Magnetic Resonance Imaging is increasingly utilised for the assessment of knee pathology. The aim of this study was to review our entire knee MRI scans and to assess the accuracy of diagnosis when compared with operative diagnosis. Using data from the radiology department and medical records (public and private) all patients having knee MRI scans in a 6-year period were identified. There were 956 scans performed on 930 patients. Scan diagnosis, operative diagnosis and diagnostic accuracy were assessed. Of the scanned patients 181 (19.5%) had normal scans and of these 168 (92.8%) were accurately diagnosed as normal. The remaining 749 (80.5%) had an abnormality noted on scan and of these 298 (39.8%) proceeded on to surgery. Of those patients having surgery, diagnosis at surgery was found to exactly match the results of the scan in 163 (57.0%) patients. Furthermore 51.5% of patients with a diagnosis of meniscal degeneration by scan actually had a meniscal tear at operation. However the sensitivity for diagnosis of ACL tears was 89.0% and that of medial meniscal tears was 90.6%. MRI diagnosis is far from infallible and clinicians should be conscious of its limitations. However it is particularly reliable in confirming the lack of pathology within a knee with an accuracy of 93%. It also has high sensitivity for diagnosis of ACL and meniscal tears

Shoulder Instability impacts on the ability of military personnel to fulfil their operational role and maintain sporting competence. Magnetic Resonance Imaging (MRI) and Arthrogram (MRA) are increasingly available as diagnostic adjuncts. We analysed MR reports from personnel undergoing stabilisation, correlating clinical diagnosis with operative findings and reviewed the literature in order to recommend improvements. We report a retrospective, consecutive case note analysis of 106 personnel undergoing open anterior capsulolabral reconstruction (ACLR) by a single surgeon. Seventy patients had MR (48 MRA, 22 MRI). Commonly reported pathology included Hill Sachs Lesions (41%), Soft tissue (59%) and bony Bankart lesions (16%), capsular laxity (20 %), supraspinatus lesion (20%), ACJ disease (13%) and SLAP tear (12%). The sensitivity of MR for identification of labral lesions was 82% with a specificity of 86%. For bony glenoid lesions, sensitivity was 63% and specificity 94%. Disparity between report and operative findings occurred mainly in standard MRI. Patients with lesions unrelated to instability achieved a pain free functioning shoulder following stabilisation. 100% of patients referred for ACLR with clinical evidence of instability without MR had positive pre-operative and operative correlation with instability. In 5 cases, the original equivocal MRI was repeated by MRA due to clinical suspicion of instability. In all cases the repeat MRA correlated with pre-operative and operative findings of instability. In 5 cases with equivocal clinical findings, MRA provided confirmation of instability. Delay in referral due to scanning and follow up ranged from 0 – 15 weeks. The diagnosis of those instigating referral is accurate. Reporting of MR is open to variation and has cost implications. MRA performed by a radiologist with a musculoskeletal specialist interest is recommended on an individual basis only and routine use of non-arthrographic studies should be discontinued. This will improve the efficiency of the fast track pathway

Shoulder Instability impacts on the ability of military personnel to fulfil their operational role and maintain sporting competence. Magnetic Resonance Imaging (MRI) and Arthrogram (MRA) are increasingly available as diagnostic adjuncts. We analysed MR reports from personnel undergoing stabilisation, correlating clinical diagnosis with operative findings and reviewed the literature in order to recommend improvements. This was a retrospective, consecutive case note analysis of 106 personnel undergoing open anterior capsulolabral reconstruction (ACLR) by a single surgeon. 70 patients had MR (48 MRA, 22 MRI). Commonly reported pathology included Hill Sachs Lesions (41%), Soft tissue (59%) and bony Bankart lesions (16%), capsular laxity (20 %), supraspinatus lesion (20%), ACJ disease (13%) and SLAP tear (12%). The sensitivity of MR for identification of labral lesions was 82% with a specificity of 86%. For bony glenoid lesions, sensitivity was 63% and specificity 94%. Disparity between report and operative findings occurred mainly in standard MRI. Patients with lesions unrelated to instability achieved a pain free functioning shoulder following stabilisation. 100% of patients referred for ACLR with clinical evidence of instability without MR had positive pre-operative and operative correlation with instability. In 5 cases, the original equivocal MRI was repeated by MRA due to clinical suspicion of instability. In all cases the repeat MRA correlated with pre-operative and operative findings of instability. In 5 cases with equivocal clinical findings, MRA provided confirmation of instability. Delay in referral due to scanning and follow up ranged from 0–15 weeks. The diagnosis of those instigating referral is accurate. Reporting of MR is open to variation and has cost implications. MRA performed by a radiologist with a musculoskeletal specialist interest is recommended on an individual basis only and routine use of non-arthrographic studies should be discontinued. This will improve the efficiency of the fast track pathway

