Biomechanical comparison of knotless anchor repair versus simple suture repair for type II SLAP lesions

Portal Closure After Segmental Posterior Labral Repair for Posterior Shoulder Instability

Posterior instability, although an uncommon shoulder pathology, is reported most frequently in the athletic population. Arthroscopic repair has emerged as the main surgical treatment modality for posterior instability. However, when compared with arthroscopic repair for anterior instability, the results of this procedure remain suboptimal. The creation of iatrogenic defects in the capsule, due to cannula placement, is a possible culprit. Because these defects typically do not heal satisfactorily, they become stress risers within the capsule itself, which may lead to recurrent instability or an otherwise compromised repair construct. Therefore, we find that routine intraoperative repair of these defects after repair can reduce the risk of injury and possibly improve long-term outcomes. In this article, we illustrate the repair of a posterior segmental tear using all-suture knotless implants with closure of the posterior and posterior-inferior portals after stabilization.

Biceps Tenodesis Versus Superior Labral Anterior and Posterior (SLAP) Lesion Repair for the Treatment of SLAP Lesion in Overhead Athletes: A Systematic Review and Meta-analysis

BACKGROUND

Superior labral anterior and posterior (SLAP) lesions are common injuries in overhead athletes. As a surgical treatment for SLAP lesions, SLAP repair has been traditionally performed. Recently, biceps tenodesis has been performed as an alternative treatment option; however, there is no review for outcome comparisons between these 2 procedures in overhead athletes.

PURPOSE

The aim of this study was to compare the outcomes of SLAP repair versus biceps tenodesis, especially in overhead athletes with SLAP lesions.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

An electronic literature search was performed in Medline, Embase, Scopus, and the Cochrane Library. The studies were appraised using the Methodological Index for Non-randomized Studies (MINORS) tool. Studies that had a minimum follow-up of 2 years, included only patients with SLAP lesions without other major shoulder pathologies, and included only patients who engaged in overhead sports were included. The functional outcomes of the American Shoulder and Elbow Surgeons (ASES) score, rate of return to sport, rate of return to preinjury level of sport, and complication rate were subjected to meta-analysis.

RESULTS

A total of 332 articles were identified, and 13 were included in the systematic review. Even though the postoperative ASES scores were slightly higher in the biceps tenodesis group than in the SLAP repair group, no statistically significant differences were found between the groups (biceps tenodesis, 95% CI = 91.71-96.75, I² = 0.00; SLAP repair, 95% CI = 85.47-94.46, I² = 16.3; P = .085) The rate of return to sport and the return to preinjury level of sport were slightly higher in the biceps tenodesis group than in the SLAP repair group; however, in meta-analysis these factors did not reach statistical significance (return to sport: biceps tenodesis, 95% CI = 0.66-0.91, I² = 0.00; SLAP repair, 95% CI = 0.68-0.93, I² = 70.23; P = .94) (return to preinjury level of sport: biceps tenodesis, 95% CI = 0.61-0.89, I² = 17.78; SLAP repair, 95% CI = 0.53-0.82, I² = 58.07; P = .37). The biceps tenodesis group showed a lower complication rate compared with the SLAP repair group without statistical significance (biceps tenodesis, 95% CI = 0.013-0.145, I² = 0.00; SLAP repair, 95% CI = 0.049-0.143, I² = 0.00; P = .25).

CONCLUSION

The results of biceps tenodesis, compared with SLAP repair, were not inferior in the surgical treatment of overhead athletes with SLAP lesions with regard to the ASES score, rate of return to sport, rate of return to preinjury level of sport, and complication rate. Further high-level, randomized controlled studies are needed to confirm this result.

Disabled Throwing Shoulder: 2021 Update: Part 2-Pathomechanics and Treatment

The purpose of this paper is to provide updated information for sports healthcare specialists regarding the disabled throwing shoulder (DTS). A panel of experts, recognized for their experience and expertise in this field, was assembled to address and provide updated information on several topics that have been identified as key areas in creating the DTS spectrum. Each panel member submitted a concise presentation on one of the topics within these areas, each of which were then edited and sent back to the group for their comments and consensus agreement in each area. Part two presents the following consensus conclusions and summary findings regarding pathomechanics and treatment, including (1) internal impingement results from a combination of scapular protraction and humeral head translation; (2) the clinically significant labral injury that represents pathoanatomy can occur at any position around the glenoid, with posterior injuries most common; (3) meticulous history and physical examination, with a thorough kinetic chain assessment, is necessary to comprehensively identify all the factors in the DTS and clinically significant labral injury; (4) surgical treatment should be carefully performed, with specific indications and techniques incorporating low profile implants posterior to the biceps that avoid capsular constraint; (5) rehabilitation should correct all kinetic chain deficits while also developing high-functioning, throwing-specific motor patterns and proper distribution of loads and forces across all joints during throwing; and (6) injury risk modification must focus on individualized athlete workload to avoid overuse. LEVEL OF EVIDENCE: V, expert opinion.

Biomechanical Studies for Glenoid Based Labral Repairs With Suture Anchors Do Not Use Consistent Testing Methods: A Critical Systematic Review

PURPOSE

The purpose of this systematic review was to investigate variability in biomechanical testing protocols for laboratory-based studies using suture anchors for glenohumeral shoulder instability and SLAP lesion repair.

METHODS

A systematic review of Medline, Embase, Scopus, and Google Scholar using Covidence software was performed for all biomechanical studies investigating labral-based suture anchor repair for shoulder instability and SLAP lesions. Clinical studies, technical notes or surgical technique descriptions, or studies treating glenoid bone loss or capsulorrhaphy were excluded. Risk of bias (ROB) was assessed with the ROBINS-I tool. Study quality was assessed with the Quality Appraisal for Cadaveric Studies. Heterogeneity was assessed with the I² statistic.

RESULTS

A total of 41 studies were included. ROB was serious and critical in 27 studies, moderate in 13, and low in 1; 6 studies had high quality, 21 good quality, 10 moderate quality, 2 low quality, and 2 very low quality. Thirty-one studies used and 22 studies included cyclic loading. Angle of anchor insertion was reported by 33 studies. The force vector for displacement varied. The most common directions were perpendicular to the glenoid (n = 9), and anteroinferior or anterior (n = 8). The most common outcome measures were load to failure (n = 35), failure mode (n = 23), and stiffness (n = 21). Other outcome measures included load at displacement, displacement at failure, tensile load at displacement, translation, energy absorbed, cycles to failure, contact pressure, and elongation.

CONCLUSION

This systematic review demonstrated a clear lack of consistency in those cadaver studies that investigated biomechanical properties after surgical repair with suture anchors for shoulder instability and SLAP lesions. Testing methods between studies varied substantially with no universally applied standard for preloading, load to failure and cyclic loading protocols, insertion angles of suture anchors, or direction of loading. To allow comparability between studies standardization of testing protocols is strongly recommended.

