In this issue of JOSPT, the Orthopaedic Section of the American Physical Therapy Association introduces the first of its shoulder clinical practice guidelines (CPGs), titled "Shoulder Pain and Mobility Deficits: Adhesive Capsulitis." This CPG, as well as the collection of Orthopaedic Section CPGs previously published in JOSPT, use long diagnostic labels to identify the underlying clinical conditions. Author Paula M. Ludewig discusses the merits of using these movement system diagnostic labels rather than shorter pathoanatomic labels, which create a disconnect between diagnostic and treatment processes.

J Orthop Sports Phys Ther 2013;43(5):280-283. doi:10.2519/jospt.2013.0104

KEY WORDS: clinical practice guidelines, diagnostic labels, ICF, Orthopaedic Section

This was the third research meeting focused on scapular function and dysfunction, following similar meetings in 2003 and 2006. The purpose of this meeting, hosted by the Shoulder Center of Kentucky, was to continue to examine the biomechanical and clinical factors thought to be associated with the role of the scapula in shoulder function and dysfunction. Since the last Summit, much more information has been created in this area, and it was thought that enough progress had been made that an organized overview of current knowledge could provide some consensus statements to guide further research and provide assessment and treatment guidelines. A call for abstracts was extended to researchers with proven interest and published research on the scapula. The meeting was organized around 3 primary categories of information: scapular kinematics and dysfunction, clinical evaluation of the scapula, and interventions. The last session of the meeting involved development of consensus statements for each category. This document represents the current state of knowledge concerning the aspects of scapular function and dysfunction discussed at the Summit. It is expected that, as more knowledge is developed, the gaps will be filled in and a clearer understanding of the roles of the scapula in shoulder function will emerge. This issue includes the consensus statements and abstracts from the Summit.

J Orthop Sports Phys Ther 2009;39(11):A1-A13. doi:10.2519/jospt.2009.0303

SYNOPSIS: There is a growing body of literature associating abnormal scapular positions and motions, and, to a lesser degree, clavicular kinematics with a variety of shoulder pathologies. The purpose of this manuscript is to (1) review the normal kinematics of the scapula and clavicle during arm elevation, (2) review the evidence for abnormal scapular and clavicular kinematics in glenohumeral joint pathologies, (3) review potential biomechanical implications and mechanisms of these kinematic alterations, and (4) relate these biomechanical factors to considerations in the patient management process for these disorders. There is evidence of scapular kinematic alterations associated with shoulder impingement, rotator cuff tendinopathy, rotator cuff tears, glenohumeral instability, adhesive capsulitis, and stiff shoulders. There is also evidence for altered muscle activation in these patient populations, particularly, reduced serratus anterior and increased upper trapezius activation. Scapular kinematic alterations similar to those found in patient populations have been identified in subjects with a short rest length of the pectoralis minor, tight soft-tissue structures in the posterior shoulder region, excessive thoracic kyphosis, or with flexed thoracic postures. This suggests that attention to these factors is warranted in the clinical evaluation and treatment of these patients. The available evidence in clinical trials supports the use of therapeutic exercise in rehabilitating these patients, while further gains in effectiveness should continue to be pursued. LEVEL OF EVIDENCE: Level 5.

J Orthop Sports Phys Ther. 2009;39(2):90-104. doi:10.2519/jospt.2009.2808

KEYWORDS: acromioclavicular joint, biomechanics, rotator cuff, scapula, shoulder

STUDY DESIGN: Descriptive laboratory study. OBJECTIVES: To determine the 3-dimensional motions occurring between the scapula relative to the clavicle at the acromioclavicular joint during humeral elevation in the scapular plane. BACKGROUND: Shoulder pathology is commonly treated through exercise programs aimed at correcting scapular motion abnormalities. However, little is known regarding how acromioclavicular joint motions contribute to normal and abnormal scapulothoracic motion. METHODS AND MEASURES: Thirty subjects (16 males, 14 females) participated. Subjects with positive symptoms on clinical exam or past history of shoulder pathology, trauma, or surgery were excluded. Electromagnetic surface motion analysis was performed tracking the thorax, clavicle, scapula, and humerus. Subjects performed 3 repetitions of scapular plane abduction. Passive motion data were also collected for scapular plane abduction from cadaver specimens. Data were analyzed using within-session reliability and descriptive statistics as well as repeated measures analyses of variance (ANOVAs) to determine the effect of elevation angle from rest to 90º humeral elevation. Reliability was determined from repeated trials in the same session without removing sensors or redigitizing landmarks. RESULTS: Angular values were highly repeatable within session (ICC>0.94; SEM, < 2.3°). During active scapular plane abduction from rest to 90°, average acromioclavicular joint angular values demonstrated increased internal rotation (approximately 4.3°), increased upward rotation (approximately 14.6°), and increased posterior tilting (approximately 6.7°) (P<.05). Passive motions on cadavers demonstrated similar kinematic patterns.
CONCLUSIONS: Significant motion occurs at the acromioclavicular joint during active humeral elevation, contributing to scapular motion on the thorax. This information provides a foundation for understanding normal acromioclavicular joint motion as a basis for further investigation of pathology and rehabilitation approaches.

