Medial-row failure after arthroscopic double-row rotator cuff repair

Arthroscopic Double-Pulley Suture-Bridge Repair of Supraspinatus Tendon Tear

At present, the suture bridge is a widely used surgical pattern in the treatment of supraspinatus tendon tear, but the shortcomings of a suture bridge, including expensive lateral-row anchor and increased type 2 retear rate, is obvious. The double-pulley suture-bridge described in this Technical Note uses a double-loaded suture anchor (medial-row anchor) as lateral-row anchor instead of traditional lateral-row anchor, combined with double-pulley technology forming suture-bridge in treatment of supraspinatus tendon tears. The surgical technique is described in pearls, pitfalls, advantages, and disadvantages.

A comparison between knotted and knotless medial row of suture bridge technique in arthroscopic rotator cuff repair surgery: a meta-analysis

BACKGROUND

The shoulder arthroscopic suture bridge technique is currently very popular, but scientific evidence relating to the clinical outcomes of the medial row with or without knots has not been systematic reviewed.

PURPOSE

The purpose of this study was to compare the clinical outcomes of knotted versus knotless double-row suture bridges for rotator cuff repairs.

STUDY DESIGN

Meta-analysis.

METHOD

Five databases that contain literature in English were searched (Medline, PubMed, Embase, Web of Science, and the Cochrane Library), with a focus on works published between 2011 and 2022. Clinical data relating to arthroscopic rotator cuff repair with the suture bridge approach was examined and the outcomes of medial row knotting contrasted with that of the knotless technique. The search phrase used was: (double row) AND (rotator cuff) AND (repair), and the search method is subject term plus free word search. Literature quality evaluation was performed using the Cochrane "risk of bias" tool 1.0 and the Newcastle-Ottawa scale quality assessment instrument.

RESULTS

One randomized controlled trial, four prospective cohort studies, and five retrospective cohort studies were included in this meta-analysis. Data pertaining to 1146 patients was drawn from these ten original papers and analyzed. Meta-analyses that were performed on 11 postoperative outcomes revealed that none of the differences were statistically significant (P > 0.05) and that the publications were unbiased (P > 0.05). Postoperative retear rate and postoperative retear categorization were the outcomes assessed. Scores on postoperative pain, forward flexion, abduction, and external rotation mobility were collated and evaluated. The University of California, Los Angeles scoring systems in the first year following surgery, the American Shoulder and Elbow Surgeons score and Constant scales in the first and second years after surgery were the secondary outcomes spotlighted in this study.

CONCLUSION

The clinical outcomes of shoulder arthroscopic rotator cuff repair with the suture bridge technique with or without a knotted medial row was proven to be equivalent. These outcomes are about postoperative retear, postoperative retear classification, postoperative shoulder function score, postoperative shoulder mobility, and postoperative pain, respectively. It should be noted that the conclusions are based on short-term clinical follow-up data.

Rates of medial and lateral row failure and risk factors for Re-tear in arthroscopic double row rotator cuff repair

A common postoperative complication after rotator cuff repair is re-tear requiring a secondary procedure. Double row and trans-osseous equivalent repair techniques have become increasingly popular in recent years, however repair failure remains a relatively common complication after primary rotator cuff repair. A retrospective observational study of 389 consecutive patients undergoing arthroscopic double-row rotator cuff repair from February 1, 2014 to March 31, 2020 was conducted. Univariate and multivariate statistics were used to assess differences in demographics, comorbidities, and tear characteristics between patients who experienced re-tear and those who did not. Repair failures were confirmed by plain MRI or intraoperatively during repeat surgical treatment. A subgroup analysis of patients who experienced re-tear due to medial row failure was conducted. The overall re-tear rate was 8.2% (32 patients). Six patients (1.5%) experienced medial row failure, while 26 patients (6.7%) experienced lateral row failure. The average time to re-tear was 279.3 ± 291.2 days. On multivariate analysis, patients with Goutallier Classification ≥3 (OR: 4.274, p = 0.046) and 3 anchor repair (OR: 5.387, p = 0.027) were at significantly increased risk for any re-tear after controlling for other tear characteristics. No statistically significant independent risk factors for medial row failure were identified after controlling for confounding variables. Goutallier classification greater than 3 and a primary repair with 3 anchors are significant risk factors for re-tear after double row rotator cuff repair, however they are not associated with increased occurrence of medial row failure. Further evaluation of risk factors for medial row failure is required to avoid this rare but serious re-tear pattern.

Risk Factors and Corresponding Management for Suture Anchor Pullout during Arthroscopic Rotator Cuff Repair

INTRODUCTION

Due to the aging of the population, the incidence of rotator cuff tears is growing. For rotator cuff repair, arthroscopic suture-anchor repair has gradually replaced open transosseous repair, so suture anchors are now considered increasingly important in rotator cuff tear reconstruction. There are some but limited studies of suture anchor pullout after arthroscopic rotator cuff repair. However, there is no body of knowledge in this area, which makes it difficult for clinicians to predict the risk of anchor pullout comprehensively and manage it accordingly.

METHODS

The literature search included rotator cuff repair as well as anchor pullout strength. A review of the literature was performed including all articles published in PubMed until September 2021. Articles of all in vitro biomechanical and clinical trial levels in English were included. After assessing all abstracts (n = 275), the full text and the bibliographies of the relevant articles were analyzed for the questions posed (n = 80). Articles including outcomes without the area of interest were excluded (n = 22). The final literature research revealed 58 relevant articles. Narrative synthesis was undertaken to bring together the findings from studies included in this review.

RESULT

Based on the presented studies, the overall incidence of anchor pullout is not low, and the incidence of intraoperative anchor pullout is slightly higher than in the early postoperative period. The risk factors for anchor pullout are mainly related to bone quality, insertion depth, insertion angle, size of rotator cuff tear, preoperative corticosteroid injections, anchor design, the materials used to produce anchors, etc. In response to the above issues, we have introduced and evaluated management techniques. They include changing the implant site of anchors, cement augmentation for suture anchors, increasing the number of suture limbs, using all-suture anchors, using an arthroscopic transosseous knotless anchor, the Buddy anchor technique, Steinmann pin anchoring, and transosseous suture repair technology.

DISCUSSION

However, not many of the management techniques have been widely used in clinical practice. Most of them come from in vitro biomechanical studies, so in vivo randomized controlled trials with larger sample sizes are needed to see if they can help patients in the long run.

The "Greenhouse" Technique Using Knotless Single-Row Suture Bridge Combined With Bone Marrow Stimulation for the Arthroscopic Treatment of Rotator Cuff Tears

To simplify the arthroscopic rotator cuff repair technique and improve tendon healing, we have developed a method named the "Greenhouse" technique to repair rotator cuff. With bone marrow stimulation combined with knotless single-row suture bridge fixation, we provide a technique for reliable cuff fixation with enhanced biological features.

The Application of H-Loop in Arthroscopic Knotless Double-Row Rotator Cuff Repairs

Objective

To determine the functional outcomes after a novel method of H‐loop knotless double‐row technique in patients with rotator cuff tears.

Method

From June 2020 to September 2020, a total of six patients (five women, one man) with arthroscopic rotator cuff repair using the H‐loop knotless double‐row technique were enrolled in our study. The average age is 54 years (range: 50–61 years). The preoperative and final follow‐up clinical outcome were evaluated using the American Shoulder and Elbow Surgeons (ASES) score, visual analog scale (VAS), University of California Los Angeles (UCLA) score, and Constant–Murley score. The active shoulder range of motion (ROM) was also collected preoperatively and postoperatively at the final follow‐up (forward flexion and abduction). Accordingly, intraoperative and postoperative complications were observed as well.

Result

There were six patients that underwent arthroscopic rotator cuff repair using the H‐loop knotless double‐row technique. The average follow‐up period was 7.52 ± 0.70 months. The VAS, UCLA, ASES, and Constant–Murley scores improved from 5 ± 2.45, 15.67 ± 3.44, 47.67 ± 17.41 and 49.17 ± 8.98 preoperatively, to 0.83 ± 0.75, 36.27 ± 3.83, 91.67 ± 10.76 and 85.83 ± 4.31 at the final follow‐up, with statistical significances of P = 0.009, P < 0.001, P = 0.006, and P = 0.001, respectively. Meanwhile, the active shoulder ROM (forward flexion and abduction) improved from 135.00 ± 46.80 and 125 ± 56.48 preoperatively, to 173.67 ± 4.13 and 172 ± 3.27 at final follow‐up, respectively (P = 0.082, P = 0.088). During the follow‐up, there were no postoperative complications such as wound‐site infection, nerve or vessel damage, subcutaneous hematoma, and suture anchor problems.

Conclusion

With the benefit of reducing the possibility of strangulation and blood supply affection for the rotator cuff, The H‐loop knotless double row technique may be an alternative method to significantly improve subjective functional outcomes and increase the healing rate of medium‐sized rotator cuff tears with degeneration issues and poor tissue quality.

Repair Integrity and Functional Outcomes Between Knot-Tying and Knotless Suture-Bridge Arthroscopic Rotator Cuff Repair: A Prospective Randomized Clinical Trial

Background:

Knot-tying suture-bridge (SB) rotator cuff repair may compromise the vascularity of the repaired tendon, causing tendon strangulation and medial repair failure. The knotless SB repair technique has been proposed to overcome this possibility and decrease retear rates.

