Introduction. Studies have addressed the issue of increasing prevalence of work-related musculoskeletal (MSK) pain among different occupations. However, contributing factors to MSK pain have not been fully investigated among orthopaedic surgeons. Thus, this study aimed to approximate the prevalence and predictors of MSK pain among Saudi orthopaedic surgeons working in Riyadh, Saudi Arabia. Methods. A cross-sectional study using an electronic survey was conducted in Riyadh. The questionnaire was distributed through email among orthopaedic surgeons in Riyadh hospitals. Standardized Nordic questionnaires for the analysis of musculoskeletal symptoms were used. Descriptive measures for categorical and numerical variables were presented. Student’s t-test and Pearson’s χ2 test were used. The level of statistical significance was set at p ≤ 0.05. Results. The response rate was 80.3%, with a total number of 179 of Saudi orthopaedic surgeons (173 males and six females). Of our sample, 67.0% of the respondents complained of having MSK pain. The most commonly reported MSK pain was lower back (74.0%), followed by neck (58.2%). Age and body mass index were implicated in the development of more than one type of MSK pain. Increased years of experience (≥ 6 years) was linked to shoulder/elbow, lower back, and hip/thigh pain. Smoking is widely associated with lower back pain development, whereas physicians who do not smoke and exercise regularly reported fewer pain incidences. Excessive bending and twisting during daily practice have been correlated with increased neck pain. Conclusion. MSK pain was found to be common among Saudi orthopaedic surgeons. Further extensive research should be conducted to understand and analyze the risk factors involved and search for possible improvements to avoid further complications. However, ergonomics education during surgical training could be effective at modifying behaviors and reducing MSK pain manifestations

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

The NDI is a simple 10-item questionnaire used to assess patients with neck pain. The original validation was performed on 52 patients with neck pain and the test-retest on 17 whiplash patients with a 2-day interval. The SF36 measures functional ability, wellbeing and the overall health of patients. It is used in health economics to assess the health utility, gain and economic impact of medical interventions. Objectives were to independently validate the NDI in patients with neck pain and to draw comparison between the NDI and SF36. 160 patients with neck pain attending the spinal clinic completed self-assessment questionnaires. A second questionnaire was completed in 34 patients after a period of 1-2 weeks. The internal consistency of the NDI and SF36 was calculated using Cronbach alpha. The test-retest reliability was assessed using the Bland and Altman method and the concurrent validity between the two questionnaires was assessed using Pearson correlation. Both questionnaires showed robust internal consistency: SF36 alpha = 0.878 (se=0.014, 95%CI=0.843 to 0.906) and NDI = 0.864 (se=0.017, 95%CI=0.825 to 0.894). The NDI had significant correlation to all eight domains of the SF36 (p<0.001). The individual scores for each of the ten items had significant correlation with the total disability score (p<0.001). The test-retest reliability of the NDI was acceptable. We have shown irrefutably that the NDI has good reliability and validity and that it stands up well to the SF36

