Elbow Joint (elbow + joint)

Distribution by Scientific Domains


Selected Abstracts


Biomechanics of the Fractured Medial Coronoid Process and the Isolated Anconeal Process in the Canine Elbow Joint

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
J. Maierl
Introduction:, Elbow dysplasia is one of the most important orthopaedic diseases of the canine elbow joint. The medial coronoid process (MCP) and the anconeal process (AP) are involved with a high incidence. Aims:, The aim of this study was to clarify whether these processes are especially loaded resulting in osteoarthrosis. Material and Methods:, Elbow joints were examined from dogs of various breeds, with a body weight over 20 kg and an age ranging from 1 to 12 years. Only joints without damage to the articular cartilage have been included in this investigation. Articular surfaces have been evaluated macroscopically, subchondral bone density (long-term loading) and split-lines (long-term tensile loading) have been determined. Results:, In the humeral fossa olecrani, there was a distinct impression on the inner side of the lateral compared to the medial epicondyle. In the ulna, the MCP was much greater than the lateral coronoid indicating that the medial process has to support the humeral condyle to a higher extent. Subchondral split lines with a transverse orientation in the fossa olecrani gave evidence of long-term transverse tensile loading in this area. Split lines on the MCP were oriented radially as if the lateral edge was bent downwards. Subchondral bone density in the fossa olecrani was higher towards the lateral epicondyle in comparison to the medial. Furthermore, there was a bone density maximum on the medial part of the humeral condyle opposite of the MCP with its very high density. Discussion:, Gait analyses showed that there is a transverse, medially oriented force of up to 4% bodyweight acting on the paw during midstance. As the carpus is stable when slightly hyperextended during midstance loading there is a long lever arm from the ground up to an assumed rotation centre in the depth of the trochlear notch. The medially directed ground reaction force slightly rotates the forearm inwards causing a bending moment about the elbow joint, which leads to an increased pressure of the AP and the MCP. This bending in addition to sagittal loading is the reason for the high susceptibility of the MCP and AP. [source]


The ligamentum olecrani of the Elbow Joint in Dogs and Cats

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
E. Engelke
The olecranon ligament (ligamentum olecrani) is described as an elastic ligament of the elbow joint in carnivores that tenses the caudomedial part of the joint capsule. The aim of the study was to compare the course and the microscopic structure of the ligament in dogs and cats. The elbow regions of 25 dogs and 15 cats were dissected to examine the topography of the ligament in extension and flexion. Furthermore, the olecranon ligaments of five dogs and five cats were studied using routine histological methods. Additional sections were stained with Resorcin,Fuchsin and Orcein to detect elastic fibres. In both species the olecranon ligament originates at the lateral surface of the epicondylus medialis humeri and inserts at the cranial crest of the olecranon extending distally to the roof of the processus anconeus. Tension of the ligament only occurs when the elbow joint is flexed maximally. This tension is increased by a slight supination of the forearm, which takes place automatically in this joint position. In dogs the ligament is long (30,40 mm in medium sized breeds) and relatively slim (approx. 2,4 mm). In cats the ligament is short (10,12 mm) and relatively strong (5,8 mm). The histological examination of the olecranon ligament shows all signs of a tight collagenous ligament with a negligible amount of elastic fibres. The olecranon ligament helps to limit the maximal flexion of the elbow joint. In addition, it controls a slight lateral movement of the processus anconeus during the automatic supination of the antebrachial bones in extreme flexion of the elbow joint. [source]


Biomechanics of the Fractured Medial Coronoid Process and the Isolated Anconeal Process in the Canine Elbow Joint

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
J. Maierl
Introduction:, Elbow dysplasia is one of the most important orthopaedic diseases of the canine elbow joint. The medial coronoid process (MCP) and the anconeal process (AP) are involved with a high incidence. Aims:, The aim of this study was to clarify whether these processes are especially loaded resulting in osteoarthrosis. Material and Methods:, Elbow joints were examined from dogs of various breeds, with a body weight over 20 kg and an age ranging from 1 to 12 years. Only joints without damage to the articular cartilage have been included in this investigation. Articular surfaces have been evaluated macroscopically, subchondral bone density (long-term loading) and split-lines (long-term tensile loading) have been determined. Results:, In the humeral fossa olecrani, there was a distinct impression on the inner side of the lateral compared to the medial epicondyle. In the ulna, the MCP was much greater than the lateral coronoid indicating that the medial process has to support the humeral condyle to a higher extent. Subchondral split lines with a transverse orientation in the fossa olecrani gave evidence of long-term transverse tensile loading in this area. Split lines on the MCP were oriented radially as if the lateral edge was bent downwards. Subchondral bone density in the fossa olecrani was higher towards the lateral epicondyle in comparison to the medial. Furthermore, there was a bone density maximum on the medial part of the humeral condyle opposite of the MCP with its very high density. Discussion:, Gait analyses showed that there is a transverse, medially oriented force of up to 4% bodyweight acting on the paw during midstance. As the carpus is stable when slightly hyperextended during midstance loading there is a long lever arm from the ground up to an assumed rotation centre in the depth of the trochlear notch. The medially directed ground reaction force slightly rotates the forearm inwards causing a bending moment about the elbow joint, which leads to an increased pressure of the AP and the MCP. This bending in addition to sagittal loading is the reason for the high susceptibility of the MCP and AP. [source]


