Laminated tears of the human rotator cuff: a histologic and immunochemical study

A Modified Arthroscopic Triple-row Repair Technique for L-shaped Delaminated Rotator Cuff Tears

OBJECTIVE

To compare the clinical outcomes of a modified arthroscopic triple-row (TR) repair technique with the suture bridge (SB) repair technique in treating L-shaped delaminated rotator cuff tears. Various surgical techniques for L-shaped delaminated rotator cuff tears have been reported, many of which aid in increasing the contact area and pressure of the rotator cuff. However, there is still debate over which technique yields superior results.

METHODS

From January 2017 to March 2020, 61 cases of L-shaped delaminated rotator cuff tears were included in this study. Of these, 34 cases underwent the modified arthroscopic triple-row repair technique, while 27 cases were addressed with the suture bridge repair technique. Functional assessment was conducted using the American Shoulder and Elbow Surgeons (ASES) score, the University of California Los Angeles (UCLA) shoulder score, the Constant score (CS), and the visual analogue scale (VAS) score. Magnetic Resonance Imaging (MRI) assessments for rotator cuff healing were performed at the 24-month postoperative mark. Statistical evaluations were conducted using SPSS for Windows (Version 25.0, IBM, Armonk, NY, USA), employing the Wilcoxon signed-rank test to compare preoperative and postoperative data and ROM differences, and the Mann-Whitney U test for statistical differences in clinical outcome scores between the two groups. A p-value of less than 0.05 was considered statistically significant.

RESULTS

Comparative analysis of the preoperative and final follow-up scores revealed a substantial enhancement in shoulder function, as indicated by the ASES, UCLA, CS, and VAS scores, with statistical significance (p < 0.001). At both the preoperative stage and final follow-up, no notable differences were observed in ASES, UCLA, CS, and VAS scores between the two groups. However, the TR repair group exhibited lower VAS scores than the SB group at 1 and 3 months postoperatively. Active range of motion (ROM) showed significant improvement in both groups. No significant differences in ROM were noted between the two groups either before the surgery or at the final follow-up.

CONCLUSION

The study demonstrates that both the modified arthroscopic TR and SB techniques for L-shaped delaminated cuff tears yield satisfactory outcomes, with no significant differences in overall clinical performance. Notably, early postoperative pain management appears more effective with the modified TR technique, suggesting its potential for enhanced early recovery experiences. This technique's design, promoting securer fixation and optimal contact conditions, is implied to facilitate superior long-term healing, warranting further investigation into its long-term benefits.

Anterior capsular reconstruction in irreparable subscapularis tear: human dermal allograft

BACKGROUND

The irreparable subscapularis (SSc) tears pose an extremely difficult situation to manage, especially in the younger population. The anterior capsular reconstruction (ACR) with human dermal allograft (HDA) is an alternative to tendon transfer with sound biomechanical advantages and clinical outcomes. The purpose of this study was to evaluate the early clinical and radiologic outcomes of open ACR with HDA in patients with irreparable SSc tears.

METHODS

Eighteen patients who had an open ACR with HDA for irreparable SSc tears between August 2020 and January 2022 were enrolled. There were 11 male and 7 female patients with a mean age of 63.7 years and a mean follow-up of 17 months (range, 12-28 months). The dominant side was affected in 10 patients. One of the 18 patients had reconstruction with single-layer HDA, 14 had double-layer HDA, and 3 had SSc augmentation over double-layer HDA. Clinical and radiologic outcomes were assessed and compared pre- and postoperatively.

RESULTS

There was significant improvement in visual analog scale score from 6.6 ± 1.6 to 1.6 ± 1.5 (P < .001) and in the total University of California-Los Angeles shoulder score from 12.4 ± 4.3 to 29.0 ± 4.5 (P < .001). Forward flexion, abduction, and internal rotation (IR) increased by 28.6°, 32.5°, and 11.8°, respectively (P < .001). External rotation decreased by 6.4° (P = .020). There was notable improvement in IR strength (percentage of that of the opposite, normal side) from 66.0% ± 19.4% to 84.4% ± 22.3% (P = .008). The mean postoperative coracohumeral distance improved from 3.0 to 6.0 mm (P < .001), the anterior translation of the humeral head reduced from 1.5 to 0.5 mm (P = .210), and the acromiohumeral interval from 8.1 to 8.8 mm (P = .070). The patients' satisfaction at final follow-up was rated 4.1 of 5.0 (P < .001). Sixteen of 18 patients (88.9%) had the HDA healed at the glenoid and humeral side, and 2 (11.1%) had retear at the final follow-up. Among the 17 who had double-layer HDA, none showed any healing between the layers.

CONCLUSION

This study showed that early significant and comprehensive improvement inclusive of pain relief, improvement in range of motion, IR strength, and reduction of anterosuperior translation was achievable by open ACR with HDA for irreparable SSc tear.

Outcomes After Double-Layer Repair Versus En Masse Repair for Delaminated Rotator Cuff Injury: A Systematic Review and Meta-analysis

Background

Delamination of rotator cuff tears during arthroscopic shoulder surgery has an incidence of 38% to 92%. Double-layer (DL) repair and en masse (EM) repair are most commonly used in this situation.

Purpose

To compare the clinical results of the DL versus EM repair techniques for delaminated rotator cuff tears using a meta-analysis.

Study Design

Systematic review; level of evidence, 3.

Methods

We identified relevant studies comparing the clinical results of DL and EM repair for delaminated rotator cuff injuries in the PubMed, Embase, and Cochrane databases after the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The primary outcomes were the Constant score and retear rate. Additionally, we compared other postoperative shoulder functional scores, shoulder range of motion, and visual analog scale (VAS) pain scores between the 2 suture methods using a meta-analysis. The mean difference (MD) was compared for continuous outcomes, and the odds ratios (ORs) were compared for categorical outcomes.

Results

Of the 197 studies initially identified, 6 studies were included in this analysis. There were significant differences in the Constant score (MD, 8.64 [95% CI, 4.47 to 12.8]; P < .05) and external rotation (MD, 5.10 [95% CI, 2.63 to 7.56]; P < .05) between the 2 techniques, with DL repair having superior outcomes. No significant differences were observed between the 2 techniques in forward flexion (MD, 0.62 [95% CI, -1.18 to 2.43]; P = .50), VAS pain (MD, -0.03 [95% CI, -0.34 to 0.27]; P = .84), or retear rate (OR, 0.73 [95% CI, 0.37 to 1.41]; P = .35).

Conclusion

Results of this review and meta-analysis suggest that DL repair was more beneficial than EM repair in terms of the Constant score and shoulder external rotation in patients with delaminated rotator cuff injuries.

Comparison of Outcomes After Arthroscopic Superior Capsule Reconstruction Versus Arthroscopic Partial Repair or Arthroscopic Debridement for Irreparable Rotator Cuff Tears

Background

Arthroscopic superior capsule reconstruction (SCR), arthroscopic partial repair (PR), and arthroscopic debridement (DB) are valid treatment options for irreparable rotator cuff (RC) tears.

Purpose/Hypothesis

The purpose of this study was to compare clinical, functional, and radiological outcomes of arthroscopic SCR with arthroscopic PR and arthroscopic DB in patients with irreparable posterosuperior RC tears. It was hypothesized that SCR would lead to superior clinical and functional outcomes compared with PR or DB.

Study Design

Cohort study; Level of evidence, 3.

Methods

Clinical and functional outcomes of this single-center retrospective study included range of motion, strength, and the age- and sex-adjusted Constant-Murley score. Patient-reported outcome measures (PROMs) involved the quick Disabilities of the Arm, Shoulder and Hand score, the Subjective Shoulder Value, and the visual analog scale for pain. Graft and repaired tendon integrity was evaluated by magnetic resonance imaging (MRI) at 12 months of follow-up.

Results

In total, 57 patients treated with SCR (n = 20), PR (n = 17), and DB (n = 20) were included. The mean clinical follow-up was 33.8 ± 17.9 months. Preoperative clinical and functional characteristics were comparable among the 3 groups. The range of motion and clinical and functional scores of all 3 groups significantly improved from pre- to postoperatively. Postoperative PROMs showed no differences among all 3 study groups. SCR revealed significantly higher postoperative strength compared with PR (P = .001) and DB (P = .004). Postoperative MRI revealed a rerupture in 4 patients with SCR (20%). Postoperative MRI showed a rerupture in 9 patients with PR ( 53%). Fatty muscle infiltration of the supraspinatus and infraspinatus significantly progressed within all 3 study groups in postoperative MRI scans. No clinical and functional differences were observed between intact and reruptured PR.

Conclusion

Patients who underwent SCR had better postoperative strength recovery than patients who underwent PR or DB.

Delamination of rotator cuff tears: Real-time dynamic ultrasound findings

PURPOSE

The purpose of this study was to evaluate the value of diagnosing delaminated tears and ultrasonic characteristics on real-time dynamic ultrasound.

MATERIALS AND METHODS

We enrolled 143 consecutive patients who underwent arthroscopic rotator cuff repair between April 2020 and January 2021. All patients were examined using real-time dynamic ultrasound of the shoulder within 2 weeks before arthroscopy. In our study, delaminated tears were defined as intratendinous horizontal splitting with or without the retraction of the articular or bursal layer of tendon. Delaminated tears were classified into three types on the basis of their shape: greater retraction of the articular layer (type I), greater retraction of the bursal layer (type II), and equal retraction of both layers (type III). The sensitivity and specificity of real-time dynamic ultrasound for evaluation of delaminated tears were calculated using arthroscopy findings as the gold standard. Ultrasonic imaging appearances of delaminated rotator cuff tears were further described.

