Predictive factors for critical care dependency after posterior spinal fusion for adolescent idiopathic scoliosis.

Aims: Historically, patients undergoing surgery for adolescent idiopathic scoliosis (AIS) have been nursed postoperatively in a critical care (CC) setting because of the challenges posed by prone positioning, extensive exposures, prolonged operating times, significant blood loss, major intraoperative fluid shifts, cardiopulmonary complications, and difficulty in postoperative pain management. The primary aim of this paper was to determine whether a scoring system, which uses Cobb angle, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and number of levels to be fused, is a valid method of predicting the need for postoperative critical care in AIS patients who are to undergo scoliosis correction with posterior spinal fusion (PSF). Methods: We retrospectively reviewed all AIS patients who had undergone PSF between January 2018 and January 2020 in a specialist tertiary spinal referral centre. All patients were assessed preoperatively in an anaesthetic clinic. Postoperative care was defined as ward-based (WB) or critical care (CC), based on the preoperative FEV1, FVC, major curve Cobb angle, and the planned number of instrumented levels. Results: Overall, 105 patients were enrolled. Their mean age was 15.5 years (11 to 25) with a mean weight of 55 kg (35 to 103). The mean Cobb angle was 68° (38° to 122°). Of these, 38 patients were preoperatively scored to receive postoperative CC. However, only 19% of the cohort (20/105) actually needed CC-level support. Based on these figures, and an average paediatric intensive care unit stay of one day before stepdown to ward-based care, the potential cost-saving on the first postoperative night for this cohort was over £20,000. There was no statistically significant difference between the Total Pathway Score (TPS), the numerical representation of the four factors being assessed, and the actual level of care received (p = 0.052) or the American Society of Anesthesiologists grade (p = 0.187). Binary logistic regression analysis of the TPS variables showed that the preoperative Cobb angle was the only variable which significantly predicted the need for critical care. Conclusion: Most patients undergoing posterior fusion surgery for AIS do not need critical care. Of the readily available preoperative measures, the Cobb angle is the only predictor of the need for higher levels of care, and has a threshold value of 74.5°.

Surgical complications in neuromuscular scoliosis surgery: systematic review and meta-analysis of the last ten years.

PURPOSE: Surgical correction of neuromuscular scoliosis is often a challenging and extensive procedure. Due to this complexity and the high disease burden that these patients carry, per and post-operative complications are not uncommon. The purpose of this study was to systematically review and describe the pooled rates of postoperative complications and analyze risk factors for complications in neuromuscular scoliosis surgery described in the literature in the last ten years. METHODS: A systematic review of the English literature across multiple databases was conducted using search criteria (neuromuscular scoliosis AND complications) and using PRISMA guidelines (Jan 2012-July 2022). Studies with less than 30 patients and follow-up of < 2 years were excluded. Data extraction and meta-analysis were performed using random mode effect. Statistical analysis was conducted using OpenMeta software. Meta-regression analysis was used to detect risk factors (surgical approach, intraoperative time, intraoperative blood loss, preoperative Cobb angle and patient diagnosis) associated with each complication group. Confidence interval (CI) was set at 95%. RESULTS: Twenty-two studies met the inclusion criteria involving 2155 patients. The level of evidence among studies were III (9) and IV (13). The most common primary diagnosis was cerebral palsy (43%) followed by Duchenne muscle dystrophy (20%), myelomeningocele (7.4%), spinal muscle atrophy (7.1%), Rett syndrome (< 2%) and combined other pathologies (20.2%). The pooled incidence rate of wound complications was the highest, amongst all complications, at 13.3% (CI 10.838 to 16.861); closely followed by respiratory complications (11.8%;CI 5.7 to 19.7). Implant failure occurred in 7.1% cases (CI 6.418 to 11.465), gastrointestinal complications was 5.2%; CI 2.4 to 8), pseudarthrosis in (4.6%;CI 2.2 to 6.9) and neurological deficit in 2.9% (CI 1.989 to 6.086). The pooled rate of revision surgery was (9.6%; CI 6.2 to 12.9). Heterogeneity was assessed using I2 test which results were moderately heterogeneous. Meta-regression analysis revealed that the diagnosis of myelomeningocele or Duchenne muscle dystrophy or spinal muscle atrophy were strongly associated with wound and respiratory complications (p = 0.007 and p = 0.005, respectively). CONCLUSION: Wound-related (13.3%) and respiratory complications (11.8%) remain the most common complications among studies after corrective surgery for neuromuscular scoliosis. Both are significantly associated with Duchenne muscle dystrophy, spinal muscle atrophy and myelomeningocele.

