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OBJECTIVES: To compare early outcomes of proximal femoral bionic nail (PFBN), Inter-TAN, proximal femoral nail antirotation (PFNA) for intertrochanteric fractures in elderly patients. METHODS: Eighty-two elderly patients with intertrochanteric femoral fractures treated at Xiangyang No. 1 People's Hospital affiliated with Hubei University of Medicine from December 2021 to 2022 were retrospectively analyzed. They were categorized into three surgical groups: PFBN (22 cases), Inter-TAN (20 cases), and PFNA (40 cases). Preoperative demographics and fracture characteristics were compared, alongside intraoperative and postoperative metrics like operative time and complication rates. RESULTS: In the PFBN group, operative time, fluoroscopy use, blood loss, and transfusion were higher, but postoperative weight-bearing, healing, and hospital stay were shorter compared to the Inter-TAN and PFNA groups (P<0.05). Inter-TAN had a significantly shorter postoperative weight-bearing time than PFNA (P<0.001). Other compared factors showed no significant differences between groups (P>0.05), including complication rates and scores at 6-month follow-up. CONCLUSIONS: PFBN, a novel surgical approach for intertrochanteric fractures in elderly patients, outperforms Inter-TAN and PFNA by accelerating early weight-bearing and hastening fracture recovery.

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Osgood Schlatter's disease (OSD) is characterized by pain at the tibial tuberosity provoked during knee-loading activities, and is common in adolescent athletes. The aim of this study was to characterize clinical, pain and ultrasound imaging characteristics in participants with OSD compared to controls. This cross-sectional study included adolescents diagnosed with OSD and matched controls. Following baseline evaluation including ultrasound, participants completed the following aggravating activities in a randomized order: single-leg isometric knee hold, single-leg squat, single-leg vertical jump, hopping, running, cutting, lunges, and walking. Participants rated pain intensity on a numeric rating scale (0-10; no pain to worst pain imaginable) and localization during activities. We included 35 participants with OSD (48.5% females, age 13.0 [SD 1.5]) and 21 controls (47.6% females, age 13.4 [SD1.4]). Doppler signal was more prevalent in OSD participants at the tendon (77% vs. 30%) and tuberosity (29% vs. 10%). Tendon thickness was greater in OSD at distal (mean difference = 4.5 mm 95% CI 1.5-7.5) and proximal sites (mean difference = 4.2 95% CI 0.1-8.3). Aggravating activities induced higher pain in OSD. The greatest differences between OSD and control were the dynamic single-leg squat (mean difference = 4.2 (95% CI 3.22-5.1)). Pain was localized at the tibial tuberosity and patellar tendon during activities. Sex, sports participation, bilateral pain, and Doppler were associated with greater pain during aggravating activities. Single-leg activities loading the tibial tuberosity through the tendon appear to provoke OSD-related pain more than other sports specific movements. This may be useful to guide adolescents on which activities are likely to aggravate pain.

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OBJECTIVE: To investigate in vivo 6-degree-of-freedom (DOF) vertebral motion in patients with isthmic spondylolisthesis (IS) during various functional weight-bearing activities. METHODS: Fifteen asymptomatic volunteers (mean age 54.8 years) and fourteen patients with IS at L4-5 (mean age 53.4 years) were recruited. The positions of the vertebrae (L4-L5) in the supine, standing, flexion-extension, left-right twisting and left-right bending positions were determined using previously described CT-based models and dual fluoroscopic imaging techniques. Local coordinate systems were established at the center of the anterior vertebra of L4 isthmic spondylolisthesis (AIS), the posterior lamina of L4 isthmic spondylolisthesis (PIS) and the center of the L5 vertebra to obtain the 6DOF range of motion (ROM) at L4-L5 and the range of motion (ROM) between the AIS and the PIS. RESULTS: The translation along the anteroposterior axis at L4-L5 during flexion-extension, left-right bending and left-right twisting was significantly greater than that of the healthy participants. However, the translation along the mediolateral axis at L4-L5 presented paradoxical motion under different positions: the ROM increased in the supine-standing and flexion-extension positions but decreased in the left-right bending and left-right twisting positions. The separation along the anteroposterior axis during flexion was significantly greater than that during standing, on average, reaching more than 1 mm. The separation along the mediolateral axis during standing, flexion and extension was significantly greater than that in the supine position. CONCLUSIONS: This study revealed the occurrence of displacement between the AIS and PIS, primarily in the form of separation during flexion. Symptomatic patients with isthmic spondylolisthesis exhibit intervertebral instability, which might be underestimated by flexion-extension radiographs.

