Imaging of Reparable and Irreparable Rotator Cuff Tears

This review offers a comprehensive discussion of magnetic resonance imaging (MRI) for the assessment of rotator cuff tendon repair and joint-preserving surgical options for patients with irreparable rotator cuff tears. Deciding to proceed with arthroscopic repair of a rotator cuff tendon tear is impacted both by clinical factors and morphological imaging features. Preoperative clinical and imaging features also predict the likelihood of success of a rotator cuff tendon repair and are important to recognize. In patients with irreparable rotator cuff tears and relatively preserved glenohumeral cartilage, various joint-preserving surgical options are available and seen increasingly in clinical practice.The acceptable range of postoperative imaging findings correlating with a functionally intact rotator cuff repaired tendon, and MRI findings that are either suggestive of or definitive for rotator cuff tendon repair failure are discussed in detail, with attention to the Sugaya classification. Ancillary features, such as progressive retraction of the myotendinous junction and the degree of muscle fatty atrophy, can be used as problem-solving tools in cases equivocal for rotator cuff retear. Finally, this review discusses in detail the most common joint-preserving treatment options for patients with irreparable rotator cuff tears, including an in-depth focus on superior capsular reconstruction.

Role of ultrasound and MRI in the evaluation of postoperative rotator cuff

Rotator cuff tears are common shoulder injuries in patients above 40 years of age, causing pain, disability, and reduced quality of life. Most recurrent rotator cuff tears happen within three months. Surgical repair is often necessary in patients with large or symptomatic tears to restore shoulder function and relieve symptoms. However, 25% of patients experience pain and dysfunction even after successful surgery. Imaging plays an essential role in evaluating patients with postoperative rotator cuff pain. The ultrasound and magnetic resonance imaging are the most commonly used imaging modalities for evaluating rotator cuff. The ultrasound is sometimes the preferred first-line imaging modality, given its easy availability, lower cost, ability to perform dynamic tendon evaluation, and reduced post-surgical artifacts compared to magnetic resonance imaging. It may also be superior in terms of earlier diagnosis of smaller re-tears. Magnetic resonance imaging is better for assessing the extent of larger tears and for detecting other complications of rotator cuff surgery, such as hardware failure and infection. However, postoperative imaging of the rotator cuff can be challenging due to the presence of hardware and variable appearance of the repaired tendon, which can be confused with a re-tear. This review aims to provide an overview of the current practice and findings of postoperative imaging of the rotator cuff using magnetic resonance imaging and ultrasound. We discuss the advantages and limitations of each modality and the normal and abnormal imaging appearance of repaired rotator cuff tendon.

Rotator Cuff Injury and Repair

Rotator cuff pathology is a commonly encountered clinical and radiologic entity that can manifest as tendinopathy or tearing. Magnetic resonance imaging (MRI) and ultrasonography offer similar sensitivity and specificity for the evaluation of the native rotator cuff, and the chosen modality may vary, depending on local practice and accessibility. MR arthrography is frequently used in the postoperative setting as a problem-solving tool. Key findings to include in the preoperative MRI report include the size and location of the tear, thickness of the tendon involved (partial versus full thickness), and overall tendon quality. The report should also address features associated with poor surgical outcomes, such as fatty atrophy, a decreased acromiohumeral interval, and evidence of rotator cuff arthropathy. Musculoskeletal radiologists should be familiar with the various surgical techniques and expected postoperative imaging appearance of rotator cuff repairs. Imaging also plays a role in identifying recurrent tearing, graft failure, hardware loosening, infection, and other complications.

Posttreatment Imaging of the Shoulder

The shoulder joint is vulnerable for injuries following trauma and in the context of sporting activities. Degenerative rotator cuff disease is also a common entity. Conservative therapy is often not indicated or does not lead to the desired success, so surgical intervention is necessary. Routine follow-ups, but also persistent complaints, delayed healing, or recurrent trauma, usually need postoperative imaging of the shoulder. The choice of the adequate imaging modality and technique is important to reach the correct diagnosis. Additionally, knowledge of the most common surgical procedures, as well as typical normal findings and expected pathologies on different imaging modalities, is crucial for the radiologist to play a relevant role in the postoperative diagnostic process. This article addresses postoperative imaging after rotator cuff repair, shoulder arthroplasty, and surgery for shoulder stabilization with an emphasis on computed tomography and magnetic resonance imaging.