Abstract. Objectives. Investigate Magnetic Resonance Imaging (MRI) as an alternative to Computerised Tomography (CT) when calculating kinematics using Biplane Video X-ray (BVX) by quantifying the accuracy of a combined MRI-BVX methodology by comparing with results from a gold-standard bead-based method. Methods. Written informed consent was given by one participant who had four tantalum beads implanted into their distal femur and proximal tibia from a previous study. Three-dimensional (3D) models of the femur and tibia were segmented (Simpleware Scan IP, Synopsis) from an MRI scan (Magnetom 3T Prisma, Siemens). Anatomical Coordinate Systems (ACS) were applied to the bone models using automated algorithms. 1. The beads were segmented from a previous CT and co-registered with the MRI bone models to calculate their positions. BVX (60 FPS, 1.25 ms pulse width) was recorded whilst the participant performed a lunge. The beads were tracked, and the ACS position of the femur and tibia were calculated at each frame (DSX Suite, C-Motion Inc.). The beads were digitally removed from the X-rays (MATLAB, MathWorks) allowing for blinded image-registration of the MRI models to the radiographs. The mean difference and standard deviation (STD) between bead-generated and image-registered bone poses were calculated for all degrees of freedom (DOF) for both bones. Using the principles defined by Grood and Suntay. 2. , 6 DOF kinematics of the tibiofemoral joint were calculated (MATLAB, MathWorks). The mean difference and STD between these two sets of kinematics were calculated. Results. The absolute mean femur and tibia ACS position differences (Table 1) between the bead and image-registered poses were found to be within 0.75mm for XYZ, with all STD within ±0.5mm. Mean rotation differences for both bones were found to be within 0.2º for XYZ (Table 1). The absolute mean tibiofemoral joint translations (Table 1) were found to be within ±0.7mm for all DOF, with the smallest absolute mean in compression-distraction. The absolute mean tibiofemoral rotations were found to be within 0.25º for all DOF (Table 1), with the smallest mean was found in abduction-adduction. The largest mean and STD were found in internal-external rotation due to the angle of the X-rays relative to the joint movement, increasing the difficulty of manual image registration in that plane. Conclusion. The combined MRI-BVX method produced bone pose and tibiofemoral kinematics accuracy similar to previous CT results. 3. This allows for confidence in future results, especially in clinical applications where high accuracy is needed to understand the effects of disease and the efficacy of surgical interventions. Acknowledgements: This research was supported by the Engineering and Physical Sciences Research Council (EPSRC) doctoral training grant (EP/T517951/1). Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Dupuytrens disease is a fibrosing condition of the palmar aponeurosis and its extensions within the digits. Normal fascial fibres running longitudinally in the subcutaneous tissues of the palm become thickened and form the characteristic nodules and cords pathognomonic of Dupuytrens disease. A wide variety of surgical interventions exist, of these the partial fasciectomy remains the most conventional and widely used technique. Minimally invasive surgical treatments such as needle fasciotomy are, however, becoming increasingly popular. Dupuytrens disease remains a challenging condition to treat as recurrence is universally found with all surgical interventions. Although recurrence may be related to the severity of the disease, there are currently no research tools other than clinical examination to examine changes in the diseased tissue postoperatively and predict likelihood of long-term success. Magnetic Resonance Imaging (MRI) may be of value for the study of Dupuytren disease, at present its use has been greatly underexplored. We wished to carry out a pilot study in order to examine the possibility of using 3.0 Tesla MRI to study Dupuytren tissue and then furthermore to examine the potential changes post-operatively following percutaneous fasciotomy. Five patients set to undergo percutaneous needle fasciotomy were recruited and consented for the study. All patients underwent MRI scanning of the affected hand pre-operatively and at two weeks post-operatively. Scanning was carried out in the 3.0 Tesla research MRI scanner at Aberdeen Royal Infirmary. Patients were placed prone in the MRI scanner with the hand outstretched above the head in the so-called “Superman” position. A specially designed wrist and hand coil was used. Under the expertise of radiographers and physicists, image capture encompassed four novel scanning sequences in order to make a volumetric three-dimensional image sample of the affected hand. MIPAV software (Bethesda, Maryland) was used for image analysis. Scanning revealed well defined anatomy. The Dupuytren cord arose from the palmar aponeurosis tissue which is deep to the palmar skin and subcutaneous tissue. It was distinctly different to deep structures such as the flexor tendons and intrinsic hand muscles which appeared with a uniform low and high signal respectively. The Dupuytren tissue had a heterogeneous signal on both T1 and T2 images. On T1 the tissue signal appeared high to intermediate, similar to that of bone and muscle, but low areas of signal were observed diffusely in an irregular fashion throughout. On T2 the tissue had a low signal throughout with some focal areas of high signal. Dupuytren tissue was mapped using MIPAV software for pre- and post-operative comparisons. Signal intensity, surface area and volume of the cords and fasciotomy sites were explored. Our initial results suggest MRI can be used to study Dupuytren tissue. Such a research tool may be of use to study the natural history of Dupuytren disease and furthermore, the response to medical and surgical interventions