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Ankle fractures account for 10 % of all fractures in adults. The incidence of ankle fractures is rising, particularly as the population ages. Two thirds are isolated malleolar fractures. The most used classifications are anatomical, Weber's and Lauge-Hansen's classifications. The treatment of lateral malleolar fractures may be conservative or surgical, depending on the ankle stability. To test this, a weight-bearing X-ray is required. If this is not possible on the day of trauma, it can be done 7 days later. Conservative treatment consists of a six-week immobilization in a splint or plaster cast, with weight-bearing as tolerated. Surgical treatment is mandatory for unstable fractures.

Les fractures de la cheville représentent 10 % des fractures chez les adultes. Leur incidence est en augmentation, notamment en raison du vieillissement de la population. Les fractures malléolaires isolées en constituent les deux tiers. Les classifications les plus souvent utilisées sont celles anatomiques de Weber et de Lauge-Hansen. Le traitement des fractures de la malléole externe peut être conservateur ou chirurgical, selon la stabilité de la cheville. Pour tester la stabilité, une radiographie en charge est nécessaire. Si ce n'est pas possible le jour de traumatisme, un contrôle à 7 jours peut être organisé. Le traitement conservateur consiste en une immobilisation dans une attelle ou un plâtre en charge totale en fonction des douleurs pour six semaines. Le traitement chirurgical est réservé aux fractures instables.

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Purpose: This study aimed to evaluate the biomechanical response or load transfer on the osteoporotic L1 vertebra under torsional loading. Methods: To achieve this goal, a numerical model of osteoporotic vertebra in various trabecular bone degenerations was developed and tested. The mechanical behavior of the model was represented taking into account the anisotropic properties of the cancellous bone, which provided a more realistic mechanical picture of the biological subsystem. To ensure the reliability of osteoporotic degradation, the thinning of cortical bone and the appearance of gaps between trabecular bone and cortical bone were also taken into account when creating the models. Results: Finite element (FE) analysis showed that the deformations of cortical bone thinning and detachment of the cortical bone from the trabecular tissue lead to local instability of the vertebra. As a result, the cortical bone of a vertebra loses its load-bearing capacity, even if the strength limit is not reached. Conclusions: The results obtained allow us to state that taking into account the thinning of the trabeculae, which creates voids, is extremely important for load-bearing capacity of osteoporotic vertebrae. However, a limitation of this study is the lack of experimental data to ensure consistency with the computer simulation results.

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Purpose: Tendons adapt to loads applied to them, by changing their own mechanical properties. The purpose of the study was to examine the influence of practicing sport in the form of weightlifting/strength training by individuals of various age groups upon the mechanical properties of the patellar tendon. Methods: 200 people participated in the study. Group 1 (n = 109) comprised individuals training strength sports as amateurs, group 2 (n = 91) consisted of people who were not physically active. The patellar tendon was examined in various positions of the knee joint: 0, 30, 60, 90, 120° respectively. The following mechanical parameters were measured with the use of a device for myoto-nometric measurements, MyotonPRO: frequency [Hz], stiffness [N/m], decrement [log], relaxation time [ms] and creep [De]. The results were compared as regards physical activity, training history, BMI value, and gender. Results: Stiffness and tone increased while elasticity decreased with patellar tendon stretching degree. In the group of individuals in training, greater stiffness and tone and lower elasticity were noted. Moreover, stiffness and tone appeared to be higher in elderly people and individuals with longer training experience. Conclusions: Mechanical loads connected with strength training result in development of adaptive changes in the patellar tendon, in the form of higher stiffness and tone, as well as lower elasticity. The MyotonPRO device is useful for quantitative assessment of the mechanical properties of patellar tendon.

