Shoulder impingement: relationship of clinical symptoms and imaging criteria

Radiographic findings in patients suspected of subacromial impingement syndrome: prevalence and reliability

OBJECTIVE

Aims were to (i) report prevalence and (ii) evaluate reliability of the radiographic findings in examinations of patients suspected of subacromial impingement syndrome (SIS), performed before a patient's first consultation at orthopaedic department.

MATERIALS AND METHODS

This cross-sectional study examined radiographs from 850 patients, age 18 to 63 years, referred to orthopaedic clinic on suspicion of SIS. Prevalence (%) of radiographic findings were registered. Inter- and intrarater reliability was analysed using expected and observed agreement (%), kappa coefficients, Bland-Altman plots, or intraclass coefficients.

RESULTS

A total of 850 patients with a mean age of 48.2 years (SD = 8.8) were included. Prevalence of the radiographic findings was as follows: calcification 24.4%, Bigliani type III (hooked) acromion 15.8%, lateral/medial acromial spurs 11.1%/6.6%, acromioclavicular osteoarthritis 12.0%, and Bankart/Hill-Sachs lesions 7.1%. Inter- and intrarater Kappa values for most radiographic findings ranged between 0.40 and 0.89; highest values for the presence of calcification (0.85 and 0.89) and acromion type (0.63 and 0.66). The inter- and intrarater intraclass coefficients ranged between 0.41 and 0.83; highest values for acromial tilt (0.79 and 0.83) and calcification area (0.69 and 0.81).

CONCLUSION

Calcification, Bigliani type III (hooked) acromion, and acromioclavicular osteoarthritis were prevalent findings among patients seen in orthopaedic departments on suspicion of SIS. Spurs and Bankart/Hill-Sachs lesions were less common. Optimal reliabilities were found for the presence of calcification, calcification area, and acromial tilt. Calcification qualities, acromion type, lateral spur, and acromioclavicular osteoarthritis showed suboptimal reliabilities. Newer architectural measures (acromion index and lateral acromial angle) performed well with respect to reliability.

Acromiohumeral distance quantification during a variety of shoulder external and internal rotational exercises in recreationally overhead athletes

To determine whether shoulder external (ER) and internal rotational (IR) exercises at five different shoulder abduction angles affect the acromiohumeral distance (AHD). Twenty recreational overhead athletes were included. AHD was measured using real-time ultrasound for each of the five shoulder conditions as follows: neutral shoulder rotation (active-hold) and during ER and IR exercises (isometric and concentric) at five different shoulder-abduction angles (0°, 30°, 45°, 60°, and 90° of abduction). A two-way ANOVA was used to analyze AHD values. Shoulder abduction angle × exercise interaction for AHD was found (F16,304 = 10.92; p < .001; η2 = 0.37). For both isometric and concentric conditions, AHD increased during IR exercises (p < .05) yet decreased during ER exercises (p < .05) when compared with each active-hold positions. Shoulder ER and IR exercises influence the AHD in recreational overhead athletes. A larger AHD was observed during shoulder IR exercises, whereas ER exercises failed to maintain the AHD.

Handball-specific loading acutely reduces the acromiohumeral distance in experienced handball players and in non-handball experienced athletes

Context

When playing handball, the preservation of the subacromial space, which can be quantified by the acromiohumeral distance (AHD), plays a crucial role for shoulder health of handball players. Acute effects of handball-specific loading on the subacromial space with consideration of individual adaptions resulting from long-term handball-specific loading experience have yet to be determined in order to prevent injuries such as e. g. an impingement of the supraspinatus tendon.

Objective

To (1) assess the acute effects of handball-specific loading on the AHD in healthy experienced handball players (HB) and non-handball experienced athletes (CG) and (2) to assess the AHD behavior in relation to individual intrinsic factors to identify possible risk factors and the effect of handball-specific experience associated adaptations.

Participants

20 HB (10m; 10f) and 20 CG (10m; 10f); 24 ± 5 years.

Intervention

Handball-specific loading protocol.

Main outcome measures

The AHD was measured by ultrasonography at 0° and 60° abduction pre and post intervention. Isometric shoulder strength was measured with hand-held dynamometry. Shoulder range of motion (ROM) was measured with goniometry.

Results

Handball-specific loading led to significantly reduced AHD in the dominant shoulder in the 60° abducted position in both groups (HB: −1.7 ± 2.0 mm; p = 0.001, d = 0.69; CG: −1.1 ± 2.0 mm; p = 0.024, d = 0.37) and in the non-dominant shoulder in 0° (−0.7 ± 1.5 mm; p = 0.038, d = 0.35) and 60° abducted position (−1.3 ± 1.8 mm; p = 0.004, d = 0.69) in HB only. Handball-specific loading enhanced AHD reduction when elevating the shoulder from 0° to 60° in both groups and arms. Larger shoulder abduction strength affected the maintenance of the AHD positively. HB demonstrated less shoulder strength compared to CG, while ROM did not differ.

Conclusions

Handball-specific loading can affect the ability to preserve the subacromial space which might put handball players at risk for shoulder injuries. Poor shoulder strength can aggravate this mechanism. Therefore, implementation of strengthening exercises of the external rotator and abductor muscles in the training schedule may improve shoulder health of handball players.

Volumetric evaluation of the subacromial space in shoulder impingement syndrome

INTRODUCTION

Shoulder impingement syndrome is evaluated radiologically with two-dimensional measurement parameters. None of these measurement parameters accurately reflect the three-dimensional geometry. The purpose of this study was to evaluate the volumetric status of the subacromial space in patients with shoulder impingement syndrome and to investigate its relationship with two-dimensional parameters.

HYPOTHESIS

The primary hypothesis of this study is that subacromial volume is reduced in patients with impingement syndrome. The second hypothesis is that the sagittal plane morphology of the acromion reflects the subacromial volume better than the coronal plane morphology.

PATIENTS AND METHODS

This retrospective study consisted of a total of 52 participants: 26 patients with impingement syndrome and 26 controls. Volumetric measurements were performed with using magnetic resonance imaging. The relationship between humerus and acromion was evaluated by acromiohumeral distance. The sagittal plane morphology of the acromion was evaluated with an objective acromial angle, while the coronal plane morphology was evaluated with a lateral acromial angle. The radiological parameters between groups were compared.

RESULTS

The mean subacromial volume was significantly smaller in the impingement group compared to the control group (p=0.01). The subacromial volume had a negative correlation with the objective acromial angle (R=-0.46; p=0.01) The mean tendon volume was significantly higher in the impingement group (p<0.001). The mean acromiohumeral distance in the impingement group (6.8mm±1.0mm), was calculated to be significantly lower than the control group (10.1mm±1.5mm) (p<0.001). There was a positive moderate correlation between subacromial volume and acromiohumeral distance (R=0.61; p=0.01).

DISCUSSION

This is the first study to demonstrate a reduction in subacromial volume in patients with impingement syndrome. The sagittal plane morphology of the acromion, rather than the coronal plane, appears to be more closely related to the subacromial volume.

LEVEL OF EVIDENCE

III; case-control study.

Thoracic manual therapy improves pain and disability in individuals with shoulder impingement syndrome compared to placebo: a randomised controlled trial with one year follow-up

OBJECTIVE

To investigate if muscle energy technique (MET) to the thoracic spine decreases the pain and disability associated with shoulder impingement syndrome (SIS).

DESIGN

Single centre, three-arm, randomised controlled trial, single-blind, placebo control with concealed allocation and a 12-month follow-up.

SETTING

Private osteopathic practice.

INTERVENTIONS

Participants were randomly allocated to: MET to the thoracic spine (MET-only), MET plus soft tissue massage (MET&STM) or placebo.

PARTICIPANTS

3 groups of 25 (n=75) participants ≥ 40 years with SIS received allocated intervention once a week for 15 minutes, 4 consecutive weeks.

