Carpal bone movements in gripping action of the giant panda (Ailuropoda melanoleuca)

The movement of the carpal bones in gripping was clarified in the giant panda ( Ailuropoda melanoleuca ) by means of macroscopic anatomy, computed tomography (CT) and related 3-dimensional (3-D) volume rendering techniques. In the gripping action, 3-D CT images demonstrated that the radial and 4th carpal bones largely rotate or flex to the radial and ulnar sides respectively. This indicates that these carpal bones on both sides enable the panda to flex the palm from the forearm and to grasp objects by the manipulation mechanism that includes the radial sesamoid. In the macroscopic observations, we found that the smooth articulation surfaces are enlarged between the radial carpal and the radius on the radial side, and between the 4th and ulnar carpals on the ulnar side. The panda skilfully grasps using a double pincer-like apparatus with the huge radial sesamoid and accessory carpal.     

Radial sesamoid bone as a part of the manipulation system in the lesser panda (Ailurus fulgens).

The well-developed radial sesamoid bone presented a rod-like shape in the lesser panda. It could be separated into two components: (1) an ulnar cartilaginous, (2) a radial osseous part. The radial sesamoid bone was connected with four elements as follows: (1) the tendon of the M. abductor pollicis longus, (2) M. abductor pollicis brevis and M. opponens pollicis, (3) Aponeurosis palmaris, and (4) Flexor retinaculum. The bone made no articulation with the first metacarpal. The movement of the radial sesamoid bone may be controlled by the connecting muscles and muscle-related structures. It is suggested that the bone acts as a supporting ridge in the gripping action in the lesser panda. However, we suggest that the grasping mechanism is obviously different from that of the giant panda, in which the radial sesamoid bone is connected strongly with the first metacarpal.     

Palmar interosseous muscle of the human thumb

The adductor pollicis muscle was studied in fifty hands of Japanese adult cadavers of both sexes. The radial portion of the oblique head of the adductor pollicis muscle has carpal and metacarpal origins and an insertion into the wing tendon of the extensor apparatus. This portion was located dorsal to the palmar metacarpophalangeal articular nerve and superficial palmar metacarpal artery. Thus, the radial portion of the oblique head of the adductor pollicis muscle (more strictly, the slips dorsal to the palmar-penetrating twig of the ulnar nerve) is similar to the palmar interosseous muscles, except that its slips cannot be clearly distinguished from each other.     

Adaptation of the hindlimbs for climbing in bears.

The hindlimbs of the Malayan sun bear (Helarctos malayanus), the polar bear (Ursus maritimus), the brown bear (Ursus arctos) and the giant panda (Ailuropoda melanoleuca) have been anatomically and osteometrically studied. The Musculus tibialis cranialis of the Malayan sun bear and the giant panda possessed a well-developed rich fleshy portion until the distal end of the tibia. In the polar bear and the brown bear, however, the fleshy portion of the M. tibialis cranialis was not developed until the distal end of the tibia. The tendon of the M. tibialis cranialis inserting on the proximal end of the Ossa metatarsalia was shorter in the Malayan sun bear and the giant panda than in the polar bear and the brown bear. In the Malayan sun bear and the giant panda, moreover, the M. popliteus was attached more distally to the tibia than in the polar bear and the brown bear. The stable dorsiflexion and supination of the foot and the efficient pronation of the crus are important for skillful tree climbing. The present study suggests that the Malayan sun bear and the giant panda have hindlimbs especially adapted to tree climbing by the well-developed fleshy portion of the M. tibialis cranialis reaching the distal end of the tibia, its short tendon, and the M. popliteus inserting near the distal end of the tibia.     

Comparative morphology of the muscles of mastication in the giant panda and the Asiatic black bear.

The morphological differences in the muscles of mastication between the giant panda (Ailuropoda melanoleuca) and the Asiatic black bear (Ursus thibetanus) were sought to confirm the adaptational strategy of these muscles in the giant panda. We measured some skull characteristics and weighed the muscles of mastication, and macroscopically observed the muscles of mastication in the two species. The noticeable differences between the two species are classified as follows: (1) The size ratio of the zygomatic width was much larger in the giant panda than in the Asiatic black bear. (2) The weight ratio of the two pterygoid muscles was also much larger in the giant panda than in the Asiatic black bear. (3) The lateral slips of the temporal muscles are thicker and stronger in the Asiatic black bear than in the giant panda. (4) The deep layer of the masseter muscle was rostrocaudally divided, and a complicated running of tendons is observed in the giant panda. (5) The two pterygoid muscles were much larger and well-developed in the giant panda than in the Asiatic black bear. The points (1) and (4) may be related to the generation of the force necessary to chew the bamboo in the giant panda. We thought that the large mass of the masseter and temporal muscles are needed in this species. In the points of (2) and (5), the two pterygoid muscles were obviously different in form and weight ratio between the two species. We suggest that the two pterygoid muscles may act as an additional force generator to dorsoventrally press and crush bamboo stems.     

