The clinical diagnosis of distal radioulnar joint (DRUJ) instability remains challenging. The current diagnostic gold standard is a dynamic computerized topography (CT) scan. This investigation compares the affected and normal wrists in multiple static positions of forearm rotation.. However, its accuracy has been questioned, as the wrist is unloaded and not placed under stress. This may fail to capture DRUJ instability that does not result in static malalignment between the ulnar head and sigmoid notch. The purpose of this biomechanical study was to evaluate the effectiveness of both dynamic and stress CT scans in detecting DRUJ instability. A customized DRUJ arthrometer was designed that allows for both static positioning, as well as dorsal and volar loading at the DRUJ in various degrees of forearm rotation. Ten fresh frozen cadavers were prepared and mounted in the apparatus. CT scans were performed both in the unloaded condition (dynamic CT) and with each arm subjected to a standardized 50N volar and dorsal force (stress CT) in neutral and maximum pronation/ supination. The TFCC (triangular fibrocartilage complex)was then sectioned peripherally to simulate DRUJ instability and the methodology was repeated. CT scans were then evaluated for displacement using the radioulnar ratio method. When calculating the radioulnar ratio for intact wrists using the dynamic CT technique, values were 0.50, 0.64, 0.34 for neutral, pronation and supination, respectively. When the TFCC was sectioned and protocol repeated, the values for the simulated unstable wrist for dynamic CT were 0.54, 0.62, 0.34 for neutral, pronation and supination, respectively. There was no statistically significant difference between the intact and sectioned states for any position of forearm rotation using dynamic CT. Usingstress CT, mean radioulnar ratios for the intact specimens were calculated to be 0.44, 0.36 and 0.31 for neutral, pronation and supination, respectively. After sectioning the TFCC, the radioulnar ratios increased to 0.61, 0.39 and 0.46 for neutral, pronation and supination. There was a statistically significant difference between intact and simulated-unstable wrists in supination (p = 0.002) and in neutral (p=0.003). The radioulnar ratio values used to measure DRUJ translation for dynamic CT scans were unable to detect a statistically significant difference between stable and simulated unstable wrists. This was true for all positions of forearm rotation. However, when a standard load was placed across the DRUJ, statically significant changes in the radioulnar ratio were seen in neutral and supination between stable and simulated unstable wrists. This discrepancy challenges the current gold standard of dynamic CT in its ability to accurately diagnosis DRUJ instability. It also introduces stress CT as a possible solution for diagnosing DRUJ instability from peripheral TFCC lesions

The emergence of patient specific instrumentation has seen an expansion from simple radiographs to plan total knee arthroplasty (TKA) with modern systems using computed tomography (CT) or magnetic resonance imaging scans. Concerns have emerged regarding accuracy of these non-weight bearing modalities to assess true mechanical axis. The aim of our study was to compare coronal alignment on full length standing AP imaging generated by the EOS acquisition system with the CT coronal scout image. Eligible patients underwent unilateral or bilateral primary TKA for osteoarthritis under the care of investigating surgeon between 2017 and 2022, with both EOS X-Ray Imaging Acquisition System and CT scans performed preoperatively. Coronal mechanical alignment was measured on the supine coronal scout CT scan and the standing HKA EOS. Pre-operative lower limb coronal alignment was assessed on 96 knees prior to TKA on the supine coronal scout CT scan and the standing HKA EOS. There were 56 males (56%), and 44 right knees (44%). The mean age was 68 years (range 53-90). The mean coronal alignment was 4.7 degrees (SD 5.3) on CT scan and 4.6 degrees (SD 6.2) on EOS (p=0.70). There was a strong positive correlation of coronal alignment on CT scan and EOS (pearson. 0.927, p=0.001). The mean difference between EOS and CT scan was 0.9 degrees (SD 2.4). Less than 3 degrees variation between measures was observed in 87% of knees. On linear regression for every 1° varus increase in CT HKA alignment, the EOS HKA alignment increased by 0.93° in varus orientation. The model explained 86% of the variability. CT demonstrates excellent reliability for assessing coronal lower limb alignment compared to EOS in osteoarthritic knees. This supports the routine use of CT to plan TKA without further weight bearing imaging in routine cases