Cervical spinal arthrodesis is the standard of care for the treatment of spinal diseases induced neck pain. However, adjacent segment disease (ASD) is the primary postoperative complication, which draws great concerns. At present, controversy still exists for the etiology of ASD. Knowledge of cervical spinal loading pattern after cervical spinal arthrodesis is proposed to be the key to answer these questions. Musculoskeletal (MSK) multi-body dynamics (MBD) models have an opportunity to obtain spinal loading that is very difficult to directly measure in vivo. In present study, a previously validated cervical spine MSK MBD model was developed for simulating cervical spine after single-level anterior arthrodesis at C5-C6 disc level. In this cervical spine model, postoperative sagittal alignment and spine rhythms of each disc level, different from normal healthy subject, were both taken into account. Moreover, the biomechanical properties of facet joints of adjacent levels after anterior arthrodesis were modified according to the experimental results. Dynamic full range of motion (ROM) flexion/extension simulation was performed, where the motion data after arthrodesis was derived from published in-vivo kinematic observations. Meanwhile, the full ROM flexion/extension of normal subject was also simulated by the generic cervical spine model for comparative purpose. The intervertebral compressive and shear forces and loading-sharing distribution (the proportions of intervertebral compressive and shear force and facet joint force) at adjacent levels (C3-C4, C4-C5 and C6-C7 disc levels) were then predicted. By comparison, arthrodesis led to a significant increase of adjacent intervertebral compressive force during the head extension movement. Postoperative intervertebral compressive forces at adjacent levels increased by approximate 20% at the later stage of the head extension movement. However, there was no obvious alteration in adjacent intervertebral compressive force, during the head flexion movement. For the intervertebral shear forces in the anterior-posterior direction, no significant differences were found between the arthrodesis subject and normal subject, during the head flexion/extension movement. Meanwhile, cervical spinal loading-sharing distribution after anterior arthrodesis was altered compared with the normal subject's distribution, during the head extension movement. In the postoperative loading-sharing distribution, the percentage of intervertebral disc forces was further increased as the motion angle increased, compared with normal subject. In conclusion, cervical spinal loading after anterior arthrodesis was significantly increased at adjacent levels, during the head extension movement. Cervical spine musculoskeletal MBD model provides an attempt to comprehend postoperative ASD after anterior arthrodesis from a biomechanical perspective

Minimally invasive (MIS) screw fixation for Hangman's fracture can decrease iatrogenic soft-tissue injury compared with conventional open approach, but increase the risk of instrumentation-related complications due to lack of anatomical landmarks. With the advantages, the intra-operative three-dimensional fluoroscopy-based navigation (ITFN) system seems to be an inherent partner for MIS techniques. The purpose of this study was to evaluate the accuracy and feasibility of MIS techniques incorporating with ITFN for treating Hangman's fracture. 20 patients with Hangman's fracture underwent C2-C3 pedicle screw fixation using ITFN. 6 patients used MIS technique, with the other 14 patients using conventional open technique. Preoperative visual analogue score (VAS) was 5.7±1.4 in CAOS-MIS group and 5.5±0.9 in CAOS-open group. Operative time, blood loss and postoperative neurovascular complications were recorded. The accuracy of screw positions was studied by postoperative CT scan. All patients were followed up for at least 6 months and the fusion status was ascertained by dynamic radiographs. The average operative time was 134.2±8.0 min in CAOS-MIS group and 139.3±25.8 min in CAOS-open group, and there was no significant difference between the two (p&gt;0.01). The blood loss was 66.7±25.8 ml in CAOS-MIS group and 250.0±141.4 ml in CAOS-open group. Statistical difference existed with CAOS-MIS group significant less than CAOS-open group (p&lt;0.01). A total of 80 screws were inserted. No screw-related neurovascular injury was observed. Post-operative CT scan revealed 83.3% (20/24) screws of grade 1 and 16.7% screws of grade 2 (4/24) in CAOS-MIS group, meanwhile 89.3% screws of grade 1 (50/56) and 10.7% screws of grade 2 (6/56) in CAOS-open group. There was no grade 3 screw detected. Fisher's exact test showed there was no statistical difference between these two groups (p&gt;0.01). There was no statistical difference in pre-operative VAS between these two groups (p&gt;0.01). Compared with the CAOS-open group (1.7±0.6), neck pain VAS at 6-month follow-up in CAOS-MIS group (0.3±0.5) was significantly lower (p&lt;0.01). Solid fusion was demonstrated in all the cases by dynamic radiographs. So it is feasible and safe for percutaneous minimally invasive C2-C3 pedicle screw fixation for Hangman's fracture using intra-operative three-dimensional fluoroscopy-based navigation, which can also decrease the incidence of post-operative neck pain