Hereditary index finger polydactyly: phenotypic, radiological, dermatoglyphic, and genetic findings in a large family.

Index finger polydactyly in a Turkish family is reported. The transmission of the malformation fits the pattern of regular autosomal dominant inheritance. Some of the affected individuals had one or two phalanges on their first digits, but all had triphalangeal second fingers. Subjects with polydactyly had very interesting dermatoglyphs, such as an extra a triradius under the super-numerary index finger, the proximal radiant of this triradius (an extra A-line) ending on the radial border of the hand, and arch tibials in the hallucal areas. The carpal bones, beginning with os multangulum majus, or alternatively with the extra one were articulated with two metacarpals. A similar finding was found in the feet.     

Detailed anatomy of the antebrachiocarpal joint in dogs.

A comparative study of the anatomy of the antebrachiocarpal (AC) articulation was carried out in 30 adult dogs with 60 joints. Although a considerable degree of similarity was found between the AC joint in dogs and the corresponding wrist joint in humans, a number of differences between these two homologous joints were also noted. The distal end of the ulna in dogs directly articulates with the ulnar carpal and accessory carpal bones forming a specialized antebrachiocarpal arrangement more adapted to running. The accessory carpal bone in dogs is a massive, long bone and is strikingly different from its homologue in humans, the pisiform bone. The joint between the accessory and ulnar carpal bones, which corresponds to the piso-triquetral joint in humans, is always connected with the AC joint, whereas in humans this communication could be found occasionally. The large radial carpal bone in dogs, characteristic for carnivores, corresponds to the fused scaphoid and lunate bones in humans, in whom this type of fusion is very rarely found. The palmar ulnocarpal and radiocarpal ligaments in dogs are distinctly intra-articular, whereas in humans these ligaments are intracapsular. One of the controversies of the AC joint in dogs is a structure located between the distal-most parts of the radius and ulna forming a strong bond between these two bones and a part of the antebrachial articular surface. It is cartilage-like and is composed of typical fibrocartilaginous tissue.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detailed anatomy of the antebrachiocarpal joint in dogs

A comparative study of the anatomy of the antebrachiocarpal (AC) articulation was carried out in 30 adult dogs with 60 joints. Although a considerable degree of similarity was found between the AC joint in dogs and the corresponding wrist joint in humans, a number of differences between these two homologous joints were also noted. The distal end of the ulna in dogs directly articulates with the ulnar carpal and accessory carpal bones forming a specialized antebrachiocarpal arrangement more adapted to running. The accessory carpal bone in dogs is a massive, long bone and is strikingly different from its homologue in humans, the pisiform bone. The joint between the accessory and ulnar carpal bones, which corresponds to the piso-triquetral joint in humans, is always connected with the AC joint, whereas in humans this communication could be found occasionally. The large radial carpal bone in dogs, characteristic for carnivores, corresponds to the fused scaphoid and lunate bones in humans, in whom this type of fusion is very rarely found. The palmar ulnocarpal and radiocarpal ligaments in dogs are distinctly intra-articular, whereas in humans these ligaments are intracapsular. One of the controversies of the AC joint in dogs is a structure located between the distalmost parts of the radius and ulna forming a strong bond between these two bones and a part of the antebrachial articular surface. It is cartilage-like and is composed of typical fibrocartilagineous tissue. Considering its location, form, and function, this structure in dogs should be regarded as the articular disc and so-named; it is also concluded that it is a homologue to the articular disc of the distal radioulnar joint in humans. © 1992 Wiley-Liss, Inc.     

Homology of the adductor pollicis and contrahentes muscles: a study of monkey hands

The deep palmar muscles in monkey hands were studied. The contrahentes muscles mainly arose from the capitate bone, descended palmar to the deep palmar branch of the ulnar nerve and the palmar metacarpophalangeal nerves, and attached to the proximal phalanges or wing tendons of the second, fourth and fifth fingers. In relation to the deep palmar branch of the ulnar nerve and the palmar metacarpophalangeal nerves, the contrahentes muscles are homologous with the adductor pollicis and flexor indicis radialis muscles. The contrahentes muscles occasionally gave off some accessory slips which blended with the interosseous muscles. These findings suggest that the human adductor pollicis muscle is a well-developed remnant of a contrahens muscle, and that the human interosseous muscles contain some remnant of the contrahentes muscle. In fact, a well-developed remnant of a contrahens muscle was found in the fourth finger of a human hand. It is further considered that the human adductor pollicis muscle contains an element of the interosseous muscle of the thumb.     

