Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “JOINTS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed2001

The boundaries for joint angles of isocomfort for sitting and standing males based on perceived comfort of static joint postures.

This study presents data for the joint angles of isocomfort (JAI) in sitting and standing males based on perceived comfort ratings for static joint postures maintained for 60 s. The JAI value was defined as a boundary indicating joint deviation (an angle) from neutral posture, within which the perceived comfort for different body joint postures is expected to be the same. An experiment for quantifying perceived comfort ratings was conducted using the free modulus method of magnitude estimation. Based on experimental results, regression equations were derived for each joint posture, to represent the relationships between different levels of joint deviation/joint posture and corresponding normalized comfort scores. The JAI values were developed for nine verbal categories of joint comfort. The JAIs with the marginal comfort levels, one of the nine verbal categories used, for most joint postures around the wrist, elbow, neck and ankle were similar to the maximum range of motion (ROM) values for these joints. However, the JAIs with the marginal comfort category for back and hip postures were much smaller than the maximum ROM values for these joints. There were no significant differences in JAI expressed in terms of the percentage of the corresponding maximum ROM values between sitting and standing postures. The relative 'marginal comfort index', defined as the percentage of JAIs for the marginal comfort relative to the corresponding maximum ROM values, for the hip was the smallest among all joints. This was followed, in an increasing order of the marginal comfort index, by the lower back and shoulder, while the marginal comfort index for the elbow joint was the largest. The results of this study suggest that static postures maintained for 60 s cause greater discomfort for the hip joint than for the other joints studied, and less discomfort for the elbow than for the other joints. The data about JAIs can be used as guidelines for enhancing postural comfort when designing a variety of human-machine tasks where static postures cannot be eliminated.

Adult↗
PubMed2000

The forelimb in walking horses: 2. Net joint moments and joint powers.

The objective was to measure the net joint moments and joint powers for the joints of the equine forelimb during the walk. Videographic and force data were combined with morphometric information using an inverse dynamics method. During stance phase the predominant joint moment was on the palmar aspect of all forelimb joints except the shoulder, where the peak moment was considerably higher than at any other joint. The entire forelimb showed net energy absorption in both stance and swing phases. The elbow was the only joint that showed net generation of energy, which was used to maintain the limb in extension in early stance as the horse's body vaults over the limb and to drive protraction and retraction of the limb during swing. The carpus aligned the limb into a supportive strut, but did not play an important role in energy absorption or generation. A small burst of positive work on the flexor aspect at the start of breakover indicated that the carpus played an active role in initiating breakover during walking. The fetlock functioned elastically to store and release strain energy during stance. The coffin joint acted as an energy damper during most of stance with a small burst of energy generation on the flexor aspect as the joint flexed during breakover. The magnitude of the peak joint power during swing decreased in a proximal to distal sequence. It is concluded that the elbow joint is the main site of energy generation. The shoulder and coffin joints act as energy dampers during stance. The distal joints had very low joint powers and appeared to be driven by inertial forces during the swing phase. This information will be applied to describe how horses compensate for different lamenesses in terms of redistributing the functions of energy generation and absorption between joints.

Animals↗
PubMed1992

Temporomandibular joint sounds: correlation to joint structure in fresh autopsy specimens.

In an attempt to better understand the cause of different types of temporomandibular joint (TMJ) sounds, we recorded joint sounds from 27 fresh autopsy specimens, displayed the time frequency distribution of the sound as a three-dimensional graph, and correlated the sound character to morphologic observations at subsequent dissection. Eleven joints elicited sounds, and 16 joints were silent. All joints with sounds had different degrees of intraarticular changes. These ranged from disk displacement with reduction to displacement without reduction and arthrosis of the articular surfaces. Reciprocal clicking occurred both in joints with disk displacement with and without reduction, as well as in joints with arthrotic changes. Crepitation only occurred in joints with arthrosis and perforation. The sample was too small to demonstrate any statistically significant association between the joint sound classified as clicking or crepitation and joint structure types of joint pathosis in this small sample. A high frequency component to the sound appeared to be associated with arthrosis of the articular surfaces. It was concluded that joint sounds indicate joint abnormality but that the absence of joint sound does not exclude intraarticular pathosis.