Surgical interventions for the treatment of chronic neck pain, which affects 330 million people globally, include fusion and cervical total disc replacement (CTDR). Most of the currently clinically available CTDRs designs include a metal-on-polymer (MoP) bearing. Numerous studies suggest that MoP CTDRs are associated with issues similar to those affecting other MoP joint replacement devices, including excessive wear and wear particle-related inflammation and osteolysis. A standard ISO testing protocol was employed to investigate a device with a metal-on-metal (MoM) bearing. Moreover, with findings in the literature suggesting that the testing protocol specified by ISO-18192-1 may result in overestimated wear rates, additional tests with reduced kinematics were conducted. Six MoM CTDRs made from high carbon cobalt-chromium (CoCr) were tested in a six-axis spine simulator, under the ISO-18192-1 protocol for a duration of 4 million cycles (MC), followed by 2MC of modified testing conditions, which applied the same axial force as specified in ISO-18192-1 (50-150N), but reduced ranges of motion (ROM) i.e. ±3° flexion/extension (reduced from ±7.5°) and ±2° lateral bending (reduced from ±6°) and axial rotation (reduced from ±4°). Foetal bovine serum (25% v/v), used as a lubricant, was changed every 3.3×10. 5. cycles and stored at −20°C for particle analysis. Components were measured after each 1×10. 6. cycles; surface roughness, damage modes and gravimetric wear were assessed. The wear and roughness data was presented as mean ±95% confidence interval and was analysed by one-way analysis of variance (ANOVA) (p=0.05). The mean wear rate of the MoM CTDRs tested under the ISO protocol was 0.246 ± 0.054mm. 3. /MC, with the total volume of wear of 0.977 ± 0.102mm. 3. lost over the test duration (Fig. 1). The modified testing protocol resulted in a significantly lower mean volumetric wear rate of 0.039 ± 0.015mm. 3. /MC (p=0.002), with a total wear volume of 0.078 ± 0.036mm. 3. lost over the 2MC test duration. Under both test conditions, the volumetric wear was linear; with no significant bedding-in period observed (Fig. 1). The mean pre-test surface roughness decreased from 0.019 ± 0.03µm to 0.012 ± 0.002µm (p=0.001) after 4MC of testing, however surface roughness increased to 0.015 ± 0.002µm (p=0.009) after the additional 2MC of modified test conditions. Following 4MC of testing, polishing marks, observed prior to testing, had been removed. Consistently across all components, surface discolouration and multidirectional, criss-crossing, curvilinear and circular wear tracks, caused by abrasive wear, were observed. Reduced ROMs testing caused similar types of damage, however the circular wear tracks were smaller in size, compared to those produced during testing under the ISO protocol. The wear rates exhibited by MoM CTDRs tested under ISO-18192-1 testing protocol (0.246mm. 3. /MC) were lower, when compared to CTDR designs incorporating MoP bearings, as well as MoM lumbar CTDRs. Wear rates generated under a modified ISO testing protocol were reduced tenfold, similarly to findings that have previously been reported in the literature, and support the hypothesis that the testing protocol specified by ISO-18192-1 may overestimate wear rates. Characterisation of particles generated by MoM CTDRs and biological consequences of those remain to be determined. For figures/tables, please contact authors directly.

We analysed the morbidity, mortality and outcome of cervical spine injuries in patients over the age of 65 years in a retrospective review of 107 elderly patients admitted to our tertiary referral spinal injuries unit with cervical spine injuries between 1994 and 2002. The data were acquired by analysis of the national spinal unit database, hospital inpatient enquiry (HIPE) system, chart and radiographic review. Mean age was 74 years (range 66-93yrs). The male to female ratio was 2.1: 1(M=72, F=35). The mean follow-up was 4.4 years (1-9 years) and mean in-hospital stay was 10 days. The mechanism of injury was a fall in 75 and a road traffic accident (RTA) in the remaining 32 patients. The overall complication rate was 18.6% with an associated in-hospital mortality of 11.2%. Outcome was assessed using the Cervical Spine Outcomes Questionnaire (CSOQ) from Johns Hopkins School of Medicine. Functional outcome scores approached pre-morbid level in almost all patients. Functional disability was more marked in the patients with neurological deficit at the time of injury. Outcome of the injury is related to the increasing age, co-morbidity and the severity of the neurological deficit. Injuries of the cervical spine are a not infrequent occurrence in the elderly and occur with relatively minor trauma. Neck pain in the elderly patient should be thoroughly evaluated to exclude C2 injuries. Most patients can be managed in an orthosis but unstable injuries require rigid external immobilisation