第1掌骨背桡侧岛状皮瓣的应用解剖

目的　提供第1掌骨背桡侧岛状皮瓣的应用解剖依据。 方法　解剖 20具防腐固定成人手标本,观测第1掌背桡侧皮支血管链的起源、外径、长度及吻合。1例新鲜成年手标本动脉造影。 结果　在拇长展肌腱止点深面可见一条粗大皮支起始,39侧来源自桡动脉浅支,1侧来源于桡动脉主干。该皮支主干沿拇短伸肌腱桡侧向远端走行,相距2 mm。在掌指关节平面,与指掌侧动脉穿支吻合。 结论　以第1掌骨背桡侧该皮支为轴心血管设计轴线,切取岛状皮瓣修复手部皮肤软组织缺损在解剖上具有可行性。     

Characteristics of the electrophysiological activity of muscles attached to the transverse carpal ligament in carpal tunnel syndrome

The main cause of carpal tunnel syndrome (CTS) remains unknown. Stiffness of the subcutaneous area of the volar aspect of the carpal tunnel is present in many patients and suggests that the stiffness of muscles attached to the transverse carpal ligament is increased. We performed an electrophysiological study to investigate muscle activities and to clarify whether the stiffness of muscles attached to the transverse carpal ligament is involved in the pathogenesis of CTS. The subjects of this study included 16 patients with early CTS showing no motor dysfunction. Both thenar muscles (opponens pollicis, abductor pollicis brevis, and flexor pollicis brevis) and hypothenar muscles (opponens digiti minimi, abductor digiti minimi, flexor digiti minimi brevis) were investigated. Surface electrodes were placed on each muscle, and maximum voluntary contractions with the thumb and little finger in opposition were maintained for 3 seconds in all patients and in 7 control subjects. Electromyographs were subjected to fast Fourier transform analysis, and the root mean square (RMS) and the mean power frequency (MPF) were determined for each muscle. The RMS of the opponens pollicis was significantly less in hands affected by CTS (292.8 μV) than in healthy hands (405.9 μV). The RMS did not differ between affected hands and healthy hands for the other 2 thenar muscles but did differ significantly for the hypothenar muscles. The MPF did not differ between affected hands and healthy hands for any muscle. The results show that electrophysiological differences are present among muscles innervated by the median nerve and that hypothenar muscles originally unrelated to median nerve dysfunction are also affected in early CTS. These results suggest that modulation of muscles attached to the transverse carpal ligament is involved in the pathogenesis of CTS.     

Anatomical work-up of an individual with multiple muscular variants on both forearms

Muscular variants of the forearm are common and frequently cause neurovascular compression syndromes, especially when interfering with the compact topography of the carpal tunnel or the Canalis ulnaris. Here, we report on a male body donor with multiple muscular normal variations on both forearms. The two main findings are (1) an accessory variant muscle (AVM) on the right forearm originating from the M. brachioradialis, the distal radius, and the M. flexor pollicis longus. It spanned the wrist beneath the Fascia antebrachia and inserted at the proximal phalanx of the digitus minimus. (2) Moreover, we found a three-headed palmaris longus variant on the left arm with proximal origin tendon and a distal, trifurcated muscle belly, with separated insertions at the palmar aponeurosis, the flexor retinaculum, and, in analogy to the accessory muscle on the contralateral arm, at the base of the proximal phalanx of the digitus minimus. We found a considerable thickening of the left-hand median nerve right before entering the carpal tunnel indicative of a possible chronic compression syndrome adding clinical relevance to this anatomical case. We also discuss the notion that both, the AVM and the contralateral three-headed palmaris variant are developmental descendants of the M. palmaris longus. Additionally, we found a previously not recorded variant of the M. palmaris brevis on the left hand.