Aged↗
PubMed2003

Ranking systems for evaluation of joint and joint motion stressfulness based on perceived discomforts.

This study aims to develop ranking systems for evaluation of the stressfulness of joints and joint motions based on perceived discomforts measured through an experiment. Twenty healthy male subjects participated in the experiment, where discomforts for varying joint motions in the sitting and standing postures were measured using the magnitude estimation. The results showed that the perceived discomforts were affected by the type of joint motions, size of joint motions, and joints. The joints and joint motions were classified into several distinct classes according to perceived stresses. Three ranking systems based on the perceived discomforts were developed, including classification by the joint motions and joints, by types of joint motions, and by the joints only. The ranking systems revealed that while hip and back motions exhibited higher discomfort ratings than any other joint motion, elbow motions were the least stressful of all joint motions. The ranking systems can be used as a valuable design guideline when ergonomically designing or evaluating workplaces, or as a helpful tool for understanding adverse effects of poor working postures.

Adult↗
PubMed2000

Net joint moments and joint powers in horses with superficial digital flexor tendinitis.

OBJECTIVE: To determine whether analysis of net joint moments and joint powers is a suitable technique for evaluation of mechanics and energetics of lameness in horses and to measure effects of superficial digital flexor tendinitis. ANIMALS: 6 sound horses. PROCEDURE: Horses were evaluated before (sound evaluation) and after (lame evaluation) induction of superficial digital flexor tendinitis in 1 forelimb by injection of collagenase. Recordings were made with an optoelectronic system and a force plate as horses trotted. Net joint moments and joint powers in the sagittal plane at each joint in the forelimbs during the stance phase were determined. Peak values were determined, and mechanical energy absorbed and generated at each joint was calculated. Comparisons were made between contralateral limbs during sound and lame evaluations. RESULTS: Lame limbs had significant reductions in peak values for net joint moments on the palmar aspect of metacarpophalangeal (fetlock), carpal, and humeroulnar joints. Total energy absorbed was significantly lower at every joint in lame limbs, compared with compensating limbs. CONCLUSIONS AND CLINICAL RELEVANCE: Horses with superficial digital flexor tendinitis had significant differences between lame and compensating limbs for net joint moments and joint powers at all joints, indicating that the gait of horses with superficial digital flexor tendinitis is energetically inefficient. Assessment of net joint moments and joint powers is a useful tool in evaluating equine lameness.

Animals↗
PubMed2001

The hindlimb in walking horses: 2. Net joint moments and joint powers.

The objective of the study was to describe net joint moments and joint powers in the equine hindlimb during walking. The subjects were 5 sound horses. Kinematic and force data were collected synchronously and combined with morphometric information to determine net joint moments at each hindlimb joint throughout stance and swing. The results showed that the net joint moment was on the caudal/plantar side of all hindlimb joints at the start of stance when the limb was being actively retracted. It moved to the cranial/dorsal side around 24% stride at the hip and stifle and in terminal stance at the more distal joints. It remained on the cranial/dorsal side of all joints during the first half of swing to provide active limb protraction, then moved to the caudal/plantar aspect to reverse the direction of limb motion prior to ground contact. The hip joint was the main source of energy generation throughout the stride. It was assisted by the tarsal joint in both stance and swing phases and by the fetlock joint during the stance phase. The coffin joint acted as an energy damper during stance, whereas the stifle joint absorbed almost equal amounts of energy in the stance and swing phases. The coffin and fetlock joints absorbed energy as the limb was protracted and retracted during the swing phase, suggesting that their movements were driven by inertial forces. Future studies will apply these findings to detect changes in the energy profiles due to specific soft tissue injuries.

Animals↗
PubMed1996

Characterization of anatomic communications between the femoropatellar joint and lateral and medial femorotibial joints in cattle, using intra-articular latex, positive contrast arthrography, and fluoroscopy.

