Examining agreement between finite element modelling methodologies in predicting pathological fracture risk in proximal femurs with bone metastases.

BACKGROUND: Finite element modelling methodologies available for assessing femurs with metastases accurately predict strength and pathological fracture risk which has led them to being considered for implementation into the clinic. However, the models available use varying material models, loading conditions, and critical thresholds. The aim of this study was to determine the agreement between finite element modelling methodologies in assessing fracture risk in proximal femurs with metastases. METHODS: CT images of the proximal femur were obtained of 7 patients who presented with a pathologic femoral fracture (fracture group) and the contralateral femur of 11 patients scheduled for prophylactic surgery (non-fracture group). Fracture risk was predicted for each patient following three established finite modelling methodologies which have previously shown to accurately predict strength and determine fracture risk: non-linear isotropic -based model, strain fold ratio -based model, Hoffman failure criteria -based model. FINDINGS: The methodologies demonstrated good diagnostic accuracy in assessing fracture risk (AUC = 0.77, 0.73, and 0.67). There was a stronger monotonic association between the non-linear isotropic and Hoffman -based models (τ = 0.74) than with the strain fold ratio model (τ = -0.24 and - 0.37). There was moderate or low agreement between methodologies in discriminating between individuals at high or low risk of fracture (κ = 0.20, 0.39, and 0.62). INTERPRETATION: The present results suggest there may be a lack of consistency in the management of pathological fractures in the proximal femur based on the finite element modelling methodologies.

The use of denosumab in the setting of acute pathological fracture through giant cell tumour of bone.

BACKGROUND: Denosumab (XgevaTM) is a fully human antibody to RANK-Ligand, an important signal mediator in the pathogenesis of giant cell tumour of bone (GCTB). The use of denosumab in the treatment of GCTB has changed the way in which these tumours are managed over the past years. CASE PRESENTATION: Described is the case of an acute fracture through a GCTB of the distal radius of a fit and well 32-year-old, non-smoking, female patient following a simple fall onto her outstretched, dominant hand. The aim was to enable joint sparing management for the patient, as opposed to an acute fusion procedure of the carpus. The patient underwent percutaneous k-wire fixation with application of plaster and immediate commencement with denosumab to halt the activity of the GCTB. Bone healing was rapid; plaster and k-wires were removed after 6 weeks. At 6 months denosumab, was ceased and an open curettage and grafting procedure of the tumour bed was undertaken (using MIIG X3, Wright Medical, aqueous calcium sulphate as graft material). CONCLUSIONS: The use of denosumab in the acute setting of pathological fracture through giant cell tumour of bone allowing joint salvage has not been previously described. The treatment was well tolerated and functional outcomes are excellent, with very promising 4-year follow-up. This novel approach may allow for more joint sparing strategies in the future for other patients in this difficult situation. Further cases will need to be gathered to establish this technique as a suitable treatment pathway.

Design and establishment of a cancer registry: a literature review.

BACKGROUND: Establishment of a cancer registry is a complex process that requires substantial resources and careful planning. There are numerous resources available to provide guidance for this, which include guidelines and frameworks of varying quality. It is the authors' goal to identify evidence-based recommendations within the literature to help guide the process of designing a new registry with optimal efficiency, workability and data use. The objective of this study is to examine the primary literature for evidence-based recommendations on how to design and establish a cancer registry, with a focus on literature which analyses the performance and usefulness of already established registries or guidelines. METHODS: An electronic search was completed in MEDLINE, CINAHL, EMCARE, SCOPUS and the Cochrane Database of Systematic Reviews. Recommendations were extracted from the identified articles and collated as themes. RESULTS: Nine articles of varying quality were included in the review. Recommendations obtained from the literature included broad themes of the importance of clinician involvement, establishment of clear data definitions, number of variables used, inbuilt strategies to improve quality and completeness of data, considerations of costs, an 'opt-out' strategy for ethics and privacy and flexibility of the system. CONCLUSION: This review concluded that there is a large gap in the primary literature for evidence-based recommendations on the design and establishment of cancer registries. The included articles established a small scope of relevant themes, which were largely non-specific. This area of deficiency provides an opportunity for future research, which would further strengthen the quality of current or new guidelines in cancer registry establishment.

Treatment of partial distal biceps tendon tears.

Partial rupture of the distal biceps tendon exhibits features similar to that of complete disruption, including acute antecubital pain, weakness of elbow flexion, and forearm supination, and differs only in the fact that the biceps tendon is still palpable in the partial rupture. There are 2 etiologies, first acute traumatic (such as a sudden eccentric contracture) and second, chronic degenerative tendon disease. For accurate diagnosis, a high index of suspicion must be employed. Initial investigations should include plain x-ray and a magnetic resonance scan. Partial tears <50% may be treated with nonoperative management or with surgical debridement of the surrounding synovitis. Tears >50% should be treated with division of the remaining tendon and surgical repair of the entire tendon as a single unit. Surgical endoscopy provides the ability to further quantify the extent of a distal biceps tear and to treat with debridement. This technique, however, should only be used in experienced hands.

Measuring tip-apex distance using a picture archiving and communication system (PACS).