Allograft and autograft provide similar retear rates for the management of large and massive rotator cuff tears: a review and meta-analysis

PURPOSE

Currently, autografts and allografts are largely used to treat large or massive rotator cuff tear (RCT), without any evidence in favour of one graft or the other. The purpose of this study was to determine the rate of retear of autograft and allograft in the treatment of large or massive posterosuperior RCT.

METHOD

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed to perform this systematic review and meta-analysis of the results in the literature as well as the presentation of results. A search of the literature was performed in the electronic databases MEDLINE, Scopus, Embase, and the Cochrane Library. The quality of the included studies was evaluated according to the MINORS (Methodological Index for Nonrandomized Studies) score. Inclusion criteria were studies in English evaluating clinical and radiological results of surgical treatment with autograft or allograft for large or massive RCT since 2008. The main criterion was the retear rate of the graft assessed on MRI or US scan at 1-year minimum follow-up. Partial tear were classified as "tear".

RESULTS

The overall retear rate was 23.6% (15.5-32.7) at a mean follow-up of 18.4 ± 7.8 (12-36) months. There was no significant difference between the two kinds of graft, with a retear rate of 27.0% (15.4-40.2) and 20.9% (9.9-34.2) with autograft and allograft respectively (n.s.). Similar improvements of functional scores (+ 28.8 to 38.4 points for the Constant score, + 33.6 to 38.4 points for the ASES, and - 4.0 to - 4.1 points for pain-VAS) were reported in the two groups after at 27.2 ± 11.1 (12-48) months. The rate of complications except retear was 1.8% (0.2, 3.7) with autograft and 0.5% (0.8, 1.8) with allograft (n.s.).

CONCLUSION

The use of autograft and allograft for the treatment of large or massive RCT leads to similar retear rate and clinical outcomes at short to medium terms.

LEVEL OF EVIDENCE

Level IV.

Comparative Analysis of Real-Time Dynamic Ultrasound and Magnetic Resonance Imaging in the Diagnosis of Rotator Cuff Tear Injury

Objective

To explore the value of real-time dynamic ultrasound and magnetic resonance imaging (MRI) in the diagnosis of rotator cuff injury.

Methods

From January 2020 to June 2021, the clinical data of 55 patients with rotator cuff injury were collected. All patients were examined by real-time dynamic ultrasound and MRI at the same time within two weeks before surgery, which was confirmed by arthroscopy. The value of real-time dynamic ultrasound, MRI, and the real-time dynamic ultrasound combined with MRI in the diagnosis of rotator cuff injury was evaluated.

Results

Among the 55 patients with rotator cuff injury, real-time dynamic ultrasound showed full-thickness rotator cuff tear in 12 patients (21.82%), including type I in 2 patients (3.64%), type II in 6 patients (10.91%), and type III in 4 patients (7.27%), and partial rotator cuff tear in 31 patients (56.36%), including type IV in 16 patients (29.00%), type V in 5 patients (9.09%), and type VI in 10 patients (18.18%). MRI showed full-thickness rotator cuff tear in 12 patients (21.82%), including type I in 2 patients (3.64%), type II in 6 patients (10.91%), and type III in 4 patients (7.27%), and partial rotator cuff tear in 37 patients (67.27%), including type IV in 20 patients (36.36%), type V in 7 patients (12.73%), and type VI in 10 patients (18.18%). The combined examination showed full-thickness rotator cuff tear in 12 patients (21.82%), including type I in 2 patients (3.64%), type II in 6 patients (10.91%), and type III in 4 patients (7.27%), and partial rotator cuff tear in 39 cases (70.91%), including type IV in 21 cases (38.12%), type V in 7 patients (12.73%), and type VI in 12 patients (21.82%). The diagnostic accuracy of real-time dynamic ultrasound in complete tearing, partial tearing and the overall accuracy were 92.31%, 73.81% and 78.18%, respectively. The diagnostic accuracy of complete tear, partial tear and the overall accuracy of MRI were 92.31%, 88.00% and 89.09%, respectively. The diagnostic accuracy of complete tear and partial tear and overall accuracy in the real-time dynamic ultrasound combined with MRI were 92.31%, 95.24%, and 94.55%, respectively. The diagnostic accuracy and overall diagnostic accuracy of the combined examination of partial tears were higher than those of the real-time dynamic ultrasound and MRI examinations alone.

