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Sesamoid Bones (sesamoid + bone)
Selected AbstractsRupture of the distal sesamoidean impar ligament with proximal displacement of the distal sesamoid bone in a steeplechaserEQUINE VETERINARY EDUCATION, Issue 3 2007A. G. Heitzmann First page of article [source] Morphologic changes associated with functional adaptation of the navicular bone of horsesJOURNAL OF ANATOMY, Issue 5 2007V. A. Bentley Abstract Failure of functional adaptation to protect the skeleton from damage is common and is often associated with targeted remodeling of bone microdamage. Horses provide a suitable model for studying loading-related skeletal disease because horses are physically active, their exercise is usually regulated, and adaptive failure of various skeletal sites is common. We performed a histologic study of the navicular bone of three groups of horses: (1) young racing Thoroughbreds (n = 10); (2) young unshod ponies (n = 10); and (3) older horses with navicular syndrome (n = 6). Navicular syndrome is a painful condition that is a common cause of lameness and is associated with extensive remodeling of the navicular bone; a sesamoid bone located within the hoof which articulates with the second and third phalanges dorsally. The following variables were quantified: volumetric bone mineral density; cortical thickness (Ct.Th); bone volume fraction, microcrack surface density; density of osteocytes and empty lacunae; and resorption space density. Birefringence of bone collagen was also determined using circularly polarized light microscopy and disruption of the lacunocanalicular network was examined using confocal microscopy. Remodeling of the navicular bone resulted in formation of transverse secondary osteons orientated in a lateral to medial direction; bone collagen was similarly orientated. In horses with navicular syndrome, remodeling often led to the formation of intracortical cysts and development of multiple tidemarks at the articular surface. These changes were associated with high microcrack surface density, low bone volume fraction, low density of osteocytes, and poor osteocyte connectivity. Empty lacunae were increased in Thoroughbreds. Resorption space density was not increased in horses with navicular syndrome. Taken together, these data suggest that the navicular bone may experience habitual bending across the sagittal plane. Consequences of cumulative cyclic loading in horses with navicular syndrome include arthritic degeneration of adjacent joints and adaptive failure of the navicular bone, with accumulation of microdamage and associated low bone mass, poor osteocyte connectivity, and low osteocyte density, but not formation of greater numbers of resorption spaces. [source] Influence of interleukin-1, and hyaluronan on proteoglycan release from equine navicular hyaline cartilage and fibrocartilageJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2000Frean Proteoglycan (PG) release, in response to recombinant human interleukin-1, (rh-IL-1,), was measured in cartilage explants obtained from the equine distal sesamoid bone (navicular bone). Fibrocartilage from the surface of the navicular bone apposing the deep digital flexor tendon and hyaline cartilage from the surface of the navicular bone articulating with the middle phalanx were labelled with 35SO4. Hyaline cartilage from the distal metacarpus was used as a control tissue. Following radiolabel incorporation, the three cartilage types were treated with rh-IL-1, (100 U/mL) in the presence of hyaluronan (0.2, 2, 20, 200 and 2000 ,g/mL). rh-IL-1,-Induced PG release was measured by scintillation assay of PG-bound radiolabel. Increases in PG release of 94% (P < 0.01), 101% (P < 0.05) and 122% (P < 0.05), in response to rh-IL-1,, were noted in fibrocartilage, navicular hyaline cartilage and metacarpal hyaline cartilage, respectively. Hyaluronan (0.2 ,g/mL) significantly reduced rh-IL-1,-induced PG release in metacarpal hyaline cartilage (P < 0.01). In fibrocartilage and navicular hyaline cartilage, hyaluronan did not reduce PG release and at some concentrations appeared to increase PG release, although this was not statistically significant. These experiments show that (i) fibrocartilage and hyaline cartilage of the navicular bone release PGs in response to rh-IL-1,, and (ii) hyaluronan does not prevent rh-IL-1,-induced breakdown of navicular bone cartilage. [source] A radiologic and histologic study of the os peroneum: Prevalence, morphology, and relationship to degenerative joint disease of the foot and ankle in a cadaveric sampleCLINICAL ANATOMY, Issue 6 2009C. Muehleman Abstract The present study investigated the prevalence of an os peroneum (OP, a sesamoid bone) in a cadaveric sample and its relationship to the shape of the cuboid tuberosity, and cartilage degeneration at the cuboid tuberosity and in regional joints within the foot (first metatarsophalangeal and calcaneocuboid) and ankle. The fibularis longus tendon of 33 embalmed human cadavers (mean age 81 years) were obtained from the anatomy laboratory. Nineteen of 64 tendons (30%) displayed an OP both radiographically and histologically. The os peronei ranged in size from small spicules to prominent masses: mean area 2.48 mm2 (left) and 2.70 mm2 (right). Histologically, the os peronei were cancellous bone, the largest occupying most of the tendon at the point of contact with the cuboid tuberosity. Fibrocartilage was present at their borders, merging with dense regular fibrous tissue and peritenon. The talocrural, calcaneocuboid, and first metatarsophalangeal joints were examined for cartilage integrity and osteophytes based on an earlier suggestion that there may be an association between degenerative joint disease and endochondral bone formation. There was no statistical correlation between presence of an OP with any of the following parameters: age, gender, body size, cartilage degeneration, or osteophytes within any of the joints examined. Therefore, the presence of an OP does not appear to be associated with increased endochondral ossification or degenerative joint disease. This study does not preclude the possibility that sesamoid bone formation may be associated with biomechanical functions within the foot; thus, future studies may be warranted. Clin. Anat. 22:747,754, 2009. © 2009 Wiley-Liss, Inc. [source] Arterial anatomy of the hallucal sesamoidsCLINICAL ANATOMY, Issue 6 2009Bjoern Rath Abstract The aim of this study was to analyze the arterial supply of the sesamoid bones of the hallux. Twenty-two feet from adult cadavers were injected with epoxide resin or an acrylic polymer in methyl methacrylate (Acrifix®) and subsequently processed by two slice plastination methods and the enzyme maceration technique. Afterwards, the arterial supply of the sesamoid bones was studied. The first plantar metatarsal artery provided a medial branch to the medial sesamoid bone. The main branch of the first plantar metatarsal artery continued its course distally along the lateral side of the lateral sesamoid and supplied it. The supplying arteries penetrated the sesamoid bones on the proximal, plantar, and distal sides. The analysis and cataloging of the microvascular anatomy of the sesamoids revealed the first plantar metatarsal artery as the main arterial source to the medial and lateral sesamoid bones. In addition, the first plantar metatarsal artery ran along the lateral plantar side of the lateral sesamoid bone, suggesting that this artery is at increased risk during soft-tissue procedures such as hallux valgus surgery. Clin. Anat. 22:755,760, 2009. © 2009 Wiley-Liss, Inc. [source] Absence of the medial sesamoid bone associated with metatarsophalangeal painCLINICAL ANATOMY, Issue 7 2006Ulunay Kanatli Abstract Pain at the first metatarsophalangeal (MTP) joint can result from inflammation, chondromalacia, flexor hallucis brevis tendinitis, osteochondritis dessecans, fracture of a sesamoid bone, avascular necrosis of sesamoids, inflamed bursae, intractable keratoses, infection, sesamoiditis, gout arthropathy, and rheumatoid arthritis. Congenital absence of a sesamoid bone is extremely rare. We present a 17-year-old male patient with pain at the plantar aspect of the right MTP joint associated with congenital absence of the medial sesamoid. There was tenderness and the range of motion was minimally restricted. He described the pain as necessitating changes in his social life. On radiographs, the medial hallucial sesamoid was absent on the right side. The MTP joint was also evaluated using magnetic resonance imaging (MRI). A metatarsal pad was prescribed and the patient was satisfied with the treatment at the 2 months follow-up period. MRI revealed no pathological tissue at the medial sesamoid site. Hallucial sesamoids absorb pressure, reduce friction, protect the tendons, act like a fulcrum to increase the mechanical force of the tendons, and provide a dynamic function to the great toe by elevating first metatarsal head. Congenital absence of these bones is very rare but we must consider it in a patient with MTP joint pain. Clin. Anat. 19:634,639, 2006. © 2006 Wiley-Liss, Inc. [source] Occurrence and distribution of sesamoid bones in squamates: a comparative approachACTA ZOOLOGICA, Issue 3 2010Adriana Jerez Abstract Jerez, A., Mangione, S. and Abdala, V. 2010. Occurrence and distribution of sesamoid bones in squamates: a comparative approach.,Acta Zoologica (Stockholm) 91: 295,305 Sesamoids are defined as skeletal elements that develop within a continuous band of regular dense connective tissue (tendon or ligament) adjacent to an articulation or joint. In this work, we discuss developmental data on two squamate species, provide data on the onset of the squamate sesamoids and the muscles they are associated to. Our results show that Mabuya mabouya and Liolaemus albiceps exhibited rather similar ontogenetic patterns and that the first sesamoids appear in embryos. The ossifying sesamoid timing is different between M. mabouya and L. albiceps, being faster in the former. In adults, we found 41 sesamoids, considering both fore and hindlimbs. We did not find any intrataxonomic differences, or any differences between the right and left side of the specimens in relation to the sesamoid presence. We recognize four types of sesamoids: (1) embedded sesamoids; (2) interosseus sesamoids; (3) glide sesamoids; and (4) supporting sesamoids. A table is included with a preliminary survey of the sesamoid distribution pattern in 10 Squamate clades. [source] Effects of