Aim. The aim of this study was to compare the diagnostic accuracy of the Magnetic Resonance Imaging with that of Stress views of the ankle in testing the integrity of the lateral ankle ligaments. Arthroscopic diagnosis was used as the gold standard. Methods. This was a prospective study involving 45 patients who had previous trauma to the ankle and reported symptoms of ankle instability. Our patients were recreational athletes or military patients. These patients had MRI evaluation prior to arthroscopic evaluation and treatment of the ankle. The diagnosis regarding the integrity of the Calcaneofibular ligament (CFL) and the Anterior Talo-fibular ligament (ATFL), as obtained from the MRI was compared against the assessment of integrity from the stress views. These were compared against the assessment made by direct visualisation of the ligaments during arthroscopy. The sensitivity, specificity, negative (NPV) and positive predictive values (PPV) and accuracy were then calculated. Results. The sensitivity and specificity of the MRI and the stress views were poor for diagnosis of ATFL tears. However, the stress views had better sensitivity (93.7%) and specificity (96.5%), for the CFL, as compared with those of the Magnetic Resonance scans (sensitivity 50% and specificity of 86.2%). There was a difference between the diagnostic accuracy of the two methods of investigation with respect to integrity of the CFL but not of that of the ATFL. The PPV and the NPV for the ATFL was comparable using the MRI and the stress radiographs, the stress radiographs had a better predictive values for the calcaneo-fibular ligament, PPV of 93.7% and NPV of 96.5%. Conclusion. The results of this study suggest that routine pre-operative Magnetic Resonance Imaging is not beneficial or cost effective in diagnosing lateral ligament

