The effectiveness and satisfaction of web-based physiotherapy in people with spinal cord injury: a pilot randomised controlled trial.

STUDY DESIGN: A pilot randomised controlled trial. OBJECTIVES: The aims of this study were to evaluate the effectiveness and participant satisfaction of web-based physiotherapy in people with spinal cord injury (SCI). SETTING: Community patients of a national spinal injury unit in a university teaching hospital, Scotland, UK. METHODS: Twenty-four participants were recruited and randomised to receive 8 weeks of web-based physiotherapy (intervention), twice per week, or usual care (control). Individual exercise programmes were prescribed based on participants' abilities. The intervention was delivered via a website (www.webbasedphysio.com) and monitored and progressed remotely by the physiotherapist. RESULTS: Participants logged on to the website an average of 1.4±0.8 times per week. Between-group differences, although not significant, were more pronounced for the 6-min walk test. Participants were positive about using web-based physiotherapy and stated that they would be happy to use it again and would recommend it to others. Overall, it was rated as either good or excellent. CONCLUSIONS: Web-based physiotherapy was feasible and acceptable for people with SCI. Participants achieved good compliance with the intervention and rated the programme highly and beneficial for health and well-being at various states after injury. The results of this study warrant further work with a more homogeneous sample. SPONSORSHIP: This study was funded by the Queen Elizabeth National Spinal Injuries Unit, Glasgow, UK.

Changing demographics of spinal cord injury over a 20-year period: a longitudinal population-based study in Scotland.

STUDY DESIGN: A retrospective cohort study. OBJECTIVES: To review demographic trends in traumatic spinal cord injury (TSCI) and non-traumatic spinal cord injury (NTSCI). SETTING: The Queen Elizabeth National Spinal Injuries Unit (QENSIU), sole provider of treatment for TSCI in Scotland; a devolved region of the UK National Health Service. METHODS: A retrospective review of the QENSIU database was performed between 1994 and 2013. This database includes demographic and clinical data from all new TSCI patients in Scotland, as well as patients with severe NTSCI. RESULTS: Over this 20-year period there were 1638 new cases of TSCI in Scotland; 75.2% occurring in males. TSCI incidence increased non-significantly (13.3 per million population to 17.0), while there were significant increases in mean age at time of TSCI (44.1-52.6 years), the proportion of TSCIs caused by falls (41-60%), the proportion of TSCIs resulting in an American Spinal Injury Association Impairment Scale score of C and D on admission (19.7-28.6% and 34.5-39.5%, respectively) and the proportion of cervical TSCIs (58.4-66.3%). The increase in cervical TSCI was specifically due to an increase in C1-C4 lesions (21.7-31.2%). NTSCI patients (n=292) were 5 years older at injury, more likely to be female (68.1% male) and had a range of diagnoses. CONCLUSION: This study supports the suggestion that demographic profiles in SCI are subject to change. In this population, of particular concern is the increasing number of older patients and those with high level tetraplegia, due to their increased care needs. Prevention programmes, treatment pathways and service provision need to be adjusted for optimum impact, improved outcome and long-term care for their target population.

The influence of central neuropathic pain in paraplegic patients on performance of a motor imagery based Brain Computer Interface.

OBJECTIVE: The aim of this study was to test how the presence of central neuropathic pain (CNP) influences the performance of a motor imagery based Brain Computer Interface (BCI). METHODS: In this electroencephalography (EEG) based study, we tested BCI classification accuracy and analysed event related desynchronisation (ERD) in 3 groups of volunteers during imagined movements of their arms and legs. The groups comprised of nine able-bodied people, ten paraplegic patients with CNP (lower abdomen and legs) and nine paraplegic patients without CNP. We tested two types of classifiers: a 3 channel bipolar montage and classifiers based on common spatial patterns (CSPs), with varying number of channels and CSPs. RESULTS: Paraplegic patients with CNP achieved higher classification accuracy and had stronger ERD than paraplegic patients with no pain for all classifier configurations. Highest 2-class classification accuracy was achieved for CSP classifier covering wider cortical area: 82±7% for patients with CNP, 82±4% for able-bodied and 78±5% for patients with no pain. CONCLUSION: Presence of CNP improves BCI classification accuracy due to stronger and more distinct ERD. SIGNIFICANCE: Results of the study show that CNP is an important confounding factor influencing the performance of motor imagery based BCI based on ERD.