Hip reduction surgery versus scoliosis correction in non-ambulant neuromuscular patients: which surgery is the first step?

PURPOSE: Children and young adults with neuromuscular disorders have a high incidence of both spine and hip deformities. The aim of this study was to evaluate the outcome of either primary scoliosis or hip surgery in children and young adults with neuromuscular disorders. METHODS: A retrospective study was conducted on all children and young adults with neuromuscular-related synchronous hip subluxation/dislocation and scoliosis undergoing hip or scoliosis surgery in our institution between 2012 and 2021 with a minimum follow-up of 24 months. Demographic and operative data were collected; radiological parameters were measured preoperatively and postoperatively at final follow-up. RESULTS: Forty neuromuscular patients with synchronous hip displacement and scoliosis were included. Twenty patients with an average age of10.2 years had hip correction surgery performed primarily, with a mean follow-up of 54.9 (24-96) months. The other 20 patients with an average age of 12.4 years had scoliosis correction first, with a mean follow-up of 40 (24-60) months. In the "Hip first" group, pelvic obliquity, hip MP and Cobb angle were 16.8°, 71%, and 49°, respectively. At final follow-up, the mean pelvic obliquity and Cobb angles significantly progressed to 27.2° (p = 0.003) and 82.2° (p = 0.001), respectively. Eighteen patients (90%) required scoliosis correction after the hip surgery. In the "Scoliosis first" group, the mean pelvic obliquity, hip MP and Cobb angle were 21.2°, 49% and 65.5°, respectively. At final follow-up, both pelvic obliquity and Cobb angle significantly improved to 8.44° (p = 0.002) and 23.4° (p = 0.001), respectively. In 11/20 (55%) patients, the hip MP had significantly increased following the spinal surgery to 62% (p = 0.001), but only 5/20 (25%) patients underwent hip surgery after scoliosis correction. CONCLUSION: In neuromuscular patients presenting with synchronous hip displacement and scoliosis deformity, corrective scoliosis surgery is associated with a significant correction of pelvic obliquity and lower rates of secondary hip surgery. On the other hand, primary hip surgery does not reduce the risk of pelvic obliquity and scoliosis deformity progression.

Restoration of the sagittal profile according to the Roussouly classification reduces mechanical complications and revision surgery in older patients undergoing surgery for adult spinal deformity (ASD).

PURPOSE: The mechanical complications related to ASD remain a concern due to their morbidity and associated revision surgery. Restoration of each patient's Roussouly profile may reduce these. Our aim was to examine if the restoration of the Roussouly profile reduced these complications and revision rates in older patients operated for degenerative ASD. METHODS: Retrospective analysis of a single-centre, 2-year minimum follow-up patient database. All patients undergoing corrective surgery (≥ 4 levels) for ASD were included with analysis of demographic data, operative records, restoration of Roussouly sagittal profile, mechanical complications and revision rates. Univariate and multivariate analysis was conducted. RESULTS: Fifty-two patients were included (mean age was 72.3 years, average follow-up 56.3 months). Twenty-six patients had a "restored" profile (50%) and 26 an "unrestored" profile (50%). The incidence of mechanical complications was 7 (27%) and 23 (88%) for the restored and unrestored groups, respectively (p < 0.001). Revision rates were 4 (15.4%) and 18 (69.2%), respectively (p < 0.000), in the restored and unrestored profiles. Univariate analysis determined that profile restoration and BMI were associated with mechanical complications and revision surgery, whilst only the profile restoration status maintained its statistical power in multivariate analysis (p = 0.002 and p = 0.002, respectively). Age was not a significant factor in univariate analysis. The relative risk for mechanical failure and revision surgery was 5.6 times (CI 1.929-16.39) and 3.08 times (CI 1.642-5.734) greater if the profile was not restored. CONCLUSIONS: Achieving each patient's ideal Roussouly profile is associated with a reduced incidence of mechanical complications and revision rates in the older population after surgery for degenerative ASD.