Introduction: Whilst conventional Magnetic Resonance Imaging (MRI) is universally used as the method of choice for examining the boundaries of the intervertebral disc clinically it gives little information about the internal structure of the disc. This is largely due to the fact that the normal resolution of such devices (typically 1mm in plane and 3mm out of plane) is just too large to resolve structures and pathologies of interest. Aim: This work aims to describe the appearance of normal and pathological discs when imaged using a high resolution system. It then tests the hypothesis that a degeneration grading scale based upon such observations corresponds well with the graded appearance of the sectioned disc. Method: 13 lumbar discs from 7 non-chondrodystrophoid dogs (age 2–10 yr, mean 5.7 yr) were employed in this study. They were imaged using a small bore 0.5T research imaging system using a T2* weighted pulse sequence (TR=500ms, TE=17ms), a 60mm field of view, 1 mm slice thickness, in plane resolution was 230 μm. A grading scale based on the standard visual scale was developed for grading these images. Results: The outer and middle annulus had a strongly banded appearance with adjacent lamellae having high and low intensities (in spite of there similar chemical composition). The inner annulus (and frequently all the posterior annulus) had a uniform high intensity appearance as did the nucleus. Frequently, there has a well defined dark boundary between the annulus and nucleus. Increasing degeneration lead to disorder of the annulus structure and non-uniformity in the nucleus. Statistical comparison of the visual and MRI grading scales were extremely good (α=0.90–0.95) except for the posterior annulus (α=0.26). Conclusion: Many features of the MRI appearance of discs at high resolution, such as the banded structure of the annulus, were not expected and must be due to some subtle physical processes. Care must therefore be taken with the interpretation of such images, in particular to assessment of hydration. Grading of high resolution images corresponded well to the ‘gold standard’ of visual appearance on sectioning. However, this scale is totally different to that used to grade discs using conventional clinical MRI

Introduction and Aims: Ganglia are commonly seen during investigation of patients with wrist pain. Our aim was to determine the prevalence of ganglia in an asymptomatic population. Method: Following Institutional Ethical approval, Magnetic Resonance Imaging (MRI) was performed on the wrists of 103 asymptomatic volunteers. There were 67 males and 37 females, with an average age of 36, range 19–67 years. There were 52 right wrists and 51 left wrists. Using a 1.89 Tesla surface coil Magnetic Resonance Imager the following sequences were obtained: Coronal T 1, Proton Density, T 2 and Inversion Recovery sequences; Sagittal Inversion Recovery sequences; Axial T 1 and Inversion Recovery Sequences. The images were then evaluated independently by two Muskuloskeletal Radiologists and one Orthopaedic Surgeon. Results: Wrist Ganglia were identified in 53 out of 103 wrists. Wrist Ganglia were more prevalent in females than males, 58% compared to 48% respectively. The average long axis measurement was 7.5 mm (range 2.7–22.2), the average short axis measurement was 3.2 mm (range 1.6–10.1). Seventy percent of the Ganglia were found to originate from the volar capsule in the region of the interval between the Radio-Scapho-Capitate Ligament and the Long Radio-Lunate Ligament. Fourteen percent of the ganglia were dorsal and originated from the dorsal, distal fibres of the Scapho-Lunate Ligament. Two ganglia had surrounding soft tissue oedema and one had an associated intra-osseous component. Conclusion: The prevalence of asymptomatic wrist ganglia is high – 51%. Unlike previous surgical and pathological series, our study showed volar wrist ganglia are more common than dorsal wrist ganglia in the asymptomatic population. The vast majority of these asymptomatic ganglia do not show associated ligamentous disruption, soft tissue oedema or intra-osseous communication