RESULTS

Of the 143 patients, 47 (32.9%) had delaminated tears as confirmed by arthroscopy; 35 of these tears involved the supraspinatus tendon and 12 involved both supraspinatus and infraspinatus tendons. Real-time dynamic ultrasound correctly diagnosed 36 of 47 delaminated tears with sensitivity 72.0% (57.2%-83.3%) and specificity 96.7% (90.2%-99.2%). Moreover, type I tear (n = 32) was more common than type II (n = 11) and type III tears (n = 4). Real-time dynamic ultrasound evaluated shape of type I, type II, and type III with a sensitivity and specificity of 56% and 80%, 72% and 83%, and 100% and 98%, respectively. Anechoic horizontal linear splitting of tendon, unequal retraction of the bursal and articular layers, and thinning of the suffering tendon were the three signs observed during real-time dynamic ultrasound examination. These three signs were indicative of a diagnosis of delaminated rotator cuff tears with high specificities (100.0%, 100.0%, and 97.9%, respectively) but relatively low sensitivities (25.5%, 25.5%, and 36.2%, respectively).

CONCLUSION

Real-time dynamic ultrasound can be practically used for diagnosing delamination of rotator cuff tears with medium sensitivity and high specificity. Anechoic horizontal linear splitting of tendon, unequal retraction of the bursal and articular layers, and thinning of the involved tendon are the three important ultrasonic signs for diagnosis of delaminated rotator cuff tears.

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.

A Propensity Score-Matched Comparison Between Knotless Layer-by-Layer and En Masse Suture Bridge Techniques for Delaminated Rotator Cuff Tears

BACKGROUND

Because the articular layer is more prone to retraction than the bursal layer of the supraspinatus tendon, it is important to restore each layer anatomically while repairing delaminated rotator cuff tears (RCTs).

PURPOSE

To compare clinical outcomes and tendon integrity between knotless layer-by-layer and conventional en masse repair techniques for delaminated RCTs.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

We retrospectively reviewed data from 174 consecutive patients with delaminated RCTs treated by arthroscopic suture bridge repair. Only 115 patients with medium to large supraspinatus tears with delamination were included. The 33 patients treated using the knotless layer-by-layer technique (group 2) were matched 1:1 with patients treated using en masse repair with the suture bridge technique (group 1) based on propensity scores. Tendon thickness was measured on magnetic resonance imaging (MRI). Signal changes in the bursal, articular, and intratendinous layers were assessed using T2-weighted MRI.

RESULTS

Postoperatively, statistically significant improvements were seen in both groups compared with preoperatively functional scores. At the final follow-up, there was a statistically significant difference in the Constant score, which was higher in group 2 than in group 1 (91.4 ± 6.0 and 84.3 ± 16.4, respectively; P = .005). There was 1 case of a retear in each group, representing a 3% retear rate. Group 2 had thicker tendons than group 1 (6.9 ± 1.1 and 6.0 ± 1.2 mm, respectively; P = .017). On T2-weighted MRI, a low signal intensity in the articular layer was more common in group 2 (P = .046).

CONCLUSION

En masse repair using the suture bridge technique and the knotless layer-by-layer technique were both effective. Regarding tendon healing, no significant differences were seen in retear rates. However, superior results in terms of the Constant score, tendon thickness, and signal intensity in the articular layer were observed using the knotless layer-by-layer technique.

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.

Delamination in rotator cuff tears: Explanation of etiology through anatomical dissection

The prognostic significance of delaminated rotator cuff tears remains controversial. However, as the surgical goal is to maximize the contact area between layers, the macroscopic appearance of partial delaminated rotator cuff tears is essential. The aim of this anatomical study was to investigate the morphology of delaminated rotator cuff tears. We hypothesized that delamination zones at the intersection of the supraspinatus and infraspinatus tendon fibers are the origin of articular-side degenerative rotator cuff tears. Forty anatomical specimens were evaluated in this study. The supraspinatus and infraspinatus muscles were dissected, the origins were meticulously worked out and followed to their insertions at the humeral head. Fiber exchanges, overlays and delamination zones between the supraspinatus and infraspinatus muscles were photographically documented and measured. Delamination of rotator cuff tears can be classified into articular-side and bursal-side tears. The articular-layer consists of capsuloligamentous tissue, which included the rotator-cable/rotator-crescent complex, the joint capsule and a small part of the supraspinatus tendon. The bursal-side layer represents the tendinous tissue, which consists of the parallel, tendinous parts of the supraspinatus and infraspinatus muscles. Delamination of rotator cuff tears can be classified into articular-side and bursal-side tears. Present model of degenerative tears might explain the high prevalence of articular-side tears, which expand into the rotator-cable/rotator-crescent complex. It may be important for surgeons to incorporate these anatomical findings and considerations into the surgical planning.

Comparison of three suture-bridge techniques for large or massive rotator cuff tear with delamination

Introduction: Rotator cuff tear with delamination is considered a risk factor for postoperative retear. The purpose of this study was to compare clinical outcomes between three repair procedures for large or massive rotator cuff tears with delamination: conventional en masse suture bridge (EMSB), double-layer suture bridge (DLSB), and the combination of DLSB with modified Debyere-Patte (DLSB + DP). Methods: 53 shoulders of 52 patients who had massive rotator cuff tears with delamination were categorized into three groups: EMSB (18 shoulders), DLSB (24 shoulders), and DLSB + DP (11 shoulders). The mean postoperative follow-up period was 34.6 months. Pre- and postoperative evaluations included a range of motion (ROM), Constant scores, global fatty degeneration (GFDI), and tendon integrity according to Sugaya’s classification by magnetic resonance images (MRI). Results: In all groups, ROM significantly improved after the procedures. Mean constant scores significantly improved: from 45.5 to 77.4 after EMSB, from 45.5 to 87.6 after DLSB, and from 46.3 to 88.0 after DLSB + DP. Significant differences were noted in postoperative Constant scores (p = 0.018: DLSB vs. EMSB, and p = 0.045: DLSB + DP vs. EMSB). The Constant pain scores were better for DLSB + DP than for EMSB (p = 0.012). Global fatty degeneration index (GFDI) with DLSB + DP was significantly higher than that for either EMSB or DLSB, indicating significant preoperative fatty degeneration for DLSB + DP. Retear occurred in 27.8% of the EMSB group, 12.5% of the DLSB group, and 9.1% of the DLSB + DP group. Discussion: Comparisons of the three groups demonstrated that DLSB and DLSB + DP achieved better clinical outcomes than EMSB for the repair of large or massive rotator cuff tears. DLSB + DP is useful for massive rotator cuff tears with severe fatty degeneration or for cases where the presence of excessive tension is anticipated when repairing the torn cuff.

Surgical Treatment Outcomes for Everted Bursal Flap of Delaminated Supraspinatus Tear

Background:

Although everted bursal flaps of delaminated tears have been reported, few studies have reported radiologic images, arthroscopic findings, and clinical results after repair.

Purpose:

To compare the repair outcomes of everted delaminated tears with those of classic delaminated supraspinatus tears.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Among 153 patients who underwent arthroscopic rotator cuff repair for a delaminated supraspinatus tear, everted bursal flap tears were observed in 24 patients upon arthroscopy (group A). Another 24 patients with classic delaminated supraspinatus tears, matched for age and sex, were selected for group B. Magnetic resonance imaging (MRI) and ultrasonography were performed preoperatively and postoperatively. Patients were evaluated using a visual analog scale (VAS) for pain as well as functional scores (American Shoulder and Elbow Surgeons [ASES] score, Constant score, and University of California Los Angeles shoulder score). Scores were compared preoperatively and at final follow-up (mean follow-up, 32 months).

Results:

Patients in both groups A and B reported improved VAS and functional scores at the final follow-up. In group A, preoperative VAS scores were higher and functional scores were poorer than in group B. Subacromial effusions with tendon swelling on preoperative MRI were more common in group A. During follow-up ultrasonography, group A patients exhibited persistent subacromial effusion. However, VAS scores at final follow-up were significantly better in group A (0.4 ± 0.7) than in group B (1.6 ± 1.4) (P < .001), and ASES scores at final follow-up were better in group A (84.3 ± 4.3) than in group B (77.0 ± 10.2) (P = .005).

Conclusion:

Everted bursal flap delaminated tears were associated with higher VAS scores and poorer functional scores preoperatively. Although subacromial effusions were experienced by group A during the early postoperative period, clinical outcomes at final follow-up were significantly better for everted delaminated tears compared with classic delaminated tears.

Lateral acromioplasty cannot sufficiently reduce the critical shoulder angle if preoperatively measured over 40°

PURPOSE

To investigate whether arthroscopic lateral acromion resection can sufficiently reduce the critical shoulder angle (CSA) without damaging deltoid muscle insertion.

METHODS

Ninety patients who underwent arthroscopic rotator cuff (RC) repair were retrospectively analysed. According to the preoperative CSA, patients were categorized as Group I (CSA < 35°) and Group II (CSA ≥ 35°). Additional arthroscopic lateral acromion resection was performed in Group II. The CSA was measured 1 week postoperatively, while RC integrity and the deltoid attachment were assessed at 3, 6 and 12 months via ultrasound. Deltoid function was evaluated using the Akimbo test, in which patients place their hands on the iliac crest with abduction in the coronal plane and internal rotation of the shoulder joint while simultaneously flexing the elbow joint and pronating the forearm.

RESULTS

Large and massive RC tears were more prevalent in Group II (p = 0.017). In both groups, the CSA reduction was statistically significant (Group I = 1°: range 0°-3°, Group II = 3.7°: range 1°-8°; p < 0.001). When the preoperative CSA was > 40°, the respective postoperative CSA remained > 35° in 83.3% of cases (p < 0.001). Final shoulder strength was correlated with the amount of CSA reduction (rho = 0.41, p = 0.002). The postoperative CSA was higher, but not significantly different (n.s.), in patients with re-torn (36°, range 32°-40°) than with healed RC (33°, range 26°-38°). No clinical detachment or hypotrophy of the deltoid was observed with the Akimbo test and ultrasound evaluation.

