搜索结果：Shoulder & elbow

BACKGROUND: The American Shoulder and Elbow Surgeons (ASES) questionnaire was developed to provide a standardized method for evaluating shoulder function. Previous studies have determined the clinical responsiveness of this outcome measure for heterogenous populations or patients with nonoperatively treated rotator cuff disease. Currently, to our knowledge, no studies exist that establish the clinically relevant change in the ASES score after shoulder arthroplasty. QUESTIONS/PURPOSES: We asked: (1) What are the minimal clinically important difference (MCID) and substantial clinical benefit (SCB) for the ASES score after primary and reverse shoulder arthroplasties? (2) Are the MCID and SCB for the ASES score different between primary and reverse shoulder arthroplasties? (3) What patient-related factors are associated with achieving the MCID and SCB after total shoulder arthroplasty and reverse shoulder arthroplasty? METHODS: A longitudinally maintained institutional shoulder arthroplasty registry was retrospectively queried for patients who underwent primary shoulder arthroplasty, including anatomic or reverse total shoulder arthroplasty from 2007 to 2013, with a minimum 2-year followup. Seven hundred ninety-four patients were identified and eligible; 304 of these patients did not have 2 years of followup or complete datasets, resulting in a study cohort of 490 patients (62% of the 794 potentially eligible). The MCID and SCB of the ASES score for these patients was calculated using an anchor-based method, using four different anchors measuring satisfaction with work, activities, overall, and activity from the SF-36. The MCID (anchored to somewhat satisfied) and SCB (very satisfied) of the ASES score were calculated for the entire cohort and stratified by arthroplasty type. Multivariate logistic regression of patient-related factors that influence the MCID and SCB achievement was performed. RESULTS: The MCID for all patients combined ranged from 6.3 to 13.5; for the overall satisfaction anchor, the MCID was 13.5 ± 4.5 (95% CI, 4.8-22.3). The SCB for the overall cohort ranged from 12.0 to 36.6; for the overall satisfaction anchor, the SCB was 36.6 ± 3.8 (95% CI, 29.1-44.1). There were no differences in the MCID of the ASES score between anatomic and reverse shoulder arthroplasty for any of the anchors (p = 0.159-0.992) or the SCB for any of the anchors (p = 0.467-0.977). Combining anatomic and reverse shoulder arthroplasty in one group, higher preoperative ASES score (odds ratio [OR], 0.96; 95% CI, 0.94-0.98; p < 0.001), having a reverse shoulder arthroplasty (OR, 0.36; 95% CI, 0.16-0.85; p = 0.016), and having rheumatoid arthritis were independent predictors of not achieving an MCID for the ASES 2 years after surgery. Higher preoperative ASES score (OR, 0.91; 95% CI, 0.89-0.92; p < 0.001), a diagnosis of rotator cuff tear arthropathy (OR, 0.14; 95% CI, 0.07-0.30; p < 0.001), a diagnosis of back pain (OR, 0.42; 95% CI, 0.24-0.71); p = 0.002), and living alone (OR, 0.36; 95% CI, 0.19-0.69; p = 0.002) were all independent predictors of not achieving SCB after shoulder arthroplasty. CONCLUSIONS: Patients with glenohumeral arthritis or rotator cuff tear arthropathy who undergo primary conventional total or reverse shoulder arthroplasty and have at least a nine-point improvement in their ASES score experience a clinically important change, whereas those who have at least a 23-point improvement in their ASES score experience a substantial clinical benefit. High preoperative function was associated with a decreased likelihood of achieving clinically important change after total shoulder arthroplasty. LEVEL OF EVIDENCE: Level III, therapeutic study.