Aims. The aim of this study was to assess the reproducibility and validity of cross table radiographs for measuring the anteversion of the acetabular component after total hip arthroplasty (THA) and to compare it with measurements using CT scans. Patients and Methods. A total of 29 patients who underwent THA between June 2010 and January 2016 were included. There were 17 men and 12 women. Their mean age was 43 years (26 to 65). Seven patients underwent a bilateral procedure. Thus, 36 THAs were included in the study. Lateral radiographs and CT scans were obtained post-operatively and radiographs repeated three weeks later. The anteversion of the acetabular component was measured using the method described by Woo and Morrey and the ischiolateral method described by Pulos et al and these were compared with the results obtained from CT scans. Results. The mean anteversion was 18.35° (3° to 38°) using Woo and Morrey’s method, 51.45° (30° to 85°) using the ischiolateral method and 21.22° (2° to 48°) using CT scans. The Pearson correlation coefficient was 0.754 for Woo and Morrey’s method and 0.925 for the ischiolateral method. There was a linear correlation between the measurements using the ischiolateral method and those using CT scans. We derived a simple linear equation between the value of the CT scan and that of ischiolateral method to deduce the CT scan value from that of ischiolateral method and vice versa. . Conclusion. The anteversion of the acetabular component measured using both plain radiographic methods was consistently valid with good interobserver reproducibility, but the ischiolateral method which is independent of pelvic tilt was more accurate. As CT is costly, associated with a high dose of radiation and not readily available, the ischiolateral method can be used for assessing the anteversion of the acetabular component. Cite this article: Bone Joint J 2017;99-B:1006–11

Aims. We quantitatively compared the 3D bone density distributions on CT scans performed on scaphoid waist fractures subacutely that went on to union or nonunion, and assessed whether 2D CT evaluations correlate with 3D bone density evaluations. Methods. We constructed 3D models from 17 scaphoid waist fracture CTs performed between four to 18 weeks after fracture that did not unite (nonunion group), 17 age-matched scaphoid waist fracture CTs that healed (union group), and 17 age-matched control CTs without injury (control group). We measured the 3D bone density for the distal and proximal fragments relative to the triquetrum bone density and compared findings among the three groups. We then performed bone density measurements using 2D CT and evaluated the correlation with 3D bone densities. We identified the optimal cutoff with diagnostic values of the 2D method to predict nonunion with receiver operating characteristic (ROC) curves. Results. In the nonunion group, both the distal (100.2%) and proximal (126.6%) fragments had a significantly higher bone density compared to the union (distal: 85.7%; proximal: 108.3%) or control groups (distal: 91.6%; proximal: 109.1%) using the 3D bone density measurement, which were statistically significant for all comparisons. 2D measurements were highly correlated to 3D bone density measurements (Spearman’s correlation coefficient (R) = 0.85 to 0.95). Using 2D measurements, ROC curve analysis revealed the optimal cutoffs of 90.8% and 116.3% for distal and proximal fragments. This led to a sensitivity of 1.00 if either cutoff is met and a specificity of 0.82 when both cutoffs are met. Conclusion. Using 3D modelling software, nonunions were found to exhibit bone density increases in both the distal and proximal fragments in CTs performed between four to 18 weeks after fracture during the course of treatment. 2D bone density measurements using standard CT scans correlate well with 3D models. In patients with scaphoid fractures, CT bone density measurements may be useful in predicting the likelihood of nonunion. Cite this article: Bone Joint J 2020;102-B(9):1200–1209