CONCLUSIONS

Arthroscopic lateral acromion resection is a safe procedure without affecting deltoid muscle origin or function, and it is effective in significantly reducing the CSA. However, the CSA cannot always be reduced to < 35°, especially in patients with preoperative CSA values > 40°.

LEVEL OF EVIDENCE

III.

Clinical and radiological outcomes of arthroscopic en bloc repair for delaminated rotator cuff tear versus non-delaminated tear

PURPOSE

The objective of the study is to determine clinical and radiological outcomes of arthroscopic repair for delaminated tears versus non-delaminated tears.

METHODS

Consecutive 138 patients with full-thickness rotator cuff tear were retrospectively enrolled. They were divided into two groups based on the presence of delamination. All delaminated tears were repaired by en bloc technique (suturing both layers by single stitch). Delaminated tears were categorized into two types: (1) posterior type, delamination involving mainly infraspinatus and (2) complete type, delamination involving both supraspinatus and infraspinatus. Clinical assessments were done using pain visual analog scale (PVAS), functional VAS, American Shoulder Elbow Surgeons score, the Constant score, and range of motion. Postoperative MRI was performed at 6 months after surgery to determine repair integrity.

RESULTS

Of the 138 patients, 78 (56.5%) had delaminated tears, including 30 cases of posterior type and 48 cases of complete type. The retear rate was 6.7% (4/60) in the non-delamination group and 5.1% (4/78) in the delamination group, showing no significant difference between the two groups. There was no significant difference in Sugaya classification between the two groups. Clinical scores were improved significantly in both delamination and non-delamination groups postoperatively, showing no significant difference between the two groups. Delamination subgroup (posterior or complete type) showed no significant correlation with retear rate, Sugaya classification, or clinical outcome.

CONCLUSIONS

Arthroscopic en bloc repair for delaminated rotator cuff tear showed no significant difference in clinical or radiological outcome from that for non-delaminated rotator cuff tear. The extent of delamination did not affect outcome either. Levels of Evidence: Level III, Retrospective comparative study.

Relation of Superficial and Deep Layers of Delaminated Rotator Cuff Tear to Supraspinatus and Infraspinatus Insertions

BACKGROUND

It remains unclear whether the deep layer of the rotator cuff is an articular layer of the supraspinatus (SS) or infraspinatus (IS), rotator cable, or superior capsule. Therefore, this study aimed to analyse the relationship between occupation ratios and delamination patterns of rotator cuff tears (RCTs). We hypothesised that the deep layers are related to the occupation ratios of the deep SS and IS sections.

MATERIALS AND METHODS

A total of 265 patients with RCTs were retrospectively enrolled between 2013 and 2017 and divided into four groups: A, non-delaminated tear; B, delaminated tear with the deep layer equally retracted to the superficial layer; C, delaminated tear with the deep layer more retracted; D, delaminated tear with the superficial layer more retracted. Muscle volume was evaluated by measurement of each occupation ratio of the SS and IS, and the IS muscle was additionally divided into two areas, deep and superficial.

RESULTS

The SS occupation ratio was significantly lower in group C than in the other groups (p = 0.009). Conversely, comparison of the IS occupation ratios revealed no significant intergroup differences. The occupation ratio of the superficial IS was significantly lower in group D than in the other groups (p = 0.003). In group C, the occupation ratios of the deep IS section were significantly decreased according to RCT size (p = 0.034).

CONCLUSION

Our findings demonstrate that the superficial layers are related to the IS superficial section and the deep layers to the SS and IS deep sections.

LEVEL OF STUDY

IV.

Restoration of supraspinatus and infraspinatus deep plane occupation ratios was greater in delaminated tears than in non-delaminated tears after rotator cuff repair

Total 132 patients who underwent arthroscopic suture bridge repair were divided into two groups: group A, non-delaminated tears; group B, deep layer, more retracted, delaminated tears. In addition, group B were divided into two subgroups: group I (≤2-cm) and group II (>2-cm). Muscle volume was evaluated by measuring the occupation ratio and restoration of the rotator cuff muscle was defined as the difference between the preoperative and postoperative occupation ratios. The restoration of the SS and IS deep plane occupation ratios was greater in >2-cm-sized delaminated tears than in ≤2-cm-sized delaminated and non-delaminated tears.

Arthroscopic Knotless Separate Layer Transosseous Equivalent Repair of Delaminated Rotator Cuff Tears

Delamination of rotator cuff tears presents a challenge for surgeons. Recognizing and repairing such a complex tear pattern often require innovative approaches to achieve an anatomic restoration of footprint. In this Technical Note, we described our preferred method that anatomically repairs both layers of delaminated rotator cuff tear separately in a knotless transosseous equivalent technique. Two sutures are placed to the articular layer in a cinch stitch configuration. Then, closed-loop end sutures are passed through both layers while keeping the closed-loop end at the working portal. The free ends of cinch stitches are loaded to anchors with a preloaded fiber tape loop, which is placed to the medial row while approximating the articular layer onto its footprint. Fiber tapes are then shuttled through both layers of tendon with the help of a previously placed closed-loop suture. Finally, the lateral row anchors are placed while fiber tapes are tensioned in a cross-bridge configuration. We believe that this technique may facilitate uneventful healing of delaminated rotator cuffs by providing the biomechanical properties of transosseous equivalent repair.

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.

Comparison of Structural Integrity and Functional Outcome Between Delaminated and Nondelaminated Rotator Cuff Tears After En Masse Arthroscopic Repair: A Retrospective Cohort Study With Propensity Score Matching

BACKGROUND

Arthroscopic repair of delaminated rotator cuff tears (RCTs) has shown poor prognoses. Despite the importance of delaminated tears, only a few studies have compared delaminated and nondelaminated tears.

PURPOSE

This study aimed to compare the clinical outcomes and structural integrity after en masse arthroscopic rotator cuff repair between delaminated and nondelaminated RCTs and to evaluate whether infraspinatus tendon involvement affects the prognosis for delaminated tears after arthroscopic cuff repair, through use of propensity score matching for precise comparison.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This study included 180 consecutive patients with medium- or large-sized RCTs who had an arthroscopic rotator cuff repair with a minimum 2-year follow-up, of whom 57 and 123 had delaminated tears (group 1) and nondelaminated tears (group 2), respectively. The en masse repair technique using a single-row or transosseous-equivalent double-row suture-bridge technique was used for of all the delaminated cases. Preoperative and postoperative visual analog scale pain scores, shoulder active range of motion, American Shoulder and Elbow Surgeons (ASES) scores, and Constant scores were assessed. Magnetic resonance imaging was performed at least 24 months postoperatively to identify retear of the repaired rotator cuffs. After propensity score matching, 32 cases in both groups were successfully matched, and the clinical and radiological results were analyzed.

RESULTS

Before propensity score matching, postoperative clinical outcomes were improved, showing no significant differences between the groups, excluding forward elevation ( P = .011). Groups 1 and 2 had 17 (29.8%) and 11 retear cases (8.9%), respectively ( P < .001). After propensity score matching, only the ASES score (72.5 vs 77.1) showed a significant superiority in group 2 ( P = .038). Propensity-matched groups 1 and 2 had 8 (25.0%) and 2 (6.3%) retear cases, respectively ( P = .034). No significant difference was found in structural integrity depending on whether the RCT included the infraspinatus tendon (IST). The odds ratio for retear of the delaminated tears, including IST, was 5.5 (95% confidence interval, 1.0-30.0, P = .038).

CONCLUSION

Delaminated RCT was a negative prognostic factor of structural integrity after repair and could affect the functional outcome. However, whether IST tear was involved had no effect on the prognosis after repair.

Clinical and Radiographic Outcomes After Arthroscopic Lamina-Specific Double-Row Repair of Large Delaminated Rotator Cuff Tears in Active Patients

Background:

The presence of delamination and a larger rotator cuff tear (RCT) size have been associated with poorer outcomes in rotator cuff repair. Therefore, we developed a new surgical procedure, arthroscopic lamina-specific double-row fixation (ALSDR), for the repair of large delaminated RCTs.

Purpose:

To investigate the clinical outcomes, magnetic resonance imaging findings, and satisfaction with several variables after ALSDR for large delaminated RCTs.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 30 active patients (mean age, 59.1 years) undergoing ALSDR were assessed by a numeric rating scale (NRS; 0-10) for pain, surgery, work, and exercise as well as American Shoulder and Elbow Surgeons (ASES), Constant, and Simple Shoulder Test (SST) scores at a mean of 65.9 months postoperatively. Rotator cuff integrity was determined by magnetic resonance imaging. The Spearman correlation coefficient (ρ) was used to determine the correlation between clinical and NRS scores.

Results:

Five patients (16.7%) had a retear. Each of the postoperative functional and NRS scores except the NRS work score was significantly better in the healed shoulders than in the shoulders with a retear (P < .001). The NRS pain score showed a significant negative correlation with ASES, Constant, and SST scores (ρ = −0.775, −0.668, and −0.742, respectively; P < .001 for all). The NRS surgery score had a positive correlation with Constant and SST scores (ρ = 0.393 [P = .032] and ρ = 0.456 [P = .011], respectively). The NRS work score had a positive correlation with ASES, Constant, and SST scores (ρ = 0.382 [P = .037], ρ = 0.386 [P = .035], and ρ = 0.414 [P = .023], respectively). The NRS exercise score had a positive correlation with ASES, Constant, and SST scores (ρ = 0.567 [P = .001], ρ = 0.511 [P = .004], and ρ = 0.639 [P < .001], respectively).

