Patterns of tendon retraction in full-thickness rotator cuff tear: comparison of delaminated and nondelaminated tendons

Automatic 3-dimensional analysis of posterosuperior full-thickness rotator cuff tear size on magnetic resonance imaging

BACKGROUND

Tear size and shape are known to prognosticate the efficacy of surgical rotator cuff (RC) repair; however, current manual measurements on magnetic resonance images (MRIs) exhibit high interobserver variabilities and exclude 3-dimensional (3D) morphologic information. This study aimed to develop algorithms for automatic 3D analyses of posterosuperior full-thickness RC tear to enable efficient and precise tear evaluation and 3D tear visualization.

METHODS

A deep-learning network for automatic segmentation of the tear region in coronal and sagittal multicenter MRI was trained with manually segmented (consensus of 3 experts) proton density- and T2-weighted MRI of shoulders with full-thickness posterosuperior tears (n = 200). Algorithms for automatic measurement of tendon retraction, tear width, tear area, and automatic Patte classification considering the 3D morphology of the shoulder were implemented and evaluated against manual segmentation (n = 59). Automatic Patte classification was calculated using automatic segmented humerus and scapula on T1-weighted MRI of the same shoulders.

RESULTS

Tears were automatically segmented, enabling 3D visualization of the tear, with a mean Dice coefficient of 0.58 ± 0.21 compared to an interobserver variability of 0.46 ± 0.21. The mean absolute error of automatic tendon retraction and tear width measurements (4.98 ± 4.49 mm and 3.88 ± 3.18 mm) were lower than the interobserver variabilities (5.42 ± 7.09 mm and 5.92 ± 1.02 mm). The correlations of all measurements performed on automatic tear segmentations compared with those on consensus segmentations were higher than the interobserver correlation. Automatic Patte classification achieved a Cohen kappa value of 0.62, compared with the interobserver variability of 0.56. Retraction calculated using standard linear measures underestimated the tear size relative to measurements considering the curved shape of the humeral head, especially for larger tears.

CONCLUSION

Even on highly heterogeneous data, the proposed algorithms showed the feasibility to successfully automate tear size analysis and to enable automatic 3D visualization of the tear situation. The presented algorithms standardize cross-center tear analyses and enable the calculation of additional metrics, potentially improving the predictive power of image-based tear measurements for the outcome of surgical treatments, thus aiding in RC tear diagnosis, treatment decision, and planning.

Mechanical strength of the rotator cuff and cable interface: a complete histological and biomechanical study

PURPOSE

This study sought to evaluate the biomechanical properties of the interface between the rotator cuff and the semicircular humeral ligament or rotator cable (RCa) using histological and biomechanical techniques.

METHODS

Out of 13 eligible cadaver specimens, 5 cadaver shoulders with an intact rotator cuff were included, 8 were excluded due to an injured rotator cuff. The histological study enables us to describe the capsule-tendon interface between the infraspinatus tendon (IST) or supraspinatus tendon (SST) and RCa, and to detect loose connective tissue layers to determine their precise location and measure their length along the interface. The biomechanical study sought to characterize and compare the mechanical strength of the IST-RCa versus SST-RCa interfaces.

RESULTS

The average thickness of the RCa was 1.44 ± 0.20 mm. The histological study revealed a loose connective tissue layer at the IST-RCa interface, a finding not observed at the SST-RCa interface. The biomechanical study showed that the rigidity of the SST-RCa interface (72.10-2 N/mm) was 4.5 times higher than for the IST-RCa interface (16.10-2 N/mm) and the average maximum forces reached were 19.0 N and 10.6 N for the SST-RCa and IST- RCa interfaces, respectively.

CONCLUSION

The IST-RCa interface consists of a loose connective tissue layer contrary to the SST-RCa interface. In parallel, two different groups in terms of the mechanical response were identified: the IST-RCa interface group had less rigidity and ruptured more quickly than the SST-RCa interface, therefore emerging as the most vulnerable interface and explaining a potential extension of rotator cuff tears.

The relationship between the duration and the retraction and atrophy grades in traumatic isolated full-thickness supraspinatus tears in young patients

BACKGROUND

The study aimed to determine the grade of retraction and atrophy according to the time elapsed in traumatic isolated full-thickness supraspinatus (SS) tears in young patients.