Knotless All-Inside Arthroscopic Modified Broström Procedure for Lateral Ankle Instability

One reported complication of the arthroscopic modified Broström operation is pain caused by the suture anchoring knot. We hypothesized that a knotless technique could reduce such pain. Therefore, in this study we evaluated the clinical and radiological outcomes after knotless all-inside arthroscopic modified Broström operation for lateral ankle instability. From July 2017 to November 2017, 28 patients were treated. Clinical and radiological features were evaluated preoperatively and 3, 6, and 12 months postoperatively using the American Orthopaedic Foot & Ankle Society ankle-hindfoot scale score, visual analogue scale score for pain, anterior talar drawer test, and talar tilt angle. The mean age of the 28 patients (14 men, 14 women) was 41.71 ± 17.19 years. Three (10.7%) complications, but no knot-associated pain, occurred. The clinical and radiological outcomes were significantly improved 12 months postoperatively compared with preoperative outcomes (all p < .05). Knotless all-inside arthroscopic modified Broström operation for lateral ankle instability avoided knot-associated pain and improved not only patient satisfaction but also clinical and radiological outcomes.

Knotted Versus Knotless Anchors for Labral Repair in the Shoulder: A Systematic Review

PURPOSE

To compare biomechanical and clinical outcomes between knotless and knotted anchors in arthroscopic labral repair, specifically in (1) Bankart repair, (2) SLAP repair, (3) posterior labral repair, and (4) remplissage augmentation of Bankart repair.

METHODS

MEDLINE, EMBASE, and the Cochrane Library were searched according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to find biomechanical and clinical studies comparing knotted and knotless anchors using the search term "knotless anchor."

RESULTS

Overall, 17 studies met inclusion criteria. There were 7 studies evaluating the biomechanical outcomes, of which 5 found mixed results between knotted and knotless anchors for arthroscopic Bankart repair, 1 demonstrated a difference for SLAP repair favoring knotless anchors, and 2 showed no significant difference for Remplissage in terms of ultimate load-to-failure. Four studies evaluated knotless labral anchors compared with knotted anchors in patients undergoing arthroscopic Bankart repair with no significant differences in outcomes reported between the 2 anchor types, except in one study that found an improved visual analog scale score and a lower recurrence and revision rate with knotted anchors. Five studies evaluated knotless anchors compared with knotted anchors in patients undergoing SLAP repair, and none of the included studies found any significant differences in the patient reported outcome measures or revision rates. Of the 5 studies comparing operative time, 4 found a reduced time with knotless anchors.

CONCLUSIONS

The clinical results show no significant differences in outcomes between knotless and knotted anchors for labral repair in the shoulder, including Bankart repair, SLAP repair, and posterior labral repair. However, there was conflicting evidence supporting knotless or knotted anchors in the biomechanical studies. However, operative times may be reduced with the use of knotless anchors.

LEVEL OF EVIDENCE

III, A Systematic Review of Level II and III studies.

Reported Technical Aspects of Type II SLAP Lesion Repairs in Athletes

Purpose

To systematically review the available literature to further describe and report the available data on SLAP repair techniques and the association with outcomes.

Methods

A systematic review of literature was performed on manuscripts describing type II SLAP repairs in athletes. Selection criteria included studies reporting exclusively type II SLAP tears without concomitant pathology, minimum 2-year postoperative follow-up, use of anchor fixation, and return to previous level of play data available. We extracted patient outcome as well as surgical construct details from each article. Average outcomes and return to play rates were calculated and substratified further by athlete type. Return to play rates were compared by repair constructs with the Student t test.

Results

Initial search resulted in 107 articles. After exclusion criteria were applied, 17 articles were included in the final analysis. Overall, 84% of patients had good-to-excellent results. Of all athletes, 66% returned to previous level of play. There was significant variation in reported technique in terms of anchor number, location, material, suture type, and knotless versus knotted constructs. No significant difference was reported in outcomes in comparison of suture type (P-value .96) or knotted versus knotless constructs (P-value .91). Given the significant variability in reporting, no statistical analysis was felt able to be performed on anchor location and number.

Conclusions

Repair of type II SLAP tears in athletes is a difficult problem to treat with overall low return to play despite a high rate of “good” outcomes when assessed by outcome measures. Significant variability exists in surgical technique, as well as reporting of surgical technique, potentially limiting the ability to define the best or most effective technique for SLAP repair.

Level of Evidence

IV, systematic review of level III and level IV studies.

Biceps Tenodesis for Superior Labrum Anterior-Posterior Tear in the Overhead Athlete: A Systematic Review

BACKGROUND

Superior labrum anterior-posterior (SLAP) lesion is a common shoulder injury, particularly in overhead athletes. While surgical management has traditionally consisted of SLAP repair, high rates of revision and complications have led to alternative techniques, such as biceps tenodesis (BT). While BT is commonly reserved for older nonoverhead athletes, indications for its use have expanded in recent years.

PURPOSE

To determine functional outcomes and return-to-sport rates among overhead athletes after BT for SLAP tear.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was performed for any articles published before July 2019. The search phrase "labral tear" was used to capture maximum results, followed by keyword inclusion of "SLAP tear" and "biceps tenodesis." Inclusion criteria included outcome studies of BT for isolated SLAP tear in athletes participating in any overhead sports, not limited to throwing alone. Abstracts and manuscripts were independently reviewed to determine eligibility. When clearly delineated, outcome variables from multiple studies were combined.

RESULTS

After full review, 8 articles met inclusion criteria (99 athletes; mean age, 19.8-47 years), with baseball and softball players the most common among them (n = 62). Type II SLAP tear was the most common diagnosis, and 0% to 44% of athletes had a failed previous SLAP repair before undergoing BT. Only 1 study included patients with concomitant rotator cuff repair. Open subpectoral BT was most commonly used, and complication rates ranged from 0% to 14%, with wound erythema, traumatic biceps tendon rupture, brachial plexus neurapraxia, and adhesive capsulitis being reported. Combined reported postoperative functional scores were as follows: American Shoulder and Elbow Surgeons, 81.7 to 97; 12-Item Short Form Health Survey physical, 50 to 54; visual analog scale for pain, 0.8-1.5; Kerlan Jobe Orthopaedic Clinic, 66 to 79; and satisfaction, 80% to 87%. The overall return-to-sports rate for overhead athletes was 70% (60 of 86). For studies that clearly delineated outcomes based on level of play/athlete, the combined return-to-sports rate was 69% (11 of 16) for recreational overhead athletes, 80% (4 of 5) for competitive/collegiate athletes, and 60% (18 of 30) for professionals.

