MRI of impingement syndromes of the shoulder

[Subacromial shoulder impingement]

Impingement, especially subacromial impingement, is one of the most frequent causes of shoulder pain. It results in soft tissue pathologies due to constriction of the subacromial space. It can lead to tendon pathologies and bursitis. In addition to the clinical examination, imaging methods such as magnetic resonance imaging (MRI), MRI arthrography, ultrasound and X‑ray examinations are helpful in making a diagnosis or evaluating the cause of pain. Conservative treatment approaches, such as rest, medication, physiotherapy, manual therapy and infiltrations should primarily be used. If the symptoms do not improve after 3-6 months of conservative treatment, surgical treatment should be considered.

Shoulder impingement: various risk factors for supraspinatus tendon tear: A case group study

A total of 680 cases of monolateral shoulder pain and functional impairment were included, and Chi-Squared tests was incorporated to test for possible associations.No relation between impingement syndrome and potential risk factors was found, such as presence of down slopping (P = .083), presence of ossification acromiale (P  = .102), presence of calcific tendinitis (P  = .144), types of acromion (I [P = .600], II [P = .536], III [P = .633] and IV [P = .832]) and grade of acromioclavicular degenerative changes (mild [P = .077], moderate [P = .111], and severe [P = .700]). However, a significant relationship was uncovered between impingement syndrome and risk factors such as gender (X2 = 7.004, df = 1, P = .08) (where females were more prone), history of shoulder dislocation (X2 = 19.440, df = 1, P = .001), presence of supraspinatus tendon tear or tendinopathy (X2 = 69.344, df = 1, P = .001) and supraspinatus complete tear (X2 = 13.593, df = 1, P = .001). A significant relationship was found between the type of supraspinatus pathology and factors such as gender (female more prone) (X2 = 34.719, df = 3, P = .01), presence of down slopping (X2 = 57.765, df = 3, P = .01), history of shoulder dislocation (X2 = 148.880, df = 3, P = .001), type III of the acromion (X2 = 12.979, df = 3, P = .005), presence of acromioclavicular generative changes mild (X2 = 76.408, df = 3, P = .001) and moderate (X2 = 29.697, df = 3, P = .001), and acromiohumeral distance of ≤3 mm (X2 = 18.915, df = 3, P = .001), 3.1 to 6 mm (X2 = 13.212, df = 3, P = .004), and 9.1-12 mm (X2 = 15.066, df = 3, P = .002). Overall, the Magnetic Resonance Imaging results yielded high sensitivity for detecting full-thickness supraspinatus tears.Considering the findings, this study may help radiologists understand the salient risk factors and identify which factors are mainly responsible for supraspinatus tendon tears and the respective grade of tear (articular partial, bursal partial, complete, or tendinopathy).

The management of shoulder impingement and related disorders: A systematic review on diagnostic accuracy of physical tests and manual therapy efficacy

BACKGROUND

Diagnostic accuracy of physical tests and effectiveness of musculoskeletal rehabilitation of shoulder disorders are still debated.

OBJECTIVES

To investigate diagnostic accuracy of physical tests, efficacy of physiotherapy and coherence between target of assessment and intervention for shoulder impingement and related disorders like bursitis, rotator cuff and long head biceps tendinopathy and labral lesions.

METHODS

A systematic search of four databases was conducted, including RCTs and cross-sectional studies. Cochrane Risk of Bias and QUADAS-2 were adopted for critical appraisal and a narrative synthesis was undertaken.

RESULTS

6 RCTs and 2 cross-sectional studies were appraised. Studies presented low to moderate risk of bias. There is a lack of evidence to support the mechanical construct guiding the choice of physical tests for diagnosis of impingement. Manual techniques appear to yield better results than placebo and ultrasounds, but not better than exercise therapy alone. Discrepancy between the goal of assessment strategies and the relative proposed treatments were present together with high heterogeneity in terms of selection of patients, type of endpoints and follow-ups.

CONCLUSIONS

Musculoskeletal physiotherapy seems to be an effective treatment for patients with shoulder pain although it is still based on weak diagnostic clinical instruments. The adoption of more functional and prognostic assessment strategies is advisable to improve coherence between evaluation and treatment.

Polydeoxyribonucleotide injection in the patients with partial-thickness tear of supraspinatus tendon: a prospective and pilot study using ultrasound

OBJECTIVE

Polydeoxyribonucleotide as adenosine receptor (A_2A) agonist has been used in plastic surgery and dermatology related to its regenerative property. The aim of this pilot study is to evaluate the safety and efficacy of polydeoxynucleotide injection in patients with rotator cuff tears by a variety of outcomes including pain, disability, physical performance test, and ultrasonography (US).

