bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional evaluation of total knee replacement
Authors: Laughman R. Keith , Stauffer Richard N. , Ilstrup Duane M. , Chao Edmund Y. S. 
Published: February 2005

AbstractThe assessment of patients following prosthetic knee replacement suffers from a lack of objective criteria. An automated method of laboratory assessment that permits the objective evaluation of knee joint function is described. Nine biomechanical parameters were statistically selected, weighted, and combined to develop a Performance Index (Ip). One hundred ninety‐two patients (274 diseased knees) were studied prior to total knee replacement surgery, with 107 patients (138 knees) returning for a 1‐year postoperative study. Preoperative rheumatoid knees were found to have significantly poorer function than those involved with degenerative disease. Overall, the patients experienced a marked improvement 1 year post‐total knee replacement (TKR), with their functional scores approaching the lower limits of normal. Prostheses were assessed according to generic classes as well as specific design types. The newer generation devices were found to produce better functional results. In the patients receiving Anametric and Total Condylar total knee devices, a patellar resurfacing component was found to produce improved knee function in comparison with patients receiving the same prosthesis but without patellar resurfacing.
Bone density in osteopenic women: A modified distal radius density measurement procedure to develop an “at risk” value for use in screening women
Authors: Grubb S. A. , Jacobson P. C. , Awbrey B. J. , McCartney W. H. , Vincent L. M. , Talmage R. V. 
Published: February 2005

AbstractThis study measured radial and lumbar spine bone density in postmenopausal white female patients with nontraumatic fractures and their agematched controls. Bone density measurements were made with a single‐beam densitometer. Distal radial bone density measurements were made at the site at which the radius and ulna are separated by 5 mm, which is ∼5 mm from the distal radioulnar joint. Lumbar spine density was obtained using a dualbeam densitometer. Density at the commonly used “2/3” site near the midradius was also measured. Forty‐six crush fracture osteoporotic patients, 35 hip fracture patients, and 20 osteopenic patients referred to the clinic for back pain or excessive bone loss but with no history of nontraumatic fracture were studied. Bone density values at all sites in the patient populations were statistically reduced from control values (p < 0.01). At a mean age of 62 years, density of the midradius was 12% below the control value. However, both vertebral and distal radial densities (“5 mm” site) were 25% below control values. The spine/distal radius ratio remained constant. It was demonstrated that bone density at the modified distal radial site could be used to predict vertebral density in osteopenic patients. An “at risk” value useful in screening procedures was determined as that distal radius density value ⩾95% of all values from fracture patients—325 mg/cm2. It is concluded that distal radial density at the new “5 mm” site can be used in conjunction with midradius density as a preliminary test for both generalized and trabecular bone mass loss in women.
Cell culture of rabbit meniscal fibrochondrocytes: Proliferative and synthetic response to growth factors and ascorbate
Authors: Webber Richard J. , Harris Mary G. , Hough Aubrey J. 
Published: February 2005

AbstractThis study was undertaken to determine whether the cells of the fibrocartilaginous meniscal substance are capable of proliferation and matrix synthesis. Cells were isolated from the fibrocartilaginous menisci of young New Zealand white rabbits, and grown in two alternative culture regimens differing only in the basal nutrient medium used to initiate primary monolayer growth. Under each culture regimen, the cells attached and proliferated both initially and after passage into secondary (2°) culture. Differences were noted in cell morphology and time to reach confluence in primary (1°) culture. Upon passage into 2° culture, the fibrochondrocytes assumed two distinct morphological changes were accompanied by differences in the population doubling time and incorporation of 35SO4 into sulfated proteoglycans. The proliferation of both fibrochondrocyte subtypes was stimulated by the addition of either pituitary fibroblast growth factor (FGF) or human platelet lysate in a dosedependent manner. Both FGF (10 ng/ml) and ascorbate (40 μg/ml) decreased 35‐sulfate incorporation, whereas only ascorbate was found to alter the amount of sulfated glycosaminogly can in the pericellular coat. We conclude that the fibrochondrocytes of the meniscal substance are capable of replication and synthesis of matrix macromolecules if given the proper stimuli. Additionally, there may be two subpopulations of fibrochondrocytes that can be distinguished by their in vitro behavior.
Finger joint contact areas and pressures
Authors: Moran James M. , Hemann John H. , Greenwald A. Seth 
Published: February 2005