OBJECTIVE: To evaluate the frequency of communication between the lateral and medial femorotibial joints and the femoropatellar joint in cattle. DESIGN: 1 of 3 injection sites was randomly assigned to each ox. ANIMALS: 102 limbs were obtained from 55 fresh bovine cadavers presented for necropsy with problems unrelated to the stifle. PROCEDURE: The joints were injected with a mixture of latex and barium sulfate. Communication between 2 or more joints was determined by the presence of latex and contrast material in a joint adjacent to the injected joint by examining frozen sections and positive-contrast arthrography. RESULTS: Communication between the 3 joints was present in 58 (56.9%) limbs. The femoropatellar and the medial femorotibial joints always communicated. Thirteen of 38 (34.2%) specimens injected in the lateral femorotibial joint did not communicate with the 2 other joints. The femoropatellar joint communicated with the lateral and medial femorotibial joints on the distal abaxial aspect of the trochlear ridge. CONCLUSION: Individual anatomic variation of the stifle in cattle should be considered when diagnostic or treatment protocols are established. CLINICAL RELEVANCE: The lateral femorotibial joint should be treated separately because it does not consistently communicate with the femoropatellar or medial femorotibial joint.

Animals↗
PubMed2004

Initiation of degenerative joint damage by experimental bleeding combined with loading of the joint: a possible mechanism of hemophilic arthropathy.

OBJECTIVE: To investigate the effect of a limited number of experimental joint bleedings, combined with loading of the affected joint, on the development of progressive degenerative joint damage. METHODS: The right knee of 8 mature beagle dogs was injected with freshly collected autologous blood 3 times per week for 4 weeks, to mimic a limited number of joint hemorrhages occurring over a short period. To ensure loading of the experimental joint, the contralateral control knee of the animals was fixed to the trunk 4 hours per day, 3 days per week. Ten weeks after the last injection, cartilage tissue and synovium were collected from both knees to analyze features of joint degeneration. Cartilage was prepared for analysis of proteoglycan turnover (synthesis, retention, release, and content) and histologic features. Synovium was prepared for histologic analysis. RESULTS: The rate of proteoglycan synthesis was significantly increased, characteristic of degenerative cartilage damage as seen in osteoarthritis. Release of newly formed proteoglycans (as a measure of retention) and total loss of proteoglycans from the cartilage matrix were increased. Cartilage matrix integrity was adversely altered, as shown by histologic damage. Histologic analysis also revealed signs of synovial inflammation. These effects were not observed 10 weeks after the experimental bleedings in joints that did not undergo forced loading. CONCLUSION: Experimental joint bleedings when combined with loading of the affected joint resulted in features of progressive degenerative joint damage, whereas similar joint hemorrhages without joint loading did not. This might reflect a possible mechanism of joint damage in hemophilia.

Animals↗
PubMed1993

Knee joint contact pressure decreases after chronic meniscectomy relative to the acutely meniscectomized joint: a mechanical study in the goat.

Several studies have shown that meniscectomy causes an immediate, acute increase in knee joint contact pressure and that changes in pressure distribution cause remodeling of bone and soft tissue. Presumably, this remodeling in turn affects contact pressures. This study tested the hypothesis that medial compartment contact pressure increases immediately after medial meniscectomy and then decreases with time. Supporting hypotheses regarding medial compartment contact area and lateral compartment pressures also were tested. Unilateral medial meniscectomy was performed on seven adult goats. Four or 8 months later, contact pressure and area were measured in vitro in the involved joints, as well as in the contralateral joints, before and after removal of the meniscus. The medial compartment pressures of the chronically meniscectomized joints were significantly less than those of the acutely meniscectomized paired joints but remained significantly greater than those of the intact joints. For the 4 and 8 month groups combined, the mean pressures of the acutely and chronically meniscectomized joints were greater than the pressures of the paired intact joints by 70 and 42%, respectively. The mean medial compartment contact areas of the acute and chronic joints were lower than those of the intact joints by 60 and 50%, respectively; mean lateral compartment pressures remained the same. This study indicates that joint remodeling reduces joint contact pressures. It also suggests that the effectiveness of a treatment to reduce pressure concentrations may be determined only by comparison, at the same postoperative time, of the pressure with that of the chronically meniscectomized joint, since pressures decreased with time without treatment.