Study Design: A retrospective analysis of patients with spinal disorders using Magnetic Resonance Imaging (MRI) results. Objective: To review the clinical and MRI results of patients with various scoliotic deformities. Background: Insufficient reports exist regarding the MRI’s of scoliotic deformities. MRI’s can offer vital information in the diagnosis of various types of scoliosis and their concomitant disorders. Methods: MRI reults of a total of 277 patients with various types of scoliosis/kyphoscoliosis were reviewed. All patients met the cobb angle criteria: > or = 20 degrees. 65 (23.46%) patients were male and 212 (76.53%) were female. 224 (80.86%) patients received conservative treatment and 53 (19.14%) underwent surgical treatments. 107 (38.62%) patients had adolescent idiopathic scoliosis, mean age: 13.7 (7–18) years, 76 (27.43%) adult idiopathic, mean age: 29.53 (19–79) years, 48 (17.32%) congenital, mean age: 12.6, (1–46) years, 29 (10.46%) neuromuscular, mean age: 12.86 (2–30) years, 15 (5.41%) syndromic, mean age: 13.6 (1–29) years, 2 (0.72%) tumor related, mean age:10.5 (8–13) years. Results: MRI results revealed the spinal cord of 169 (61.01%) patients as normal: no spinal cord anomalies, tumors, or congenital problems. Of the remaining patients 108 (38.98%) the following irregularities were diagnosed: 39 (36.11%) syringohydromyeli in various spinal locations, 29 (26.85%) butterfly vertebrae, 19 tethered cord (17.59%), 10 (9.2%) split cord, 10 diastometamyelia, 10 cleft vertebrae, 14 (12.96%) myelomeningocele, 7 (6.48%) grade one spondilolisthezis, 5 (4.62%) caudal regression syndromes, 6 (5.55%) vertebra partial fusion, 4 (3.7%) cranio-cervical problems, 4 cerebellar tonsillar ectopia, 3 (2.77%) block vertebra, 3 chiari typ2 II, 3 TIS, 2 (1.85%) tumors on the spinal column, 2 neurofibromatosis, 2 introdural lipoma, 2 myelomalacia of the spinal cord, 2 spinal cord injuries, 1 (0.92%) arachnoid cyst, 1 neuroanteric, 1 spina bifida, 1 scheuermann, 1 vertebral artery hypoplasia, 1 sacral dermal sinus, 1 cervical rib, 1 interpedicullar cyst, 1 high scapula, 1 sphenoid sinus retention cyst, 1 paravertebral cyst, 1 Schmorl’s node, 1 Tarlow cyst and 1 intercranial pineal cyst. Conclusion: Our study revealed how MRI analysis can lead to the accurate diagnosis of scoliotic deformities. In many cases tumors, neuromuscular pathology and syndromic conditions can be misdiagnosed as scoliotic. Careful MRI review can offer vital information for diagnosis and help determine the classification of scoliosis and subsequent treatment

We evaluated the accuracy of a Magnetic Resonance Imaging (MRI)-based method to measure three-dimensional patellar tracking during loaded knee flexion. This method determines the relative positions of the knee bones by shape matching high-resolution three-dimensional geometric models of these bones to fast low-resolution scans taken during loaded flexion. The accuracy of the method’s assessment of patellar position and orientation was determined by comparing test measurements in four cadaver specimens to measurements made in the same specimens using Roentgen Stereophotogrammetric Analysis (RSA). This MRI-based method is more accurate than current two-dimensional imaging methods. The purpose of this study was to determine the accuracy of a MRI-based technique for measuring patellar tracking in loaded flexion. This novel, noninvasive, MRI-based method measures three-dimensional patellar tracking during loaded knee flexion with sufficient accuracy to detect clinically significant changes. Although abnormal patellar tracking is widely believed to be associated with pain and cartilage degeneration at the patella, these relationships have not been clearly established because most current methods assess only the two-dimensional alignment of the patella at one position. Measurements possible with this method should be sufficiently accurate to yield new insights into these relationships. Four cadaver knee specimens were flexed through seventy-five degrees of flexion in an MRI-compatible knee loading rig. A high-resolution image was acquired with each knee in extension and then a series of low-resolution scans (in two slice directions: axial and sagittal) were acquired through a flexion cycle. Segmenting bone outlines from high-resolution scans generated models of the femur, tibia and patella. These models were shape matched to the segmented bone outlines in the low resolution scans. Patellar attitude and position were determined and compared to measurements made using RSA. The mean measurement error in every kinematic parameter was lower for “fast” sagittal plane slices than for “fast” axial plane slices. In general, the mean measurement error was increased by decreasing the number of low-resolution slices. This method is more accurate than many two-dimensional methods, exposes participants to no ionizing radiation, and can be used through a large range of loaded knee flexion. Funding: Supported by an operating grant from the Canadian Institutes for Health Research and a Strategic Grant from the Natural Sciences and Engineering Research Council. NJM is supported by the Arthritis Society/CIHR Partnership Fund. Please contact author for figures and/or tables