Aim: 1. To assess the role of the CT scan in management of intra-articular fractures of the calcaneum. 2. Does the scan makes any difference to the management decision, obtained from assessing the plain radiograph?. Methodology: This study involved 24 patients with intra-articular fracture of the calcaneum who had both a plain radiograph and a CT scan as a part of their assessment. Three consultants who were blinded to the actual management and names of the subjects were independently asked to grade the radiographs and CT scans, as operative or non-operative, on different occasions. The data was matched to the actual management and was subjected to statistical analysis. Results: The data was non-parametric and related. The SIGN test was used to analyse the agreement between the three observers and if the decisions made in each of the groups were significantly different from the actual management. There was no statistically significant difference, between the management decision from the radiographs or CT and the actual management. The change in management that the CT scan brought about was also assessed for each of the observers using the McNemars test. The CT scan did not make any significant difference to the decision made based on the plain radiographs, on whether to operate or not. A Cochran Q test used to assess the variability of the decisions, showed that there was more inter-observer variability in decision making, using the CT based assessment (Q=9.50, p=0.009) as compared to plain radiographs (Q=3.84, p=0.14). Conclusion: We conclude that, the CT scan should only be requested when a decision is made to operate on the fracture, based on plain radiographs. This may help with pre-operative planning of fracture fixation. It does not have to be obtained as a routine to assess all intra-articular fractures of the calcaneum

Aims. Malreduction of the syndesmosis has been reported in up to 52% of patients after fixation of ankle fractures. Multiple radiological parameters are used to define malreduction; there has been limited investigation of the accuracy of these measurements in differentiating malreduction from inherent anatomical asymmetry. The purpose of this study was to identify the prevalence of positive malreduction standards within the syndesmosis of native, uninjured ankles. Methods. Three observers reviewed 213 bilateral lower limb CT scans of uninjured ankles. Multiple measurements were recorded on the axial CT 1 cm above the plafond: anterior syndesmotic distance; posterior syndesmotic distance; central syndesmotic distance; fibular rotation; and sagittal fibular translation. Previously studied malreduction standards were evaluated on bilateral CT, including differences in: anterior, central and posterior syndesmotic distance; mean syndesmotic distance; fibular rotation; sagittal translational distance; and syndesmotic area. Unilateral CT was used to compare the anterior to posterior syndesmotic distances. Results. A difference of anterior to posterior syndesmotic distance > 2 mm was observed in 89% of ankles (n = 190) on unilateral CT assessment. Using bilateral CT, we found that 35% (n = 75) of normal ankles would be considered malreduced by current malreduction parameters. In 50 patients (23%), only one parameter was anomalous, 18 patients (8%) had two positive parameters and seven patients (3%) had three. Difference in fibular rotation had the lowest false positive rate of all parameters at 6%, whereas posterior syndesmotic distance difference had the highest at 15%. Conclusion. In this study, 35% of native, uninjured syndesmoses (n = 75) would be classified as malreduced by current diagnostic standards on bilateral CT and 89% had an asymmetric incisura on unilateral CT (n = 190). Current radiological parameters are insufficient to differentiate mild inherent anatomical asymmetry from malreduction of the syndesmosis. Cite this article: Bone Joint J 2021;103-B(1):178–183

The aim of this study was first, to determine whether CT scans undertaken to identify serious injury to the viscera were of use in detecting clinically unrecognised fractures of the thoracolumbar vertebrae, and second, to identify patients at risk of ‘missed injury’. . We retrospectively analysed CT scans of the chest and abdomen performed for blunt injury to the torso in 303 patients. These proved to be positive for thoracic and intra-abdominal injuries in only 2% and 1.3% of cases, respectively. However, 51 (16.8%) showed a fracture of the thoracolumbar vertebrae and these constituted our subset for study. There were eight women and 43 men with mean age of 45.2 years (15 to 94). There were 29 (57%) stable and 22 (43%) unstable fractures. Only 17 fractures (33.3%) had been anticipated after clinical examination. Of the 22 unstable fractures, 11 (50%) were anticipated. Thus, within the whole group of 303 patients, an unstable spinal injury was missed in 11 patients (3.6%); no harm resulted as they were all protected until the spine had been cleared. A subset analysis revealed that patients with a high Injury Severity Score, a low Glasgow Coma Scale and haemodynamic instability were most likely to have a significant fracture in the absence of positive clinical findings. This is the group at greatest risk. Clinical examination alone cannot detect significant fractures of the thoracolumbar spine. It should be combined with CT imaging to reduce the risk of missed injury

