Subcoracoid impingement syndrome: a painful shoulder condition related to different pathologic factors

The effect of arthroscopic coracoplasty on subscapularis strength in cases of subcoracoid impingement in the absence of subscapularis tear

Subcoracoid impingement leads to anterior shoulder pain, and arthroscopic subcoracoid decompression (coracoplasty) is the preferred treatment in recalcitrant cases. The purpose of the present study was to evaluate the effect of coracoplasty on the severity of anterior shoulder pain and the strength of the subscapularis muscle and to correlate it with the preoperative and postoperative coracohumeral distance (CHD) (t:transverse, s:sagittal). Sixteen patients without any subscapularis tendon tears who underwent arthroscopic subcoracoid decompression and rotator cuff repair with 2 years follow-up were included. Preoperative and postoperative 2-year assessments of function and pain were performed using the modified Kennedy-Hawkins test, power grading of various subscapularis muscle tests, and ASES scores. Preoperative and postoperative coracohumeral distance (tCHD, sCHD) and coracoid overlap (CO) were measured using MRIs before and after surgery. The Mean Hawkins pain score and coracoid overlap were decreased. The strength scores for subscapularis strength testing, ASES score, maximum degree of internal rotation, and coracohumeral distance increased (P < .05). Changes in belly press strength were negatively correlated with postoperative tCHD (r = -0.6, P = .04) and postoperative sCHD (r = -0.7, P = .008). A significant increase in the internal rotation range of the shoulder, subscapularis strength, and relief of anterior shoulder pain was observed. However, this increase was inversely proportional to the postoperative CHD, indicating the mechanical effect of the coracoid on subscapularis strength.

Understanding the Cheerleader as an Orthopaedic Patient: An Evidence-Based Review of the Literature

Cheerleading is a highly popular youth sport in the United States and has been increasingly recognized in recent years for its athleticism and competitive nature. The sport has changed dramatically since its inception. When the sport of cheerleading was first developed, its primary purpose was to entertain crowds and support other athletes. Today, cheerleaders are competitive athletes themselves. Cheerleaders, most of whom are in the pediatric age group, and their parents commonly approach orthopaedic surgeons and sports medicine physicians with questions regarding the risks associated with participation in the sport. Appropriate clinical guidance is especially important for athletes returning to the sport after an injury. However, unlike other popular sports (eg, football, basketball, and volleyball), the intricacies of cheerleading are not well-known to those outside the sport, including many health care providers. Previous studies have reported on the epidemiological patterns of injuries associated with cheerleading and how such aesthetic sports affect the body, finding that fractures and concussions are prevalent and that catastrophic injuries are more common than in most other sports. Here, we provide an evidence-based discussion of 10 pertinent topics regarding cheerleading and its risks to the musculoskeletal system. The purpose of this review is to provide a comprehensive resource for orthopaedic surgeons and sports medicine physicians who care for these athletes.

Acupuncture Treatment for Shoulder Impingement Syndrome: A Review of Randomized Controlled Trials

To evaluate the effectiveness of acupuncture treatment for shoulder impingement syndrome (SIS) a literature review was conducted of randomized controlled trials (RCTs) where acupuncture was used as an intervention for patients diagnosed with SIS. Relevant clinical studies (N = 181) were retrieved from several databases based on the inclusion/exclusion criteria, and the interventions and results were analyzed. Six RCTs were selected to review based on the inclusion and exclusion criteria. In all 6 studies, the acupuncture treatment group showed significant positive changes in indicators evaluating pain, disability, and quality of life. A significant decrease in the evaluation indicators (Shoulder Pain and Disability Index, numeric rating scale, Visual Analogue Scale, Constant Murley Shoulder Assessment Score, patient’s global assessment, and doctor’s global assessment) and a significant increase in the questionnaire scores (UCLA, AL-score, EuroQol 5 Dimension Self-Report Questionnaire, and disabilities of the arm, shoulder, and hand) were observed. In addition, 1 study showed similar improvements in pain and quality of life measures in the acupuncture group and corticosteroid injection group. No major side effects were reported. Acupuncture may be an effective and safe treatment for SIS however, further RCTs are required.