AbstractAlthough the joints of the index finger are similar geometrically and kinematically, the occurrence of degenerative joint disease is more frequent and severe in the distal interphalangeal joint. Much circumstantial evidence exists to suggest a mechanical cause for the observed differences in frequency. This article presents the results of in vitro experiments designed to determine contact areas and average pressures in the joints of the human index finger for positions simulating tip pinch and power grasp. The results show that the highest average contact pressures do, in fact, occur in the distal interphalangeal joint. Average joint contact pressure correlates well with clinically observed patterns of frequency of degeneration and degenerative joint disease score. This correlation between clinical experience and experimental results indicates that mechanical stress is among the factors responsible for the initiation and/or propagation of degenerative joint disease in the joints of the finger.
Kinematic behavior of the human wrist joint: A roentgen‐stereophotogrammetric analysis
Authors: de Lange A. , Kauer J. M. G. , Huiskes R. 
Published: February 2005

AbstractUsing a roentgen‐stereophotogrammetric measurement system, the three‐dimensional kinematic characteristics of each carpal bone in two human wrist joints were obtained as the hands were moved in vitro through dorsopalmar flexion and through radioulnar deviation, both in the supinated and pronated positions of the hand. The results were described in terms of Euler rotation angles and showed that in flexion, the distal carpal bones may be considered as one fixed group while the proximal carpals may not. For the deviation motion, quite different rotational excursions for the carpal bones were observed, therefore, none of the two rows may be assumed acting as rigid groups. In both of the hand motions performed, all carpal bones moved synchronously and uniformly. These results demonstrate that accurate measurements of three‐dimensional carpal‐bone motions are feasible by using an adequately refined roentgen‐stereophotogrammetric system. The detailed and precise kinematic information obtained can serve as a database for future developments of functional wrist‐joint models, and will provide more insight into carpal‐bone behavior, useful in clinical diagnosis and surgical reconstruction procedures.
Antibodies to synovial‐derived cells in patients undergoing artificial prosthesis implants
Authors: Ende Norman , Orsi Ernest V. , Buechel Frederic F. , Baturay Nesrine Z. , Zelikoff Judy T. 
Published: February 2005

AbstractIn this preliminary study, the authors have found cytotoxic complement‐dependent synovial antibodies in the serum of patients undergoing prosthesis implantation; these were particularly evident in those patients undergoing revision surgery. In order to demonstrate the synovial antibodies, it was necessary that the authors modify the method they had previously used in their studies of cytotoxic lung and kidney antibodies. While conventional trypsinization dispersion produced synovial target cells that would not react in the test system, mechanical dispersion successfully produced target cells sensitive to complement‐dependent cytotoxic antibodies. In this study, synovial antibodies reacted similarly to cells derived from the synovium of different individuals, but they did not react to cells derived from tissues other than synovium. This tissue specificity was confirmed by absorption studies that indicated the synovial antibodies to be organ specific. Whether these cytotoxic synovial antibodies can be predictive of the impending loss of an artificial prosthesis, or somehow be directly involved in the failure mechanism of that prosthesis, will require additional studies.
Chemotherapy‐induced alterations in the biomechanics of rat bone
Authors: Pelker Richard R. , Friedlaender Gary E. , Panjabi Manohar M. , Markham Thomas , Hausman Michael , Doganis Andrew C. , McKay Jim 
Published: February 2005

AbstractThe effects of methotrexate and doxorubicin (Adriamycin) on intact and fractured bone were studied in a rat model. Methotrexate, 0.1 mg/kg i.p., was administered five times a week, or doxorubicin, 1 mg/kg i.v., was given once a week. Animals were killed and evaluated at 4, 8, 12, and 16 weeks after surgical production of a unilateral femoral osteotomy and initiation of the chemotherapeuitic program. Both intact and fractured bones were tested to failure in rapid torsion, and the torque, angular deformation, stiffness, and energy were measured. There was a significant alteration in the strength of the healing osteotomies in doxorubicin‐ and methotrexate‐treated animals compared with the control group. The torsional strength of intact bone was not significantly altered by either drug protocol over the period of this observation.
Swing phase control with knee friction in juvenile amputees
Authors: Hicks R. , Tashman S. , Cary J. M. , Altman R. F. , Gage J. R. 
Published: February 2005