Conclusion:

Our results showed that there was a significant correlation between clinical and NRS scores. The results indicate that ALSDR can provide a high degree of functionality and can be a useful alternative treatment for active patients with large delaminated RCTs.

Greater tuberosity angle and critical shoulder angle according to the delamination patterns of rotator cuff tear

The purpose was to evaluate the relationship between GTA, CSA, and the delamination patterns of RCTs. This study included 315 patients with RCTs from 2014 to 2018, retrospectively. The subjects were divided into 5 groups: Group A, control group; Group B, non-delaminated tear; Group C, delaminated tear with equally retraction of articular and bursal layer; Group D, articular layer more retracted delaminated tear, and Group E, bursal layer more retracted delaminated tear. In conclusion, large GTA and CSA were associated with rotator cuff tears. However, there was no difference of GTA and CSA according to the delamination patterns.

The Effect of Tendon Delamination on Rotator Cuff Healing

BACKGROUND

While patient age, tear size, and muscle fatty infiltration are factors known to affect the rate of tendon healing after rotator cuff repair, the effect of tendon delamination is less known.

PURPOSE

To assess the effect of tendon delamination on rotator cuff healing after arthroscopic single-row (SR) repair.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Consecutive patients (N = 117) with chronic full-thickness rotator cuff tears underwent arthroscopic SR repair with the tension-band cuff repair. The mean ± SD age at the time of surgery was 60 ± 8 years. There were 25 small, 63 medium, and 29 large tears. Tendon delamination was assessed intraoperatively under arthroscopy with the arthroscope placed in the lateral portal. Patients were divided into 2 groups: those with nondelaminated (n = 80) and delaminated (n = 37) cuff tears. The 2 groups were comparable for age, sex, body mass index, preoperative pain, strength, and a Constant-Murley score. Repair integrity was evaluated with sonography (mean, 24 months after surgery; range, 6-62 months) and classified into 3 categories: type A, indicating complete, homogeneous, and thick coverage of the footprint; type B, partial coverage with a thin tendon; and type C, no coverage of the footprint.

RESULTS

The prevalence of tendon delamination observed under arthroscopy was 32% (37 of 117), which increased with tear size and retraction: from 15% in small tears to 32% in medium tears and 45% in large tears ( P = .028). Postoperatively, 83 patients had complete coverage of footprint (type A = 71%) and the cuff was considered healed, whereas 26 had partial coverage or a thin tendon (type B = 22%) and 8 had no coverage (type C = 7%). Overall, the rate of complete healing was 78% in nondelaminated cuff tears and 57% in the case of tendon delamination ( P = .029). In large retracted tears, the healing rate dropped from 81% in the absence of delamination to 39% when the tendons were delaminated ( P = .027).

CONCLUSION

Tendon delamination increases with tear size and retraction. Patients with chronic delaminated and retracted rotator cuff tears (stage 2 or 3) are at risk of failure after SR cuff repair, whereas patients with small delaminated rotator cuff tears (stage 1) involving only the supraspinatus can be treated with an SR cuff repair with a high chance of tendon healing. These results suggest that SR cuff repair may be insufficient to treat delaminated chronic cuff tears. To improve the anatomic outcomes of rotator cuff repairs, surgeons should consider treating delaminated tears with a double-row or double-layer repair.

Factors associated with needle breakage of antegrade suture passer and effect of intratendinous remnant needle tip on clinical outcomes after arthroscopic rotator cuff repair

Objective

The aim of this study was to evaluate factors associated with the needle breakage of antegrade suture passer and the effect of intratendinous remnant needle tip on clinical outcomes after rotator cuff repair.

Methods

We retrospectively reviewed 283 patients (138 men and 145 women; mean age: 59.7 ± 9.3 years) who underwent arthroscopic repair for full-thickness rotator cuff tear. We evaluated the characteristics of 16 patients in whose needle tip had been broken and embedded and remained in the rotator cuff (remnant needle group) and compared them with the remaining 267 patients (control group). Afterwards, another 64 patients were selected from control group (1:4 matching) after propensity score matching (PSM). The groups were compared anatomically with MRI or ultrasonography and functionally (serial pain VAS and ROM; ASES, Constant, UCLA and SST scores) at a minimum follow-up of 1 year.

Results

The remnant needle group showed preoperative thicker tendon (6.72 mm vs 5.33 mm, p = 0.047), higher tendinosis (mean grade, 1.88 vs. 1.43, p = 0.029), and more frequent delaminated tears (p = 0.035) compared with control group. When we compare the clinical outcomes after PSM, the initial pain VAS of the remnant needle tip group was higher up to 3 months (pain VAS: 4.13 ± 2.07 vs 2.48 ± 1.61 (p = 0.032) at 5 weeks and 3.79 ± 2.12 vs 2.25 ± 1.76 (p = 0.044) at 3 months), however the difference disappeared after 6 months postoperatively. In final evaluation, there was no significant differences in every outcome parameters (all p > 0.05).

Conclusion

Breakage of the needle of the antegrade suture passer occurred more frequently in the thicker tendon, higher tendinosis, and delaminated tears. The retained broken needle tip was associated with higher pain scores during the early postoperative period, but revealed no difference in final outcomes by using PSM.

Level of Evidence

Level III, Therapeutic Study

Delamination Does Not Affect Outcomes After Arthroscopic Rotator Cuff Repair as Compared With Nondelaminated Rotator Cuff Tears: A Study of 1043 Consecutive Cases

BACKGROUND

Limited information is available regarding the characteristics of delaminated rotator cuff tears as compared with nondelaminated tears. Furthermore, there is conflicting information regarding the effects of delamination on the anatomic healing of repaired cuffs.

PURPOSE

To evaluate the characteristics and anatomic outcomes of delaminated rotator cuff tears in comparison with nondelaminated tears to determine whether delamination is a negative prognostic factor affecting rotator cuff repair outcomes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between 2010 and 2014, 1043 patients were enrolled in the study to assess the prevalence of delamination. Among them, the findings from 531 patients who underwent magnetic resonance imaging or computed tomographic arthrography at least 1 year after surgery were included to determine whether delamination was a negative prognostic factor affecting the anatomic outcomes of arthroscopic rotator cuff repair. Delamination was assessed intraoperatively and defined by distinguishable edge cleavage tearing or interstitial horizontal gap between the articular and bursal surfaces of the torn tendon. One of 3 repair techniques (modified Mason Allen, single row, or double row) was used according to tear configuration and tendon mobilization. The authors evaluated visual analog scale scores for pain and satisfaction and American Shoulder and Elbow Surgeons scores to quantify clinical outcomes.

RESULTS

The incidence of delamination was 42.9% (447 of 1043). As compared with those with nondelaminated tears, patients with delaminated tears were older ( P < .001) and had longer symptom duration ( P = .019), larger tear sizes and retractions ( P < .001 for both), higher grades of fatty infiltration of the rotator cuff muscles (all P < .001), and poorer tendon quality ( P < .001). The overall healing failure rate was 19.0% (101 of 531). In univariate analysis, the rate of healing failure for the repaired cuffs was significantly higher in the delaminated group (delaminated tears, 60 of 238, 25.2%; nondelaminated tears, 41 of 293, 14.0%; P = .001). However, results of subgroup and multivariate analyses showed that the presence of delamination was ultimately not an independent risk factor for the failure of cuff healing. Between the delaminated and nondelaminated groups, there was no significant difference in postoperative functional outcomes.

CONCLUSION

The results suggest that delaminated rotator cuff tears might represent chronic degenerative tears of longer symptom duration, with larger tear sizes and higher grades of fatty infiltration in older patients. It appears that delamination could be a confounding factor, not an independent prognostic factor, affecting rotator cuff healing.

Morphologic Factors Related to Repair Outcomes for Delaminated Rotator Cuff Tears: A Minimum 2-Year Retrospective Comparison Study

PURPOSE

To evaluate clinical outcomes and repair integrity after en masse transosseous-equivalent suture bridge repair for delaminated rotator cuff tears and to analyze the morphologic factors related to clinical outcomes and repair integrity.

METHODS

This study included 99 patients who underwent the technique of en masse transosseous-equivalent suture bridge repair for delaminated rotator cuff tears. Morphologic factors were estimated using magnetic resonance imaging, and clinical outcomes were evaluated using the University of California, Los Angeles score; American Shoulder and Elbow Surgeons score; and Constant shoulder score. The morphologic factors included the shape of delamination, retraction length of the bursal and articular layers, gap distance between the layers, and length of the intrasubstance cleavage. According to follow-up magnetic resonance imaging, cases were categorized into the intact or retear group. The morphologic factors were compared between the 2 groups, including the correlation between the morphologic factors and postoperative outcomes.

RESULTS

Retears occurred in 26 of 99 cases (26%). In both the intact and retear groups, the University of California, Los Angeles, American Shoulder and Elbow Surgeons, and Constant scores improved postoperatively (P < .0001). The most common delamination shape was that of a more retracted articular layer in retears. We found no differences in retears in terms of the retraction length of the bursal layer, gap distance, and length of the intrasubstance cleavage. However, the retraction length of the articular layer differed significantly between the groups (P < .0001). No correlation between the morphologic factors and clinical outcomes was found.

CONCLUSIONS

Arthroscopic en masse transosseous-equivalent suture bridge repair is a useful technique in delaminated tears to achieve optimal repair outcomes. In addition, although there was no correlation between the morphologic factors and postoperative clinical outcomes, the retraction length of the articular layer was identified as a significant factor influencing repair integrity. We recommend emphasizing the reduction of tension within the articular layer during the repair procedure.