Measurement of the coracohumeral distance on magnetic resonance imaging in a large patient cohort

BACKGROUND

Coracoid impingement syndrome is an increasingly recognized etiology of anterior shoulder pain. Numerus studies have documented the coracohumeral distance (CHD) as a primary or secondary measurement in symptomatic individuals, but there lacks an evaluation of CHD in a large cohort of asymptomatic individuals. The purpose of this study was to quantify a normative distribution of the CHD in a large cohort of healthy, asymptomatic subjects with no history of impingement or shoulder instability.

METHODS

Incoming first-year students in the United States Military Academy were offered enrollment in this study as part of a prospective cohort to assess the normal anatomic relationships of the shoulder girdle. Magnetic resonance images were obtained, and a board-certified, fellowship-trained musculoskeletal radiologist performed measurements of the smallest distance from the coracoid to the humeral head on axial images.

RESULTS

Magnetic resonance images of 714 subjects were available for analysis, including 630 males and 84 females, with a total of 1120 individual shoulders with images of adequate quality. The mean CHD for all shoulders imaged was 13.7 mm. The mean CHD in male shoulders was 13.8 mm, and in female subjects the average was 12.4 mm.

CONCLUSIONS

This study is the largest of its kind to evaluate the CHD in asymptomatic, healthy shoulders to date and demonstrates a mean CHD of 13.7 mm for all subjects. This information can help to standardize "normal" ranges and act as a comparison for future work, when taken in the context of age and imaging in neutral rotation.

Diagnosis and Management of Subcoracoid Impingement

Impingement of the subcoracoid space is a poorly understood pathologic cause of anterior shoulder pain. Because of its relative rarity in isolation and nonspecific presentation, diagnosis and management are often challenging for orthopaedic surgeons and their patients. Stenosis of the subcoracoid space between the lesser tuberosity and the coracoid process <6 mm can lead to anterior shoulder pain and associated rotator cuff and biceps pathology. Multiple imaging modalities are available to assess narrowing of the coracohumeral interval, each with its strengths and limitations. If the patient can be accurately diagnosed with subcoracoid impingement, both conservative and surgical management options are available. Despite earlier case series demonstrating promising results with arthroscopic treatment, comparative studies have yet to support these initial claims.

Radiological Variabilities in Subcoracoid Impingement: Coracoid Morphology, Coracohumeral Distance, Coracoglenoid Angle, and Coracohumeral Angle

BACKGROUND The aim of this study was to investigate the effects of coracoid morphology, coracohumeral distance, coracoglenoid angle, and coracohumeral angle variabilities on subcoracoid impingement development using magnetic resonance imaging (MRI). MATERIAL AND METHODS A total of 200 patients (87 males with mean age of 51.1±15.2 years and 113 females with mean age of 52.6±10.7 years) undergoing shoulder MRI were included in this retrospective study. All MRI studies were performed with standard positioning. Coracoid morphology and subscapularis tendon were evaluated. Coracohumeral distance, coracoglenoid angle and coracohumeral angle were measured in all subjects. One-way ANOVA was used to assess the difference between the groups. For binary comparisons, Tukey post hoc analysis was done. Pearson correlation analysis was performed between variables. RESULTS Type C coracoid was more frequent in the tendinosis and tendon tear groups. There was a significant difference between type C coracoid and the other coracoid types for coracohumeral distance values (P=0.016). There was a statistically significant decrease in coracoglenoid angle values and coracohumeral distance in patients with subscapularis tendon pathologies (P=0.000). A statistically insignificant increase in coracohumeral angle values was found in the subscapularis tendon pathologies. There was a positive correlation between coracohumeral distance and coracoglenoid angle (R=0.749 P=0.000). There was a negative correlation between coracohumeral distance and coracohumeral angle (R=-0.668 P=0.000) and between coracoglenoid angle and coracohumeral angle (R=-0.605 P=0.000). CONCLUSIONS In subscapularis tendon pathologies, decrease in coracohumeral distance and coracoglenoid angle was observed. A new approach uses coracohumeral angle to evaluate subcoracoid impingement. A statistically insignificant increase in coracohumeral angle was noted.