AbstractAbove‐knee amputees have a slower than normal walking velocity. In conventional prostheses the solution has been to apply knee friction to attempt to match the cadence of the prosthetic limb. Using kinematic data, we investigated the effect of variable knee friction on the swing phase of gait in juvenile amputees. The subjects were instructed to walk at a comfortable pace and were tested repeatedly with varying amounts of knee friction. We found that the excursion of the prosthetic shank as measured by knee range of motion was altered by changing the amount of knee friction. The period of the prosthetic shank remained constant when measured dynamically during gait. Therefore, knee friction is an effective means of providing the amputee with a more symmetrical appearing gait by matching the heel rise of the prosthetic limb to the sound limb. It is not an effective means, however, of matching the cadence of the prosthetic limb to the sound limb.
Forces in the normal and abnormal hand
Authors: An K. N. , Chao E. Y. , Cooney W. P. , Linscheid R. L. 
Published: February 2005

AbstractAn analytc model for human hand force analysis was developed through anatomical study and measurement of multiple cadaveric specimens. A method of solution was developed to determine muscle and joint force distributions under various isometric hand functions. Applications of this model to abnormal conditions include studying the effects of tendon laceration, neuromuscular weakness, and surgical restoration by tendon transfer. Limitations and further applications of the model are discussed in detail.
Morphological and biochemical effects of sodium morrhuate on tendons
Authors: Maynard J. A. , Pedrini V. A. , Pedrini‐Mille A. , Romanus B. , Ohlerking F. 
Published: February 2005

AbstractThe purpose of this study was to determine some of the morphological and biochemical effects of sodium morrhuate injections into intact rabbit patellar tendons and Achilles tendons. The effects of one, three, and five 100 μ1 injections of sodium morrhuate on tendon circumference, cell content, collagen fibril diameter, collagen‐proteoglycan relationships, water content, amino sugar content, and hydroxyproline content were investigated over periods of 1, 4, and 9 weeks. In general, sodium morrhuate injected tendons were larger in diameter and contained more cells, smaller collagen fibrils, increased water and amino sugar content, and reduced hydroxyproline content compared with their contralateral controls. As a sclerosing agent, sodium morrhuate appears to mimic the early stages of an injury‐repair sequence when injected directly into intact tendons. Whether sodium morrhuate may hasten repair responses or improve joint laxity remains to be determined.
Comparative study of neutral proteoglycanase activity by growth plate zone
Authors: Ehrlich Michael G. , Tebor Gary B. , Armstrong Ann L. , Mankin Henry J. 
Published: February 2005

AbstractThe degradation of proteoglycans has been considered an essential step in the process of endochondral ossification. Neutral proteases, described in the growth plate, have been implicated in this process. If these neutral proteases are important in the endochondral process, their level of activity should be highest at the point where calcification is occurring. This study measures neutral protease activity with a quantitative viscometric assay throughout all zones of the bovine growth plate. The results demonstrate that the enzyme is present throughout all zones of the growth plate. However, enzyme levels in the lower hypertrophic and calcifving zones are significantly higher than anywhere else. The enzymes came from the cartilage cells and not from the invading vasculature. This implied proof of the role of neutral proteases in the endochondral process implies that by inhibiting this class of enzymes, one should be able to block endochondral ossification.
Amelioration of oxygen‐induced osteoporosis in the in vitro fetal rat tibia with a capacitively coupled electrical field
Authors: Brighton Carl T. , Nichols Claude E. , Arangio George A. 
Published: February 2005

