The restoration of articular surfaces overlying replamineform porous biomaterials

Although joints with synovial cavities and articular surfaces are very variable, they all have one common peculiarity. In most cases, one of the articular surfaces is concave, whereas the other one is convex. During the formation of a joint, the epiphysis, which has less kinetic energy during the movements in the joint, forms a convex surface, whereas large kinetic energy forms the epiphysis with a concave surface. Basing on this concept, the analysis of the structure of the joints, allows to determine forces involved into their formation, and to identify the general patterns of the formation of the skeleton.

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1. On the Mechanism of the Knee Joint

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600033654 ◽

1862 ◽

Vol 4 ◽

pp. 67-73 ◽

Cited By ~ 1

Author(s):

Goodsir

Keyword(s):

Knee Joint ◽

Articular Surfaces

After alluding to the comparatively superficial manner in which physiologists, with the exception of the brothers Weber, have hither-to investigated the structure and movements of the joints, the author gave an abstract of the general results which he had formerly obtained in an examination of the knee-joint, made with reference to Meyer's valuable observations. He had found that, as stated by Meyer, the thigh and leg rotate on one another in opposite directions,—at the close of extension, and at the commencement of flexion; and that the co-ordinated movements in the patella, the ligaments, and muscles correspond generally with the account given by that observer; but in addition he had ascertained what had previously escaped notice,1. That the articular surfaces of the femur, tibia, and patella are not continuous but faceted surfaces.

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Using in-situ process monitoring data to identify defective layers in Ti-6Al-4V additively manufactured porous biomaterials

Journal of Manufacturing Processes ◽

10.1016/j.jmapro.2021.03.002 ◽

2021 ◽

Vol 64 ◽

pp. 1248-1254

Author(s):

Darragh S. Egan ◽

Caitríona M. Ryan ◽

Andrew C. Parnell ◽

Denis P. Dowling

Keyword(s):

Process Monitoring ◽

Monitoring Data ◽

Porous Biomaterials

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Ordosemys leios, n.gen., n.sp., a new turtle from the Early Cretaceous of the Ordos Basin, Inner Mongolia

Canadian Journal of Earth Sciences ◽

10.1139/e93-184 ◽

1993 ◽

Vol 30 (10) ◽

pp. 2128-2138 ◽

Cited By ~ 50

Author(s):

Donald B. Brinkman ◽

Jiang-Hua Peng

Keyword(s):

Early Cretaceous ◽

Inner Mongolia ◽

Cervical Vertebrae ◽

Ordos Basin ◽

Sister Group ◽

Sister Group Relationship ◽

Articular Surfaces ◽

Caudal Vertebrae ◽

The Ordos Basin

Ordosemys leios, n.gen., n.sp., from the Early Cretaceous Luohandong Formation, Zhidan Group, Ordos Basin, Inner Mongolia, is a primitive aquatic turtle with a reduced, fenestrated plastron. It shares with the members of the Centrocryptodira the presence of well-formed articular surfaces on the cervical and caudal vertebrae. Within the Centrocryptodira, characters of the cervical vertebrae suggest it is more closely related to the Polycryptodira than is the Meiolaniidae. Ordosemys shares with the Chelydridae the presence of two procoelous anterior caudals, but this character may be primitive for the Polycryptodira. Characters of the basicranial region of the braincase shared by Ordosemys and the Chelonioidea support a sister-group relationship between these two taxa, but a sister-group relationship between Ordosemys and the Polycryptodira is more strongly supported by characters shared by the Chelonioidea and other members of the Polycryptodira.

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Stress-Distribution Pattern Across the Glenohumeral Joint in Collegiate and Professional Baseball Players: A Computed Tomography Osteoabsorptiometry Study

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211009185 ◽

2021 ◽

Vol 9 (6) ◽

pp. 232596712110091

Author(s):

Kyosuke Numaguchi ◽

Daisuke Momma ◽

Yuki Matsui ◽

Masashi Yokota ◽

Jun Oohinata ◽

...