Conclusion

Real-time dynamic ultrasound and MRI have high application value in the diagnosis of rotator cuff injury, and the combined diagnosis is conducive to improving the diagnostic accuracy of patients with partial tear.

An OrthoRadiological review of superior capsularreconstruction in the shoulder

Superior capsular reconstruction (SCR) is an emerging surgical technique used to treat patients with irreparable rotator cuff tears. In this procedure, a graft is attached between the superior glenoid and the greater tuberosity, with the aim of optimising glenohumeral joint function and stability. Pre-operative radiological evaluation of patients having such cuff tears is crucial for appropriate patient selection. Such imaging is particularly useful for the assessment of the cuff tear size and location, muscle wasting, fatty infiltration and the presence of any glenohumeral joint arthritis. In addition, post-operative imaging is useful in assessing graft integrity, with specific patterns of graft failure now being recognised on imaging. This article will discuss the indications and contraindications for this procedure, and review the biomechanical concepts of SCR in improving glenohumeral joint stability and restoring the force couples around the joint. The radiological appearances of the intact graft and the various patterns of graft failure will be illustrated, along with various radiological examples.

MRI of superior capsular reconstruction graft and associated short-term clinical outcomes in patients with massive irreparable rotator cuff tears

OBJECTIVE

To assess MRI appearance of the dermal allograft and its correlation with clinical outcome following superior capsular reconstruction (SCR).

MATERIALS AND METHODS

This is a retrospective study of patients who underwent SCR between 2015 and 2018. Patients with postoperative MRI and clinical follow-up were included. Exclusion criteria were preoperative shoulder instability, advanced glenohumeral arthritis, and lack of postoperative MRI or clinical follow-up. Radiographs and MRIs were evaluated for graft integrity and position, acromiohumeral interval, superior subluxation distance (SSD), and glenohumeral cartilage loss. Correlation between imaging and clinical outcome measures were assessed.

RESULTS

24 shoulders (23 patients) met the inclusion criteria at a mean clinical and MRI follow-up of 9.1 months. There were 12 intact grafts (50%) and 12 torn grafts (50%), most commonly at the glenoid attachment (8/12). Patients with graft tear had greater SSD (mean 10.5 ± 6.1 mm) than those without tear (mean 6.1 ± 3.8 mm) (p = 0.028). SSD > 7.9 mm had a 79% sensitivity and 91% specificity for graft tear. The intact grafts were more commonly covering the superior humeral head (91.7%) compared with the torn grafts (41.7%) (p = 0.027). There was improvement of clinical outcome measures including American Shoulder and Elbow Surgeons score (p = 0.005) and forward elevation (p = 0.021) although there was no correlation between clinical outcome and integrity of the graft.

CONCLUSION

SCR results in significant short-term clinical improvement even in the presence of graft tear on postoperative MRIs on current study. Gap between graft and the anchors, non-superior position of the graft, and humeral head superior subluxation can be associated with tear.

The subacromial balloon spacer for massive irreparable rotator cuff tears: approximately 3 years of prospective follow-up

BACKGROUND

Irreparable rotator cuff tears (RCT) are still a challenging problem. RCT can result in disability and severe pain. The optimal treatment for this disabling and painful diagnosis remains controversial. The arthroscopic implantation of a biodegradable subacromial balloon spacer is a possible treatment option. In this prospective study, we evaluate the clinical outcome of this balloon spacer after approximately 3 years.

METHODS

Between March 2014 and December 2015, the biodegradable balloon spacer was implanted into the subacromial space of 46 shoulders of 44 patients with massive irreparable RCT. Pain was evaluated using a numeric rating scale (NRS), and functional outcome was evaluated using the Oxford shoulder score (OSS). Patients were followed prospectively for approximately 3 years. This present study focuses on the comparison between the early and the midterm results up to approximately 3 years.

RESULTS

All patients were treated by surgical implantation of the subacromial balloon spacer. The comparison between the outcomes of the NRS and the OSS after one and 3 years was made and showed no mutual significant differences, respectively, p = 0.61 and p = 0.08. Significant pain reduction and functional improvement was noticed postoperatively and maintained after approximately 3 years. At last follow-up (mean: 34 months), pain was reduced to a NRS of 3.09 points (95% CI: 2.17-4.01). Functional outcome based on the OSS improved significantly from 21.32 preoperatively to 34.39 (95% CI: 29.17-36.70) at the last follow-up. Correction for estimated confounders did not show significant differences. 82% of the patients were satisfied with the outcome after implantation of the subacromial balloon spacer. No surgical or postoperative medical complications due to implantation of the balloon spacer were reported.

