To determine the influence of rotator cuff muscle activity on humeral head migration relative to glenoid during active arm elevation we studied five fresh cadaveric shoulders. The shoulder girdles were mounted in an apparatus that simulated contraction deltoid and muscles while maintaining normal scapulothoracic relationship. arms abducted using four different configurations activity: alone; supraspinatus; deltoid, infraspinatus, teres minor, subscapularis; supraspinatus, subscapularis. For...

Background: The plantar aponeurosis is known to be a major contributor arch support, but its role in transferring Achilles tendon loads the forefoot remains poorly understood. goal of this study was increase our understanding function during gait. We specifically examined force pattern and relationship forces simulations stance phase gait cadaver model. Methods: Walking were performed with seven feet. movements foot ground reaction reproduced by prescribing kinematics proximal part tibia...

Emerging evidence suggests that connexin mediated gap junctional intercellular communication contributes to many aspects of bone biology including development, maintenance homeostasis and responsiveness cells diverse extracellular signals. Deletion 43, the predominant junction protein in bone, is embryonic lethal making it challenging examine role 43 vivo. However, transgenic murine models which only osteocytes osteoblasts are deficient fully viable, have recently been developed....

We performed a biomechanical study of seventeen hip joints in the pelves nine cadavera order to assess role that acetabular labrum and transverse ligament play load transmission. The distribution contact area pressure between acetabulum femoral head was measured with four different conditions: intact (seventeen hips), after removal (eight entire (nine both hips). joint loaded simulated single-limb stance, measurements were made use pressure-sensitive film.A peripheral seen acetabula. This...

The long-term success of massive osteochondral allografts depends not only on the incorporation transplanted articular cartilage. Osteochondral are immunogenic, and, once an immune response is stimulated by exposure to donor cellular antigens, cartilage becomes vulnerable direct injury cytotoxic antibodies or lymphocytes, indirect inflammatory mediators and enzymes induced response. To clarify role histocompatibility antigen-matching health cartilage, we orthotopically implanted canine...

Background: Stress fractures of the metatarsals are common overuse injuries in athletes and military cadets, yet their etiology remains unclear. In vitro, high bone strains have been associated with accumulation microdamage shortened fatigue life. It is therefore postulated that stress vivo caused by elevated strains, which lead to excessive damage. We used a cadaver model test hypothesis increase simulated muscle plantar fasciotomy.Methods: A dynamic gait simulator was load fifteen...

Abstract The function of the infraspinatus, teres minor, and subscapularis during elevation arm remains poorly defined. These muscles may generate moments that contribute to abduction arm, although they frequently are classified as humeral depressors. purposes this study were measure contributions made by more inferiorly positioned rotator cuff relative supraspinatus determine range motion at which most effective. Five fresh cadaveric shoulder girdles mounted in an apparatus designed...

The purpose of this study is to elucidate anatomically the, atlantoaxial transarticular screw fixation described by Magerl in 1979 and compare it biomechanically with Gallie wiring. Five human C1-C2 specimens were tested flexion/extension rotation intact, then after wiring fixation. Mean length was 39 mm, 25 mm the C2 lamina 14 lateral mass. Angular displacement screwed significantly less than control or wired groups. Stiffness at 0–0.5 Nm loads greater for controls (101 ± 49 Nm, 10.3 9.2...

We performed a study on twenty-one cadaveric fingers (seven non-paired forearms) to determine the pathomechanics of closed traumatic rupture flexor tendon pulleys in rock climbers. The ages individuals at time death ranged from sixty-one eighty-four years (mean, seventy-four years). forearm was placed custom-made loading apparatus, and individual were tested separately under simulated vivo conditions. digitorum superficialis profundus tendons each digit attached computer-controlled linear...

We measured the distribution of contact area and pressure between acetabulum femoral head cadaveric pelves in three different conditions: intact, with an operatively created fracture posterior wall, after anatomical reduction fixation a buttress plate interfragmentary screws. The study involved eight hip joints from five loaded to 2000 newtons simulated single-limb stance. Measurements were made pressure-sensitive film. was divided into areas--the anterior superior aspect, wall--for analysis...

Metatarsal stress fractures occur in military recruits after long marches and athletes episodes of overtraining involving running or jumping. It has been demonstrated that contraction the plantar flexors toes helps to counteract moments placed on metatarsals by body weight. is possible physiological fatigue due strenuous repetitive exercise reduces rate force flexors, thereby increasing metatarsal strain per cycle, this mechanism primary cause these bones. To test hypothesis causes increased...

Abstract The binding of metal ions from salts and corrosion products 316 LVM stainless steel MP‐35 to blood cells serum proteins was studied in vitro. In the first series experiments, were added whole then separated into red cells, white serum. Nickel nickel chloride or bound very small quantities cells. Cobalt cobalt both Chromium chromic (Cr 3+ ) whereas chromium potassium dichromate 6+ showed high some a second experiments its components pattern identical. third which had interacted with...

We investigated the existence of a midtarsal joint locking mechanism using cadaveric simulations normal gait. Previous descriptions this phenomenon led us to hypothesize that non-coupled rotations calcaneocuboid and talonavicular (i.e., midtarsal) joints cubonavicular talocalcaneal occur at heel strike during weight acceptance, after which cease with all bone-to-bone orientations remaining constant latter portions stance phase. Three-dimensional kinematics talus, calcaneus, cuboid, navicular...

This investigation studied the effects of simulated plantar flexor muscle activity on forefoot loading using a static cadaver model. Nine feet were mounted in an apparatus heel rise position. Using computer-controlled and pneumatic actuators, forces simultaneously applied to tendons triceps surae, hallucis longus, digitorum peroneus brevis tibialis posterior until 750 N ground reaction force was achieved, at which time pressure patterns captured immediately with pedobarograph. Second...

The indications for open reduction and internal fixation of posterior wall acetabular fractures associated with a clinically stable hip joint are unclear. In previous work large defect (27% articular surface area) resulted in significant alteration load transmission across the hip; specifically, there was transition from evenly distributed loading along to concentrated mainly superior portion during simulated single leg stance. However, majority involve smaller amount surface. Posterior not...