BACKGROUND: The overhead throwing athlete has unique range of motion characteristics of the shoulder and elbow. Numerous theories exist to explain these characteristics; however, the precise cause is not known. Although it is accepted that range of motion is altered, the acute effect of baseball pitching on shoulder and elbow range of motion has not been established. HYPOTHESIS: There will be a reduction in passive range of motion immediately after baseball pitching. STUDY DESIGN: Controlled laboratory study. METHODS: Sixty-seven asymptomatic male professional baseball pitchers participated in the study. Passive range of motion measurements were recorded using a customized bubble goniometer for shoulder external rotation, shoulder internal rotation, total shoulder rotational motion, elbow flexion, and elbow extension on the dominant and nondominant arms. Testing was performed on the first day of spring training. Measurements were taken before, immediately after, and 24 hours after pitching. RESULTS: A significant decrease in shoulder internal rotation (-9.5 degrees), total motion (-10.7 degrees), and elbow extension (-3.2 degrees) occurred immediately after baseball pitching in the dominant shoulder (P<.001). These changes continued to exist 24 hours after pitching. No differences were noted on the nondominant side. CONCLUSION: Passive range of motion is significantly decreased immediately after baseball pitching. This decrease in range of motion continues to be present 24 hours after throwing. High levels of eccentric muscle activity have previously been observed in the shoulder external rotators and elbow flexors during pitching. These eccentric muscle contractions may contribute to acute musculotendinous adaptations and altered range of motion. The results of this study may suggest a newly defined mechanism to range of motion adaptations in the overhead throwing athlete resulting from acute musculoskeletal adaptations, in addition to potential osseous and capsular adaptations.

BACKGROUND: Range of motion deficits in shoulder external rotation (ER), internal rotation (IR), total rotation range of motion (ER + IR), and horizontal adduction (HA) have been retrospectively associated with overhand athletes' arm injuries. HYPOTHESIS: The authors expected the incidence of upper extremity injury in high school softball and baseball players with side-to-side shoulder range of motion deficits to be greater than the incidence of upper extremity injury in players with normal shoulder range of motion. STUDY DESIGN: Cohort study (prognosis); Level of evidence, 2. METHODS: High school softball and baseball players (N = 246) participated. Before the start of the season, passive shoulder ER, IR, and HA were assessed at 90° of abduction with the scapula stabilized. Relative risk (RR) was calculated to examine range of motion measure, by categorical criteria, and risk of upper extremity injury. RESULTS: Twenty-seven shoulder and elbow injuries (9 softball, 18 baseball) were observed during the season. The dominant shoulder of all injured players and baseball players displayed a significant decrease in HA (P = .05) and IR (P = .04). The dominant shoulder total rotation of injured baseball players displayed a significant decrease (mean difference = 8.0° ± 0.1°; P = .05) as compared with the dominant shoulder of uninjured baseball players. Players who displayed a decrease of ≥25° of IR in the dominant shoulder were at 4 times greater risk of upper extremity injury compared with players with a <25° decrease in IR, especially for baseball players. While we observed a 1.5 to 2 times increased risk of injury for the 10° to 20° loss in rotational range of motion for the overall sample and baseball, the risk estimates were not statistically significant (P > .05). CONCLUSION: There are large mean deficits in shoulder IR and HA between injured and noninjured players, but not in ER or total rotation. Passive shoulder IR loss ≥25° as compared bilaterally was predictive of arm injury. Shoulder range of motion deficits differed between sports and appeared more predictive of injury for baseball players.

Moving the arm is complicated by mechanical interactions that arise between limb segments. Such intersegmental dynamics cause torques applied at one joint to produce movement at multiple joints, and in turn, the only way to create single joint movement is by applying torques at multiple joints. We investigated whether the nervous system accounts for intersegmental limb dynamics across the shoulder, elbow, and wrist joints during self-initiated planar reaching and when countering external mechanical perturbations. Our first experiment tested whether the timing and amplitude of shoulder muscle activity account for interaction torques produced during single-joint elbow movements from different elbow initial orientations and over a range of movement speeds. We found that shoulder muscle activity reliably preceded movement onset and elbow agonist activity, and was scaled to compensate for the magnitude of interaction torques arising because of forearm rotation. Our second experiment tested whether elbow muscles compensate for interaction torques introduced by single-joint wrist movements. We found that elbow muscle activity preceded movement onset and wrist agonist muscle activity, and thus the nervous system predicted interaction torques arising because of hand rotation. Our third and fourth experiments tested whether shoulder muscles compensate for interaction torques introduced by different hand orientations during self-initiated elbow movements and to counter mechanical perturbations that caused pure elbow motion. We found that the nervous system predicted the amplitude and direction of interaction torques, appropriately scaling the amplitude of shoulder muscle activity during self-initiated elbow movements and rapid feedback control. Taken together, our results demonstrate that the nervous system robustly accounts for intersegmental dynamics and that the process is similar across the proximal to distal musculature of the arm as well as between feedforward (i.e., self-initiated) and feedback (i.e., reflexive) control. NEW &amp; NOTEWORTHY Intersegmental dynamics complicate the mapping between applied joint torques and the resulting joint motions. We provide evidence that the nervous system robustly predicts these intersegmental limb dynamics across the shoulder, elbow, and wrist joints during reaching and when countering external perturbations.