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INTRODUCTION: Adherence to wearing prescribed footwear is paramount in reducing the risk of developing diabetes-related foot ulcers, but adherence is often lower than optimal. This study aimed to investigate predictors of footwear adherence and variations in adherence and activity in people at risk of diabetes-related foot ulceration. METHODS: Sixty people at high foot ulcer risk were included. We measured the proportion of weight-bearing acitivity time the prescribed footwear was worn for seven days. Multiple linear regression and analysis of variance were used. RESULTS: Mean overall adherence was 63%. Adherence was lower at home than away from home (59% vs. 74%), while activity was higher at home (2.2 vs. 1.2 h/day). Adherence was similar across activities (61%-63%). No variable predicted the overall adherence. Higher Hba1c predicted lower adherence at home (ß = -0.34, p = 0.045, R2 = 11.6%). More daily steps predicted lower adherence away from home (ß = -0.30, p = 0.033, R2 = 9.3%). Adherence and activity were highest in mornings (71%, 1.1 h) and afternoons (71%, 1.5 h), and lower in evenings (40%, 0.8 h) and at nights (9%, 0.1 h). Adherence was similar on weekdays and weekend days (63% vs. 60%), but activity was higher on weekdays (3.4 vs. 3.0 h). CONCLUSION: Adherence levels and predictors thereof differed between adherence at home and away from home, so we suggest to treat them as different concepts. Due to the low explained variance, future studies should focus on other predictors such as psychological variables.

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Accentuated eccentric loading (AEL) involves higher load applied during the eccentric phase of a stretch-shortening cycle movement, followed by a sudden removal of load before the concentric phase. Previous studies suggest that AEL enhances human countermovement jump performance, however the mechanism is not fully understood. Here we explore whether isolating additional load during the countermovement is sufficient to increase ground reaction force, and hence elastic energy stored, at the start of the upward movement and whether this leads to increased jump height or power generation. We conducted a trunk-constrained vertical jump test on a custom-built device to isolate the effect of additional load while controlling for effects of squat depth, arm swing, and coordination. Twelve healthy, recreationally active adults (7 males, 5 females) performed maximal jumps without AEL, followed by randomised AEL conditions prescribed as a percentage of body mass (10%, 20%, and 30%), before repeating jumps without AEL. No significant changes in vertical ground reaction force at the turning point were observed. High load AEL conditions (20% and 30% body weight) led to slight reductions in jump height, primarily due to decreased hip joint and centre of mass work. AEL conditions did not alter peak or integrated activation levels of the knee extensor muscles. The constrained movement task used here, which excluded potential contributions of trunk motion, arm swing, rate of descent, squat depth, and point of load application, allows the conclusion that increased elastic energy return is not the primary mechanism for potentiating effects of AEL on jump performance.

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BACKGROUND: Running exposes the body to physiological and mechanical stresses that generate musculoskeletal injuries, such as low back pain due to large spinal loading. Increasing running cadence may reduce impact forces and spinal shrinkage. RESEARCH QUESTION: This study aimed to determine the relationship between spinal loading and running cadence. METHODS: This cross-sectional study included 15 runners from the local community (36 ± 11 years; 23 ± 2 kg.m-2, and 8 ± 9 years of running experience) who ran for 30 min (R30) and 60 min (R60) at a constant speed (10 km.h-1). The spinal loading was assessed via fine stature variation measurements before the run (baseline) at R30 and R60. Cadence was monitored via a wristwatch. The cadence ranged from 150 to 180 steps.min-1. A t-test was used to compare stature loss between R30 and R60 (relative to baseline), and a stepwise linear regression equation was used to identify the relationship between cadence and stature variation in each instant. RESULTS: There was a stature loss throughout the race (R30 = 5.27 ± 1.92 mm and R60 =7.51 ± 2.51 mm). A linear regression analysis revealed a negative relationship between stature loss and cadence, indicating that running at a faster cadence produces smaller spinal loading than running at slower cadences after R60 (R2 = 0.38; p<0.05). SIGNIFICANCE: Increasing running cadence might cause less spinal loading than running with a slower cadence, which may reduce the risk of injury and back disorders in runners.