OUTCOME MEASURES

Primary outcome measure: Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire.

SECONDARY OUTCOME MEASURES

Shoulder Pain and Disability Index (SPADI) questionnaire, visual analogue scale (VAS-mm/100) -current, 7-day average, 4-week average, patient specific functional scale (PSFS) and global rating of change (GROC). Measures recorded at baseline, discharge, 4-weeks follow-up, 6-months and 12-months. Also baseline and discharge thoracic posture and range of motion (ROM) measured using an inclinometer.

STATISTICAL ANALYSIS

Mixed effects linear regression model for DASH, SPADI, VAS, PSFS, GROC and thoracic posture and ROM.

RESULTS

MET-only group demonstrated significantly greater improvement in pain and disability (DASH, SPADI, VAS 7-day average) compared to placebo at discharge (mean difference DASH=-8.4; 95% CI -14.0,-2.8; SPADI=-14.7;-23.0,-6.3; VAS=-15.5;-24.5,-6.5), 6 -months (-11.1;-18.6,-3.7; -14.9;-26.3,-3.5; -14.1;-26.0,-2.2) and 12 -months (-13.4;-23.9,-2.9; -19.0;-32.4,-5.7; -17.3;-30.9,-3.8). MET&STM group also demonstrated greater improvement in disability, but not pain compared to placebo at discharge (DASH=-8.2;-14.0,-2.3; SPADI= -13.5;-22.3,-4.8) and 6 months (-9.0;-16.9,-1.2; -12.4;-24.3,-0.5). For the PSFS, MET-only improved compared to placebo at discharge (1.3;0.1,2.5) and 12 months (1.8;0.5,3.2); MET&STM at 12 months (1.7;0.3,3.0). GROC: MET-only improved compared to placebo at discharge (1.5;0.9,2.2) and 4 weeks (1.0;0.1,1.9); MET&STM at discharge (1.2;0.5,1.9) and 6 months (1.2;0.1,1.3). There were no differences between MET-only and MET&STM, and no between-group differences in thoracic posture or ROM.

CONCLUSION

MET of the thoracic spine with or without STM improved the pain and disability in individuals over 40 with SIS and may be recommended as a treatment approach for SIS.

[Electrodiagnostic evaluation in differential diagnosis and neurosurgical treatment of radiculopathies caused by spine disorders. Diagnostic value and methodology]

One of the most common causes of radiculopathy requiring neurosurgical treatment is a herniated disc. Magnetic resonance imaging (MRI) is still the main diagnostic approach for this lesion. However, MRI does not allow assessing the functional state of the root. Neurophysiological examination assesses the function of peripheral nervous system. These methods are used for differential diagnosis of causes of neurological symptoms and determine the level of the nerve root injury.

OBJECTIVE

To assess the role of electromyography including paraspinal muscle mapping in diagnosis of radiculopathies following spine diseases.

MATERIAL AND METHODS

We have analyzed literature data in the Scopus, Pubmed, and RSCI databases and selected 93 references for primary reviewing. Final analysis enrolled the manuscripts with a detailed description of neurophysiological examinations and data on sensitivity/specificity of these methods.

RESULTS

Needle electromyography (EMG) is the most informative neurophysiological method for diagnosis of radicular damage. Sensitivity of EMG is up to 90% for lumbosacral radiculopathy. Electromyography of the paraspinal muscles can be used in case of of cervical, thoracic and lumbar radiculopathy in addition to EMG of limb muscles. Therefore sensitivity increases to 100%. Diagnostic value of nerve conduction study (NCS) is low, and performing NCS without EMG is not useful.

CONCLUSION

In neurosurgical practice electrodiagnostic (EDX) should be performed for differential diagnosis of radiculopathy and peripheral nervous system lesions, to determine the level of radicular compression, and when physical examination does not correspond with neuroimaging or MRI is not possible to perform.

Acromiohumeral distance and supraspinatus tendon thickness in people with shoulder impingement syndrome compared to asymptomatic age and gender-matched participants: a case control study

Background

Shoulder impingement syndrome (SIS) is the most common form of shoulder pain. Conservative and surgical treatments for SIS are often not effective. One such surgical intervention is subacromial decompression, aimed at widening the subacromial space (SAS). A better understanding of the changes in the SAS may help explain the relative ineffectiveness of current interventions.

Objective: To measure the acromiohumeral distance (AHD) and supraspinatus tendon thickness (STT) in people with SIS using a case control study.

Methods

The AHD and STT of 39 participants with SIS ≥3 months and 39 age, gender and dominant arm matched controls were measured using ultrasound imaging. Between-group differences for AHD and STT were compared using t-tests. A linear regression was used to determine if there was a relationship between AHD and STT measures, with group as a covariate.

Results

Compared to controls (mean age 55.7 years, SD 10.6), individuals with SIS (mean age 57.1 years, SD 11.1) had a significantly larger AHD (mean difference 2.14 mm, 95% CI 1.21, 3.07, p < 0.001) and STT (mean difference 1.25 mm, 95% CI 0.60, 1.90, p < 0.001). The linear regression model indicated an association between AHD and STT (β = 0.59, 95% CI 0.29, 0.89, p < 0.01, R² = 0.35, n = 78), suggesting that as STT increases in size, so does the AHD.

Conclusion

Individuals with SIS had a larger AHD and greater STT than controls. These results suggest the SAS is already wider in people with SIS and that the symptoms associated with SIS may be more related to an increased STT than a smaller SAS.

Is shoulder geometry important for rotator cuff tears?

PURPOSE

This study is aiming to evaluate some specific anatomic shoulder parameters such as the lateral acromial angle (LAA), acromial index (AI), coracohumeral distance (CHD) and critical shoulder angle (CSA) in rotator cuff tears.

METHODS

A total of 100 cases consisting of 50 patients with rotator cuff tears and 50 patients without rotator cuff tears, who underwent shoulder MRI (mangnetic resonance imaging) examination in Istanbul Medipol University Orthopedics and Traumatology Department, participated in this study. In this retrospective study, CCA, LAA, AI and CSA were evaluated in MRI in order to shed light on the theories of rotator cuff tears.

RESULTS

There was no significant difference (P ˃ .05) in acromial index and coracohumeral distance in the patient group. Lateral acromial angle and critical shoulder angle were significantly different in the patient group compared to the control group (P < .05). There was a weak negative correlation between CSA and CHD.

CONCLUSION

In our study, we found that patients with smaller LAA and higher CSA values in MRI images are prone to have rotator cuff tears. Further studies are needed in order to evaluate whether this association has predictive value.

The critical shoulder angle, the acromial index, the glenoid version angle and the acromial angulation are associated with rotator cuff tears

PURPOSE

To compare the critical shoulder angle (CSA), acromion index (AI), acromion angulation (AA) and glenoid version angle (GVA) between patients with full-thickness rotator cuff tears (RCTs) and patients with intact rotator cuffs.

METHODS

Between 2014 and 2018, the CSA, AI, AA and GVA were measured in consecutively included patients aged > 40 years who underwent shoulder arthroscopy for full-thickness RCTs. A total of 437 patients with RCTs and a mean age of 51.2 years (± 5.8) were included, 35.7% of whom were male. In the control group, there were n = 433 patients (36.3% male) with an intact rotator cuff, and the mean age was 50.7 years (± 5.3).

RESULTS

The mean AI for the RCT group was 0.7 ± 0.1, which was significantly higher than the mean AI for the control group (0.6 ± 0.1, p < 0.001). The mean CSA for the RCT group was 33.6° ± 3.9°, which was significantly higher than the mean CSA for the control group (31.5° ± 4°, p < 0.001). The mean AA for the RCT group was 13.9° ± 9°, which was significantly higher than the mean AA for the control group (12.4 ± 8.6, p = 0.012). The mean GVA for the RCT group was - 3.5° ± 4.6° and significantly retroverted compared with the mean GVA for the control group (- 2.2° ± 4.6°, p < 0.001). The cutoff values determined by the ROC curve analyses were as follows: 0.6 for AI, 31.4° for CSA, 9.6° for AA and - 2.6° for GVA.