A Pilot Study to Establish the Leadership Development Needs of Community Pharmacist Leads in Lambeth, South East London.

Primary care networks (PCNs) are geographical networks consisting of 30,000 to 50,000 patients and groups of general practices working in a multidisciplinary team, including community pharmacists. Community pharmacy (CP) neighbourhood leads act as a conduit between pharmacy contractors and general practitioners (GPs) in these networks, sharing information and providing a voice for the community pharmacy locally. The Lambeth medicines team (NHS South East London Integrated Care Board) recognised the need to continue funding these leadership roles to address barriers to relationship-building between community pharmacies and general practices, the consistency of service delivery and effective communication. The aim of this study was to understand the current experience of CP neighbourhood leads to inform their further development. All eight CP neighbourhood leads individually completed a semi-structured interview over Microsoft Teams, which was then reviewed using content analysis. Ethical approval was received. Leads reported the use of common communication methods such as emails, text messaging applications and telephone calls to engage GPs and pharmacies in their neighbourhoods. Barriers to undertaking their roles included time constraints, delays in responses, high workloads and competing pressures. Other factors impacting their effectiveness and ability to undertake their roles included the scheduling of meetings outside of working hours, finding time during busy working days and organising locum cover on an ad hoc basis. The leads also reported they spent more time focussed on building relationships with their peers and less time focussed on general practice colleagues. Support for CP neighbourhood leads could include ensuring that funded time is protected; communication and technology training; and the provision of more structural support for communication with GPs. The findings of this study can be used to inform future work.

Vertebral body tethering in adolescent idiopathic scoliosis with more than 2 years of follow-up- systematic review and meta-analysis.

BACKGROUND CONTEXT: Whilst spinal fusion remains the gold standard in the treatment of adolescent idiopathic scoliosis (AIS), anterior vertebral body tethering (AVBT) is gaining momentum with relatively few studies on its efficacy thus far. PURPOSE: To conduct a systematic review reporting on the early results of AVBT for patients undergoing surgery for AIS. We aimed to systematically evaluate the relevant literature pertaining to the efficacy of AVBT with respect to degree of correction of the major curve Cobb angle, complications and revision rates. STUDY DESIGN/SETTING: Systematic review. PATIENT SAMPLE: Of a total of 259 articles, 9 studies met the inclusion criteria and were analysed. Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months. OUTCOME MEASURES: Degree of Cobb angle correction, complications and revision rates were used as outcome measures. METHODS: A systematic review of the literature on AVBT was performed for studies published between Jan 1999-March 2021 applying the PRISMA guidelines. Isolated case reports were excluded. RESULTS: Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months. There was a significant correction of the main thoracic curve of scoliosis (mean preoperative Cobb angle 48.5°, post-operative Cobb angle at final follow-up of 20.1°, P = 0.01). Overcorrection and mechanical complications were seen in 14.3% and 27.5% of cases, respectively. Pulmonary complications including atelectasis and pleural effusion were seen in 9.7% of patients. Tether revision was performed in 7.85%, and revision to a spinal fusion in 7.88%. CONCLUSION: This systematic review incorporated 9 studies of AVBT and 196 patients with AIS. The complication and revision to spinal fusion rates were 27.5% and 7.88%, respectively. The current literature on AVBT is restricted largely to retrospective studies with non-randomised data. We would recommend a prospective, multi-centre trial of AVBT with strict inclusion criteria and standardised outcome measures.

Single-wavelength polarization- and mode-division multiplexing free-space optical communication at 689 Gbit/s in strong turbulent channels.