AbstractNear‐term fetal rat tibiae were grown in M.E.M. Eagle/NCTC 135/15% newborn calf serum in 5% carbon dioxide and 5, 10, 21, 35, 60, and 90% oxygen for 3, 7, 10, and 14 days. Linear growth of the explants, as measured from macrophotographs of the explants at day zero and each of the days above, was greastest in the lower oxygen concentrations and least in the days above, was greastest in the lower oxygen concentration and least in the higher oxygen concentrations. Breaking strengths of the tibial diaphyses were signigicantly reduced in those explants grown in 60 and 90% oxygen. When the fetal rat tibiae were grown in 60% oxygen for 7 days and were subjected to a capacitively coupled electrical signal (sine wave, 60 kHz, 10 V peak‐to‐peak output signal; current density and field in the culture dish calculated to be 5.2 μA/ cm2 and 0.32 mV/cm, respectively), the breaking strengths and middiaphyseal widths were statistically significantly greater than control tibiae grown in 60% oxygen alone. It is concluded that an appropriate capacitively coupled elecmalian long bone model.
Monitoring the healing of a tibial osteotomy in the rabbit treated with external fixation
Authors: Kaplan S. J. , Hayes W. C. , Mudan P. , Lelli J. L. , White A. A. 
Published: February 2005

AbstractFercture site axial rigidity was monitored nonestructively at weekly intervals during healing of tibial osteotomies in adult rabbits. Two groups of 20 rabbits each were treated with external fixators of two different rigidities. Four animals from each group were killed at 3,5,6,7, and 8 weeks to determine the bending moments at failure of the healing fractures. Normal fracture healing was accompanied by characteristic phases in the development of fracture site axial rigidity. From 0 to 3 weeks there was a period of low and approximately constant rigidity, followed by a linear increase during 3 to 5 weeks to an approximately three to four times greater rigidity. The maximum average normalized axial rigidities were reached at 6 weeks and were 57% (high rigidity group) and 77% (low rigidity group) of the untreated contralatreal controls. The Maximum average normalized failure moments occurred at 8 weeks and were 48% (high rigidity) and 44% (low rigidity) of controls. The differences due to fixator rigidity were not statistically significant except for a large increse in failure moments at 3 weeks for the low rigidity group. Axial rigidities were correlated (r2 = 0.74 and 0.53, respectively) with failure moments, but only during the first 6 weeks. The monitoring technique provides a nondestructive means for following the biomechanical progress of fracture healing in in an animal model. The occurrence of the characteristic increase in fracture site axial rigidity at 3 to 5 weeks can also be used to distinguish between normal and abnormal healing.
Parametric analyses of pin‐bone stresses in external fracture fixation devices
Authors: Huiskes R. , Chao E. Y. S. , Crippen T. E. 
Published: February 2005

AbstractProblems occuring in the use of external fixators for bone fractures include pin‐bone interface necrosis, infection, and loosening. These may be initiated and enhanced by Pin‐bone interface stress levels. Based on stress data from finite element method (FEM) models, an analytical “closed‐form” model of the local pin‐bone configuration in long‐bone fracture fixation is developed. This model is relatively simple and useful for routine applications in combination with clinical studies and animal experiments. Although approximate well with more sophisticated FEM analysis results.The analytical model is used for extensive parametric analyses, investigating the effects on the pin‐bone interface stress distribution of frame configuration parameters, pin diameter and modulus, bone dimensions, and elastic characteristics. The results indicate that these stresses may reach very high levels under unfavorable circumstances but can be drastically reduced by increasing the bending rigidity of the pin, reducing the side‐bar separation and applying full‐pin configuration in favor of half‐pins.
Microvascular and histologic effect of circumferential wire on appositional bone growth in immature dogs
Authors: Wilson James W. , Rhinelander Frederic W. , Stewart Charles L. 
Published: February 2005