CONCLUSIONS

Arthroscopic implantation of the biodegradable balloon spacer in the subacromial space is a safe and minimally invasive intervention. It leads to significant reduction in pain and significant improvement of functional daily activities in patients with irreparable RCT during 3 years of follow-up starting postoperative and maintain over time beyond device degradation. A high percentage of patients are satisfied postoperatively. Despite of these positive results after 3 years of follow-up, the specific contribution of the balloon needs further investigation.

Clinical Importance of Graft Integrity in Arthroscopic Superior Capsular Reconstruction Using a Minimally Invasively Harvested Midthigh Fascia Lata Autograft: 3-Year Clinical and Magnetic Resonance Imaging Outcomes

BACKGROUND

The clinical importance of graft type and integrity in arthroscopic superior capsular reconstruction (ASCR) remains controversial.

PURPOSE

To assess 3-year clinical and magnetic resonance imaging (MRI) outcomes of ASCR using a minimally invasively harvested fascia lata autograft (FLA) for irreparable rotator cuff tears (IRCTs) and to determine the clinical importance of graft integrity and whether the results change from year 2 to 3.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 22 consecutive patients who underwent ASCR with a minimally invasively harvested FLA were enrolled in a prospective single-arm study. At 3 years, the patients answered a satisfaction questionnaire and underwent a clinical examination and MRI. The MRI scans were independently reviewed by 3 raters to determine the graft integrity, acromiohumeral interval, supraspinatus atrophy, and fatty degeneration of the rotator cuff muscles. Reliability statistics were calculated, and the outcomes were compared across subgroups of patients with and without complete graft tears.

RESULTS

Overall, 21 patients (95.5%) answered the questionnaire, 20/21 (95.2%) were satisfied, 4/20 (20.0%) reported donor site pain, and 19 patients (86.4%) underwent examinations. From preoperatively to 3 years, the mean improvement was 73.68° in elevation (95% CI, 47.59°-99.77°), 89.21° in abduction (95% CI, 66.56°-111.86°), 24.74° in external rotation (95% CI, 4.72°-34.75°), 3.00 in internal rotation (95% CI, 2.36-3.64), 2.61 kg in abduction strength (95% CI, 1.76-3.45 kg), 50.79 on the Constant score (CS; 95% CI, 41.99-59.58), 7.47 on the Simple Shoulder Test (SST; 95% CI, 5.19-9.75), and 36.05% on the subjective shoulder value (SSV; 95% CI, 23.19%-48.92%), which were all significant (P < .05). From 2 to 3 years, the mean improvement in abduction was 20.26° (95% CI, 5.44°-35.09°), which was significant (P = .010). At 3 years, the raters perfectly agreed (kappa = 1; P = .000013) that 4 patients (21.1%) had complete graft tears; this subgroup of patients had decreased external rotation strength at 90° of abduction (1.77 ± 0.17 vs 4.45 ± 2.55 kg, respectively; P = .027) and increased grades of infraspinatus (3.50 ± 0.58 vs 2.20 ± 1.01, respectively; P = .030) and teres minor fatty degeneration (3.25 ± 0.96 vs 1.53 ± 0.64, respectively; P = .005) compared with those without a complete graft tear, but the mean CS, SST, and SSV scores did not differ from those of the overall group (69.50 ± 5.20 vs 69.63 ± 18.25; 9.00 ± 2.31 vs 9.74 ± 4.73; and 72.50 ± 15.00 vs 71.58 ± 26.70, respectively).

CONCLUSION

The 3-year clinical outcomes of ASCR using a minimally invasively harvested FLA for IRCTs were good, despite donor site morbidity. Active abduction improved significantly from 2 to 3 years. Complete graft tears were correlated with significantly decreased external rotation strength at 90° of shoulder abduction and increased grades of infraspinatus and teres minor fatty degeneration.

REGISTRATION

NCT03663036 (ClinicalTrials.gov identifier).

The Postoperative Rotator Cuff

MR imaging interpretation following rotator cuff repair can be challenging and requires familiarity with various types of rotator cuff tear, their surgical treatments, normal postoperative MR imaging appearance, and complications. This article reviews the common surgical procedures for the reparable and nonreparable massive rotator cuff tears, their expected postoperative MR imaging findings, and imaging appearance of a range of complications.