Introduction

Delayed onset muscle soreness (DOMS) in the quadriceps is frequent in runners finishing a marathon race, and may result in several days of discomfort and pain. There is an increasing clinical evidence that noninvasive, pulsed electromagnetic field therapy (PEMF) can have physiological effect on inflammation and tissue repair. The purpose of this pilot study was to investigate the effect of PEMF on quadriceps muscle soreness in marathon runners and to use the data to calculate an appropriate sample size for a subsequent study.

Background: Heterotopic ossification is a common feature that follows total hip arthroplasty, and affects up to 70% of patients with clinical implications, such as pain and restricted hip movements. Previous clinical observation showed negligible heterotopic ossification in our patients who underwent total hip arthroplasty due to familial Mediterranean fever, and received colchicines on a daily basis. Aims: To evaluate in vitro, in vivo and during clinical studies whether colchicines, given on a prophylactic daily basis to all total hip arthroplasty patients, was responsible for the negligible heterotopic ossification. Methods: In vitro: cell lines of fibroblasts and osteoblasts were cultured with increasing concentrations of colchicines. Direct cell counts [3H]thymidine uptake, and mineralization were measure. In vivo: heterotopic ossification was induced in the thigh muscle of rabbits by injecting bone marrow. Animals were given colchicines, and X-ray radiographs, ultrasound the histological studies measured its effect on heterotopic ossification. Clinical study: Fifty-two patients admitted for total hip arthroplasty were randomly selected to receive colchicines on a daily basis, starting 10 days pre-operatively, and 6 weeks postoperatively. Clinical evaluation was made according to Harris Hip Score and heterotopic ossification according to Brooker classification. Results: In vitro: colchicines was found to be a strong, nonselective inhibitor of cell proliferation, and an even greater inhibitor of tissue mineralization. In vivo: statistically significant reduction in the amount of hetero-topic ossification induced in the thigh muscle of rabbits was measured in the groups that received colchicines. Clinical study: Patients who received colchicines pre-operatively developed a negligible amount of hetero-topic ossification after total hip arthroplasty at 1-year follow-up without adversely affecting the Harris Hip Score. Conclusions: Colchicine is a strong inhibitor of cell proliferation and tissue mineralization, and an effective means of reducing heterotopic ossification after total hip arthroplasty. These effects may be used in other bone-forming processes: after hip/pelvic trauma, head injury, and possibly in other bone-forming conditions

There are nearly no studies which describe the influence of the ileotibial tract (IT) on force distribution in the knee joint in a qunatitative manner. Therfore the aim of this work was to develop a complex 3-D computer model of the lower extremity, consisting of bones, joints and muscle models describing their dynamic behaviour including a special IT model. The computer model provided the possibility to simlate training of the muscular system. Thus the computer model provided among others the possibility to simulate training of the lateral thigh muscles and vastus lateralis with the aim to tension the IT, with the option to calculate force distribution in the knee and compare it with the effect of a tibial osteotomy. Patients with varus knees were examined. Kinematic data during walking together with forceplate and EMG data wer collected, before and after tibial osteotomy. The anatomy of the patients was recorded by MRI. Gait and MRI data were the input in the new developed three dimensional computer model. The scaled geometrical data by Delp (1990) and the MRI data were combined to represent the individuals anatomy. The model of the lower extremity included 43 muscles with origins/insertions and force-length properties described by Delp (1990). The muscle model was improved by including force-velocity properties and a new muscle tendon parameter (tendon stiffness). A functional scaling method was developed to fit the muscle models to individual anatomy. The IT complex was modelled as a coupled unit of IT, tensor fascia latae and gluteus maximus. Muscle and joint forces were determined using an optimization approach minimizing the cube of the sum of muscle forces divided by their upper bounds. Simulated muscle training of the lateral thigh muscles and vastus lateralis led to an increased tensioning of the IT. As a result the lateral knee force raised considerably similar to the increase after osteotomy. However the decrease in the medial compartment was small and not comparable with the effect of a valgus osteotomy. Tensioning of the IT leads apparently to an overall larger resulting knee force stabilizing the joint, but is not able to reduce medial knee force to an extent that can avoid osteotomy