We experimentally demonstrated, for, it is believed, the first time, high-capacity polarization- and mode-division multiplexing free-space optical transmission with adequate strong turbulence resiliency. A compact spatial light modulator-based polarization multiplexing multi-plane light conversion module was employed to emulate strong turbulent links. By employing advanced successive interference cancellation multiple-input multiple-output decoder and redundant receive channels, the strong turbulence resiliency was significantly improved in a mode-division multiplexing system. As a result, we achieved a record-high line rate of 689.2 Gbit/s, channel number of 10, and net spectral efficiency of 13.9 bit/(s Hz) in a single-wavelength mode-division multiplexing system with strong turbulence.

Engineering of clarithromycin loaded stimulus responsive dissolving microneedle patches for the treatment of biofilms.

This study aimed to fabricate clarithromycin laden Eudragit S-100-based microfibers (MF), microfibers coated film (MB), clarithromycin loaded polyvinyl pyrollidone, hyaluronic acid and sorbitol-based dissolving microneedle patches (CP) and microfibers coated microneedle patches (MP). Morphological and phase analysis of formulations were carried out by scanning electron microscopy and differential scanning calorimetry, X-ray diffraction, respectively. Substrate liquefaction test, in vitro drug release, antimicrobial assay and in vivo antibiofilm studies were performed. MF exhibited a uniform surface and interconnected network. Morphological analysis of CP revealed sharp-tipped and uniform-surfaced microstructures. Clarithromycin was incorporated within MF and CP as amorphous solid. Liquefaction test indicated hyaluronate lyase enzyme responsiveness of hyaluronic acid. Fibers-based formulations (MF, MB and MP) provided an alkaline pH (7.4) responsive drug release; ∼79 %, ∼78 % and ∼81 %, respectively within 2 h. CP showed a drug release of ∼82 % within 2 h. MP showed ∼13 % larger inhibitory zone against Staphylococcus aureus (S. aureus) as compared to MB and CP. A relatively rapid eradication of S. aureus in infected wounds and subsequent skin regeneration was observed following MP application as compared to MB and CP indicating its usefulness for the management of microbial biofilms.

Single-wavelength transmission at 1.1-Tbit/s net data rate over a multi-modal free-space optical link using commercial devices.

We employ commercial mode-selective photonic lanterns to implement mode multiplexing and demultiplexing for high-capacity free-space optical communications. Moreover, we design a time-division-multiplexed frame structure to efficiently emulate multiple independent transmitters with channelized precoding using only one transmitter. To maximize the throughput of the system, we optimize the modes selected for carrying data, and apply adaptive loading to different channels. By leveraging mode- and polarization-division multiplexing, the free-space optical data link comprising multiple independent channels provides an aggregate net data rate of 1.1 Tbit/s and net spectral efficiency of 28.35 bit/s/Hz. Different from many previous demonstrations based on delayed or partially delayed copies of identical data streams, to the best of our knowledge, ours is a record-high net data rate and net spectral efficiency achieved by a single-wavelength mode-division multiplexed free-space optical communication system with fully independent channels. Moreover, all key devices used in this work, including optical transponder, multiplexer, and demultiplexer are commercially available.

Reconstruction of irreparable rotator cuff tears with an acellular dermal matrix in elderly patients without joint arthritis.

Background: Reverse shoulder arthroplasty is the mainstay of treatment for symptomatic irreparable rotator cuff tears in elderly patients without arthritis. However, this treatment incurs significant costs and is a major surgical undertaking. This study explores an alternative that involves the reconstruction of irreparable rotator cuff tears using an acellular dermal matrix in elderly patients without established joint arthritis. Methods: We prospectively evaluated the reconstruction of massive irreparable rotator cuff tears in 21 patients aged 68 years and over without radiographic glenohumeral joint osteoarthritis in whom conservative management had failed. A human dermal acellular matrix graft was used as a bridging graft for reconstruction. Pain scores, Oxford Shoulder Scores and ranges of movement were all assessed preoperatively and postoperatively. The mean follow-up period was 5.8 years (range 2.6 to 8.9 years). Results: Statistically significant (p < 0.05) improvements were observed in Oxford Shoulder Scores (mean preoperative score, 21; mean postoperative score, 46), pain scores (mean preoperative score, 6; mean postoperative score, 0) and ranges of movement. Patients also reported a high satisfaction rate with the procedure. Discussion: Human tissue matrix allografts could serve as a suitable option for the treatment of elderly patients with massive irreparable rotator cuff tears without arthritis.