Aim: The aim of the study was to investigate the efficacy of the multidetector CT scan in the diagnosis and classification of pelvic and acetabular fractures. Material and Method: 41 patients, 13 women and 28 men suspect for acetabular or pelvic fracture were examined. Patient’s ranged from 15 to 72 years. Fracture classification was based in that of Letournel and Judet. Examination was performed with a Multidetector CT scanner (Phillips-Brilliance), withnmultiple detectors and thin slices of 2 mm Multilevel and three dimensional reconstructions were performed. Results: in 15 patients suspects for pelvic or acetabular fracture in plain xray, the CT scan was negative for revealing a fracture. In the rest 26 patients, there were 19 fractures of the anterior column, 4 fractures of the posterior column, 11 acetabular fractures and 7 sacral fractures. All the fractures were detected at the horizontal plane. MPR views were offered additional information for the sacral and acetabular fractures. In 7 patients the fractures diagnosed only after the CT scan was performed. In these patient plain x-rays were negative for fracture. In 6 patients the treatment algorithm was modified, based on CT scans findings. Conclusion: We believe that MDCT is an appropriate as well as an essential method in patients suspects for pelvic or acetabular injuries. MPR and three dimensional reconstructions are very helpful in revealing the personality of the fracture element very important for classification purposes as well as for planning treatment

Distal tibial physeal fractures are the second most common growth plate injury and the most common cause of growth arrest and deformity. This study assesses the accuracy of pre-operative planning for placement of the screws in these fractures using either standard radiographs or CT scans. We studied 62 consecutive physeal fractures over a period of four years. An outline of a single cut of the CT scan was used for each patient. An ideal position for the screw was determined as being perpendicular to and at the midpoint of the fracture. The difference in entry point and direction of the screw between the ideal and the observers’ assessments were compared using the paired Student’s t-test. There was a statistically significant improvement (p < 0.0001) in the accuracy of the point of insertion and the direction of the screw on the pre-operative plan when CT scans were used rather than plain radiographs. We would, therefore, recommend that CT scans are routinely used in the pre-operative assessment and treatment of distal tibial physeal fractures

Aim: To assess the implications of implementation of the NICE Guidelines for indication for CT scan in head injury patients. Methods and Materials: A retrospective audit of the patients attending our district general hospital with head injuries over a period of one year from October 2004 till Sept 2005. A total of 3150 patients attending the A & E during the study period were diagnosed to have head injuries. The study involved review of the case notes and radiology results of the 135 patients requiring inpatient treatment for head injury. During this tenure the CT scan was requested depending of the clinical judgement of the attending physician. Results: Rigid compliance with the NICE Guidelines during the study tenure would have entailed an additional workload of 36 patients requiring a CT scan, of which 28 patients justified the scan during out of hours period. One elderly patient with a fatal intracerebral bleed was found to have justified an early CT scan on the criteria of more than one vomiting episode and a history of unconsiousness. Discussion: The NICE Guidelines were found to be implemented in most cases admitted during working hours. A reluctance to perform CT scan was encountered during out of hours. A strict compliance with the guidelines would entail on average one additional CT scan every fortnight during the ‘out of hours’ period. Implementation of NICE Guidelines was found to tighten the net (justify CT scan) in order not to miss subtle early signs of potentially fatal head injuries