Purpose:

To compare clinical and structural outcomes and retear patterns between the knot-tying and knotless SB techniques. We hypothesized that the knotless technique would result in lower retear rates owing to the preservation of intratendinous vascularity.

Study Design:

Randomized controlled trial; Level of evidence, 1.

Methods:

A total of 104 patients with full-thickness rotator cuff tears were randomly and prospectively allocated to undergo knot-tying (group 1) or knotless (group 2) SB repair. Clinical outcome measures included range of motion, the visual analog scale (VAS) for pain, and the Constant score for function. Repair integrity was evaluated on magnetic resonance imaging scans using the Sugaya classification. Retears were also classified according to their pattern as type 1 (lateral) or type 2 (medial).

Results:

Overall, 88 patients (group 1: n = 42 [mean ± SD age, 54.3 ± 9.8 years]; group 2: n = 46 [mean ± SD age, 55.8 ± 8.2 years]) were included in the final analysis. The mean ± SD follow-up period was 25.4 ± 8.3 and 23.3 ± 7.2 months for groups 1 and 2, respectively. From preoperatively to postoperatively, the mean VAS pain score improved significantly in both groups (group 1: from 7.4 ± 1.7 to 1.0 ± 1.7; group 2: from 7.1 ± 1.9 to 1.3 ± 2.0; P < .0001 for both), as did the mean ± SD Constant score (group 1: from 51.7 ± 13.4 to 86.0 ± 11.5; group 2: from 49.4 ± 18.4 to 87.2 ± 14.8; P < .0001 for both). There was no significant difference between the groups for the postoperative VAS or Constant score. The retear rate was not significantly different between the groups (19.0% [8/42] in group 1 and 28.3% [13/46] in group 2; P > .05). There was a significant difference in the type 2 failure rate (75.0% [6/8] in group 1 and 23.1% [3/13] in group 2; P = .03).

Conclusion:

Both techniques showed excellent improvement and comparable clinical outcomes, and there was no significant difference in retear rates. Consistent with previously published data, the type 2 failure rate was significantly higher with the knot-tying technique.

Registration:

NCT03982108 (ClinicalTrials.gov identifier).

Outcomes of the Star Repair for Large and Massive Rotator Cuff Tears: A Modified Triple-Row Technique

Background:

Large and massive rotator cuff repairs constitute a true challenge for arthroscopic shoulder surgeons. Retear rates as high as 20% have been reported after arthroscopic double-row and suture-bridge techniques used for these tears.

Hypothesis:

A modified triple-row repair will provide satisfactory clinical results with lower risk for retear.

Study Design:

Case series; Level of evidence, 4.

Methods:

Between March 2016 and August 2017, a total of 52 patients with large and massive rotator cuff tears received a modified triple-row cuff repair. A middle repositioning anchor was inserted between the medial and the lateral rows. The middle anchor sutures were loaded to lateral knotless anchors in a star-shaped configuration. Functional evaluation was performed using the American Shoulder and Elbow Surgeons score, University of California, Los Angeles score, Constant-Murley score, and Simple Shoulder Test. Subjective evaluation was carried out using a visual analog scale for pain and a subjective shoulder value score. Health-related as well as disease-specific quality-of-life scores were also used. Retear rates were assessed by means of musculoskeletal ultrasonography. Patients were evaluated for a minimum of 24 months.

Results:

This study included 34 female and 18 male patients with a mean age of 57.17 ± 6.7 years. There were 35 patients (67.3%) with large tears and 17 patients (32.7%) with massive tears. Significant improvement from preoperative values was seen in all functional and subjective scores (P < .001). The mean forward flexion was 163° ± 9.7°, and the mean lateral abduction was 159.4° ± 9.4°. All patients had excellent scores on the general health-related and disease-specific quality-of-life scales. No retears were reported at the end of the follow-up period.

Conclusion:

The star-shaped, modified triple-row cuff repair is a valid and effective solution for surgical management of large and massive rotator cuff tears, providing excellent results and low risk for retears.

Arthroscopic Knotless-Anchor Rotator Cuff Repair

The most common type of rotator cuff lesion is a tear of the supraspinatus tendon, with arthroscopic rotator cuff repair representing an established treatment option^1-3. Several double-row techniques have been described to achieve complete coverage of the rotator cuff footprint. Among these is the bridging, double-row, transosseous-equivalent rotator cuff repair, which has become one of the most popular techniques for its maximized contact area and initial fixation strength^4-9. However, medial cuff failure is a common complication following this procedure^9-14. To reduce medial strangulation and overall surgical time, all-knotless anchor repair has been introduced as an alternative technique¹⁵. The arthroscopic knotless, bridging, double-row, transosseous-equivalent technique is performed with the patient in the beach-chair position via lateral operative and viewing portals. A medial row of suture anchors is placed in the usual fashion. The tendon is then perforated twice per anchor with use of a suture-passer device, after which the suture limbs are bridged over the tendon and fixed in a lateral row of anchors. Excellent functional outcomes as well as satisfaction in >90% of patients have been reported with the supraspinatus knotted double-row, bridging, transosseous-equivalent repair^{4,9,11,13,16-19}. No significant differences have been reported for clinical results and tendon integrity on magnetic resonance imaging when comparing knot-tying and knotless double-row transosseous-equivalent rotator cuff repair; however, the rate of medial cuff failure was lower among knotless procedures^{1,12,16,17,20-25}. The major steps of the procedure, which are demonstrated in this video article, include (1) diagnostic arthroscopy; (2) supraspinatus tear visualization and debridement; (3) decortication of the footprint on the greater tuberosity; (4) placement of the medial row of anchors loaded with nonabsorbable suture tape; (5) separate suture passage of each limb, perforating the tendon with use of a suture passer; (6) fixation of the tape in the lateral row of anchors, creating a bridging configuration; and (7) anterolateral acromioplasty with use of an arthroscopic burr. Complications are rare following this procedure. As postoperative rehabilitation is essential for tendon healing, the operative arm should be placed in an abduction brace for 6 weeks, with only passive mobilization.

Repair Integrity and Retear Pattern After Arthroscopic Medial Knot-Tying After Suture-Bridge Lateral Row Rotator Cuff Repair

BACKGROUND

Type 2 failure is a big issue after suture-bridge rotator cuff repair, which may be because of stress concentration at the medial row stitches. We have been performing medial knot-tying after suture-bridge lateral row repair to avoid the stress concentration. This study aimed to evaluate clinical and radiological outcomes after arthroscopic rotator cuff repair using this technique.

HYPOTHESIS

This technique would yield better radiological outcomes with a reduced type 2 failure rate compared with reported outcomes after conventional suture-bridge repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The inclusion criteria of this study were (1) full-thickness tears, (2) primary surgery, and (3) minimum 2-year follow-up with pre- and postoperative magnetic resonance imaging (MRI). We investigated active ranges of motion (forward elevation and external rotation), as well as the Japanese Orthopaedic Association (JOA) and University of California, Los Angeles (UCLA), scores preoperatively and at the final follow-up.

RESULTS

This study included 384 shoulders in 373 patients (205 men and 168 women) with a mean age of 65 years (range, 24-89 years) at the time of surgery. The mean follow-up was 29 months (range, 24-60 months). There were 91 small, 137 medium, 121 large, and 35 massive tears. Postoperative MRI scans demonstrated successful repair in 324 shoulders (84.4%, group S) and retear in 60 shoulders (15.6%). Among 60 retears, 40 shoulders (67%) had type 1 failure (group F1) and 20 shoulders (33%) had type 2 failure (group F2). Forward elevation and external rotation significantly improved after surgery (P < .001 for both). Postoperative JOA and UCLA scores in group F2 were significantly lower than those in the other groups.

CONCLUSION

The medial knot-tying after suture-bridge lateral row repair demonstrated excellent functional and radiological outcomes after surgery, with a retear rate of 15.6%. The type 2 failure showed significantly inferior functional outcomes; however, the rate of type 2 failure was less relative to previous studies using conventional suture-bridge techniques. Our technique could be a good alternative to conventional suture-bridging rotator cuff repair because it may reduce the rate of postoperative type 2 failure.

Optimizing the Double-Row Construct: An Untied Medial Row Demonstrates Equivalent Mean Contact Pressures in a Rotator Cuff Model

Background:

The merits of a double-row rotator cuff repair (RCR) construct are well-established for restoration of the footprint and lateral-row security. The theoretical benefit of leaving the medial row untied is to prevent damage to the rotator cuff by tissue strangulation, and the benefit of suture tape is a more even distribution of force across the repair site. These benefits, to our knowledge, have not been evaluated in the laboratory.

Hypothesis:

Leaving the medial row untied and using a suture bridge technique with suture tape will offer more even pressure distribution across the repair site without compromising total contact force.

Study Design:

Controlled laboratory study.

Methods:

A laboratory model of RCR was created using biomechanical research-grade composite humeri and human dermal allografts. The pressure distribution in a double-row suture bridge repair construct was analyzed using the following testing matrix: double-loaded suture anchors with the medial row tied (n = 15) versus untied (n = 15) compared with double-loaded suture tape and anchors with the medial row tied (n = 15) versus untied (n = 15). A digital pressure sensor was used to measure pressure over time after tensioning of the repair site. A multivariate analysis of variance was used for statistical analysis with post hoc testing.