J Orthop Sports Phys Ther. 2008;38(4):181-190, published online 7 December 2007. doi:10.2519/jospt.2008.2386

J Orthop Sports Phys Ther. 2006; 36(12):926- 934. doi:10.2519/jospt.2006.2241 

Key Words: biomechanics, rotator cuff, scapula, shoulder

Study Design: Cross-sectional. Objectives: To determine the reliability of a surface sensor measurement of clavicular motion during arm elevation and to describe 3-dimensional clavicular motion in an asymptomatic population. Background: Abnormal scapular motion on the thorax has been implicated in shoulder pathology. Without the ability to measure clavicular motion, it is not possible to identify if abnormal scapular motions derive from the sternoclavicular or acromioclavicular joints. Methods and Measures: Thirty-nine subjects participated in the investigation, including an asymptomatic group (n = 30) and a group with a history or current symptoms of shoulder pathology (n = 9). Clavicular angles relative to the thorax were tracked with surface electromagnetic sensors on the thorax, clavicle, and humerus as subjects completed humeral flexion, scapular plane abduction, and abduction. Within-day reliability was assessed using intraclass correlation coefficients and SEM. Descriptive statistics quantified sternoclavicular joint motions for the various arm movements. Results: Reliable measurements were obtained, with intraclass correlation coefficients ranging from 0.93 to 0.99, and SEMs from 0.9° to 1.8°. Between-day reliability SEM values were generally 2° to 4°. During elevation of the arm, the clavicle with respect to the thorax generally undergoes elevation (11°-15° maximum), retraction (15°-29° maximum), and posterior long-axis rotation(15°-31° maximum), with variability between subjects and planes of motion regarding the magnitude of motion. Conclusion: Rehabilitation approaches attempting to improve shoulder motion should benefit from improved knowledge of 3-dimensional contributions of the clavicle to normal and abnormal scapular kinematics.

J Orthop Sports Phys Ther. 2004;34(3):140-149. doi:10.2519/jospt.2004.1020

Keywords: clavicle, kinematics, shoulder, sternoclavicular joint

Study Design: Repeated-measures analysis of variance. Objective: To examine the effect of 2 different orthotic posting designs on first metatarsophalangeal (first MTP) joint kinematics during gait. Background: Common orthotic designs used to control abnormal pronation incorporate the use of a medial post in the forefoot and/or rearfoot locations. Although this design may favorably alter rearfoot and lower-limb kinematics, the incorporation of a forefoot post has been theorized to negatively impact first MTP joint function by limiting hallux dorsiflexion during push off. An alternative design that has been proposed to be more favorable for function of the hallux and first metatarsal is the medial arch support. Methods and Measures: Eighteen subjects with a mean age of 28.2 years (SD, 8.3 years) completed the study. All subjects were judged to have excessive pronation based on a clinical orthopaedic examination. Two different pairs of orthoses were custom molded for each subject. One design incorporated an extrinsic rearfoot and forefoot post and the second design had a high medial longitudinal arch in combination with an extrinsic rearfoot post. The "Flock of Birds" electromagnetic tracking device was used to collect 3-dimensional position and orientation data of 3 body segments (hallux, first metatarsal, and calcaneus) during the stance phase of walking for 3 conditions (no orthosis and each of the 2 different orthotic designs). A repeated-measures analysis of variance was used to assess differences in first MTP joint dorsiflexion at midstance and during the push-off period of gait, as well as metatarsal declination angle changes during relaxed stance. An exploratory regression analysis was used to investigate factors that related to the change in peak dorsiflexion for the orthotic conditions. Results: Peak first MTP joint dorsiflexion averaged between 38° and 40° across all conditions. Although slight increases in first MTP joint dorsiflexion values were noted with both types of orthotic designs, these differences were not significant at either phase of the stance cycle (P = .50). The metatarsal declination angle in relaxed stance significantly increased (P = .001) under both orthotic conditions. Considerable individual variability was present. For the rearfoot-forefoot posted orthosis, a change in the declination angle of the first metatarsal during relaxed stance with the orthosis was a significant nonlinear predictor of change in peak dorsiflexion during push off. Conclusions: Foot orthoses that incorporate a medial forefoot post do not have a consistent negative effect of reducing first MTP joint dorsiflexion during walking.

