Repetitive manual handling caused 31% of all work related musculoskeletal disorders in 2015, with the back being the site of injury 38% of the time. Despite its high resilience, studies have shown that intervertebral discs can be damaged during repetitive loading at physiological motions, causing cumulative damage and disc herniation. To understand the mechanism of disc injury resulting from repetitive lifting, it is important to measure disc deformations/strains accompanied by MRI imaging to identify disc tissue damage. Therefore, the aim of this study was to examine associations between the magnitude of 3D internal strains, tissue damage and macroscopic evidence of disc injury after simulated repetitive lifting on normal human lumbar discs. Sixteen cadaver lumbar functional spinal units (FSUs) were subjected to pre-test MRI. Eight FSUs (control) underwent 20,000 cycles or until failure (5 mm displacement) of loading under compression (1.7 MPa – to simulate lifting a 20 kg weight) + flexion (13°) + right axial rotation (2°) using a novel Hexapod Robot. The remaining eight FSUs (experimental) had a grid of tantalum wires inserted, and stereoradiographs were taken to track internal disc displacements at increasing cyclic intervals. Maximum shear strains (MSS) were calculated from the displacements using radiostereometric analysis at cycle 1 and 20,000 cycles (or failure). Post-test MRI was conducted to determine the extent of tissue damage and associated with regions of highest MSS. A repeated measures ANOVA was performed on MSS with a within–subjects factor of cycle number (cycle 1 and failure cycle) and a between subjects-factor of disc region and failure type (p < 0 .05). Pfirrmann grading revealed mostly normal discs [I (N=2), II (N=13), and III (N=1)]. No significant difference in MSS between control and experimental groups was found for number of cycles to failure (p=0.279). Pre and post-test MRI analysis revealed that 13 specimens were injured after repetitive lifting with either an endplate failure (N=9) or disc bulge (N=4), and two specimens did not fail. Failure strain was significantly greater than cycle 1 in all regions except posterior, left/right posterolateral (p>0.109). Largest MSS at failure was seen in the anterior (60%), and left/right posterolateral regions (64% and 70%, respectively). MSS at failure for the endplate failure group was significantly larger than the no injury group in all regions except right lateral and nucleus (p>0.707). Disc bulge group MSS was significantly larger than the no injury group in the anterior, right anterolateral, and left/right posterolateral regions (p < 0 .027). Simulated repetitive lifting led to largest shear strains in the anterior, left and right posterolateral regions that corresponded to annular tears or annular protrusion. The no injury group shear strain was less than 50% in all regions, indicating there may be a threshold that could be associated with tissue damage linked with injuries such as disc bulge and endplate failure. There was no evidence of disc herniation in normal discs, agreeing with current clinical knowledge. These results may be indicative of the effects of repetitive manual handling on normal discs of younger patients

Introduction. In degenerative lumbar spine, it seems possible that foraminal stenosis is over-diagnosed as axial scanning is not performed in the plane of the exiting nerve root. We carried out a two-part study to determine the true incidence of foraminal stenosis. Patients and Methods. Initially we performed a retrospective analysis of radiology reports of conventional Magnetic Resonance Imaging in 100 cases of definite spinal stenosis to determine the incidence of reported ‘foraminal stenosis’. Subsiquently we performed a prospective study of MRI including fine slice T2 and T2 STIR coronal sequences in 100 patients with suspected stenosis. Three surgeons and one radiologist independently compared the diagnoses on conventional axial and sagittal sequences with the coronal scans. Results. The retrospective analysis found that ‘foraminal stenosis’ was reported by radiologists in 46% using conventional axial and sagittal sequences. In the prospective study of 100 patients suspected of having stenosis, spinal stenosis was reported in 40; degenerative spondylolisthesis in 14; posterolateral disc herniation in 14; normal report in 13; far lateral disc herniation in 7; isthmic (lytic) spondylolisthesis in 6; and degenerative scoliosis in 6. Conventional sequences diagnosed lateral recess stenosis reliably, but also suggested foraminal stenosis in 43%. However, coronal sequences clearly showed no foraminal nerve compression at all. In degenerative spondylolisthesis conventional scans suggested foraminal stenosis in 10 of 14 cases. Coronal imaging again showed no foraminal stenosis. Excellent correlation was found in normal spines and in disc herniation. Foraminal nerve compression was confirmed by conventional and coronal imaging only in isthmic spondylolisthesis, degenerative scoliosis and far lateral disc herniation. Conclusion. The addition of coronal MRI proves that foraminal stenosis is over-diagnosed. True foraminal stenosis definitely exists in isthmic spondylolisthesis, degenerative scoliosis and far lateral disc herniation, but we question its existence in spinal stenosis and degenerative spondylolisthesis