Aims. To evaluate whether an ultra-low-dose CT protocol can diagnose selected limb fractures as well as conventional CT (C-CT). Patients and Methods. We prospectively studied 40 consecutive patients with a limb fracture in whom a CT scan was indicated. These were scanned using an ultra-low-dose CT Reduced Effective Dose Using Computed Tomography In Orthopaedic Injury (REDUCTION) protocol. Studies from 16 selected cases were compared with 16 C-CT scans matched for age, gender and type of fracture. Studies were assessed for diagnosis and image quality. Descriptive and reliability statistics were calculated. The total effective radiation dose for each scanned site was compared. Results. The mean estimated effective dose (ED) for the REDUCTION protocol was 0.03 milliSieverts (mSv) and 0.43 mSv (p < 0.005) for C-CT. The sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of the REDUCTION protocol to detect fractures were 0.98, 0.89, 0.98 and 0.89 respectively when two occult fractures were excluded. Inter- and intra-observer reliability for diagnosis using the REDUCTION protocol (κ = 0.75, κ = 0.71) were similar to those of C-CT (κ = 0.85, κ = 0.82). Using the REDUCTION protocol, 3D CT reconstructions were equivalent in quality and diagnostic information to those generated by C-CT (κ = 0.87, κ = 0.94). Conclusion. With a near 14-fold reduction in estimated ED compared with C-CT, the REDUCTION protocol reduces the amount of CT radiation substantially without significant diagnostic decay. It produces images that appear to be comparable with those of C-CT for evaluating fractures of the limbs. Cite this article: Bone Joint J 2016;98-B:1668-73

Aim: The purpose of this study is to define the hip anatomy in cerebral palsy in a three dimensional geometrical manner and then perhaps plan a better surgical reconstruction for these affected hips. Materials & Methods: The case notes and radiographs of 18 patients with cerebral palsy who underwent plain radiographs, axial CT and 3D CT scans from October 1993 to June 1995 were reviewed prospectively all being consecutive. The following indices were measured – acetabular anteversion (AA), anterior axial acetabular index (Anterior AAI), posterior axial acetabular index (Posterior AAI), Total axial acetabular index (Total AAI) and acetabular depth/femoral head diameter (AD/FHD) ratio. Results: The acetabular index, and CEA angle clearly showed the hips to be dysplastic in frontal plane. FAV measurements done on CT scan in our study was 330 on the right and 420 on the left. This was significantly higher than normal in our group of patients. Acetabular anteversion was higher in our series, which contributed to hip instability. There were no patients with acetabular retroversion. The axial acetabular indices suggested predominant anterior than posterior acetabular dysplasia, and the total AAI was suggestive of a flatter and shallower acetabulum. A normal to minimally increased AAI in our study suggests an increase in the size rather than a true malrotation. Conclusions: Our study shows that CT scan analysis is a useful tool in preoperative planning for hip reconstructions. This analysis gives a better idea of the distorted anatomy and a more accurate quantitative and qualitative assessment of the hips

Introduction:. 25% of patients with an unknown primary tumour present to the orthopaedic surgeon with skeletal metastases. The onus is on the orthopaedic surgeon to establish the diagnosis, not only to decrease the patient's anxiety but also because the median survival increases from 6–9 months to 23 months when the primary is identified and allows for specific cancer treatment. The diagnostic work up of an unknown primary includes a multitude of special investigations. Since PET/CT has high sensitivity and specificity for detecting the primary tumours, we asked the question: Can you diagnose the unknown primary in patients with skeletal metastases with a PET/CT?. Method:. We included all PET/CT scans done in our institution between 2010 and 2013 for patients with malignancies known to metastasize to bone (melanoma, breast, lung, head and neck, GIT, other) and all scans done in patients with unknown primaries. After reviewing 686 PET/CT scans, 492 showed metastatic disease, with 78 of these having either spinal or skeletal metastases. Results:. Of these 78 patients, 68 primaries could be detected on the PET/CT scan. Thus the PET/CT detected the primary in 87% of cases. This number could possibly be higher as some were melanoma and breast cancer patients who had already undergone surgical resection. The most common primary detected was lung, followed by a group of other and unknown primaries which included cervical, kidney and thyroid carcinoma. Conclusion:. PET/CT scan is a good modality to use when looking for a primary malignancy in patients who present to the orthopaedic surgeon with bone metastases. We postulate that this might be a possible first line investigation when looking for the primary