CONCLUSION

The CSA, AI, GVA and AA values measured by MRI were determined to be significantly related to full-thickness rotator cuff ruptures. The AI, CSA, AA and GVA may be considered risk factors for degenerative rotator cuff tears. Assessing the CSA, AI, GVA and AA can be helpful for diagnostic evaluation of patients with full-thickness RCTs.

LEVEL OF EVIDENCE

III.

Evaluation of acromial spur using ultrasonography

BACKGROUND

The presence of an acromial spur implies a rotator cuff disorder due to impingement between the acromial spur and the rotator cuff. The purpose of the study was to observe acromial spurs using ultrasonography and to compare measurements between plain radiographs and sonograms.

METHODS

We retrospectively enrolled 51 consecutive patients with acromial spurs, which were interpreted on preoperative plain radiographs (supraspinatus outlet view and 30° caudal tilt) and preoperative sonograms. The ultrasonography transducer was held vertically and continuously moved laterally, which corresponded to the long axis of the long head of the biceps. The distance from the most distal margin of the original acromion to the most projected point of the acromial spur was measured.

RESULTS

No significant difference was found between the plain radiograph and ultrasonography measurements (p=0.186). A moderate to strong correlation was detected between the ultrasonography and supraspinatus outlet-view measurements (r=0.776, p=0.000).

CONCLUSIONS

Anteriorly projected acromial spurs were well-visualized by ultrasonography. No discrepancy in acromial spur length was detected between the use of plain radiography (supraspinatus outlet view and 30° caudal-tilt view) and ultrasonography. The correlation coefficients between the plain radiography and ultrasonography measurements exceeded 0.7.

Feasibility of the acromion index as a reference of severity of stratified supraspinatus tendon injury: a secondary analysis

BACKGROUND

The acromion index (AI) is the acromial lateral extension above the head of the humerus. Some researchers have advocated that the AI indicates the severity of the tear size of the full-thickness supraspinatus tendon.

PURPOSE

To validate the reproducibility of the AI between shoulder magnetic resonance imaging (MRI) and standard X-ray and to verify whether the AI is a useful index for stratifying the severity of supraspinatus tendon injuries, as well as full-thickness tears.

MATERIAL AND METHODS

We enrolled 200 patients with impingement syndrome who were subsequently evaluated with standard X-ray of the shoulder in the anteroposterior view, as well as an MRI. We performed a pilot study to validate the reproducibility of the AI using standard X-ray and MRI, and to compare the AI between these imaging modalities. The severity of supraspinatus tendon injury was classified into four groups (0 = no evidence of injury, 1 = partial tear, 2 = full-thickness tear, and 3 = complete rupture) based on an official reading of the shoulder MRI. We compared the AIs of both modalities between the groups.

RESULTS

Intraclass correlation coefficients of the AIs between the two examiners were 0.819 for MRI and 0.808 for plain X-ray. The mean AI from standard X-ray was greater than that from MRI (P<0.0001). There was no statistical correlation between the AI and the severity of supraspinatus tendon injury.

CONCLUSION

Our findings indicate that the AI cannot be generally used as a predictive reference for the stratified severities of supraspinatus tendon injury.

No relationship between the acromiohumeral distance and pain in adults with subacromial pain syndrome: a systematic review and meta-analysis

To determine whether subacromial space (i.e. acromiohumeral distance; AHD, and/or occupation ratio percentage) differs between people with subacromial pain syndrome (SAPS) and those without. To investigate whether there is a correlation between subacromial space and pain or disability in adults with SAPS and whether temporal changes in pain or disability are accompanied by changes in subacromial space. Systematic review and meta-analysis. Fifteen studies with a total of 775 participants were included. Twelve studies were of high quality and three studies were of moderate quality using the modified Black and Downs checklist. There was no between group difference in AHD in neutral shoulder position (mean difference [95% CI] 0.28 [-0.13 to 0.69] mm), shoulder abduction at 45° (-0.02 [-0.99 to 0.96] mm) or 60° (-0.20 [-0.61 to 0.20] mm). Compared to the control group, a greater occupation ratio in neutral shoulder position was demonstrated in participants with SAPS (5.14 [1.87 to 8.4] %). There was no consistent pattern regarding the correlation between AHD and pain or disability in participants with SAPS, and no consistent increase in subacromial space with improvement in pain or disability over time. The results suggest that surgical (e.g. sub-acromial decompression) and non-surgical (e.g. manual therapy, taping, stretching and strengthening) management of subacromial pain syndrome should not focus solely on addressing a potential decrease in subacromial space, but also on the importance of other biopsychosocial factors.

Prediction of Rotator Cuff Injury Associated with Acromial Morphology: A Three-Dimensional Measurement Study

Objective

To analyze the relationship between the acromial morphology and the related rotator cuff injury using a three‐dimensional (3D) measurement technology.

Methods

For the present study, 226 patients (113 men and 113 women) who underwent shoulder Coarthroscopy from June 2015 to December 2019 at the Department of Orthopedics at our hospital were selected retrospectively. A total of 113 shoulder joints of age‐matched healthy people were selected as the control group. A 3D model coordinate system of the shoulder was established based on CT scan images. Patients were grouped according to the condition of the rotator cuff injury during surgery. The patients whose rotator cuff tear site corresponded to the 3D osseous proliferative structure of the acromion were classified into the impingement injury group (II group). The other patients were classified into the non‐impingement injury group (NII group). The acromiohumeral interval (AHI), the acromial anterior protrusion (AAP), the acromial inferior protrusion (AIP), the acromioclavicular angle (AC angle), the distance from the most medial edge of the acromial anterolateral protrusion (AALP) to the most lateral point of acromion (MLPA) (a), the distance from the most posteromedial edge of the AALP to the MLPA (b), the anteroposterior diameters of the AALP (c), and the proportion of anteroposterior diameters of AALP to the anteroposterior diameters of acromion, (c/c + d) × 100(%), were measured using the 3D shoulder model.

Results

The results of the intraobserver (<5%) and interobserver variability (>87%) analysis found the parameters to have high intraobserver and interobserver concordance. There were no significant differences in age among the control group, the NII group, and the II group (P = 0.8416). There were significant differences in AAP among the three groups (P = 0.0374). The results were the same for men and women, respectively. The AAP in the control group and the NII group did not show a difference, while the AAP in the II group was increased by 26.9% (P = 0.015) and 25% (P = 0.023), respectively, compared with the NII group and the control group. AHI, AIP, and AC angles did not show significant differences among the three groups (P > 0.05). The (a) and (b) of the II group were significantly larger than those of the NII group; P‐values were 0.0119 and 0.0003, respectively. The (a) and (b) in patients with rotator cuff injuries were larger than in the normal population (P < 0.05). The above results were the same for men and women. This suggested that the larger width of the AALP might cause the related rotator cuff injury. The (c/c + d) in the II group was significantly larger than those in the control and the NII groups, with P‐values of 0.0005 and 0.0021, respectively. The risk of rotator cuff injury due to subacromial impingement was increased when the maximum width of the medial–lateral edge of the AALP exceeded 16.8 mm (17.4 mm in men, 15.1 mm in women), the maximum width of the posterior edge of the AALP exceeded 12.9 mm (13.8 mm in men,12.7 mm in women), or the anteroposterior diameters of the AALP exceeded the anteroposterior diameters of the acromion by 33.5%.

Conclusion

We could predict the occurrence and development of the related rotator cuff injury in symptomatic patients with specific 3D changes in their acromion and intervene in the acromion of such patients as early as possible to prevent possible rotator cuff injuries in the future.

