Sclerostin does not play a major role in the pathogenesis of skeletal complications in type 2 diabetes mellitus.

In contrast to previously reported elevations in serum sclerostin levels in diabetic patients, the present study shows that the impaired bone microarchitecture and cellular turnover associated with type 2 diabetes mellitus (T2DM)-like conditions in ZDF rats are not correlated with changes in serum and bone sclerostin expression. INTRODUCTION: T2DM is associated with impaired skeletal structure and a higher prevalence of bone fractures. Sclerostin, a negative regulator of bone formation, is elevated in serum of diabetic patients. We aimed to relate changes in bone architecture and cellular activities to sclerostin production in the Zucker diabetic fatty (ZDF) rat. METHODS: Bone density and architecture were measured by micro-CT and bone remodelling by histomorphometry in tibiae and femurs of 14-week-old male ZDF rats and lean Zucker controls (n = 6/group). RESULTS: ZDF rats showed lower trabecular bone mineral density and bone mass compared to controls, due to decreases in bone volume and thickness, along with impaired bone connectivity and cortical bone geometry. Bone remodelling was impaired in diabetic rats, demonstrated by decreased bone formation rate and increased percentage of tartrate-resistant acid phosphatase-positive osteoclastic surfaces. Serum sclerostin levels (ELISA) were higher in ZDF compared to lean rats at 9 weeks (+40 %, p < 0.01), but this difference disappeared as their glucose control deteriorated and by week 14, ZDF rats had lower sclerostin levels than control rats (-44 %, p < 0.0001). Bone sclerostin mRNA (qPCR) and protein (immunohistochemistry) were similar in ZDF, and lean rats at 14 weeks and genotype did not affect the number of empty osteocytic lacunae in cortical and trabecular bone. CONCLUSION: T2DM results in impaired skeletal architecture through altered remodelling pathways, but despite altered serum levels, it does not appear that sclerostin contributes to the deleterious effect of T2DM in rat bone.

Use of inertial measurement units to assess age-related changes in gait kinematics in an active population.

To study mobility in older populations it can be advantageous to use portable gait analysis systems, such as inertial measurement units (IMUs), which can be used in the community. To define a normal range, 136 active subjects were recruited with an age range of 18 to 97. Four IMUs were attached to the subjects, one on each thigh and shank. Subjects were asked to walk 10 m at their own self-selected speed. The ranges of motion of thigh, shank, and knee in both swing and stance phase were calculated, in addition to stride duration. Thigh, shank, and knee range of movement in swing and stance were significantly different only in the > 80 age group. Regressions of angle against age showed a cubic relationship. Stride duration showed a weak linear relationship with age, increasing by approximately 0.1% per year.

The anti-diabetic drug metformin does not affect bone mass in vivo or fracture healing.

SUMMARY: The present study shows no adverse effects of the anti-diabetic drug metformin on bone mass and fracture healing in rodents but demonstrates that metformin is not osteogenic in vivo, as previously proposed. INTRODUCTION: In view of the increased incidence of fractures in patients with type 2 diabetes mellitus (T2DM), we investigated the effects of metformin, a widely used T2DM therapy, on bone mass and fracture healing in vivo using two different rodent models and modes of metformin administration. METHODS: We first subjected 12-week-old female C57BL/6 mice to ovariectomy (OVX). Four weeks after OVX, mice received either saline or metformin administered by gavage (100 mg/kg/daily). After 4 weeks of treatment, bone micro-architecture and cellular activity were determined in tibia by micro-CT and bone histomorphometry. In another experiment, female Wistar rats aged 3 months were given only water or metformin for 8 weeks via the drinking water (2 mg/ml). After 4 weeks of treatment, a mid-diaphyseal osteotomy was performed in the left femur. Rats were sacrificed 4 weeks after osteotomy and bone architecture analysed by micro-CT in the right tibia while fracture healing and callus volume were determined in the left femur by X-ray analysis and micro-CT, respectively. RESULTS: In both models, our results show no significant differences in cortical and trabecular bone architecture in metformin-treated rodents compared to saline. Metformin had no effect on bone resorption but reduced bone formation rate in trabecular bone. Mean X-ray scores assessed on control and metformin fractures showed no significant differences of healing between the groups. Fracture callus volume and mineral content after 4 weeks were similar in both groups. CONCLUSIONS: Our results indicate that metformin has no effect on bone mass in vivo or fracture healing in rodents.

Influence of surgical preparation on the in-vivo response of osteochondral defects.

Cartilage has an extremely poor capacity to heal, which has lead to intensive research into biomaterials and tissue engineering for the purpose of regenerating cartilage in vivo. Many of these techniques have shown great promise in vitro; however, the results do not always carry across to the in-vivo scenario. Healthy cartilage autografts often do not integrate with the adjacent cartilage, suggesting that cartilage is rarely capable of healing even under ideal conditions. It is hypothesized in this study that the surgical creation of defects in cartilage causes significant damage to the adjacent tissues, leading to further degradation of the cartilage and poor outcome for the repair in general. This study compares the healing response of osteochondral defects created with either a punch or a drill in the weight-bearing region of the sheep knee at 4 and 26 weeks following surgery. The use of a drill to create the defect creates a more aggressive inflammatory response at 4 weeks compared with a punch. However, by 26 weeks, defects created with a punch scored higher on the O'Driscoll cartilage grading scale. Tissue damage at the time of surgery plays an important part in the sequence of events for healing of cartilage defects. This knowledge will help to characterize and refine the ovine model for cartilage regeneration and may have an influence on surgical technique and instrumentation for clinical cartilage repair.