Subacromial impingement syndrome: management challenges

The painful shoulder is the most common condition seen in specialist shoulder clinics. It is often associated with lack of range of motion and reduced shoulder function. Lack of sleep and difficulties in performing basic daily life activities are common findings. Subacromial Impingement Syndrome (SAIS) has been considered as the most common cause of shoulder pain since it was described in 1852. Charles Neer, in 1972, described the presence of a "proliferative spur and ridge" on the undersurface of the acromion, which needs to be removed to improve the symptoms (acromioplasty). Neer's "impingement" hegemony was undisputed for at least 30 years. A more extensive knowledge of the pathogenesis of SAIS, however, has led authors to challenge the role of "impingement" in the shoulder pain and the role of surgical intervention. The aim of this review was to understand if there is still a role for surgical decompression in patients with SAIS. A literature review was performed in PubMed, PEDro, Embase, and the Cochrane Central Register of Controlled Trials using impingement, subacromial space, rotator cuff tears, tendinopathy, and tendinitis as key words. Randomized clinical trials (RCTs) with long-term follow-up comparing surgical intervention and conservative treatments in SAIS were preferred; however, prospective articles studying the outcome of surgical decompression and physiotherapy were also included. The majority of the studies showed no difference in the outcome between patients randomized to surgical decompression or conservative management. However, some studies reported better results after surgery, especially in the long term. Interpretation of the results is very difficult as most of the studies are of poor quality and have short follow-up. In our opinion, the type of subacromial lesion needs to be considered; this may offer an explanation to the difference in severity of symptoms and to the varying degrees of response to certain treatments, including surgery. Further studies are mandatory to better understand the role of surgery in SAIS.

Anatomic Study of Subcoracoid Morphology in 418 Shoulders: Potential Implications for Subcoracoid Impingement

Background:

Subcoracoid impingement has been implicated as a cause of anterior shoulder pain and subscapularis tendon tears.

Purpose/Hypothesis:

The purpose of this study was to evaluate the bony anatomy of the coracoid process and the subcoracoid space. We hypothesized that age-related changes that may contribute to subcoracoid impingement occur in the subcoracoid space.

Study Design:

Descriptive laboratory study.

Methods:

In total, 418 skeletal shoulder specimens were included in this study. We utilized 214 shoulders from a young cohort (25-35 years of age) and 204 shoulders from an older cohort (>55 years of age) for comparison. We evaluated several morphological characteristics of the coracoid process and the subcoracoid space: coracoid width, coracoid shape, coracoid thickness, and subcoracoid distance. Each coracoid was observed for the presence of spurring or other morphological changes.

Results:

The mean anteroposterior (AP) thickness of the coracoid tip was 7.9 and 9.4 mm in our young female and male cohorts, respectively, while the mean AP thickness was 8.1 and 9.7 mm in our older female and male cohorts, respectively. The coracoid tip was hooked in 31 of 108 young female shoulders compared with 55 of 102 older female shoulders, and the coracoid tip was hooked in 25 of 106 young male shoulders compared with 45 of 102 older male shoulders. The mean subcoracoid distance in neutral rotation was 14.8 and 12.5 mm in young and older female shoulders, respectively, while the mean subcoracoid distance in internal rotation in these same cohorts was 8.7 and 7.0 mm, respectively. The mean subcoracoid distance in neutral rotation was 14.8 and 13.3 mm in young and older male shoulders, respectively, while the mean subcoracoid distance in internal rotation was 8.6 and 8.1 mm in young and older male shoulders, respectively.

Conclusion:

The principal findings of our study demonstrate that anatomic changes implicated in subcoracoid impingement may be developmental and worsen with age. The subcoracoid space was narrower in our older cohort of shoulders. Additionally, these older shoulders also had a greater AP width and a more hooked coracoid compared with young shoulders.