Background. The factors that are considered to be associated with successful clinical outcome fallowing cervical arthroplasty surgery are patient selection, absence of facet joint changes and lack of pre-operative kyphosis. Even though many studies have cited the pre-operative demographic details of their patient groups, the effect of associated psychological co-morbidities (Depression/Anxiety), smoking history, gender, social benefits and employment status on the clinical outcome measures have not been reported. The aim of the study was to assess the influence of pre-operative patient characteristics on the clinical outcomes following cervical disc replacement. Methods. We included 126 patients who underwent single or multiple level cervical arthroplasty in our unit were included in the study. The clinical outcome measures such as Visual Analogue Score for neck pain (VAS-NP) and arm pain (VAS-AP); Neck disability Index (NDI), Hospital depression and anxiety scale and Bodily pain component of Short Form 36 questionnaires (SF-36 P) were recorded pre and post operatively. Statistical analysis was completed using SPSS 16.0 statistical package (SPSS Inc, Chicago, IL). Results. There were 60 males and 63 females. Average duration of follow up was 18 months (Range 10–51). Out of 123 patients, 37 patients had a history of anxiety/depression, 25 patients gave history of smoking, 64 were actively working at the time of operation and 27 were receiving social benefits. We have found that gender; smoking status, associated co-morbidities, working and benefit status had no statistically significant contribution to clinical outcome measures in the follow up period. Conclusion. This is has been a first ever attempt to analyse the affect these psychosocial factors on the clinical outcomes following cervical arthroplasty. In our study, contrary to studies related lumbar surgeries, we conclude that there is no statistically significant contribution of associated psychosocial factors on the clinical outcomes in the early follow up period

Introduction. In the last decade, single level cervical arthroplasty has proven its efficacy as one of the surgical treatment option for for patients suffering from cervical degenerative disc disease. Recent published reports on multilevel cervical arthroplasty using single implants have shown statistically significant results when compared to single level surgery. The aim of this study is to compare the clinical outcomes of multilevel cervical arthroplasty to single level cervical arthroplasty, when more than one type of implants were used. Methods. This is a prospective study of consecutive patients who presented to our unit in between June 2006 and November 2009. The maximum follow-up period was 51 months (mean=18 months). Several types of cervical arthroplasty devices have been used in this study. The clinical outcome measures such as Visual Analogue Score for neck pain (VAS-NP) and arm pain (VAS-AP); Neck disability Index (NDI) and the Bodily pain component of Short Form 36 questionnaires were recorded pre and post operatively. After confirming the normality of the data appropriate parametric (paired t-test) were used to assess the statistical significance (p< 0.05) between pre and post-operative values. Two sample T-test was used to assess the significance between the differences in mean scores between each group. Results. A total of 105 patients (37 single level, 68 multi-level) were included in the study. Mean age of patients was 51 years (Range 32–80) with Male: Female ratio of 9:10. All clinical outcome measures showed statistically significant improvement in the post-operative period in single as well as multilevel group. However, there was no statistically significant difference in the improvement in between single and multilevel surgeries. Conclusions. Our study results clearly demonstrate that multilevel cervical arthroplasty offers the similar clinical outcome when compared to single level surgery, despite using different type of implant in multilevel surgeries