Detection of the motor points of the abdominal muscles.

PURPOSE: Abdominal functional electrical stimulation (AFES) is a technique intended to improve respiratory function in tetraplegia where breathing is affected due to abdominal muscle paralysis. Although it is known that optimal muscle contraction is achieved when electrical stimulation is applied close to the muscle motor point, AFES studies have used a variety of electrode positions. This study aims to investigate the feasibility of using Neuromuscular Electrical Stimulation to detect the motor points of the abdominal muscles, and to evaluate the intrasubject repeatability and intersubject uniformity of their positions, to find the most suitable AFES electrode location. METHODS: Low frequency stimulation (0.5 Hz) was applied to the abdominal muscles of 10 able bodied and five tetraplegic participants. The electrode positions which achieved the strongest muscle contractions were recorded as the motor point positions, with measurements repeated once. For five able bodied participants, assessments were repeated after 18 months, in seated and supine positions. RESULTS: Intersubject uniformity ranged from 2.8 to 8.8%. Motor point positions were identified with intrasubject repeatability of <1.7 cm, deemed adequate relative to standard AFES electrode size. Intrasubject repeatability shows motor point positions changed little (<1.7 cm) after 18 months but varied between seated and supine positions with repeatability of up to 3.1 cm. CONCLUSIONS: A simple technique to locate the motor points of the abdominal muscles is presented and shown to have an adequate intrasubject repeatability, enabling the optimum AFES electrode location to be identified for each user.

Predicting patient-specific rates of bone loss at fracture-prone sites after spinal cord injury.

PURPOSE: People with spinal cord injury (SCI) experience bone loss and have an elevated rate of fracture in the paralysed limbs. The literature suggests an exponential time course of bone loss after SCI, but true rates may vary between patients. We propose systematic evaluation of bone status in the early stages of SCI to identify fast bone losers. METHOD: A case series of six patients with complete SCI were scanned using peripheral quantitative computed tomography within 5 weeks and at 4, 8 and 12 months post-injury. Bone mineral density (BMD) and bone mineral content (BMC) were measured at fracture-prone sites in the tibia and femur. Patient-specific-predictions (PSP) of expected rates of bone loss were produced by individualising published model equations according to each patient's measured values at baseline. Wilcoxon Signed-Rank tests were used to identify changes between time-points; chi-squared tests for differences between measured and PSP values. RESULTS: In the lower limbs, mean values decreased significantly between baseline and 8 months post-injury, by 19-31% for trabecular BMD, 21-32% for total BMD, and 9-29% for BMC. Most subjects showed no significant differences between PSP and measured values, but individuals with significantly faster rates of bone loss than predicted should be investigated further. CONCLUSIONS: There was considerable intersubject variability in rates of bone loss after SCI. Patients showing the fastest bone loss could benefit from continued follow-up and possibly treatment.

A portable gait assessment tool to record temporal gait parameters in SCI.