LEVEL OF EVIDENCE

Level III, retrospective comparison study.

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

OBJECTIVE

To analyze full-thickness rotator cuff tears, compare retraction patterns in delaminated and nondelaminated tendons, and correlate retraction distances with anteroposterior tear lengths.

MATERIALS AND METHODS

In 483 MR examinations reported as showing full-thickness cuff tear, two musculoskeletal radiologists independently characterized tendons as delaminated or nondelaminated. Tendon delamination was defined as either horizontal intra-substance splitting of bursal and articular layers by an intervening plane of fluid, or differential retraction of bursal and articular layers. In a subset of 144 shoulders with surgically proven full-thickness cuff tears (45 delaminated, 99 nondelaminated tendons), matched cohorts (n = 45) were further analyzed to compare tendon retraction distance, anteroposterior tear length and retraction ratios (retraction distance/anteroposterior length).

RESULTS

Delamination was present in 13% of 483 total tears, and 31% of 144 operated tears (p = 0.001). In nondelamination and delamination cohorts, mean anteroposterior tear length measured 30.0 and 31.5 mm respectively (p = 0.6). Although nondelaminated tendons showed mean retraction 31.5 mm, articular and bursal layers of delaminated tendons showed mean retractions 36.3 mm and 21 mm respectively (p < 0.0001). Anteroposterior tear length and retraction distance were significantly associated in all cuff tears (p < 0.0001). Retraction ratio for nondelaminated tendons (1.05) was significantly different from retraction ratios for articular (1.21) and bursal (0.70) layers of delaminated tendons (p < 0.0001).

CONCLUSION

In full-thickness rotator cuff tear, delaminated and nondelaminated tendons show significant differences in retraction distances, despite similarities in anteroposterior dimensions. Delaminated tendons are important to identify and report because they are more likely to fail conservative treatments and undergo operative repairs.

Clinical and Structural Outcomes after Arthroscopic Repair of Medium- to Massive-Sized Delaminated and Nondelaminated Rotator Cuff Tears

INTRODUCTION

Current evidence is controversial about the outcomes after the repair of the delaminated versus nondelaminated rotator cuff tears. The objective of this study was to evaluate the factors affecting delamination of the cuff and clinical and structural outcomes after en masse arthroscopic repair of delaminated versus nondelaminated cuff of varying sizes.

MATERIALS AND METHODS

A total of 233 patients with full-thickness posterosuperior cuff tears were divided in two groups: Group 1: Delaminated tears (n = 131) and Group 2: Nondelaminated tears (n = 102) of medium, large, and massive sizes. Both groups were evaluated by clinical scores (Constant-Murley [CM], American shoulder and elbow score [ASES]) and ultrasonography (USG), at a minimum followup of 2 years.

RESULTS

The mean followup was 45.47 months. There was a weak but statistically significant linear correlation (P = 0.02) between the increasing size of tear and delamination, whereas increasing age and duration of symptoms did not correlate with increasing tendency of delamination. Final followup USG analysis revealed that there was no significant difference (P = 0.55) between healing rates of Group 1 and Group 2. Further taking various tear sizes into account, USG revealed no significant difference between the healing rates of two groups. The mean overall final postoperative CM and ASES scores of two groups did not show any significant difference (CM; P = 0.36, ASES; P = 0.4). However, the clinical outcome was significantly better in the completely healed group as compared to partially healed or retear group.

CONCLUSIONS

A weak linear correlation between delamination and increasing size of the tear was noted. Although overall structural and clinical outcome is no different between two groups, the clinical outcomes of completely healed tear are better than partially healed ones.

LEVEL OF EVIDENCE

Level III, Retrospective comparative.

Comparison of En Masse Versus Dual-Layer Suture Bridge Procedures for Delaminated Rotator Cuff Tears

PURPOSE

To compare clinical outcomes between 2 suturing procedures, conventional en masse suture bridging (EMSB) and dual-layer suture bridging (DLSB), for delaminated rotator cuff tears.

METHODS

From January 2011 through December 2015, 98 consecutive cases with delaminated rotator cuff tears were included in this study (52 with EMSB and 46 with DLSB). The mean age was 65.0 ± 8.9 years (range, 38-85 years). The mean follow-up period was 28.0 ± 6.3 months (range, 24-40 months). The cases included 78 medium tears (1-3 cm) and 20 large tears (3-5 cm). The University of California, Los Angeles (UCLA) rating scale, the Simple Shoulder Test (SST), a visual analog scale for pain, and active range of motion of the shoulder preoperatively and 2 years after surgery were evaluated. Postoperative magnetic resonance imaging was obtained at 12 months after surgery.

RESULTS

Both the EMSB and DLSB groups showed improved clinical outcomes. Postoperative UCLA and SST scores were higher in the DLSB group than in the EMSB group (UCLA score, 33.2 ± 2.3 vs 32.0 ± 3.3 [P = .027]; SST score, 10.0 ± 1.0 vs 9.5 ± 1.2 [P = .014]). Postoperative abduction and external rotation of the shoulder were greater in the DLSB group than in the EMSB group (abduction, 160.1° ± 9.1° vs 154.8° ± 19.8° [P = .030]; external rotation, 53.7° ± 8.5° vs 46.1° ± 9.4° [P = .023]). Postoperative magnetic resonance imaging showed a retear in 7 of 52 cases in the EMSB group and 3 of 46 cases in the DLSB group, with no significant difference between groups.

CONCLUSIONS

The DLSB and EMSB procedures for delaminated rotator cuff tears improved clinical and radiographic outcomes, and the DLSB group achieved better postoperative range of motion of the shoulder than the EMSB group. The DLSB procedure is useful for repairing delaminated rotator cuff tears.

LEVEL OF EVIDENCE

Level III, retrospective, case-control, comparative study.

Comparison of Clinical and Anatomical Outcomes between Delaminated Rotator Cuff Tear and Single Layer Rotator Cuff Tear

Background

Delaminated rotator cuff tear is known to be a degenerative tear having a negative prognostic effect. This study undertook to compare the anatomical and clinical outcomes of delaminated tears and single layer tears.

Methods

Totally, 175 patients with medium to large rotator cuff tears enrolled for the study were divided into 2 groups, based on the tear pathology: single layer tear (group 1) and delaminated tear (group 2). Preoperatively, length of the remnant tendon, muscle atrophy of supraspinatus (SS), and fatty degeneration of SS and infraspinatus (IS) muscles were assessed on magnetic resonance imaging (MRI). For follow-up, the repair integrity of the rotator cuff was evaluated by ultrasonography. Clinical outcomes were assessed by evaluating the Constant score (CS) and Korean Shoulder Score (KSS).

Results

Retears were detected in 6 cases of group 1 (6.5%) and 11 cases of group 2 (13.3%). Although higher in group 2, the retear rate was significantly not different (p=0.133). Preoperative MRI revealed length of remnant tendon to be 15.46 ± 3.60 mm and 14.17 ± 3.16 mm (p=0.013), and muscle atrophy of SS (occupation ratio) was 60.54 ± 13.15 and 56.55 ± 12.88 (p=0.045), in group 1 and group 2, respectively. Fatty degeneration of SS and IS in both groups had no significant differences. Postoperatively, no significant differences were observed for CS and KSS values between the groups.

Conclusions

Delaminated rotator cuff tears showed shorter remnant tendon length and higher muscle atrophy that correlate to a negative prognosis. These prognostic effects should be considered during delaminated rotator cuff tear treatment.

Double-Layer Rotator Cuff Repair: Anatomic Reconstruction of the Superior Capsule and Rotator Cuff Improves Biomechanical Properties in Repairs of Delaminated Rotator Cuff Tears

BACKGROUND

Delamination in rotator cuff tears has been identified as a prognostic factor for negative outcome after repair, with a reported prevalence between 38% and 88%.

PURPOSE

To compare biomechanical properties of 3 repair techniques for delaminated rotator cuff tears.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eighteen fresh-frozen cadaveric shoulders were used to evaluate rotator cuff footprint reconstruction, contact area and pressure, displacement under cyclical loading, and load to failure of 3 double-row repair configurations: double-row suture repair with medial row knots (medially knotted bridge, mkB); knotless double-row repair using suture tapes (knotless bridge, klB); and knotless double-row, double-layer-specific repair (double-layer, DL). Dynamic pressure sensors were used to assess contact patterns at the footprint region in 0°, 30°, and 60° of glenohumeral abduction and 5 rotational positions (0°, 30° of internal rotation, 30° of external rotation, 60° of internal rotation, 60° of external rotation). Optical markers were used to document whole tendon and individual layer displacement after rotator cuff repair under cyclical loading for 200 cycles (10 N to 100 N at 1 Hz). Specimens were then loaded monotonically to failure at a rate of 33 mm/min.

RESULTS

Mean contact area and footprint restoration were highest in the DL group at 60° of glenohumeral abduction for all rotational positions (mkB mean ± SD, 195.4 ± 54.3 mm², 66.7% ± 19.7%; klB, 250.6 ± 34.9 mm², 76.2% ± 10.3%; DL, 318.4 ± 36.6 mm², 109.1% ± 24.0%; P < .001). The double-layer-specific repair showed the least displacement under cyclical loading (mkB mean ± SD, 0.53 ± 0.18 mm; klB, 0.79 ± 0.37 mm; DL, 0.31 ± 0.24 mm; P = .029), most closely resembling the native tendon. Peak loads at failure were comparable between repair groups (mkB mean ± SD, 366.92 ± 70.59 N; klB, 280.05 ± 77.66 N; DL, 398.35 ± 109.04 N; P = .083).

