be informed about their suboptimal chances of an excellent outcome after fusion

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work

Aims. The aims of this study were to evaluate the clinical and radiological outcomes of instrumented posterolateral fusion (PLF) performed in patients with rheumatoid arthritis (RA). . Methods. A total of 40 patients with RA and 134 patients without RA underwent instrumented PLF for spinal stenosis between January 2003 and December 2011. The two groups were matched for age, gender, bone mineral density, the history of smoking and diabetes, and number of fusion segments. . The clinical outcomes measures included the visual analogue scale (VAS) and the Korean Oswestry Disability Index (KODI), scored before surgery, one year and two years after surgery. Radiological outcomes were evaluated for problems of fixation, nonunion, and adjacent segment disease (ASD). The mean follow-up was 36.4 months in the RA group and 39.1 months in the non-RA group. Results. Both groups had significant improvement in symptoms one year after surgery, while the RA group showed some deterioration of outcome scores owing to complications during the second year after surgery. Complications occurred at a higher rate in the group with RA (19 patients, 47.5%) than in those without RA (23 patients, 17.1%) (p < 0.001). A total of 15 patients in the RA group (37.5%) required revision surgery, mainly for implant failure and post-operative infection. . Discussion. Multimodal approaches should be considered when performing instrumented PLF in patients with RA to reduce the rate of complications, such as problems of fixation, post-operative infection and nonunion. Take home message: Specific strategies should be undertaken in order to optimise outcomes in patients with rheumatoid arthritis. Cite this article: Bone Joint J 2016;98-B:102–8

Purpose and background. Identifying features in nonspecific low back pain (NSLBP) subjects that distinguish them from controls, or for elucidating subgroups, has proved elusive. Yet these would be helpful to monitor progress, improve management, and understand the nature of the condition. Previous work using quantitative videofluoroscopy (QF) has indicated that the distribution of motion between lumbar intervertebral joints is more uneven in those with a history of NSLBP. However, there maybe other features of these complex motion patterns yet to be revealed. A multivariate analysis was therefore carried out to explore other possible differences. Methods and results. Intervertebral motion data of L2/3 to L4/5, from a previously published study was used. This examined 40 patients with NSLBP and 40 healthy controls, matched for gender, age and body mass index, who underwent passive recumbent QF in the coronal and sagittal planes. For each motion direction, principal components analysis was carried out and salient dimensions selected. Using a lower dimensional principal components (PC) representation, groups were compared using Hoteling's T test. Linear and quadratic discriminant analysis (LDA and QDA) was carried out using PC representations to examine group differences. The features most clearly distinguishing groups from the LDA was examined graphically. An analysis of the sensitivity of the results to the number of PC dimensions was carried out. The performance of the LDA and QDA classifiers were examined using leave-one-out cross-validation. Conclusions. Hotelling tests revealed significant differences between groups for right and left side-bending. This was confirmed by LDA and QDA. There was no clear difference in the performance of these classifiers and performance did not improve by including more than 4 PC dimensions. Visualisation of the LDA indicated that patients had relatively lower amplitude motion at L4/5, compensated by higher amplitude at L2/3/4. These results point to additional features of lumbar motion that differentiates NSLBP. No conflicts of interest. No funding obtained (however, the original study was funded by NIHR - CATCDRF09)

This study examined spinal fractures in patients admitted to a Major Trauma Centre via two independent pathways, a major trauma (MT) pathway and a standard unscheduled non-major trauma (NMT) pathway. A total of 134 patients were admitted with a spinal fracture over a period of two years; 50% of patients were MT and the remainder NMT. MT patients were predominantly male, had a mean age of 48.8 years (13 to 95), commonly underwent surgery (62.7%), characteristically had fractures in the cervico-thoracic and thoracic regions and 50% had fractures of more than one vertebrae, which were radiologically unstable in 70%. By contrast, NMT patients showed an equal gender distribution, were older (mean 58.1 years; 12 to 94), required fewer operations (56.7%), characteristically had fractures in the lumbar region and had fewer multiple and unstable fractures. This level of complexity was reflected in the length of stay in hospital; MT patients receiving surgery were in hospital for a mean of three to four days longer than NMT patients. These results show that MT patients differ from their NMT counterparts and have an increasing complexity of spinal injury. Cite this article: Bone Joint J 2015;97-B:235–9