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

Introduction: Evaluation of the hip joint space was performed in patients with Legg-Calve-Perthes disease in this study. Materials and Methods: Seventy-eight patients (85 affected hips and 71 unaffected hips) with LCP disease were reviewed respectively to evaluate widening of the hip joint space, the extent of epiphyseal subchondral fracture, and metaphyseal changes. The mean age of the patients was 7.4 years (range, 3–13 years). There were 27 hips at the initial stage, 23 at the fragmentation stage, and 11 at the healing stage. The metaphyseal changes in MRI scans were classified as no change, marrow edema, false cyst, and true cyst. The false cyst was defined as a cyst located at the epiphysis, physis, and metaphysis. The true cyst was defined as a cyst located within the metaphysis. Results:The widened medial joint space at the initial stage was filled with overgrown cartilage of the femoral head and acetabulum on Magnetic Resonance Imaging (MRI) and radiographs. At the fragmentation stage, there was both overgrown cartilage and markedly widened true medial joint space, which was filled with an amount of joint fluid and hypertrophied synovial tissue. Widening of the true medial joint space at the initial stage had no correlation with lateral subluxation, whereas there was a definite correlation at the fragmentation stage. In the healing stage, coxa magna contributed to lateral subluxation rather than the widening of the false medial joint space, because it had decreased or normalized because of ossification of this overgrown cartilage and normalization of the synovial hypertrophy. The overall proportion of agreement was conducted by two groups of observers according to different classification systems. The results for Catterall groups 2, 3, and 4 showed 70% agreement with the Salter-Thompson classification, 65% with the MRI classification, and 75% in the Catterall classification. The subchondral fracture line had a prognostic significance in 17 of 20 hips (85%). The MRI had a prognostic significance in 10 of 20 hips (50%). Among 85 hips, there were no changes in 32 hips, marrow edema in 13 hips, false cysts in 28 hips, and true cysts in 12 hips. Discussion: The hips without metaphyseal change had less involvement of the epiphysis compared to the hips with the metaphyseal change. Metaphyseal cysts disappeared on radiographs and MRI scans during the healing or remodeling stage

Introduction: The use of an ejection seat to escape from a stricken aircraft is associated with the exposure of significant forces. These vertical accelerative forces on the body are in the order of 15–25G with rates of onset of up to 250G per second. Therefore, it is common to see vertical compression fractures, mainly in the thoracolumbar region. Although most vertebral fractures are evident on plain radiographs, subtle spinal injuries elsewhere may not be immediately apparent. Aim: A prospective study to evaluate for the presence of occult spinal injuries using MRI following aircraft ejection. Methods: Between 1996 and 2003, 22 ejectees from 18 aircrafts, mean age 32 years (range 24 to 48), were admitted to a regional spinal unit for comprehensive evaluation of their injuries that included whole spine radiographs and Magnetic Resonance Imaging (T1, T2 weighted and STIR sagittal sequences). All ejections occurred within the ejection envelope and were flying below 2000 ft (mean 460 feet) and below 500 knots airspeed (mean 275 knots). Results: All 5 ejectees (23%) with vertebral compression fractures, one at T6 and 4 in thoracolumbar region, had pain and tenderness in the appropriate area of the spine that was evidently detected on plain radiographs. 3 of these patients with a thoracolumbar fracture (AO A3.3) had more than 50% canal compromise and more than 30 degrees angular kyphosis underwent surgery. Neurological compromise consisting of acute cauda equina syndrome occurred in one patient with a L2 AO A3.3 fracture. More importantly 10 ejectees (45%) had MRI evidence totalling 21 occult thoracic and lumbar vertebral fractures. 4 ejectees had a single occult fracture, 4 had double, 1 had 3 and 1 had 6 occult fractures. Conclusion: This study confirms the high incidence of occult vertebral injuries following vertical acceleration insult to the spine consequent to emergency aircraft ejection. Once life-saving priority measures have taken place MRI of the entire spine remains mandatory as part the comprehensive evaluation of the patient. Early use of MRI scanning in the management will significantly increase an ejectee’s safe return to flying duties