METHODS

Seventeen patients (9 men, 8 women, age: 57.9 ± 9.1) with partial-thickness tear of supraspinatus tendon were evaluated in a prospective, open-label, and pre-and-post study. Seventeen patients underwent 3 times intra-lesional polydeoxynucleotide injection under ultrasound (US) guidance on weeks 0, 2 and 4. The safety and efficacy were assessed on weeks 0, 6 and 12. Main outcome measures included shoulder pain on Visual Analogue Scale (VAS) and DASH (disabilities of arm, hand, shoulder) score, range of motion in shoulder, shoulder strength and tear volume (cm³) by US. Adverse events were monitored. (CRIS: https://www.cris.nih.go.kr , KCT0000767).

RESULTS

Active shoulder pain on VAS reduced from 5.53 to 3.53 (P = 0.016), and acting pain, one of DASH questionnaires, reduced from 3.35 to 2.00 (P < 0.001). However, resting shoulder pain on VAS and total DASH scores were not significantly different. Forward flexion and internal rotation in range of motion improved significantly (from 169.41 to 178.13 degrees [P = 0.004] and from 83.53 to 88.75 degrees [P = 0.014], respectively). The volume of torn lesion decreased during the study period, however it was not significant. There were no significant adverse events leading to hospitalization.

CONCLUSIONS

Minimally invasive procedure through polydeoxynucleotide injection into torn area of supraspinatus tendon on US could be candidate for the safe and effective treatment on shoulder pain and limited range of motion in patients with rotator cuff tear.

Association of Bicipital Peritendinous Effusion with Subacromial Impingement: A Dynamic Ultrasonographic Study of 337 Shoulders

Bicipital peritendinous effusion (BPE) is the most common biceps tendon abnormality and can be related to various shoulder ultrasonographic findings. Since the association of BPE with subacromial impingement is unclear, our study aimed to explore its association with the dynamic subacromial impingement test during ultrasound (US) imaging. We included 337 shoulders referred for US examinations and quantified the amount of BPE. Effusion more than 1 mm in thickness was considered a positive finding. A comparison of three grades of subacromial impingement, adjusted by patient demographics, static sonographic shoulder pathology, and physical findings, by using multivariate regression models revealed that the odds ratio of subacromial impingement (with 95% confidence intervals) in the presence of BPE was 6.54 (3.21-13.32) in grade 1, 6.93 (3.05-15.76) in grade 2 and 3.18 (1.48-6.80) in grade 3. An increase in age, subdeltoid bursitis, full-thickness supraspinatus tendon tear, and shoulder stiffness were also associated with BPE. Since our study demonstrated a positive association of BPE with all grades of impingement, a US dynamic subacromial impingement test is suggested when BPE is present. Future prospective studies are needed to identify changes in BPE after treatment.

Ultrasonographic Evaluation and Feasibility of Posterosuperior Internal Impingement Syndrome: A Case Series

Posterosuperior impingement (PSI) is an underdiagnosed cause of posterior shoulder pain and should be differentiated from classic and external impingement. PSI involves the internal impingement of soft tissues, including the undersurface of the rotator cuff against the posterosuperior labrum when the arm is brought into abduction and external rotation (ABER). Ultrasonography (US) can be useful in the assessment of PSI because of its high resolution and ability to perform during dynamic maneuvers in ABER. This series of 3 cases illustrates the feasibility of US in the evaluation of PSI when the history and physical examination implicate this condition.

LEVEL OF EVIDENCE

V.

Rotator cuff disorders: How to write a surgically relevant magnetic resonance imaging report?

Evaluation of rotator cuff is a common indication for magnetic resonance imaging (MRI) scanning of the shoulder. Conventional MRI is the most commonly used technique, while magnetic resonance (MR) arthrography is reserved for certain cases. Rotator cuff disorders are thought to be caused by a combination of internal and external mechanisms. A well-structured MRI report should comment on the relevant anatomic structures including the acromial type and orientation, the presence of os acromiale, acromio-clavicular degenerative spurs and fluid in the subacromial subdeltoid bursa. In addition, specific injuries of the rotator cuff tendons and the condition of the long head of biceps should be accurately reported. The size and extent of tendon tears, tendon retraction and fatty degeneration or atrophy of the muscles are all essential components of a surgically relevant MRI report.

Clavicular hook plate may induce subacromial shoulder impingement and rotator cuff lesion--dynamic sonographic evaluation

Background

Clavicular hook plates are effective fixation devices for distal clavicle fractures and severe acromioclavicular joint dislocations. However, increasing number of studies has revealed that subacromial portion of the hook may induce acromial bony erosion, shoulder impingement, or even rotator cuff damage. By sonographic evaluation, we thus intended to determine whether the presence of hook plate may induce subacromial shoulder impingement and its relationship relative to surrounding subacromial structures.