METHODS

One thousand twenty-six patients, who underwent arthroscopic shoulder surgery, were retrospectively reviewed. Pre-operative magnetic resonance imaging (MRI) of 69 patients aged 18 to 40 years with isolated traumatic full-thickness SS lesions remaining after exclusion criteria were evaluated for tendon retraction and atrophy grades. SS retraction was determined from a T2-weighted oblique coronal MRI slice, and the atrophy grade was determined from the T1-weighted oblique sagittal MRI slice. The patients were divided into four groups 0-1 month, 1-3 months, 3-6 months, and 6-12 months according to the time between trauma and MRI. The relationship of tendon retraction and muscle atrophy with elapsed time was evaluated, in addition, comparisons between groups were made.

RESULTS

Thirty-one (45%) of the patients were female and their mean age was 30 ± 7.3 (18-40) years. The mean age of men was 30.5 ± 6.9 (18-39) years (p = 0.880). The time between rupture and MRI was moderately correlated with retraction and strongly correlated with atrophy grades (r = 0.599, 0.751, respectively). It was observed that there was a statistically significant difference between the 1st (0-1 month) and 2nd (1-3 months) groups (p = 0.003, 0.001, respectively), and between the 2nd and 3rd (3-6 months) groups (p = 0.032, 0.002, respectively), but there was no significant difference between the 3rd and 4th (6-12 months) groups (p = 0.118, 0.057, respectively). In addition, there was a moderate correlation between tendon retraction and atrophy grades (r = 0.668). Power (1- b) in post hoc analysis was calculated as 0.826.

CONCLUSIONS

The current study, supported by arthroscopy, showed that there is a moderate and strong positive correlation between the time elapsed after trauma and the level of retraction and degree of atrophy in traumatic full-thickness SS tears, and demonstrated the importance of early surgical intervention in young patients.

Novel methods to diagnose rotator cuff tear and predict post-operative Re-tear: Radiomics models

Objective

To validated a classifier to distinguish the status of rotator cuff tear and predict post-operative re-tear by utilizing magnetic resonance imaging (MRI) markers.

Methods

This retrospective study included patients with healthy rotator cuff and patients diagnosed as rotator cuff tear (RCT) by MRI. Radiomics features were identified from the pre-operative shoulder MRI and selected by using maximum relevance minimum redundancy (MRMR) methods. A radiomics model for diagnosis of RCT was constructed, based on the 3D volume of interest (VOI) of supraspinatus. Another model for the prediction of rotator re-tear after rotator cuff repair (Re-RCT) was constructed based on VOI of humerus, supraspinatus, infraspinatus and other clinical parameters.

Results

The model for diagnosing the status of RCT produced an area under the receiver operating characteristic curve (AUC) of 0.989 in the training cohort and 0.979 for the validation cohort. The radiomics model for predicting Re-RCT produced an AUC of 0.923 ± 0.017 for the training dataset and 0.790 ± 0.082 for the validation dataset. The nomogram combining radiomics features and clinical factors yielded an AUC of 0.961 ± 0.020 for the training dataset and 0.808 ± 0.081 for the validation dataset, which displayed the best performance among all models.

Conclusion

Radiomics models for the diagnosis of rotator cuff tear and prediction of post-operative Re-RCT yielded a decent prediction accuracy.

Anatomic restoration of the articular deep layer is a definitive factor for repair status in delaminated rotator cuff tear

BACKGROUND

Recent studies have focused on the deep layer in delaminated rotator cuff tears. However, no studies have discussed the relationship between repair success and the properties of the deep layer. Herein, we aimed to analyze the intraoperative repair tension of the deep layer with respect to clinical outcomes and repair integrity and to evaluate the clinical results of delaminated rotator cuff tears after dual layer-specific repair.

METHODS

A total of 202 patients with delaminated rotator cuff tears had undergone dual layer-specific suture bridge repair; the mean follow-up duration was 28.6 (24-72) months. Intraoperatively, the repair tension of the deep layer was measured using a tensiometer, and mobility was ranked as easy or tight. After repair of the deep layer, the superficial layer tension was measured and ranked in a similar fashion. Clinical outcomes were evaluated using the Constant score, American Shoulder and Elbow Surgeons score, and subjective shoulder values. The relationship between retear and intraoperative qualitative factors of tendons was investigated. Prognostic factors for retear were analyzed using multiple logistic regression analyses.

RESULTS

Postoperative retears occurred in 11 (5.4%) patients. With regard to the deep layer, the tight mobility group had greater tear size, tendon retraction, and fatty infiltration of the supraspinatus and infraspinatus than the easy mobility group. No intergroup difference in postoperative retear rate was observed between the tight and easy deep-layer groups. Logistic regression analysis showed that fatty infiltration of the infraspinatus (odds ratio, 3.1; 95% confidence interval, 1.3-7.7; P = .013) and mobility of the superficial layer after deep layer repair (odds ratio, 8.1; 95% confidence interval, 1.7-38.1; P = .008) were predictors of retear.