Significance. Acute compartment syndrome (ACS) occurs after muscle injury and is characterised by increased pressure in the muscle compartment that can result in devastating complications if not diagnosed and treated appropriately. ACS is currently confirmed by repeated needle sticks to measure the compartment pressure using a hand-held compartment pressure monitor. This approach is often not reproducible and is not appropriate for continuous monitoring. To address the shortcomings of currently available technology we are developing an implantable micro-device that will measure compartment pressure directly and continuously over the 24 hours critical period following injury using a radio frequency identification (RFID) platform integrated with a MEMS capacitive pressure sensor. Methods. The prototype implantable device measuring 3mmx3mm consists of a capacitive pressure sensor, a sensor readout circuitry, an antenna and a radio frequency reader. A prototype sensor was packaged in Silicone gel (MED-6640, Nusil Technology LLC) for ex vivo and in vivo testing in three compartment models. First, it was tested ex vivo in an airtight vessel using a blood pressure monitor to pump air and increase the pressure inside the vessel. Second, it was implanted in a muscle compartment of a fresh porcine hind limb and an infusion pump with normal saline was used to raise the tissue pressure. Third, it was implanted in the posterior thigh muscle of a rat where the pressure was increased by applying a tourniquet around the thigh. The readings were compared with those from a hand-held Stryker Intra-compartmental Pressure Monitor System used in the trauma room. Results. The sensor reading from the radio frequency reader software interface in all three models showed good linearity against the pressure applied to the compartment. Conclusion. The successful completion of this project will lead to the development of an implantable miniaturised wireless pressure sensor microsystem capable of measuring tissue compartment pressures in the critical period after traumatic injury and reduce the incidence of serious complications such as severe pain, paralysis, sensory deficits, muscle necrosis and permanent disability

Purpose of the study: Echinococcosis is an anthropozoonosis with a predominantly muscular, more rarely osteoarticular, localisation. The purpose of this work was to describe the conditions of discovery, the diagnostic management, the serology and pathology findings, and the results of surgical treatment as well as potential complications. Material and methods: We collected over a 16-year period, 14 cysts in eight women and six men. Mean age was 39 years (range 17–75) and delay to consultation was 36 months. The patients had an ultrasound (all 14 cases), computed tomography (n=7), MRI (n=7), hydatid serology (n=9) and pathology examination (n=10). All patients were treated surgically (7 complete resection); one patient was given associated medical treatment for a multiple localisation. Results: Muscle hydatisosis occurred in all cases as a medium-sized tumour (mean 9 cm, range 5–16 cm) which was painful in half of the cases. One cyst was superinfected and one patient had a neurological complication. The most common site was the adductor compartment of the thigh (5 cases). Four patients had an associated visceral localization. At mean 4 years follow-up, one patient had a superinfection and two others recurrence at 7 and 10 months, with surgical revision and good outcome. Discussion: The risk vascularisation of the thigh muscles explains these localisations. Ultrasound is a sensitive exploration which suggests the diagnosis in all cases. CT and MRI confirm the diagnosis and define the cyst relations. Pathology is needed for formal diagnosis. Total pericystectomy or wide resection is the best surgical technique, although not always readily achieved. Conclusion: Muscle hydatidosis is rare. Treatment is surgical, different from the osteoarticular localisation, similar to the visceral foci. Recurrence is exceptional. Prevention remains the best treatment