Demonstration of 10-channel mode- and polarization-division multiplexed free-space optical transmission with successive interference cancellation DSP.

We experimentally demonstrate 10-channel mode-division multiplexed free-space optical transmission with five spatial modes, each carrying 19.6925-Gbaud dual-polarization quadrature phase shift keying signals. Strong inter-mode cross talk is observed in our commercially available photonic lantern based system when using a complete orthogonal mode set as independent channels. A successive interference cancellation based multiple-input multiple-output digital signal processing (DSP) algorithm is first applied to mitigate the inter-mode cross talk in mode-division multiplexed systems. The DSP also supports unequal transmit and receive channel numbers to further improve the cross talk resiliency. Compared to the conventional minimum mean square error DSP, the required optical signal-to-noise ratio of the successive interference cancellation DSP is decreased by approximately 5 dB at the hard-decision forward error correction limit. As a result, this system demonstrates a record-high independent channel number of 10 and spectral efficiency of 13.7 b/s/Hz in mode-division multiplexed free-space optical systems.

Recent applications of electrical, centrifugal, and pressurised emerging technologies for fibrous structure engineering in drug delivery, regenerative medicine and theranostics.

Advancements in technology and material development in recent years has led to significant breakthroughs in the remit of fiber engineering. Conventional methods such as wet spinning, melt spinning, phase separation and template synthesis have been reported to develop fibrous structures for an array of applications. However, these methods have limitations with respect to processing conditions (e.g. high processing temperatures, shear stresses) and production (e.g. non-continuous fibers). The materials that can be processed using these methods are also limited, deterring their use in practical applications. Producing fibrous structures on a nanometer scale, in sync with the advancements in nanotechnology is another challenge met by these conventional methods. In this review we aim to present a brief overview of conventional methods of fiber fabrication and focus on the emerging fiber engineering techniques namely electrospinning, centrifugal spinning and pressurised gyration. This review will discuss the fundamental principles and factors governing each fabrication method and converge on the applications of the resulting spun fibers; specifically, in the drug delivery remit and in regenerative medicine.

Enhanced recovery after surgery (ERAS) in adolescent idiopathic scoliosis (AIS): a meta-analysis and systematic review.

STUDY DESIGN: A systematic review reporting on the efficacy of an ERAS protocol in patients undergoing spinal fusion for AIS. OBJECTIVE: To systematically evaluate the relevant literature pertaining to the efficacy of ERAS protocols with respect to the length of stay, complication, and readmission rates in patients undergoing posterior spinal corrective surgery for AIS. ERAS is a multidisciplinary approach aimed at improving outcomes of surgery by a specific evidence-based protocol. The rationale of this rapid recovery regimen is to maintain homeostasis so as to reduce the postoperative stress response and pain. No thorough review of available information for its use in AIS has been published. METHODS: A systematic review of the English language literature was undertaken using search criteria (postoperative recovery AND adolescent idiopathic scoliosis) using the PRISMA guidelines (Jan 1999-May 2020). Isolated case reports and case series with < 5 patients were excluded. Length of stay (LOS), complication and readmission rates were used as outcome measures. Statistical analysis was done using the random effects model. RESULTS: Of a total of 24 articles, 10 studies met the inclusion criteria (9 were Level III and 1 of level IV evidence) and were analyzed. Overall, 1040 patients underwent an ERAS-type protocol following posterior correction of scoliosis and were compared to 959 patients following traditional protocols. There was a significant reduction in the length of stay in patients undergoing ERAS when compared to traditional protocols (p < 0.00001). There was no significant difference in the complication (p = 0.19) or readmission rates (p = 0.30). Each protocol employed a multidisciplinary approach focusing on optimal pain management, nursing care, and physiotherapy. CONCLUSION: This systematic review demonstrates advantages with ERAS protocols by significantly reducing the length of stay without increasing the complications or readmission rates as compared to conventional protocols. However, current literature on ERAS in AIS is restricted largely to retrospective studies with non-randomized data, and initial cohort studies lacking formal control groups. LEVEL OF EVIDENCE: 3.