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BACKGROUND: Despite deleterious biomechanics associated with injury, particularly as it pertains to load carriage, there is limited research on the association between physical demands and variables captured with wearable sensors. While inertial measurement units (IMUs) can be used as surrogate measures of ground reaction force (GRF) variables, it is unclear if these data are sensitive to military-specific task demands. RESEARCH QUESTION: Can wearable sensors characterise physical load and demands placed on individuals in different load, speed and grade conditions? METHODS: Data were collected on 20 individuals who were self-reportedly free from current injury, recreationally active, and capable of donning 23 kg in the form of a weighted vest. Each participant walked and ran on flat, uphill (+6 %) and downhill (-6 %) without and with load (23 kg). Data were collected synchronously from optical motion capture (OMC) and IMUs placed on the distal limb and the pelvis. Data from an 8-second window was used to generate a participant-based mean of OMC and IMU variables of interest. Repeated Measures ANOVA was used to measure main and interaction effects of load, speed, and grade. Simple linear regression was used to elucidate a relationship between OMC measures and estimated metabolic cost (EMC) to IMU measures. RESULTS: Load reduces foot and pelvic accelerations (p<0.001) but elevate signal attenuation per step (p=0.044). Conversely, attenuation per kilometre is lowered with the addition of load (p=0.017). Uphill had the lowest attenuation per step (p=0.003) and kilometre (p≤0.033) in walking, while downhill had the greatest attenuation per step (p≤0.002) and per kilometre (p≤0.004). Attenuation measures are inconsistently moderately related to limb negative work (R≤0.57). EMC is moderately positively related to unloaded running (R≥0.39), and moderately negatively related to walking with and without load (R≤-0.52). SIGNIFICANCE: While load reduces peak accelerations at both the pelvis and foot. However, it may increase demand on the lower extremity to attenuate the signal between the two sensors with each step, while attenuation over time reduces with load.

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Exercise with an unstable load is considered a new training method to activate the core muscles. Research has shown consistency regarding an unstable surface but has not provided comprehensive findings about the effect of an unstable load. The study aimed to examine the impact of an unstable load and unstable surfaces on core muscle activation and postural control during lifting. Thirty-eight participants lifted a load equivalent to 10 % of their body weight under three conditions: a stable load on an unstable surface, a stable load on a stable surface, and an unstable load on a stable surface. The center of pressure (COP) displacement and electromyography activity of abdominal and back extensor muscles were measured during lifting. The results indicated that lifting on an unstable surface activated the lumbar erector spinae and multifidus muscles more than in a stable condition (P<0.05). However, there was no significant difference in the level of thoracic erector spinae muscle activity between the unstable load and unstable surface conditions. The stable condition increased activity in the internal oblique muscle (1.37 times) compared to the unstable conditions. The analysis of postural control revealed that lifting the load on an unstable surface significantly decreased COP displacement in the anteroposterior direction (P<0.05), while holding the load on the unstable surface significantly increased COP displacement in the anteroposterior direction compared to the other conditions. These findings could be valuable for future rehabilitation research, learning appropriate lifting techniques, and setting specific training goals in sports.