BACKGROUND: Joint pain is thought to be an early sign of injury to a pitcher. OBJECTIVE: To evaluate the association between pitch counts, pitch types, and pitching mechanics and shoulder and elbow pain in young pitchers. STUDY DESIGN: Prospective cohort study. METHODS: Four hundred and seventy-six young (ages 9 to 14 years) baseball pitchers were followed for one season. Data were collected from pre- and postseason questionnaires, injury and performance interviews after each game, pitch count logs, and video analysis of pitching mechanics. Generalized estimating equations and logistic regression analysis were used. RESULTS: Half of the subjects experienced elbow or shoulder pain during the season. The curveball was associated with a 52% increased risk of shoulder pain and the slider was associated with an 86% increased risk of elbow pain. There was a significant association between the number of pitches thrown in a game and during the season and the rate of elbow pain and shoulder pain. CONCLUSIONS: Pitchers in this age group should be cautioned about throwing breaking pitches (curveballs and sliders) because of the increased risk of elbow and shoulder pain. Limitations on pitches thrown in a game and in a season can also reduce the risk of pain. Further evaluation of pain and pitching mechanics is necessary.

To study abnormal spatial patterns of muscle activation in hemiparetic stroke, we compared EMG activity in paretic and contralateral elbow and shoulder muscles of 10 hemiparetic subjects during 1.5-s voluntary isometric contractions, against five to eight different loads. Isometric forces were generated in eight directions, referenced to a plane orthogonal to the long axis of the forearm, and were recorded by a three degrees of freedom load cell, mounted at the wrist. Surface and intramuscular EMGs of six elbow and six shoulder muscles were recorded from both impaired and contralateral upper extremities of each subject. The spatial characteristics of EMG activation of individual muscles were summarized using two measures. The first, called the 'net resultant EMG vector' is a new measure which calculated the vector sum of EMG magnitudes for each of the eight directions, and the second, index of EMG focus, is a measure of the range of EMG activation recorded for each load level. Use of these measures permitted us to describe spatial EMG characteristics quantitatively, which has not been done previously. We observed consistent and statistically significant shifts in the resultant EMG vector directions in the impaired limb, especially in shoulder and other proximal muscles. Significant increases in the angular range of EMG activity were also identified and were most evident at the elbow. Correlation analysis techniques were used to assess the degree of coactivation of different muscle pairs. There were consistent EMG coactivation patterns observed across all subjects (both normal and hemiparetic). However, in spasticparetic limbs, additional novel coactivational relationships were also recorded, especially between elbow flexors/shoulder abductors and elbow extensors/shoulder adductors. These novel coactivation patterns represent a reduction in the number of possible muscle combinations, or in the number of possible 'synergies' in the paretic limb of the stroke subject. This reduction in number of 'synergies' could result from a loss of descending command options; from an increased reliance on residual, descending brainstem pathways (such as the reticulospinal and vestibulospinal projections); from changes in spinal interneuronal excitability; or from a combination of several of these factors. The relative merits of these hypotheses are addressed.

