Nine fresh-frozen cadaveric specimens were disarticulated through the knee, and soft tissues, except for interosseous ligaments membrane, removed to level of ankle. The subtalar joint was secured with screws in neutral position (approximately 5 degrees valgus). Contact pressures tibiotalar measured use low-grade pressure-sensitive film, which placed an anterior capsulotomy. For each measurement, 700 newtons load applied specimen one minute. film imprints scanned, contact quantitated nine...

In Brief Study Design. Multidirectional flexibility tests were conducted on 10 human thoracic spines with intact rib cage. Objectives. To determine the amount of stability cage imparts to spine and show lost by a sternal fracture. Summary Background Data. There is no published study biomechanical testing cadaveric specimens intact. Methods. this study, tested using biaxial material machine an opto-electronic three-dimensional motion measuring device (Opto-trak 3020). The in axial...

This article presents criteria for the design of a lumbar intervertebral disc prosthesis that take into consideration issues endurance, materials behavior, geometry, kinetics, motion constraints, fixation to bone, and safety. The philosophies discussed are generally applicable in synthesis any new implant system. Specifications presented along with an evaluation based on some preliminary test data.

In vitro force and deformation measurements formed the basis for determinate, quasistatic analysis of principal forces in seated lumbar spine.To explore relationship between postures mechanical response component tissues intervertebral joints.Despite high prevalence low back pain syndrome, precise mechanisms relating specific loads to spinal degeneration are not well understood. Simultaneous, time-dependent measurement anterior column articular facet has been presented previously....

Twenty-six paired, fresh-frozen cadaveric feet were disarticulated at the ankle joint, and dome of talus was potted. Stress-risers placed along medial, lateral, posterior aspects calcaneus, specimen loaded rapidly to failure in a testing machine produce type-IIB displaced intra-articular fracture according classification system Sanders et al. One each pair treated with standard internal fixation bone-grafting (the control group), other similar but SRS (Skeletal Repair System) calcium...

Eight adult below-knee cadaver specimens were placed in a testing machine and loaded to 350 newtons according strict protocol. Arch height length measurements obtained each specimen with the toes resting on foot plate, dorsiflexed 30°, maximally manually. The plantar fascia was then divided from medial lateral one-quarter increments, effect arch assessed using same loading A consistent decrease arch-supporting function sequential sectioning of encountered. less reflected by increase fascia....

Background Previous radiofrequency work has not rigidly controlled energy application to the articular cartilage, giving uncertain results published date. Hypothesis At minimal settings, probes cause cell death in measurable areas when applied human cartilage. Study Design Controlled laboratory study. Methods Simulating operating room conditions, 5 commercially available were attached a customized jig standardize contact pressure of each probe tip 2.0 g. Keeping all variables same, placed on...

The purpose of this study was to determine the effects laser-induced collagen shortening on biomechanical properties inferior glenohumeral ligament complex. Fifty-seven bone-ligament-bone specimens underwent uniaxial tensioning 10% strain. Approximately half then by lasing using a holmium:yttrium-aluminum-garnet laser. Both groups were again tensioned strain, and loaded failure. Ultimate strain yield significantly higher in lased than nonlased specimens. No significant difference found for...

Two long-term wear behavior studies used in part of the process selecting best materials for a new all-metal orthopaedic spinal implant are presented. The relative and absolute volume rates candidate metals were investigated through simulation two bearing regions an intervertebral disc prosthesis. It was determined gravimetrically that hot isostatically pressed Co-Cr-Mo alloy provided lowest debris generation. had average rate 0.093 mm3/million cycles from spring-in-pocket 0.126 hinge...

Simulated syndesmosis injuries were created in 12 fresh-frozen, below-knee cadaver specimens. Six specimens repaired with a 4.5 mm stainless steel screw, and six polylactide screw. Three of each group tested load to failure by axially loading 1400 N externally rotating 90°. underwent fatigue testing 700 applying 2.5 N-m torque for 57,700 cycles. Radiographs computed tomography scans evaluated. None the screws broke or failed. Similar was noted control groups. Fatigue revealed no significant...

Seven fresh-frozen cadaver specimens had a calcaneal osteotomy performed obliquely through the posterior portion of calcaneus. Angular relationships between first metatarsal and talus were recorded with use motion-analysis system in transverse, sagittal, coronal planes. The specimen was mounted testing machine loaded via an intramedullary rod to 150, 350, 550 N. A flatfoot model created, repeat measurements obtained. then displaced 1 cm medially, made at each three load levels. returned its...

In Brief Study Design. The mechanical stability of cross-linked and control spinal motion segments was evaluated using neutral zone, range (ROM), instability score metrics. Objective. To determine if exogenous cross-linking could increase the segments. Summary Background Data. microstructure anulus fibrosus extracellular matrix can affect intervertebral joint. Parallel testing in our laboratory has shown that improve fatigue resistance fibrosus. Methods. There were 3 separate experimental...

Study Design. A magnetic resonance imaging technique was developed to measure creep in the lumbar spine different seated postures. Owing fixed size and horizontal orientation constraints of system bore, gravitational force simulated plane while subject assumed each two near-seated postures: 1) flexed lumbar, 2) extended lumbar. Objectives. One experiemental used determine feasbility this designed correlate spinal with Summary Background Data. Although epidemiologic pathologic studies have...

Translational mobilization techniques are frequently used by physical therapists as an intervention for patients with limited ranges of motion (ROMs). However, concrete experimental support such practice is lacking. The purpose the study was to evaluate effect simulated dorsal and ventral translational (DTM VTM) glenohumeral joint on abduction rotational ROMs.Fourteen fresh frozen shoulder specimens from 5 men 3 women (mean age=77.3 years, SD=10.1, range=62-91) were this study. Each specimen...