BACKGROUND: The ability to objectively analyze gait in a clinical environment is challenging due to time, space and cost constraints. This study investigated the validity of a portable gait assessment tool in objectively assessing the temporal gait parameters in subjects with spinal cord injury. The portable gait assessment tool consisted of a pair of insoles instrumented with force sensing resistors that were strategically positioned over the sole of each foot. AIM: To demonstrate the validity of the gait assessment tool by assessing the change in walking ability in incomplete spinal cord injured (ISCI) subjects, who participated in a robot-assisted gait training program. METHODS: Eighteen subjects with either an acute or chronic ISCI participated in this study (age range 26-63 years). Each subject participated in a robot assisted gait training programme for 6 weeks. Assessments were performed using the gait assessment tool before during and after the intervention. RESULTS: The gait assessment tool showed greater sensitivity to the change in the subject's gait, when compared to clinical assessments such as the walking index in spinal cord injury (WISCI II). Subjects with an acute ISCI showed a statistically significant (p<0.05) change in temporal gait parameters within the first 3 weeks of training. DISCUSSION AND CONCLUSION: This study for the first time has used the gait assessment tool in an ISCI population and has demonstrated that gait parameters can be measured and changes can be quantified within a clinical environment. The statistically significant changes during the first 3 weeks of training may indicate that an effective dose of robotic training can be administered within a relatively short period in ISCI subjects during the acute phase.

The metabolic cost of passive walking during robotics-assisted treadmill exercise.

BACKGROUND: We are investigating the potential of robotics-assisted treadmill technology as a mode of exercise in people with spinal cord injury (SCI). People with incomplete SCI can actively contribute to this form of exercise, but in the clinical setting they often walk passively in the system. It is not known whether in doing so they are meeting the recommended guidelines for increasing cardiopulmonary fitness. OBJECTIVE: The aims of this study were twofold: to characterise the intensity of passive walking during robotics-assisted treadmill exercise (RATE) in incomplete SCI; and to determine if this intensity meets the recommended guidelines for cardiopulmonary training in this population. METHODS: 10 subjects with incomplete SCI twice performed an exercise test on a robotics-assisted treadmill. The test comprised a period of passive walking and a ramp phase to the limit of tolerance. Oxygen uptake VO(2) heart rate (HR) were continuously measured. RESULTS: VO(2) during passive exercise was on average 1.4 times higher than resting VO(2R), but this was only 29% of peak VO(2) (VO(2 peak))(range 16-43%). Relative to rest, passive VO(2) (VO(2P) was only 12% of VO(2 peak). HR did not increase from rest to passive walking (81 ± 10 bpm to 81 ± 13 bpm respectively). The HR associated with passive walking was on average 50% of peak HR (HR(peak)) (161 ± 13 bpm). Test-retest reliability was moderate for VO(2R) (R=0.62) and resting HR (HR(R)) (R=0.68), high for VO(2P) (R=0.81), passive HR (HR(P)) (R=0.87) and HR(peak) (R=0.88), and very high (R=0.95) for VO(2 peak). Only HR(p) differed significantly between tests (p=0.029). CONCLUSIONS: The intensity of passive walking during RATE is low and is insufficient to increase cardiopulmonary fitness in people with SCI. Subjects must actively contribute to the exercise in order to achieve the recommended training intensity.

Functional outcome and discharge destination in elderly patients with spinal cord injuries.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To describe functional outcome and discharge destination of elderly patients with traumatic spinal cord injuries. SETTING: National Spinal Injuries Unit, Glasgow, UK. METHODS: We collected data for 5 years on all patients >65 years old with a traumatic spinal cord injury treated at the National Spinal Injuries Unit. RESULTS: We identified 39 patients. Of these, nine patients died during admission; all had cervical spine injuries. The mean age of the 30 survivors was 73 years (range 65-88). The most common cause of injury was a fall: 26 patients (87%). In addition, 21 (70%) sustained injury to cervical cord, 3 (10%) had thoracic and 6 (20%) had lumbar spine fractures. In all, 23 patients (77%) were treated by orthosis and 7 (23%) underwent surgical intervention. Twelve (40%) patients showed an improvement in American Spinal Injury Association impairment scale. The median hospital stay was 136 days. Thus, 11 patients (37%), all with incomplete injuries, were discharged home, 10 (33%) were transferred to nursing homes/community hospitals and 9 patients (30%) were discharged back to the referring hospital, while they were awaiting adjustments at home. Patients who were discharged home had significantly higher Functional Independence Measure scores, both at the onset of rehabilitation and at discharge, than those who were discharged to a nursing home or other hospitals (P<0.01 and <0.001, respectively). DISCUSSION AND CONCLUSION: Although the elderly patients may benefit from the services of a dedicated spinal injuries centre, they should be carefully selected. The patient, relatives as well as the referring doctors should be alerted to the likely long-term outcomes early in the course of the injury. Elderly patients with complete lesions of the spinal cord will almost certainly remain institutionalized. Early endeavour should be made to find alternate rehabilitation settings with a lower-intensity treatment.