J Orthop Sports Phys Ther. 2004;34(6):317-327. doi:10.2519/jospt.2004.1246

Key Words: arch support, first metatarsal joint, hallux, medial orthotic posts

Study Design: Experimental design using 1-way analysis of variance and regression analysis to test the influence of 3 forefoot alignments on the dorsal mobility of the first ray. Objectives: To determine the effect of forefoot alignment on the magnitude of first ray dorsal mobility to an imposed load and to describe any association between forefoot alignment and age on dorsal mobility of the first ray. Background: Instability of the first ray has been implicated as a primary mechanical etiology of many foot problems. It has been proposed that a relationship exists between forefoot alignment and mobility of the first ray, with a varus aligned forefoot contributing to the development of an unstable first ray. Methods and Measures: Sixty female (n = 34) and male (n = 26) subjects aged 18-77 were assigned into valgus, neutral, and varus foot groups (20 per group) based on a clinical measurement of forefoot alignment. A load cell device measured dorsal mobility of the first ray under a standard load of 55 N. Within-day repeat measures were taken from a subsample of subjects. In addition to reliability analysis, analysis of variance and regression analyses tested the relationship between forefoot alignment, age and sex, and mobility of the first ray. Results: The forefoot valgus group demonstrated significantly less dorsal mobility of the first ray than neutral or varus groups. The varus and neutral groups were not significantly different from one another. Forefoot alignment and sex were significant linear predictors (R2 = 0.40) of first ray dorsal mobility. Age had no significant association to dorsal mobility of the first ray. Conclusion: Subjects having a valgus aligned forefoot had less dorsal excursion of the first ray than subjects having a neutral aligned forefoot. This investigation provides evidence supporting a relationship between forefoot alignment and mobility of the first ray.

J Orthop Sports Phys Ther. 2000;30(10):612-623.

Key Words: first metatarsal, forefoot valgus, forefoot varus

Study Design: Two-group comparison. Objective: To compare scapular kinematics during arm elevation between groups distinguished by pectoralis minor resting length. Background: Studies have demonstrated that individuals with subacromial impingement have altered scapular kinematics, such as loss of posterior tipping and increased internal rotation. One proposed mechanism for these alterations is an adaptively short pectoralis minor. This anterior scapulothoracic muscle may impact normal scapular kinematics if adaptively short. Methods and Measures: Fifty volunteers without shoulder pain were divided into long or short groups according to normalized pectoralis minor resting length. An electromagnetic motion capture system determined the angular orientation of the scapula, humerus, and trunk during arm elevation in 3 separate planes. Groups were compared for 3-dimensional scapular orientation relative to the trunk at arm elevation angles of 30°, 60°, 90°, and 120°, using a mixed-model analysis of variance (ANOVA). Results: There were statistically significant interaction effects between group and arm elevation angle for scapular tipping in all planes of arm elevation, with the scapula for the short group staying anteriorly tipped at higher angles. There was also a significant interaction for scapular internal rotation at lower arm elevation angles in the coronal plane only, with individuals with a shorter pectoralis minor demonstrating a more internally rotated scapula. Conclusions: The group distinguished by a short pectoralis minor demonstrated scapular kinematics similar to the kinematics exhibited in earlier studies by subjects with shoulder impingement. These results support the theory that an adaptively short pectoralis minor may influence scapular kinematics and is therefore a potential mechanism for subacromial impingement.