CONCLUSION

Intraoperative mobility in the deep layer was not directly related to postoperative retear. Conversely, the quality of the infraspinatus concomitant with mobility of the superficial layer after deep layer repair significantly influenced repair integrity. Good clinical results were obtained even in cases with high repair tension of the deep layer.

Delaminated Tears of the Rotator Cuff: MRI Interpretation with Clinical Correlation

(1) Background: A delaminated tear is described as a horizontal split in the tendon substance. This review summarizes the clinical and radiologic characteristics of delaminated tears of the rotator cuff. (2) Methods: Initial radiological characteristics of a delaminated tear include the horizontal component of a partial-thickness tear determined using magnetic resonance (MR) arthrography. As demonstrated using indirect MR arthrography, the tear gradually progresses to be defined as either horizontal intrasubstantial splitting of the bursal and articular layers or differential retraction of the bursal and articular layers. (3) Results: The existence of delaminated tears is a poor prognostic factor in functional and morphologic outcomes after the repair of rotator cuff tendons and many surgical techniques have been introduced to solve this problem. Although the presence of a delaminated tear does not affect the arthroscopic repair outcome, the presence of medium-to-large, retracted delaminated tears may be an adverse negative prognostic factor after single-row repair. (4) Conclusion: Advances in imaging and surgical techniques have improved the detection of delaminated rotator cuff tears. Preoperative identification of delaminated tears on magnetic resonance imaging is clinically important because tailored surgical repair techniques must be chosen for successful outcomes.

"Triple Package" Modified SpeedBridge Rotator Cuff Repair Technique

Treatment of full-thickness rotator cuff repairs vary in surgical technique depending on many factors including tear geometry, delamination of soft tissue, tissue quality, and rotator cuff retraction. The described technique presents a reproducible method of addressing tear patterns where the tear may be larger laterally, but the medial footprint exposure is small. This can be addressed with a single medial anchor combined with a knotless lateral-row technique to provide compression for small tears or two medial row anchors for moderate to large tears. In this modification of the standard knotless double row (SpeedBridge) technique, 2 medial row anchors are used, with 1 augmented with additional fiber tape and an additional lateral row anchor to create a triangular repair construct, increasing the size and stability of the footprint of the lateral row.

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.

Rotator Cuff Delamination Is Associated With Increased Tendon Retraction and Higher Fatty Muscle Infiltration: A Comparative Study on Arthroscopy and Magnetic Resonance Imaging

PURPOSE

To investigate (1) tendon delamination according to different rotator cuff tear patterns as well as (2) the association of tendon retraction and fatty muscle infiltration with delamination of the rotator cuff. Furthermore, we aimed to establish the accuracy of magnetic resonance imaging for the detection of rotator cuff delamination.

METHODS

Magnetic resonance imaging scans of patients who underwent arthroscopic rotator cuff repair from 2013 to 2015 were retrospectively compared to intraoperative findings. Prevalences of tendon delamination, tendon retraction, and fatty muscle infiltration were categorized according to different rotator cuff tear patterns. For comparability of the amount of tendon retraction of delaminated and non-delaminated rotator cuff tears, we introduced the global retraction index, a description individually assessing tendon retraction in magnetic resonance imaging scans of all visible layers.

RESULTS

Of 349 shoulders, tendon delamination was observed in 231 patients (66.2%). Of these, rotator cuff delamination was most commonly seen in posterosuperior rotator cuff tears (84.6%). Delaminated rotator cuff tears presented with a significantly higher global retraction index (P < .001) as well as higher fatty muscle infiltration of the supraspinatus (P = .001) and infraspinatus (P = .001). Magnetic resonance imaging had only moderate accuracy (57.3%) to detect rotator cuff delamination, with a positive predictive value of 100% (95% confidence interval [CI] 95.6% to 100.0%) and a negative predictive value of 44.2% (95% CI 38.1% to 50.4%).

CONCLUSIONS

Tendon delamination was most commonly observed in posterosuperior rotator cuff tears. Delaminated rotator cuff tears showed a significantly greater tendon retraction as well as a higher amount of fatty muscle infiltration of the supraspinatus and infraspinatus. Magnetic resonance imaging has only moderate accuracy for detection of rotator cuff delamination.

LEVEL OF EVIDENCE

III, retrospective cohort study.