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OBJECTIVE: The optimal treatment and rehabilitation strategy for acute Achilles tendon rupture (ATR) remain a debate. This study aimed to compare the results of the two postoperative regimens after treatment for ATR with modified closed percutaneous repair under local anesthesia. METHODS: In a 4-year study, 72 consecutive patients with acute complete ATR were randomized after percutaneous repair into a functional group (FG), using a modified brace (28 males, three females; mean age 41.9 [29-71] years) and an immobilization group (IG), wearing a rigid plaster (28 males, two females; mean age 42.2 [29-57] years), for a period of 6 weeks. Except for immobilization, they followed the same weight-bearing and rehabilitation protocols. The follow-up period was 3 years. The complication rate, active and passive ankle range of motion, standing heel-rise test, clinical outcome using the American Foot and Ankle Society (AOFAS) hindfoot-ankle score, return to the previous activity level, and subjective assessment were assessed. RESULTS: There was one rerupture in the IG and two transient sural nerve disturbances in the FG and one in the IG, and one suture extrusion in the IG, with no other complications. The average AOFAS scores were 96.9 ± 4.3 and 96.0 ± 4.9 in the FG and IG, respectively. Patients in the FG reached a final range of motion and muscular strength sooner without limping and were more satisfied with the treatment. No significant differences could be detected between groups according to the results in any of the assessed parameters. CONCLUSION: Early dynamic functional bracing in patients with ATR treated with modified closed percutaneous repair under local anesthesia resulted in earlier functional recovery with similar final results in terms of complications and functional outcomes, such as rigid postoperative immobilization with standardized rehabilitation and weight-bearing protocol. LEVEL OF EVIDENCE: I, Prospective randomized study.

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BACKGROUND: Data are lacking as to when a meniscal allograft transplant (MAT) may be biomechanically superior to a partially resected lateral meniscus. HYPOTHESIS: Lateral MAT using a bone bridge technique would restore load distribution and contact pressures in the tibiofemoral joint to levels superior to those of a partial lateral meniscectomy. STUDY DESIGN: Controlled laboratory study. METHODS: Eleven fresh-frozen human cadaveric knees were evaluated in 5 lateral meniscal testing conditions (native, one-third posterior horn meniscectomy, two-thirds posterior horn meniscectomy, total meniscectomy, MAT) at 3 flexion angles (0°, 30°, and 60°) under a 1600-N axial load. Pressure sensors were used to acquire contact pressure, contact area, and peak contact pressure within the tibiofemoral joint. RESULTS: Limited (one-third and two-thirds) partial lateral posterior horn meniscectomy showed no significant increase in mean and peak contact pressures as well as no significant decrease in contact area compared with the intact state. Total meniscectomy significantly increased mean contact pressure at 0° and 30° (P = .008 and P < .001, respectively), increased peak contact pressure at 30° (P = .04), and decreased mean contact area in all flexion angles compared with the native condition (P < .01). Lateral MAT significantly improved mean contact pressure compared with total meniscectomy at 0° and 30° (P = .002 and P = .003, respectively) and increased contact area at 30° and 60° (P = .003 and P = .009, respectively), although contact area was still significantly smaller (24.1%) after MAT relative to the native meniscus (P = 0.015). However, allograft transplant did not result in better tibiofemoral contact biomechanics compared with limited partial meniscectomy (P > .05). CONCLUSION: The peripheral portion of the lateral meniscus provided the most important contribution to the distribution of contact pressure across the tibiofemoral joint in the cadaveric model. Total meniscectomy significantly increased mean and peak contact pressure in the cadaveric model and decreased contact area. Lateral MAT restored contact biomechanics close to normal but was not superior to the partially meniscectomized status. CLINICAL RELEVANCE: Surgeons should attempt to preserve a peripheral rim of the posterior lateral meniscus. Meniscal allograft transplant appears to improve but not normalize mean contact pressure and contact area relative to total lateral meniscectomy.