Relationship Between Shoulder Impingement Syndrome and Thoracic Posture

BACKGROUND

Shoulder impingement syndrome (SIS) is the most common form of shoulder pain and a persistent musculoskeletal problem. Conservative and invasive treatments, aimed at the shoulder joint, have had limited success. Research suggests shoulder function is related to thoracic posture, but it is unknown whether thoracic posture is associated with SIS.

OBJECTIVE

The objective of this study was to investigate whether there is a relationship between SIS and thoracic posture.

DESIGN

This was a case control study.

METHODS

Thoracic posture of 39 participants with SIS and 39 age-, gender-, and dominant arm-matched controls was measured using the modified Cobb angle from a standing lateral radiograph. Thoracic range of motion (ROM) was also measured using an inclinometer. Between-group differences were compared using t tests. The relationship between thoracic posture and thoracic ROM was determined with linear regression.

RESULTS

Twenty women and 19 men with SIS (mean age = 57.1 years, SD = 11.1) and 39 age-matched, gender-matched, and dominant arm-matched controls (mean age = 55.7years, SD = 10.6) participated. Individuals with SIS had greater thoracic kyphosis (mean difference = 6.2o, 95% CI 2.0-10.4) and less active thoracic extension (7.8o, 95% CI = 2.2-13.4). Greater thoracic kyphosis was associated with less extension ROM (ie, more flexion when attempting full extension: β = 0.71, 95% CI = 0.45-0.97).

LIMITATIONS

These cross-sectional data can only demonstrate association and not causation. Both radiographic measurements and inclinometer measurements were not blinded.

CONCLUSION

Individuals with SIS had a greater thoracic kyphosis and less extension ROM than age- and gender-matched healthy controls. These results suggest that clinicians could consider addressing the thoracic spine in patients with SIS.

Intra- and Inter-Rater Reliability of Ultrasound Measurements of Supraspinatus Tendon Thickness, Acromiohumeral Distance, and Occupation Ratio in Patients With Shoulder Impingement Syndrome

Objectives

This study aims to evaluate the intra- and inter-rater reliability coefficients of the supraspinatus tendon thickness, acromiohumeral distance, and occupation ratio in patients with shoulder impingement syndrome.

Patients and methods

The study included 83 patients (21 males, 62 females; mean age 51.6±11.0 years; range, 26 to 70 years) with shoulder impingement syndrome. The supraspinatus tendon thickness, acromiohumeral distance, and occupation ratio values were obtained one week apart by two observers. The intraclass correlation coefficient (ICC), minimum detectable change, and standard error of measurement were calculated.

Results

The first observer had excellent intra-rater reliability in all measurements (ICC >0.90) with minimum detectable change of 0.740-0.047 mm and standard error of measurement of 0.017-0.26 mm. The second observer had excellent intra-rater reliability in supraspinatus tendon thickness and acromiohumeral distance measurements (ICC >0.90) with minimum detectable change of 0.498-0.770 mm and standard error of measurement of 0.18-0.28 mm and good intra-rater reliability in the occupation ratio measurement (ICC; 0.75-0.90) with minimum detectable change of 0.060 mm and standard error of measurement of 0.022 mm. Inter-rater reliability coefficients were 0.916 (95% confidence interval [CI]; 0.873-0.945) for supraspinatus tendon thickness, 0.943 (95% CI; 0.914-0.963) for acromiohumeral distance with minimum detectable change of 0.673 mm and standard error of measurement of 0.243 mm and 0.790 (%95 CI; 0.693-0.853) for occupation ratio with minimum detectable change of 0.077 mm and standard error of measurement of 0.028 mm.

Conclusion

These findings suggest that ultrasonographic measurements of the supraspinatus tendon thickness, acromiohumeral distance and occupation ratio can be reliable and consistent for clinical evaluation of patients with shoulder impingement syndrome in terms of supporting diagnosis and monitoring the treatment effect.

Evaluation of the cross-sectional area of acromion process for shoulder impingement syndrome

Background

Anatomic changes in the acromion have been considered a main cause of shoulder impingement syndrome (SIS). To evaluate the relationship between SIS and the acromion process, we devised a new morphological parameter called the acromion process cross-sectional area (APA). We hypothesized that the APA could be an important morphologic diagnostic parameter in SIS.

Methods

We collected APA data from 95 patients with SIS and 126 control subjects who underwent shoulder magnetic resonance imaging (MRI). Then we measured the maximal cross-sectional area of the bone margin of the acromion process on MRI scans.

Results

The mean of APAs were 136.50 ± 21.75 mm² in the male control group and 202.91 ± 31.78 mm² in the male SIS group; SIS patients had significantly greater APAs (P < 0.001). The average of APAs were 105.38 ± 19.07 mm² in the female control group and 147.62 ± 22.90 mm² in the female SIS group, and the SIS patients had significantly greater APAs (P < 0.001). The optimal APA cut-off in the male group was 165.14 mm² with 90.2% sensitivity, 91.4% specificity, and an area under the curve (AUC) of 0.968. In the female group, the optimal cut-off was 122.50 mm² with 85.2% sensitivity, 84.9% specificity, and an AUC of 0.928.

Conclusions

The newly devised APA is a sensitive parameter for assessing SIS; greater APA is associated with a higher possibility of SIS. We think that this result will be helpful for the diagnosis of SIS.

Does the critical shoulder angle decrease after anterior acromioplasty?

INTRODUCTION

No clinical studies to date have analyzed the critical shoulder angle (CSA) following anterior acromioplasty. Our study's main objective was to measure the change in the CSA after acromioplasty.

MATERIALS AND METHODS

Ninety patients were included in this retrospective series. The CSA and the type of acromion were evaluated before and after surgery.

RESULTS

The average CSA for patients before surgery was 35.9° (± 3.7, 26.2, 44.2) and 33° after the acromioplasty (± 3.5, 24.8, 41.4). The decrease was significant and 2.9° on average (± 2.2, - 2.2, 11.9, p = 0.000). Preoperatively, 58% of patients had a CSA ≥ 35° (n = 52) and 24% postoperatively (n = 22, p = 0.000).

CONCLUSIONS

Standardized anterior acromioplasty allows for a significant decrease in the CSA without lateral resection of the acromion. This study confirms the tight link between the CSA and the anterior acromion as well as the interest of this angle to quantify acromioplasty whether anterior or lateral.

LEVEL OF EVIDENCE

Level IV, Case Series, Retrospective design.

Subacromial space volume in patients with rotator cuff tear: The effect of surgical repair

Objective

The aim of this study was to evaluate the effect of the rotator cuff tear repair on subacromial space volume.

Methods

We retrospectively identified 21 eligible patients (5 males and 16 females; mean age: 56.4 (range; 46–71) years) who had shoulder arthroscopy for unilateral full-thickness small to medium rotator cuff tear and normal controlateral shoulder joint. The mean follow-up time was 16.1 (range; 12–25) months. Preoperative and postoperative 1 year bilateral shoulder MRIs and Constant scores were reviewed. Subacromial volume was calculated by using Osirix software. Pre-, postoperative and healthy side (contralateral control group) subacromial volumes were recorded. Paired sample and t-tests were used to compare the pre- and postoperative groups. Independent sample t-tests were used to compare the healthy and pre- and postoperative groups. The correlation between the changes in the subacromial volume and the shoulder Constant score were analyzed using Pearson correlation analyses.

Results

The mean subacromial volume of the preoperative group was 2.95 cm³ (range; 1.53–4.23) and the postoperative group was 3.59 cm³ (range; 2.12–4.84). The volume increase was statistically significant (p < 0.05). The mean subacromial volume of the control group was 3.93 cm³ (range; 2.77–5.03), and the difference between the preoperative group and the control group was statistically significant. There was no significant difference found between the postoperative group and the control group (p = 0.156). There was no significant correlation found between the volume and the constant score changes (r = 0.170, p = 0.515).