PURPOSE: Previous studies among young pitchers have focused on the frequency and description of elbow injuries. The purpose of this study was to evaluate the frequency of elbow and shoulder complaints in young pitchers and to identify the associations between pitch types, pitch volume, and other risk factors for these conditions. METHODS: A prospective cohort study of 298 youth pitchers was conducted over two seasons. Each participant was contacted via telephone after each game pitched to identify arm complaints. Generalized estimating equations were used to assess associations between arm complaints and independent variables. RESULTS: The frequency of elbow pain was 26%; that of shoulder pain, 32%. Risk factors for elbow pain were increased age, increased weight, decreased height, lifting weights during the season, playing baseball outside the league, decreased self-satisfaction, arm fatigue during the game pitched, and throwing fewer than 300 or more than 600 pitches during the season. Risk factors for shoulder pain included decreased satisfaction, arm fatigue during the game pitched, throwing more than 75 pitches in a game, and throwing fewer than 300 pitches during the season. CONCLUSION: Arm complaints are common, with nearly half of the subjects reporting pain. The factors associated with elbow and shoulder pain were different, suggesting differing etiologies. Developmental factors may be important in both. To lower the risk of pain at both locations, young pitchers probably should not throw more than 75 pitches in a game. Other recommendations are to remove pitchers from a game if they demonstrate arm fatigue and limit pitching in nonleague games.

Abstract Introduction Prolonged physical exposure during smartphone usage results in poor posture causing pain in neck, shoulder, elbow, and hands. So, our aim was to investigate the effect of smartphone addiction on musculoskeletal pain. Methods This cross-sectional study was carried out by a random sampling method from recognized institute in Bangladesh and India. Three hundred twenty-six participants, including male and female, aged between 18 and 30 years participated in this study. Candidates were requested to fill-up a performa containing demographics, Smartphone addiction scale-short form (SAS-SF), Shoulder pain and disability index (SPADI), Neck disability index (NDI), Oxford elbow score (OEC), and Cornell Hand Discomfort Questionnaire (CHDQ). Results The mean age were 22.58 ± 3.19 years, weight 60 ± 11.30 kg, height 162.83 ± 9.74 cm, and body mass index (BMI) of the participants were 22.69 ± 4.36 kg/m 2 . 43.3% participants reported neck pain, 42.9% shoulder pain, and 27.9% reported pain on their elbow while prolonged smartphone use. There was major difference in NDI ( p = 0.047), SPDI ( p = 0.005), OES ( p = 0.002), and CHDQ ( p = &lt; 0.001) among Bangladeshi and Indian population. The SAS has a significant association with NDI; p &lt; 0.001, SPDI; p &lt; 0.001, OES; p &lt; 0.001, and CHDQ; p &lt; 0.001. Conclusion Smartphone addiction negatively impacted and positively related with the musculoskeletal pain in neck, shoulder, elbow, and hand. Care should be given towards the proper use of smartphone and increase public awareness regarding the negative consequences of this serious issue.

Fastball pitches of eight intercollegiate varsity baseball pitchers were filmed using the direct linear transformation (DLT) method of three-dimensional cinematography. Coordinate data were obtained, and the resultant joint forces and torques at the shoulder and elbow joints were calculated. Various kinematic parameters were also calculated to help describe the motions of the shoulder and elbow joints throughout the pitch. At the instant of stride foot contact, a horizontal adduction torque was present at the shoulder joint, and the shoulder was externally rotating. After the onset of the horizontal adduction torque, abduction and internal rotation torques were also present at the shoulder joint and a varus torque was present at the elbow joint. After the instant of maximum external rotation (30 ms prior to ball release), the upper arm started to internally rotate, but it was still in a position of external rotation at the instant of release. This paper discusses the roles of the torques in producing the observed motions of the throwing arm.