Evidence from proprioception of fusimotor coactivation during voluntary contractions in humans

EXPERIMENTAL PHYSIOLOGY, Issue 3 2008
Trevor J. Allen
In experiments on position sense at the elbow joint in the horizontal plane, blindfolded subjects were required to match the position of one forearm (reference) by placement of their other arm (indicator). Position errors were measured after conditioning elbow muscles of the reference arm with an isometric contraction while the arm was held either flexed or extended. The difference in errors after the two forms of conditioning was large when the conditioned muscles remained relaxed during the matching process and it became less when elbow muscles were required to lift a load during the match (10 and 25% of maximal voluntary contraction, respectively). Errors from muscle conditioning were attributed to signals arising in muscle spindles and were hypothesized to result from the thixotropic property of passive intrafusal fibres. Active muscle does not exhibit thixotropy. It is proposed that during a voluntary contraction the errors after conditioning are less, because the spindles become coactivated through the fusimotor system. The distribution of errors is therefore seen to be a reflection of fusimotor recruitment thresholds. For elbow flexors most, but not all, fusimotor fibres appear to be recruited by 10% of a maximal contraction. [source]


Successful angiographic embolization of recurrent elbow and knee joint bleeds in seven patients with severe haemophilia

HAEMOPHILIA, Issue 1 2009
R. KLAMROTH
Summary., In haemophilic joints with high-grade arthropathy, bleeds occur that do not respond to replacement therapy of the deficient coagulation factor. The reason may be pathologically reactive angiogenesis in chronic synovitis. Seven patients with severe haemophilia A or haemophilia B experienced recurrent massive bleeds of one elbow joint or knee joint in the absence of trauma. After initial application of factor VIII or IX (fVIII/fIX; 50 IU kg,1 bodyweight), there was only slow and never complete relief of symptoms. Despite intensive secondary prophylaxis maintaining the plasma level of factor concentrate at minimum 50%, new massive bleeds at the same location occurred. Vascular bleeding was suspected. Angiography of the arteries was performed via the femoral artery. Vessels identified as potential bleeding sources were embolized with embolization fluid (ONYX) in eight joints (six elbow and two knee joints). Under low-dose prophylactic treatment (15 IU fVIII or fIX per kg bodyweight for three times per week), no recurrent severe bleed unresponsive to coagulation factor replacement occurred after a mean observation time of 16 months after embolization. The consumption of factor concentrate decreased to one-third of the amount consumed before embolization. In conclusion, angiographic embolization with a non-adhesive liquid embolic agent might be considered as a promising therapeutic and coagulation factor saving option in joint bleeds not responding to replacement of coagulation factor to normal levels. [source]


Variations in the normal anatomy of the collateral ligaments of the human elbow joint

JOURNAL OF ANATOMY, Issue 3 2000
K. S. BECKETT
The variations which occur in the medial and lateral ligament complexes of the elbow were investigated. These occurred frequently with the standard appearances occurring in no more than half the specimens on the medial side and one quarter of those on the lateral side. Surgeons who regularly perform elbow arthroplasty must be aware of these considerations, especially with the introduction of unconstrained prostheses which rely upon the ligament complex for their postoperative stability. [source]


Design of a reconfigurable planar parallel manipulator

JOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 12 2004
R. Fisher
This work presents the design of a reconfigurable planar parallel manipulator (RPPM). The RPPM is designed to act as a testbed manipulator for theories on redundant actuation of parallel manipulators and can reconfigure into three different revolute-jointed mechanism types: a 2-branch 2-DOF (degree-of-freedom) 5-bar mechanism; a 2-branch 3-DOF 6-bar mechanism; and a 3-branch 3-DOF 8-bar mechanism. The design of the RPPM allows for any shoulder or elbow joint to be actuated. In this work, the criteria and constraints of the design are presented. The final design of the RPPM is shown, followed by a discussion of the final design and how it relates to the initial design criteria and constraints. © 2004 Wiley Periodicals, Inc. [source]