Keyword(s):

Bone Density ◽

Stress Distribution ◽

Glenohumeral Joint ◽

Distribution Patterns ◽

Joint Surface ◽

Baseball Players ◽

Articular Surfaces ◽

Head Surface ◽

The Mean ◽

Dominant Side

Background: The influence of long-term loading conditions on the articular surfaces of the glenohumeral joint can be determined by measuring stress-distribution patterns. Long-term pitching activity changes the stress distribution across the glenohumeral joint surface; however, the influence of competitive level on stress-distribution patterns remains unclear. Purpose: To use computed tomography (CT) osteoabsorptiometry (CTOAM) to evaluate the distribution of subchondral bone density across the glenohumeral joint in collegiate and professional baseball players as well as to determine the effects of pitching activity on the articular surfaces. Study Design: Descriptive laboratory study. Methods: We evaluated 73 shoulders in 50 baseball players. CT imaging data were obtained from the dominant-side shoulder of 12 professional pitchers (PP group) and 15 professional fielders (PF group). CT imaging data were also obtained from both shoulders of 12 asymptomatic collegiate pitchers (CP group) and 11 collegiate fielders (CF group). The pattern of distribution of subchondral bone density across the articular surfaces of each glenohumeral joint was assessed by CTOAM. As a measure of bone density, the mean Hounsfield units (HU) were obtained for each joint surface, and the absolute values of the dominant shoulder were compared for each group. Results: Stress-distribution patterns over the articular surfaces differed between the dominant and nondominant sides in the CP group as well as between both collegiate groups versus the PP group. In the CP group, the mean HU of the humeral head surface were greater on the nondominant versus dominant side ( P = .035). On the dominant side, the mean HU of the humeral head surface and glenoid were greater in the CP versus the PP group ( P = .001 and .027, respectively). Conclusion: Stress distribution on the articular surface of the glenohumeral joint was affected by pitching ability and competitive level. Our analysis indicates that the traction force on the glenohumeral joint surface might be greater than compression force during pitching. Clinical Relevance: The present findings suggest that pitching activity results in low stress to the articular surfaces of the glenohumeral joint. This supports the notion that mechanical conditions play a crucial role in the etiology of disorders specific to pitching activity.

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Development of a Tibial Slider to Evaluate and Validate a Finite Element Model for Friction in Total Knee Implants

10.1115/imece2000-2550 ◽

2000 ◽

Author(s):

Michael D. Nowak ◽

Kenneth Shaw ◽

Courtland Lewis

Keyword(s):

United States ◽

Finite Element ◽

Knee Replacement ◽

Severe Pain ◽

Element Model ◽

The United States ◽

Loss Of Function ◽

Articular Surfaces ◽

Joint Disorder ◽

Total Knee

Abstract More than 200,000 people in the United States annually undergo knee replacement as a means of diminishing pain and stiffness and restoring mobility, and the number is expected to increase with further advancements in joint replacement procedures [Duke, 1999]. Total knee replacement is performed on people with severe degenerative joint disorder such as osteoarthritis in which the articular surfaces of the knee deteriorate, leading to severe pain, limitation or loss of function and/or deformity of the joint.

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India Ink Pinprick Experiments on Surface Organization of Cricoarytenoid Joints

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.2904.544 ◽

1986 ◽

Vol 29 (4) ◽

pp. 544-548 ◽

Cited By ~ 4

Author(s):

Joel C. Kahane ◽

Alice R. Kahn

Keyword(s):

Articular Cartilage ◽

Collagen Fiber ◽

Collagen Fibers ◽

Articular Surfaces ◽

India Ink ◽

Age Related ◽

Cricoarytenoid Joint ◽

Mechanical Factors ◽

Fiber Organization

Collagen fiber organization in the articular surfaces of the cricoarytenoid joint (CAJ) was studied using a pinpricking technique used in biomechanical research in orthopedics. Four male human formalin preserved specimens (3 months to 20 years) and 6 male freshly autopsied specimens (19 to 30 yrs) were studied. Specimens were dissected using the stereomicroscope. Distinctive patterns of articular cartilage slits reflect the orientation of collagen fibers in the cricoid and arytenoid articular surfaces. The orientation of the collagen fibers reinforces the articular surfaces along the principle path of CAJ motion. No age related differences were found. This suggests that the orientation of collagen fibers in the CAJ articular surfaces is prenatally determined rather than significantly influenced by postnatal mechanical factors.

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