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The aim of the present study was to examine the effects of attentional focus instructions on acute changes in the transverse relaxation time (T2) of the femorotibial cartilage and in cartilage volume during repeated drop-jump landings. Ten healthy females (Mage = 20.4 ± 0.8 years) performed a drop landing task from a 50 cm high box over the course of 3 days (50 repetitions each day) across three attentional focus conditions: external focus (EF: focus on landing as soft as possible), internal focus (IF: focus on bending your knees when you land), and control (CON: no-focus instruction), which was counterbalanced across focus conditions. T2 mapping and the volume of femorotibial cartilage were determined from magnetic resonance imaging scans at 1.5 T for the dominant knee before and after completing the drop landings in each attentional focus condition per day. Results indicated a smaller change in cartilage T2 relaxation time and volumetry in the central load-bearing lateral cartilage under the EF, compared to IF and CON. Moreover, the change in T2 and cartilage volume was greater for lateral tibial cartilage as compared to femoral cartilage and was independent of attentional focus instructions. No significant acute quantitative changes were observed in the medial compartment. The peak vertical ground reaction force was found to be the lowest under the EF, compared to IF and CON. These findings suggest that external focus of attention may reduce cartilage load, potentially aiding in the control or management of cartilage injuries during landing in female athletes.

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INTRODUCTION: Clinical investigations have attributed lumbar spine injuries in combat to the vertical vector. Injury prevention strategies include the determination of spine biomechanics under this vector and developing/evaluating physical devices for use in live fire and evaluation-type tests to enhance Warfighter safety. While biological models have replicated theater injuries in the laboratory, matched-pair tests with physical devices are needed for standardized tests. The objective of this investigation is to determine the responses of the widely used Hybrid III lumbar spine under the vertical impact-loading vector. MATERIALS AND METHODS: Our custom vertical accelerator device was used in the study. The manikin spinal column was mounted between the inferior and superior six-axis load cells, and the impact was delivered to the inferior end. The first group of tests consisted of matched-pair repeatability tests, second group consisted of adding matched-pair tests to this first group to determine the response characteristics, and the third group consisted of repeating the earlier two groups by changing the effective torso mass from 12 to 16 kg. Peak axial, shear, and resultant forces at the two ends of the spine were obtained. RESULTS: The first group of 12 repeatability tests showed that the mean difference in the axial force between two tests at the same velocity across the entire range of inputs was <3% at both ends. In the second group, at the inferior end, the axial and shear forces ranged from 4.9-25.2 kN to 0.7-3.0 kN. Shear forces accounted for a mean of 11 ± 6% and 12 ± 4% of axial forces at the two ends. In the third group of tests with increased torso mass, repeatability tests showed that the mean difference in the axial force between the two tests at the same velocity across the entire range of inputs was <2% at both ends. At the inferior end, the axial and shear forces ranged from 5.7-28.7 kN to 0.6-3.4 kN. Shear forces accounted for a mean of 11 ± 8% and 9 ± 3% of axial forces across all tests at the inferior and superior ends. Other data including plots of axial and shear forces at the superior and inferior ends across tested velocities of the spine are given in the paper. CONCLUSIONS: The Hybrid III lumbar spine when subjected to vertical impact simulating underbody blast levels showed that the impact is transmitted via the axial loading mechanism. This finding paralleled the results of axial force predominance over shear forces and axial loading injuries to human spines. Axial forces increased with increasing velocity suggesting the possibility of developing injury assessment risk curves, i.e., the manikin spine does not saturate, and its response is not a step function. It is possible to associate probability values for different force magnitudes. A similar conclusion was found to be true for both magnitudes of added effective torso mass at the superior end of the manikin spinal column. Additional matched-pair tests are needed to develop injury criteria for the Hybrid III male and female lumbar spines.

