Suture Anchors Research Articles

Arthroscopic Suprapectoral Biceps Tenodesis Using Standard Portals

The long head of the biceps (LHB) tendon is a common cause of shoulder pain. Biceps tenodesis is commonly used to address biceps and superior labrum pathology, reducing pain and restoring function. There are numerous techniques for biceps tenodesis, and it is unclear as to which single technique and approach provides significantly superior outcomes. In this technical note, we present an arthroscopic suprapectoral approach with release of the LHB from the bicipital groove and subsequent fixation with suture anchor. This technique simplifies the technique to be performed from standard arthroscopic portals and aims to maximize outcomes and minimize common complications associated with biceps tenodesis.

Rotator Cuff Repair with Knotless All-Suture Medial Row Anchors and Biceps Autograft Augmentation

Incomplete healing and/or functional failure following rotator cuff tear repair remains a challenging problem for both patients and surgeons. Augmentation strategies are growing to increase healing through biologic and mechanical mechanisms to improve functional results after arthroscopic rotator cuff repair. The majority of currently described augmentation techniques use allograft tissue. An alternative, low-cost, autograft option for augmentation is the use of the long head of biceps tendon autograft as a free functional graft. Here, we describe the use of autograft biceps tendon as a viable option for augmentation of double-row rotator cuff repair with knotless all-suture suture anchors.

“Make and Use” All Suture Anchor—A Cost-Effective Method of Making an All-Suture Anchor

All-suture anchors (ASA) are newer anchors that anchor soft tissues to the bone. It has several biomechanical and clinical advantages; however, the high cost of this anchor limits its use in low socioeconomic countries. The cost of the anchor dramatically increases the cost of surgery; hence, acceptance of surgery is also affected if patients have to pay their expenditure from their pocket. We have designed a simple, cost-effective method of making an ASA, which can be made instantly and used during surgery; hence, the name “make-and-use anchor.” To make this anchor, few high-strength sutures are required. Over the suture, a sleeve of suture was created using an Ethibond. This sleeve will create a “ball” after deployment under the cortical bone, which provides anchorage to the sutures serving as an anchor. This anchor can be deployed both in the pull-in and push-in methods. This technical note aims to share the technique of making this cost-effective anchor, which is made instantly using locally available suture materials and can be used in various surgeries requiring anchors.

An All-Suture Anchor Offers Equivalent Clinical Performance to an Established Solid Suture Anchor in the Arthroscopic Repair of Rotator Cuff Tears: A Prospective, Randomized, Multicenter Trial With 12-Month Follow-Up

To evaluate the safety and efficacy of a next-generation, all-suture anchor in patients undergoing arthroscopic repair of rotator cuff tears, compared with that of an established solid suture anchor. Between April 2019 and January 2021, a prospective, comparative, randomized controlled noninferiority study conducted on people with Chinese ethnicity at 3 tertiary hospitals enrolled patients (18-75 years) requiring arthroscopic treatment for rotator cuff tears. Patients were randomized into 2 cohorts receiving either all-suture anchor or solid suture anchor and followed for 12 months. The primary outcome was the Constant-Murley score at the 12-month follow-up. Magnetic resonance imaging assessments determined the rate of retear of rotator cuff repair (defined as Sugaya classification 4 and 5). Safety evaluation was performed at all follow-up points to determine the adverse events (AEs). In total, 120 patients with rotator cuff tears (mean age, 58.3 years; 62.5% female; 60 receiving all-suture anchor) underwent treatment. Five patients were lost to follow-up. Both cohorts showed significant improvement in Constant-Murley scores between baseline and 6 months (P < .001) and between 6 and 12 months (P < .001). There were no significant differences in Constant-Murley scores between the 2 cohorts at 12 months (P= .122) after operation. The retear rate at 12 months was 5.7% and 1.9% in the all-suture and solid suture anchor cohorts, respectively (P= .618). There were 2 cases of intraoperative anchor pullout, both of which were successfully resolved. No cases of postoperative reoperation or other anchor-related AEs were reported. The all-suture anchor offered equivalent clinical performance to an established solid suture anchor at the 12-month follow-up in patients undergoing arthroscopic repair of rotator cuff tears. The retear rate was not statistically significantly different between the 2 cohorts. Level I, randomized controlled trial.