Results:

The total contact force did not significantly differ between constructs. The contact force between double-loaded suture anchors and double-loaded suture tape and anchors was similar when tied (P = .15) and untied (P = .44). An untied medial row resulted in similar contact forces in both the double-loaded suture anchor (P = .16) and double-loaded suture tape and anchor (P = .25) constructs. Qualitative increases in focal contact pressure were seen when the medial row was tied.

Conclusion:

An untied medial row did not significantly affect the total contact force with double-loaded suture anchors and with double-loaded suture tape and anchors. Tying the medial row qualitatively increased crimping at the construct’s periphery, which may contribute to tissue strangulation and hinder clinical healing. Qualitative improvements in force distribution were seen with double-loaded suture tape and anchors.

Clinical Relevance:

Both tied and untied medial rows demonstrated similar pressures across the repair construct.

Is it necessary to tie the medial row in rotator cuff repair double-row constructs when using suture tape?

PURPOSE

To evaluate the selected biomechanical differences of a double-row trans-osseous equivalent rotator cuff repair with a knotless versus knot-tying medial row using suture tape in regard to repair displacement, stiffness, and ultimate load to failure.

METHODS

In 16 fresh-frozen human shoulders (8 matched pairs), double-row rotator cuff repairs were performed with medial-row mattress knots (MK) on one side, the other without (NK). Two DVRT (Differential Variable Reluctance Transducer) sensors were attached between the humerus and 3 mm above the repair site and were used to measure the displacement across the repair during cycling. The biomechanical parameters measured were repair displacement, stiffness, and ultimate load to failure. The supraspinatus was loaded in a similar fashion to previously described protocol using cyclic loading and load to failure testing.¹.

RESULTS

All data from paired specimens were compared using paired Student t tests. No statistically significant difference (SSD) in displacement across the repair over the 200 cycles of the test was noted between the two groups (MK = 0.591 ± 0.501 mm; NK = 0.439 ± 0.417 mm, p = 0.618). No SSD in stiffness was noted between the two groups (MK = 32.87 ± 6.31 N/mm; NK = 27.98 ± 9.69 N/mm, p = 0.120). No SSD in ultimate load to failure was noted between the two groups (MK = 501.2 ± 126.1 N; NK = 416.8 ± 120.0 N, p = 0.116).

CONCLUSION

There was no statistically significant different between knotless versus knotted medial row double row rotator cuff repair constructs using suture tape in regard to displacement across the repair site, stiffness and ultimate load to failure. Despite previous evidence suggesting inferiority of knotless medial row technique using suture constructs, this evidence may support the biomechanical equivalency of knotless medial row technique using suture tape.

A Prospective Randomized Trial Comparing Suture Bridge and Medially Based Single-Row Rotator Cuff Repair in Medium-Sized Supraspinatus Tears

PURPOSE

To compare the clinical and imaging outcomes between the suture bridge technique (SB) and the medially based single-row technique (medSR) in patients with 1- to 3-cm tear sizes.

METHODS

All patients were evaluated preoperatively and postoperatively (at 12 and 24 months) using the modified University of California, Los Angeles scoring system; active range of motion (flexion and external rotation); and a visual analog scale for pain. Healing status was examined by postoperative magnetic resonance imaging.

RESULTS

Clinical and imaging evaluations were completed by 92 patients at 1-year follow-up and by 74 patients at 2 years. No significant differences were found between the 2 groups across all measures at final follow-up: The University of California, Los Angeles scores were 33.4 points in SB patients and 33.0 points in medSR patients (P = .58); the visual analog scale scores were 6 mm and 7 mm, respectively (P = .38); the active flexion angles were 161° and 159°, respectively (P = .34); and the external rotation angles were 49° and 52°, respectively (P = .37). Retears were observed in 6.5% of SB patients and 2.1% of medSR patients (P = .31). Medial cuff failure was observed only in SB patients (4.3%, 2 cases), whereas incomplete healing (deep-layer retraction pattern) was observed only in medSR patients (8.7%, 4 cases). Neo-tendon regeneration in the medSR group was observed in 93% of patients.

CONCLUSIONS

This study did not show any significant differences in the clinical outcomes and cuff integrity between the 2 treatment groups at final follow-up; however, medial cuff failure was observed only in the SB group, and incomplete healing was more frequent in the medSR group. One should consider the risk of medial cuff failure and incomplete healing of the repaired cuff before choosing the repair technique for medium-sized supraspinatus tears.

LEVEL OF EVIDENCE

Level I, therapeutic, prospective, randomized trial.

Arthroscopic Rotator Cuff Repair in 2019: Linked, Double Row Repair for Achieving Higher Healing Rates and Optimal Clinical Outcomes

The primary aim of rotator cuff repair surgery is to restore the musculotendinous units by creating a complete, tension-free repair construct that optimizes conditions for tendon-to-bone healing. There are many factors outside the control of the surgeon that are capable of affecting the healing process; however, there are also a number of important technical considerations that the surgeon can control, including familiarity with methods to deal with immobile tissues and techniques to perform novel repair constructs. It is clear that linked double row repairs are more likely to heal, and healed rotator cuff repairs best restore shoulder strength, improve patients' satisfaction, and maximize functional outcomes.

Does Medial-Row Fixation Technique Affect the Retear Rate and Functional Outcomes After Double-Row Transosseous-Equivalent Rotator Cuff Repair?

Background:

Double-row transosseous-equivalent (TOE) rotator cuff repair techniques have been widely accepted because of their superior biomechanical properties when compared with arthroscopic single-row repair. Concerns regarding repair overtensioning with medial-row knot tying have led to increased interest in knotless repair techniques; however, there is a paucity of clinical data to guide the choice of technique.

Hypothesis:

Arthroscopic TOE repair techniques using knotless medial-row fixation will demonstrate lower retear rates and greater improvements in the Constant score relative to conventional knot-tying TOE techniques.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review of 3 databases (PubMed, Cochrane, and Embase) was performed using PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) guidelines. Inclusion criteria were English-language studies that examined repair integrity or Constant scores after arthroscopic rotator cuff repair with TOE techniques. Two investigators independently screened results for relevant articles. Data regarding the study design, surgical technique, retear rate, and Constant shoulder score were extracted from eligible studies. A quality assessment of all articles was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

Results:

The systematic review identified a total of 32 studies (level of evidence, 1-4) that met inclusion and exclusion criteria. Of the 32 studies, 5 reported on knotless TOE techniques, 25 reported on knot-tying TOE techniques, and 2 reported on both. In the knotless group, retear rates ranged from 6% to 36%, and Constant scores ranged from 38-65 (preoperative) to 73-83 (postoperative). In the knot-tying group, retear rates ranged from 0% to 48%, and Constant scores ranged from 42-64 (preoperative) to 55-96 (postoperative).

Conclusion:

Despite several theoretical advantages of knotless TOE repair, both knotless and knot-tying techniques reported considerable improvement in functional outcomes after rotator cuff repair. Although tendon failure rates showed a downward trend in knotless studies, additional prospective studies are warranted to better understand the role of medial-row fixation on tendon repair integrity and postoperative clinical outcomes.

Arthroscopic double-row rotator cuff repair: a comprehensive review of the literature

Rotator cuff repairs seek to achieve adequate tendon fixation and to secure the fixation during the process of biological healing. Currently, arthroscopic rotator cuff repair has become the gold standard. One of the earliest defined techniques is single-row repair but the inadequacy of single-row repair to precisely restore the anatomical footprint as well as the significant rates of retear especially in large tears have led surgeons to seek other techniques. Double-row repair techniques, which have been developed in response to these concerns, have various modifications like the number and placement of anchors and suture configurations.

When the literature is reviewed, it is possible to say that double-row repairs demonstrate superior biomechanical properties. In regard to retear rates, both double row and transosseous equivalent (TOE) techniques have also yielded more favorable outcomes compared to single-row repair. But the clinical results are conflicting and more studies have to be conducted. However, it is more probable that superior structural integrity will yield better structural and functional results in the long run. TOE repair technique is regarded as promising in terms of better biomechanics and healing since it provides better footprint contact. Knotless TOE structures are believed to reduce impingement on the medial side of tendons and thus aid in tendon nutrition; however, there are not enough studies about its effectiveness.

It is important to optimize the costs without endangering the treatment of the patients. We believe that the arthroscopic TOE repair technique will yield superior results in regard to both repair integrity and functionality, especially with tears larger than 3 cm. Although defining the pattern of the tear is one of the most important guiding steps when selecting the repair technique, the surgeon should not forget to evaluate every patient individually for tendon healing capacity and functional expectations.

Effect of structural design on the pullout strength of suture anchors for rotator cuff repair

Various types of suture anchor designs are currently available for rotator cuff repair. The purpose of our study was to investigate the pullout strength of such anchors based on their structural design and the predominant geometric design factors affecting the pullout strength using finite element analysis. Finite element models were constructed using five cadaveric humeri and ten suture anchors with different designs. The pullout strength and distribution of bone stress around the anchor at three different directions of the applied force (0°, 45°, and 75°) were analyzed. The following geometric factors of suture anchor design were computed and their correlations with pullout strength assessed: Overall length, minor, and major diameters; number of threads; height of thread; distance between threads; helix angle; contact surface area between the anchor threads and surrounding bone; contact surface area between the cylindrical portion of the anchor; and surrounding bone and total contact surface area between the anchor and surrounding bone. The pullout strength and distribution of bone stress around the anchor varied according to the suture anchor designs and the direction of the applied force, respectively. The pullout strength had a strong positive correlation with the contact surface area between the anchor threads and surrounding bone, overall length, and the number and height of threads. This study demonstrated that suture anchor designs with increased contact surface area between the anchor threads and surrounding bone, overall length, and the number and height of threads can enhance the pullout strength during rotator cuff repair. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:3318-3327, 2018.

