Introduction. Symptomatic hip dysplasia is often treated with periacetabular osteotomy (PAO). Studies investigating the effect of PAO have primarily focused on radiographic measurements, pain-related outcomes, and hip survival whereas evidence related to sport participation is limited. Methods. All patients in our institutional database were deemed eligible for this cohort study if they underwent PAO and had answered at least one question related to sport participation. Patients were asked if they were playing sport preoperatively, 6 months after PAO as well as 2, 5, 10, 15 and 20 years after. In addition, patients were asked if they were able to play their preferred sport, what type and at what level they were playing sport, and if surgery had improved their sport performance. Results. Among 2398 patients surveyed, 1926 (80%) were included and 56% were playing sport 6 months after PAO. This number was 61% two years after PAO, and remained around that for the following years, before dropping 15 years after PAO. Between 56% and 71% of patients felt that their sporting performance improved following PAO at the different time points. Between 39% (6 months after PAO) and 63% (15 years after PAO) were able to participate in their preferred sport. Conclusion. The majority of patients undergoing PAO due to hip dysplasia will return to, and maintain, sport after PAO. More than half of patients undergoing PAO believe that the surgery improved their sports performance, and long after the surgery more than half of patients undergoing PAO are able to play their preferred sport

Summary. The ankle X-ray has moderate diagnostic power to identify syndesmotic instability, showing large sensitivity ranges between observers. Classification systems and radiographic measurements showed moderate to high interobserver agreement, with extended classifications performing worse. Introduction. There is no consensus regarding the diagnosis and treatment of ankle fractures with respect to syndesmotic injury. The diagnosis of syndesmotic injury is currently based on intraoperative findings. Surgical indication is mainly made by ankle X-ray assessment, by several classification systems and radiographic measurements. Misdiagnosis of the injury results in suboptimal treatment, which may lead to chronic complaints, like instability and osteoarthritis. This study investigates the diagnostic power and interobserver agreement of three classification methods and radiographic measures, currently used to assess X-ankles and to identify syndesmotic injury. Patients and Methods. Twenty patients (43.2 ± 15.3yrs) with an ankle fracture, indicated for surgery, were prospectively included. All patients received a preoperative ankle X-ray, which was assessed by several observers: two orthopaedic surgeons, one trauma surgeon and two radiologists. The ankle X-ray was assessed on syndesmotic injury/stability and presence of fractures (fibula, medial/tertius malleolus). Three classification systems were used: Weber, AO-Müller (short-version n=3 options; extended-version n=27 options), Lauge-Hansen (short-version n=5 options; extended-version n=17 options) and two radiographic measurements were done: tibiofibular overlap (TFO) and ratio medial clearspace/superior clear space (MCS/SCS). All observers were instructed about the assessments before the measurements. During surgery, a proper intraoperative description of the syndesmosis was noted. Agreement (%), Intraclass Correlation Coefficients (ICC) and Kappa were calculated to determine interobserver agreement. Kappa statistic was interpreted according to Landis and Koch. To test the diagnostic power of ankle X-rays to identify syndesmotic instability, sensitivity and specificity were calculated with intraoperative findings serving as golden standard. Results. Six of 20 ankles showed syndesmotic instability intraoperatively. An overall sensitivity of 43% (specificity: 78) was found for X-rays in identifying syndesmotic instability, showing a wide range in sensitivity between observers (17–83%), with radiologists performing better (range 50–83%) than surgeons (range: 17–33%). Overall, substantial to perfect interobserver agreement (range 70–100%) was found for all short classification systems, showing an average kappa ≥0.60. The agreement reduced for more extended classification systems. E.g. observer agreement for the AO-Muller classification with 3, 9 and 27 options was respectively 85% (kappa 0.66), 68% (kappa 0.57) and 55% (kappa 0.51). One observer deviated slightly from others in all classification assessments. Removing this observer resulted in excellent agreement for all classification systems (>90%). Radiographic measurements showed moderate to high interobserver agreement, with TFO performing best (avg. ICC 0.88). Discussion/Conclusion. In ankle fractures, a preoperative X-ray has low sensitivity in detecting syndesmotic instability, showing large sensitivity ranges between observers. Further study is needed to investigate the contribution of classification systems in determining the best treatment method for syndesmotic injury. Ankle X-ray assessment using the three classification systems and radiographic measures was consistent among observers. Disagreement between observers can be attributed to intrinsic differences among the systems (e.g. stepwise classification vs. single assessment). No preference for one specific classification was found, as all showed comparable interobserver agreement. However classification systems with few options are recommended, as the observer agreement reduced with more extending classifications