The lissamphibian humerus and elbow joint, and the origins of modern amphibians

JOURNAL OF MORPHOLOGY, Issue 12 2009
Trond Sigurdsen
Abstract The origins and evolution of the three major clades of modern amphibians are still a source of controversy, and no general consensus exists as to their relationship to the various known Paleozoic taxa. This may indicate that additional character complexes should be studied to resolve their phylogenetic relationship. The salamander elbow joint has been fundamentally misinterpreted in previous morphological descriptions. In caudates and anurans, both the radius and ulna (fused in anurans) articulate with the characteristically large capitulum (radial condyle), although part of the ulnar articulating surface fits into to the smooth trochlear region. The salamander "ulnar condyle" of previous descriptions is in fact the entepicondyle. The condition seen in batrachians (i.e., salamanders and frogs) may be a lissamphibian synapomorphy because the elbow region of the primitive fossil caecilian Eocaecilia resembles those of frogs and salamanders. In addition to the large and bulbous capitulum, all lissamphibian humeri lack an entepicondylar foramen, and possess a distally pointing entepicondyle, a low and rounded ectepicondyle, and an elongated shaft. These characters are identified in key fossil forms to assess the support for the different hypotheses proposed for the evolutionary origins of lissamphibians. Temnospondyli is the only group of early tetrapods that shows a progressive evolution of lissamphibian traits in the humerus and elbow joint. Furthermore, among Paleozoic taxa, the dissorophoid temnospondyl Doleserpeton annectens is the only taxon that has the full set of humeral features shared by all lissamphibians. These results add support for the theory of a monophyletic origin of lissamphibians from dissorophoidtemnospondyls. J. Morphol., 2009. © 2009 Wiley-Liss, Inc. [source]


Mycobacterium ulcerans infection diagnosed by polymerase chain reaction

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 3 2002
FM Russell
Abstract: Mycobacterium ulcerans infection is the third most important mycobacterial infection world-wide affecting immunocompetent individuals and causes chronic progressive skin ulcers. It has been described in many different regions world-wide. The diagnosis of M. ulcerans infection is often delayed because the diagnosis is difficult to make when new cases appear outside known endemic areas. However, molecular methods are now available to diagnose and distinguish M. ulcerans from other mycobacteria, allowing rapid diagnosis. Presented here is the case of a previously well girl from Townsville, Queensland, with extensive M. ulcerans infection involving the elbow joint, triceps tendon and underlying bone. Rapid diagnosis by polymerase chain reaction confirmed M. ulcerans infection. This is the first known case of M. ulcerans infection from Townsville in over 25 years, highlighting the changing epidemiology of this disease. [source]


Validation of a client-based clinical metrology instrument for the evaluation of canine elbow osteoarthritis

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 6 2009
C. A. Hercock
Objective: To validate a disease-specific client-based clinical metrology instrument (questionnaire) for dogs with chronic osteoarthritis of the elbow joint. Materialsand Methods: This was a prospective cohort study involving 26 dogs with chronic osteoarthritis of the elbow with 24 associated clients. Validity (face and criterion), reliability and responsiveness of the metrology instrument (named "Liverpool Osteoarthritis in Dogs [elbow]") were tested in a sequence of studies. Face validity involved use of international peer review. Reliability was assessed using a test-retest scenario with a two week interval; peak vertical force as measured by a force platform was used as an external standard measure. Responsiveness was tested with a two week, single-blinded placebo-controlled intervention using a licensed non-steroidal anti-inflammatory drug. Results: The reliability of Liverpool Osteoarthritis in Dogs (elbow) in the test-retest scenario was good; intraclass correlation coefficient is 0·89, 95 per cent confidence interval 0·75 to 0·95, compared with intraclass correlation coefficient 0·92, 95 per cent confidence interval 0·74 to 0·98, for peak vertical force. Responsiveness testing indicated that the "net" effect size (allowing for placebo effect) for Liverpool Osteoarthritis in Dogs (elbow) was 0·13 compared with (,)0·18 for the force platform. Criterion validity for Liverpool Osteoarthritis in Dogs (elbow) against peak vertical force was poor; Spearman's rank correlation is ,0·24 (P=0·30). Clinical Significance: Liverpool Osteoarthritis in Dogs (elbow) was considered reliable with satisfactory responsiveness. The poor criterion validity suggests a mismatch between force platform peak vertical force and client perceptions of lameness. This instrument requires further validation in larger studies with alternative client groups and alternative therapeutic interventions, but this initial validation suggests that Liverpool Osteoarthritis in Dogs (elbow) is worthy of continued investigation. [source]