Computed tomography was performed on 40 patients with recent hip trauma. Radiographs of 25 showed a fracture of the femoral neck with slight displacement; 24 of these had intra-articular fluid and 20 had a lipohaemarthrosis on the CT scan. In 15 patients, radiographs at the time of admission were normal but suspicion of fracture remained. A fracture was later verified in five patients, four of whom had lipohaemarthrosis on admission. In the remaining 10 patients no fracture could be detected; only one patient had a hip joint effusion but no free fat. Thus all 24 patients with lipohaemarthrosis had an intracapsular fracture of the hip. We suggest CT for patients with hip trauma and negative radiographs. The presence of a lipohaemarthrosis of the hip strongly suggests an intra-articular fracture of either the femoral neck or the acetabulum

Aim: The aim of this study is to evaluate the efficacy of the multidetector CT scan in shoulder fractures and to correlate these findings with those of plain x-rays. Material and Method: A 105 patients with shoulder fracture were examined with a multidetector CT scanner after the acute injury. There were 64 male and 41 female with an average age of 52 yrs (range 16–95 yrs). The examination was performed with a CT PHILIPS BRILLIANCE, and six groups of detectors were used, with thin slices (1.6–2 mm). MPR and three dimensional reconstructions were performed. Results: The mechanism of injury was fall during walk in 66 patients, fall from a height in 11 patients, and road traffic accident in 28 patients. They were detected 210 fractures at the shoulder region. A 135 fractures were located at the proxd imal end of the humerus, 75 at the scapula, in 95 out of 105 patients. In 10 patients with a comminuted fracture of the upper end of the humerus, the exact number of fragments as well as the precise location of them was not accurately assessed with plain xrays. MDCT control with multilevel anasynthesis and three dimensional reconstruction improved the understanding of the anatomic orientation in complex fractures and fractures–dislocations and in detection of subluxation of the fragments of the shoulder headin four part fractures in two patients. Conclusion: Our results would orient us for using the MDCT scan in patients with acute shoulder injury, especially in cases with comminuted fractures, because it is better assessed the place, the orientation and the displacement of fragments, which are not easily identified in plain xrays. Furthermore, these reconstructions improve the preoperative planning in those patients

Mechanical irritation or impingement of the iliopsoas tendon accounts for 2–6% of persistent postoperative pain cases after total hip arthroplasty (THA). The most common trigger is anterior cup overhang. CT-scan can be used to identify and measure this overhang; however, no threshold exists for symptomatic anterior iliopsoas impingement. We conducted a case–control study in which CT-scan was used to define a threshold that differentiates patients with iliopsoas impingement from asymptomatic patients after THA. We analyzed the CT-scans of 622 patients (758 CT-scans) between 2011 and 2020. Out of this population we identified 136 patients with symptoms suggestive of iliopsoas impingement. Among them, 6 were subsequently excluded: three because the diagnosis was reestablished intra-operatively (one metallosis, two anterior instability related to posterior prosthetic impingement) and three because they had another obvious cause of impingement (one protruding screw, one protruding cement plug, one stem collar), leaving 130 patients in the study (impingement) group. They were matched to a control group of 138 patients who were asymptomatic after THA. The anterior cup overhang (anterior margin of cup not covered by anterior wall) was measured by an observer (without knowledge of the clinical status) on an axial CT slice based on anatomical landmarks (orthogonal to pelvic axis). The impingement group had a median overhang of 8 mm [IQR: 5 to 11] versus 0 mm [IQR: 0 to 4] for the control group (p<.001). Using ROC curves, an overhang threshold of 4 mm was best correlated with a diagnosis of impingement (sensitivity 79%, specificity 85%, PPV = 75%, NPV = 85%). Pain after THA related to iliopsoas impingement can be reasonably linked to acetabular overhang if it exceeds 4 mm on a CT scan. Below this threshold, it seems logical to look for another cause of iliopsoas irritation or another reason for the pain after THA before concluding impingement is present