CONCLUSION

BT in the overhead athlete offers encouraging functional outcomes and return-to-sports rates, particularly in the recreational athlete. It can be successfully performed as an index operation rather than SLAP repair, as well as in a younger patient population. Careful consideration should be given to elite overhead athletes, particularly pitchers, who tend to experience poorer outcomes.

A Novel Technique of Arthroscopic Ankle Lateral Ligament Repair Using a Knotless Suture Anchor

Background:

Although arthroscopic lateral ligament repair (ALLR) with suture anchors for chronic lateral ankle instability has become widely accepted, some complications have been reported as well. Establishment of a new technique is essential for better clinical outcomes after ALLR.

Purpose

To report a novel technique and good clinical results of ALLR using a knotless suture anchor.

Study Design:

Case series; Level of evidence, 4.

Methods:

We examined 30 patients (16 men and 14 women) who underwent ALLR. The mean age of the patients was 30.0 years, and the average period of postoperative monitoring was 21 months. The Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale was used for clinical evaluation postoperatively, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) for patient-reported results. Surgical complications were also examined.

Results:

The JSSF ankle-hindfoot scale showed a significant improvement from preoperatively to follow-up (from 72.1 to 96.1; P < 0.001), and the SAFE-Q was significantly improved in all subscales (pain and pain-related, physical function and daily living, social function, shoe-related, and general health and well-being; P < 0.004 for all). Complications included residual joint pain due to remaining osteophytes in 1 case, scar pain of the accessory anterolateral portal in 2 cases, and positive Tinel sign indicative of superficial peroneal nerve irritation at the anterolateral portal in 1 case.

Conclusion:

The clinical results of the novel ALLR technique were overall satisfactory. Knot-related complications, one of the main reasons for postoperative complications, were reduced by using a knotless suture anchor.

Arthroscopic Low-Profile Knotless Repair of SLAP Tears With Suture Tape

SLAP tears have been a controversial topic in shoulder surgery for decades. The indications for repair of SLAP tears, as well as the methods of repair, have undergone a recent evolution. The use of intra-articular knots for SLAP repair has fallen out of favor because of potential abrasive damage to the rotator cuff and glenohumeral articular cartilage due to knot migration and prominence. In response to this potential iatrogenic injury, arthroscopic techniques have undergone an evolution using advanced techniques with low-profile knotless repairs. We describe our preferred low-profile knotless technique for SLAP repair using LabralTape (Arthrex) in a horizontal mattress configuration.

Biomechanical Comparison of Knotless All-Suture Anchors and Knotted All-Suture Anchors in Type II SLAP Lesions: A Cadaveric Study

PURPOSE

To compare the biomechanical performance of knotless versus knotted all-suture anchors for the repair of type II SLAP lesions with a simulated peel-back mechanism.

METHODS

Twenty paired cadaveric shoulders were used. A standardized type II SLAP repair was performed using knotless (group A) or knotted (group B) all-suture anchors. The long head of the biceps (LHB) tendon was loaded in a posterior direction to simulate the peel-back mechanism. Cyclic loading was performed followed by load-to-failure testing. Stiffness, load at 1 and 2 mm of displacement, load to repair failure, load to ultimate failure, and failure modes were assessed.

RESULTS

The mean load to repair failure was similar in groups A (179.99 ± 58.42 N) and B (167.83 ± 44.27 N, P = .530). The mean load to ultimate failure was 230 ± 95.93 N in group A and 229.48 ± 78.45 N in group B and did not differ significantly (P = .958). Stiffness (P = .980), as well as load at 1 mm (P = .721) and 2 mm (P = .849) of displacement, did not differ significantly between groups. In 16 of the 20 specimens (7 in group A and 9 in group B), ultimate failure occurred at the proximal LHB tendon. Failed occurred through slippage of the labrum in 1 specimen in each group and through anchor pullout in 2 specimens in group A.

CONCLUSIONS

Knotless and knotted all-suture anchors displayed high initial fixation strength with no significant differences between groups in type II SLAP lesions. Ultimate failure occurred predominantly as tears of the proximal LHB tendon.

CLINICAL RELEVANCE

All-suture anchors have a smaller diameter than solid anchors, can be inserted through curved guides, preserve bone stock, and facilitate postoperative imaging. There is a paucity of literature investigating the biomechanical capacities of knotless versus knotted all-suture anchors in type II SLAP repair.

Biomechanical comparison of knotless vs. knotted suture anchors in the acetabular rim with respect to bone density

BACKGROUND

Acetabular labral tears are managed with suture anchors providing good clinical outcomes. Knotless anchors are easier to use and have a quicker insertion time compared to knotted anchors. The purpose of this study was to compare the biomechanical behavior of two different anchor designs (knotted vs. knotless) in ultimate load testing in correlation with bone density in the acetabular rim.

METHODS

Eighteen knotted Bio-FASTak and seventeen knotless PushLock anchors (both: Arthrex Inc., Naples, FL, USA) were inserted in the rims of two human acetabula, with known bone density distribution. The anchors were subjected to load-to-failure tests. Anchors were additionally tested in solid polyurethane foam with defined densities.

FINDINGS

The Bio-FASTak group showed higher survival rates at 1, 2, and 3 mm displacement and was able to withstand significantly higher loads at 3 mm displacement (p = 0.031). There was no statistically significant difference in stiffness (p = 0.087), yield- (p = 0.190), and ultimate load (p = 0.222) between the two groups. Only the PushLock group showed correlation between bone volume over total volume (BV/TV) and stiffness (R = 0.750, p = 0.086) and between BV/TV and yield load (R = 0.838, p = 0.037). Experiments on solid polyurethane foam confirmed the correlation between the mechanical properties and tissue density for the same anchor.

INTERPRETATION

PushLock shows similar biomechanical properties to the Bio-FASTak, but eliminates knot tying and potentially abrasive knots. In addition, biomechanical properties of the PushLock are governed by local bone density.

Surgical management of type II superior labrum anterior posterior (SLAP) lesions: a review of outcomes and prognostic indicators

A Type II SLAP (superior labrum anterior posterior) lesion is a tear of the superior glenoid labrum with involvement of the long head of the biceps tendon insertion. In patients that do not improve with conservative treatment, there is a great deal of variability in the surgical management of these injuries that includes arthroscopic SLAP repair, arthroscopic SLAP repair with biceps tenodesis, biceps tenodesis alone and biceps tenotomy. Each surgical technique has specific effects on a patient's postoperative course and functional recovery. Rehabilitation strategies may be best formulated on an individual basis with an open line of communication between the operating surgeon and the physical therapist. Despite an increased incidence in treatment, there is currently no consensus on the optimal surgical procedure or treatment algorithm for Type II SLAP injuries. However, in middle-aged or older patients (>35) with Type II SLAP tears, either arthroscopic suprapectoral or mini-open subpectoral biceps tenodesis is recommended due to the higher failure rates observed with arthroscopic SLAP repair in this patient group. Although more patients present with a 'Popeye' sign after biceps tenotomy, long-term functional outcome is similar between biceps tenodesis compared to tenotomy. However, more patients will experience biceps fatigue or cramping after the tenotomy procedure. Biceps tenodesis is preferred in younger, more active patients, while tenotomy is preferred in the middle-aged or older and lower demand patients. The aim of this paper is to provide a brief description of the different surgical techniques employed to address Type II SLAP lesions (arthroscopic repair, biceps tenodesis, and biceps tenotomy) and provide a review of available literature regarding outcomes and prognostic factors associated with each technique.