The effect of bisphosphonates on the mechanical properties of the uninjured contra-lateral cortical bone during fracture healing is poorly reported. There remains conflicting evidence with regards the effect of bisphosphonate therapy on cortical bone strength. We assessed the effect of nine weeks of Ibandronate therapy, in a dose known to preserve cancellous bone BMD and strength, on the mechanical properties of the uninjured rat tibial diaphyses using a standardised model of tibial osteotomy and plate fixation. Skeletally mature ex-breeder rats were used. Stress at failure of the tibial diaphyses was measured by a four-point bending test using a custom made jig for rat tibiae. The mechanical strength was compared with radiographic measurements of bone density. Animals received daily subcutaneous injections. 11 rats received 1μg/kg Ibandronate (IBAN) daily and 17 rats received 1ml 0.9% Sodium Chloride (CONTROL) daily. The IBAN group had a statistically significant, p=0.024, higher stress at failure 212.7 (±42.04) MPa compared to the CONTROL group 171.7 (±46.13)MPa. There was a positive correlation between the mechanical strength of bone and the radiological measure of bone density. Osteopenia is known to occur following a fracture even in the contra-lateral limb. This study demonstrates that ibandronate therapy has no detrimental effect and may even increase the strength of uninjured cortical bone during the fracture healing process. The longer term effect of ibandronate on cortical bone especially in relation to the accumulation of mico-damage requires further study. Bisphosphonate effect on the uninjured limb needs to be considered when reporting proportional strength of fracture repair compared to the uninjured limb

Summary. Bi-plane Image matching method is very useful technique to evaluate the loaded 3D motion of each cervical level. Introduction. Cervical orthoses are commonly used to regulate the motion of cervical spines for conservative treatment of injuries and for post-operative immobilization. Previous studies have reported the efficacy of orthoses for 2D flex-extension or 3D motions of the entire cervical spine. However, the ability of cervical orthoses to reduce motion might be different at each intervertebral level and for different types of motion (flexion-extension, rotation, lateral bending). The effectiveness of immobilizing orthoses at each cervical intervertebral level for 3D motions has not been reported. The purpose of this study is to evaluate the effectiveness of the Philadelphia collar to each level of cervical spines with 3D motion analysis under loading condition. Patients & Methods. Patient Sample: Four asymptomatic volunteer subjects were recruited and provided informed consent. Approval of the experimental design by the institutional review board was obtained. These 4 individuals were without any history of cervical diseases or procedures. The presence of any symptoms, spinal disorders and anatomical abnormalities in fluoroscopic images or CT was a criterion of exclusion from this study. Outcome Measures: To evaluate the efficacy of the Philadelphia collar, ANOVA was used to compare the range of motion with and without collar at the C3/4, C4/5, C5/6 and C6/7 intervertebral levels for each motion. The level of statistical significance was set at p<0.05. When a statistical difference was detected, post hoc Tukey tests were performed. Methods. Three-dimensional models of the C3-C7 vertebrae were developed from CT scans of each subject using commercial software. Two fluoroscopy systems were positioned to acquire orthogonal images of the cervical spine. The subject was seated within the view of the dual fluoroscopic imaging system. Pairs of images were taken in each of 7 positions: neutral posture, maximum flexion and extension, maximum left and right lateral bending, and maximum left and right rotation. The images and 3D vertebral models were imported into biplane 2D-3D registration software, where the vertebral models were projected onto the pair of digitised images and the 3D bone pose was adjusted to match its radiographic projection in each image. Relative motions between each vertebral body were calculated from body-fixed coordinate systems using a flexion-lateral bending-axial rotation Cardan angle sequence. Results. Flexion range was significantly reduced with the collar at each cervical level. Extension range was significantly reduced at the C3/4 level. Rotation and lateral bending were reduced for C3/4, C4/5, C5/6 levels with the collar. Discussion/Conclusion. The Philadelphia Collar significantly reduces cervical motion at C3/4, C4/5 and C5/6 levels in almost all motions (except for extension). At the C6/7 level, this type of collar has limited effectiveness reducing cervical motion. We used 3D radiographic measurements to quantify the effectiveness of the Philadelphia collar for reducing cervical motion. Bi-plane 2D-3D registration method is useful technique to evaluate 3D motion of cervical spines