Development of quantitative and sensitive assessments of physiological and functional outcome during recovery from spinal cord injury: a clinical initiative.

The ability to detect physiological changes associated with treatments to effect axonal regeneration, or novel rehabilitation strategies, for spinal cord injury will be challenging using the widely employed American Spinal Injuries Association (ASIA) impairment scales (AIS) for sensory and motor function. Despite many revisions to the AIS standard neurological assessment, there remains a perceived need for more sensitive, quantitative and objective outcome measures. The purpose of Stage 1 of the Clinical Initiative was to develop these tools and then, in Stage 2 to test them for reliability against natural recovery and treatments expected to produce functional improvements in those with complete or incomplete spinal cord injury (SCI). Here we review aspects of the progress made by four teams involved in Stage 2. The strategies employed by the individual teams were (1) application of repetitive transcranial magnetic stimulation (rTMS) to the motor cortex in stable (chronic) SCI with intent to induce functional improvement of upper limb function, (2) a tele-rehabilitation approach using functional electrical stimulation to provide hand opening and grip allowing incomplete SCI subjects to deploy an instrumented manipulandum for hand and arm exercises and to play computer games, (3) weight-assisted treadmill walking therapy (WAT) comparing outcomes in acute and chronic groups of incomplete SCI patients receiving robotic assisted treadmill therapy, and (4) longitudinal monitoring of the natural progress of recovery in incomplete SCI subjects using motor tests for the lower extremity to investigate strength and coordination.

Kinematic modelling of a robotic gait device for early rehabilitation of walking.

Rehabilitation of walking is an essential element in the treatment of incomplete spinal cord injured (SCI) patients. During the early post injury period, patients find it challenging to practice upright walking. Simulating stepping movements in a supine posture may be easier and promote earlier rehabilitation. A robotic orthotic device for early intervention in spinal cord injury that does not require the patient to be in an upright posture has been modelled. The model comprises a two-bar mechanical system that is configured and powered to provide limb kinematics that approximate normal overground walking. The modelling work has been based on gait analysis performed on healthy subjects walking at 50 per cent, 75 per cent, and 100 per cent of normal cadence. Simulated angles of hip, knee, and ankle joints show a comparable range of motion (ROM) to the experimental walking data measured in healthy subjects. The model provides operating parameters for a prospective recumbent gait orthosis that could be used in early walking rehabilitation of incomplete SCI patients.

Delayed presentation and diagnosis of cervical spine injuries in long-standing ankylosing spondylitis.

Patients with ankylosing spondylitis (AS) are vulnerable to cervical spine fractures. Long-standing pain may mask the symptoms of the fracture. Radiological imaging of the cervical spine may fail to identify the fracture due to the distorted anatomy, ossified ligaments and artefacts leading to delay in diagnosis and increased risk of neurological complications. The objectives are to identify the incidence and risk factors for delay in presentation of cervical spine fractures in patients with AS. Retrospective case series study of all patients with AS and cervical spine fracture admitted over a 12-year period at Queen Elizabeth National Spinal Injuries Unit, Scotland. Results show that total of 32 patients reviewed with AS and cervical spine fractures. In 19 patients (59.4%), a fracture was not identified on plain radiographs. Only five patients (15.6%) presented immediately after the injury. Of the 15 patients (46.9%) who were initially neurologically intact, three patients had neurological deterioration before admission. Cervical spine fractures in patients with long-standing AS are common and usually under evaluated. Early diagnosis with appropriate radiological investigations may prevent the possible long-term neurological cord damage.