Introduction Following any intraarticular fracture, joint range of movement and muscle strength recovery are vital factors in patient’s return to activities. Quadriceps weakness is a known complication of any injury affecting the knee. The purpose of this study was to investigate the recovery of knee ROM and quadriceps and hamstrings muscle strength in the first year after tibial plateau fracture and to assess factors that affect the recovery. Method 63 patients were recruited over a 5-year period. Data regarding the age and sex of the patient, the mechanism of injury, the grade of the fracture according to Shatzker’s classification and the treatment received were recorded. All patients underwent a standard rehabilitation regime. At 3, 6 and 12 months after injury the patients were seen by a research physiotherapist. The range of movement was recorded. Thigh muscle peak torque was measured using isokinetic dynanmometry. The uninjured limb was used as the control – the peak torque in the injured limb was expressed as a percentage of the value in the uninjured limb to give the percentage recovery in the injured limb. Results There was an initial extension deficit of 7° at 3 months, which improved to 3° at 12 months. Quadriceps strength recovery lagged behind that in the hamstrings at all times and only achieved only 77% at 12 months, compared to 90% in the hamstrings (p< 0.001). Patients under 40 outperformed those over 40 at each time point. At 12 months under 40s had achieved 85% recovery in their quadriceps, while over 40s only reached 74% (p< 0.01). Patient sex, mechanism of injury and grade of fracture had no effect on the level of recovery in this study. Conclusion Patients who sustain a tibial plateau fracture have a residual small extension deficit and objective quadriceps weakness at 1 year post injury. Patient age has a significant effect on the level of quadriceps recovery. This information is useful when counselling patients who sustain these injuries

Purpose: The aim of this study was to investigate the results of end-to-side neurorraphy of the common peroneal nerve (CPN) to the tibial nerve (TN) in rats, after administration of bFGF or NGF. Materials: Five (5) groups of adult male Wistar rats, each comprising 25 animals, were studied:. End-to-side neurorraphy (4 groups) Group A bFGF (20ng) Group B NGF (25ng) Group C (normal saline) Group X [bFGF (20ng) + NGF (25ng)]. Negative control group (G) Animal keeping was conform to standard conditions set by the NIH (appropriate cages for housing; standard rat chow and water ad libitum; 12h – light/darkness exposure). All experimental procedures were performed under the supervision of a veterinarian and were prospectively approved by the Animal Experimental Ethics Committee. Methods: In groups A, B and X, the CPN was sharply divided at a distance of 7mm distal to its origin from the rat sciatic nerve; the proximal CPN stump was then sutured into the thigh muscles, whereas the distal CPN stump was sutured terminolaterally to the ipsilateral TN. Sub sequently, a total volume of fifty microliters (50μl) of the corresponding solution of growth factor(s) was administered in each case beneath the epineurium, proximal to the CPN/TN coaptation site, with the aid of a microsyringe. The same surgical procedure was carried out in group C (positive control group), as well, but an equal volume (i.e. 50μl) of normal saline was administered instead. Finally, in each of the animals of the remaining group G, both the proximal and the distal stump of the CPN were carefully sutured into the neighbouring muscles; hence, the latter would constitute a negative control group, thanks to the resulting atrophy of the CPN – innervated musculature. All surgical procedures took place with the animals under dissociative anaesthesia and were performed under sterile conditions, using the operating microscope and applying microsurgical techniques. In each case, the right CPN was operated upon; the contralateral (left) CPN remained intact, thus serving as control. Euthanasia was achieved by means of intracardiac administration of high – dose sodium pentobarbital. Results: The evaluation of the outcome four (4) months postoperatively was based on clinical examination, walking-track analysis, electromyographic and histomorphometric studies. Our data indicate that the administration of the growth factors under investigation has a favorable effect on the outcome of CPN repair; the administration of bFGF, in particular, seems to improve the results of terminolateral neurorraphy in the time span studied. Conclusions: In rats, CPN repair via end-to-side neurorraphy to the TN can be enhanced by the administration of bFGF or NGF