The nerve roots of the cauda equina may be visualised by contrast-enhanced CT scans and by surface-coil MRI. We have identified the pattern of anatomy from L2-L3 to L5-S1 in 10 human cadaver specimens and correlated this with anatomical dissections. Individual roots are slightly more distinct on contrast-enhanced CT than on surface-coil MRI. There is a crescentic oblique pattern of nerve roots at the lower lumbar levels which is still apparent in the more crowded proximal sections. In all cases, the axial images correlated precisely with the dissections. Current imaging modalities can help the clinical understanding and management of abnormalities in this region of the spine

Patient specific instrumentation (PSI) for elective knee replacements in arthritic knees with severe deformities and in revision scenarios is becoming increasingly popular due to the advantage of restoring the limb axes, improved theatre efficiency and outcomes. Currently available systems use CT scan or MRI for pre-operative templating for design considerations with varied accuracy for sizing of implants. We prospectively evaluated 200 knees in 188 patients with arthritic knees with deformities requiring serial clinical assessment, radiographs and CT scans for PSI templating for TruMatch knee system (DepuySynthes, Leeds, UK). The common indications included severe arthritic deformities, previous limb fractures and in obese limbs with difficult clinical assessment. Surgical procedure was performed on standard lines with the customised cutting blocks. The ‘lead up’ time between the implant request and the operating date was 5 weeks on an average. We compared the pre op CT images and the best fit post-operative x- rays. The sizing accuracy for femur and tibia was 98.93 % and 95.75% respectively. All blocks fitted the femur and tibia. There were no bail outs, no cutting block breakage, 1 patient had residual deformity of 20 degrees, and 1 patient had late infection. The length of hospital stay, economic viability in terms of theatre turnover, less operating time, cost of sterilisation in comparison to conventional knee replacement surgery with other factors being unchanged was also assessed. The projected savings was substantial along with improved geometrical restoration of the knee anatomy. We recommend the use of PSI based on CT scan templating in difficult arthritic knees

Teratomas in the spinal cord are rare. We report a case in a 54-year-old man. CT scans revealed tumours of different densities within the spinal canal; this heterogeneity may help to differentiate teratoma from other spinal cord tumours. After resection of the tumours under microscopy, the result was excellent. Histological examination showed a variety of tissues, including elements of all three germinal layers

Introduction:. Fibular malreduction is a common and important cause of pain after surgical fixation following a syndesmosis injury, but it is unclear which components of malreduction correspond to clinical outcome. Plain radiographs have been shown to be unreliable at measuring malreduction when compared to CT scans. A number of published methods for measuring fibular position rely on finding the axis of the fibula. Elgafy demonstrated that fibular morphology varies greatly, and some studies have demonstrated difficulty finding the fibular axis. Methods:. We developed a new method of measuring the distal fibular position on CT images. We used CT studies in 16 normal subjects. Two assessors independently measured the ankle syndesmosis using the Davidovitch method, and our new protocol for fibular AP position, diastasis and fibular length. Results:. We demonstrated that after statistical analysis (Pearson Product Moment Correlation) our method showed improved inter-observer reliability (r = 0.99 and 0.95 vs 0.59 and 0.78 respectively) for diastasis and AP translation, and improved intra-observer reliability (r = 0.99 and 0.99 vs 0.91 and 0.97 respectively). We found inter and intra observer reliability of 0.80 and 0.91 respectively for fibular length, but were unable to find a novel, accurate method for measuring fibular rotation. Conclusions:. Our method is a new, simple, accurate and reproducible system for measuring the ankle syndesmosis. We believe that this method could be used to assess fibular reduction after obtaining CT images of the uninjured side for comparison