hind limb denervation on the development of appendicular ossicles in the Dwarf African Clawed Frog, Hymenochirus boettgeri (Anura: Pipidae)ACTA ZOOLOGICA, Issue 4 2009Hyoung Tae Kim Abstract Sesamoids and other appendicular ossicles are common in other classes of vertebrates but comparatively rare in amphibians. The pipid frog Hymenochirus boettgeri (Boulenger, G. A. 1899. On Hymenochirus, a new type of aglossal batrachians. , Annals of the Magazine of Natural History Series 7: 122,125) is unusual among anurans in having seven (or more) appendicular ossicles in each hind limb. Sesamoids are often associated with muscles and tendons, and their development is usually regarded as mediated by or correlated with function. This study investigated the effects of paralysis (loss of function) on development of ossicles in the hind limb of Hymenochirus. Complete denervation of the right sciatic nerve was performed at developmental stages 63 and 66, and the animals maintained for a further 6,7 or 12,13 weeks. Specimens were cleared and double stained for cartilage and bone. There were no gross morphological differences between control and sham operated groups. The lunulae were not affected by paralysis, whereas the fabella arose later and/or regressed in some specimens. The distal os sesamoides tarsalia (OST) was shorter in paralysed individuals, and both the distal OST and cartilagines plantares showed delayed maturation. Denervation of the hind limb thus affected the timing of appearance, maintenance and rate of maturation of some sesamoid bones in Hymenochirus, but had no effect on others. [source] Bilateral degenerative suspensory desmitis with acute rupture in a Standardbred coltEQUINE VETERINARY EDUCATION, Issue 6 2010K. D. Miller Summary A 3-month-old Standardbred colt was examined for acute, bilateral hindlimb swelling and lameness. Serum chemistry demonstrated elevated muscle enzymes (AST, ALT, LDH and CK). Radiographs of the hindlimbs demonstrated intact proximal sesamoid bones that were displaced distally and subluxation of the pastern joints. Ultrasonography of the affected areas revealed large, diffuse hypoechoic areas in the bodies of both hind suspensory ligaments consistent with bilateral rupture. Histology of the lesions was consistent with degenerative suspensory desmitis with acute rupture. [source] Arterial anatomy of the hallucal sesamoidsCLINICAL ANATOMY, Issue 6 2009Bjoern Rath Abstract The aim of this study was to analyze the arterial supply of the sesamoid bones of the hallux. Twenty-two feet from adult cadavers were injected with epoxide resin or an acrylic polymer in methyl methacrylate (Acrifix®) and subsequently processed by two slice plastination methods and the enzyme maceration technique. Afterwards, the arterial supply of the sesamoid bones was studied. The first plantar metatarsal artery provided a medial branch to the medial sesamoid bone. The main branch of the first plantar metatarsal artery continued its course distally along the lateral side of the lateral sesamoid and supplied it. The supplying arteries penetrated the sesamoid bones on the proximal, plantar, and distal sides. The analysis and cataloging of the microvascular anatomy of the sesamoids revealed the first plantar metatarsal artery as the main arterial source to the medial and lateral sesamoid bones. In addition, the first plantar metatarsal artery ran along the lateral plantar side of the lateral sesamoid bone, suggesting that this artery is at increased risk during soft-tissue procedures such as hallux valgus surgery. Clin. Anat. 22:755,760, 2009. © 2009 Wiley-Liss, Inc. [source] Incidence and ossification of sesamoid bones in the hands and feet: A radiographic study in an Arab populationCLINICAL ANATOMY, Issue 4 2007A.S. Dharap Abstract The incidence and ossification of sesamoid bones in the hands and feet were studied in 922 radiographs (400 hands and 522 feet) in an Arab population from Bahrain, 5,83 years of age and consisting of 549 adults (393 men and 156 women) and 373 children (286 boys and 97 girls). All radiographs of the hand and foot in the adult population showed two sesamoid bones in the thumb metacarpophalangeal (MCP) joint and in the hallucal metatarsophalangeal (MTP) joint, respectively. Only 2.3% and 1.5% of hands showed sesamoids at the MCP joints of the middle and ring fingers respectively compared to a reported incidence of 7.1% for each digit in Caucasians. The incidence of sesamoids in the MTP joints of third and fourth toes (0.6% each) and inferior to the hallucal interphalangeal joint (3.1%) is probably the lowest reported so far in the literature. In the hands, ossification commenced first in the thumb sesamoids, at the age of 10 years in females and 11 years in males and was completed by the age of 13 and 14 years, respectively. In the feet, ossification began first in the hallucal sesamoids at the age of 8 years in females and 9 years in males and was completed by the age of 10 years in both sexes. The incidence and ossification of sesamoids in the hands and feet in the Arab population from Bahrain seem to differ considerably from reports in other populations. The clinical significance of our findings is discussed. Clin. Anat. 20:416,423, 2007. © 2006 Wiley-Liss, Inc. [source] |