Type 2 retear after arthroscopic single-row, double-row and suture bridge rotator cuff repair: a systematic review

AIM/PURPOSE

To provide a systematic review of the literature on patterns of retear after single-row (SR), double-row (DR) and suture bridge (SB) techniques.

METHODS

The PubMed and MEDLINE databases were searched for published articles reporting both repair technique and retear pattern. Studies in languages other than English, those reporting open rotator cuff repair as the index procedure, as well as animal and cadaveric studies and those which did not describe patterns of retear, were excluded. MINORS scoring system was used to quantify potential bias in each study. Retears were classified into type 1 (failure at the tendon-bone interface) and type 2 (medial cuff failure). For all studies included, number and type of retears after different repair techniques were reported and analyzed.

RESULTS

Fourteen studies were included yielding a total of 260 rotator cuff retears. Repair technique had a significant impact on the estimated incidence rate of type 2 retear (p = .001). The estimated incidence rate of type 2 retear was 24% with SR (95% CI 14-38%), 43% with DR (95% CI 22-66%), 62% with SB (95% CI 54-70%) and 38% with SB (95% CI 23-57%).

CONCLUSION

Despite the lack of high-quality evidence, this study suggests that DR and SB techniques increase the risk of medial cuff failure. Modifications in surgical techniques in both DR and SB repairs can help decrease that risk.

LEVEL OF EVIDENCE

Level IV, systematic review of investigations including level IV.

Clinical outcomes and repair integrity of arthroscopic rotator cuff repair using suture-bridge technique with or without medial tying: prospective comparative study

Background

There have been few studies comparing clinical and radiological outcomes between the conventional and knotless suture-bridge techniques. The purpose of this study was to evaluate and compare the functional outcomes and repair integrity of arthroscopic conventional and knotless suture-bridge technique for full-thickness rotator cuff tears.

Methods

We prospectively followed 100 consecutive patients (100 shoulders) with full-thickness rotator cuff tears treated with the arthroscopic conventional or knotless suture-bridge technique from October 2012 to July 2014. Enrolled patients returned for follow-up functional evaluations at 1 and 2 years after the operation. There were four outcome measures in this study: American Shoulder and Elbow Surgeons (ASES) scores, Shoulder Rating Scale of the University of California at Los Angeles (UCLA) scores, Constant scores, and visual analog scale (VAS) pain scores. Enrolled patients returned for follow-up magnetic resonance imaging or ultrasonography evaluation to confirm the integrity of the repaired cuff at 6 months post-operation (97% follow-up rate). Also, we investigated the preoperative cuff retraction of enrolled patients using preoperative MRI to find out correlation between the stage of cuff retraction and re-tear rate.

Results

At final follow-up, the average UCLA, ASES, Constant, and VAS scores had improved significantly to 32.5, 88.0, 80.4, and 1.3, respectively, in the conventional suture-bridge technique group and to 33.0, 89.7, 81.2, and 1.2, respectively, in the knotless suture-bridge technique group. The UCLA, ASES, Constant, and VAS scores improved in both groups after surgery (all p < 0.001), and there were no significant differences between the two groups at 2-year follow-up (p = 0.292, 0.359, 0.709, and 0.636, respectively). The re-tear rate of repaired rotator cuffs was 16.3% (8/49 shoulders) in the conventional suture-bridge technique group and 29.2% (14/48 shoulders) in the knotless suture-bridge technique group; this difference was not significant (p = 0.131). There were no significant differences between the re-tear rate of the two groups in the Patte stage I and II (p = 0.358 and 0.616).

Conclusions

The knotless suture-bridge technique showed comparable functional outcomes to those of conventional suture-bridge techniques in medium-to-large, full-thickness rotator cuff tears at short-term follow-up. The knotless suture-bridge technique had a higher re-tear rate compared with conventional suture-bridge technique, although the difference was not significant.

Recurrent tears of the rotator cuff: Effect of repair technique and management options

Retears of the rotator cuff, following operative repair, is not an uncommon event. Various factors have been shown to influence recurrence including the technique of repair. Multiple techniques have been performed with varying results and complications. The repair technique significantly affects the rate and pattern of retears. Although risk of retears with double row and suture bridge techniques is relatively low, medial cuff failure is a potential complication which poses significant challenges when revision repair is undertaken. Modifications in surgical techniques in, both, double row and suture bridge repairs can help decrease the risk of medial cuff failure. Thorough analysis of retear rates and patterns reported, and their relation with the repair technique, provides new insights about the pathogenesis of rotator cuff retears, their future prevention and appropriate management.

[Arthroscopic rotator cuff surgery : New and established methods]

This present article summarizes established and current developments and aspects of rotator cuff surgery. Achieved milestones as well as current approaches are presented and assessed with respect to their clinical and radiographic impact. Despite biomechanical and technical improvements in modern rotator cuff repair techniques, re-defect and re-tearing rates could not be fully eliminated. Meanwhile, the importance of biological processes around successful tendon-bone reintegration has been increasingly recognized. Hence, this article presents the current scientific standing regarding biological growth factors, platelet-rich plasma and rotator cuff augmentation techniques (with allogenic/autologous grafts). In summary, there are clear biomechanical advantages as well as many promising approaches to biological augmentation; however, the latter have not yet been transferred into regular clinical application.

Arthroscopic Repair of Medial Transtendinous Rotator Cuff Tears

Rotator cuff tears are extremely common in the adult population, and medial transtendinous rotator cuff tears, although rare, have recently been reported in the literature. These tears are almost always traumatic, which is a common indication for surgical management. It is necessary to consider these tears as a distinct subset when planning for rotator cuff repair because traditional repair techniques would overtension the tendon, increasing the risk for failure of the repair. The objective of this Technical Note is to describe an arthroscopic repair technique for these tears that avoids overtensioning the rotator cuff while still using repair techniques that are familiar to the arthroscopic shoulder surgeon.

Predictors of outcomes after arthroscopic transosseous equivalent rotator cuff repair in 155 cases: a propensity score weighted analysis of knotted and knotless self-reinforcing repair techniques at a minimum of 2 years

PURPOSE

To evaluate the outcomes of two commonly used transosseous-equivalent (TOE) arthroscopic rotator cuff repair (RCR) techniques for full-thickness supraspinatus tendon tears (FTST) using a robust multi-predictor model.

METHODS

155 shoulders in 151 patients (109 men, 42 women; mean age 59 ± 10 years) who underwent arthroscopic RCR of FTST, using either a knotted suture bridging (KSB) or a knotless tape bridging (KTB) TOE technique were included. ASES and SF-12 PCS scores assessed at a minimum of 2 years postoperatively were modeled using propensity score weighting in a multiple linear regression model. Patients able to return to the study center underwent a follow-up MRI for evaluation of rotator cuff integrity.

RESULTS

The outcome data were available for 137 shoulders (88%; n = 35/41 KSB; n = 102/114 KTB). Seven patients (5.1%) that underwent revision rotator cuff surgery were considered failures. The median postoperative ASES score of the remaining 130 shoulders was 98 at a mean follow-up of 2.9 years (range 2.0-5.4 years). A higher preoperative baseline outcome score and a longer follow-up had a positive effect, whereas a previous RCR and workers' compensation claims (WCC) had a negative effect on final ASES or SF 12 PCS scores. The repair technique, age, gender and the number of anchors used for the RCR had no significant influence. Fifty-two patients returned for a follow-up MRI at a mean of 4.4 years postoperatively. Patients with a KSB RCR were significantly more likely to have an MRI-diagnosed full-thickness rotator cuff re-tear (p < 0.05).

CONCLUSIONS

Excellent outcomes can be achieved at a minimum of 2 years following arthroscopic KSB or KTB TOE RCR of FTST. The preoperative baseline outcome score, a prior RCR, WCC and the length of follow-up significantly influenced the outcome scores. The repair technique did not affect the final functional outcomes, but patients with KTB TOE RCR were less likely to have a full-thickness rotator cuff re-tear.

LEVEL OF EVIDENCE

Level III, Retrospective Comparative Study.

Rotator Cuff Tears at the Musculotendinous Junction: Classification and Surgical Options for Repair and Reconstruction

Although uncommon, rotator cuff tears that occur medially at the musculotendinous junction can result from acute trauma, anatomic force imbalance, or medial row cuff failure following a previous rotator cuff repair. The quality of the torn muscle and tendon along with the length of the remnant tendon stump should be considered before deciding on the most appropriate repair technique. When muscle and tendon quality are sufficient, the tear can often be repaired directly to the remnant tendon stump and compressed onto the greater tuberosity. If the remnant tendon stump is degenerative, of insufficient length, or lacks tendon in which to place sutures, an allograft patch can be used to augment the repair. When the quality of the remaining muscle and tendon are poor or when the muscle is retracted too far medially and is nonmobile, a bridging technique such as superior capsule reconstruction is preferable. The purpose of this report is to (1) highlight that medial cuff failure can occur both primarily and after previous repair; (2) define and classify the 3 major tear patterns that are encountered, and (3) describe the authors' preferred techniques for medial cuff repair that specifically address each of the major tear patterns.