CONCLUSION

Anatomic restoration of the superior capsular and tendon insertion in delaminated rotator cuff tears with a double-layer-specific repair configuration demonstrated superior footprint restoration with increasing abduction, while providing construct displacement comparable to the native tendon under cyclical loading. Peak load at failure was comparable between repair constructs.

CLINICAL RELEVANCE

The prevalence and clinical importance of delaminated rotator cuff tears have long been underestimated. Anatomically correct individual reconstruction of the superior capsule and rotator cuff could restore near-native biomechanics and potentially reduce the risk of rotator cuff repair failure.

Characteristics of the patients with delaminated rotator cuff tear

Purpose: The purpose of this study was to analyze factors relating to delamination in full-thickness rotator cuff tears.

Methods: 126 patients with full-thickness rotator cuff tears treated by arthroscopic rotator cuff repair were the subjects of this study. There were 52 females and 74 males whose average age was 64.2 years. Fifty-three patients had history of trauma. The average duration of disorder was 29.5 weeks. Nineteen patients were diagnosed with diabetes. On types of the tears, small tear was observed in 59 patients, medium tear in 47 patients, large tear in 6 patients, and massive tear in 14 patients. The average size of tear was 1.98 cm. Delamination of the torn cuff was observed in 45 patients. Factors compared between the patients without delamination and those with delamination were as follows: gender and age of the patients, history of trauma, duration of disorder, diabetes, smoking, size and number of rotator cuff tears.

Results: The delamination rate of the smoking patients was significantly higher than non-smoking patients. The delamination rate of patients with more than two tendon tears was significantly higher than those with only one tendon tear. The average size of tear with delamination was significantly larger than that of tear without delamination. The other factors were not related to delamination.

Conclusions: This study suggests that smoking, size of tear and number of torn cuffs are associated with delamination. The progression of torn cuff, anatomical features and nicotine of smoking affect the causes of delaminated tear of rotator cuff.

Factors affecting rotator cuff integrity after arthroscopic repair for medium-sized or larger cuff tears: a retrospective cohort study

BACKGROUND

We wished to identify the preoperative prognostic factors associated with structural integrity after repair of medium-sized and larger rotator cuff tears and to determine the cutoff values using receiver operating characteristic curve analysis.

METHODS

The study included 180 patients with medium-sized and larger rotator cuff tears. Each had a minimum 2-year postoperative follow-up by magnetic resonance imaging. We assessed several patient-related and disease-related preoperative factors using univariate and multivariate logistic regression analysis. To determine the cutoff value for the significant variables, receiver operating characteristic curve analysis was performed.

RESULTS

Retears occurred in 28 of the 180 patients (15.6%). Univariate analysis found that retear was significantly affected by the type of work and pattern of tear. The rate of retear was significantly increased in diabetes and with increasing tear size, extent of retraction, delamination, and fatty infiltration. Furthermore, reduced remnant tendon length, distance from the musculotendinous junction to the face of the glenoid, occupation ratio, and acromiohumeral interval were also significant risk factors. In the multivariate analysis, body mass index, diabetes, dyslipidemia, extent of retraction, delamination, distance from musculotendinous junction to face of glenoid, occupation ratio, fatty infiltration of infraspinatus, and acromiohumeral interval remained significant risk factors. The extent of retraction (22.2 mm) and the occupation ratio (53.5%) showed highly accurate cutoff values for predicting retear.

CONCLUSION

Multiple factors influenced the healing process after rotator cuff repair. The best predictors were the extent of retraction and occupation ratio, which could help assist in determining the prognosis after rotator cuff repairs.

Location and thickness of delaminated rotator cuff tears: cross-sectional analysis with surgery record review

Background

To facilitate better treatment, we analyzed morphologic features of delamination from the viewpoint of the location of delamination and the thickness of each layer.

Materials and Methods

Of 270 shoulders that consecutively underwent arthroscopic rotator cuff repair, 210 were included. During the operation, the surgeon assessed the size of the rotator cuff tear, determined the presence and location of delamination, and compared the thickness between superficial and deep layers if delamination was present. Immediately after the operation, the surgeon wrote down the data in the record form. The authors retrospectively referred to these surgical records to investigate those items.

Results

Delamination was found in 111 of 210 shoulders. The overall preoperative Constant score did not significantly differ between the 2 groups. In terms of the location, 7.2% cases had delamination in the anterior part, 74.8% in the posterior part, and 18.0% in both parts (Fleiss κ = 0.9). The larger the rotator cuff tear, the more frequently the delamination was limited to the posterior part (trend P = .001). As for layer thickness comparison, 40.0% of the shoulders with small tears, 38.8% with medium tears, 66.0% with large tears, and 80.0% with massive tears had a thicker deep layer than superficial layer (Fleiss κ = 0.9). The larger the size of the rotator cuff tear, the more frequently the deep layer was thicker than the superficial layer (trend P = .001).

Conclusions

The larger the rotator cuff tear, the more carefully shoulder surgeons should observe and treat the posterior and deep part of delamination.

An Arthroscopic Knotless Technique for Anatomical Restoration of the Rotator Cuff and Superior Capsule: The Double-Layer Cinch Bridge

Rotator cuff repairs are the most common procedures in shoulder surgery, but still show long-term retear rates of up to 70%. Nonanatomic reconstruction is one possible cause of repair failure. The rotator cuff histologically consists of 5 separate layers of which 2 are macroscopically identifiable: the superior or tendinous layer and the inferior or capsule-ligamentous layer. In case of rotator cuff tears, these layers are often retracted to different degrees. The intraoperative detectable prevalence of rotator cuff delamination reaches up to 85%. Anatomical rotator cuff repair, which also includes restoration of the layered structure, could re-establish native tendon morphology and thus potentially decreases retear rates. The use of a knotless construct to avoid cuff strangulation and maintaining tendon perfusion could further decrease the risk of repair failure. Double-layer reconstructions are challenging and time consuming because each layer needs to be penetrated separately. Only few studies reported about double-layer reconstruction of the posterosuperior rotator cuff. This Technical Note is the first to present an arthroscopic knotless transosseous-equivalent double-layer repair technique.

Comparison of histologic healing and biomechanical characteristics between repair techniques for a delaminated rotator cuff tear in rabbits

BACKGROUND

The purpose of this study was to compare histologic healing and biomechanical characteristics between 2 repair techniques (layer by layer, repair of each layer to bone separately; and whole layer, repair of each layer to the bone en masse) for delaminated rotator cuff tear.

MATERIALS AND METHODS

Rabbits were used as subjects and classified into 2 groups: group A, right side, the layer-by-layer repair group; and group B, left side, the whole-layer repair group. Histologic evaluations were done at 3 weeks (n = 7) and 6 weeks (n = 4) after operation. Biomechanical tests to evaluate the tensile property were done at time 0 (n = 5) and 3 weeks (n = 5) after operation.

RESULTS

Histologic healing improved in all groups. A smaller cleft was found between layers in group B compared with the cleft in group A at 3 weeks after operation. At time 0, group A showed a higher yield load and ultimate failure load (67 ± 10.5 N and 80 ± 7.8 N, respectively). However, at 3 weeks after operation, group B showed a higher yield load (48 ± 7.6 N).

CONCLUSIONS

In the delaminated rotator cuff tear model in the rabbit, the whole-layer repair showed a narrow gap between layers and a higher yield load at 3 weeks after operation. Surgical techniques that unite the cleft in a delaminated tear could improve biomechanical strength after operation.

Critical Size Bone Defect Healing Using Collagen-Calcium Phosphate Bone Graft Materials

The need for bone graft materials to fill bony voids or gaps that are not related to the intrinsic stability of the bone that arise due to trauma, tumors or osteolysis remains a clinically relevant and significant issue. The in vivo response of collagen-tricalcium phosphate bone graft substitutes was evaluated in a critical size cancellous defect model in skeletally mature rabbits. While the materials were chemically virtually identical, new bone formation, implant resorption and local in vivo responses were significantly different. Differences in the in vivo response may be due, in part, collagen source and processing which influences resorption profiles. Continued improvements in processing and manufacturing techniques of collagen-tricalcium phosphate bone graft substitutes can result in osteoconductive materials that support healing of critical size bone defects even in challenging pre-clinical models.

Repair of Rotator Cuff Tear With Delamination: Independent Repairs of the Infraspinatus and Articular Capsule

We propose a technique to repair delamination, which often occurs during rotator cuff repair surgery. We have reported that the infraspinatus occupies most of the greater tuberosity with the articular capsule attached to a very wide area, and that the superficial layer is mainly composed of the infraspinatus, and the deep layer is mainly composed of the articular capsule. To repair such delamination with consideration of the detailed anatomy, we developed the following repair method with independent repair of the superficial layer (infraspinatus) and the deep layer (articular capsule): (1) the deep layer is pulled laterally and joined to the medial margin of the greater tuberosity using 4 simple sutures from 2 anchors; (2) the paired limbs (same color) of 4 knots are passed over the posterior leaf of the superficial layer at intervals; (3) a push-in anchor loaded with 1 thread each of 4 knots is placed on the anterolateral corner of the greater tuberosity to pull the superficial layer anterolaterally; (4) another push-in anchor (remaining threads) is pushed on the posterior corner of the greater tuberosity. We believe that this technique can recover the function of both the articular capsule and rotator cuff, thereby facilitating better treatment outcomes after surgery.

Retraction pattern of delaminated rotator cuff tears: dual-layer rotator cuff repair

BACKGROUND

There has been no report to date regarding retraction patterns of delaminated rotator cuff tears. The purpose of this study was to evaluate the incidence and tearing patterns of delamination and repair integrity after the dual-layer repair of delaminated cuff tears.