Since the time of Charles Darwin, it is known that three principles of regeneration explain the similarity of neo-formed tissues, the dependence of regeneration rhythm on age and the position of the animal in the evolutionary chain. The latter principle is know as the Weisman-Pschibram principle. Regeneration depends on several factors: level of tissue specialisation and differentiation, tissue resistance to hypoxia, and other manifestations of generally recognised biological regulation. According to a fourth principle, the regenerative potential of different parts of the body depend on a cranio-caudal gradient which rhythms their postnatal growth and development. Distinction of this principle is of importance because of its practical applications. Experience with increasing the height of persons with achrondroplasty by lengthening different limb segments reveals that the femur has less regeneration potential despite its long length. Leg lengthening is preferred; saving muscle function, there is a 20% potential for lengthening. Male subjects are generally considered to be short in height when there is a 10% growth retardation of the longitudinal dimension of the body. In female subjects, generative function is considered deficient if the length of the trunk is less than 73 cm. Using these criteria, experience has shown that leg malformations are not observed in subjects with a 10% growth retardation of the limb. The rate of growth retardation has to reach 40% before growth ceases. The relative moment of posterior leg muscle force increases with increasing leg length (F = 0.063 x L – 0.7; r=0.965, n=123). With a 10% growth deficit, the leg lengthening operation limits the amplitude of ankle movement 15% on average. With the same 10% growth deficit, lengthening the femur with the same technique decreases the amplitude of knee movement 22%. It has been noted that a 40% decrease in leg muscle force after leg lengthening does not affect locomotor function. The same decrease in thigh muscles after femur lengthening alters function. Like the first three principles, the fourth has its exceptions. It is important however to distinguish the influence of biological factors from other, for example technical, factors. Thus orthopaedic surgeons prefer the humerus for lengthening the upper limb, but this results from the difficulty in preserving rotation movements when lengthening the forearm. The important advances obtained in recent years in patients with bony defects of the hand and foot are further arguments clearly in favour of the existence of a cranio-caudal gradient in regenerative potential of the limbs

Aims

We aimed to evaluate the utility of ⁶⁸Ga-citrate positron emission tomography (PET)/CT in the differentiation of periprosthetic joint infection (PJI) and aseptic loosening (AL), and compare it with ^99mTc-methylene bisphosphonates (^99mTc-MDP) bone scan.

Introduction. Most of patients with unilateral hip disease shows muscle volume atrophy of pelvis and thigh in the affected side because of pain and disuse, resulting in reduced muscle weakness and limping. However, it is unclear how the muscle atrophy correlated with muscle strength in the patient with hip disorders. A previous study have demonstrated that the volume of the gluteus medius correlated with the muscle strength by volumetric measurement using 3 dimensional computed tomography (3D-CT) data, however, muscles influence each other during motions and there is no reports focusing on the relationship between some major muscles of pelvis and thigh including gluteus maximus, gluteus medius, iliopsoas and quadriceps and muscle strength in several hip and knee motions. Therefore, the purpose of the present study is to evaluate the relationship between muscle volumetric atrophy of major muscles of pelvis and thigh and muscle strength in flexion, extension and abduction of hip joints and extension of knee joint before surgery in patients with unilateral hip disease. Material and Methods. The subjects were 38 patients with unilateral hip osteoarthritis, who underwent hip joint surgery. They all underwent preoperative computed tomography (CT) for preoperative planning. There were 6 males and 32 females with average age 59.5 years old. Before surgery, isometric muscle strength in hip flexion, hip extension, hip abduction and knee extension were measured using a hand held dynamometer (µTas F-1, ANIMA Japan). Major muscles including gluteus maximus, gluteus medius, iliopsoas and quadriceps were automatically extracted from the preoperative CT using convolutional neural networks (CNN) and were corrected manually by the experienced surgeon. The muscle volumetric atrophy ratio was defined as the ratio of muscle volume of the affected side to that of the unaffected side. The muscle weakness ratio was defined as the ratio of muscle strength of the affected side to that of the unaffected side. The correlation coefficient between the muscle atrophy ratio and the muscle weakness ratio of each muscle were calculated. Results. The average muscle atrophy ratio was 84.5% (63.5%–108.2%) in gluteus maximus, 86.6% (65.5%–112.1%) in gluteus medius, 81.0% (22.1%–130.8%) in psoas major, and 91.0% (63.8%–127.0%) in quadriceps. The average muscle strength ratio was 71.5% (0%–137.5%) in hip flexion, 88.1% (18.8%–169.6%) in hip abduction, 78.6% (21.9%–130.1%) in hip extension and 84.3% (13.1%–122.8%) in knee extension. The correlation coefficient between the muscle atrophy and the ratio of each muscle strength between the affected and unaffected side were shown in Table 1. Conclusion. In conclusion, the muscle atrophy of gluteus medius muscle, psoas major muscle and quadriceps muscle significantly correlated with the muscle weakness in hip flexion. The muscle atrophy of psoas major muscle and quadriceps muscle also significantly correlated with the muscle weakness in knee extension. There were no significant correlation between the muscle atrophy and the muscle weakness in hip extension and abduction