Animals↗
PubMed1999

Tumour necrosis factor-alpha mediates carrageenin-induced knee-joint incapacitation and also triggers overt nociception in previously inflamed rat knee-joints.

Tumour necrosis factor-alpha (TNF alpha) was studied in the carrageenin (CG) induced knee-joint incapacitation, and also in mediating recurrent incapacitation response in knee-joints previously exposed to an inflammatory attack. CG or TNF alpha intra-articular injection into CG-primed knee-joints induced an intense and long-lasting (>8 h) peaking incapacitation response. TNF alpha injected in naive joints did not elicit incapacitation. Anti-TNF alpha serum in situ treatment specifically inhibited CG-induced incapacitation in naive joints, and also TNF alpha-induced incapacitation in primed joints. Hoe-140 (D-Arg0[Hyp3,Thi5,D-Tic7,Oic8]-bradykinin, a bradykinin B2 receptor antagonist, given before CG, abolished incapacitation, but was without effect when injected 3 h after. Hoe-140 given before or after the CG injection in primed joints was without effect, but it produced a partial inhibitory effect in the early phase (1 h) of TNF alpha-induced incapacitation. Des-Arg9[Leu3]-bradykinin, a bradykinin B1 receptor antagonist, given intra-articularly after CG or TNF alpha, reversed incapacitation either in naive or primed joints. Indomethacin abolished the incapacitation induced by CG in naive joints, but only the 5-lipoxygenase inhibitor MK-886 plus indomethacin blocked the response in primed joints. MK-886 did not modify CG-induced incapacitation in naive joints, but lately reversed CG-induced incapacitation in primed joints, and blocked TNF alpha-induced response. Substance P or prostaglandin E2 did not induce incapacitation in either naive or primed joints. Our results support the conclusion that TNF alpha is a mediator of CG-induced inflammatory incapacitation, and is able to induce the further release of kinins and leukotrienes, which is suggested to have an important role in the maintenance of long-lasting nociceptive response.

Animals↗
PubMed1996

[Carpal joint inflammation in calves--treatment by joint resection].

A surgical method of treating purulent inflammation of the carpal joint in calves is reported. This method involves the opening of the diseased joint and the complete removal of diseased tissues (articular resection). Of five calves with various inflammations of the carpal joint and surrounding tissues, four could be successfully treated using this procedure. Following the complete removal of the antebrachiocarpal, middle carpal and/or carpometacarpal, or of all carpal joints, these joints ossified. The range of motion of the carpal joint was limited to various degrees, depending on the position and number of ossified joints. The motility of the limb was little affected in all gait types following the ossification of one joint (the antebrachiocarpal or middle carpal joint) or of two joints (middle carpal and carpometacarpal joints). Goose-stepping was seen in the limb after ossification of all the carpal joints. One calf with highly advanced inflammatory alterations in the carpal joint could not be healed, since it was not possible to completely resect the affected tissues.

Animals↗
PubMed2001

Temporomandibular disorders: relationship between joint pain and effusion and nitric oxide concentration in the joint fluid.

OBJECTIVES: To evaluate the relationship between joint effusion, contrast enhancement of effusion, nitric oxide concentration in TMJ fluid and TM joint pain. METHODS: Nonenhanced T1- and T2-weighted and gadolinium-enhanced T1-weighted spin-echo sequences were performed in 77 patients with TMD. The nitric oxide concentration in TMJ fluid was analysed spectrophotometrically by the Griess reaction. RESULTS: Some or marked effusion was seen in five (9%) of the 56 asymptomatic joints and in 55 (56%) of the 98 symptomatic joints. The prevalence of contrast enhancement of joint effusion was significantly higher in the joint pain group than in the joint sound or asymptomatic joint groups (chi2 test, P<0.001). On postcontrast T1-weighted images, there was no evidence of synovial proliferation in patients with TMD. Anterior disk displacement without reduction was detected in 93% of the TMJs with marked effusion. The degree of joint pain correlated with raised nitric oxide concentration (Spearman's rank correlation, P<0.05). CONCLUSIONS: Painful joints are more likely to demonstrate contrast enhancement of joint effusion. Nitric oxide concentration in TMJ fluid is closely associated with inflammatory changes and painful TM joints.