METHODS/DESIGN

A consecutive series of 64 patients with posterosuperior rotator cuff tears underwent arthroscopic rotator cuff repair from August 2011 to September 2012. Among the patients, 53 who received either dual-layer double-row (DLDR) repair or dual-layer suture bridge (DLSB) repair and 11 who received a single-layer repair were evaluated. The mean follow-up period after surgery was 26.5 months. The retraction direction of the deep and superficial layers was analyzed, and the integrity of the repaired constructs was determined in 37 patients through magnetic resonance imaging at a mean of 12.1 months after surgery.

RESULTS

The incidence of delamination was 82.8 %. Posteromedial retraction of the deep and superficial layers was observed in 98.1 and 88.5 % of cases, respectively. The Constant score and UCLA score increased preoperatively to postoperatively, showing no significant differences between the dual-layer repair group and single-layer repair group. Retear was found in two (7.6 %) patients in the dual-layer repair group and three (27.2 %) patients in the single-layer repair group (p = 0.016).

CONCLUSIONS

Differential rotator cuff repair strategies are needed to address rotator cuff tears, since recent studies have changed our concept of rotator cuff tears. We have focused on three areas: incidence, retraction patterns, and clinical outcomes. The incidence of delamination was extremely high. Both the superficial layer and deep layer were mainly retracted posteromedially. The retraction of the deep layer and superficial layer may be affected by the infraspinatus. Dual-layer rotator cuff repair based on the retraction pattern of delamination is recommended for improvement of repair integrity and of clinical outcomes.

Evidence of healing of partial-thickness rotator cuff tears following arthroscopic augmentation with a collagen implant: a 2-year MRI follow-up

BACKGROUND

partial-thickness rotator cuff tears frequently enlarge due to increased local strain and often progress to full-thickness tears. Studies suggest the addition of new tendinous tissue to injured cuff tendons would significantly decrease peak strain, possibly protecting against tear progression. The aim of this study was to assess the ability of a highly-porous collagen implant to induce new tissue formation and limit tear progression when placed on the bursal surface of partial-thickness cuff tears.

METHODS

following arthroscopic subacromial decompression, the implant was attached to the bursal surface of the supraspinatus tendon in a prospective series of 13 consecutive patients with intermediate - (3-6 mm) to high-grade (>6 mm) partial - thickness cuff tears (5 articular, 3 bursal, 5 intra-substance). Tendon thickness, defect size, and tendon quality were evaluated using magnetic resonance imaging (MRI) preoperatively and at 3, 6, 12, and 24 months postoperatively. Clinical outcomes were assessed using the Constant and American Shoulder and Elbow Society scores at the same preoperative and follow-up times. All 13 patients completed all follow-up exams (mean length of follow-up 27.0 months, range 23.3-32.0); no patients were lost to follow-up.

RESULTS

the implant induced significant new tissue formation in all patients by 3 months (mean increase in tendon thickness 2.2 ± 0.26 mm). This tissue matured over time and became radiologically indistinguishable from the underlying tendon. The partial-thickness cuff tears showed consistent filling of the defects, with complete healing in 7 patients at 12 months, and a progressive improvement in tendon quality in the remaining patients. No tear progression was observed by MRI in any of the patients at 24 months. All clinical scores improved significantly over time. At 24 months, 12 of 13 patients (92%) had satisfactory or better results.

CONCLUSIONS

the results of this clinical study demonstrated the ability of a highly-porous collagen implant to induce new tendon-like tissue formation and create an environment conductive to the healing of partial-thickness cuff tears.

Conventional En Masse Repair Versus Separate Double-Layer Double-Row Repair for the Treatment of Delaminated Rotator Cuff Tears

BACKGROUND

The rotator cuff tendon is known to exert a shear force between the superficial and deep layers. Owing to this characteristic, separate repair of delaminated rotator cuff tears has been introduced for the restoration of the physiological biomechanics of the rotator cuff. However, whether conventional en masse repair or separate repair is superior is controversial in terms of outcomes.

PURPOSE

To compare clinical outcomes between conventional en masse repair and separate double-layer double-row repair for the treatment of delaminated rotator cuff tears.

STUDY DESIGN

Randomized controlled study; Level of evidence, 2.

METHODS

Between August 2007 and March 2014, a total of 82 patients who underwent arthroscopic rotator cuff repair of a delaminated tear were enrolled and randomized into 2 groups. In group 1 (n = 48), arthroscopic conventional en masse repair was performed. In group 2 (n = 34), separate double-layer double-row repair was performed. The American Shoulder and Elbow Surgeons score, Constant score, Simple Shoulder Test score, and visual analog scale (VAS) score for pain and range of motion (ROM) were assessed before surgery; at 3, 6, and 12 months after surgery; and at the last follow-up visit. Magnetic resonance imaging (MRI) was performed at 12 months postoperatively to examine the retear rate and pattern.

RESULTS

There was no significant difference between groups in the preoperative demographic data, including patient age, sex, symptom duration, tear size, and functional scores (P > .05). The mean follow-up period was 25.9 ± 1.2 months. Significant improvements in functional and pain scores were observed in both groups at the last follow-up visit. However, no significant differences in functional scores and ROM were found between the 2 groups at each time point, except that group 2 had significantly lower VAS pain scores (P < .05) at 3, 6, and 12 months postoperatively. Eight (17%) of 48 patients in group 1 and 6 (18%) of 34 patients in group 2 showed retears on MRI at 12-month follow-up (P > .05).

CONCLUSION

Both conventional en masse repair and separate double-layer double-row repair were effective in improving clinical outcomes in the treatment of delaminated rotator cuff tears. Lower pain scores were seen in patients who underwent separate double-layer double-row repair.

Surgical Results of Delaminated Rotator Cuff Repair Using Suture-Bridge Technique With All-Layers or Bursal Layer-Only Repair

BACKGROUND

There are no known studies that have investigated the effect on delaminated rotator cuff tears of bursal layer-only repair when full-thickness repair would put the articular layer under tension, compared with all-layers repair when full-thickness repair is feasible.

HYPOTHESIS

Better outcomes will be seen in the bursal layer-only repair, as the articular layer would be under tension when repaired onto its footprint during the all-layers repair.

STUDY DESIGN

Cohort study; Level of evidence 3.

METHODS

This study included 112 patients who underwent arthroscopic rotator cuff repair for posteriorly delaminated tears of either all layers (group A) or the bursal layer alone (group B). If the articular layer was able to be reduced onto its footprint, the patient was assigned to group A; if such reduction was not possible or was only marginally possible under significant tension, the patient was assigned to group B. Pain scored on a visual analog scale (VAS) was assessed, as were subjective shoulder value (SSV), University of California, Los Angeles (UCLA) shoulder score, American Shoulder and Elbow Surgeons (ASES) score, and shoulder active range of motion (ROM). Postoperative magnetic resonance arthrography (MRA) or computed tomographic arthrography (CTA) was undertaken 6 months postoperatively for structural integrity assessment.

RESULTS

After 2 years, the VAS pain score (group A, from 6.5 to 1.2; group B, from 6.4 to 1.2), SSV (group A, from 38.3 to 89.4; group B, from 38.0 to 90.1), ASES score (group A, from 36.4 to 90.4; group B, from 38.0 to 90.8), UCLA shoulder score (group A, from 15.3 to 30.7; group B, from 15.0 to 31.3), and ROM improved significantly in both groups compared with preoperative values (P < .001). However, none of these values differed significantly between groups. On follow-up MRA or CTA images, there was no significant difference in the retear rate between group A (28%; 16/57) and group B (24%; 11/45).

CONCLUSION

The all-layers repair did not produce better clinical outcomes or structural integrity than the bursal layer-only repair. The study findings indicate that if repair of the articular layer is possible only under significant tension or is not reparable, rather than all-layers repair by force, bursal-layer repair without incorporating the articular layer may produce comparable clinical outcomes and structural integrity in the delaminated rotator cuff tear.

Lengthening of the subscapularis tendon as a sign of partial tearing in continuity

BACKGROUND

The quantification of a subscapularis tendon lesion may be difficult on magnetic resonance imaging, as well as during arthroscopic inspection. Consequently, the surgical decision of whether to only debride a degenerated tendon or to lateralize the more intact tendon portion may be arbitrary. This study aims to quantify the length of the subscapularis tendon as a sign of partial tendon tearing.

METHODS

We retrospectively identified 92 magnetic resonance arthrography studies of suspected rotator cuff lesions obtained 3 months before shoulder arthroscopy. The myotendinous junction was identified, and the subscapularis tendon and muscle lengths were measured. Findings on arthroscopy performed later were used as the diagnostic gold standard for tendon integrity and compared with the magnetic resonance data.

RESULTS

Arthroscopy showed an intact subscapularis tendon in 43 patients, tendinopathy in 21 patients, and a partial rupture in 28 patients. The mean subscapularis tendon lengths were 40 mm in cases of intact subscapularis musculotendinous units, 45 mm in cases of tendinopathy, and 53 mm in cases of partial tears, whereas the mean subscapularis muscle lengths were 105 mm, 94 mm, and 95 mm, respectively, in these groups.

CONCLUSION

Partial tears of the subscapularis tendon lead to muscle shortening by approximately 10% and elongation of the tendon by approximately 32%, which may be interpreted as muscle retraction and a tendon rupture in continuity. If the subscapularis tendon has an apparent length of greater than 60 mm, the probability of a tear is 98%. Determination of the tendon length may therefore be a useful additional tool to quantify the integrity of the subscapularis tendon and degree of myotendinous retraction.

Intratendinous rupture of the supraspinatus: anatomical and functional results of 24 operative cases

INTRODUCTION

The aim was to describe the natural history of intratendinous partial rotator cuff tears as well as the anatomical and clinical results of surgical treatment of a cohort of 24 patients.

