Clinical management of ankle injuries often involves use of braces to provide pain relief and stability. Individuals with braced ankles may be at more risk of injury while turning. The aim of this study was to evaluate the biomechanical effects of one of the commonly prescribed pneumatic ankle braces on gait parameters while turning. Three-dimensional gait data was collected using a 7 camera, VICON 612 (Oxford Metric, UK) motion analysis system (120 HZ) synchronised with a single Kistler force plate embedded in the floor and set at a sampling frequency of 600HZ. Sixteen retro-reflective markers were attached to anatomical landmarks on both lower limbs and pelvis using wig tape. In the case of the braced ankle, markers were attached on the brace over the respective body landmarks. Out of ten trials, five were performed with and the other five without brace. Comparative results were produced between braced and un-braced ankle during turning at 90 degrees with the right foot landing on the force plate and turning right. Results show that use of brace is effective in reducing gross moments about the ankle joint even at the time of turning but it does not totally eliminate motion. Both conditions showed different rotation moments at knee but hip rotation moments were not affected by the brace. Knee rotation moment without brace was mainly in internal rotation (0.301Nm/kg) towards the terminal stance phase and it reduced to 0.128Nm/kg by bracing the ankle. A new type of turning strategy was identified where the subject pre-planned the turn in late swing phase before landing on the ground probably to avoid a fall. It is important that patients with ankle injuries receive supervised gait training to improve their turning confidence during their rehabilitation therapy.
Pelvic packing in exanguinating pelvic trauma:
2.2% fully confidentto manage such a case. A positive correlation exists between increasing training and confidence. 58.9% have never seen such a case. No correlation exists between time in training and exposure. 62.8% report training in this case inadequate. A positive correlation exists between time in training and perceived inadequacy of ability to manage such a case. Junctional traum with non-compressible groin haemorrhage:
0.4% fully confident. A positive correlation exists between time in training and confidence. 73.0% have never seen such a case. 67.9% report training in this case inadequate. No correlation was found between time spent in training and perceived training adequacy. Blood product resuscitation in trauma:
11.6% were fully confident. 18.8% have never seen such a case. No correlation exists between time in training and confidence or exposure. 45.0% report training as inadequate in this case. No correlation seen between time in training and perceived training adequacy.
The quality of care afforded to service personnel and civilians in recent conflict is unsurpassed and it is essential that the lessons learnt by deployed surgeons form a continuum to their successors. For military orthopaedic trainees this reinforces the need for closely supervised secondments on deployment; attendance at established military surgical training courses and appropriate fellowships to maximise exposure prior to first consultant deployment.
Limb viability:
27.8% were fully confident. A positive correlation exists between training year and fully confident reports. 68.6% encounter such injury either every six months or less frequently. 18.6% regard their training in these cases inadequate. No correlation seen between experience and perceived adequacy of training. Amputation:
10.3% were fully confident. A positive correlation exists between time in training and perceived fully confident reports. 57.3% encounter such injury either every six months or less frequently. 36.3% regard their training in these cases inadequate. No correlation seen between experience and exposure to cases or perceived adequacy of training.
Military orthopaedic surgeons are providing injured service personnel and civilians with the best possible chance of successful rehabilitation from these injuries. It is fundamental that the experience of these individuals is accessible to their successors. For military trainees, this reinforces the need for participation in closely supervised secondments on deployment, attendance at established military surgical training courses and appropriate fellowships to maximise exposure prior to completion of training and first consultant deployment.
The purpose of this study was to determine if routine x-ray exposure produced any chemical oxidation of Ultra High Molecular Weight Polyethylene (UHMWPE), used for joint arthroplasty. Three different polyethylene polymers were obtained from Biomet, Depuys and Howmedica. These samples had undergone sterilisation and packaging methods. Rectangular shapes of polymer were cut according to the standards specified by the ASTM (American Society For Testing and Materials). Eight samples of each polymer were obtained and divided randomly in to test and control subgroups. The test samples were exposed to ten x-rays with the standard dose used for the hip joint. Polyethylene oxidation was measured using Fourier transform infrared spectroscopy. This technique can assess the incorporation of oxygen within the carbonyl region. Radiated and non-irradiated samples were compared in each polymer group. Oxidation from the Fourier transform infrared spectroscopy was quantified by calculating the area under a signature absorption peak for UHMWPE (methylene band at 1370 cm-1) and an oxidation absorption peak (carbonyl band at 1720 cm-1). The ratio of the area of the oxidation peak to the area of the signature peak yields the carbonyl content, or oxidation, relative to the amount of polyethylene. There was no significant difference in oxidation after exposure to x-rays between test and control UHMWPE samples. Although numerous studies have looked in to the effects of high dose radiation exposure on polyethylene, effects of routine x-rays have not been studied before. It is common practice to follow-up patients with joint replacements over a long period with xrays at each visit. Present study examined the effects of routine x-rays on oxidation of polyethylene. However there was no detectable oxidation after exposure to x-rays. This study paves way for further research in this direction.
This study details the development of this model and its validation against the accepted Stenmore Test Rig for modelling of knee joint movement and knee prosthetic wear. The validation results will be presented, The model allows the calculation and representation of contact pressures and contact areas in the knee joint as it moves through the gait cycle. This study also shows the effect of uni-condular loading and varus mal-positioning which may occur at surgery and the effect this has on the contact area and contact pressures of a prosthetic knee in ambulation. The resultant gait pattern produced by uni-condular loading and exhibited by the virtual knee closely resembles that seen in In Vivo Kinematic Studies reported by other authors. In conclusion we present this as a valid computational dynamic model of knee prosthetic wear and kinematics which represents an enormous advantage over standard mechanical testing and presents possibilities for rapid analysis in new knee joint designs and the effect of abnormalities of gait and wear.