Tight medial knot tying may increase retearing risk after transosseous equivalent repair of rotator cuff tendon

BACKGROUND

Retearing mechanism after transosseous equivalent (TOE) rotator cuff repair has not been fully clarified yet.

OBJECTIVE

The purposes of this study were to compare the stress distribution pattern in the tendon stump between knotted and knotless TOE repair and to investigate the role of suture tension applied during medial knot tying using a 3-dimensional finite element (3D-FE) method.

METHODS

Both knotted and knotless TOE repairs were simulated on the 3D-FE human rotator cuff tear model. Elastic analysis was performed to compare the stress distribution pattern inside the tendon between the two models. The amount of compressive load applied to the medial-row sutures was then changed as 0, 20, 40, 60, 80, and 100 N in the knotted model.

RESULTS

Knotted model demonstrated more distinct stress concentration inside the tendon around medial-row sutures than the knotless model. Mean von Mises equivalent stress in this area in the 0, 20, 40, 60, 80, and 100 N models was 0.26, 0.35, 0.50, 0.70, 1.11, and 1.14 MPa, respectively.

CONCLUSIONS

In the knotted TOE repair, tight medial knot tying might cause a high stress concentration around medial knots, which may constitute one of the pathogenetic factors of postoperative retearing at this site.

Perfusion of the Rotator Cuff Tendon According to the Repair Configuration Using an Indocyanine Green Fluorescence Arthroscope: A Preliminary Report

BACKGROUND

The disturbance of rotator cuff tendon perfusion has been connected with the suture-bridge configuration repair (SBCR) technique; however, in vivo assessments of the tendon blood supply have been problematic with other modalities. An evaluation of tissue perfusion by an indocyanine green (ICG) fluorescence arthroscope has been developed to counteract this difficulty.

PURPOSE

To verify the hindrance of perfusion in SBCR, we used an ICG fluorescence camera to compare parallel-type transosseous repair (PTR) and SBCR in rabbits immediately and at 3 days after rotator cuff repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Acute rotator cuff repair was performed on the shoulders of 10 rabbits. Both shoulders were repaired using either PTR or SBCR. For PTR, simple repair was performed through 2 parallel transosseous tunnels created using a microdrill. For SBCR, 2 additional crisscross transosseous tunnels were added to mimic arthroscopic SBCR. Immediately after repair, ICG was injected through the ear vein, and images were recorded using an ICG fluorescence camera. Tendon perfusion was compared by measuring fluorescence intensity using ImageJ software in both methods. At 3 days after rotator cuff repair, a reassessment of ICG fluorescence was performed. In addition, as a subsidiary study, a comparison of each repair method and a healthy tendon was performed (PTR vs healthy tendon and SBCR vs healthy tendon). Six rabbits (3 for each comparison) were included.

RESULTS

Immediately after rotator cuff repair, the mean (±SD) grayscale intensity of ICG fluorescence was weaker in SBCR than PTR in 10 specimens (65.9 ± 47.6 vs 84.3 ± 53.4 per pixel, respectively; P = .003). At 3 days after repair, 8 specimens were included in the analysis because suture strands failed in 2 specimens in SBCR. The mean intensity of fluorescence was still weaker in SBCR compared with PTR (52.5 ± 13.7 vs 60.2 ± 22.7 per pixel, respectively; P = .077). The mean fluorescence intensity compared with a healthy tendon was 83.2% ± 9.5% in PTR and 63.2% ± 13.2% in SBCR.

CONCLUSION

Our ICG fluorescence camera system was able to detect ICG fluorescence in an acute rabbit rotator cuff repair model. SBCR showed inferior tendon perfusion immediately after repair. At 3 days after repair, SBCR still showed inferior fluorescence intensity, although it did not reach statistical significance.

CLINICAL RELEVANCE

In this study, SBCR hindered perfusion at the tendon in the compressed area. This finding may affect rotator cuff tendon healing and failure mode.

Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair

PURPOSE

To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model.

METHODS

A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system.

RESULTS

The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing.

CONCLUSIONS

In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure.

CLINICAL RELEVANCE

In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure.

Traumatic full-thickness transtendinous rotator cuff tears: a case series

HYPOTHESIS

Our purpose was to describe an arthroscopic repair technique for and outcomes of traumatic transtendinous rotator cuff tears affecting the supraspinatus tendon.

MATERIALS AND METHODS

A retrospective review was performed on a series of patients between January 2009 and January 2012. Demographic data, as well as preoperative and postoperative clinical data including strength, visual analog scale pain score, Subjective Shoulder Value, American Shoulder and Elbow Surgeons score, and Simple Shoulder Test score, were obtained.

RESULTS

Seven patients were identified with magnetic resonance imaging showing full-thickness, transtendon supraspinatus tears with extension into the infraspinatus, which were consistent with physical examination and arthroscopic findings. The mechanism of injury was traumatic in all cases, usually a fall with the arm abducted. The mean remaining stump of tendon measured 1.3 cm. All patients underwent open or arthroscopic repair by a side-to-side (tendon-to-tendon) technique with additional suture anchor augmentation. At an average follow-up of 41.5 months (range, 33-50 months), all patients had postoperative improvements in strength and visual analog scale pain scores (range, 0-1), as well as Subjective Shoulder Value, Simple Shoulder Test, and American Shoulder and Elbow Surgeons scores greater than 90.

CONCLUSION

We have described the occurrence of a rare rotator cuff tear in the purely tendinous portion of the muscle, leaving at least 1 cm of tendon attached to an intact footprint. We also have presented an arthroscopic side-to-side repair technique and postoperative outcomes. To our knowledge, this is the first article describing this uncommon rotator cuff tear.

[Rotator cuff repair: single- vs double-row. Clinical and biomechanical results]

BACKGROUND

The goal of rotator cuff repair is a high initial mechanical stability as a requirement for adequate biological recovery of the tendon-to-bone complex. Notwithstanding the significant increase in publications concerning the topic of rotator cuff repair, there are still controversies regarding surgical technique.

OBJECTIVES

The aim of this work is to present an overview of the recently published results of biomechanical and clinical studies on rotator cuff repair using single- and double-row techniques.

MATERIALS AND METHODS

The review is based on a selective literature research of PubMed, Embase, and the Cochrane Database on the subject of the clinical and biomechanical results of single- and double-row repair.

RESULTS

In general, neither the biomechanical nor the clinical evidence can recommend the use of a double-row concept for the treatment for every rotator cuff tear. Only tears of more than 3 cm seem to benefit from better results on both imaging and in clinical outcome studies compared with the use of single-row techniques.

CONCLUSIONS

Despite a significant increase in publications on the surgical treatment of rotator cuff tears in recent years, the clinical results were not significantly improved in the literature so far. Unique information and algorithms, from which the optimal treatment of this entity can be derived, are still inadequate. Because of the cost-effectiveness and the currently vague evidence, the double-row techniques cannot be generally recommended for the repair of all rotator cuff tears.

Biomechanical Comparison of Modified Suture Bridge Using Rip-Stop versus Traditional Suture Bridge for Rotator Cuff Repair

Purpose. To compare the biomechanical properties of 3 suture-bridge techniques for rotator cuff repair. Methods. Twelve pair-matched fresh-frozen shoulder specimens were randomized to 3 groups of different repair types: the medially Knotted Suture Bridge (KSB), the medially Untied Suture Bridge (USB), and the Modified Suture Bridge (MSB). Cyclic loading and load-to-failure test were performed. Parameters of elongation, stiffness, load at failure, and mode of failure were recorded. Results. The MSB technique had the significantly greatest load to failure (515.6 ± 78.0 N, P = 0.04 for KSB group; P < 0.001 for USB group), stiffness (58.0 ± 10.7 N/mm, P = 0.005 for KSB group; P < 0.001 for USB group), and lowest elongation (1.49 ± 0.39 mm, P = 0.009 for KSB group; P = 0.001 for USB group) among 3 groups. The KSB repair had significantly higher ultimate load (443.5 ± 65.0 N) than USB repair (363.5 ± 52.3 N, P = 0.024). However, there was no statistical difference in stiffness and elongation between KSB and USB technique (P = 0.396 for stiffness and P = 0.242 for elongation, resp.). The failure mode for all specimens was suture pulling through the cuff tendon. Conclusions. Our modified suture bridge technique (MSB) may provide enhanced biomechanical properties when compared with medially knotted or knotless repair. Clinical Relevance. Our modified technique may represent a promising alternative in arthroscopic rotator cuff repair.

The Medial Stitch in Transosseous-Equivalent Rotator Cuff Repair: Vertical or Horizontal Mattress?

BACKGROUND

Despite advances in surgical technique, rotator cuff repair retears continue to occur at rates of 10%, 22%, and 57% for small, medium, and large tears, respectively. A common mode of failure in transosseous-equivalent rotator cuff repairs is tissue pullout of the medial mattress stitch. While the medial mattress stitch has been studied extensively, no studies have evaluated a vertical mattress pattern placed near the musculotendinous junction in comparison with a horizontal mattress pattern.