PATIENTS AND METHODS

There were 14 men and 10 women with a mean age of 50 years. The right shoulder was involved in 17 cases. For 16 cases, a progressive history of shoulder pain was reported. Pre-operatively, a painful and positive Jobe's sign was observed in only 13 cases. Pre-operative mean absolute constant score was 63.52 points. Based on standard MRI, intratendinous lesions were diagnosed on the coronal view with hyper-signal within the tendon in the T2 FatSat sequence. No fatty infiltration was noted. Fourteen open and 10 arthroscopic repairs were performed.

RESULTS

Patients were reviewed with clinical assessment and MRI. The final Constant score was 81.3 points with a mean gain of 18.5 points. Patients were back to work after a mean of 5.8 months and to sports after 6 months. The mean subjective result was of 8.9/10. Three cases of reflex sympathetic dystrophy were observed.

DISCUSSION

Intratendinous tears of the supraspinatus tendon are rare and difficult to diagnose. Diagnosis relies on MRI (T2 FatSat). Trauma is not usually described. Chronic calcifying tendonitis may also contribute to the development of such tears. There is no associated fatty infiltration of the muscle. The Jobe's test is frequently painful or positive. Arthroscopic resection of the tendon insertion with reinsertion to the greater tuberosity seems to be the optimal treatment.

LEVEL OF EVIDENCE

Retrospective study, IV.

Delaminated tears of the rotator cuff: prevalence, characteristics, and diagnostic accuracy using indirect MR arthrography

OBJECTIVE. The purpose of this study was to evaluate the prevalence, radiologic characteristics, and accuracy of diagnosing delaminated tears at the supraspinatus tendon-infraspinatus tendon (SST-IST) on indirect MR arthrography. MATERIALS AND METHODS. Of 531 consecutive shoulders that underwent indirect MR arthrography, 231 shoulders with tears at the SST-IST were included. On the MR images, delaminated tears at the SST-IST, defined as intratendinous horizontal splitting between the articular and bursal layers of the SST-IST with or without different degrees of retraction between the two layers, were identified and classified into six types. Other radiologic findings of the SST-IST, such as the presence of intramuscular cysts, were evaluated. We used video records of 127 arthroscopic surgeries to determine the diagnostic accuracy of indirect MRI for the detection of the delaminated tears at the SST-IST. RESULTS. On MRI, 56% (129/231) of shoulders with SST-IST tears had delaminated tears. Articular-delaminated full-thickness tears (n = 58) and articular-delaminated partial-thickness tears (n = 64) were the most common types. Approximately 82% (36/44) of articular-delaminated full-thickness tears occurring at the SST were combined with articular-delaminated partial-thickness tears at the IST. SST-IST footprint tears and intramuscular cysts were significantly more common in the shoulders with delaminated tears. The sensitivity and specificity of indirect MR arthrography for detection of delaminated tears were 92% and 94%, respectively. CONCLUSION. On indirect MR arthrography, approximately half of the shoulders with SST-IST tears had delaminated tears. The diagnostic accuracy of indirect MR arthrography for detection of delaminated tears was high.

Delaminated rotator cuff tear: extension of delamination and cuff integrity after arthroscopic rotator cuff repair

BACKGROUND

The purpose of this study was to evaluate the extension of delamination and the cuff integrity after arthroscopic repair of delaminated rotator cuff tears.

METHODS

Sixty-five patients with delaminated rotator cuff tears were retrospectively reviewed. The delaminated tears were divided into full-thickness delaminated tears and partial-thickness delaminated tears. To evaluate the medial extension, we calculated the coronal size of the delaminated portion. To evaluate the posterior extension, we checked the tendon involved. Cuff integrity was evaluated by computed tomography arthrography.

RESULTS

The mean medial extension in the full-thickness and partial-thickness delaminated tears was 18.1 ± 6.0 mm and 22.7 ± 6.3 mm, respectively (P = .0084). The posterior extension into the supraspinatus and the infraspinatus was 36.9% and 32.3%, respectively, in the full-thickness delaminated tears, and it was 27.7% and 3.1%, respectively, in the partial-thickness delaminated tears (P = .0043). With regard to cuff integrity, 35 cases of anatomic healing, 10 cases of partial healing defects, and 17 cases of retear were detected. Among the patients with retear and partial healing of the defect, all the partially healed defects showed delamination. Three retear patients showed delamination, and 14 retear patients did not show delamination; the difference was statistically significant (P = .0001).

CONCLUSION

The full-thickness delaminated tears showed less medial extension and more posterior extension than the partial-thickness delaminated tears. Delamination did not develop in retear patients, but delamination was common in the patients with partially healed defects.

Rotator cuff tear: A detailed update

Rotator cuff tear has been a known entity for orthopaedic surgeons for more than two hundred years. Although the exact pathogenesis is controversial, a combination of intrinsic factors proposed by Codman and extrinsic factors theorized by Neer is likely responsible for most rotator cuff tears. Magnetic resonance imaging remains the gold standard for the diagnosis of rotator cuff tears, but the emergence of ultrasound has revolutionized the diagnostic capability. Even though mini-open rotator cuff repair is still commonly performed, and results are comparable to arthroscopic repair, all-arthroscopic repair of rotator cuff tear is now fast becoming a standard care for rotator cuff repair. Appropriate knowledge of pathology and healing pattern of cuff, strong and biological repair techniques, better suture anchors, and gradual rehabilitation of postcuff repair have led to good to excellent outcome after repair. As the healing of degenerative cuff tear remains unpredictable, the role of biological agents such as platelet-rich plasma and stem cells for postcuff repair augmentation is still under evaluation. The role of scaffolds in massive cuff tear is also being probed.

Arthroscopic lamina-specific double-row fixation for large delaminated rotator cuff tears

Delamination is a commonly observed finding at the time of rotator cuff repair, but few studies have described the surgical techniques used for delaminated rotator cuff tears (RCTs) or their clinical outcomes. We developed a technique using a combination of a double row and an additional row, which we call lamina-specific double-row fixation, for large delaminated RCTs. The lamina-specific double-row technique is performed using an additional row (lamina-specific lateral row) of suture anchors placed between the typical medial and lateral rows of suture anchors. The technique is performed as follows: (1) medial-row sutures are passed through the inferior (articular-side) and superior (bursal-side) layers in a mattress fashion; (2) lamina-specific lateral-row simple sutures are passed through the inferior layer; and (3) lateral-row simple sutures are passed through the superior layer. We believe that this technique offers the following advantages: (1) creation of a larger area of contact between the inferior layer and the footprint, (2) higher initial fixation strength of the articular-side components of the repaired rotator cuff tendon, and (3) an adaptation between the superficial and inferior layers. This technique represents an alternative option in the operative treatment of large delaminated RCTs.

Is posterior delamination in arthroscopic rotator cuff repair hidden to the posterior viewing portal?

PURPOSE

The purposes of this study were (1) to examine whether posterior delamination is hidden to the most commonly used posterior viewing portal compared with differential rotator cuff portals and (2) to observe posterior delamination patterns so that a treatment-based classification system may be proposed.

METHODS

One-hundred thirty consecutive patients undergoing arthroscopic rotator cuff repair by 4 different surgeons were evaluated for the presence of posterior delamination viewable through the posterior, posterolateral, and lateral portals. Randomized arthroscopic pictures were viewed by 2 independent blinded observers, and the Fleiss κ was used to assess inter-reliability agreement. In addition, patterns of posterior delamination and surgical treatment were assessed.

RESULTS

The incidence of posterior delamination was 88%. Only 11% of cases were visualized through the posterior portal, whereas 70% and 100% were visualized through the posterolateral and lateral portals, respectively. The Fleiss κ was 0.78 (95% confidence interval, 0.73 to 0.83), indicating substantial agreement. Three general patterns of posterior delamination with specific surgical repair strategies were identified and subclassified into 5 types: type A1, full-thickness tears with extensive posterior delamination separating the rotator cuff into 2 layers and sometimes with dissociation of the rotator cable; type A2, bursal-sided partial-thickness tears with posterior delamination; type B1, delamination with an L-shaped bursal layer tear and crescent-shaped articular layer tear; type B2, a partial-thickness articular-sided tear with extensive posterior delamination; and type C, extensive degeneration with multiple longitudinal bursal-sided tears.

CONCLUSIONS

The incidence of posterior delamination is extremely high, and most of these lesions are missed if one is viewing from just the posterior portal. Differential rotator cuff portals are needed to appreciate and treat posterior delamination. Patterns of delamination can be classified according to surgical repair strategy. It is important to recognize that the rotator cable may delaminate from the cuff and not to mistake it for a "retracted" articular layer, as previously described.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

A systematic review of the histological and molecular changes in rotator cuff disease

INTRODUCTION

The pathogenesis of rotator cuff disease (RCD) is complex and not fully understood. This systematic review set out to summarise the histological and molecular changes that occur throughout the spectrum of RCD.

METHODS

We conducted a systematic review of the scientific literature with specific inclusion and exclusion criteria.

RESULTS

A total of 101 studies met the inclusion criteria: 92 studies used human subjects exclusively, seven used animal overuse models, and the remaining two studies involved both humans and an animal overuse model. A total of 58 studies analysed supraspinatus tendon exclusively, 16 analysed subacromial bursal tissue exclusively, while the other studies analysed other tissue or varying combinations of tissue types including joint fluid and muscle. The molecular biomarkers that were altered in RCD included matrix substances, growth factors, enzymes and other proteins including certain neuropeptides.

CONCLUSIONS

The pathogenesis of RCD is being slowly unravelled as a result of the significant recent advances in molecular medicine. Future research aimed at further unlocking these key molecular processes will be pivotal in developing new surgical interventions both in terms of the diagnosis and treatment of RCD.