Assessments of activities of daily living after arthroscopic SLAP repair with knot-tying versus knotless suture anchors

PURPOSE

The clinical influence of knot-tying or knotless anchor systems for the arthroscopic repair of SLAP lesions (superior labrum lesion from anterior to posterior) remain unclear.

MATERIALS AND METHODS

In a retrospective cohort analysis, 61 of 78 (78.2%) patients with isolated symptomatic SLAP II lesions were examined with a minimum of 24 months after arthroscopic SLAP repair compared to a control group: 28 patients with knot-tying anchors (group I, G1; 28.95 ± 9.48 years, 23 male/5 female), 33 with knotless anchors (group II, G2; 31 ± 10.09 years, 26 male/7 female) and 140 healthy volunteers (group III, G3; 30.9 ± 8.9 years, 109 male/31 female). The clinical assessment included an examination and estimated parameters of ADL (activities of daily living), the CS (Constant score), ASES (American Shoulder and Elbow score), DASH (disability of arm-shoulder hand) and the RS (Rowe score).

RESULTS

The ROM analysis recorded no significant differences for the external rotation in 0° abduction (G1 63.75° ± 15.55° versus = vs G2 65.30° ± 18.15°; p_{ERG1 vs G2} = 0.72). The clinical outcomes revealed significantly decreased pain status in G1 for the O'brien test and in G2 for the Palm-up test, whereas Yergason test showed similar pain levels (p_O'brien = 0.03; p_{palm up} = 0.02; p_yergason > 0.5). The pulley associated rotator cuff tests revealed a significantly inferior force status in G2 compared to G1 (p_lift-off = 0.005, p_Jobe = 0.02) whereas the further rotator cuff assessments were equal. In general, the intervention group showed increased pain level and functional deficits compared to the G3. The score analysis detected no significant differences with P_{CSG1 vs G2}, P_{ASESG1 vs G2}, P_{DASHG1 vs G2} and P_{RSG1 vs G2} all > 0.05 and significant impairments compared to G3 in all scores p_{G1/G2 vs G3} < 0.05 (CS_G1 = 88.28 ± 14.42, CS_G2=92.73 ± 9.24, CS_G3 = 96.2 ± 4.96; ASES_G1 = 81.10 ± 21.69, ASES_G2 = 85.35 ± 17.12, ASES_G3 = 94.95 ± 10.39,; DASH_G1= 35.75 ± 13.44, DASH_G2 = 36.03 ± 17.55, DASH_G3 = 27.13 ± 6.52; RS_G1 = 90.71 ± 9.88, RS_G2 = 88.33 ± 11.22, RS_G3= 92.96 ± 11.27).

CONCLUSIONS

The clinical assessment revealed for both anchor systems similar outcomes but showed general underestimated impairments after the SLAP repair surgery compared to the healthy control. The clinical status only marginally differed between both techniques, wherefore the present assessment of ADL allowed no recommendation of one of these two specific surgery technique for SLAP repair.

SLAP lesions: current controversies

Knowledge of the pertinent anatomy, pathogenesis, clinical presentation and treatment of the spectrum of injuries involving the superior glenoid labrum and biceps origin is required in treating the patient with a superior labrum anterior and posterior (SLAP) tear.Despite the plethora of literature regarding SLAP lesions, their clinical diagnosis remains challenging for a number of reasons.First, the diagnostic value of many of the available physical examination tests is inconsistent and ambiguous.Second, SLAP lesions most commonly occur concomitantly with other shoulder injuries.Third, SLAP lesions have no specific associated pain pattern.Outcomes following surgical treatment of SLAP tears vary depending on the method of treatment, associated pathology and patient characteristics.Biceps tenodesis has been receiving increasing attention as a possible treatment for SLAP tears. Cite this article: EFORT Open Rev 2019;4:25-32. DOI: 10.1302/2058-5241.4.180033.

Effect of Anterior Anchor on Clinical Outcomes of Type II SLAP Repairs in an Active Population

This study evaluated the role of anchor position in persistence of pain and/or revision biceps tenodesis after arthroscopic repair of type II superior labrum anterior and posterior (SLAP) lesions and assessed for patient- and injury-specific variables influencing clinical outcomes. Active-duty service members who underwent arthroscopic repair of type II SLAP lesions between March 1, 2007, and January 23, 2012, were identified. Patients with less than 2-year clinical follow-up; type I, III, and IV SLAP lesions; and primary treatment with biceps tenodesis and/or rotator cuff repair at the time of index surgery were excluded. Demographic, preoperative, and operative variables, including anchor positions, were reviewed and evaluated for association with outcomes. Total failure rate (defined as either surgical and/or clinical failure), anchor position, and return to military function were the primary outcomes of interest. Forty-nine patients underwent type II SLAP repairs with a mean follow-up of 52.3 months. Forty-eight (97.9%) were men, and mean age was 35.2 years. Eleven patients (22%) underwent subsequent subpectoral biceps tenodesis. Forty patients (82%) returned to military function, whereas 9 patients (18%) had medical discharge for significant, rate-limiting, shoulder pain. Age was a significant predictor of surgical failure. Patients with anchor position anterior to the biceps attachment had no increased risk of clinical or surgical failure compared with patients with only posterior-based anchors. Anchor placement anterior to the biceps tendon was not associated with inferior outcomes. Younger age was shown to be a poor prognostic factor in patients' ability to return to active duty. Revision with biceps tenodesis showed significant utility in achieving good clinical outcomes and return to duty in more than 90% of patients. Patient-, injury-, and surgery-specific variables need to be identified as prognostic indicators so that clinical outcomes can continue to be improved. [Orthopedics. 2019; 42(1):e32-e38.].

Remplissage Using Interconnected Knotless Anchors: Superior Biomechanical Properties to a Knotted Technique?

PURPOSE

To evaluate the biomechanical fixation strength and gap formation of 2 different remplissage fixation methods (double pulley knotted construct and interconnected knotless repair construct) in cadaver specimens.