Adolescent↗
PubMed2006

A robot-assisted study of intrinsic muscle regulation on proximal interphalangeal joint stiffness by varying metacarpophalangeal joint position.

The tightness of intrinsic hand muscles is a common cause of finger joint stiffness. The purposes of this study were to develop a robot-assisted methodology to obtain torque-angle data of a finger joint, and to investigate the regulation of the intrinsic muscles on finger joint stiffness. Our robot system features the integration of a low payload robot arm, a controller, and a force/torque transducer. The system provided highly reproducible torque-angle curves. Torque-angle data of the proximal interphalangeal joint with the metacarpophalangeal joint at 0 and 60 degrees were obtained from eight asymptomatic hands. The torque-angle curve shifted with the position of the metacarpophalangeal joint. As the metacarpophalangeal joint flexion angle changed from 60 to 0 degrees, the equilibrium of the proximal interphalangeal joint increased more than 20 degrees, and joint stiffness increased more than 50%. The dependence of the stiffness of the proximal interphalangeal joint on metacarpophalangeal joint position supports the regulatory role of the intrinsic muscles on finger joint mechanics. This regulatory mechanics is likely amplified in hands with intrinsic muscle tightness, justifying the commonly used Bunnell Intrinsic Tightness Test.

Adult↗
PubMed1996

Kinematics of the trapeziometacarpal joint: a biomechanical analysis comparing tendon interposition arthroplasty and total-joint arthroplasty.

The kinematics of the trapeziometacarpal joint were studied in 15 cadaver hands; normal joints were compared with simulated arthroplasties-either a total-joint arthroplasty of the ball-and-socket variety or a fibrous suspension arthroplasty of ligament reconstruction with tendon interposition. The motion of the thumb metacarpal was analyzed based on a trapezial coordinate system, using a magnetic tracking system. The pivot point (instantaneous center of rotation) for the thumb metacarpal changed during active and passive circumduction. Compared with normal trapeziometacarpal joint motion, the pivot point after ligament reconstruction with tendon interposition shifted significantly in palmar and ulnar directions in reference to the trapezial coordinate system, whereas after total-joint arthroplasty, the pivot point shifted slightly palmarly and radially. The axes of rotation were also compared for ligament reconstruction with tendon interposition and total-joint arthroplasty during thumb flexion-extension and abduction-adduction motions. After ligament reconstruction with tendon interposition, the center of flexion-extension shifted palmarly and the center of abduction-adduction shifted ulnarly. After total-joint arthroplasty, the center of rotation for flexion-extension shifted distally and palmarly and that for abduction-adduction shifted palmarly and proximally. In comparison with the normal joint, passive circumduction increased after tendon interposition arthroplasty but was less with total-joint arthroplasty. Changes in kinematics suggest a suspensory ligament function of ligament reconstruction with tendon interposition arthroplasty, whereas total-joint arthroplasty results in axes of rotation that reflect the joint replacement rather those of the normal joint.

Arthroplasty↗
PubMed2000

[The joint capsule of the cricoarytenoid joint: biomechanical and clinical aspects].

BACKGROUND: Impaired movement of the cricoarytenoid joint with hoarseness and immobility of the vocal ligament may occur as a consequence of laryngeal trauma and joint disease. Little is known to date about the cricoarytenoid joint capsule and its role in joint pathology. METHODS: The present study analyses the structure of the cricoarytenoid joint capsule by means of histological, immunohistochemical, and scanning electron microscopical methods. Investigations are performed on larynges of 17 male and 16 female. RESULTS: The cricoarytenoid joint was found to be lined by a wide and lax joint capsule consisting of a fibrous and a synovial membrane. The capsule was strengthened posteriorly by the cricoarytenoid ligament. As like the fibrous membrane the cricoarytenoid ligament consisted mainly of collagen types I and III. Moreover the ligament was found to be rich in elastic fibers. Unexpected large and intensively vascularized synovial folds projected into the joint cavity. CONCLUSION: The capsule of the cricoarytenoid joint can be compared with the joint capsules of the limbs despite its structure and its involvement in joint pathology. Based on the laxity of the joint capsule it was concluded that invasive interventions at the respiratory tract with dislocation of the arytenoid cartilage can lead to incarceration of the synovial folds. After a trauma aero-synovitis or formation of hemarthrosis may occur, with subsequent fixation of the arytenoid in an abnormal position.