Section I: ATLAS 1: Anatomy of Upper Extremity Joints with Cadaveric Correlation Aurea Mohana Borges and Christine B. Chung Section II: TECHNICAL CONSIDERATIONS 2: Technical Considerations for MRI of Upper Extremity Joints Lynne S. Steinbach, Christine B. Chung, and Hiroshi Yoshioka Section III: SHOULDER 3: Clinical Evaluation of the Painful Shoulder John P. Belzer and Frederic W. Bost 4: MR Imaging of the Rotator Cuff Lynne S. Steinbach 5: MRI of Glenohumeral Instability Lynne S. Steinbach 6: Long Bicipital Tendon Including SLAP Lesions Christine B. Chung and Lynne Steinbach 7: Miscellaneous Conditions of the Shoulder Lina Chen and Christine B. Chung 8: The Post Operative Shoulder Luis S. Beltran, William B. Morrison, and Aurea V.R. Mohana-Borges Section IV: ELBOW 9: Clinical Evaluation of the Painful Elbow Christina R. Allen and Marc R. Safran 10: Elbow Ligaments and Instability Christine B. Chung 11: Elbow Tendons and Epicondylitis Christine B. Chung 12: Bone and Cartilage Injury Tudor Hughes and Christine B. Chung 13: Miscellaneous Disorders of the Elbow Christine B. Chung Section V: WRIST AND HAND 14: Clinical Evaluation of the Painful Wrist and Hand McPherson S. Beall, III and Edward Diao 15: Wrist Ligaments and the Triangular Fibrocartilage Complex Hiroshi Yoshioka 16: The Carpal Tunnel and Guyon's Canal David Malfair 17: Miscellaneous Conditions of the Wrist Geoffrey Riley and Lynne Steinbach 18: MR Imaging of Finger Ligaments Christine B. Chung and Rodrigo Aguiar 19: MR Imaging of Finger Tendons Christine B. Chung and Rodrigo Aguiar 20: Miscellaneous Disorders of the Finger Christine B. Chung

OBJECTIVE: This study aimed to decode shoulder, elbow and wrist dynamic movements continuously and simultaneously based on multi-channel surface electromyography signals, useful for electromyography controlled exoskeleton robots for upper-limb rehabilitation. METHODS: Ten able-bodied subjects and ten stroke subjects were instructed to voluntarily move the shoulder, elbow and wrist joints back and forth in a horizontal plane with an exoskeleton robot. The shoulder, elbow and wrist movements and surface electromyography signals from six muscles crossing the joints were recorded. A set of three parallel linear-nonlinear cascade decoders was developed to continuously estimate the selected shoulder, elbow and wrist movements based on a generalized linear model using the anterior deltoid, posterior deltoid, biceps brachii, long head triceps brachii, flexor carpi radialis, and extensor carpi radialis muscle electromyography signals as the model inputs. RESULTS: The decoder performed well for both healthy and stroke populations. As movement smoothness decreased, decoding performance decreased for the stroke population. CONCLUSION: The proposed method is capable of simultaneously and continuously estimating multi-joint movements of the human arm in real-time by characterizing the nonlinear mappings between muscle activity and kinematic signals based on linear regression. SIGNIFICANCE: This may prove useful in developing myoelectric controlled exoskeletons for motor rehabilitation of neurological disorders.

The angular displacements necessary for 70% correct detection were determined in normal subjects at the shoulder and elbow joints and at the terminal joint of the middle finger. Angular velocities of displacement between 0.125 degrees and 160 degrees/s were tested. Each joint was tested in the mid-range of its normal excursion. The joints were carefully supported for testing and the muscles acting at the joints were relaxed. When assessed in terms of angular displacements and angular velocities, proprioceptive performance at the shoulder and elbow joints was superior to that at the finger joint. Optimal performance at the finger joint was attained over the range of angular velocities from 10 degrees to 80 degrees/s. Optimal performance at both more proximal joints was optimal over a wider range (2 degrees-80 degrees/s). Active pointing movements made without vision of the moving part were performed at each joint at velocities within the range of optimal proprioceptive performance. However, when detection levels and displacement velocities were expressed in terms of linear displacements and velocities at the finger tip for all three joints, the finger joint gave the best performance and the shoulder the worst. In practical terms, therefore, displacements of a given linear extent are best detected if they move distal joints and worst if they move proximal joints. For the elbow and finger joints the detection level and velocity data were expressed also in terms of proportional changes in the lengths of muscles operating at these joints, and as proportional changes in the distance between the points of attachment of the joint capsules. Analysis in terms of proportional changes of muscle length showed remarkably similar performance levels at both joints. This suggests that intramuscular receptors are important determinants of proprioceptive performance. Analysis in terms of joint capsular displacement did not unify the data: on this form of analysis proprioceptive performance at the elbow joint was superior.