Conclusion

The subacromial space volume significantly decreases in full-thickness rotator cuff tears smaller than 3 cm and the surgical repair increases the subacromial volume significantly.

Level of evidence

Level IV; Diagnostic Study.

Active Scapular Retraction and Acromiohumeral Distance at Various Degrees of Shoulder Abduction

CONTEXT

  Performing shoulder-abduction exercises with scapular retraction has been theorized to reduce the potential for shoulder impingement. However, objective data to support this premise are lacking.

OBJECTIVE

  To evaluate the influence of active scapular retraction on acromiohumeral distance (AHD) at 4 shoulder-abduction angles using real-time ultrasound.

DESIGN

  Cross-sectional study.

SETTING

  University laboratory.

PATIENTS OR OTHER PARTICIPANTS

  Twenty asymptomatic individuals (10 men, 10 women; age = 22.9 ± 2.8 years, height = 169.3 ± 9.5 cm, mass = 65.5 ± 12.9 kg) were recruited.

MAIN OUTCOME MEASURE(S)

  Real-time ultrasound images of AHD were obtained during nonretracted and retracted scapular conditions at 0°, 45°, 60°, and 90° of shoulder abduction. A 2-factor analysis of variance with repeated measures was used to evaluate the influence of shoulder retraction on AHD across shoulder-abduction angles.

RESULTS

  A scapular-retraction condition × shoulder-abduction-angle interaction for AHD was found ( F_3,57 = 4.56, P = .006). The AHD was smaller at 0° (10.5 versus 11.2 mm, respectively; t₁₉ = 2.22, P = .04) but larger at 90° (9.4 versus 8.7 mm, respectively; t₁₉ = -2.30, P = .04) of shoulder abduction during the retracted than the nonretracted condition. No differences in AHD were observed between conditions at 45° ( t₁₉ = 1.45, P = .16) and 60° ( t₁₉ = 1.17, P = .86) of abduction.

CONCLUSIONS

  The observed differences in AHD at 0° and 90° of shoulder abduction were small and did not exceed the established minimal detectable change for either angle. Our findings suggest that active scapular retraction during shoulder abduction has a minimal influence on AHD at 0° and 90° in healthy individuals. Further investigations are needed to determine whether scapular retraction influences AHD in individuals with subacromial impingement.

What Imaging-Detected Pathologies Are Associated With Shoulder Symptoms and Their Persistence? A Systematic Literature Review

Objective

Shoulder symptoms are common, and imaging is being increasingly used to help with management. However, the relationship between imaging and symptoms remains unclear. This review aims to understand the relationship between imaging‐detected pathologies, symptoms, and their persistence.

Methods

A systematic review using Medline, EMBASE, Cochrane, and grey literature was conducted to April 2017. The cross‐sectional and longitudinal relationships between imaging‐detected abnormalities and symptoms were analyzed and associations qualitatively characterized by a best‐evidence synthesis based on study design, covariate adjustment, and the Grade of Recommendations Assessment, Development, and Evaluation (GRADE) methodology. Modalities included ultrasound, magnetic resonance imaging (MRI), radiographs, positron emission tomography (PET), bone scintigraphy, and computed tomography.

Results

A total of 6,569 abstracts was screened and 56 articles were included. In total, 50 studies did not adjust for covariates and 36 analyzed individual pathologies only. The majority of studies showed conflicting results. There was no significant association between most imaging features and symptoms among high‐quality, cross‐sectional studies. There was low‐quality evidence that enhancement of the joint capsule on MRI and increased uptake on PET were associated with symptoms in adhesive capsulitis. Based on high‐quality longitudinal studies, enlarging rotator cuff tears were associated with an increased incidence of symptoms.

Conclusion

There were conflicting results on the association of imaging features with shoulder symptoms and their persistence. The existing evidence was very low in quality, based on the GRADE methodology. Further high‐quality studies are required to understand the relationship between imaging and shoulder symptoms and to determine the appropriate role of imaging in care pathways.

Morphological classification of acromial spur: correlation between Rockwood tilt view and arthroscopic finding

Purpose and hypothesis: Acromion spur is the extrinsic factor for impingement syndrome and rotator cuff tear. The Rockwood tilt view can be used to evaluate prominence of the anterior acromion, however no study has shown the correlation of findings between the Rockwood tilt view and the arthroscopic finding.

METHODS

We developed the arthroscopic classification of acromion spur as type 1 flat spur, type 2 bump spur, type 3 heel spur, type 4 keel spur, and type 5 irregular spur. Patients with rotator cuff syndrome who underwent arthroscopic surgery were recruited. Two observers were asked to classify the type of spur from arthroscopic findings and Rockwood tilt views separately in random pattern. The prevalence of supraspinatus tendon tear was also recorded as no tear, partial-thickness tear, and full-thickness tear.

RESULTS

The keel spur (33.9%) was the most common finding followed by the heel spur (27.8%). The correlation was high especially for the heel, the keel, and the irregular spur (75.47%, 74.03%, and 72.73%, respectively.) These three types of spurs have a high prevalence of full thickness of supraspinatus tendon tear.

CONCLUSION

The Rockwood tilt view can be used to evaluate the morphology of an acromion spur, especially the at-risk spur that correlates highly with the full-thickness supraspinatus tendon tear. The arthroscopic classification will also be a useful tool to improve communication between the surgeon and the guide for appropriate treatment in a rotator cuff tear patient when encountering the heel, keel, and irregular spur.

Shoulder impingement syndrome: a systematic review of clinical trial participant selection criteria

BACKGROUND

Shoulder impingement syndrome (SIS) is a common diagnosis for patients with pain and dysfunction of the shoulder. Variations in the signs and symptoms might lead to uncertainty regarding the definition of SIS. The aim of this review is to explore the participant selection criteria used in the literature when investigating SIS and to assess differences in criteria among treating professions.

METHODS

This is a PRISMA systematic review of publications from 2009 to 2014 from MEDLINE, PubMed, The Cochrane Library, Embase, Scopus and CINAHL.

RESULTS

Ninety-seven articles met inclusion criteria for this review. Twenty-five different surgical and nonsurgical treatments were investigated. Impingement-specific index tests were used in all studies. Exclusion index tests were used in 62% of studies. Twenty index tests were identified. Radiological investigations were reported in 53% of all studies, of which a further 53% reported using two or more radiological investigations.

CONCLUSIONS

This systematic review has illustrated that studies investigating SIS test for various signs and symptoms, which is in keeping with describing the condition as a 'syndrome'. However, there are inconsistencies in participant selection criteria between health disciplines, highlighting a need for harmonization of the selection criteria in the form of an international editorial consensus.

Shoulder-Rotator Strength, Range of Motion, and Acromiohumeral Distance in Asymptomatic Adolescent Volleyball Attackers

CONTEXT

Sport-specific adaptations at the glenohumeral joint could occur in adolescent athletes because they start participating in high-performance sports in early childhood.

OBJECTIVE

To investigate shoulder-rotator strength, internal-rotation (IR) and external-rotation (ER) range of motion (ROM), and acromiohumeral distance (AHD) in asymptomatic adolescent volleyball attackers to determine if they have risk factors for injury.

DESIGN

Cross-sectional study.

SETTING

University laboratory.

PARTICIPANTS

Thirty-nine adolescent high school-aged volleyball attackers (22 boys, 17 girls; age = 16.0 ± 1.4 years, height = 179.2 ± 9.0 cm, mass = 67.1 ± 10.9 kg, body mass index = 20.7 ± 2.6 kg/m²).

MAIN OUTCOME MEASURE(S)

Shoulder IR and ER ROM, total-rotation ROM, glenohumeral IR deficit, AHD, and concentric and eccentric strength of the shoulder internal and external rotators were tested bilaterally.