Clinical Relevance:

Narrowing of the subcoracoid space has been shown to be implicated as a cause of anterior shoulder pain and subscapularis tendon tears. This is the first study to show that the morphological changes implicated in subcoracoid impingement become more prevalent with age. This may help to explain the increasing prevalence of subscapularis tendon tears in older patients. Furthermore, subcoracoid decompression may be seen as an option for older patients with anterior shoulder pain and subscapularis tendon tears.

Dynamic ultrasonography of the shoulder

Ultrasonography (US) is a useful diagnostic method that can be easily applied to identify the cause of shoulder pain. Its low cost, excellent diagnostic accuracy, and capability for dynamic evaluation are also advantages. To assess all possible causes of shoulder pain, it is better to follow a standardized protocol and to perform a comprehensive evaluation of the shoulder than to conduct a focused examination. Moreover, a proper dynamic study can enhance the diagnostic quality of US, especially when the pathology is not revealed by a static evaluation. The purpose of this article is to review the common indications for dynamic US of the shoulder, and to present the basic techniques and characteristic US findings.

Redefining anterior shoulder impingement: a literature review

Many different types of impingements have been described in the shoulder. Inasmuch as the term 'shoulder impingement' usually refers to subacromial impingement, anterior impingement usually refers to subcoracoid impingement. However, there are many different subtypes of anterior impingements in the shoulder, and awareness of their existence is critical as they vary in their nature and treatment. Recent advances in biomechanical research and arthroscopic exploration of the anterior structures of the shoulder have brought new insights on the various potential impingements, warranting a revision and update of the current definitions of anterior shoulder impingement. The purpose of this article is to propose a comprehensive review and classification of all different subtypes of anterior impingement in the shoulder, including newly described entities.

Sonographic Findings in Subcoracoid Impingement Syndrome: A Case Report and Literature Review

Subcoracoid impingement syndrome is a rare and underrecognized cause of anterior shoulder pain. Currently, subcoracoid impingement syndrome is understood to involve impingement of anatomic structures such as the subcoracoid bursa and subscapularis tendon within the coracohumeral space, and there are no reports of sonographic findings in subcoracoid impingement syndrome other than the impingement of thickened subscapularis bursa. Here we report a case of subcoracoid impingement syndrome, including a novel sonographic finding, arthroscopic findings, and a proposed pathophysiology.

LEVEL OF EVIDENCE

V.

The primer for sports medicine professionals on imaging: the shoulder

Because of its inherent superior soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging (MRI) is highly suited to study the complex anatomy of the shoulder joint, particularly when assessing the relatively high incidence of shoulder injuries in young, athletic patients. This review aims to serve as a primer for understanding shoulder MRI in an algorithmical approach, including MRI protocol and technique, normal anatomy and anatomical variations of the shoulder, pathologic conditions of the rotator cuff tendons and muscles, the long head of the biceps tendon, shoulder impingement, labral and glenohumeral ligament pathology, MR findings in shoulder instability, adhesive capsulitis, and osteoarthritis.

Endothelial dysfunction and tendinopathy: how far have we come?

Symptomatic tendon tears are one of the most important causes of pain and joint dysfunction. Among the intrinsic causes, vascularization recently gained a major role. Endothelial function is indeed a key factor, as well as vascular tone and thrombotic factors, in the regulation of vascular homeostasis and the composition of vascular wall. In this review, we studied systematically whether there is a relationship between endothelial dysfunction and tendinopathy. A literature search was performed using the isolated or combined keywords endothelial dysfunction and tendon,' 'nitric oxide (NO) and tendinopathy,' and 'endothelial dysfunction in tendon healing.' We identified 21 published studies. Of the selected studies, 9 were in vivo studies, 2 focusing on animals and 7 on humans, while 12 reported about in vitro evaluations, where 7 were carried out on humans and 5 on animals. The evidence about a direct relationship between tendinopathy and endothelial dysfunction is still poor. As recent studies have shown, there is no significant improvement in clinical and functional assessments after treatment with NO in patients suffering from tendinopathy in different locations. No significant differences were identified in the outcomes reported for experiment group when compared with controls treated with conventional surgical procedures or rehabilitation programs. Nitric oxide could be a marker to quantify the response of the endothelium to mechanical stress or hypoxia indicating the final balance between vasodilatating and vasoconstricting factors and their effects, but more ad stronger evidence is still needed to fully support this practice.