METHODS

Seven matched pairs of human cadaveric shoulders were used for testing (mean age, 56 ± 10 years). A shoulder from each matched pair was randomly selected to receive a Hill-Sachs remplissage using either a knotted (No. 2 FiberWire double pulley with 3.0-mm SutureTak anchors) or knotless (coreless No. 2 FiberWire interconnected between 3.9-mm knotless CorkScrew anchors) double mattress construct. The tendon was cycled between 10 and 100 N at 1 Hz for 100 cycles, followed by a single-cycle pull to failure at 33 mm/s. Cyclic displacement, load to clinical failure (5 mm), yield load, and mode of failure were recorded.

RESULTS

Neither construct demonstrated clinical failure under cyclic loading. Load to clinical failure was higher for the knotless repair than that of the knotted repair (788 ± 162 N vs 488 ± 227 N; P = .003). The yield load was higher for the knotless repair than that of the knotted repair (1,080 ± 298 N vs 591 ± 265 N; P = .008). The most common failure mode for the knotted repair was knot failure or tendon tearing, whereas the failure mode for the knotless repair was by anchor pull-out or tendon tear with no failures occurring via the interconnected suture construct mechanism.

CONCLUSIONS

In this biomechanical study comparing cyclic and ultimate loading for 2 double mattress remplissage repairs, the construct using interconnected, knotless sutures outperformed the knotted construct. No failure of the interconnected suture construct mechanism by slippage or breakage was observed in the knotless group.

CLINICAL RELEVANCE

The use of the interconnected knotless suture technique might improve the biomechanical strength of arthroscopic remplissage repairs in treating shoulder instability.

Return to Play and Outcomes in Baseball Players After Superior Labral Anterior-Posterior Repairs

BACKGROUND

Few studies have documented the outcomes of superior labral anterior-posterior (SLAP) repairs in baseball players. Furthermore, the results of these previous studies varied widely and were based on small numbers of patients. Hypothesis/Purpose: The purpose was to report return-to-play (RTP) rates and validated subjective outcome scores for baseball players after SLAP repair. It was hypothesized that RTP rates and outcomes would be significantly different between pitchers and nonpitchers, as well as among baseball levels.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A series of 216 baseball players was identified who had isolated SLAP repair or SLAP repair with debridement of partial-thickness (<25%) rotator cuff tear at our surgical centers. Patients were contacted by phone a minimum of 2 years after surgery and asked questions about their ability to RTP. Patients were also asked questions to complete the Western Ontario Shoulder Instability Index (WOSI), Veteran's RAND 12-Item Health Survey (VR-12), and Kerlan-Jobe Orthopaedic Clinic (KJOC) questionnaires. Statistical equivalence in RTP rate, VR-12, and WOSI scores was determined between players with and without concomitant rotator cuff debridement using 2 one-sided tests and risk difference measures. Differences in RTP were tested among baseball levels (high school, college, professional) and positions (pitcher vs nonpitcher) using chi-square analyses ( P < .05). Differences in outcomes scores were compared using t tests and analyses of variance ( P < .05).

RESULTS

Of the 216 baseball players, 133 were reached by phone for follow-up interview (mean, 78 months; range, 27-146 months). Overall, 62% successfully returned to play. There were no differences in RTP rates or subjective outcomes among baseball levels or between procedures. RTP rates were 59% for pitchers and 76% for nonpitchers ( P = .060). Subjectively, the percentage of patients who felt the same or better at follow-up compared to preinjury was significantly higher among nonpitchers (66%) than pitchers (43%). There was no difference in KJOC scores between the pitchers (75.3 ± 19.4) and nonpitchers (76.2 ± 17.4) who successfully returned to play, although these scores were well below the minimum desired score of 90 for healthy baseball players.

CONCLUSION

SLAP repair should continue to be considered as an option for SLAP tear treatment only after nonsurgical management has failed. Some players may be able to return to baseball after SLAP repair, although regaining preinjury health and performance is challenging.

Clinical outcomes after arthroscopic acetabular labral repair using knot-tying or knotless suture technique

BACKGROUND

The purpose of the study was to compare the clinical results of arthroscopic labral repair using knot-tying and knotless suture anchor techniques for patients with labral tears.

METHODS

From September 2012 to May 2013, we performed a randomized, prospective analysis of 40 hips with labral tears treated with arthroscopic labral repair via knot-tying (group A) or knotless suture anchors (group B). A total of 33 patients were treated for labral tears, and 7 of them received bilateral labral repair. Outcomes and intraoperative parameters were prospectively measured with the UCLA score, the modified Harris Hip Score (MHHS), the Hip disability and Osteoarthritis Outcome Score (HOOS), and the Hip Outcome Score (HOS).

RESULTS

Three patients (3 hips) were lost to follow up. A total of 37 hips (30 patients) were finally analyzed: 19 hips in group A and 18 in group B. The mean traction time for group A and group B was 72.2 versus 68.7 min, respectively (p = 0.314). Although the clinical outcome scores in both groups improved between the initial and final visits, there was no difference in measurements parameters between the two groups. Survival rate, using reoperation or progression of osteoarthritis as the primary end points, was 100 %. 83 % of cases had excellent and good MHHS scores after 2 years of follow-up. During arthroscopic surgery, the drill penetrated the closing subchondral area or the joint in three hips. There was no progression of arthritic change at the latest follow-up.

CONCLUSIONS

Labral repair with either knot-tying or knotless suture anchor resulted in significant postoperative improvements and no difference between the two groups after 2 years of follow-up.

Arthroscopic Knotless Repair of the Posterior Labrum Using LabralTape

Operative management of symptomatic labral tears of the shoulder has traditionally been the preferred treatment. Arthroscopic techniques and equipment continue to be refined and subsequent new recommendations for treatment are being developed. Contemporary techniques for arthroscopic knotless repair offer possible advantages over traditional arthroscopically tied knots. Although knotless repair of labral tears is well recognized, advancements continue to progress toward stronger fixation with reduced risks of cutting through the labrum and chondral abrasion. The suture tape used in the technique presented for arthroscopic knotless repair is stronger and flatter than traditional rounded suture and offers many potential benefits.

Simplified Knotless Mattress Repair of Type II SLAP Lesions

Arthroscopic repair of lesions of the superior labrum and biceps anchor has been shown to provide good to excellent results. We describe a simplified arthroscopic surgical technique using a single knotless anchor with a mattress suture configuration. This technique provides an effective and reproducible method to reattach and re-create the normal appearance of the superior labrum and biceps anchor in a time-efficient manner without the need for knot tying.