RESULTS

External-rotation ROM was greater (t₃₈ = 4.92, P < .001), but IR ROM (t₃₈ = -8.61, P < .001) and total ROM (t₃₈ = -3.55, P = .01) were less in the dominant shoulder, and 15 athletes had a glenohumeral IR deficit (IR ROM loss > 18°). We observed greater concentric internal-rotator (t₃₈ = 2.89, P = .006) and eccentric external-rotator (t₃₈ = 2.65, P = .01) strength in the dominant than in the nondominant shoulder. The AHD was less in the dominant shoulder (t₃₈ = -3.60, P < .001).

CONCLUSIONS

Adolescent volleyball attackers demonstrated decreased IR ROM, total ROM, and AHD and increased ER ROM in their dominant shoulder. Therefore, routine screening of adolescent athletes and designing training programs for hazardous adaptive changes could be important in preventing shoulder injuries.

Differences in acromial morphology of shoulders in patients with degenerative and traumatic supraspinatus tendon tears

PURPOSE

Distinct characteristics of acromial morphology seem to be one factor for the development of degenerative supraspinatus tendon tears. Thus, it is questionable whether patients with traumatic tendon tears also present these parameters. The hypothesis of the present study was that the acromial morphology of patients with degenerative supraspinatus tendon tears differs from patients with traumatic tears.

METHODS

One hundred and thirty-six patients that were treated by arthroscopic rotator cuff repair from 2010 to 2013 were included in this study. Seventy-two patients had degenerative (group 1), and 64 had traumatic (group 2) supraspinatus tendon tears. On preoperative radiographs the Bigliani type, acromial slope, acromiohumeral (AH) distance, lateral acromial angle (LAA), acromion index (AI), and critical shoulder angle (CSA) were measured. Medians of these parameters as well as of age of both groups were compared using the t test.

RESULTS

The percentaged distribution of the Bigliani type differed (group 1 vs. 2: type 1: 18/38, type 2: 56/55, type 3: 26/8). All parameters showed significant differences between degenerative and traumatic tears. Slope: 21.2° (SD 7.6°) versus 19.2° (SD 7.9°, p = 0.026), AH distance: 8.4 mm (SD 2.3 mm) versus 9.9 mm (SD 1.9 mm, p = 0.0006), LAA: 77.0° (SD 4.0°) versus 82.5° (SD 4.7°, p < 0.0001), AI: 0.77 (SD 0.07) versus 0.73 (0.06, p = 0.0239), and CSA: 36.8° (SD 3.6°) versus 35.3° (SD 2.9°, p = 0.007). An LAA <70° or an AH distance of <5 mm only occurred in degenerative tears. Patients with degenerative tears were significantly older (60 vs. 54 years).

CONCLUSIONS

The hypothesis that the acromial morphology of patients with degenerative supraspinatus tendon tears differs from patients with traumatic tears was confirmed. Shoulders with degenerative tears show a narrower subacromial space and a larger lateral extension as well as a steeper angulation of the acromion than with traumatic tears. Thus, the results of this study support the theory of external impingement as a cause for degenerative rotator cuff tears.

LEVEL OF EVIDENCE

IV.

Subacromial Space Width: Does Overuse or Genetics Play a Greater Role in Determining It? An MRI Study on Elderly Twins

BACKGROUND

Age and peripheral microcirculation disorders are the main causes of rotator cuff degeneration. Acromion variants may affect subacromial space width, causing a pathological narrowing of the space that may compromise the cuff integrity. However, it is not clear if the subacromial space width is genetically determined or if it changes according to loading conditions. To clarify this unresolved question, we performed an MRI (magnetic resonance imaging) study with the aim of evaluating the acromiohumeral distance in a group of elderly monozygotic and dizygotic twins, and we analyzed the obtained data using the twin design to separate the contributions of shared and unique environments.

METHODS

We identified twenty-nine pairs of elderly twins. On MRI scans, we evaluated the acromiohumeral distance and health status of the rotator cuff tendons. Heritability, defined as the proportion of total variance of a specific characteristic in a particular population due to a genetic cause, was estimated as twice the difference between the intraclass correlation coefficients for monozygotic and dizygotic pairs. The influence of shared environment, due to environmental factors that contribute to twin and sibling similarity, was calculated as the difference between the monozygotic correlation coefficient and the heritability index. One-way ANOVA (analysis of variance) was used to estimate the differences among job categories, both in the total cohort and within zygosity groups.

RESULTS

The intraclass correlation coefficient was substantially higher for monozygotic than for dizygotic twins, indicating a high degree of concordance of the acromiohumeral distance in pairs of individuals who shared 100% of their genes. The heritability index was 0.82, and shared and unique environmental contributions were both 0.09. There were no significant differences among subjects in different job categories, either in the total cohort (p = 0.685) or within the monozygotic (p = 0.719) and dizygotic groups (p = 0.957).

CONCLUSIONS

The acromiohumeral distance is mainly genetically determined and only marginally influenced by external factors.

Medium-term natural history of subacromial impingement syndrome

BACKGROUND

We evaluated the factors that affect the natural course of subacromial impingement syndrome in patients without rotator cuff tears.

METHODS

In total, 63 patients were included. During the first evaluation, we recorded each patient's age, gender, profession, body mass index (BMI), hand dominance, alcohol and tobacco consumption, comorbidities, causative event of pain, presence of a functional limitation, duration of symptoms, shoulder scores (American Shoulder and Elbow Surgeons [ASES], Constant-Murley, and visual analog scale), history of subacromial steroid injections, and magnetic resonance imaging (MRI) classification. A subacromial lidocaine injection test was performed to confirm the diagnosis, and patients were initially treated conservatively. Of the 63 patients, 7 underwent a subsequent surgical procedure. We recalled the patients and questioned them about recurrences. According to their answers, the patients were grouped as follows: group 1, no recurrence; group 2, relapsing course; and group 3, chronic course. We compared the groups regarding the factors proposed to affect the course of the disease.

RESULTS

The mean follow-up time was 8.45 ± 0.9 years. There were no significant differences regarding gender, profession, hand dominance, alcohol consumption, smoking, comorbidities, causative event of pain, visual analog scale score, or history of subacromial steroid injections between groups. The patients in group 1 were significantly younger than those in group 2 (P = .038). The mean BMI value of the group 1 patients was significantly lower than that of the group 3 patients (P = .034). Patients with a functional limitation besides pain tended to have a relapsing course. The Constant-Murley and ASES scores were significantly higher for patients in group 1 than for patients in group 2 (P = .024 and P = .041, respectively). The duration of symptoms was significantly shorter (<3 months) in group 1 (P = .001). Most of the patients in group 1 had reversible changes on MRI (P = .038).

CONCLUSION

In our study, younger age, lower BMI, more functional capacity, a shorter symptomatic period, reversible changes on MRI, and higher Constant and ASES scores at the first evaluation were good prognostic factors.

Effects of a synovial fluid substitute on early recovery after arthroscopic subacromial decompression of the shoulder

PURPOSE

The purpose of this pilot study was to determine whether the use of a synovial fluid substitute (Viscoseal) after arthroscopic subacromial decompression (ASD) of the shoulder was safe (primary outcome) and effective in reducing the postsurgical pain on the day of surgery and the time from surgery to discharge (secondary outcomes), compared with patients undergoing standard ASD alone.

METHODS

Forty-six patients with primary isolated shoulder subacromial impingement were randomly assigned to either undergo SAD alone (control group: n = 21) or to receive 10 ml Viscoseal into the subacromial space at the end of the procedure (treatment group: n = 25).