Co-existence of ununited anconeal process and fragmented medial coronoid process of the ulna in the dog

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 2 2006
A. Meyer-Lindenberg
Objectives: To determine the incidence of fragmented medial coronoid process of the ulna in dogs with ununited anconeal process. The efficacy of presurgical radiography to diagnose the co-existence of these diseases was also investigated. Methods: One hundred and fifty-five joints from 137 dogs with ununited anconeal process were included in the study. For the radiographic examinations, an extended mediolateral projection and a craniolateral-caudomedial oblique projection of each elbow joint were taken before surgery. Inspection of the medial part of the joint was carried out either by arthrotomy or arthroscopy. Results: Seventy-two per cent of the dogs were German shepherd dogs. In 25 joints (16 per cent) a fragmented medial coronoid process was diagnosed and removed via arthrotomy or arthroscopy. The co-existence of a fragmented medial coronoid process was diagnosed correctly in only 13 cases (52 per cent) by radiography. In five of these cases with advanced osteoarthritis, the fragment was directly visible because of its dislocation. Compared with published information, the occurrence of ununited anconeal process with fragmented medial coronoid process is noted more frequently in the present study. Clinical Significance: It can be summarised that if ununited anconeal process is present, it is not usually possible to clearly identify fragmented medial coronoid process by radiography. Therefore, it is important to be able to inspect the medial aspect of the joint concerned during surgery. [source]


Reaction time is not impaired by stimulation of the ventral-intermediate nucleus of the thalamus (Vim) in patients with tremor

MOVEMENT DISORDERS, Issue 3 2002
Didier Flament PhD
Abstract We studied the effect of high-frequency electrical stimulation of the ventral-intermediate nucleus of the thalamus (Vim) in four patients implanted with chronic stimulators to determine whether this procedure adversely affects reaction time to a proprioceptive stimulus. Two patients had undergone this surgery for treatment of tremor resulting from Parkinson's disease insufficiently responsive to levodopa therapy and two patients for treatment of essential tremor. Reaction times to auditory, visual, cutaneous, and proprioceptive stimuli were tested in a simple motor task requiring flexion of the elbow joint to a visual target in response to each stimulus. Reaction times were tested postoperatively with and without the stimulator turned on. We found that reaction time for all stimulus modalities was not increased when the stimulator was turned on; in fact, reaction times were, on average, slightly shorter during stimulation, but this difference was not statistically significant. We conclude that transmission of somatosensory inputs, necessary for initiating voluntary movement, from the periphery to the cortex is not significantly impaired by stimulation of the ventral-intermediate nucleus of the thalamus in patients with pathological tremor. © 2002 Movement Disorder Society [source]


Surgical treatment of "terrible triad of the elbow": technique and outcome

ORTHOPAEDIC SURGERY, Issue 2 2010
Yu-xing Wang MD
Objective:, To describe the authors' surgical technique and to evaluate the final functional outcome of surgical treatment of the "terrible triad of the elbow". Methods:, Eight patients identified with "terrible triad" injury patterns, including posterior elbow dislocation, radial head fracture and coronoid fracture, were available for a minimum of 11 months follow-up. Evaluation of functional outcome was based on Mayo elbow performance, Broberg-Morrey scores, and the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Complications were also recorded. Results:, Five elbows redislocated while in a splint after manipulative reduction. Three had residual subluxation after operative treatment. The final mean extent of forearm movement was as follows: 21° of extension deficit (range, 5° to 45°), 126° of flexion (range, 110° to 140°), 75° of supination (range, 45° to 90°), and 71° of pronation (range, 30° to 90°). The mean Mayo, Broberg-Morrey, and DASH scores were 78.0 ± 13.4, 76.0 ± 14.0, and 28.0 ± 24.7, respectively. Conclusions:, When an elbow joint is affected by the terrible triad, it is very unstable and prone to numerous complications. With operative treatment, the surgeon should attempt to perform internal fixation of the coronoid fracture, to regain normal radiocapitellar contact (either by preserving the radial head with open reduction and internal fixation (ORIF) or by replacing it with a prosthesis), and to repair the lateral collateral ligament (LCL). Thus early functional recovery and a successful final functional outcome can be achieved. [source]