Ability of Spine Specialists to Identify Psychosocial Risk Factors as Obstacles to Recovery in Patients with Low Back Pain-Related Disorders.

STUDY DESIGN: Prospective study. PURPOSE: Yellow flags are psychosocial associated with a greater likelihood of progression to persistent pain and disability. These are referred to as obstacles to recovery. Despite their recognized importance, it is unknown how effective clinicians are in detecting them. The primary objective of this study was thus to determine the effectiveness of spine specialist clinicians in detecting the presence of yellow flags in patients presenting to an orthopedic outpatient clinic with low back-related disorders. OVERVIEW OF LITERATURE: Psychosocial factors have been previously studied as important predictors of prognosis in patients with low back pain. However, the ability of spinal specialist to identify them remains unknown. METHODS: A prospective, single-center, consecutive cohort study was conducted over a period of 30 months. All new patients with low back-related disorders regardless of pathology completed a Yellow Flag Questionnaire that was adapted from the psychosocial flags framework. Clinicians assessing these patients completed a standardized form to determine which and how many yellow flags they had identified during the consultation. RESULTS: A total of 130 patients were included in the analysis, and the clinicians reported an average of 5 flags (range, 0-9). Fear of movement or injury was the most frequently reported yellow flag, reported by 87.7% (n=114) of patients. Clinician sensitivity in detecting yellow flags was poor, correctly identifying only 2 flags, on average, of the 5 reported by patients, with an overall sensitivity of only 39%. CONCLUSIONS: The ability of spine specialists to identify yellow flags is poor and can be improved by asking patients to complete a simple screening questionnaire.

Venous thromboembolic events in hand surgery.

The risks of venous thromboembolism (VTE) following total hip and knee arthroplasty have been widely published. Our aim was to investigate the recorded incidence of VTE events at the time of elective and trauma hand surgery. The UK National Hospital Episode Statistics (HES) data linking VTE events with hand surgery for the financial years 2010-2012 were analysed. The local VTE rates following hand surgical procedures were also analysed. Finally, a cost assessment of VTE thromboprophylaxis was performed according to the British Society for Surgery of the Hand (BSSH) guidelines. 334,211 hand surgical procedures were performed throughout England of which there were 13 DVT and 27 PE events. These events were seen in patients with pre-existing comorbidities. The annual incidence of VTE is 0.006% at most in hand surgical patients in England. The cost of implementing mechanical VTE thromboprophylaxis to all patients having hand surgery would amount to £6,336,641 over 2 years. The cost of treatment for all VTE events would amount to £20,418. VTE prophylaxis is probably not necessary in patients undergoing isolated elective or trauma hand surgical procedures.

Coronavirus Disease 2019 Transmission: Blood Viremia and Aerosol Generation from Spinal Surgery. Is There an Increased Risk to the Surgical Team?

As a respiratory pathogen, the novel coronavirus is commonly associated with aerosol-generating procedures. However, it is currently unclear whether spinal surgical procedures pose an additional risk of viral transmission to the surgical team. We reviewed the available evidence to ascertain the presence of coronavirus disease 2019 (COVID-19) blood viremia and the virus' blood transmissibility, as well as evidence of blood-aerosol generation and operating room contamination from spinal surgical procedures. There is established evidence of COVID-19 blood viremia, a viral pathogenic cycle via angiotensin-converting enzyme 2 (ACE-2) receptors and similar blood transmission risk data from the SARS (severe acute respiratory syndrome)/MERS (Middle East respiratory syndrome) era. Spinal surgical practices demonstrate significant blood-aerosol generation from the operative wound due to the use of common surgical instruments, such as electrocautery, as well as high-speed and high-impact devices. Based on the evidence, there is an established additional risk of viral transmission faced by surgical teams from blood-aerosols generated from the operative wound of COVID-19- infected patients via the inhalation of virus-laden aerosols and the subsequent initiation of the viral pathogenic cycle through binding with pulmonary ACE-2 receptors. Recognizing this additional risk amidst the ongoing pandemic serves as a caution to front-line surgical personnel to strictly adhere to personal protective equipment usage in operating rooms, to modify surgical techniques to reduce the hazard of surgical aerosol generation and COVID-19 viral exposure, and to consider it as an integral aspect of planning and adapting to the "new normal" operating practices.

