Efficacy of Imaging Modalities Assessing Fatty Infiltration in Rotator Cuff Tears

Risk factors for healing failure after arthroscopic rotator cuff repair in small to medium-sized tears: a retrospective cohort study

Objectives

To identify risk factors for tendon healing failure following arthroscopic rotator cuff repair (ARCR) in patients with small to medium-sized rotator cuff tears (RCTs).

Methods

A retrospective study was conducted on 320 patients with RCTs who underwent arthroscopic repair between June 2018 and June 2021. All patients had at least 2 years of postoperative follow-up, with MRI scans at the final assessment. Based on MRI results, patients were categorized into the healing success group (Group A: types I-III) or the healing failure group (Group B: types IV-V). Variables associated with rotator cuff healing, including patient characteristics, baseline symptoms, imaging data, and surgery-related factors, were analyzed using univariate and multivariate logistic regression.

Results

Healing failure occurred in 54 of the 320 patients (16.9%). Functional status improved significantly across all patients (P < 0.05), irrespective of healing outcomes. Multifactorial analysis identified smoking (OR = 1.931, P = 0.028), diabetes (OR = 3.517, P = 0.038), lower bone mineral density (BMD) (OR = 1.551, P = 0.018), higher fatty infiltration (FI) (OR = 4.025, P = 0.009), and smaller acromiohumeral distance (AHD) (OR = 2.546, P = 0.006) as independent risk factors for healing failure.

Conclusions

Smoking, diabetes, lower BMD, higher FI, and smaller AHD are independent risk factors for healing failure following ARCR.

Quantitative ultrasound assessment of fatty infiltration of the rotator cuff muscles using backscatter coefficient

BACKGROUND

To prospectively evaluate ultrasound backscatter coefficients (BSCs) of the supraspinatus and infraspinatus muscles and compare with Goutallier classification on magnetic resonance imaging (MRI).

METHODS

Fifty-six participants had shoulder MRI exams and ultrasound exams of the supraspinatus and infraspinatus muscles. Goutallier MRI grades were determined and BSCs were measured. Group means were compared and the strength of relationships between the measures were determined. Using binarized Goutallier groups (0-2 versus 3-4), areas under the receiver operating characteristic curves (AUROCs) were calculated. The nearest integer cutoff value was determined using Youden's index.

RESULTS

BSC values were significantly different among most Goutallier grades for the supraspinatus and infraspinatus muscles (both p < 0.001). Strong correlations were found between the BSC values and Goutallier grades for the supraspinatus (τb = 0.72, p < 0.001) and infraspinatus (τb = 0.79, p < 0.001) muscles. BSC showed excellent performance for classification of the binarized groups (0-2 versus 3-4) for both supraspinatus (AUROC = 0.98, p < 0.0001) and infraspinatus (AUROC = 0.98, p < 0.0001) muscles. Using a cutoff BSC value of -17 dB, sensitivity, specificity, and accuracy for severe fatty infiltration were 87.0%, 90.0%, and 87.5% for the supraspinatus muscle, and 93.6%, 87.5%, and 92.7% for the infraspinatus muscle.

CONCLUSION

BSC can be applied to the rotator cuff muscles for assessment of fatty infiltration. For both the supraspinatus and infraspinatus muscles, BSC values significantly increased with higher Goutallier grades and showed strong performance in distinguishing low versus high Goutallier grades.

RELEVANCE STATEMENT

Fatty infiltration of the rotator cuff muscles can be quantified using BSC values, which are higher with increasing Goutallier grades.

KEY POINTS

Ultrasound BSC measurements are reliable for the quantification of muscle fatty infiltration. BCS values increased with higher Goutallier MRI grades. BCS values demonstrated high performance for distinguishing muscle fatty infiltration groups.

