Background: Patients with a rotator cuff (RC) tear often exhibit scapular dyskinesia with increased scapularlateral rotation and decreased glenohumeral elevation with arm abduction. We hypothesized... Show moreBackground: Patients with a rotator cuff (RC) tear often exhibit scapular dyskinesia with increased scapularlateral rotation and decreased glenohumeral elevation with arm abduction. We hypothesized that inpatients with an RC tear, scapular lateral rotation, and thus glenohumeral elevation, will be restored tonormal after RC repair.Methods: Shoulder kinematics were quantitatively analyzed in 26 patients with an electromagnetic trackingdevice (Flock of Birds) before and 1 year after RC repair in this observational case series.We focusedon humeral range of motion and scapular kinematics during abduction. The asymptomatic contralateralshoulder was used as the control. Changes in scapular kinematics were associated with the gain in rangeof motion. Shoulder kinematics were analyzed using a linear mixed model.Results: Mean arm abduction and forward flexion improved after surgery by 20° (95% confidence interval[CI], 2.7°-36.5°; P = .025) and 13° (95% CI, 1.2°-36.5°; P = .044), respectively. Kinematic analysesshowed decreases in mean scapular protraction (ie, internal rotation) and lateral rotation (ie, upward rotation)during abduction by 3° (95% CI, 0.0°-5.2°; P = .046) and 4° (95% CI, 1.6°-8.4°; P = .042), respectively.Glenohumeral elevation increased by 5° (95% CI, 0.6°-9.7°; P = .028) at 80°. Humeral range of motionincreased when scapular lateral rotation decreased and posterior tilt increased.Conclusions: Scapular kinematics normalize after RC repair toward a symmetrical scapular motion patternas observed in the asymptomatic contralateral shoulder. The observed changes in scapular kinematicsare associated with an increased overall range of motion and suggest restored function of shouldermuscles. Show less
Kolk, A.; Henseler, J.F.; Witte, P.B. de; Arkel, E.R.A. van; Visser, C.P.J.; Nagels, J.; ... ; Groot, J.H. de 2016
BACKGROUND: Subacromial pain syndrome (SAPS) and scapular dyskinesis are closely associated, but the role of pain is unknown. We hypothesized that pain results in asymmetrical scapular kinematics,... Show moreBACKGROUND: Subacromial pain syndrome (SAPS) and scapular dyskinesis are closely associated, but the role of pain is unknown. We hypothesized that pain results in asymmetrical scapular kinematics, and we expected more symmetrical kinematics after infiltration of subacromial anaesthetics. OBJECTIVE: To investigate the effect of subacromial anaesthetics on scapular kinematics in patients with SAPS. DESIGN: Observational cohort study. METHODS: We evaluated shoulder kinematics in 34 patients clinically and radiologically (magnetic resonance arthrography) identified with unilateral SAPS using three-dimensional electromagnetic motion analysis (Flock of Birds). Scapular internal rotation, upward rotation and posterior tilt of the affected shoulder were compared with the kinematics of the unaffected shoulder and following subacromial anaesthetics. Additionally, the association of pain (Visual Analogue Scale, VAS) and scapular rotation was analysed. RESULTS: Compared with the contralateral healthy shoulder, 5° more (95% CI 0.4-9.7, p = 0.034) scapular internal rotation was observed in the affected shoulder at 110-120° of abduction. Following subacromial anaesthetics in the affected shoulder, internal rotation increased (2°, 95% CI 0.5-3.9, p = 0.045) and posterior tilt decreased (3°, 95% CI 1.5-5.0, p = 0.001) at 110-120° of abduction. Less scapular upward rotation was significantly associated with higher pain scores before infiltration (R = 0.45, p = 0.013). CONCLUSIONS: More scapular internal rotation was observed in affected shoulders of patients with SAPS compared with unaffected shoulders. Subacromial infiltration did not restore kinematics toward symmetrical scapular motion. These findings suggest that subacromial anaesthesia is not an effective means to instantly restore symmetry of shoulder motion. Show less
The Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed... Show moreThe Subacromial Impingement Syndrome (SIS) is the most prevalent disorder of the shoulder in primary health care. Acromionplasty, as the main surgical treatment of SIS, is one of the most performed orthopedic surgeries. However, its results are highly variable. Possibly, there are different etiologic subgroups of patients, that might need specific treatment approaches. Several etiologic mechanisms have been described for subacromial narrowing or __impingement__: i.e. 1) structural causes, including acromion shape, subacromial bony spurs, osteophytes; 2) narrowing of the subacromial space due to humerus cranialisation in patients with (micro)instability, or scapular dyskinesia; 3) intrinsic mechanisms such as primary degenerative tendinopathy of the rotator cuff. The aim of this thesis is to unravel the clinical entity __Subacromial Impingement Syndrome__ and to develop methods for identifying distinct etiological patient subgroups that need specific diagnostics and treatment strategies. To this end, we explore the terminological problems and opinions on the main characteristics of SIS amongst international health practitioners, study the prevalence of previously reported etiologic mechanisms in patients with SIS symptoms, develop clinical and biomechanical methods to evaluate and categorize patients with SIS symptoms in diagnostic subgroups, and compare treatment outcomes in trials and follow-up studies. Show less
Witte, P.B. de; Zwaal, P. van der; Arkel, E.R.A. van; Nelissen, R.G.H.H.; Groot, J.H. de 2014
ABSTRACT: BACKGROUND: The Subacromial Impingement Syndrome (SIS) is the most common diagnosed disorder of the shoulder in primary health care, but its aetiology is unclear. Conservative treatment... Show moreABSTRACT: BACKGROUND: The Subacromial Impingement Syndrome (SIS) is the most common diagnosed disorder of the shoulder in primary health care, but its aetiology is unclear. Conservative treatment regimes focus at reduction of subacromial inflammatory reactions or pathologic scapulohumeral motion patterns (intrinsic aetiology). Long-lasting symptoms are often treated with surgery, which is focused at enlarging the subacromial space by resection of the anterior part of the acromion (based on extrinsic aetiology). Despite that acromionplasty is in the top-10 of orthopaedic surgical procedures, there is no consensus on its indications and reported results are variable (successful in 48-90%). We hypothesize that the aetiology of SIS, i.e. an increase in subacromial pressure or decrease of subacromial space, is multi-factorial. SIS can be the consequence of pathologic scapulohumeral motion patterns leading to humerus cranialisation, anatomical variations of the scapula and the humerus (e.g. hooked acromion), a subacromial inflammatory reaction (e.g. due to overuse or micro-trauma), or adjoining pathologies (e.g. osteoarthritis in the acromion-clavicular-joint with subacromial osteophytes). We believe patients should be treated according to their predominant etiological mechanism(s). Therefore, the objective of our study is to identify and discriminate etiological mechanisms occurring in SIS patients, in order to develop tailored diagnostic and therapeutic strategies. METHODS: In this cross-sectional descriptive study, applied clinical and experimental methods to identify intrinsic and extrinsic etiologic mechanisms comprise: MRI-arthrography (eligibility criteria, cuff status, 3D-segmented bony contours); 3D-motion tracking (scapulohumeral rhythm, arm range of motion, dynamic subacromial volume assessment by combining the 3D bony contours and 3D-kinematics); EMG (adductor co-activation) and dynamometry instrumented shoulder radiographs during arm tasks (force and muscle activation controlled acromiohumeral translation assessments); Clinical phenotyping (Constant Score, DASH, WORC, and SF-36 scores). DISCUSSION: By relating anatomic properties, kinematics and muscle dynamics to subacromial volume, we expect to identify one or more predominant pathophysiological mechanisms in every SIS patient. These differences in underlying mechanisms are a reflection of the variations in symptoms, clinical scores and outcomes reported in literature. More insight in these mechanisms is necessary in order to optimize future diagnostic and treatment strategies for patients with SIS symptoms. Trial Registration: Dutch Trial Registry (Nederlands Trial Register) NTR2283. Show less
Huijsmans, P.E.; Witte, P.B. de; Villiers, R.V.P. de; Wolterbeek, D.W.; Warmerdam, P.; Kruger, N.R.; Beer, J.F. de 2011