Muscle and bone adaptations after treadmill training in incomplete Spinal Cord Injury: a case study using peripheral Quantitative Computed Tomography.

We describe the use of peripheral Quantitative Computed Tomography (pQCT) to identify musculoskeletal responses to partial body-weight supported treadmill training (BWSTT) in incomplete spinal cord injury (SCI). Long-term health consequences of SCI include extensive muscle atrophy, severe bone loss and an increased fracture risk in the affected limbs, mostly at both tibial epiphyses and the distal femoral epiphysis. Regular treadmill training may slow or reverse bone loss by recruiting available lower-limb musculature and loading the leg bones dynamically. The potential for detailed analysis of musculoskeletal changes using pQCT is illustrated with a single case study (14.5 years post-SCI), who completed seven months of partial BWSTT. Pre- and post-training lower-limb pQCT scans were taken to quantify changes in trabecular bone, cortical bone, and soft-tissue. Trabecular bone mineral density increased by 5% (right) and 20% (left) in the distal tibia. Changes in proximal tibia and distal femur were negligible. Increases in muscle cross-sectional area were 6% (right) and 12% (left) in the lower leg, 7% (right) and 5% (left) in the thigh. We suggest that treadmill training may lead to positive musculoskeletal adaptations at clinically-relevant sites. Such changes can be measured in detail using pQCT.

Automatic electrical stimulation of abdominal wall muscles increases tidal volume and cough peak flow in tetraplegia.

Paralysis of the respiratory muscles in people with tetraplegia affects their ability to breathe and contributes to respiratory complications. Surface functional electrical stimulation (FES) of abdominal wall muscles can be used to increase tidal volume (V_{T}) and improve cough peak flow (CPF) in tetraplegic subjects who are able to breathe spontaneously. This study aims to evaluate the feasibility and effectiveness of a novel abdominal FES system which generates stimulation automatically, synchronised with the subjects' voluntary breathing activity. Four subjects with complete tetraplegia (C4-C6), breathing spontaneously, were recruited. The automatic stimulation system ensured that consistent stimulation was achieved. We compared spirometry during unassisted and FES-assisted quiet breathing and coughing, and measured the effect of stimulation on end-tidal CO_2 (EtCO_2) during quiet breathing. The system dependably recognised spontaneous respiratory effort, stimulating appropriately, and was well tolerated by patients. Significant increases in V_T during quiet breathing (range 0.05-0.23 L) and in CPF (range 0.04-0.49 L/s) were observed. Respiratory rate during quiet breathing decreased in all subjects when stimulated, whereas minute ventilation increased by 1.05-2.07 L/min. The changes in EtCO_2 were inconclusive. The automatic stimulation system augmented spontaneous breathing and coughing in tetraplegic patients and may provide a potential means of respiratory support for tetraplegic patients with reduced respiratory capacity.

Late dislocation after total hip arthroplasty.

OBJECTIVES: Instability after total hip arthroplasty is a troublesome complication. It commonly occurs in the first 3 postoperative months, but the risk continues over time. There are numerous treatment options, but they have relatively unpredictable outcomes. Numerous factors have been associated with dislocation, but research has mainly focused on the surgical ones. Epidemiological factors remain the subject of much debate. We aimed to establish the incidence of dislocation over time. METHODS: The Scottish National arthroplasty non-voluntary registry is based on SMR01 records (Scottish Morbidity Record) data. We analyzed the Scottish National Arthroplasty Project to find patients' dislocation rates. RESULTS: There were 62,175 total hip arthroplasties performed from April 1989 to March 2004 with an annual incidence of dislocation of 0.9%. We found no increase in the rate of dislocation after 2 years. CONCLUSIONS: It appears there is no late increase in dislocation rate. LEVEL OF EVIDENCE: Prognostic study, level II-1 (prospective study).