RESULTS

No adverse events were reported in either group. All clinical scores improved significantly in each group from preoperative to 12-week follow-up (p < 0.01). The Viscoseal group experienced significantly (p = 0.001) less severe pain 4 h after the surgery {mean 54.0 ± 43.1, median 50 [interquartile range (IQR) 0-100]} and shorter time from surgery to discharge [mean 5.2 ± 1.4, median 5 (IQR 4-6)] than the control group [mean 102.4 ± 40.2, median 100 (IQR 50-150) and mean 11.0 ± 5.3, median 12 (IQR 6-16), respectively]. The Viscoseal group also required less analgesia postoperatively than the control group in the first 8 h: 24% of the Viscoseal required no analgesia, while all patients in the control group required analgesia; 24% of the control group required opiates compared with 4% in the Viscoseal group.

CONCLUSION

Viscoseal was safe and well tolerated after shoulder arthroscopy. It provided excellent pain relief and a faster discharge time after ASD of the shoulder. The use of Viscoseal should be investigated in larger randomized controlled trials and for other shoulder arthroscopy procedures.

LEVEL OF EVIDENCE

Level II, Pilot Prospective Comparative Study.

Comparative analysis of acromiohumeral distances according to the locations of the arms and humeral rotation

[Purpose] The purpose of this study was to compare the potential effects of resistance exercise according to the positions of the arms and the rotation of the humerus on the subhumeral acromial space. [Subjects] The study subjects were 34 subjects without shoulder pain. [Methods] Ultrasonographic measurements of the acromiohumeral distance of the subjects were made at three shoulder positions: 90° flexion, scaption at 90° abduction, and 90° abduction in an upright sitting position. The subjects were instructed to vertically push against a table to the maximum level with the humerus in internal, neutral, and external rotation. The measurements were made three times in each position. [Results] There was a significant difference in acromiohuneral distance between neutral and internal rotation of the humerus, and between external rotation and internal rotation of the humerus. In the scaption position, there was a significant difference between neutral and internal rotation of the humerus, and between external rotation and internal rotation of the humerus. In the 90° flexion position, there was a significant difference between neutral and internal rotation, and between neutral and external rotation. There was a significant difference between the flexion position and the abduction position, and between the flexion position and the scaption position. In terms of the internal rotation of the humerus, there was a significant difference between 90° flexion and 90° abduction. [Conclusion] These findings can be applied in exercises prescribed to increase the acromiohumeral distance and to aid the treatment and evaluation of shoulder dysfunctions.

Cranial humerus translation, deltoid activation, adductor co-activation and rotator cuff disease - different patterns in rotator cuff tears, subacromial impingement and controls

BACKGROUND

Arm adductor co-activation during abduction has been reported as a potential compensation mechanism for a narrow subacromial space in patients with rotator cuff dysfunction. We assessed differences in acromiohumeral distance at rest and the amount of humerus translation during active abduction and adduction in patients with rotator cuff tears (n=20) and impingement (n=30) and controls (n=10), controlled for deltoid, pectoralis major, latissimus dorsi and teres major activation (electromyography).

METHODS

During the acquirement of shoulder radiographs, subjects performed standardized isometric arm abduction and adduction tasks. EMG's were normalized between -1 and 1 using the "Activation Ratio", where low values express (pathologic) co-activation, e.g. adductor activation during abduction.

FINDINGS

In patients with cuff tears mean rest acromiohumeral distance was 7.6mm (SD=1.6): 3.5mm narrower compared to patients with impingement (95%-CI: 2.4-4.5) and 1.3mm narrower compared to controls (95%-CI: -0.1-2.7). Both during abduction and adduction tasks, cranial translation was observed with equal magnitudes for patients and controls, with average values of 2.3 and 1.7mm, respectively. Where patients with cuff tears had lower adductor Activation Ratios (i.e. more adductor co-activation during abduction), no association between abductor/adductor muscle activation and acromiohumeral distance was found.

INTERPRETATION

The subacromial space is narrower in patients with rotator cuff tears compared to patients with impingement and controls. We found additional subacromial narrowing during isometric abduction and, to a lesser amount, during adduction in all subjects and more adductor co-activation in patients with cuff tears. We found no association between subacromial space and activation of the deltoid and main adductors.

Imaging-guided subacromial therapeutic injections: prospective study comparing abnormalities on conventional radiography with patient outcomes

OBJECTIVE

The purpose of this study was to compare abnormalities detected on conventional shoulder radiography with improvement in pain and shoulder function after subacromial injections.

SUBJECTS AND METHODS

We conducted a prospective outcomes study including 98 consecutive patients after fluoroscopy-guided subacromial injections who returned outcome questionnaires and who underwent routine shoulder radiography. Numeric pain rating scale (NRS) data were collected before and, along with patient global impression of change (PGIC) data, at 1 week and 1 month after injection. Outcome differences were assessed using the Student t test and Mann-Whitney U test. Logistic regression analysis was done, including radiographic variables compared with the outcome improvement. The odds ratios with 95% CIs were identified for the significant predictors.

RESULTS

A significant difference in overall improvement was found depending on the posterior acromial slope. Patients with a slope of more than 36° had significantly lower NRS and PGIC scores at 1 week and 1 month (p < 0.025) compared with those with a slope of 36° or less, with 86.4% of patients with a slope of more than 36° reporting significant improvement at 1 month. This was the only variable linked with improvement in the logistic regression analysis, with an odds ratio of 2.16 (95% CI, 1.11-4.22). Patients with calcific tendinitis had significantly lower NRS scores at both 1 week and 1 month (p = 0.03 and 0.05, respectively) and PGIC scores at 1 week (p = 0.05).

CONCLUSION

A posterior acromial slope of more than 36° and the presence of calcific tendinitis on conventional shoulder radiography are associated with better outcomes. Patients with a slope of more than 36° showed the best improvement.

Relationship of radiographic acromial characteristics and rotator cuff disease: a prospective investigation of clinical, radiographic, and sonographic findings

BACKGROUND

Many studies have attempted to correlate radiographic acromial characteristics with rotator cuff tears, but the results have not been conclusive. Therefore, the purpose of this study was to determine the relationship between rotator cuff disease and the development of symptoms with different radiographic acromial characteristics, including shape, index, and presence of a spur.

MATERIALS AND METHODS

The records of 216 patients enrolled in an ongoing prospective, longitudinal study investigating asymptomatic rotator cuff tears were reviewed. All patients underwent standardized radiographic evaluation, clinical evaluation, and shoulder ultrasonography at regularly scheduled surveillance visits. Three blinded observers reviewed all radiographs to determine the acromial morphology, presence, and size of an acromial spur, as well as the acromial index. These findings were analyzed to determine an association with the presence of a full-thickness rotator cuff tear.

RESULTS

The 3 observers demonstrated poor agreement for acromial morphology (κ = 0.41), substantial agreement for the presence of an acromial spur (κ = 0.65), and excellent agreement for the acromial index (κ = 0.86). The presence of an acromial spur was highly associated with the presence of a full-thickness rotator cuff tear (P = .003), even after adjusting for age. No association was found between the acromial index and rotator cuff disease (P = .92).

CONCLUSION

The presence of an acromial spur is highly associated with the presence of a full-thickness rotator cuff tear in symptomatic and asymptomatic patients. The acromial morphology classification system is an unreliable method to assess the acromion. The acromial index shows no association with the presence of rotator cuff disease.

Rotator cuff tears: association with acromion angulation on MRI

OBJECTIVE

Using magnetic resonance imaging (MRI), evaluate the correlation of acromion angulation with thickening of the coracoacromial ligament (CAL) and narrowing of the subacromial space resulting in impingement upon the rotator cuff tendons.

MATERIALS AND METHODS

Eighty-nine shoulder MRI studies performed on a 3T scanner were retrospectively analyzed by two blinded independent reviewers. Measurements of the acromion angle (delta angle), CAL thickness and distance between the CAL and humeral head were obtained. The data were categorized into two groups, delta angle less that and greater than 7.5°. The presence or absence of full thickness (FT) or near full thickness (NFT) rotator cuff tears was noted.