The painful shoulder: shoulder impingement syndrome

Rotator cuff disorders are considered to be among the most common causes of shoulder pain and disability encountered in both primary and secondary care.

The general pathology of subacromial impingment generally relates to a chronic repetitive process in which the conjoint tendon of the rotator cuff undergoes repetitive compression and micro trauma as it passes under the coracoacromial arch. However acute traumatic injuries may also lead to this condition.

Diagnosis remains a clinical one, however advances in imaging modalities have enabled clinicians to have an increased understanding of the pathological process. Ultrasound scanning appears to be a justifiable and cost effective assessment tool following plain radiographs in the assessment of shoulder impingment, with MRI scans being reserved for more complex cases.

A period of observed conservative management including the use of NSAIDs, physiotherapy with or without the use of subacromial steroid injections is a well-established and accepted practice. However, in young patients or following any traumatic injury to the rotator cuff, surgery should be considered early. If surgery is to be performed this should be done arthroscopically and in the case of complete rotator cuff rupture the tendon should be repaired where possible.

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.

Is arthroscopic coracoplasty necessary in subcoracoid impingement syndrome?

PURPOSE

The purpose of this study was to analyze the outcomes of arthroscopic coracoplasty in the treatment of subcoracoid impingement syndrome.

METHODS

We compared 23 shoulders that underwent arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome with 28 shoulders that did not undergo arthroscopic coracoplasty for the treatment of subcoracoid impingement syndrome, which comprised the control group. All the shoulders had subcoracoid and subacromial impingement syndrome with or without rotator cuff tear. Subcoracoid impingement was defined as a coracohumeral distance of less than 6 mm on the preoperative magnetic resonance image with anterior shoulder pain or tenderness. The 2 groups were further divided into several subgroups according to the size of concomitant rotator cuff tear, and a comparative analysis of functional outcomes after surgery among the subgroups was performed.

RESULTS

In the 2 groups, the overall functional outcomes improved after surgery. The study group showed a significant increase in internal rotation compared with that in the control group (P = .001) at the last follow-up. The large to massive rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .017). On the other hand, no significant difference was seen in the subgroups with small to medium rotator cuff tears including isolated subscapularis tears. The no rotator cuff tear subgroup of the study group showed a significant increase in internal rotation (P = .046).

CONCLUSIONS

Arthroscopic coracoplasty for subcoracoid impingement syndrome can provide a satisfactory outcome. In particular, a significant increase in internal rotation of the treated group was achieved after surgery in comparison with the untreated group, especially in the large to massive rotator cuff tear subgroup and in the no rotator cuff tear subgroup.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

MRI of selected abnormalities at the anterior superior aspect of the shoulder: potential pitfalls and subtle diagnoses

OBJECTIVE

MRI has proven to be a helpful tool in the detection and description of pathologic changes of the rotator cuff, biceps tendon, and glenoid labrum and has thus become a mainstay in the evaluation of patients with shoulder pain. This review seeks to illustrate some of the more subtle abnormalities that can be detected on shoulder MRI and to highlight some normal anatomic variants that may mimic pathologic processes, concentrating on structures at the anterior superior aspect of the shoulder.

CONCLUSION

Shoulder MRI can provide a very accurate evaluation of shoulder pathologic processes and can assist in elucidating abnormalities that can be difficult to diagnose clinically. Awareness of the known anatomic variants and the sometimes subtle potential pain generators at the anterior superior aspect of the shoulder will allow a more accurate interpretation and can therefore increase the diagnostic yield of shoulder MRI.

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.