Plaster of Paris-Short History of Casting and Injured Limb Immobilzation.

Various materials have been used since ancient times to help immobilise fractures. In this review, we discuss the history and developments of these materials as well as plaster of Paris. There has been a recent trend away from non-operative management of fractures, and skills in the use of plaster of Paris are declining. For the successful treatment of patients, it is important to appreciate how plaster works, how it should be used, and what can go wrong. In this review, we also discuss principles of applications and complications of plaster of Paris.

Screw fixation of medial malleolar fractures: a cadaveric biomechanical study challenging the current AO philosophy.

The AO Foundation advocates the use of partially threaded lag screws in the fixation of fractures of the medial malleolus. However, their threads often bypass the radiodense physeal scar of the distal tibia, possibly failing to obtain more secure purchase and better compression of the fracture. We therefore hypothesised that the partially threaded screws commonly used to fix a medial malleolar fracture often provide suboptimal compression as a result of bypassing the physeal scar, and proposed that better compression of the fracture may be achieved with shorter partially threaded screws or fully threaded screws whose threads engage the physeal scar. We analysed compression at the fracture site in human cadaver medial malleoli treated with either 30 mm or 45 mm long partially threaded screws or 45 mm fully threaded screws. The median compression at the fracture site achieved with 30 mm partially threaded screws (0.95 kg/cm(2) (interquartile range (IQR) 0.8 to 1.2) and 45 mm fully threaded screws (1.0 kg/cm(2) (IQR 0.7 to 2.8)) was significantly higher than that achieved with 45 mm partially threaded screws (0.6 kg/cm(2) (IQR 0.2 to 0.9)) (p = 0.04 and p < 0.001, respectively). The fully threaded screws and the 30mm partially threaded screws were seen to engage the physeal scar under an image intensifier in each case. The results support the use of 30 mm partially threaded or 45 mm fully threaded screws that engage the physeal scar rather than longer partially threaded screws that do not. A 45 mm fully threaded screw may in practice offer additional benefit over 30 mm partially threaded screws in increasing the thread count in the denser paraphyseal region.

"When can I return to driving?": a review of the current literature on returning to driving after lower limb injury or arthroplasty.

Clinicians are often asked by patients, "When can I drive again?" after lower limb injury or surgery. This question is difficult to answer in the absence of any guidelines. This review aims to collate the currently available evidence and discuss the factors that influence the decision to allow a patient to return to driving. Medline, Web of Science, Scopus, and EMBASE were searched using the following terms: 'brake reaction time', 'brake response time', 'braking force', 'brake pedal force', 'resume driving', 'rate of application of force', 'driving after injury', 'joint replacement and driving', and 'fracture and driving'. Of the relevant literature identified, most studies used the brake reaction time and total brake time as the outcome measures. Varying recovery periods were proposed based on the type and severity of injury or surgery. Surveys of the Driver and Vehicle Licensing Agency, the Police, insurance companies in the United Kingdom and Orthopaedic Surgeons offered a variety of opinions. There is currently insufficient evidence for any authoritative body to determine fitness to drive. The lack of guidance could result in patients being withheld from driving for longer than is necessary, or returning to driving while still unsafe.

Assessment of validity, reliability, responsiveness and bias of three commonly used patient-reported outcome measures in carpal tunnel syndrome.

BACKGROUND: In recent years there has been an increase in the use of self-administered questionnaires to accurately assess intervention outcomes in hand surgery in order to determine the quality of healthcare. This prospective study aims to evaluate and assess the validity, reliability, responsiveness, and bias of a number of outcome measure for Carpal Tunnel Syndrome (CTS) including the disease-specific Boston questionnaires (BQ), and the region-specific Disability of Arm, Shoulder, and Hand (DASH) questionnaires and Manchester Modified Disabilities of the Arm, Shoulder and Hand (M(2)DASH) questionnaires, and comparing the results to Nerve Conduction Studies (NCS). MATERIALS AND METHODS: Forty-eight patients with clinical signs of CTS confirmed by NCS completed the BQ, DASH and M(2)DASH questionnaire at different time intervals peri-operatively. The scores were analysed to assess validity, reliability, responsiveness, and bias of the questionnaires. Validity analysis for the three questionnaires showed strong positive correlations and there was no age, gender, hand dominance, or side affected bias in the questionnaires. RESULTS: No significant correlation was obtained between the questionnaires and NCS. Significant results for responsiveness were noted in BQ symptom severity scale only. CONCLUSION: 1. This study ha show n that the BQ, DASH and M(2)DASH questionnaires are valid and reliable outcome measures for CTS. 2. In terms of responsiveness, the DASH and M(2)DASH questionnaires are not as responsive as the BQ scores over the initial post-operative recovery period. 3. We would therefore recommend that the Boston Questionnaire be used to assess early post-operative patient related outcome measures for Carpal Tunnel Syndrome.

Carpal tunnel syndrome: a review of the recent literature.

Carpal Tunnel Syndrome (CTS) remains a puzzling and disabling condition present in 3.8% of the general population. CTS is the most well-known and frequent form of median nerve entrapment, and accounts for 90% of all entrapment neuropathies. This review aims to provide an overview of this common condition, with an emphasis on the pathophysiology involved in CTS. The clinical presentation and risk factors associated with CTS are discussed in this paper. Also, the various methods of diagnosis are explored; including nerve conduction studies, ultrasound, and magnetic resonance imaging.