RESULTS

In group 1, the acromion angle varied from -6.8 to 6.8° (1.7±3.5°) with a CAL thickness of 0.91±0.20 mm and a subacromial distance of 6.47±0.88 mm. Group 2 acromion angle varied from 7.6° to 46.8° (18.0°±8.1°) with a CAL of 1.77±0.51 mm and a subacromial distance of 4.52±0.82 mm. The difference in CAL thickness and subacromial distance were significantly different between the two groups (P<.001). In Group 1, 3 out of 51 patients had a FT or NFT tear of the rotator cuff compared to 20 out of 38 in Group 2 (P<.001). There was no significant interobserver variability.

CONCLUSION

Steep acromion angulation is associated with CAL thickening and narrowing of the subacromial space. Patients with a steep acromion angle had a statistically increased incidence of rotator cuff tears.

Magnetic resonance imaging of rotator cuff disease and external impingement

Magnetic resonance (MR) imaging plays a major role in helping to identify rotator cuff disease and in demonstrating the pathology associated with external impingement. Many surgeons rely on MR imaging to assist in decision making and presurgical planning for patients with rotator cuff pain. This article reviews the etiology of external impingement and rotator cuff tears, and describes the MR imaging appearance of the normal and the pathologic rotator cuffs. It focuses on the supraspinatus tendon because this is the tendon involved in 95% of rotator cuff tears.

Observer variability in the assessment of the acromiohumeral interval using anteroposterior shoulder radiographs

BACKGROUND

An acromiohumeral interval narrower than 6 mm measured on AP shoulder radiographs has been considered pathological and suggestive of rotator cuff tears. This prospective study was conducted to assess inter- and intraobserver variation in the radiographic assessment of the acromiohumeral interval and its critical value on routinely taken AP shoulder radiographs off-study use to evaluate the accuracy of this measurement method.

METHODS

The acromiohumeral distance from the inferior anterior acromial aspect to the humeral head was measured in millimeters. Thirty blinded, anteroposterior shoulder radiographs were independently reviewed by five board-certified orthopedic shoulder surgeons at two time points in random order.

RESULTS

The results of three investigators showed significant intraobserver variation. Five investigator pairs showed significant interobserver variation at both examination time points. The maximum interobserver difference for the same radiograph was 8 mm (range 0 to 8 mm).

CONCLUSION

Our results indicate that the assessment of the acromiohumeral interval using non-standardized anteroposterior radiographs off-study use cannot be seen as a reproducible and reliable method of measurement.

Study protocol subacromial impingement syndrome: the identification of pathophysiologic mechanisms (SISTIM)

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 pathology (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.

Subacromial impingement syndrome

Subacromial impingement syndrome (SIS) represents a spectrum of pathology ranging from subacromial bursitis to rotator cuff tendinopathy and full-thickness rotator cuff tears. The relationship between subacromial impingement and rotator cuff disease in the etiology of rotator cuff injury is a matter of debate. Both extrinsic compression and intrinsic degeneration may play a role. Management includes physical therapy, injections, and, for some patients, surgery. There remains a need for high-quality studies of the pathology, etiology, and management of SIS.

Supervised exercises compared with radial extracorporeal shock-wave therapy for subacromial shoulder pain: 1-year results of a single-blind randomized controlled trial

BACKGROUND

Evidence from a recent randomized controlled trial indicated that supervised exercises (SE) were more effective than radial extracorporeal shock-wave therapy (rESWT) for the treatment of subacromial shoulder pain in the short to medium term. Little knowledge exists about the long-term results of rESWT for subacromial pain.

OBJECTIVE

The aim of this study was to evaluate the results of rESWT and SE provided to patients with subacromial shoulder pain after 1 year.

DESIGN

This was a single-blind randomized controlled trial.

SETTING

The study was conducted in the outpatient clinic of the Physical Medicine and Rehabilitation Department at Oslo University Hospital, Ullevaal, Norway.

PATIENTS

One hundred four patients with subacromial shoulder pain lasting at least 3 months participated. Patients were randomly assigned to either an rESWT group (n=52) or an SE group (n=52).

INTERVENTION

The rESWT intervention consisted of one session weekly for 4 to 6 weeks. The SE intervention consisted of two 45-minute sessions per week for up to 12 weeks.

MEASUREMENTS

The primary outcome measure was the Shoulder Pain and Disability Index. Secondary outcome measures were questions regarding pain and function and work status.

RESULTS

After 1 year, an intention-to-treat analysis showed no significant differences between the 2 groups for the primary outcome measure (-7.6 points, 95% confidence interval=-16.6 to 0.5) and pain, function, and medication use. Twenty-nine participants (60%) in the SE group versus 24 participants (52%) in the rESWT group were categorized as clinically improved. Thirty-eight participants in the SE group were at work compared with 30 participants in the rESWT group (odds ratio=1.1, 95% confidence interval=1.0 to 1.2). Fewer patients in the SE group had received additional treatments between 18 weeks and 1 year.

LIMITATIONS

The lack of a placebo control group, the lack of a cost-benefit analysis, and the small sample size were limitations of the study.

CONCLUSION

No significant difference was found between the SE and rESWT groups at the 1-year follow-up. More participants in the SE group had returned to work.

Reliability study of the sonographic measurement of the acromiohumeral distance in symptomatic patients

BACKGROUND

The purpose of this study was to evaluate the inter- and intra-observer reliability and accuracy of sonographic (US) acromiohumeral distance (AHD) measurement for both experienced and novice operators in US in patients suffering from subacromial impingement syndrome.

METHOD

A total of 43 patients (50 shoulders) diagnosed with subacromial impingement syndrome were recruited from an orthopedic outpatient clinic. The US measurement of AHD was obtained consecutively in a neutral position and in a 60 degrees abduction position. A total of 300 blinded measurements were taken.

RESULT

In the neutral abduction group the intra- observer interclass correlation coefficient (ICC) was 0.94 for the experienced operator and 0.92 for the novice operator. The inter-observer ICC was 0.70 and the accuracy was 1.1 mm. In the 60 degrees abduction group, the intra-observer ICC was 0.90 for the experienced operator and 0.87 for the novice operator. The inter-observer ICC was 0.64 and the accuracy was 1.4 mm. All ICCs were significant at a level of p < 0.0001.

CONCLUSION

The inaccuracy of the method was 1 mm regardless of the experience of the observer. US AHD measurement in patients with shoulder complaints is not as accurate as reported in healthy subjects. This may have important implications for the clinical use of this parameter.

Deltoid muscular flap transfer for the treatment of irreparable rotator cuff tears

The purpose of this study was to evaluate the outcome of deltoid muscle flap transfer for the treatment of irreparable rotator cuff tears. In a retrospective study 20 consecutive patients were evaluated. The index procedure took place between 2000 and 2003. Fifteen patients were male, mean age was 62 years. Inclusion criterion was a rotator cuff defect Bateman grade IV. Exclusion criteria were smaller defects, shoulder instability and fractures of the injured shoulder. An open reconstruction with acromioplasty and a pedicled delta flap was performed. Follow up period was mean 42 months. Follow-up included clinical examination, Magnetic Resonance Imaging (MRI) and the Constant and Simple (CS) shoulder tests. According to the Constant shoulder test the results were good in 13 patients, fair in 5 and unsatisfactory in 2. The pre-operative Constant Score improved from mean 25.7 points (±5.3) to 72.3 (±7.8) at follow-up. The mean values for the subcategories of CS increased significantly from 3.9 to 14.4 points for pain and from 4.2 to 15.9 points for activities daily routine (p<0.05). The change in range of motion and strength were not significant (p>0.05). Results of the Simple Shoulder Test showed a significant increase of the mean values from pre-operative 4.3 to 14.7 points post-operatively. MRI showed a subacromial covering of the defect in all cases, all flaps where intact on MRI but always the flap showed marked fatty degeneration. In conclusion, the delta flap is a simple method for the repair of large defects of the rotator cuff leading to satisfying medium results.