HYPOTHESIS

Vertical mattress stitches will have higher load to failure and lower gapping compared with horizontal mattress stitches in a transosseous-equivalent rotator cuff repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Double-row transosseous-equivalent rotator cuff repairs were performed in 9 pairs of human male cadaveric shoulders (mean age ± SD, 58 ± 10 years). One shoulder in each pair received a medial-row suture pattern using a vertical mattress stitch, and the contralateral shoulder received a horizontal mattress. Specimens were mounted in a materials testing machine and tested in uniaxial tensile deformation for cyclic loading (500 cycles at 1 Hz to 1.0 MPa of effective stress), followed by failure testing carried out at a rate of 1 mm/s. Construct gapping and applied loads were monitored continuously throughout the testing.

RESULTS

Vertical mattress sutures were placed in 5 right and 4 left shoulders. Peak cyclic gapping did not differ between vertical (mean ± SD, 2.8 ± 1.1 mm) and horizontal mattress specimens (3.0 ± 1.2 mm) (P = .684). Vertical mattress sutures failed at higher loads compared with horizontal mattress sutures (568.9 ± 140.3 vs 451.1 ± 174.3 N; P = .025); however, there was no significant difference in failure displacement (8.0 ± 1.6 vs 6.0 ± 2.1 mm; P = .092). Failure stiffness did not differ between the suture patterns (P = .204).

CONCLUSION

In transosseous-equivalent rotator cuff repairs near the musculotendinous junction, a vertical mattress suture used as the medial stitch has a higher load to failure but no difference in gapping compared with a horizontal mattress pattern.

CLINICAL RELEVANCE

A vertical mattress suture may offer enhanced strength of repair for transosseous-equivalent repairs.

Serial MRI evaluation following arthroscopic rotator cuff repair in double-row technique

INTRODUCTION

So far, recurrent rotator cuff defects are described to occur in the early postoperative period after arthroscopic repair. The aim of this study was to evaluate the musculotendinous structure of the supraspinatus, as well as bone marrow edema or osteolysis after arthroscopic double-row repair. Therefore, magnetic resonance (MR) images were performed at defined intervals up to 2 years postoperatively.

STUDY DESIGN

Case series; Level of evidence, 3.

MATERIALS AND METHODS

MR imaging was performed within 7 days, 3, 6, 12, 26, 52 and 108 weeks after surgery. All patients were operated using an arthroscopic modified suture bridge technique. Tendon integrity, tendon retraction ["foot-print-coverage" (FPC)], muscular atrophy and fatty infiltration (signal intensity analysis) were measured at all time points. Furthermore, postoperative bone marrow edema and signs of osteolysis were assessed.

RESULTS

MR images of 13 non-consecutive patients (6f/7m, ∅ age 61.05 ± 7.7 years) could be evaluated at all time points until ∅ 108 weeks postoperatively. 5/6 patients with recurrent defect at final follow-up displayed a time of failure between 12 and 24 months after surgery. Predominant mode of failure was medial cuff failures in 4/6 cases. The initial FPC increased significantly up to 2 years follow-up (p = 0.004). Evaluations of muscular atrophy or fatty infiltration were not significant different comparing the results of all time points (p > 0.05). Postoperative bone marrow edema disappeared completely at 6 months after surgery, whereas signs of osteolysis appeared at 3 months follow-up and increased to final follow-up.

CONCLUSIONS

Recurrent defects after arthroscopic reconstruction of supraspinatus tears in modified suture bridge technique seem to occur between 12 and 24 months after surgery. Serial MRI evaluation shows good muscle structure at all time points. Postoperative bone marrow edema disappears completely several months after surgery. Signs of osteolysis seem to appear caused by bio-absorbable anchor implantations.

Healing disturbance with suture bridge configuration repair in rabbit rotator cuff tear

BACKGROUND

Medial row failure has been reported in the suture bridge technique of rotator cuff repair. This study compared the healing response of suture bridge configuration repair (SBCR) and parallel type transosseous repair (PTR).

METHODS

Acute rotator cuff repair was performed in 32 rabbits. Both shoulders were repaired using PTR or SBCR. In PTR, simple PTR was performed through 2 parallel transosseous tunnels created using a microdrill. In SBCR, 2 additional crisscross transosseous tunnels were added to mimic arthroscopic SBCR. At 1, 2, and 5 weeks postoperatively, comparative biomechanical testing was performed in 8 rabbits, and histologic analysis, including immunohistochemical staining for CD31, was performed in 4 rabbits.

RESULTS

Failure loads at 1 week (38.12 ± 20.43 N vs 52.00 ± 27.23 N; P = .284) and 5 weeks (97.93 ± 48.35 N vs 119.60 ± 60.81 N; P = .218) were not statistically different between the SBCR and PTR groups, respectively, but were significantly lower in the SBCR group than in the PTR group (23.56 ± 13.56 N vs. 44.25 ± 12.53 N; P = .009), respectively, at 2 weeks. Markedly greater fibrinoid deposition was observed in the SBCR group than in the PTR group at 2 weeks. For vascularization, there was a tendency that more vessels could be observed in PTR than in SBCR at 2 weeks (15.9 vs 5.6, P = .068).

CONCLUSIONS

In a rabbit acute rotator cuff repair model, SBCR exhibited inferior mechanical strength, and fewer blood vessels were observed at the healing site at 2 weeks postoperatively. Medial row tendon failure was more common in SBCR. Surgeons should consider the clinical effect of SBCR when performing rotator cuff repair.

Arthroscopic Knotless, Double-Row, Extended Linked Repair for Massive Rotator Cuff Tears

The management of massive rotator cuff tears remains a challenge for physicians, with failure rates being higher when compared with smaller tears. Many surgical treatment options exist including debridement with biceps tenodesis, complete repair, partial repair, repair with augmentation devices, superior capsule reconstruction, tendon transfer, and reverse total shoulder arthroplasty. The purpose of this article is to describe our preferred surgical technique for a complete arthroscopic repair using an extended linked, knotless, double-row construct.

Arthroscopic Rotator Cuff Repair With Absorbable Sutures in the Medial-Row Anchors

PURPOSE

To report the retear rate and retear pattern after double-row arthroscopic rotator cuff repair (DR-ARCR) with the use of absorbable sutures as medial anchor sutures and to address the advantage of the use of absorbable sutures in medial-row anchors.

METHODS

Fifty-seven shoulders (22 male and 35 female patients; mean age, 66.1 years) with complete rotator cuff tears treated with DR-ARCR using absorbable mattress sutures as medial-row anchor sutures were included in the study. They included 35 medium, 17 large, and 5 massive tears. For the medial row, medial anchor sutures were replaced with absorbable mattress sutures. High-strength simple sutures were used for the lateral anchors. We evaluated retear patterns by magnetic resonance imaging examinations performed at 1 month, 3 months, 6 months, and 1 year postoperatively. The clinical conditions of all patients preoperatively and 2 years postoperatively were assessed by the University of California, Los Angeles rating scale and the American Shoulder and Elbow Surgeons shoulder index.

RESULTS

A complete retear of the tendon at the footprint was observed in 5 shoulders. Complete discontinuity at the middle of the tendon around the medial-row anchors with a footprint remnant was observed in 1 shoulder. A thinned repaired rotator cuff was observed in 2 shoulders because of a partial retear of the deep layer. The overall retear rate was 14%. From before to after surgery, the University of California, Los Angeles score significantly improved from 18.4 to 32.9 (P < .0001) and the American Shoulder and Elbow Surgeons index improved from 55.1 to 87.7 (P < .0001). No complications were observed.

CONCLUSIONS

The retear rates after DR-ARCR with absorbable sutures as medial-row anchors were 8.8% for complete retears of the tendon at the footprint and 1.7% for complete discontinuity of tendon around the medial-row anchors. This procedure provided a low retear rate around the medial-row anchors.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Arthroscopic knotless-anchor rotator cuff repair: a clinical and radiological evaluation

PURPOSE

The goal of this study was to evaluate the clinical and radiological results of the arthroscopic knotless-anchor Speed-Bridge technique, in particular the pattern and the rate of retears. The results were compared with a modified Suture-Bridge knot-tying technique (mDR). The hypothesis is that arthroscopic knotless-anchor Speed-Bridge rotator cuff repair is a sufficient technique to address supraspinatus tears and differs in pattern of retears when compared to mDR.

METHODS

This study includes twenty-two consecutive patients (8f/14m ø 63.3 ± 7.2 years) undergoing knotless-anchor Speed-Bridge repair. The subjective shoulder value (SSV), Constant score (CS) and Western Ontario Rotator Cuff (WORC) Score were used for clinical follow-up. MRI scans were conducted within 3 weeks post-operatively, after 1 and after 2 years for analysis of (a) tendon integrity (according to Sugaya), (b) muscle atrophy according to Thomazeau and (c) fatty infiltration. Results were compared with 20 patients operated in mDR (ø 61.2 ± 7.5 years).

RESULTS

The mean follow-up was 24.4 ± 4.7 months. The average SSV was 88.7 ± 14.9 %, the CS was 78.2 ± 13.2 points (contralateral side 78.5 ± 16.6) and the WORC Score averaged 87.1 ± 18.2 %. On magnetic resonance imaging, the integrity failure rate was 22.7 % (n = 5). The pattern of retear was a medial cuff failure in 2/5 cases (mDR 4/5, n.s.). Muscular atrophy or fatty degeneration did not increase between surgery and follow-up (n.s.). Compared with mDR (25 %) reconstruction, no significant differences were obtained regarding integrity failure rate and muscular atrophy (n.s.).