     

Biomechanical alterations in the carpal arch and hand muscles after carpal tunnel release: A further approach toward understanding the function of the flexor retinaculum and the cause of postoperative grip weakness

The difference between maximal and minimal distance covered (the distance between the trapezium ridge and hamate hook; moment exerted on structures: I Nm) by an intact flexor retinaculum (FR; minimum, 3.3 ± 0.1 cm; maximum, 3.7 ± 0.2 cm) and the increase in the maximal distance on carpal tunnel release (CTR; increase, 1.6 ± 0.2 mm) were significant. Under an external supination moment, the distance between the attachments of the trapeziopisiform band increased after CTR. Under external pronation and ulnar abduction moments, the distance between the attachments of the scaphoideohamate band increased after CTR. The CTR resulted in an anatomic attachment loss for the following muscles: the superficial head of the flexor pollicis brevis (shortening by ∼25%, relative to rest length), the ulnar part of the abductor pollicis brevis (with opposition and adductory functions, ∼20%), the opponens pollicis (∼20%), the middle part of the abductor pollicis brevis (∼7%), and the opponens digiti minimi (∼10%). Preoperative and postoperative (2–7 weeks after surgery) measurements of the reaction force of the distal phalanx (under isometric thumb opposition and finger II–IV flexion with extended carpal joint) led to differentiation of three groups: (1) significant strength loss—the patients showed difficulties with grasping, lifting, twisting off lids and caps, screwing, pulling ropes, and pinching; (2) no significant change in force values; and (3) a significant increase in strength (patients who could grip more firmly). © 1996 Wiley-Liss, Inc.     

Osteosarcoma of the hands and feet: a distinct clinico-pathological subgroup

Osteosarcomas of hands or feet are rare, and seemingly these cases differ in presentation and behavior compared to those in usual locations. The clinico-pathological presentation of patients with osteosarcomas of the hand or foot was studied and compared with published cases. Forty osteosarcomas were identified among 4,221 cases, representing 0.95 % of all osteosarcomas. Thirty of these were well documented. Mean age at diagnosis was 43 years (hands) and 36 years (feet) and male–female ratio was 1.2:1 and 2.0:1, respectively. In the hand, 62 % of the osteosarcomas presented in the metacarpals and 23 % in the phalanges, and only two cases occurred in the carpal bones. Distribution in the foot was tarsal bones 56 %, metatarsal bones 33 %, and phalanges 11 %.Of the cases in the hand 54 % were of high grade and of those in the foot 71 %. Survival of osteosarcomas of the hand or foot was 81 %. Only patients with high-grade osteosarcoma died of the disease. Histological grade was the only significant variable related to survival. High-grade osteosarcoma of the hand or feet should be treated similar to those in conventional sites. Osteosarcomas of hands or feet are rare and in a relative high proportion are of low grade. Survival in high-grade cases is comparable to that in conventional sites.     

正中神经返支卡压及易损伤部位的解剖学基础

目的：探讨腕管综合征术后大鱼际功能恢复不良的原因与返支易损伤部位。方法：对20侧成人新鲜上肢标本进行显微解剖，观测正中神经返支走行中存在的卡压因素以及易损伤部位。结果：(1)拇短屈肌浅头尺侧存在腱弓及腱纤维束结构，对正中神经返支形成卡压；(2)住屈肌支持带远侧返支与掌腱膜关系密切，在此部位掌腱膜可对返支形成卡压或术中易误伤返支；(3)走行中返支与拇长屈肌腱和示指屈肌腱存在交叉走行关系。结论：(1)返支走行中存在易卡压因素，治疗腕管综合征时应常规探查松解返支；(2)涉及拇长屈肌腱，示指屈肌腱和掌腱膜手术时，应注意防止损伤返支。     

Sympathetic pathology evidenced by hand thermal anomalies in carpal tunnel syndrome.

OBJECTIVE: To clarify sympathetic pathology in carpal tunnel syndrome and the usefulness of digital infrared thermography as a diagnostic aid. MATERIAL AND METHODS: 38 clinically diagnosed carpal tunnel syndrome hands from 30 patients (confirmed by the standard nerve conduction studies) and 41 hands from 22 healthy volunteers (the hands having current finger inflammation were excluded) were studied. A series of hand infrared photos of each subject were taken and stored by using the technique of digital infrared thermography. We studied the infrared pictures and measured the temperatures of finger tips from digit 1 (D1) to digit 5 (D5), the center point of thenar (Th) and hypothenar eminences (Ht), then we calculated the temperature differences (absolute values) between each two of the 7 points, and median index (MI): (D1-D2)+(D2-D3)+(D1-D3). The means of D2 and Th (MD2+Th), D5 and Ht (MD5+Ht) were also calculated. RESULTS: The results showed that the temperatures of median nerve distribution area in the hands were highly significantly different (Th-Ht, p < 0.001, MI, p < 0.001) between carpal tunnel syndrome (CTS) and the control group. The differences between the median and ulnar nerve distribution area were also highly significantly different in CTS hands (MD2+Th compared to MD5+Ht, p < 0.01). The sensitivity and specificity of digital infrared thermography were 84 and 91%, respectively. CONCLUSION: Digital infrared thermography suggests sympathetic neural pathology in carpal tunnel syndrome. It may also be useful as an additional non-invasive tool in the diagnosis of CTS especially in the early stage.     