J Orthop Sports Phys Ther. 2005;35(4):227-238. doi:10.2519/jospt.2005.1669

Key Words: biomechanics, impingement, muscle, shoulder, 3-dimensional

Abnormal scapular kinematics and associated muscle function presumably contribute to shoulder pain and pathology. An understanding of scapular kinematic and electromyographic profiles in asymptomatic individuals can provide a basis for evaluation of pathology. The purpose of this study was to describe normal 3-dimensional scapular orientation and associated muscle activity during humeral elevation. Twenty-five asymptomatic subjects, 19-37 years old, were evaluated. Digitized coordinate data and surface electromyographic signals from the trapezius (upper and lower), levator scapulae, and serratus anterior were collected at static positions of 0°, 90°, and 140° of humeral elevation in the scapular plane. The scapula demonstrated a pattern of progressive upward rotation, decreased internal rotation, and movement from an anteriorly to a posteriorly tipped position as humeral elevation angle increased. Electromyographic activity of all muscles studied increased with increased humeral elevation angles. Differences between mean values at all elevation angles for all variables were significant (p < .05), except for the lower trapezius between the 90° and 140° humeral angles. The results of this study suggest assessment of scapular tipping and internal rotation as well as upward rotation may be necessary to understand pathologies of the shoulder that are related to abnormal scapular kinematics.

J Orthop Sports Phys Ther. 1996;24(2):57-65.

Key Words: scapula, electromyography, shoulder joint

Objectives: To determine whether differences in humeral translations exist between patients with shoulder impingement symptoms and an asymptomatic comparison group, and if so, to determine if shoulder range-of-motion (ROM) measures are associated with abnormal translations.

Background: Abnormal translations of the humeral head are believed to reduce the available subacromial space and to contribute to the development or progression of shoulder impingement symptoms. These abnormal translations have also been theorized to be related to tightness of the posterior capsule and decreased shoulder ROM.

Methods and Measures: Three-dimensional humeral translations were tracked in symptomatic construction workers and an asymptomatic comparison group while elevating the arm in the scapular plane under no-load, 2.3-kg, and 4.6-kg hand-load conditions. Between-group comparisons were made across 3 phases of motion (30°–60°, 60°–90°, and 90°–120°) and the association between humeral translations and cross-body adduction and shoulder internal rotation ROM measures were determined by Pearson correlation analysis.

Results: Persons with shoulder symptoms demonstrated small but significant changes in anterior-posterior translations of the humerus. These changes for the 90°–120° phase of humeral elevation were moderately negatively associated with available cross-body adduction ROM.

Conclusions: The identified kinematic deviations are consistent with possible reductions of the subacromial space. Further study of relationships between posterior capsule tightness, rotator cuff function, and abnormal humeral translations is warranted to better delineate underlying kinematic mechanisms that may contribute to shoulder impingement symptoms and to refine rehabilitation techniques.

J Orthop Sports Phys Ther. 2002; 32(6):248–259.

Key Words: biomechanics, kinematics, shoulder motion abnormalities

Objective:To examine the amount of dorsal first ray mobility in subjects having a history of stress fracture of the second or third metatarsal as compared to control subjects, and to test the influence of navicular drop, length of the first ray, and generalized joint laxity on the measure of dorsal mobility.

Background: Instability of the first ray may cause the lesser metatarsals to carry greater weight and contribute to the incidence of metatarsal stress fracture. Stability of the first ray is believed to be compromised when subtalar joint pronation continues into late stance, the first metatarsal is short, or an individual has generalized joint laxity. To date, no research has assessed the relationship of these etiological factors to the measure of first ray mobility.

Methods and Measures: Fifteen women athletes having a history of a second or third metatarsal stress fracture were matched by age, body mass, and sport activity to women athletes without fracture. Dorsal first ray mobility was quantified by a device using a standard load of 55 N. Change in vertical height of the navicular during stance was the measure of foot pronation. Relative length of the first ray navicular segment compared to the length of the second ray navicular segment was measured by caliper. Generalized joint laxity was evaluated using the Beighton 9-point scale. Within-day repeated measures assessed reliability. Differences between groups were determined by independent t test. Multiple polynomial regression analysis assessed the relationship between dorsal mobility and navicular drop, length of the first ray, and joint laxity.

Results: Interrater reliability coefficients ranged from 0.36 for metatarsal length to 0.71 for navicular drop. The intrarater reliability coefficient for dorsal first ray mobility was 0.93. Dorsal first ray mobility was not significantly different between the 2 groups. With regression analysis, the Beighton score was the only variable retained as a significant predictor of dorsal mobility (R 2=0.24). Conclusion: Results do not support the theory that describes the unstable first ray as a common cause of metatarsal stress fracture. In addition, this investigation found generalized joint laxity to be a significant predictor of dorsal first ray mobility.

J Orthop Phys Ther 2002;32(11):560–567.

Keywords: dorsal mobility, first metatarsal, generalized joint laxity