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Chondrocytes respond to mechanical stimuli by increasing their intracellular calcium concentration. The response depends on the cellular environment. Previous studies have investigated chondrocytes under slow strain rates or cells embedded in hydrogels, but the response of chondrocytes in their native environment under physiologically relevant cyclic loads and dynamic hydrostatic pressure has not been studied. This study investigated the calcium signaling response of in-situ chondrocytes under physiological cyclic compressive loads and hydrostatic pressure with varying frequency and load rates. Bovine cartilage explants were stained with a fluorescent calcium indicator dye and subjected to physiologically relevant cyclic loads using a custom-built loading device secured on a confocal/multiphoton microscope. Calcium fluorescence intensities of the cells were tracked and analyzed. Loading groups were compared using one-way ANOVA followed by a post-hoc test with Tukey correction (α = 0.05). The percentage of cells signaling increased in all compressive loading conditions compared to the no-load baseline. The percentage of cells responding under 1 Hz load was significantly greater than the slow ramp and 0.1 Hz group (p < 0.05). The number of compression cycles had no effect on the calcium signaling response (p > 0.05). The width and time between consecutive peaks were not different between different loading conditions (p > 0.05). Calcium signaling of in-situ chondrocytes did not increase under dynamic hydrostatic pressure of magnitudes up to 0.2 MPa at frequencies of 0.5 Hz and 0.05 Hz (p > 0.05). In conclusion, in-situ chondrocytes respond to physiological compressive loads in a strain rate-dependent manner with an increased number of responsive cells and unaltered temporal characteristics.

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BACKGROUND: Pressure offloading is a critical component of plantar foot ulcer management, including diabetes-related foot ulcers (DFU). Conventional offloading options such as total contact casting and removable knee-high walkers may be unsuitable or unsuccessful in patients with morbid obesity, intermittent lower limb oedema, high exudative wounds or poor mobility. A mouldable fibreglass backslab device (BSD) may be a practical alternative to be considered in these situations. METHODS: Data were retrospectively collected on 28 patients (29 foot ulcers) with non-healing ulcers who received a BSD to offload their foot ulcer as an extension to standard offloading care. Baseline data included: patient demographics, type of offloading prior to BSD application, date of ulcer onset, days ulcer present prior to BSD application and ulcer size at BSD initiation. Measures of success included ulcer size reduction 12 weeks post-BSD application, time to complete ulcer healing in BSD, time to 50% reduction in ulcer size post-BSD application and total number of days ulcer present. RESULTS: The median (IQR) ulcer area and ulcer duration at baseline for 19 patients (20 ulcers) who used the BSD was 1.65 (0.4-3.8) cm2 and 531 (101-635) days. At 12 weeks, the median (IQR) ulcer area was 0.3 (0-0.55) cm2 with a median (IQR) reduction of 97 (80-100) %. Nine (45%) ulcers achieved complete wound healing (100% reduction in wound size) at 12 weeks post-BSD application, and the remaining 11 (55%) ulcers achieved at least 50% reduction in wound size. The median (IQR) time to complete wound healing and 50% reduction in wound size was 71 (35-134) days and 24 (15-44) days, respectively. Nine patients ceased use of the BSD and reverted to conventional offloading before their wounds had healed. Of these, four patients achieved a 50% reduction in wound size at the 12-week mark with conventional offloading. CONCLUSION: Our preliminary data suggests that a mouldable fibreglass BSD may be a practical offloading option in the management of DFUs, especially when conventional offloading methods are unsuccessful, unsuitable or unacceptable to patients. Higher level evidence is required to demonstrate suitability or efficacy of the BSD compared to current evidence-based recommended offloading methods.