Wearable inertial systems have recently been used to track human movement in and outside of the laboratory. Continuous monitoring of human movement can provide valuable information relevant to individuals' level of physical activity and functional ability. Traditionally, orientation has been calculated by integrating the angular velocity from gyroscopes. However, a small drift in the measured velocity leads to increasing integration error over time. To compensate that drift, complementary data from accelerometers are normally fused into tracking systems using the Kalman or extended Kalman filter. In this study, we combine kinematic models designed for control of robotic arms with state-space methods to continuously estimate the angles of human shoulder and elbow using two wearable inertial measurement units. We use the unscented Kalman filter to implement the nonlinear state-space inertial tracker. Shoulder and elbow joint angles obtained from 8 subjects using our inertial tracker were compared to the angles obtained from an optical-tracking reference system. On average, there was an RMS angle error of less than 8° for all shoulder and elbow angles. The average correlation coefficient for all movement tasks among all subjects was r ≥ 0.95 . This agreement between our inertial tracker and the optical reference system was obtained for both regular and fast-speed movement of the arm. The same method can be used to track movement of other joints.

Many studies have demonstrated that muscle activity 50-100 ms after a mechanical perturbation (i.e., the long-latency stretch response) can be modulated in a manner that reflects voluntary motor control. These previous studies typically assessed modulation of the long-latency stretch response from individual muscles rather than how this response is concurrently modulated across multiple muscles. Here we investigated such concurrent modulation by having participants execute goal-directed reaches to visual targets after mechanical perturbations of the shoulder, elbow, or wrist while measuring activity from six muscles that articulate these joints. We found that shoulder, elbow, and wrist muscles displayed goal-dependent modulation of the long-latency stretch response, that the relative magnitude of participants' goal-dependent activity was similar across muscles, that the temporal onset of goal-dependent muscle activity was not reliably different across the three joints, and that shoulder muscles displayed goal-dependent activity appropriate for counteracting intersegmental dynamics. We also observed that the long-latency stretch response of wrist muscles displayed goal-dependent modulation after elbow perturbations and that the long-latency stretch response of elbow muscles displayed goal-dependent modulation after wrist perturbations. This pattern likely arises because motion at either joint could bring the hand to the visual target and suggests that the nervous system rapidly exploits such simple kinematic redundancy when processing sensory feedback to support goal-directed actions.

OBJECTIVES: This prospective study concentrated on determining factors of computer work that predict musculoskeletal symptoms in the shoulder, elbow, and low-back regions. METHODS: A questionnaire on ergonomics, work pauses, work techniques, and psychosocial and work factors was delivered to 5033 office workers at baseline in early 1999 (response rate 69%) and to 3361 respondents at the time of the follow-up in late 2000 (response rate 77%). An increased frequency or intensity of symptoms was the outcome variable, including only nonsymptomatic respondents from the baseline questionnaire (symptom frequency below 8 days within the last 12 months or intensity score below 4 within the last 3 months). RESULTS: In the follow-up, 10%, 18%, and 23% had symptoms more often in the elbow, shoulder, and low back, respectively, and 14%, 20%, and 22% had more intense symptoms. Women were more likely to be afflicted than men in all regions. In the full-fit multivariate logistic regression analysis, little influence on the timing of a rest pause and being disturbed by glare or reflection were significant predictors of shoulder symptoms, screen below eye height was a significant predictor for elbow symptoms, and previous symptoms was a significant predictor for symptoms in all regions. Computer worktime and psychosocial dimensions were not significant predictors. CONCLUSIONS: Influence on work pauses, reduction of glare or reflection, and screen height are important factors in the design of future computer workstations. Since previous symptoms was a significant predictor of recurrent symptoms in all three regions under study, it can be concluded that musculoskeletal symptoms are persistent.

The loss of range of motion (ROM) in the upper extremities can interfere with activities of daily living (ADL) and, therefore, many interventions focus on improving impaired ROM. The question, however, is what joint angles are needed to naturally perform ADL. The present review aimed to compile and synthesize data from literature on shoulder and elbow angles that unimpaired participants used when performing ADL tasks. A search was conducted in PubMed, Cochrane, Scopus, CINAHL, and PEDro. Studies were eligible when shoulder (flexion, extension, abduction, adduction) and/or elbow (flexion, extension) angles were measured in unimpaired participants who were naturally performing ADL tasks, and angles were provided per task. Thirty-six studies involving a total of 66 ADL tasks were included. Results demonstrated that unimpaired participants used up to full elbow flexion (150°) in personal care, eating, and drinking tasks. For shoulder flexion and abduction approximately 130° was necessary. Specific ADL tasks were measured often, however, almost never for tasks such as dressing. The synthesized information can be used to interpret impairments on the individual level and to establish rehabilitation goals in terms of function and prevention of secondary conditions due to excessive use of compensatory movements.