Recycling Suture Limbs from Knotless Suture Anchors for Arthroscopic Shoulder Stabilization

Recurrent shoulder instability often leads to labral abnormality that requires surgical intervention that may require fixation with suture anchors. The proposed surgical technique allows the surgeon to achieve 2 points of fixation around the labrum and/or capsule with a single suture secured to the glenoid with a knotless anchor. Instead of cutting and discarding the residual suture limbs after anchor insertion, this technique uses the residual suture limbs of the knotless anchor for a second suture pass. This technique (1) creates a more cost- and time-efficient surgical procedure than using multiple single-loaded anchors or double-loaded anchors, (2) decreases the known risk of glenoid fracture from the stress riser at the implant tips of multi-anchor repairs by reducing the number of anchors required for stabilization, (3) decreases the surgical time compared with the use of double-loaded anchors through simpler suture management and less knot tying, (4) allows for the secure reapproximation of the labrum to the glenoid while offering a convenient option for capsulorrhaphy without the need to insert another anchor, and (5) yields more points of soft-tissue fixation with fewer anchors drilled into the glenoid.

The management of type II superior labral anterior to posterior injuries

Arthroscopic repair of type II superior labral anterior to posterior (SLAP) tears is currently the standard of care, with most patients obtaining good to excellent surgical results. However, overhead athletes and older patients have inferior outcomes. Recent clinical studies and biomechanical data suggest that a biceps tenodesis is a suitable alternative in select patients. This article reviews the literature to identify the biomechanical and clinical indications for performing a biceps tenodesis for type II SLAP lesions.

Superior labral anterior posterior lesions of the shoulder

Superior labrum anterior and posterior (SLAP) lesion is of fairly recent description and its understanding is rapidly evolving. Its incidence and need for surgical treatment has increased exponentially in line with the increase in shoulder arthroscopies. It is of particular importance in the elite over head athlete and the young. A range of arthroscopic techniques and devices have been described with good functional results. The ability to return to pre injury level of sports remains a concern.

Footprint contact restoration between the biceps-labrum complex and the glenoid rim in SLAP repair: a comparative cadaveric study using pressure-sensitive film

PURPOSE

To compare pressurized footprint contact and interface pressure between the biceps-labrum complex and the superior glenoid rim after SLAP repair using 3 different techniques.

METHODS

Twenty-four fresh-frozen human cadaveric shoulders were divided into 3 groups. SLAP lesions were repaired by (1) 2 single-loaded anchors in a simple suture configuration (group T), (2) a double-loaded anchor in a simple suture configuration in a V shape (group V), or (3) a double-loaded anchor by use of a hybrid simple and mattress suture configuration (group H). Pressure-sensitive film quantified pressurized contact areas and interface pressures between the biceps-labrum complex and the glenoid rim after SLAP repair.

RESULTS

Groups T and V showed significantly larger contact areas than group H (P < .0001). However, there was no significant difference between groups T and V. Despite a substantial contact area around the biceps-labrum complex in group T, there was a lack of sufficient contact area just below the biceps anchor. Group V showed a uniform contact area around the entire biceps-labrum complex, but in group H the contact area was concentrated only around the posterior superior labrum, where the simple suture was used.

CONCLUSIONS

The methods using 2 single-loaded suture anchors and using 1 double-loaded suture anchor with a simple suture configuration showed significantly larger pressurized contact areas than the method using 1 double-loaded suture anchor with both a simple and mattress suture configuration. The interface pressure was not significantly different among groups.

CLINICAL RELEVANCE

Although there have been several kinds of repair techniques and biomechanical studies for the type II SLAP lesion, there has been no study about footprint restoration on the superior glenoid rim. This study analyzed and compared the footprint contact restoration after type II SLAP repair among 3 different techniques.

Clinical and radiological outcomes of type 2 superior labral anterior posterior repairs in elite overhead athletes

BACKGROUND

Although there are multiple reports on surgical outcomes of type 2 superior labral anterior posterior (SLAP) repairs, a literature review noted a paucity of data on clinical and radiological outcomes in elite overhead athletes.

PURPOSE

To determine midterm clinical outcomes of type 2 SLAP repairs in elite overhead athletes and whether labral integrity provides consistent return to play.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Medical records were retrospectively reviewed of 24 elite overhead athletes who underwent arthroscopic type 2 SLAP repairs. There were 18 men and 6 women, and their mean age was 22.7 years (range, 19-30 years); the majority of them (16/24) were baseball players. Four outcome measures were used: visual analog scale (VAS) for pain and satisfaction, American Shoulder and Elbow Surgeons (ASES) score, subjective feeling of recovery, and return to play. Multidetector computed tomographic arthrography was performed to evaluate labral integrity after surgery.

RESULTS

At a mean follow-up of 45.8 months (range, 24-68 months), overall pain and function improved significantly. The VAS for pain was 5.7 preoperatively and 2.0 postoperatively (P < .01), and VAS for satisfaction was 8.6. The ASES score was 55.8 preoperatively and 87.1 postoperatively (P < .01). The overall mean value of subjective feeling of recovery was approximately 76%. Twelve of 24 athletes (50%) returned to play after the operation. Although there was a trend toward higher return rate in the other overhead athletes (75%) compared with the baseball players (38%), this trend did not reach statistical significance (P = .097). Labral retear with clinical significance was noted in 2 athletes who failed to return to play. Osteolysis was observed in 2 athletes, 1 of whom had a retear. A statistical relation between the integrity of the repair and return to play was not found (P > .05).

CONCLUSION

Arthroscopic SLAP repairs show favorable clinical and radiological outcomes; however, the study findings raise a concern that return to play may still be problematic in elite baseball players. This study also indicates that labral healing does not ensure consistent return to play in elite overhead athletes.

Movement-induced knot migration after anterior stabilization in the shoulder

PURPOSE

This study compared the status of suture knots immediately after repair and after shoulder motion to evaluate the possibility of movement-induced knot migration to a location nearer the glenoid.

METHODS

We included 10 shoulders from 5 cadavers in the study. After posterior capsulotomy, a Bankart lesion was created. A capsulolabral repair was then performed with 3 knot-tying suture anchors. All knots were positioned on the capsular side, far from the articular surface. After the repair was complete, a photograph was taken with a metal rod placed to reference absolute distance. After passive pendulum motion was applied, another photograph was taken. The length of the suture strand from the knot base to the anchor insertion site was measured during both the initial repair and post-motion periods.

RESULTS

Initial distances were 4.83 ± 1.09 mm for the inferior knot, 4.70 ± 0.97 mm for the middle knot, and 3.84 ± 1.25 mm for the superior knot. After motion, the distances were 3.52 ± 1.21 mm (P = .01), 3.07 ± 0.81 mm (P < .001), and 2.69 ± 1.18 mm (P = .016), respectively. Additional observations showed changes in direction and security of the knot. The change in knot direction from an initial orientation facing the capsular side to a new orientation facing the glenoid was observed in 5 of 10 inferior, 7 of 10 middle, and 6 of 10 superior knots. In addition, knot loosening was noted for the last half-hitches in 4 inferior knots and 1 middle knot.