Study Design. Prospective cohort study. Objective. To assess the safety and efficacy of an intra-operative gamma probe in the surgical treatment of osteoid osteomas and osteoblastomas arising from the spine. Summary of background data. Spinal osteoid osteomas and osteoblastomas are difficult to localise and may present adjacent to neural structures. Complete surgical excision of the nidus is a pre-requisite for curative resection. Methods. All patients with a presumptive diagnosis of osteoid osteoma or osteoblastoma were investigated with plain radiography, computed tomography, magnetic resonance imaging and a technitium bone scan. Nine patients underwent surgical excision. 600 MBq of 99m technitium HMDP was administered intravenously three hours prior to surgery. A sterile cadmium telluride detector connected to a digital counter/ratemeter was used to detect gamma radiation emitted by the tumour intra-operatively to assist with localisation and confirmation of complete excision. Results. Between October 1995 and September 2006, nine patients required surgical excision for seven osteoid osteomas and two osteoblastomas arising from the spine. All patients were between the ages of 9-31 years and presented with back or neck pain. All tumours involved the posterior elements of the spine. Three patients had previous failed treatment including CT-guided radiofrequency ablation and surgical excision. In all cases the counts per second (cps) dropped significantly following excision. Histological examination confirmed complete excision in all cases. The mean follow-up was 4.5 years (range 0.5-11 years). All patients reported disappearance of the characteristic pre-operative pain. Conclusions. The use of an intra-operative gamma probe helps to localise and confirm complete excision of osteoid osteoma and osteoblastoma arising from the spine. Accurate localisation results in safe excision with maximal conservation of surrounding normal bone, whilst minimising operative time, blood loss, hospital stay and risk of recurrence

Neck pain can be caused by pressure on the spinal cord or nerve roots from bone or disc impingement. This can be treated by surgically decompressing the cervical spine, which involves excising the bone or disc that is impinging on the nerves or widening the spinal canal or neural foramen. Conventional practise is to fuse the adjacent intervertebral joint after surgery to prevent intervertebral motion and subsequent recompression of the spinal cord or nerve root. However fusion procedures cause physiological stress transfer to adjacent segments which may cause Adjacent Segment Degeneration (ASD), a rapid degeneration of the adjacent discs due to increased stress. ASD is more likely to occur in fusions of two or more levels than single level fusions and is more common where there is existing degeneration of the adjacent discs, which is not unusual in people over 30 years of age. Partial dynamic stabilisation, which generally involves a semi-rigid spinal fixation, allows a controlled amount of intervertebral motion (less than physiological, but more than fusion) to prevent increased stress on the adjacent segments (potentially preventing ASD) whilst still preventing neural recompression. Partial dynamic stabilisation is suitable for treating spinal instability after decompression as well as certain degenerative instabilities and chronic pain syndromes. Dynamic stabilisation and semi-rigid fixation systems for the spine are typically fixated posteriorly. However, choice of posterior surgical stabilisation techniques in the cervical spine is limited due to the size of the osseous material available for fixation and the close proximity of the neural structures and the vertebral artery. Posterior dynamic stabilisation systems for stabilisation of the lumbar spine often use the pedicle as an anchor point. Using the pedicle of the cervical spine as an anchor point is technically difficult because of its small size, angulation and proximity to neurovascular structures. Therefore, one of the main challenges to provide stabilisation in the cervical spine is the limitations of the anatomy. This presentation will introduce a novel spinal implant (patent pending) which is proposed for the cervical spine to provide partial dynamic stabilisation in the C3 to T1 region from a posterior approach. The implant is a single unit with a safe and technically simple insertion technique into the lateral masses. The implant uses a simple mechanism to allow limited intervertebral motion at each instrumented level. It is hoped that the simplicity of the device and removing the need to provide a bone graft anteriorly may reduce the cost of the procedure compared to traditional fusion and competing surgeries