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Background: Increased load bearing across the patellofemoral and tibiofemoral articulations has been associated with total knee arthroplasty (TKA) complications. Therefore, the purpose of this study was to quantify the biomechanical characteristics of the patellofemoral and tibiofemoral joints and simulate varying weight-bearing demands after posterior cruciate ligament-retaining (CR) and posterior-stabilized (PS) TKAs. Methods: Eight fresh-frozen cadaveric knees (average age, 68.4 years; range, 40-86 years) were tested using a custom knee system with muscle-loading capabilities. The TKA knees were tested with a CR and then a PS TKA implant and were loaded at 6 different flexion angles from 15° to 90° with progressively increasing loads. The independent variables were the implant types (CR and PS TKA), progressively increased loading, and knee flexion angle (KFA). The dependent variables were the patellofemoral and tibiofemoral kinematics and contact characteristics. Results: The results showed that at higher KFAs, the position of the femur translated significantly more posterior in CR implants than in PS implants (36.6 ± 5.2 mm and 32.5 ± 5.7 mm, respectively). The patellofemoral contact force and contact area were significantly greater in PS than in CR implants at higher KFAs and loads (102.4 ± 12.5 N and 88.1 ± 10.9 N, respectively). Lastly, the tibiofemoral contact force was significantly greater in the CR than the PS implant at flexion angles of 45°, 60°, 75°, and 90° KFA, the average at these flexion angles for all loads tested being 246.1 ± 42.1 N and 192.8 ± 54.8 N for CR and PS implants, respectively. Conclusions: In this biomechanical study, CR TKAs showed less patellofemoral contact force, but more tibiofemoral contact force than PS TKAs. For higher loads across the joint and at increased flexion angles, there was significantly more posterior femur translation in the CR design with a preserved posterior cruciate ligament and therefore significantly less patellofemoral contact area and force than in the PS design. The different effects of loading on implants are an important consideration for physicians as patients with higher load demands should consider the significantly greater patellofemoral contact force and area of the PS over the CR design.

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BACKGROUND: Prefabricated orthotic insoles are widely commercially available for self-selection to treat foot and lower-body musculoskeletal pain, without requiring advice from health care professionals. Although they are generally designed to mimic traditional design features of custom-made orthotics used in clinical practice, the effects of prefabricated insoles on plantar pressure distribution are poorly understood. OBJECTIVE: This investigation aimed to evaluate and directly compare the effects of a range of 6 different commercially available prefabricated orthotic insole designs on plantar pressure in healthy individuals. METHODS: This was a single-center, randomized, open-label, crossover investigation. In-shoe dynamic pressure (F-scan) was investigated in 24 healthy subjects with normal foot posture, wearing standard shoes alone and in combination with 6 different orthotic insoles, consecutively, measured on a single day. The biomechanical impact of each insole was determined by the statistical significance of changes from baseline measurements (standard shoe alone). RESULTS: Insoles with heel cups and medial arch geometries consistently increased contact area at medial arch and whole-foot regions and reduced both plantar peak pressure (PP) and pressure time integral at medial arch and heel regions. CONCLUSIONS: This investigation has aided in further understanding the mode of action of prefabricated insoles in a healthy population. The insoles in this study redistributed plantar pressure at key regions of the foot, based on design features common to prefabricated insoles. Prefabricated orthotic insoles represent an easily accessible means of reducing lower-body musculoskeletal stress for those who spend prolonged periods of time on their feet.

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Hoof care providers are pivotal for implementing biomechanical optimizations of the musculoskeletal system in the horse. Regular visits allow for the collection of longitudinal, quantitative information ("normal ranges"). Changes in movement symmetry, e.g., after shoeing, are indicative of alterations in weight-bearing and push-off force production. Ten Warmblood show jumping horses (7-13 years; 7 geldings, 3 mares) underwent forelimb re-shoeing with rolled rocker shoes, one limb at a time ("limb-by-limb"). Movement symmetry was measured with inertial sensors attached to the head, withers, and pelvis during straight-line trot and lunging. Normalized differences pre/post re-shoeing were compared to published test-retest repeatability values. Mixed-model analysis with random factors horse and limb within horse and fixed factors surface and exercise direction evaluated movement symmetry changes (p < 0.05, Bonferroni correction). Withers movement indicated increased forelimb push-off with the re-shod limb on the inside of the circle and reduced weight-bearing with the re-shod limb and the ipsilateral hind limb on hard ground compared to soft ground. Movement symmetry measurements indicate that a rolled rocker shoe allows for increased push-off on soft ground in trot in a circle. Similar studies should study different types of shoes for improved practically relevant knowledge about shoeing mechanics, working towards evidence-based preventative shoeing.

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