CONCLUSION

The modified knotless-anchor Speed-Bridge technique shows good to excellent clinical results as well as acceptable retear rates. This technique eliminates medial and lateral knot impingement. Concerning the potential reduction in the medial strangulation of the tendon, there is a need for further clinical research.

The optimum tension for bridging sutures in transosseous-equivalent rotator cuff repair: a cadaveric biomechanical study

BACKGROUND

Transosseous-equivalent (TOE) rotator cuff repair can increase contact area and contact pressure between the repaired cuff tendon and bony footprint and can show higher ultimate loads to failure and smaller gap formation compared with other repair techniques. However, it has been suggested that medial rotator cuff failure after TOE repair may result from increased bridging suture tension.

PURPOSE

To determine optimum bridging suture tension in TOE repair by evaluating footprint contact and construct failure characteristics at different tensions.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 18 fresh-frozen cadaveric shoulders, randomly divided into 3 groups, were constructed with a TOE configuration using the same medial suture anchor and placing a Tekscan sensing pad between the repaired rotator cuff tendon and footprint. Nine of the 18 shoulders were used to measure footprint contact characteristics. With use of the Tekscan measurement system, the contact pressure and area between the rotator cuff tendon and greater tuberosity were quantified for bridging suture tensions of 60, 90, and 120 N with glenohumeral abduction angles of 0° and 30° and humeral rotation angles of 30° (internal), 0°, and 30° (external). TOE constructs of all 18 shoulders then underwent construct failure testing (cyclic loading and load to failure) to determine the yield load, ultimate load, stiffness, hysteresis, strain, and failure mode at 60 and 120 N of tension.

RESULTS

As bridging suture tension increased, contact force, contact pressure, and peak pressure increased significantly at all positions (P < .05 for all). Regarding contact area, no significant differences were found between 90 and 120 N at all positions, although there were significant differences between 60 and 90 N. The construct failure test demonstrated no significant differences in any parameters according to various tensions (P > .05 for all).

CONCLUSION

Increasing bridging suture tension to over 90 N did not improve contact area but did increase contact force and pressure. Bridging suture tension did not significantly affect ultimate failure loads.

CLINICAL RELEVANCE

Considering the risks of overtensioning bridging sutures, it may be clinically more beneficial to keep bridging suture tension below 90 N.

Do patient age and sex influence tendon cell biology and clinical/radiographic outcomes after rotator cuff repair?

BACKGROUND

Many clinical and radiographic studies suggest that patient age and sex have an influence on rotator cuff (RC) repair outcomes. However, these findings result from retrospective statistical analyses and cannot provide a causal answer.

PURPOSE

To analyze whether age and sex influence the biological potential at the time of RC repair or midterm clinical and radiographic outcomes. Also assessed was the effect of the biological potential on intraindividual clinical/radiographic results.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 40 patients underwent arthroscopic RC repair. At the time of surgery (t = 0), supraspinatus tendon biopsy specimens were obtained, cultivated, and assessed for their biological potential, particularly (1) cell growth and (2) collagen type I production. After a follow-up at 24 months (t = 1), all patients were assessed by clinical scores (Constant score, subjective shoulder value, American Shoulder and Elbow Surgeons [ASES] score, and Western Ontario Rotator Cuff Index [WORC] score) and underwent magnetic resonance imaging to determine RC integrity. The data were examined for age- and sex-related differences and to identify the correlation between biological potential (t = 0) and clinical/radiographic outcome (t = 1).

RESULTS

The follow-up rate for the imaging and clinical evaluation was 100%. Age, but not sex, influenced the biological tendon cell parameters at t = 0. However, there was no effect of age or sex on the clinical and radiographic results at t = 1. Furthermore, no correlation was observed between the initial biological parameters and later clinical outcomes or radiographic RC integrity. Finally, there was no significant difference between intact and nonhealed repairs in terms of the respective clinical scores.

CONCLUSION

Age, but not sex, was found to have a negative effect on RC tendon cell biology. However, neither sex nor, in particular, a higher age influenced repair outcomes after 24 months.

Advances in biology and mechanics of rotator cuff repair

High initial fixation strength, mechanical stability and biological healing of the tendon-to-bone interface are the main goals after rotator cuff repair surgery. Advances in the understanding of rotator cuff biology and biomechanics as well as improvements in surgical techniques have led to the development of new strategies that may allow a tendon-to-bone interface healing process, rather than the formation of a fibrovascular scar tissue. Although single-row repair remains the most cost-effective technique to address a rotator cuff tear, some biological intervention has been recently introduced to improve tissue healing and clinical outcome of rotator cuff repair. Animal models are critical to ensure safety and efficacy of new treatment strategies; however, although rat shoulders as well as sheep and goats are considered the most appropriate models for studying rotator cuff pathology, no one of them can fully reproduce the human condition. Emerging therapies involve growth factors, stem cells and tissue engineering. Experimental application of growth factors and platelet-rich plasma demonstrated promising results, but has not yet been transferred into standardized clinical practice. Although preclinical animal studies showed promising results on the efficacy of enhanced biological approaches, application of these techniques in human rotator cuff repairs is still very limited. Randomized controlled clinical trials and post-marketing surveillance are needed to clearly prove the clinical efficacy and define proper indications for the use of combined biological approaches. The following review article outlines the state of the art of rotator cuff repair and the use of growth factors, scaffolds and stem cells therapy, providing future directions to improve tendon healing after rotator cuff repair.

LEVEL OF EVIDENCE

Expert opinion, Level V.

Suture placement near the musculotendinous junction in the supraspinatus: implications for rotator cuff repair

BACKGROUND

Transosseous-equivalent rotator cuff repair has an increased incidence of medial rotator cuff failure compared with single-row repair. No studies have evaluated the influence of the proximity of the suture row to the musculotendinous junction (MTJ) on cyclic gapping and failure properties.

HYPOTHESIS

A single row of horizontal mattress sutures placed within the supraspinatus tendon lateral to the MTJ will experience less gap formation and higher failure loads than a similar suture row placed at the MTJ.

STUDY DESIGN

Controlled laboratory study.

METHODS

Paired supraspinatus tendons were isolated from human cadaveric specimens and resected at the tendon insertion to the humerus. Randomized within a pair, a single row of 4 horizontal mattress sutures was placed either in the tendon 5 mm lateral to the MTJ or at the MTJ. The tied sutures secured the tendon to a fixture that ensured consistent placement of the suture row in the tendon and static fixation of the row. The muscle belly was gripped in a cryoclamp, and a servohydraulic materials testing machine was used to provide uniaxial tensile deformation for 500 cycles at 1 Hz, followed by load to failure at 1 mm/s. Fiducial markers with video tracking were used to quantify gap formation at the suture line, while the materials testing machine recorded loading for the cyclic and failure tests.

RESULTS

During cyclic loading, both constructs experienced gross initial gap formation, followed by progressive gap formation that plateaued after cycle 200. The MTJ specimens had significantly higher mean cumulative gapping than the tendon specimens: 3.6±1.0 mm versus 2.4±0.6 mm, respectively (P=.012). The tendon specimens had significantly higher mean loads to failure than did the MTJ specimens: 567.1±121.8 N versus 434.2±148.1 N, respectively (P=.013). The mean failure displacement did not differ between groups for the tendon and MTJ: 5.7±2.5 mm versus 4.5±2.0 mm, respectively (P=.144).

CONCLUSION

A horizontal suture row placed at the MTJ has inferior mechanical properties (increased gapping, decreased load support) as compared with a suture row placed 5 mm laterally within the tendon.

CLINICAL RELEVANCE

The integrity of rotator cuff repair may be compromised if sutures are placed too close to the MTJ.

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.

Management of disorders of the rotator cuff: proceedings of the ISAKOS upper extremity committee consensus meeting

The goal of this article is to consolidate the International Society of Arthroscopy, Knee Surgery & Orthopaedic Sports Medicine (ISAKOS) Upper Extremity Committee's (UEC's) current knowledge on rotator cuff disease and management, as well as highlight key unresolved issues. The rotator cuff is an anatomically complex structure important for providing glenohumeral function and stability as part of a closed chain system. Current consensus suggests rotator cuff injuries are most accurately diagnosed, at levels similar to diagnosis by magnetic resonance imaging, with a combination of cuff- and impingement-specific clinical tests. Updates in the understanding of acromion morphology, the insertional anatomy of the rotator cuff, and the role of suprascapular nerve release may require changes to current classification systems and surgical strategies. Although initial management focuses on nonoperative protocols, discussion continues on whether surgery for isolated impingement is clinically more beneficial than rehabilitation. However, clear indications have yet to be established for the use of single- versus double-row repair because evidence confirms neither is clinically efficacious than the other. Biceps tenodesis, however, in non-isolated cuff tears has proven more successful in addressing the etiology of shoulder pain and yields improved outcomes over tenotomy. Data reviewing the benefits of tendon transfers, shoulder prostheses, and mechanical scaffolds, as well as new research on the potential benefit of platelet-rich plasma, pluripotential stem cells, and gene therapies, will also be presented.