Study Design: Retrospective review. Objective: A prospective study to evaluate for the presence of occult spinal injuries using MRI following aircraft ejection. Summary of Background Data: The use of an ejection seat in order to escape from a stricken aircraft is associated with the exposure of significant forces. These vertical accelerative forces on the body are in the order of 15 – 25G with rates of onset of up to 250G per second. Therefore, it is common to see vertical compression fractures, mainly in the thoraco-lumbar region. Although most vertebral fractures are evident on plain radiographs, other subtle spinal injuries elsewhere may not be immediately apparent. Methods: Between 1996 and 2003, 22 ejectees from 18 aircrafts, mean age 32 years (range 24 to 48), were admitted to a regional spinal unit for comprehensive evaluation of their injuries that included whole spine radiographs and Magnetic Resonance Imaging (T1, T2 weighted and STIR sagittal sequences). All ejections occurred within the ejection envelope and were flying below 2000 ft (mean 460 feet) and below 500 knots airspeed (mean 275 knots). Results: All 5 ejectees (23%) with vertebral compression fractures (one at T6 and 4 in thoraco-lumbar region) had pain and tenderness in the appropriate area of the spine that was evidently detected on plain radiographs. 3 of these patients with a thoraco-lumbar fracture (AO A3.3) had more than 50% canal compromise and more than 30 degrees angular kyphosis underwent surgery. Neurological compromise consisting of acute cauda equine syndrome occurred in one patient with a L2 AO A3.3 fracture. More importantly 10 ejectees (45%) had MRI evidence totalling 21 occult thoracic and lumbar vertebral fractures. 4 ejectees had a single occult fracture, 4 had double, 1 had 3 and 1 had 6 occult fractures. Conclusion: This study confirms the high incidence of occult vertebral injuries following vertical acceleration insult to the spine consequent to emergency aircraft ejection. Once life-saving priority measures have taken place, MRI of the entire spine remains mandatory as part the comprehensive evaluation of the patient. Early use of MRI scanning in the management will significantly increase an ejectee’s safe return to flying duties

Introduction

Anterior shoulder instability results in labral and osseous glenoid injuries. With a large osseous defect, there is a risk of recurrent dislocation of the joint, and therefore the patient must undergo surgical correction. An MRI evaluation of the patient helps to assess the soft tissue injury. Currently, the volumetric three-dimensional (3D) reconstructed CT image is the standard for measuring glenoid bone loss and the glenoid index. However, it has the disadvantage of exposing the patient to radiation and additional expenses. This study aims to compare the values of the glenoid index using MRI and CT.

Abstract

MRI has been little utilised in the post-operative assessment of joint replacement due to the problem of artifact. With modern machines and sequencing, artifact can be minimised in small joints with titanium prostheses. Twenty four consecutive patients implanted with a Buechel-Pappas Total Ankle Replacement underwent MRI examination at an average of 583 days post surgery to determine its usefulness as an adjunct to x-ray and bone scan in assessing prosthetic integrity and the source of post-operative symptoms.

The purpose of the study was to evaluate the use of modified MRI techniques in the assessment of bone-implant interface, soft tissue changes, bone oedema and extent of osteolysis in setting of total ankle joint replacement and propose a descriptive classification to document the changes.

We found MRI was extremely useful in identifying abnormalities in structures apart from the prosthesis such as occult degeneration in the subtalar joint and ligament pathology. Despite the new techniques, artifact remains a problem when assessing the bone prosthesis interface although adjacent bone oedema is well seen.

MRI has a role in the identification of pathology in the tissues surrounding a TAJR especially with unexplained pain in an otherwise well functioning prosthesis. It's role in the assessment of prosthetic integrity remains qualitative but further work will be required to correlate MRI findings with clinical examination.

Background

The anatomy of the human body has been studied for centuries. Despite this, recent articles have announced the presence of a new knee ligament- the anterolateral ligament. It has been the subject of much discussion and media commentary. Previous anatomical studies indicate its presence, and describe its location, origin, course and insertion. Magnetic resonance imaging (MRI) is the best and most commonly used investigation to assess the ligamentous structure of the knee. To date, most MRI knee reports make no mention of the anterolateral ligament. The aim of this study was to assess for the presence of the anterolateral ligament using MRI, and to describe the structure if visualised.

Aims and objectives

Our aim was to evaluate the indications for patients undergoing magnetic resonance imaging (MRI) of the knee prior to referral to an orthopaedic specialist, and ascertain whether these scans altered initial management.

Background

MRI is the preferred modality for the diagnosis of ankle joint pathology. Musculoskeletal radiologists aim to determine and report both chondral and/or osseous stability/instability of each lesion. The aim of this study was to specifically analyse the reliability of MRI reported findings in predicting the stability of OCL's in symptomatic patients.