CONCLUSIONS

Intentional placement of suture knots away from the joint surface was not maintained after motion at the shoulder.

CLINICAL RELEVANCE

Movement-induced knot migration may be detrimental to articular cartilage in the event that a knot becomes interposed between the glenoid and humeral head.

Simple versus horizontal suture anchor repair of Bankart lesions: which better restores labral anatomy?

PURPOSE

The goal of this study was to determine which suture repair technique better restores glenoid labrum height: horizontal sutures or simple sutures.

METHODS

Sixteen cadaveric glenoids, 8 per repair technique, were used to measure native labral height at the 3:00 to 6:00 positions in half-hour increments. A Bankart lesion was then created from 3:00 to 6:30. Height measurements at each time point were again taken after creation of the Bankart lesion. Repair with a 3-mm knotted suture anchor was then performed at 3:30, 4:30, and 5:30 with either a simple or horizontal suture technique, and postrepair heights were measured across all time points.

RESULTS

Significant decreases in height, as compared with native height, were observed at 3:30, 4:30, and 5:30 in the simple repair group. Decreases in height of 1.4 mm (P = .044), 2.1 mm (P = .030), and 1.1 (P = .034) were observed at 3:30, 4:30, and 5:30. There was no significant decrease in height at these respective time points in the horizontal repair group.

CONCLUSIONS

The in vitro horizontal mattress suture technique better restores labral height and anatomy when compared with a simple suture technique in the repair of acute Bankart lesions.

CLINICAL RELEVANCE

Compared with the simple suture technique, horizontal suture repair may provide increased stability to the glenohumeral construct.

Arthroscopic suture anchor capsulorrhaphy versus labral-based suture capsulorrhaphy in a cadaveric model

PURPOSE

The purpose of this study was to establish whether suture anchor capsulorrhaphy (SAC) is biomechanically superior to suture capsulorrhaphy (SC) in the management of recurrent anterior shoulder instability without a labral avulsion.

METHODS

Twelve matched pairs of shoulders were randomized to either SC or SAC. Specimens were mounted in 60° of abduction and 90° of external rotation. Testing was conducted on an MTS servohydraulic load testing device (MTS, Eden Prairie, MN). A compressive load of 22 N was applied, followed by a 2-N anterior and posterior force to establish a 0 point. Translation with 10-N anterior and posterior loads was recorded for baseline laxity measurement. Arthroscopic capsulorrhaphy was performed with either 3 solitary sutures or 3 suture anchors. Specimens were remounted and returned to the 0 point. Translation was measured with 10-N anterior and posterior loads to determine reduction in translation. Specimens were then loaded to failure to the 0 point at a rate of 0.1 mm/s.

RESULTS

Load to failure was significantly greater (P = .02) in the SC group (13.6 ± 1.0 N) versus the SAC group (20.5 ± 2.8 N). No differences were found between SC (2.7 ± 0.7 mm) and SAC (2.3 ± 0.6 mm) when we compared reduction of anterior translation with a 10-N load. The percent reduction of anterior displacement with a 10-N load was similar for the SC (49.9%) and SAC (49.6%) groups. The dominant mode of failure in the study was suture pull-through of the capsular tissue.

CONCLUSIONS

Our study indicates that labral-based SC and SAC similarly reduce anterior glenohumeral translation at low loading conditions. Load-to-failure studies indicate that SAC exhibits significantly greater resistance to translation at higher loading conditions. Our study suggests that the use of a suture anchor when one is performing a capsulorrhaphy may provide biomechanical advantage at high loading conditions.

CLINICAL RELEVANCE

Our study suggests that when one is performing capsulorrhaphy, the use of a suture anchor may provide biomechanical advantages at high loading conditions.

Tissue anchor use in arthroscopic glenohumeral surgery

Arthroscopic surgery has become the mainstay of treatment of several common glenohumeral pathologies such as tears of the rotator cuff and labrum. Arthroscopic rotator cuff and labral repair provide outcomes comparable to those achieved with traditional open techniques, with the benefits of smaller incisions and less soft-tissue disruption. Development and improvement of tissue anchors and arthroscopic instrumentation has been integral to the increased popularity of arthroscopic glenohumeral repairs. Current anchors can be categorized by design and material composition. Awareness of the advantages and limitations of these implants may influence anchor selection.

Restoration of labral anatomy and biomechanics after superior labral anterior-posterior repair: comparison of mattress versus simple technique

BACKGROUND

Both simple and mattress repair techniques have been utilized with success for type II superior labral anterior-posterior (SLAP) lesions; however, direct anatomic and biomechanical comparisons of these techniques have yet to be clearly demonstrated.

HYPOTHESIS

For type II SLAP lesions, the mattress suture repair technique will result in greater labral height and better position on the glenoid face and exhibit stronger biomechanical characteristics, when cyclically loaded and loaded to failure through the biceps, compared with the simple suture repair technique.

STUDY DESIGN

Controlled laboratory study.

METHODS

Six matched pairs of cadaveric shoulders were dissected, and a clock face was created on the glenoid from 9 o'clock (posterior) to 3 o'clock (anterior). For the intact specimen, labral height and labral distance from the glenoid edge were measured using a MicroScribe. A SLAP lesion was then created from 10 o'clock to 2 o'clock. Lesions were repaired with two 3.0-mm BioSuture-Tak anchors placed at 11 o'clock and 1 o'clock. For each pair, a mattress repair was used for one shoulder, and a simple repair was used for the contralateral shoulder. After repair, labral height and labral distance from the glenoid edge were again measured. The specimens were then cyclically loaded and loaded to failure through the biceps using an Instron machine. A paired t test was used for statistical analysis.

RESULTS

After mattress repair, a significant increase in labral height occurred compared with intact from 2.5 ± 0.3 mm to 4.3 ± 0.3 mm at 11 o'clock (P = .013), 2.7 ± 0.5 mm to 4.2 ± 0.7 mm at 12:30 o'clock (P = .007), 3.1 ± 0.5 mm to 4.2 ± 0.7 mm at 1 o'clock (P = .006), and 2.8 ± 0.7 mm to 3.7 ± 0.8 mm at 1:30 o'clock (P = .037). There was no significant difference in labral height between the intact condition and after simple repair at any clock face position. Labral height was significantly increased in the mattress repairs compared with simple repairs at 11 o'clock (mean difference, 2.0 mm; P = .008) and 12:30 o'clock (mean difference, 1.3 mm; P = .044). Labral distance from the glenoid edge was not significantly different between techniques. No difference was observed between the mattress and simple repair techniques for all biomechanical parameters, except the simple technique had a higher load and energy absorbed at 2-mm displacement.

CONCLUSION

The mattress technique created a greater labral height while maintaining similar biomechanical characteristics compared with the simple repair, with the exception of load and energy absorbed at 2-mm displacement, which was increased for the simple technique.