Ultrasound Versus Magnetic Resonance Imaging as First-Line Imaging Strategies for Rotator Cuff Pathologies: A Comprehensive Analysis of Clinical Practices, Economic Efficiency, and Future Perspectives

Rotator cuff injuries are a prevalent cause of atraumatic chronic shoulder pain, imposing a significant healthcare burden. This article reviews the clinical presentation, diagnostic imaging modalities, practice variations, and economic efficiency considerations in the evaluation of rotator cuff pathologies. Ultrasound (US) and magnetic resonance imaging (MRI) are the primary imaging methods for diagnosing rotator cuff injuries. US provides real-time visualization but has limited tissue penetration, while MRI offers detailed anatomical information but is not a dynamic process. Studies show that MRI is superior to US with higher sensitivity and specificity. MRI is the gold standard, particularly for surgical planning, but US remains relevant when MRI is not feasible. Both require standardized protocols for evaluating tear dimensions and muscle atrophy. With the operator-dependent nature of US, MRI offers a more comprehensive assessment of rotator cuff tears and predictive insights for clinical outcomes. Practice variations exist in the management of rotator cuff pathologies, with some countries favoring US as the primary imaging modality and others relying more on MRI. These variations are influenced by factors like resource availability and healthcare system nuances. In Australia, current guidelines lean toward conservative management, potentially leading to delayed diagnoses and increased costs. The United States often favors MRI, while Canada advocates for US as the initial choice. Economic considerations play a significant role in selecting imaging modalities. While US is cost-effective, it may necessitate subsequent MRI examinations, contributing to inefficiencies in the diagnostic process. Studies suggest that a combined approach of US and MRI is less efficient and cost-effective than MRI alone. However, the use of both modalities rather than MRI alone is common in clinical practice, adding to healthcare expenses. In conclusion, the choice of imaging modality for rotator cuff pathologies should consider factors such as diagnostic efficacy, cost-effectiveness, and resource availability. Radiologists play a pivotal role in guiding this selection and ensuring comprehensive evaluations. Future considerations should include the revision of management guidelines and the potential inclusion of shoulder pathologies in healthcare coverage to optimize patient care and healthcare expenditure.

Emerging Role of Quantitative Ultrasound-Based Imaging Techniques for Characterizing Rotator Cuff Tears: A Scoping Review

Rotator cuff myosteatosis following cuff tears is very common and one of the most important prognostic factors in clinical management. Quantitative ultrasound-based imaging techniques (QUBIT) are frequently used along with magnetic resonance imaging (MRI) to evaluate rotator cuff fatty degeneration. However, the examination of rotator cuff tissue integrity by QUBIT is lacking a standardized imaging protocol and procedural methodologies. In this scoping review, we synthesized the current state of QUBIT against the reference imaging modalities in patients with rotator cuff tears. The literature search was extracted from 963 studies, with 22 studies included in the final review in accordance with the preferred reporting items for systematic reviews and meta-analyses extensions for scoping reviews. The selected studies included human participants and focused on measuring at least one prognostic or diagnostic factor using ultrasonography-based imaging with reference to MRI. The findings suggest both conventional B-mode ultrasound and shear wave elastography imaging were comparable to MRI-based imaging techniques for the evaluation of fatty infiltration and rotator cuff tear characterization. This review establishes guidelines for reporting shoulder-specific QUBIT aimed at developing a standardized imaging protocol. The objective was to enhance the diagnostic and prognostic capabilities of QUBIT in the clinical setting.

Radial extracorporeal shockwave therapy reduces pain and promotes proximal tendon healing after rotator cuff repair: Randomized clinical trial

BACKGROUND

Extracorporeal shockwave therapy (ESWT) is widely used to treat soft tissue disorders, but evidence for its application after rotator cuff (RC) repair is lacking.

OBJECTIVES

To investigate the effect of ESWT on short-term functional and structural outcomes after RC repair.

METHODS

Thirty-eight individuals were randomly assigned to the ESWT group (n = 19) or control group (n = 19) 3 months after RC repair. Both groups underwent 5 weeks of advanced rehabilitation and participants in the ESWT group additionally received 2000 pulses of shockwave therapy every week for 5 weeks. The primary outcome was pain measured on a visual analog scale (VAS). Secondary outcomes were range of motion (ROM), Constant score, University of California Los Angeles score (UCLA), American Shoulder and Elbow Surgeons form (ASES), and Fudan University shoulder score (FUSS). Changes in signal/noise quotient (SNQ), muscle atrophy and fatty infiltration were analyzed from MRI. All participants underwent clinical and MRI examinations 3 months (baseline) and 6 months (follow-up) post repair.