Arm-cranking exercise assisted by Functional Electrical Stimulation in C6 tetraplegia: a pilot study.

Tetraplegic volunteers undertook progressive exercise training, using novel systems for arm-cranking exercise assisted by Functional Electrical Stimulation (FES). The main aim was to determine potential training effects of FES-assisted arm-crank ergometry (FES-ACE) on upper limb strength and cardiopulmonary (fitness) in tetraplegia. Surface FES was applied to the biceps and triceps during exercise on an instrumented ergometer. Two tetraplegic volunteers with C6 Spinal Cord Injury (SCI) went through muscle strengthening, baseline exercise testing and three months of progressive FES-ACE training. Repeat exercise tests were carried out every four weeks during training, and post-training, to monitor upper-limb strength and cardiopulmonary fitness. At each test point, an incremental test was carried out to determine peak work rate, peak oxygen uptake, gas exchange threshold and oxygen uptake-work rate relationship during FES-ACE. Peak oxygen uptake for Subject A increased from 0.7 l/min to 1.1 l/min, and peak power output increased from 7 W to 38 W after FES-ACE training. For Subject B, peak oxygen uptake was unchanged, but peak power output increased from 3 W to 8 W. These case studies illustrate potential benefits of FES-ACE in tetraplegia, but also the differences in exercise responses between individuals.

A treadmill control protocol combining nonlinear, equally smooth increases in speed and gradient: exercise testing for subjects with gait and exercise limitations.

Incremental exercise testing with a linear increase in work rate is the recommended method for clinical exercise testing. A recent protocol (A), incorporating a linear increase in speed and a nonlinear increase in gradient, has been developed which addresses some limitations of traditional testing methods. It does not account for those with an impaired gait pattern. We propose and assess a novel protocol (B) incorporating nonlinear increases in both speed and gradient. We theoretically develop a new treadmill control protocol (B), determine oxygen uptake response linearity, initial metabolic rate and cardiopulmonary response parameters (peak oxygen uptake, lactate threshold, dynamic O2 cost) and compare the outcome measures with two previously verified IET protocols (A and C (constant speed with linear increase in gradient)). Feasibility and outcomes were explored with a subject with incomplete spinal cord injury. The average initial metabolic rate (VO2) was substantially lower during protocol A (0.49 (+/-0.12) l min(-1)) and protocol B (0.52 (+/-0.05) l min(-1)) than during protocol C (1.35 (+/-0.04) l min(-1)). The average linearity of the VO2 response during protocols A and B (correlation co-efficients 0.97 (+/-0.00) and 0.95 (+/-0.02), and co-efficients of determination 0.94 (+/-0.01) and 0.91 (+/-0.02), respectively) were higher than during protocol C (correlation co-efficient 0.91 (+/-0.02) and co-efficient of determination 0.84 (+/-0.02)). The average dynamic O2 cost for protocol C (6.53 (+/-0.46) ml min(-1)W(-1)) was lower than that of protocol A (10.02 (+/-1.16) ml min(-1) W(-1)) and protocol B (10.03 (+/-0.91) ml min(-1) W(-1)). No differences were found in these parameters between protocols A and B. The new protocol B performs better than protocol C and is comparable with protocol A. When testing subjects with an impaired gait pattern, it may be advantageous to use the new protocol B due to the gradual increases in both speed and gradient throughout the test.

Energetics of paraplegic cycling: a new theoretical framework and efficiency characterisation for untrained subjects.