Cervical total disc replacement has been in practice for years now as a viable alternative to cervical fusion in suitable cases, aspiring to preserve spinal motion and prevent adjacent segment disease. Reports are rife that neck pain emerges as an annoying feature in the early postoperative period. The facet joint appears to be the most likely source of pain. 50 patients were prospectively followed up through 5 years after having received disc replacement surgery, indicated for symptomatic soft disc herniation of the cervical spine presenting with radiculopathy. • All were skeletally mature and aged between 22 to 50. • All had failed a minimum of 6 months conservative therapy. • Up to 2 disc levels were addressed. C3 till C7 levels. • Single surgeon (first author). • NDI > 30% (15/50). • Deteriorating radicular neurology. We excluded those with degenerative trophic changes of the cervical spine, focal instability, trauma, osteoporosis, previous cervical spine surgery, previous infection, ossifying axial skeletal disease and inflammatory spondyloarthritides. The device used was an unconstrained implant with stabilizing teeth. Over the 5 years, we studied their postoperative comfort level via the Neck Disability Index (NDI) and Visual Analogue Score (VAS). Pre-operative and post-operative analysis of the sagittal axis and of involved facet joints were done. 22 patients suffered postoperative neck pain as reflected by the NDI and VAS scores. Of these, 10 reported of neck pain even 24 months after surgery. However, none were neurologically worse and all patients returned to their pre-morbid functions and were relieved of pain by 28 months. All 22 patients reported of rapid dissolution of neckache after peri-facetal injections of steroids were done under image guidance. We draw attention to the facet joint as the pain generator, triggered by inappropriate implant height, eccentric stresses via hybrid constructs, eccentric loading due to unconstrained devices and unaddressed Luschka joint degeneration. Such factors require careful selection of patients for surgery, necessitate proper pre-operative templating and call for appropriate technical solutions during surgery

Silicon nitride spinal fusion cages have been successfully used in the treatment or correction of stenosis, disc herniation, trauma, and other deformities of the spinal column since 2008. To date over 14,000 devices have been implanted with perioperative and postoperative complication rates of less than 0.2%. This remarkable achievement is due in part to the material itself. Silicon nitride is an ideal interbody material, possessing high strength and fracture toughness, inherent phase stability, biocompatibility, hydrophilicity, excellent radiographic imaging, and bacterial resistance. These characteristics can lead to implants that aid in prevention of nosocomial infections and achieve rapid osteointegration. In this paper, we will review the various in vitro and in vivo studies that demonstrate silicon nitride's effective bacteriostatic and osteointegration characteristics, and compare these to the two most common cage materials – titanium and poly-ether-ether-ketone (PEEK). Human case studies will be also reviewed to contrast the clinical performance of these biomaterials. In comparison to the traditional devices, silicon nitride shows lower infection rates, higher bone apposition, and essentially no fibrous tissue growth on or around the implant. To better understand the mechanisms underlying these benefits, surface characterization studies using scanning electron microscopy coupled with XPS chemical analyses, sessile water drop techniques and streaming zeta potential measurements will be reported. Data from these studies will be discussed in relation to the physiochemical reasons for the observed behavior. Silicon nitride is a non-oxide ceramic in its bulk; but possesses a protective Si-N-O transitional layer at its surface. It will be shown that the chemistry and morphology of this layer can be modified in composition, thickness and structure resulting in marked changes in chemical species, surface charge, isoelectric points and wetting behavior. It is postulated that the needle-like grain structure of silicon nitride coupled with its enhanced wettability play important roles in inhibiting biofilm formation, while its surface chemical environment consisting of silicon diimide Si(NH). 2. , silicic acid Si(OH). 4. , and derivatives of ammonia, NH. 3. , NH. 4. OH, lead to improved bone reformation and bacteriostasis, respectively. Few materials have this combination of properties, making silicon nitride a unique biomaterial that provides improved patient care and outcomes with low comorbidities

Background:. The reported prevalence of sciatica ranges from 1.2% to 43%. Epidural injections are the most commonly performed interventions for sciatica. Setting:. A provincial based spinal unit. Objective:. To evaluate the effectiveness of lumbar epidural injections with local anaesthetic and steroids, in patients with sciatica secondary to disc herniation in providing effective pain relief. Methods:. A retrospective chart review of 25 patients given an epidural with local anaesthetic mixed with non-particulate betamethasone. Patient outcomes were measured at baseline and 6 weeks with the Oswestry Disability Index 2.0 (ODI). Observations of gender, sex, co-morbities and medication intake were made. Decrease of 50% in the Oswestry scores were considered significant. Results:. Significant pain relief was seen at 6 weeks in 80% of patients and medication intake was decreased. Limitations:. The study limitations include the lack of a placebo group and the fact that this is a preliminary report of the 25 patients. Conclusion:. Overall, 80% of patients with sciatica benefited from lumbar epidural injections