A biomechanical study to optimize superior capsular reconstruction operative technique

The goals of this study were to optimize superior capsular reconstruction by assessing the relative fixation strength of 4 suture anchors; evaluating 3 glenoid neck locations for fixation strength and bone mineral density (BMD); determining if there is a correlation between BMD and fixation strength; and determining which portal sites have optimal access to the posterosuperior and anterosuperior glenoid neck for anchor placement. Twenty cadaveric specimens were randomized into 4 groups: all-suture anchor (FiberTak), conventional 3.0-mm knotless suture anchor (SutureTak), 3.9-mm knotless PEEK (polyetheretherketone) Corkscrew anchor, and 4.5-mm Bio-Corkscrew anchor. Each specimen was prepared with 3 anchors into the glenoid: an anterosuperior anchor, superior anchor, and posterosuperior anchor. All anchors were inserted into the superior glenoid neck 5 mm from the glenoid rim. A materials testing system performed cyclic testing (250 cycles) followed by load-to-failure testing at 12.5 mm/s. Cyclic elongation, first cycle excursion, maximum load, and stiffness were recorded. Using custom software, BMD was calculated at each anchor location. This software was also used to assess access to the posterosuperior and anterosuperior glenoid neck from standard arthroscopic portal positions. There was no significant difference in cyclic elongation (P=.546), first cycle excursion (P=.476), maximum load (P=.817), or stiffness (P=.309) among glenoid anchor positions. Cyclic elongation was significantly longer in the PEEK Corkscrew group relative to the other implants (P≤.002). First cycle excursion was significantly greater in the FiberTak group relative to all other implants (P≤.008). For load-to-failure testing, the Bio-Corkscrew group achieved the highest maximum load (P≤.001). No other differences in cyclic or failure testing were observed between the groups. No differences in stiffness testing were observed (P=.133). The superior glenoid rim had the greatest BMD (P=.003), but there was no correlation between BMD and cyclic/load outcomes. The posterior portal (80% of specimens) and the anterior portal (60% of specimens) demonstrated the best access to the posterosuperior and anterosuperior glenoid neck, respectively. The 4.5-mm Bio-Corkscrew anchor provided the most robust fixation to the glenoid during superior capsular reconstruction as it demonstrated the strongest maximum load, had minimal elongation, had minimal first cycle excursion, and did not fail during cyclic testing. The superior glenoid neck had the highest BMD; however, there was no correlation between BMD or glenoid anchor location and biomechanical outcomes. The posterior portal and anterior portal provided optimal access to the posterosuperior glenoid neck and anterosuperior glenoid neck, respectively.

Poster 111: Biomechanical Analysis of Anteroinferior Bankart Repair Anchor Types: Has Technology Surpassed Surgeon Technique?

Objectives: To limit risk of recurrent dislocation, subsequent injury, and more complex surgeries, it is critical to understand the best techniques to repair a soft-tissue Bankart lesion in the setting of minimal bone loss. To the authors’ knowledge, there is no current biomechanical data comparing tensionable knotless all-suture anchors to knotted all-suture anchors and hardbody knotless anchors in labral repair constructs. Therefore, the purpose of this study was to perform a quantitative biomechanical comparison of three labral fixation devices for soft-tissue Bankart lesions: soft body tensionable knotless anchor (SB knotless), knotted soft body anchor (SB knotted), knotless interference polyetheretherketone (PEEK) hardbody anchor (HB knotless). The authors hypothesized that the three anchor types would exhibit similar biomechanical properties including elongation, failure load, and stiffness but that the SB knotless would display different failure mechanisms from the SB knotted and HB knotless anchors. Methods: Twenty-one glenoid cadavers were randomized to 3 groups: SB knotless (Arthrex 1.8mm FiberTak Knotless All-suture Anchor), SB knotted (Arthrex 1.8mm FiberTak Knotted single loaded All- Suture Anchor), and HB knotless (Arthrex 2.9mm PushLock Knotless PEEK anchor). The humeral head was disarticulated and artificial Bankart lesions were created at the anteroinferior (AI) labrum. Anchors were placed at the 3:30, 4:30, and 5:30 positions, and sutures were passed through 1cm of tissue (Figure 1). Knotted anchors were tied with five square knots. Anchors were tested simultaneously as one construct by pulling the capsular tissue connected to the AI quadrant. Cyclic loading (5-25 N, 100 cycles) was followed by load-to-failure testing (15mm/min). Mechanical testing variables were collected, and failure mechanisms were recorded per individual anchor. Statistical comparisons were made among groups including ANOVA for normally-distributed continuous variables, Kruskal-Wallis for non- parametric continuous variables, and Fisher’s Exact test for categorical variables. Results: There were no significant differences among groups in cadaveric age (p = 0.43), body mass index (p = 0.42), bone mineral density (p = 0.84), laterality (p = 0.26), or sex (p = 0.098). There was no significant difference between groups in cyclic elongation measured from the first to last cycle during cyclic loading (p = 0.40). Ultimate load to failure between SB knotless (309.7 ± 125.6 N), SB knotted (226.40 ± 34.8 N), and HB knotless (256.5 ± 90.5 N) did not significantly differ (p = 0.25) (Table 1). Failure mechanisms significantly differed among groups; mechanisms included anchor pull-out (SB knotless 33.3%; SB knotted 23.8%; HB knotless 28.6%), suture pull-through (SB knotless 66.7%; SB knotted 38.1%; HB knotless 33.3%), and anchor fixation failure, defined as knot failure for knotted anchors or locking mechanism failure for knotless anchors (SB knotless 0%; SB knotted 38.1%; HB knotless 38.1%, p = 0.008) (Figure 2). Conclusions: The SB knotless, SB knotted, and HB knotless labral fixation anchors studied exhibit comparable elongation during cyclic loading, stiffness, and ultimate loads to failure. However, the SB knotless anchor avoids the risk of knot failure and interference failure inherent to SB knotted and HB knotless interference anchors, respectively. This data supports the benefit of SB knotless anchors for anteroinferior labral repair in limiting knot failure seen with knotted anchors and perhaps demonstrating that all- suture anchors may have better locking mechanism quality than their PEEK counterpart. How and if these mechanical properties of the anchors correlate with clinical results for soft-tissue Bankart repair requires further investigation, and likely one with high power from multi- center studies to detect if subtle differences exist. [Table: see text]