We investigated the effects of low-intensity pulsed ultrasound on distraction osteogenesis in a rabbit model. Callotasis of the right tibia was performed in 70 male Japanese white rabbits using mini-external fixators. In the first part of the study in 64 animals using normal distraction (waiting period seven days; distraction rate 0.5 mm/12 hours; distraction period ten days), we evaluated the distraction site by radiography, measurement of the bone mineral density (BMD), mechanical testing, and histology. In the second part in six rabbits using fast distraction (waiting period 0 days; distraction rate 1.5 mm/12 hours; distraction period seven days) the site was evaluated radiologically. Half of the animals (35) had received ultrasound to their right leg (30mW/cm. 2. ) for 20 minutes daily after ceasing distraction (ultrasound group), while rigid fixation only was maintained in the other half (control group). With normal distraction, the hard callus area, as shown by radiography, the BMD, and the findings on mechanical testing, were significantly greater in those receiving ultrasound than in the control group. Histological analysis showed no tissue damage attributable to exposure to ultrasound. With fast distraction, immature bone regeneration was observed radiologically in the control group, while bone maturation was achieved in the ultrasound group. We conclude that ultrasound can accelerate bone maturation in distraction osteogenesis in rabbits, even in states of poor callotasis

The function of the knee joint is to allow for locomotion and is comprised of various bodily structures including the four major ligaments; medial collateral ligament (MCL), lateral collateral ligament (LCL), anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). The primary function of the ligaments are to provide stability to the joint. The knee is prone to injury as a result of osteoarthritis as well as ligamentous and meniscal lesions. Furthermore, compromised joint integrity due to ligamentous injury may be a result of direct and indirect trauma, illness, occupational hazard as well as lifestyle. A device capable of non-invasively determining the condition of the ligaments in the knee joint would be a useful tool to assist the clinician in making a more informed diagnosis and prognosis of the injury. Furthermore, the device would potentially reduce the probability of a misdiagnosis, timely diagnosis and avoidable surgeries. The existing Laxmeter prototype (UK IPN: GB2520046) is a Stress Radiography Device currently limited to measuring the laxity of the MCL and LCL at multiple fixed degrees of knee flexion. Laxity refers to the measure of a ligament's elasticity and stiffness i.e. the condition of the ligament, by applying a known load (200N) to various aspects of the proximal tibial and thereby inducing tibial translation. The extent of translation would indicate the condition of the ligament. The Laxmeter does not feature a load applying component as of yet, however, it allows for the patient to be in the most comfortable and ideal position during radiographic laxity measurement testing. The entire structure is radiolucent and attempts to address the limitations of existing laxity measurement devices, which includes: excessive radiation exposure to the radiographic assistant, little consideration for patient ergonomics and restrictions to cruciate or collateral ligament laxity measurements. The study focusses on further developing and modifying the Laxmeter to allow for: the laxity measurement of all four major ligaments of the knee joint, foldability for improved storage and increased structural integrity. Additionally, a load applicator has been designed as an add-on to the system thereby making the Laxmeter a complete Stress Radiography Device. Various materials including Nylon, Polycarbonate, Ultra High Molecular Weight Polyethylene (UHMWPE) – PE 1000, and Acetal/ POM were tested, using the Low Dose X-ray (Lodox) scanner, to determine their radiolucency. All materials were found to be radiolucent enough for the manufacture of the Laxmeter structure as well as the load applicator in order to identify and measure the translation of the tibia with respect to the stationary femur. The Laxmeter allows for the measurement of the laxity of the MCL and LCL at multiple fixed degrees of flexion by providing the ideal patient position for testing. The next iteration of the device will present an affordable and complete Stress Radiography Device capable of measuring the laxity of all four major ligaments of the knee joint at multiple fixed degrees of flexion. Future work would include aesthetic considerations as well as an investigation into carbon-fibre-reinforced plastics