Purpose of Study. Discecomy is a common operation peformed for back pain at our hospital. We analysed the theatre register looking at demographic and health data for our patients to shed more light on this cases. Description of Methods. Entries in the spinal unit theatre registers from 2000–2012 were reviewed, and all patients undergoing discectomy for disc herniation recorded analysed regarding demographics and epidemiology. Summary Of Results. A total of 171 patients had operations in our theatres. Of these patients the large majority were females. The age distribution was 45 to 50 years. The lumbar spine was the commonest region operated, especially the lower lumbar spine. We had very low repeat operations from failed surgery or requiring herniation. Conclusion. Surgical registers are an important tool in understanding pathology in the communities we serve. We can track the type of patients treated and then plan appropriate intervention programmes. It also helps to follow-up patients and correlate outcomes, and we can use this data to correlate practices nationally and internationally. NO DISCLOSURES

Objectives. The main objective of our study was to determine the treatment effect of corticosteroids in peri-radicular infiltration for radicular pain. We also examined whether there was any effect on the need for subsequent interventions such as additional root blocks and/or surgery. Subjects and Method. In a randomised, double blind controlled trial, 150 eligible patients with radicular pain and unilateral symptoms who failed conservative management were randomised for a single injection with bupivacaine and methylprednisolone (b+s) or bupivacaine (b) alone. The outcome measures used included the Oswestry Disability Index (ODI), Low Back Outcome Score (LBOS), Visual Analogue Score (VAS) for leg pain and back pain and patient's subjective level of satisfaction of the outcome. Results. We recruited 76 patients in the b only group and 74 patients in the b+s group. There was no statistically significant difference in the outcome measures between the groups at 3 months (change in ODI [p=0.2], change in VAS [back pain, p=0.28; leg pain, p=0.67]. Subgroup analysis revealed that there was no statistically significant difference in the change in scores between the stenotic group and disc herniation group at 3 months. At 1 year follow-up data was available for 86% of the patients. There was no statistically significant difference in the rate of further interventions in either group. Conclusion. Clinical improvement occurs in both groups of patients. Corticosteroids did not provide additional benefit. There is no difference in the need for further root blocks or surgery

Background. Microdiscectomy involves substantial aggressive excision of disc material from the intervertebral space to prevent reherniation. However, the recent trend is towards conservative disc removal and simple fragment excision (sequestrectomy). Aim. To compare the clinical outcome of microdiscectomy and sequestrectomy. Methods. During the 2-year study period, we performed 196 lumbar microdiscectomies for disc herniation. One hundred and one patients met the inclusion criteria: unilateral single level lumbar disc herniation. Cases suitable for sequestrectomy were based on intraoperative assessment (stable fibrous ring without significant disc bulge; posterior longitudinal ligament perforation of < 5mm). Results. Five patients were lost to follow-up, 72 patients underwent conventional microdiscectomy and 24 patients were suitable for sequestrectomy and included in the final analysis. There was no significant difference in terms of age and pre-operative VAS in both groups (p >0.05, unpaired t test. In the microdiscectomy group, 17/31 patients with motor deficit and 34/66 patients with sensory deficit showed post-operative improvement, but in sequestrectomy group, only 1 of 5 patients with motor deficit and 8 of 13 with sensory deficit recovered but this was not statistically significant (p>0.05, Fisher's exact test). Conclusion. In the sequestrectomy group, patients had significantly better improvement in VAS score. There was no significant difference between either group with regards to reherniation or post-operative neurological deficit. In a selected group of patients with single level lumbar disc herniation, clinical outcome of sequestrectomy is comparable to conventional microdiscectomy

Purpose. To perform an Interrater reliability study determining the agreement between an Orthopaedic team and a Radiology team on the MRI features of prolapsed uncontained cervical discs in Flexion-Distraction injuries of the cervical spine. This leads us to determine how many patients demonstrated evidence of a ‘dangerous’ disc: an uncontained disc herniating posteriorly that may be drawn into the spinal canal during closed reduction. Methods. One hundred and ten patients who had pre-reduction MRI scans managed during the last 10 years were included. Variables were chosen and defined by the senior Author and explained to both teams prior to reviewing the scans. The review was performed by each team independently and without any access to clinical information. Data collection and interpretation was designed by a statistician to reduce risk of data entry errors. Interrater reliability/agreement was determined using the Cohen Kappa value. Results. Disc Protrusion across Posterior Body Line, Interrater agreement Cohen-Kappa=0.46 (moderate agreement) Disc protrusion across Inferior Body Line Interrater agreement Cohen-Kappa=0.4 (moderate agreement) Disc protrusion across Corner to Corner Line, Interrater agreement Cohen-Kappa=0.15 (poor agreement) Disc disruption Line, Interrater agreement Cohen-Kappa=0.33 (moderate agreement) Disc Contained, Interrater agreement Cohen-Kappa=0.41 (moderate agreement) PLL, Interrater agreement Cohen Kappa=0.22 (Fair agreement). Prevalence of posterior disc herniation 42% (orthopaedic team), 51%(Radiology team). Prevalence of uncontained discs 70% (orthopaedic team), 76%(Radiology team). The most agreed upon variables were posterior herniation and the impression of whether the disc was contained. Conclusion. Interrater agreement on the presence of an uncontained herniated disc between Orthopaedic surgeons and Radiologists in this study was never excellent. This leads us to believe it imperative for the surgeon to review MRI's in addition to reading the radiologists report. NO DISCLOSURES