Effect of elbow flexion contractures on the ability of people with C5 and C6 tetraplegia to lift

PHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 2 2001
Lisa Harvey
Abstract Background and Purpose It is commonly assumed that minor elbow flexion contractures prevent people with C5,C6 tetraplegia and paralysis of the triceps brachii muscles from bearing full body weight through their upper limbs. The aim of the present study was to determine the effect of simulated bilateral elbow flexion contractures on the ability of these individuals to bear weight through their upper limbs and to determine whether full passive elbow extension is truly critical for lifting body weight. Method A biomechanical study was performed. Body weight lifted was measured under conditions that simulated bilateral elbow flexion contractures. Five people with motor complete C6 tetraplegia and one person with motor complete C5 tetraplegia, all with bilateral paralysis of the triceps brachii muscles, were recruited to the study. Subjects were fitted with bilateral elbow splints that restricted elbow extension but did not restrain elbow flexion nor prevent the elbow from collapsing, and were seated on an instrumented platform that measured vertical forces under the buttocks. Subjects pushed down through their hands and lifted under five different conditions, namely: with no elbow splints; with bilateral elbow splints adjusted to restrict elbow extension by 5,10°; by 15,20°; by 25,30° and with bilateral elbow splints adjusted to allow unrestricted movement of the elbow joint. Maximal weight lifted from under the buttocks, for each condition, was expressed in relation to weight under the buttocks during unsupported sitting (that is, ,seated body weight'). Results Subjects lifted progessively less weight from under their buttocks as passive elbow restriction was progressively restricted. However, one subject lifted all his seated body weight when elbow extension was restricted by 5,10° and another lifted all his seated body weight when elbow extension was restricted by 5,10° and 15,20°. Conclusions Minor elbow flexion contractures will not alone prevent people with tetraplegia and paralysis of the triceps brachii muscles from lifting. Full passive elbow extension is not critical for the performance of this task. Copyright © 2001 Whurr Publishers Ltd. [source]


Biomechanics of the Fractured Medial Coronoid Process and the Isolated Anconeal Process in the Canine Elbow Joint

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
J. Maierl
Introduction:, Elbow dysplasia is one of the most important orthopaedic diseases of the canine elbow joint. The medial coronoid process (MCP) and the anconeal process (AP) are involved with a high incidence. Aims:, The aim of this study was to clarify whether these processes are especially loaded resulting in osteoarthrosis. Material and Methods:, Elbow joints were examined from dogs of various breeds, with a body weight over 20 kg and an age ranging from 1 to 12 years. Only joints without damage to the articular cartilage have been included in this investigation. Articular surfaces have been evaluated macroscopically, subchondral bone density (long-term loading) and split-lines (long-term tensile loading) have been determined. Results:, In the humeral fossa olecrani, there was a distinct impression on the inner side of the lateral compared to the medial epicondyle. In the ulna, the MCP was much greater than the lateral coronoid indicating that the medial process has to support the humeral condyle to a higher extent. Subchondral split lines with a transverse orientation in the fossa olecrani gave evidence of long-term transverse tensile loading in this area. Split lines on the MCP were oriented radially as if the lateral edge was bent downwards. Subchondral bone density in the fossa olecrani was higher towards the lateral epicondyle in comparison to the medial. Furthermore, there was a bone density maximum on the medial part of the humeral condyle opposite of the MCP with its very high density. Discussion:, Gait analyses showed that there is a transverse, medially oriented force of up to 4% bodyweight acting on the paw during midstance. As the carpus is stable when slightly hyperextended during midstance loading there is a long lever arm from the ground up to an assumed rotation centre in the depth of the trochlear notch. The medially directed ground reaction force slightly rotates the forearm inwards causing a bending moment about the elbow joint, which leads to an increased pressure of the AP and the MCP. This bending in addition to sagittal loading is the reason for the high susceptibility of the MCP and AP. [source]