Gene cloning, sequencing, expression and biological activity of giant panda (Ailuropoda melanoleuca) interferon-alpha

The giant panda (Ailuropoda melanoleuca) is an endangered species and indigenous to China. In mammals, multiple subtypes of interferon-alpha (IFN-alpha) exist, most of which possess antiviral activity. Little is known about giant panda IFN-alpha genes and the role they may play in giant panda immunological responses to viruses. We have cloned genes encoding 12 giant panda IFN-alpha (AmIFN-alpha or AmIFNA) subtypes that share from 90 to 99% amino acid sequence identity. AmIFN-alpha12 has one additional amino acid at position 57, which is not present in other subtypes. Sequence identity of the AmIFN-alpha proteins encoded by the 12 genes compared to human IFN-alpha2 is approximately 58%. Unlike most of the human subtypes, each of the 12 giant panda IFN sequences has an N-glycosylation recognition site. Expression of all 12 AmIFN-alpha subtypes in 293 cells was confirmed by SDS-PAGE and Western blotting analysis. The antiviral activity and antiproliferative activity of each AmIFN-alpha subtype produced in transiently transfected 293 cell cultures were tested in vitro. All AmIFN-alpha subtypes were found to be stable at pH 2 or 65 degrees C and to exhibit antiviral activity. Some IFN subtypes (AmIFN-alpha8 and AmIFN-alpha4) showed higher biological activity levels than others, whereas AmIFN-alpha11 exhibited lower activity. AmIFN-alpha had various antiproliferative activities to different target cells. To B16 cells, AmIFN-alpha3, AmIFN-alpha4, AmIFN-alpha8 had the highest activities, while to K562 cells, AmIFN-alpha3, AmIFN-alpha7, AmIFN-alpha10 had the highest activities. The various IFN-alpha subtypes displayed a good correlation between their antiviral and antiproliferative potencies.     

Collateral arterial pathways in the forearm

We studied the forearm vessels and the palmar carpal arch in 41 fresh cadaver upper limbs injected with colored latex solutions. In one case, we found a complete occlusion of the radial artery. Collateralization was evident through the anterior interosseous artery, its palmar branch and the radial part of the palmar carpal arch. The diameters of these vessels were significantly enlarged. The dissections of the remaining 40 arms demonstrated that these vessels offer a possible collateralization pathway via the anterior interosseous artery. One hypothesis for the formation of such collateralization might be a dominant blood flow of the radial artery to the hand. Therefore, it seems sensible to preserve the communication between the anterior interosseous and the radial arteries through the palmar carpal arch, raising the radial artery for surgery.     

Human Membrane-bound C3 Receptors I. Serological and Immunohistological Demonstration of C3 Receptors

The aim of the present study was to present further evidence of the specific reactivity of an anti-C3 receptor serum (AC3RS), to demonstrate membrane-bound C3 receptors by using this AC3RS in different serological and immunohistological methods, and to investigate the relationship between membrane-bound C3 receptor and α₁-antitrypsin. The AC3RS, or F(ab)₂ fragments of the IgG fraction of this antiserum, stained a percentage on various viable cell populations roughly equivalent to the number of cells that bound EAC3b and or EAC3d; C3 receptor-negative T cells and thymocytes were not stained. On frozen sections of tonsils and kidneys it was found that the AC3RS stained the area to which EAC3b adhered. After absorption with neutrophils or E_hu, the AC3RS Inhibited the agglutination of EAC3d with tonsil cells, not the agglutination of tonsil cells or neutrophils with EAC3b; this absorbed AC3RS still stained tonsil cells but not neutrophils, in frozen tonsil sections it Stained only those areas to which AC3d adhered. The absorbed AC3RS did not stain glomeruli. Antisera to α₁-antitrypsin failed to in-hibit EAC agglutination with C3 receptor-bearing cells or to stain C3 receptor-positive cells either in suspension or in frozen sections. Absorption of the AC3RS with purified α₁-antitrypsin did not affect its specific reactivity.