Aims

Dystrophic calcification (DC) is the abnormal appearance of calcified deposits in degenerating tissue, often associated with injury. Extensive DC can lead to heterotopic ossification (HO), a pathological condition of ectopic bone formation. The highest rate of HO was found in combat-related blast injuries, a polytrauma condition with severe muscle injury. It has been noted that the incidence of HO significantly increased in the residual limbs of combat-injured patients if the final amputation was performed within the zone of injury compared to that which was proximal to the zone of injury. While aggressive limb salvage strategies may maximize the function of the residual limb, they may increase the possibility of retaining non-viable muscle tissue inside the body. In this study, we hypothesized that residual dead muscle tissue at the zone of injury could promote HO formation.

Thigh-calf contact force is the force acting on posterior side of the thigh and calf during deep knee flexion. It has been reported the force is important to analyze the kinetics of a lower limb and a knee joint. Some previous researches reported the measured thigh-calf contact force, however, the values varied among the reports. Furthermore, the reports indicated that there were large variations even in a single report. One of the reports tried to find the relationship between the magnitude of thigh-calf contact force and anthropometric measurement as height, weight or perimeter of the lower limb, however, there could not found clear correlations. We considered that the cause of the variations might be the difference of the posture. At heel-rise squatting posture, we can bend or stand upright the upper body. Therefore we tried to create the equation to estimate the thigh-calf contact force by multiple regression analysis, using the anthropometric and posture parameters as explanatory variables. We performed the experiment to measure thigh-calf contact force, joint angles and anthropometric information. Test subjects were 10 healthy male. First we measured their height, weight, perimeter of the thigh and muscle mass of the legs and whole body. Muscle mass was measured by body composition meter (BC-118E, Tanita Co., Japan). Then, test subjects were asked to squat with their heels lifted and with putting the pressure distribution sensor between thigh and calf. And they bent their upper body forward and backward. The pressure sensor to be used was ConfroMat System (Nitta Co., Japan). After that, we measured the joint angles of the hip, knee and ankle, and the angle between the floor and upper body using the videos taken during the experiment. Then, we created the equation to estimate the thigh-calf contact force by linear combination of the anthropometric values and joint angles. The coefficients were settled as to minimize the average error between measured and estimated values. Results are shown in Fig.1. Forces were normalized by the body weight of the test subjects. Because the horizontal axes show the measured and vertical axis show the estimated values, the estimation is accurate when the plots are near the 45-degree line. Average error was 0.11BW by using only physical values, 0.15BW by angles and 0.06BW using both values. And the maximum error was 0.69BW, 0.43BW and 0.32BW respectively. Thus we could estimate the thigh-calf contact force by multiple regressions, using both physical parameters and angles to indicate the posture. Using the equation, we would be able to analyze the kinetics of a lower limb by physical and motion measurement. Our future work might be increasing the number of subjects to consider the appropriateness, because the test subjects of this study were very limited

Objectives

Legg–Calvé–Perthes’ disease (LCP) is an idiopathic osteonecrosis of the femoral head that is most common in children between four and eight years old. The factors that lead to the onset of LCP are still unclear; however, it is believed that interruption of the blood supply to the developing epiphysis is an important factor in the development of the condition.