BACKGROUND: The sliding hip screw is currently the most frequently used prosthesis used to fix trochanteric fractures of the hip. The 'tip-apex distance' (TAD) has been found to be predictive of hardware failure, with a larger TAD being associated with an increasing risk of 'cut-out'. Previous studies have either used 'hard-copy' radiographs and geometrical aids or a mixture of scanned hard-copy images and extra software to measure TAD. The current study describes a new method of tip-apex distance estimation using an entirely digital picture archiving and communication system (PACS). MATERIALS AND METHODS: Ten radiographs were measured for TAD by four surgeons of differing experience using the described measurement protocol, at two different time points (4 weeks apart). The results were then subjected to two-tailed t-tests to determine if they differed significantly. RESULTS: No tests attained significance (i.e. no statistical difference existed between the observers' measurements and no difference existed over time from a single observer's results). CONCLUSION: This study shows that TAD can be easily, accurately and, importantly, reproducibly measured using an entirely digitally based image capture and archiving system. The ease with which the measurements and calculations can be made will facilitate orthopaedic practitioners and trauma units in their auditing activities, and allows for quick TAD estimation in the 'X-ray meeting' environment.

Homicide-suicide (dyadic death), homicide, and firearms use in England and Wales.

Homicide-suicide forms a distinct form of homicide. An analysis of cases in the Yorkshire and Humberside region of England between 1991 and 2005 revealed 37 episodes with 42 victims. Previous studies have shown a high rate of use of firearms. Over the last 2 decades firearms legislation has become more restrictive. In this study all assailants were male, mean age 46.8 years. The commonest method of homicide was strangulation (36%) with 16% killed by firearms. This is a reduction compared with a previous study in the same region. All killers who shot their victims killed themselves with firearms. There were no multiple killings with firearms in this study and no stranger killings. Hanging was the commonest method of suicide. During the same period the use of firearms as a method of homicide increased in England and Wales with handguns, the most common weapon. Nationally, suicide after homicide has remained at a similar rate over the half century and is an uncommon phenomenon. Firearms use remains low in both homicide and homicide-suicide episodes in England, and further analysis is required to determine changes in patterns of killing.

Multiparameter quantitative computer-assisted tomography assessment of unicompartmental knee arthroplasties.

BACKGROUND: Unicompartmental knee arthroplasty is a popular alternative to total knee replacement in selected patients. Component alignment has not yet been described by computer-assisted tomography (CAT) imaging techniques; these have been developed for total knee arthroplasty analysis. The aims of this study were to report two new technologies; a new unicompartmental knee arthroplasty system was radiographically assessed with a new CAT scan protocol. METHODS: In a consecutive cohort study, 60 knees were analysed by the 'UniCAT Protocol'. Patients were implanted with a unicompartmental knee arthroplasty system that uses a unique ligament tensor for femoral component alignment. The uniCAT protocol requires a long anteroposterior and lateral scout scan to measure limb alignment and component orientation. A spiral computer-assisted tomography at the knee is used to measure component rotation. The total scan time was 20 s with a calculated unshielded radiation dose of 1 mSv or less. RESULTS: The mechanical axis had a mean of 2.7 degrees varus. Femoral components were implanted with a mean of 0.37 degrees valgus and 1.3 degrees flexion. Tibial components were implanted with a mean 3.47 degrees varus and 5.1 degrees posterior slope. Femoral components were externally rotated a mean of 3.36 degrees, tibial components were externally rotated 6.59 degrees from the posterior tibia and 5.68 degrees from the transepicondylar axis. CONCLUSION: The UniCAT protocol uses less radiation than whole-limb spiral scans and is a method that can be used with all modern computer-assisted tomography machines. The coronal and sagital alignment results compare favourably with previous published reports without computer-assisted tomography. Component rotation has not previously been reported and its implications are yet to be defined.

Trimodal death and the injuries of survivors in Krabi Province, Thailand, post-tsunami.

26 December 2004 is a date that changed the lives of incalculable numbers of persons the world over as a result of the Asian tsunami. Krabi Province was one of the more severely affected areas of Thailand, with many of the dead and injured being non-Thai, persons who were holidaying during the peak tourist season. Some injury types were comparatively underrepresented, such as head, thoracic and abdominal trauma. Does the classic trimodal distribution of death following injury help explain the types of injuries seen in the survivors of the disaster? Data are incomplete at this point in time, but with time it may be found that the trimodal model displays the pattern of death in mass casualty disaster situations. This may aid in the development of specific strategies to deal with similar events in the future.

Trauma response to the Asian tsunami: Krabi Hospital, Southern Thailand.

The date 26 December 2004 saw a massive tidal wave propagated from a 9.0 Richter scale suboceanic earthquake off the coast of Sumatra in South-East Asia. It swept across the Indian Ocean over a matter of hours leaving destruction in its wake. In Southern Thailand, Krabi Hospital, that province's major tertiary health centre, received the majority of the region's tsunami victims. Well-rehearsed contingency plans were in place to cope with 10, 20 and 40 trauma victims in the case of an extreme event. By the end of 26 December some 500 injured people had been treated at Krabi Hospital: well in excess of the 'worst case scenario' planning. Over the following days a total of 1357 tsunami victims were treated. Over the course of the day victims were able to move through the hospitals' system and gain appropriate treatment. This was achieved through the almost superhuman dedication of the hospitals' well-trained nursing and medical staff. In addition to this were large numbers of both Thai and foreign volunteers, who aided people with basic necessities such as providing them with food, water and clothing as well as simple human comfort, some also acting as translators for the health-care workers and the masses of injured and displaced people. Makeshift wards were constructed in halls and little used areas of the hospital, using army style stretchers to accommodate the wounded. Even though the disaster contingency plans at Krabi Hospital were utterly overrun, the fact that well-thought out and practised strategies were in place saved incalculable lives. The message is clear: practised responses to mass trauma situations will save lives and allows health-care teams to coordinate well in the face of overwhelming odds without panic. All centres should routinely practise disaster response through scenario-based training.