RESULTS

A total of 32 participants completed all assessments. Pain and function improved in both groups. At 6 months post repair, pain intensity was lower and ASES scores higher in the ESWT than in the control group (all p-values < 0.01). SNQ near the suture anchor site decreased significantly from baseline to follow-up in the ESWT group (p = 0.008) and was significantly lower than that in the control group (p = 0.036). Muscle atrophy and the fatty infiltration index did not differ between groups.

CONCLUSION

ESWT and exercise more effectively reduced early shoulder pain than rehabilitation alone and accelerated proximal supraspinatus tendon healing at the suture anchor site after RC repair. However, ESWT may not be more effective than advanced rehabilitation in terms of functional outcomes at the short-term follow-up.

Radiodensity measurement is feasible for evaluating fatty infiltration in hip abductors

OBJECTIVE

This retrospective study aimed to compare radiodensity measurements and Goutallier grading systems for the evaluation of fatty infiltration in hip abductors.

METHODS

The radiodensity of the gluteus minimus and medius muscles was measured in 80 hips of 40 patients. These muscles were graded for fatty infiltration using three five-grade classification systems: the original Goutallier classification on both computed tomography (CT) and magnetic resonance imaging (MRI), and a new objective classification based on the percentage of the functional muscle area (defined as 30-100 Hounsfield units). After measuring and grading the abductors, correlation coefficients between them were analyzed.

RESULTS

Spearman's rank correlation coefficients (ρ) between radiodensity measurements of abductors and the Goutallier classification on CT and MRI were -0.701 and -0.552 for the gluteus minimus and -0.832 and -0.740 for the gluteus medius, respectively. Our new classification had correlation coefficients of -0.844 and -0.926 for the gluteus minimus and gluteus medius, respectively.

CONCLUSIONS

Radiodensity measurements showed a strong correlation with the grading systems, particularly with the new classification based on the percentage of the functional muscle area. Considering the subjective nature of the original Goutallier grading systems, we conclude that radiodensity assessment is feasible and more objective for evaluating fatty infiltration in hip abductors.

Rotator cuff fatty infiltration and muscle atrophy: relation to glenoid deformity in primary glenohumeral osteoarthritis

BACKGROUND

Muscle atrophy (MA) and fatty infiltration (FI) are degenerative processes of the rotator cuff musculature that have incompletely understood relationships with the development of eccentric glenoid wear in the setting of primary glenohumeral osteoarthritis (GHOA).

METHODS

All patients with GHOA and an intact rotator cuff who underwent both magnetic resonance imaging and computed tomography scans of the affected shoulder prior to total shoulder arthroplasty between 2015 and 2020 were identified from a prospectively maintained registry. Rotator cuff MA was measured quantitatively on sequential sagittal magnetic resonance images, whereas FI was assessed on sagittal magnetic resonance imaging slices using the Goutallier classification. Preoperative computed tomography scans were reconstructed using automated 3-dimensional software to determine glenoid retroversion, glenoid inclination, and humeral head subluxation. Glenoid deformity was classified according to the Walch classification. Univariate and multivariable regression analyses were performed to characterize associations between age, sex, muscle area, FI, and glenoid morphology.

RESULTS

Among the 127 included patients, significant associations were found between male sex and larger overall rotator cuff musculature (P < .01), increased ratio of the posterior rotator cuff (PRC) to the subscapularis area (P = .01), and glenoid retroversion (19° vs. 14°, P < .01). Larger supraspinatus and PRC muscle size was correlated with increased retroversion (r = 0.23 [P = .006] for supraspinatus and r = 0.25 [P = .004] for PRC) and humeral head subluxation (r = 0.25 [P = .004] for supraspinatus and r = 0.28 [P = .001] for PRC). The ratio of PRC muscle size to anterior rotator cuff muscle size was not associated with evidence of eccentric glenoid wear (P > .05). After we controlled for confounding factors, increasing glenoid retroversion was associated with high-grade infraspinatus FI (β, 6.8; 95% confidence interval, 2.9-10.7; P < .01) whereas larger PRC musculature was predictive of a Walch type B (vs. type A) glenoid (odds ratio, 1.3; 95% confidence interval, 1.0-1.5; P = .04).