Dural tears in primary decompressive lumbar surgery. Is primary repair necessary for a good outcome?

STUDY DESIGN: Case control series with prospective data collection. OBJECTIVE: To establish whether incidental durotomy treated without primary suture repair adversely affects the outcome following lumbar surgery in the longer term. METHOD: Outcome scores from a prospective database were used for an audit of dural tears in primary lumbar decompressive surgery. Outcome data collected includes the Short Form 36 General Health Questionnaire (SF36), the Oswestry Disability Index (ODI) and Visual Analogue Scores for leg pain (VAL) and back pain (VAB). RESULTS: Out of 200 consecutive procedures, a dural tear occurred in 19 (9.5%) patients. Of 19 patients with a dural tear, data was incomplete in 4 patients, and 1 further patient who had their dural tear sutured was excluded, leaving 14 patients to be studied. There were seven males and seven females, with an average age of 50.8 years (31-69). These 14 patients (group 1) were compared to a matched group (age, sex, surgical diagnosis and duration of follow-up) of 14 patients (group 2) with no tear. Both groups had similar pre-operative scores. At 6-month follow-up, both groups had significant improvements in all outcomes measures except for the general health domain of the SF-36. At final follow-up, patients with dural tears appeared to have better improvements in outcome measures amongst the VAB, VAL and ODI with similar scores in the SF-36 domains. CONCLUSION: Our study demonstrates that incidental durotomy in primary lumbar decompressive surgery can be successfully managed without primary suture repair with no adverse effect on surgical outcome in the longer term.

Dose response and structural injury in the disability of spinal injury.

INTRODUCTION: In traumatic injury there is a clear relationship between the dose of energy involved, structural tissue damage and resultant disability after recovery. This relationship is often absent in cases of non-specific chronic low back pain that is perceived by patients as attributed to a workplace injury. There are many studies assessing risk factors for non-specific low back pain. However, studies addressing causality of back pain are deficient. PURPOSE: To establish whether there exists a causal relationship between structural injury, low back pain and spinal disability. METHODS: Retrospective analysis of prospectively gathered validated spinal outcome measures [Oswestry disability index (ODI), low back outcome score (LBO), modified somatic perception (MSP), modified Zung depression index (MZD)] between patients with healed high energy thoracolumbar spinal fractures and patients with self-perceived work-related low back pain. Causality was established according to two of Bradford Hill's criteria of medical causality, temporal and dose-response relationships. RESULTS: Twenty-three patients with spinal fractures (group 1) of average age 44 years were compared to 19 patients with self-reported back pain in the workplace pursuing claims for compensation (group 2) of average age 48 years. Both groups were comparable in terms of age and sex. The average ODI in group 1 was 28 % (SD 19) compared to 42 % (SD 19) in group 2 (P < 0.05). Similarly, LBOS was 39.7 versus 24.3 (P < 0.05), MSP 4.3 versus 9.3 (P < 0.05) and MZD 20.2 versus 34.8 (P < 0.05) in groups 1 and 2, respectively. CONCLUSION: Despite high-energy trauma and significant structural damage to the spine, patients with the high energy injuries had better spinal outcome scores in all measures. There is no 'dose-response' relationship between structural injury, low back pain and spinal disability. This is the reverse of what would be anticipated if structural injury was the cause of disability in workplace reported onset of low back pain.