Methods

We prospectively followed 40 patients with either distal clavicle fracture or acromioclavicular joint dislocation that had surgery using the Arbeitsgemeinschaft für Osteosynthesefragen (AO) clavicular hook plate. All patients were evaluated by monthly clinical and radiographic examinations. Static and dynamic musculoskeletal sonography examinations were performed at final follow-up before implant removal. Clinical results for pain, shoulder function, and range of motion were evaluated using Constant-Murley and Disability of Arm, Shoulder, and Hand (DASH) scores.

Results

Clinically, 15 out of 40 patients (37.5%) presented with subacromial impingement syndrome and their functional scores were poorer than the non-impinged patients. Among them, six patients were noted to have rotator cuff lesion. Acromial erosion caused by hook pressure developed in 20 patients (50%).

Conclusions

We demonstrated by musculoskeletal sonography that clavicular hook plate caused subacromial shoulder impingement and rotator cuff lesion. The data also suggest an association between hardware-induced impingement and poorer functional scores. To our knowledge, the only solution is removal of the implant after bony consolidation/ligamentous healing has taken place. Thus, we advocate the removal of the implant as soon as bony union and/or ligamentous healing is achieved.

Subcoracoid impingement and subscapularis tendon: is there any truth?

Subcoracoid impingement and stenosis have been described related to anterior shoulder pain and subscapularis tendon tears, but the pathogenesis and related treatment of this condition has still not been explained properly. Variability of coracoid morphology has been described and both traumatic and iatrogenic factors can modify it. Some authors referred this to a primary narrow coracohumeral distance with different threshold values defined as increased risk factor for subscapularis and antero-superior RC tear; opposite theories stated that the stenosis is secondary to an anterosuperior translation of the humeral head toward the coracoid due to degenerative changes of the rotator cuff tendons. Limited coracoplasty can be performed when related risk factors are identified; however no clear consensus arises from specific literature review and extensive clinical and instrumental examination of the patient should be performed in order to identify specific risk factors for subscapularis tendon pathology and, subsequently, tailor the proper approach.

Coracohumeral Distances and Correlation to Arm Rotation: An In Vivo 3-Dimensional Biplane Fluoroscopy Study

Background:

Reduced coracohumeral distances have been reported to be associated with anterior shoulder disorders such as subscapularis tears, biceps tendon injuries, and leading edge supraspinatus tears.

Purpose:

To determine the variability in coracohumeral distance as a function of arm rotation in healthy male subjects. The null hypothesis was that no differences in coracohumeral distance would exist with respect to arm rotation.

Study Design:

Descriptive laboratory study.

Methods:

A total of 9 male participants who had full range of motion, strength, and no prior surgery or symptoms in their tested shoulders were enrolled in this institutional review board–approved study. Computed tomography scans of the shoulder were obtained for each subject. A dynamic biplane fluoroscopy system recorded internal and external shoulder rotation with the arm held in the neutral position. Three-dimensional reconstructions of each motion were generated, and the coracohumeral distance and coracoid index (lateral extension of the coracoid) were measured.

Results:

The mean coracohumeral distance in neutral rotation was 12.7 ± 2.1 mm. A significantly shorter minimum coracohumeral distance of 10.6 ± 1.8 mm was achieved (P = .001) at a mean glenohumeral joint internal rotation angle of 36.6° ± 19.2°. This corresponded to a reduction in coracohumeral distance of 16.4% (range, 6.6%-29.8%). The mean coracoid index was 14.2 ± 6.8 mm. A moderate correlation (R = −0.75) existed between the coracohumeral distance and coracoid index.

Conclusion:

Coracohumeral distance was reduced during internal rotation. Decreased coracohumeral distance was correlated with larger coracoid indices.

Clinical Relevance:

This study provides a reference value for coracohumeral distance in the healthy male population. Knowledge of how coracohumeral distance varies over the range of arm internal-external rotation may improve the clinical diagnosis and treatment plan for patients with anterior shoulder pathology, specifically subcoracoid impingement. Imaging of the coracohumeral distance during internal rotation with the hand at approximately midline should be considered to assess patients with anterior shoulder pain.

Coracoid impingement: current concepts

For many years, coracoid impingement has been a well-recognized cause of anterior shoulder pain. However, a precise diagnosis of coracoid impingement remains difficult in some cases due to the presence of multifactorial pathologies and a paucity of supporting evidence in the literature. This review provides an update on the current anatomical and biomechanical knowledge regarding this pathology, describes the diagnostic process, and discusses the possible treatment options, based on a systematic review of the literature. Level of evidence V.