The ligamentum olecrani of the Elbow Joint in Dogs and Cats

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
E. Engelke
The olecranon ligament (ligamentum olecrani) is described as an elastic ligament of the elbow joint in carnivores that tenses the caudomedial part of the joint capsule. The aim of the study was to compare the course and the microscopic structure of the ligament in dogs and cats. The elbow regions of 25 dogs and 15 cats were dissected to examine the topography of the ligament in extension and flexion. Furthermore, the olecranon ligaments of five dogs and five cats were studied using routine histological methods. Additional sections were stained with Resorcin,Fuchsin and Orcein to detect elastic fibres. In both species the olecranon ligament originates at the lateral surface of the epicondylus medialis humeri and inserts at the cranial crest of the olecranon extending distally to the roof of the processus anconeus. Tension of the ligament only occurs when the elbow joint is flexed maximally. This tension is increased by a slight supination of the forearm, which takes place automatically in this joint position. In dogs the ligament is long (30,40 mm in medium sized breeds) and relatively slim (approx. 2,4 mm). In cats the ligament is short (10,12 mm) and relatively strong (5,8 mm). The histological examination of the olecranon ligament shows all signs of a tight collagenous ligament with a negligible amount of elastic fibres. The olecranon ligament helps to limit the maximal flexion of the elbow joint. In addition, it controls a slight lateral movement of the processus anconeus during the automatic supination of the antebrachial bones in extreme flexion of the elbow joint. [source]


Elbow joint luxation in a 1-month-old foal

AUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2008
LM Rubio-Martínez
This paper reports on luxation of the elbow joint without concomitant fracture in a 1-month-old foal. Conservative treatment, with closed reduction and full-limb bandaging, including caudal and lateral splints, seemed successful initially, however, failed to provide enough stability and luxation recurred, and open reduction and surgical placement of prosthetic collateral ligaments was required. Luxation of the elbow joint should be considered when acute non-weight bearing forelimb lameness occurs associated with pain and swelling in the area of the elbow in young foals. Closed reduction failed to provide sufficient joint stability. [source]


Intraneural ganglion cyst: A 200-year-old mystery solved

CLINICAL ANATOMY, Issue 7 2008
Robert J. Spinner
Abstract We describe the first reported case of an intraneural ganglion cyst, an ulnar ("cubital") intraneural cyst, which, on literature review, dated to 1810. For over 80 years, its original brief description by Beauchêne was wrongly attributed to Duchenne, effectively making the reference and specimen inaccessible to scrutiny. Fortunately, the intact cyst had been safely housed in the Musée Dupuytren, Paris, France, thus permitting its examination. Although originally described as a "serous" cyst, our present understanding of the anatomy of the ulnar nerve and of peripheral nerve pathology allowed us to reinterpret it as a mucin-filled, elbow-level, ulnar intraneural ganglion cyst. In addition to its description as a fusiform cystic enlargement of the nerve, we documented similar enlargement of a lumen-bearing branch, the articular branch at the level of the elbow. Based on our assessment of the specimen and with a modern perspective, we concluded that the origin of the cyst was from the postero-medial aspect of the elbow joint and that its fluid content, having dissected through a capsular defect, followed the path of the articular branch into the parent ulnar nerve. The purpose of this report is to clarify historical misconceptions regarding the pathogenesis of this controversial entity. Clin. Anat. 21:611,618, 2008. © 2008 Wiley-Liss, Inc. [source]


Functional anatomy and muscle moment arms of the thoracic limb of an elite sprinting athlete: the racing greyhound (Canis familiaris)

JOURNAL OF ANATOMY, Issue 4 2008
S. B. Williams
Abstract We provide quantitative muscle,tendon architecture and geometry data for the racing greyhound thoracic limb. Muscle mass, belly length, fascicle lengths, pennation angles and moment arms were measured, as were tendon masses and lengths. Maximum isometric force and maximum power were estimated for muscles, and maximum stress and strain were estimated for tendons. Results are compared with other fast quadrupedal runners, and to previously published data in mixed-breed dogs. The implications of the functional adaptations of the greyhound thoracic limb for sprinting performance are discussed. The thoracic limb was found to benefit from a similar proportion of locomotor muscle mass to the pelvic limb, suggesting that it may be used to some extent in propulsion, or alternatively that stabilisation is very important in this animal. Extrinsic muscles, especially latissimus dorsi and pectoralis profundus, were predicted to be powerful and important for generating net positive work during accelerations. Proximal biarticular muscles show specialisation toward preventing collapse of the shoulder and elbow joints to enable strut-like limb function, or some form of dynamic control. Distal muscles did not appear specialised for elastic energy storage, a functional difference to pelvic limb muscles, and the equivalents in horse thoracic limbs. The greyhound thoracic limb appears to possess substantial differences from both that of more ,sub-maximal specialist' quadrupeds, and from the greyhound pelvic limb. [source]