Complete lower-limb paralysis resulting from spinal cord injury precludes volitional leg exercise, leading to muscle atrophy and physiological de-conditioning. Cycling can be achieved using phased stimulation of the leg muscles. With training there are positive physiological adaptations and health improvement. Prior to training, however, power output may not be sufficient to overcome losses involved in rotating the legs and little is known about the energetics of untrained paralysed muscles. Here we propose efficiency measures appropriate to subjects with severe physical impairment performing cycle ergometry. These account for useful internal work (i.e. muscular work done in moving leg mass) and are applicable even for very low work rates. Experimentally, we estimated total work efficiency of ten untrained subjects with paraplegia to be 7.6 +/- 2.1% (mean +/- SD). This is close to values previously reported for anaesthetised able-bodied individuals performing stimulated cycling exercise, but is less than 1/3 of that of able-bodied subjects cycling volitionally. Correspondingly, oxygen cost of the work (38.8 +/- 13.9 ml min(-1) W(-1)) was found to be approximately 3.5 times higher. This indicates the need, for increased power output from paralysed subjects, to maximise muscle strength through training, and to improve efficiency by determining better methods of stimulating the individual muscles involved in the exercise.

A control system for automatic electrical stimulation of abdominal muscles to assist respiratory function in tetraplegia.

People with tetraplegia have poor respiratory function leading to limited tidal volume (V(T)) and reduced cough peak flow (CPF). These problems may cause respiratory failure during the initial admission or subsequent intercurrent illness. Electrical stimulation of the abdominal muscles during expiration can improve respiratory function by increasing V(T) and CPF. We developed a novel control system to automatically trigger muscle stimulation, synchronised with the subject's voluntary respiratory activity. The system was tested in four subjects with a functionally complete lesion at level C4 to C6, aged between 16 and 46 years, 3 months to 5 years post injury, who were breathing spontaneously. The algorithm delivered automatic stimulation patterns, detecting cough and quiet breathing while suppressing stimulation during other activities such as speaking. Marked increases in V(T) (between 9% and 71% of baseline) and CPF (between 31% and 54% of baseline) were observed, suggesting that the technique may have potential use in both acute and established tetraplegia to increase minute ventilation and to improve cough clearance of secretions.

Blunt cervical spine trauma as a cause of spinal cord injury and delayed cortical blindness.

STUDY DESIGN: Case report. OBJECTIVE: To present and discuss the case of a patient who sustained a significant flexion compression injury of the cervical spine with resulting tetraplegia and development of cortical blindness. SETTING: National Spinal Injuries Unit and Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland, UK. METHODS: Clinical and radiological follow-up of the patient. RESULTS: Cortical blindness resulted from vertebral artery dissection associated with blunt cervical spine trauma. The patient is registered blind and is ventilator dependent. CONCLUSION: The potential complications of blunt vertebral artery injury remain poorly recognised. Screening is routinely not performed. Advances in noninvasive radiological techniques may result in recognition of asymptomatic disease and the potential for therapeutic intervention.

Epidemiology of dislocation after total hip arthroplasty.

Instability after total hip arthroplasty is an important complication. It usually occurs in the immediate postoperative period, but the risk also increases with time. There are numerous surgical treatment options, but they have relatively unpredictable outcomes. Numerous factors are associated with dislocation, but research has mainly focused on surgical factors. Epidemiological factors remain the subject of much debate. We aimed to establish the most significant epidemiological factors in Scotland and in particular the dislocation rate in neuromuscular conditions. The Scottish National arthroplasty nonvoluntary registry is based on SMR01 records (Scottish Morbidity Record) data. We analyzed the Scottish National Arthroplasty Project to find patients' dislocation rates up to 1 year postoperatively for surgeon volume, age, gender, previous surgery, diagnosis, and followup duration. There were 14,314 total hip arthroplasties performed from April 1996 to March 2004 with an annual incidence of dislocation of 1.9%. We found an association between rate of dislocation with age, surgical volume, and previous fracture. However, there was no increase in the rate of dislocation associated with gender or with diagnoses of stroke or Parkinson's disease. Our prognostic assessment of dislocation risk allows assessment for methods of reducing dislocation in high risk patients.