CONCLUSION

Patients with eccentric glenoid wear in the setting of primary GHOA and an intact rotator cuff appear to have both larger PRC musculature and higher rates of infraspinatus FI. Although the temporal and causal relationships of these associations remain ambiguous, MA and FI should be considered 2 discrete processes in the natural history of GHOA.

Fatty degeneration of the rotator cuff: pathogenesis, clinical implications, and future treatment

Chronic rotator cuff pathology is often complicated by fatty degeneration of the rotator cuff (FDRC) muscles, an insidious process associated with poor prognosis with or without surgical intervention. Currently there is no treatment for FDRC, and many studies have described a natural course for this disease almost always resulting in further degeneration and morbidity. Recapitulating FDRC using animal injury models, and using imaging-based studies of human FDRC, the pathophysiology of this disease continues to be further characterized. Researchers studying mesenchymal stem cell-derived progenitor cells and known fibrogenic and adipogenic signaling pathways implicated in FDRC seek to clarify the underlying processes driving these changes. While new cell- and molecular-based therapies are being developed, currently the strongest available avenue for improved management of FDRC is the use of novel imaging techniques which allow for more accurate and personalized staging of fatty degeneration. This narrative review summarizes the evidence on the molecular and pathophysiologic mechanisms of FDRC and provides a clinical update on the diagnosis and management of this condition based on the existing knowledge. We also sought to examine the role of newer biologic therapies in the management of RC fatty degeneration and to identify areas of future research.

The Evolving Roles of MRI and Ultrasound in First-Line Imaging of Rotator Cuff Injuries

Rotator cuff tears are the most likely source of shoulder pain in adults and may cause protracted disability. Management of rotator cuff tears is associated with considerable costs. Accurate diagnosis can guide surgical planning and help achieve a favorable clinical outcome. While radiographs remain the initial imaging test for shoulder injury, the roles of MRI and ultrasound (US) as first-line imaging after radiography are evolving. This review leverages current literature and the practical experience of subspecialty musculoskeletal radiologists from different institutions in describing a practical approach to imaging rotator cuff pathology. Both MRI and US are accurate for identifying rotator cuff tears, but each has advantages and shortcomings. As both modalities currently represent reasonable first-line approaches, considerable practice variation has evolved. Given the low cost of US, imagers should strive to optimize the quality of shoulder US examinations and to build referrer confidence in this modality. The roles of direct CT and MR angiography, as well as imaging evaluation of the postoperative rotator cuff, are also considered. Through careful selection among the available imaging modalities, as well as optimal performance and interpretation of such examinations, radiologists can positively contribute to the diagnosis and treatment of patients with rotator cuff injuries.

Surgical outcomes and complications following distal biceps tendon reconstruction: a systematic review and meta-analysis

Background

Primary repair of chronic distal biceps tendon ruptures may not be possible because of tendon retraction, and there remains no clear consensus on the type of reconstruction technique used. The purpose of this study was to report the clinical outcomes and complication rates following reconstruction of chronic distal biceps tendon ruptures.

Methods

A systematic review was performed following PRISMA guidelines. The following databases were searched: Embase, MEDLINE, and Cochrane Central Register of Controlled Trials. The primary outcomes of interest included range of motion, strength, and functional outcome scores. Secondary outcomes included complication, reoperation, and revision rates. Outcomes and complication rates of each graft type and fixation technique were aggregated and compared with nonparametric Wilcoxon signed rank and rank sum tests. Spearman rank coefficients were calculated for time from injury to surgery on all outcomes.

Results

There were no significant differences found between the graft type or fixation technique for postoperative range of motion, strength, and patient-reported outcomes. Postoperative complications were substantially higher in the autograft group (34%) as compared to the allograft group (14%). The fixation technique used also demonstrated a significantly increased complication rate in the weave group compared with the onlay group (34% and 9%, respectively).

Conclusion

Our results do not reveal any statistically significant differences between groups in the primary outcomes. However, substantially higher complication rates were observed in the autograft and weave cohorts; more than half of the complications related to the use of autograft were associated with donor site morbidity. No specific graft type was identified as superior, although this may be due to the small patient numbers included within this study.