Adult↗
PubMed1998

Function of stiff joints may be restored by Ilizarov joint distraction.

Three patients with joint stiffness caused by trauma or infection are reported. The involved joints are the interphalangeal joint of the thumb, patellofemoral joint, and ankle joint. As an alternative for the indicated arthrodesis in these patients, treatment with articulating joint distraction was performed. By use of adapted Ilizarov external ring fixators, gradual distraction was applied to loosen the joint, followed after loosening by a period of exercise during distraction. In all three patients this experimental approach led to a decrease in pain and improvement of joint function that persisted for at least 2 years after treatment. With the use of Ilizarov joint distraction, joint function in cases of joint stiffness may be restored, and the need for an arthrodesis can be postponed.

Adolescent↗
PubMed2006

Anterior sonography of glenohumeral joint in patients with inflammatory joint disease.

Ultrasonography (US) was shown as an effective imaging modality in evaluating the shoulder. The shoulder joint is probably the most accessible joint for sonography in adults. However, inflammatory changes of the shoulder have received too little attention in US studies. Anterior access for US assessment of glenohumeral joint (GHJ) has not been investigated. Another problem of patients with acute synovitis of glenohumeral joint is the difficulty to perform a 90 degrees abduction for the axillary US because of severe pain and active and passive limitation. We offer the anterior access for assessment of glenohumeral joint synovitis (GHS). Sonographic evaluation (Sonosite-Titan) was carried out in 25 patients with acute GHS and 15 healthy controls. The diagnosis of GHS was made after the patients underwent physical examination and the laboratory evidence was obtained. We used the anterior position of transducer applied laterally to coracoid processus along the anterior joint cavity. The problem of anterior joint cavity investigation in neutral position is a poor presentation of the joint and the application of the biceps tendon. The problem is simply resolved after supination of the hand and external rotation of the shoulder. We measured and compared upper, middle, and lower width of the anterior GHJ cavity. Echogenicity of joint cavity was assessed by comparison with adjacent tissues. Homogeneity and regularity of GHJ cavity was designated in both groups as well. We measured labrum-infraspinatus distance on posterior view for assessment of GHJ synovitis. All cases of GHJ synovitis were confirmed by a US Doppler study. US investigation of healthy controls enabled to find normal values of the width of the anterior GHJ cavity that was less than 7.4 mm. The synovitis group showed GHJ cavity expansion: 8.3+/-2.4 (p=0.001) and 10.5+/-3.1 (p<0.001) for the middle and the lower anterior part of the GHJ respectively. The upper part width was not different in synovitis and control groups. Anterior joint cavity extension to 7.4 mm and upper in its lower part was high sensitive (96%) and specific (86%) US sign of synovitis with the test power above 0.9. The posterior labrum-infraspinatus extension had high specificity for synovitis (100%), but only seven of 25 patients (28%) had increased (>2 mm) the value of the labrum-infraspinatus dimension, which was previously proposed as the US sign of synovitis. Echogenicity of the anterior joint cavity in healthy controls was moderately high (far more echogenic than deltoid muscle). Echogenicity of synovitis declined, and mild effusions were found to be common. Those were not to be seen on US of GHJ in neutral position and were revealed only in supination and external rotation of the shoulder. Intra-articular tissue of healthy controls was relatively echo-homogenic compared with nonhomogenic one of the synovitis group. Bone irregularity was found in patients with long-standing GHJ synovitis reflecting erosive process. A certain position of the shoulder and good knowledge of the normal anterior joint cavity parameters enabled us to diagnose synovitis by anterior shoulder sonography, with the patients experiencing minimal pain during movements.

Case-Control Studies↗