Introduction. The majority of spine patients present with discogenic low back pain, originating from either degenerative disc disease (DDD) or internal disc disruption (IDD). Successful treatment of this patient population relies on obtaining precision diagnosis and careful patient selection, as well as matching the pathology with reliable technology. Total disc replacement (TDR), as an alternative to spinal fusion in the treatment of DDD or IDD, has been studied and reported for several decades in long-term follow-up studies and in several randomized control trials. This prospective study presents a single surgeon experience with two-level CHARITÉ® TDR in 84 consecutive patients, with minimum follow-up of 5 years. The aims of the study were to assess the clinical outcomes of two-level TDR in patients with DDD/IDD. Based on the literature review conducted, this study is considered the largest single surgeon series experience with the two-level CHARITÉ® TDR in the treatment of lumbar DDD, with a minimum follow-up of 5 years reported to date. Materials and Methods. Between January 1997 and March 2006, n=84 consecutive patients underwent two-level TDR for the treatment of two-level DDD or IDD discogenic axial low back pain with or without radicular pain. All patients completed self-assessment outcome questionnaires pre and postoperatively (3, 6, 12 months, and yearly thereafter), including Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMDQ) and Visual Analogue Score (VAS) for back and leg pain. Results. For the n=84 patients, the mean follow-up was 94.34±2.19 months (range = 62–150). The mean age was 49.6±0.94. The mean surgical time was 91±3.16 minutes and the mean blood loss was 207.5±30.62 mls. The main diagnosis was two-level DDD in 63 (76.8%) patients, followed by one-level disc herniation and one-level DDD. Seventy-three (89%) patients underwent L4-5 L5-S1 TDR and 9 (11%) patients underwent L3-4 L4-5 TDR. At all follow-up points, patients demonstrated significant improvement in ODI, RMDQ, and VAS back and leg pain scores compared to pre-operative scores (p < 0.001). The mean improvement between pre-op and last follow-up was 33.3 (66.8%) and 13.23 (74%) for ODI and RMDQ, respectively. Similarly, that was 54.8 (69 %%) and 34.8 (65%) for VAS back and VAS leg pain, respectively. At least 87.8% of the patients rated their satisfaction as good/excellent at any follow-up point. At 5 years follow-up, 54 patients (65.9%) rated their satisfaction as excellent, 19 (23.2%) as good, 7 (8.5%) as satisfactory and 2 (2.4%) as poor. Two patients (2 out of 84, 2.38%) required early revision of one of the prostheses due to failure of indication and/or failure of technique. There has been no device failure. One patient required surgery for adjacent segment disease (1.19%). Conclusion. This study has shown that statistically significant reductions in pain and functional outcomes can be obtained in patients at a minimum follow-up of 5-years following 2-level TDR for the treatment of multilevel DDD or IDD. The clinical benefits of this procedure is supported by the data, with the outcomes reflecting a precision diagnosis, stringent patient selection criteria, and a standardised surgical technique

This study was undertaken to evaluate the safety and efficacy of retrievable inferior vena cava filters in high-risk orthopaedic patients. A total of 58 patients had a retrievable inferior vena cava filter placed as an adjunct to chemical and mechanical prophylaxis, most commonly for a history of previous deep-vein thrombosis or pulmonary embolism, polytrauma, or expected prolonged immobilisation. In total 56 patients (96.6%) had an uncomplicated post-operative course. Two patients (3.4%) died in the peri-operative period for unrelated reasons.

Of the 56 surviving patients, 50 (89%) were available for follow-up. A total of 32 filters (64%) were removed without complication at a mean of 37.8 days (4 to 238) after placement. There were four filters (8%) which were retained because of thrombosis at the filter site, and four (8%) were retained because of incorporation of the filter into the wall of the inferior vena cava. In ten cases (20%) the retrievable filter was left in place to continue as primary prophylaxis. No patient had post-removal thromboembolic complications.

A retrievable inferior vena cava filter, as an adjunct to chemical and mechanical prophylaxis, was a safe and effective means of reducing the acute risk of pulmonary embolism in this high-risk group of patients. Although most filters were removed without complications, thereby avoiding the long-term complications that have plagued permanent indwelling filters, a relatively high percentage of filters had to be left in situ.