OBJECTIVE: To determine the most sensitive scoring method for assessment of rheumatoid arthritis (RA) disease activity using the American College of Rheumatology Core Data Set. METHODS: The subjects were 4,530 patients with RA (mean age 57.9 years, mean disease duration 12.7 years) who participated in a large observational cohort study of RA patients. The 68 joints assessed were classified into 15 joint areas, and each joint variable was categorized based on the presence or absence of swelling or pain in these areas. Multiple linear regression and analysis of variance were used to evaluate the significance of effects of these 15 joint areas on variables for assessment of RA disease activity such as patient's assessment of pain on a visual analog scale (VAS), patient's and physician's global assessment of disease activity on a VAS, HAQ (Health Assessment Questionnaire), and Japanese HAQ. RESULTS: Although the 3 most frequently affected joints were the wrist, metacarpophalangeal joints, and proximal interphalangeal joints, the 5 joints with the largest contributions to all of the variables assessed for disease activity were the shoulder, elbow, and knee joints, followed by the wrist and ankle joints. The combination of shoulder, elbow, and knee joints accounted for approximately 70% of the contribution to all the variables, while addition of the wrist and ankle joints increased this value to approximately 90%. CONCLUSION: Scoring for assessment of RA disease activity would be more sensitive if separate joints such as the shoulder, elbow, knee, wrist, and ankle joints were weighted differently.

The purpose of the study was to examine the resultant joint forces (RJFs) and torques (RJTs) at the shoulder, elbow, and wrist during penalty throws and determine the relationships between muscle actions and motions of the throwing arm. Subjects with an overhand (OH) throwing technique created larger maximal and average RJTs at the shoulder and elbow compared to subjects with a sweep (SW) technique (Feltner &amp; Nelson, 1996). Prior to release, OH technique subjects decreased their abduction torque and created adduction torques at the shoulder. Adduction torques and downward vertical motion of the trunk, together with an internal rotation torque at the shoulder, resulted in large internal rotation angular velocities at release for the OH technique subjects. The SW technique subjects did not exhibit these technique characteristics. Additionally, throwing technique exhibited a moderate but positive relationship with several chest, upper arm, and forearm circumference measures. Findings suggest that muscular strength may be a causal determinant of technique style.

BACKGROUND: Joint injections and aspirations are used to reduce joint pain and decrease inflammation. The efficacy of these injections is diminished when they are placed inadvertently in the wrong location or compartment. The purpose of this study was to determine whether the use of varying sites or imaging techniques affects the rate of accurate needle placement in aspiration and injection in the shoulder, elbow, and knee. HYPOTHESES: (1) Accuracy rates of different joint injection sites will demonstrate variability. (2) Injection accuracy rates will be improved when performed with concomitant imaging. STUDY DESIGN: Systematic review of the literature. METHODS: Studies reporting injection accuracy based on image verification were identified through a systematic search of the English literature. Accuracy rates were compared for currently accepted injection sites in the shoulder, elbow, and knee. In addition, accuracy rates with and without imaging of these joints were compared. RESULTS: In the glenohumeral joint, there is a statistically higher accuracy rate with the posterior approach when compared with the anterior approach (85% vs 45%). Injection site selection did not affect accuracy for the subacromial space, acromioclavicular joint, elbow, or knee. The use of imaging improved injection accuracy in the glenohumeral joint (95% vs 79%), subacromial space (100% vs 63%), acromioclavicular joint (100% vs 45%), and knee (99% vs 79%). CONCLUSION: Injection accuracy rates are significantly higher for the posterior approach compared with the anterior approach for the glenohumeral joint. Similarly, the accuracy rates are also higher when imaging is used in conjunction with injection of the glenohumeral joint, subacromial space, acromioclavicular joint, and knee.