Cyclic loading biomechanical analysis of the pullout strengths of rotator cuff and glenoid anchors: 2013 update

PURPOSE

The purpose of this study was to evaluate the biomechanical and design characteristics of newer suture anchors under cyclic loading.

METHODS

Suture anchors were tested in fresh porcine cortical and cancellous bone by cyclic loading (10 to 100 N for 200 cycles) followed by destructive testing parallel to the insertion axis at 12.5 mm per second. End points included ultimate failure load, displacement at 100 and 200 cycles, failure mode, and stiffness. Anchors tested included ReelX (Stryker Endoscopy, San Jose, CA); Footprint Ultra PK (4.5 and 5.5 mm) (Smith & Nephew, Andover, MA); TwinFix (4.5, 5.5, and 6.5 mm made from polyether ether ketone [PEEK], hydroxyapatite [HA], and titanium [Ti]) (Smith & Nephew Endoscopy, Andover, MA); Morphix (2.5 and 5.5 mm) (MedShape Solutions, Atlanta, GA); CrossFT BC (ConMed-Linvatec, Largo, FL); JuggerKnot (1.5 and 2.8 mm) (Biomet Sports Medicine, Warsaw, IN); Healicoil (Smith & Nephew Endoscopy, Andover, MA); Quattro (X, Link, and GL) (Cayenne Medical, Scottsdale, AZ); Healix (Biocryl Rapide [BR], PEEK, and Ti) (DePuy Mitek, Raynham, MA); Twin Loop (3.5 mm, PEEK) (Stryker Endoscopy, San Jose, CA); PressFT (2.1 and 2.6 mm) (ConMed Linvatec, Largo FL); Y-Knot (ConMed Linvatec, Largo FL); Gryphon (BR and PEEK) (DePuy Mitek, Raynham, MA); and Iconix (1, 2, and 3) (Stryker Endoscopy, San Jose, CA).

RESULTS

Rotator cuff anchors showed greater failure loads than did glenoid anchors in metaphyseal bone (rotator cuff anchors 448 N v glenoid anchors 296 N) (P = .001) and cancellous bone (rotator cuff anchors 435 N v glenoid anchors 225 N) (P < .001). No anchors reached 5 mm of displacement during cyclic loading. TwinFix anchors showed greater displacement at 100 (P = .014) and 200 cycles (P = .036) than did other rotator cuff anchors, although the ReelX and Morphix showed the greatest displacements. Rotator cuff anchors failed principally by eyelet breaking, whereas glenoid anchors failed more often by anchor pullout than by any other mode. No differences in stiffness were observed across the different rotator cuff and glenoid anchors tested.

CONCLUSIONS

Rotator cuff anchors showed higher failure strengths than did glenoid anchors, regardless of bone type. TwinFix anchors showed more cyclic displacement than did other rotator cuff anchors (except the ReelX and Morphix anchors) and the glenoid anchors tested. The failure mode was dependent on the specific anchor.

CLINICAL RELEVANCE

Suture anchor constructs tested showed that failure load is dependent on anchor type (rotator cuff anchor or glenoid anchor) but not on anchor location (cancellous or cortical bone).

Arthroscopic single-row modified mason-allen repair versus double-row suture bridge reconstruction for supraspinatus tendon tears: a matched-pair analysis

BACKGROUND

Arthroscopic double-row fixation of supraspinatus tendon tears compared with single-row techniques is still a matter of debate.

HYPOTHESIS

Arthroscopic double-row rotator cuff repair using the suture bridge technique provides better clinical results and lower retear rates than does single-row repair using a modified Mason-Allen stitch technique.

STUDY DESIGN

Cohort study; Level of evidence 3.

METHODS

Forty patients underwent either an arthroscopic single-row modified Mason-Allen stitch (SR) (n = 20; mean age ± SD, 61.5 ± 7.4 y) or a modified suture bridge double-row repair (DR) (n = 20; age, 61.2 ± 7.5 y). The anteroposterior extension was classified as Bateman I in 10% and Bateman II in 90% of patients in the SR group and as Bateman II in 80% and Bateman III in 20% of patients in the DR group. Patients were matched for sex and age. The subjective shoulder value (SSV), Constant-Murley score (CS), and Western Ontario Rotator Cuff Index (WORC) were used for clinical follow-up. Furthermore, MRI scans were conducted for analysis of tendon integrity, muscle atrophy, and fatty infiltration via semiquantitative signal intensity analysis. In addition, re-defect patterns were evaluated.

RESULTS

The mean follow-up time in the SR group was 16.8 ± 4.6 months. The mean SSV was 91.0% ± 8.8%, mean CS was 82.2 ± 8.1 (contralateral side, 88.8 ± 5.3), and mean WORC score was 96.5% ± 3.2%. The mean follow-up time in the DR group was 23.4 ± 2.9 months, with patients achieving scores of 92.9% ± 9.6% for the SSV, 77.0 ± 8.6 for the CS (contralateral side, 76.7 ± 17.1), and 90.7% ± 12.6% for the WORC (P > .05). No significant differences were detected in the clinical outcome between groups. Tendon integrity was as follows. Type 1, none in either group; type 2, 4 SR and 5 DR; type 3, 9 SR and 10 DR; type 4, 3 SR and 3 DR; and type 5, 3 SR and 2 DR. The failure rate was 31.6% (n = 6) in the SR group and 25% (n = 5) in the DR group (P > .05). No significant differences were obtained for muscular atrophy or fatty degeneration (SR group, 0.94 ± 0.16; DR group, 1.15 ± 0.5) (P > .05). Re-defects revealed lateral cuff failure in 83.3% of SR patients in contrast to patients treated with DR techniques. The re-defect pattern was medial cuff failure in 80% of the patients.

CONCLUSION

The clinical results after modified Mason-Allen single-row versus double-mattress suture bridge technique did not demonstrate significant differences in a matched patient cohort. Concerning the failure mode, single- and double-row techniques seem to demonstrate different re-defect patterns.

Characteristic retear patterns assessed by magnetic resonance imaging after arthroscopic double-row rotator cuff repair

PURPOSE

The purpose of this study was to examine magnetic resonance imaging (MRI) findings and elucidate retear pattern and its characteristics after surgical repair of the rotator cuff using an arthroscopic double-row suture anchor (DRSA) method.

METHODS

Forty-seven patients with complete rotator cuff tears treated by the DRSA method under arthroscopy whose repair condition was assessed by MRI approximately 12 months after the procedure were included in the study. The mean age at treatment was 65 years (range, 42 to 82 years). The mean follow-up period was 26 months (range, 24 to 32 months).

RESULT

The repair integrity was classified into 5 groups according to MRI findings. A well-repaired tendon was seen in 34 shoulders. Partial retearing of the deep layer was observed in 2. Partial retearing of the superficial layer around the medial anchors was observed in 3. Complete retearing of the tendon around the medial anchors with a well-preserved footprint was observed in 4. Complete retearing of the tendon from the footprint was observed in 4. The retear patterns involving superficial retearing and complete retearing around the medial anchors were unexpected and unique. These types of retears seem to be characteristic of the DRSA method and were seen in cases with medium-sized tears. The incidence of characteristic retearing was 7 of 47.

CONCLUSIONS

Superficial-side partial tearing and complete tearing around the medial-row anchors with a well-repaired tendon on the footprint could be characteristics of the DRSA method. These retear patterns were observed in 7 of 13 retear cases and 7 of 47 cases overall. The retear rate by the characteristic retear was high. Exploring the causes of this retear and preventing it could lead to better clinical results with the DRSA method.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Biomechanical comparison of four double-row speed-bridging rotator cuff repair techniques with or without medial or lateral row enhancement

BACKGROUND

Biomechanical comparison of four different Speed-Bridge configurations with or without medial or lateral row reinforcement. Reinforcement of the knotless Speed-Bridge double-row repair technique with additional medial mattress- or lateral single-stitches was hypothesized to improve biomechanical repair stability at time zero.

METHODS

Controlled laboratory study: In 36 porcine fresh-frozen shoulders, the infraspinatus tendons were dissected and shoulders were randomized to four groups: (1) Speed-Bridge technique with single tendon perforation per anchor (STP); (2) Speed-Bridge technique with double tendon perforation per anchor (DTP); (3) Speed-Bridge technique with medial mattress-stitch reinforcement (MMS); (4) Speed-Bridge technique with lateral single-stitch reinforcement (LSS). All repairs were cyclically loaded from 10-60 N up to 10-200 N (20 N stepwise increase) using a material testing device. Forces at 3 and 5 mm gap formation, mode of failure and maximum load to failure were recorded.

RESULTS

The MMS-technique with double tendon perforation showed significantly higher ultimate tensile strength (338.9 ± 90.0 N) than DTP (228.3 ± 99.9 N), LSS (188.9 ± 62.5 N) and STP-technique (122.2 ± 33.8 N). Furthermore, the MMS-technique provided increased maximal force resistance until 3 and 5 mm gap formation (3 mm: 77.8 ± 18.6 N; 5 mm: 113.3 ± 36.1 N) compared with LSS, DTP and STP (P < 0.05 for each 3 and 5 mm gap formation). Failure mode was medial row defect by tendon sawing first, then laterally. No anchor pullout occurred.

CONCLUSION

Double tendon perforation per anchor and additional medial mattress stitches significantly enhance biomechanical construct stability at time zero in this ex vivo model when compared with the all-knotless Speed-Bridge rotator cuff repair.