CLINICAL RELEVANCE

Mattress repair for type II SLAP lesions creates a higher labral bumper compared with simple repairs, while both techniques resulted in similar biomechanical characteristics.

MRI assessment of the structural labrum integrity after Bankart repair using knotless bio-anchors

PURPOSE

Adequate labral restorations after Bankart repair have been demonstrated in cadaver models for knot-tying and knotless anchors and in vivo by magnetic resonance imaging for knot tying. The influence of glenoidal bio-degradation on clinical outcome, and conclusions regarding drill hole enlargement and foreign body reactions remain controversial.

METHODS

The labrum was analyzed in magnetic resonance images for 37 consecutive patients with Bankart repair using knotless PLLA anchors and for 31 volunteers as radiologic controls. The labrum was assessed regarding slope, height index (quotient between labral height to the glenoid height), and labrum morphology in axial and coronal T2 images. Glenoidal bio-degradation was graded in terms of the drill hole configuration in T1 images and the corresponding osseous reaction in T2 images. Constant-Murley, Walch-Duplay, and Rowe scoring were carried out preoperatively and at follow-up.

RESULTS

At 15 months after arthroscopy, the anterior slope (24.8°), height index (3.0), inferior slope (25.4°), and height index (2.5) were not significantly different from control values. Morphologic analysis revealed significant changes in the Bankart group (P < 0.05) that were influenced by the number of preoperative dislocations. Bio-degradation proceeded slowly with no evidence of drill hole enlargement. Osseous reactions were significantly greater in inferior compared to superior implants. The clinical scores were excellent and were not influenced by bio-degradation.

CONCLUSIONS

Knotless anchors facilitate labral restoration that is comparable to the knot-tying approach. Bio-degradation proceeds slowly without clinical or radiologic evidence of foreign body reactions.

LEVEL OF EVIDENCE

III.

Arthroscopic rotator cuff repair: suture anchor properties, modes of failure and technical considerations

Rotator cuff injury and tears are a common source of shoulder pain, particularly among the elderly. Arthroscopic repair has now become the mainstay in the treatment of significant injuries that have failed conservative therapy. Compared with the traditional open technique, arthroscopic repair offers patients smaller incisions and less soft-tissue trauma, which result in improved postoperative pain and rehabilitation. The advances that have made arthroscopic repairs a reality includes improvement in arthroscopic rotator cuff instrumentation, particularly suture anchors. Suture anchors are used to reattach the torn rotator cuff tissue back onto the bone. Current rotator cuff anchors vary by design, anchor composition and suture materials. A treating physician should be aware of the advantages and limitations of these implants, which may influence the choice of one anchor over another. In addition to anchor variables, other factors that may affect the success of the repair include the local environment and surgical technique. In this article, various aspects of anchor design will be discussed. In addition, a concise review of technical considerations will also be discussed.

Biomechanical analysis of pullout strengths of rotator cuff and glenoid anchors: 2011 update

PURPOSE

To evaluate the biomechanical and design characteristics of newer suture anchors.

METHODS

Suture anchors were tested in fresh porcine metaphyseal cortex and cancellous troughs by use of an established protocol. A mechanical testing machine applied tensile loads parallel to the axis of insertion at 12.5 mm/s until failure, and mean anchor failure strengths were calculated. The mode of failure was recorded. Rotator cuff anchors tested included the Doubleplay and Opus SpeedScrew (ArthroCare Sports Medicine, Sunnyvale, CA); PEEK Intraline and PEEK Zip (Stryker, San Jose, CA); Paladin, SuperRevo FT, and CrossFT (ConMed Linvatec, Largo, FL); Piton (Tornier, Warsaw, IN); Ti Screw, ALLthread PEEK, LactoScrew, ALLthread Ti, and ALLthread PEEK knotless (Biomet Sports Medicine, Warsaw, IN). Glenoid anchors included the Gryphon BR P (DePuy-Mitek, Raynham, MA) and JuggerKnot 1.4 (Biomet Sports Medicine).

RESULTS

Mean cortical failure loads for cuff anchors were as follows: Doubleplay 5.0, 279 N; Doubleplay 6.5, 338 N; Opus SpeedScrew 5.5, 356 N; Opus SpeedScrew 6.5, 336 N; PEEK Intraline 5.5, 263 N; PEEK Intraline 6.5, 344 N; PEEK Zip 5.5, 435 N; PEEK Zip 6.5, 502 N; Paladin 5.0, 500 N; Paladin 6.5, 521 N; SuperRevo FT, 496 N; CrossFT, 569 N; Piton, 379 N; Ti Screw 5.0, 457 N; Ti Screw 6.5, 443 N; ALLthread PEEK 5.5, 476 N; LactoScrew 5.5, 403 N; ALLthread Ti 5.0, 526 N; ALLthread Ti 6.5, 653 N; and ALLthread PEEK knotless, 441 N). Mean cortical failure loads for glenoid anchors were 161 N for Gryphon BR P and 239 N for JuggerKnot 1.4. Mean cancellous bone failure loads for cuff anchors were Doubleplay 5.0, 263 N; Doubleplay 6.5, 340 N; Opus SpeedScrew 5.5, 356 N; Opus SpeedScrew 6.5, 344 N; PEEK Intraline 5.5, 274 N; PEEK Intraline 6.5, 327 N; PEEK Zip 5.5, 401 N; PEEK Zip 6.5, 396 N; Paladin 5.0, 427 N; Paladin 6.5, 491 N; SuperRevo FT, 483 N; CrossFT, 547 N; Piton, 365 N; Ti Screw 5.0, 420 N; Ti Screw 6.5, 448 N; ALLthread PEEK 5.5, 475 N; LactoScrew 5.5, 435 N; ALLthread Ti 5.0, 512 N; ALLthread Ti 6.5, 612 N; and ALLthread PEEK knotless, 466 N). Mean cancellous failure loads for glenoid anchors were 117 N for Gryphon BR P and 194 N for JuggerKnot 1.4. None of the anchors had pullout as the predominant failure mode. Eyelet failure was the predominant failure mode for Doubleplay, Opus SpeedScrew, PEEK Intraline, Gryphon BR P, ALLthread Ti 6.5, ALLthread PEEK 5.5, and LactoScrew.

CONCLUSIONS

Failure load was not dependent on anchor location (cancellous or cortical bone) (P = .58) but was dependent on anchor type (cuff anchor or glenoid anchor) (P < .001).

CLINICAL RELEVANCE

Whereas larger fully threaded screw anchors designed for rotator cuff repair showed higher failure strengths than smaller non-screw anchors designed for glenoid repairs (P < .05), the larger version of a screw anchor for a cuff repair did not provide a statistically greater failure load than the smaller screw anchor.