[Research progress of indication and treatment of graft in shoulder superior capsular reconstruction for rotator cuff tear]

Objective

To review the research progress of indication and treatment of graft in shoulder superior capsular reconstruction (SCR) for rotator cuff tear (RCT).

Methods

The literature related to shoulder SCR in recent years was extensively reviewed, and the anatomy, biomechanics, surgical indications, and treatment of graft in SCR were summarized.

Results

Superior capsule plays a role as a functional complex with rotator cuff, ligament, and whole capsule. SCR can effectively restore the superior stability of the shoulder. The indications of SCR include the irreparable massive RCT, massive RCT combined with pseudoparalysis shoulder, medium/large RCT with severe degenerative rotator cuff tissue, and dual-layer RCT. In order to achieve a better healing of tendon-bone in graft and decrease the rate of long-term graft retearing, it is essential to select an appropriate thickness graft, fix the graft in right intensity, and get a better capsular continuity.

Conclusion

The technique of SCR advanced to SCR for reinforcement and it is indicated from substantial massive RCT to severe degeneration of rotator cuff tissue. Graft treatment is the key step for a successful SCR.

Separate double-layer repair versus en masse repair for delaminated rotator cuff tears: a systematic review and meta-analysis

OBJECTIVE

Delaminated rotator cuff tears are a common shoulder disorder in elderly individuals. Either arthroscopic separate double-layer repair (DR) or en masse repair (ER) is used to treat a delaminated rotator cuff tear. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic ER versus DR intervention.

METHODS

Five studies were acquired from PubMed, Medline, Embase, CNKI, Google, and the Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed with RevMan 5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. The Cochrane Collaboration's risk of bias tool and Newcastle-Ottawa Scale were used to assess the risk of bias.

RESULTS

Five studies, including two randomized controlled trials (RCTs) and three observational studies, were assessed. The methodological quality of the trials ranged from low to high. The pooled results for the Shoulder Rating Scale of the University of California at Los Angeles (UCLA) score, visual analog scale (VAS) score, Constant score, and range of motion (ROM) showed that the outcomes were not statistically significant between the two interventions. The difference in retear rate was not statistically significant (OR = 0.69, 95% CI = 0.36-1.33, P = 0.27). The sensitivity analysis proved the stability of the pooled results, and publication bias was not apparent.

CONCLUSIONS

Both arthroscopic ER and DR interventions had benefits in delaminated rotator cuff tear treatment. ER and DR treatments were equally effective and had the same retear rate. The arthroscopic DR technique could not be recommended as the optical choice for delaminated rotator cuff tears based on current evidence.

Glossary of terms for musculoskeletal radiology

Members of the International Skeletal Society compiled a glossary of terms for musculoskeletal radiology. The authors also represent national radiology or pathology societies in Asia, Australia, Europe, and the USA. We provide brief descriptions of musculoskeletal structures, disease processes, and syndromes and address their imaging features. Given the abundance of musculoskeletal disorders and derangements, we chose to omit most terms relating to neoplasm, spine, intervention, and pediatrics. Consensus agreement was obtained from 19 musculoskeletal radiology societies worldwide.

A Modified SpeedBridge Technique for Retracted or Delaminated Rotator Cuff Repairs

Treatment of full-thickness rotator cuff tears vary in surgical technique dependent on the amount of retraction of the rotator cuff and/or delamination of the soft tissue. The described technique addresses both of those concerns. We present a modification of the SpeedBridge technique used to address retracted or delaminated repairs and effectively expand the indications for use of the double-row knotless technique. In this modification, the reduction is performed by an initial anchor with several stay sutures providing provisional reduction of the tissue in a controlled fashion. This is followed by compression through a standard double-row technique.

Delaminated Rotator Cuff Tear: Concurrent Concept and Treatment

Delaminated rotator cuff tear pertains to the horizontal split of the tendon substance. As reported previously, the presence of a delaminated tear and incidence of delaminated rotator cuff tear ranges from 38% to 92%. The different strain intensities applied across the rotator cuff tendon, and the shear stress between the bursal and articular layers seem to play a role in its pathogenesis. In a delaminated rotator cuff tear, the degree and direction of retraction between two layers differ, with accompanying intrasubstance cleavage. A surgeon therefore needs to consider and carefully evaluate the tear characteristics when repairing delaminated rotator cuff tear. Delaminated rotator cuff tear is considered to be a poor prognostic factor after rotator cuff repair, but numerous surgical repair techniques have been introduced and applied to resolve this problem. Recent literature has reported good clinical outcomes after delaminated rotator cuff repair.