AbstractCircumferential wires were placed around both midshaft femora of six immature dogs. On one side the wires were placed under the periosteum and on the other side the wires were placed over the periosteum. All wires were tightened to an equivalent tension. A diffuse growth of periosteal new bone occurred in those femora in which wires were placed under the periosteum but not in those over the periosteum. Corresponding microangiographs at 3 weeks in those femora in which wires were placed under the periosteum revealed dramatically increased medullary and periosteal vascularity coupled with histologic active trabecular bone formation. In those femora in which the wires were placed over the periosteum, even though the placement of the wires should supposedly have been the most detrimental, vascularity was not restricted. There were perfused vessels within the cortex directly under the wires. At 8 weeks the wires in both preparations were becoming encased in the growing cortical bone. Cerclage did not devitalize immature bone nor did it restrict adjacent appositional bone growth.
In vivo bone mineral analysis throughout skeletal growth in rats: Differences due to sex or vitamin D deficiency
Authors: Awbrey Brain J. , Hagaman John R. , Lester Gayle E. , Talmage Roy V. 
Published: February 2005

AbstractThis study reports a new technique for the measurements of bone mineral content (BMC) in live rats. A single photon absorptiometric instrument has been adapted for rapid, reproducible measurement of BMC. Four bone sites were selected for use, based on ease of positioning and reproducibility of measurement; these were as follows: proximal femur, midfemur, proximal seventh caudal vertebra, and midseventh caudal vertebra. Significant increases were detected when BMC was measured at biweekly intervals from weaning to 18 weeks of age in normal male rats. Comparison of body growth and changes in BMC of male and female rats with age showed that body weight gain of female rats slowed earlier than that of male rats whereas BMC increased at similar rates in both sexes. Vitamin D deprivation from day 24 of life resulted in decreased BMC at all four measurement sites compared with such measurements in normal control rats. Differences were detectable after 8 weeks of age and occurred despite the maintenance of serum calcium levels within normal range and only slight reduction in body weights of vitamin D deprived rats. These studies demonstrate that single photon absorptiometry can be used to mointor changes in BMC in live rats on a routine basis without harm to the animals. Changes in BMC such as those due to growth or vitamin D deprivation can easily be quantitated using this technique.
Descriptive anatomy of fibrocartilaginous menisci in the finger joints of the hand
Authors: Fisher D. M. , Elliott S. , Cooke T. D. V. , Forrest W. J. 
Published: February 2005

AbstractObservations were made from the dissection of 156 digital joints (thumbs excluded). In all joints fibrocollagenous menisci projected into the articular cavity from a ring‐like structure based on the joint capsule. These meniscal structures separated the articulating cartilage surfaces at the margins of the joint. Histological examination confirmed a fibrocartilaginous nature of the tissue which demonstrated positive staining for proteoglycans and collagen fibers. Although generally similar in form, these meniscal structures varied in extent when compared between joint groups. The greatest amount and articular contribution was noted in metacarpophalangeal joints with least being found distally.
Bovine xenograft collateral ligament replacement in the dog
Authors: McMaster William C. 
Published: February 2005

AbstractA Study of the use of glutaraldehyde‐stabilized bovine xenograft material as a collateral ligament replacement in 16 dogs has been done. Six xenograft implant complexes harvested 4 months postoperatively failed in tension at 772.2 ± 463.5 versus 799.7 ± 162.7 N ( ± 1 SD) for controls (p > 0.05, paired t test). Histologic evaluation in 10 dogs after implants of up to 1 year duration demonstrated a progressive invasion of the xenograft by host tissues. Xenograft remnants were easily identifiable at 1 year. The host tissues invaded in parallel to the passive collagen scaffolding of the xenograft and consisted of vessels and fibroblastic elements that produced collagen of host origin.
Piezoelectric internal fixation devices: A new approach to electrical augmentation of osteogenesis
Authors: Cochran G. V. B. , Johnson M. W. , Kadaba M. P. , Vosburgh F. , Ferguson‐Pell M. W. , Palmeiri V. R. 
Published: February 2005

AbstractPrototype testing has been accomplished on a piezoelectric, internal fixation plate. This device combines a piezoelectric material with an internal fixation device as an integrated structure that provides mechanical stability, together with self‐generated electrical stimulation, for treating fractures and nonunion. In bench and animal tests we have demonstrated that cyclical loading can cause a device of this type to generate electrical charge while attached to bone. After rectification, direct currents within the range known to stimulate osteogenesis can be produced by weighed‐bearing loads. Furthermore, electrical output of the implants can be increased by externally applied ultrasonic energy. These twin developments and significantly to the potential armamentarium of devices to enhance bone healing.