Poster 143: Patella Fixation Using All-Suture Versus Knotted and Knotless Solid Suture Anchors in Medial Patellofemoral Ligament Reconstruction: A Biomechanical Analysis

Objectives: Patients with recurrent patellofemoral instability are indicated for medial patellofemoral ligament (MPFL) reconstruction. Multiple different patellar graft fixation methods exist in MPFL reconstruction surgery, namely bone tunnels, interference screws, and suture anchors. Meta analysis has shown suture patellar fixation to have superior patient reported outcomes with no statistical difference in failure rates when compared to transpatellar tunnel fixation clinically. Amongst suture anchor designs, all-soft-suture anchors occupy a smaller volume than solid suture anchors, requiring a smaller diameter tunnel during placement and thus theoretically can reduce the risk of patella fracture and articular surface violation. However, there is concern that all-soft-suture anchors may be biomechanically inferior to their hard-bodied anchor counterparts. Additionally, there is a paucity of research comparing different anchor designs (knotted vs knotless) amongst hard-bodied anchors in the setting of MPFL reconstruction. The purpose of this study is to perform a biomechanical comparison of newer generation soft-bodied anchors and hard-bodied suture anchors with different fixation methods when performing an osseous-based MPFL reconstruction in a cadaveric model. Methods: Fourteen patellae were randomized into three groups: PEEK hard-body knotless (HB-knotless), PEEK hard-body knotted (HB-knotted), and soft-body knotless (SB-knotless) anchors placed at the anatomic MPFL insertions in the direct medial position and at the superomedial aspect of each patella. Prior to anchor placement, bone density at the sites of anatomic MPFL insertions was measured on standard radiographs. After anchor placement, patellae were potted, and anchors were tested in a materials test system in a cyclic regimen (10-30 N, 100 cycles) immediately followed by load-to-failure (6mm/sec). All testing was performed in line with the anchor alignment (Figure 1). Outcome measures included maximum load and cyclic creep, defined as the difference in segment length from the peak load of the first cycle to the peak load of the 100th cycle of testing. One-way ANOVA and Fisher exact tests were used to evaluate outcomes between groups. Statistical significance was set at p &lt; 0.05. Results: Analysis included 6 SB-knotless, 14 HB-knotted, and 8 HB-knotless anchors. The groups were equivalent in age (range 30 years – 70 years; p = 0.657) and bone density (p = 0.134) in a 4:3 male-to- female ratio. There was no significant difference in cyclic creep detected between SB-knotless (3.00 ± 0.79 mm), HB- knotless (2.80 ± 0.42 mm), and HB-knotted (3.25mm ± 0.70 mm) groups (p = 0.301). HB-knotted exhibited a lower maximum load (111.30 ± 43.71 N) than HB-knotless (180.01 ± 58.87 N) (p = 0.017), but no significant difference to SB-knotless (149.34 ± 61.38 N) (p = 0.310) (Figure 2). HB- knotless and SB-knotless did not have a significant difference in maximum load (p = 0.529). When evaluating the influence of patellar anchor site on performance, there was no significant difference in cyclic creep or maximum load between direct medial and superomedial anchor positioning in SB-Knotless (p = 0.800, p = 0.800), HB-Knotted (p = 0.719, p = 0.219), or HB-Knotless (p = 0.886, p = 0.057) groups, respectively. There were 6 SB-knotless, 12 HB-knotted, and 7 HB-knotless anchors that failed by anchor pull-out, with 2 HB-knotted and 1 HB-knotless which failed either by the suture breaking within the anchor or the knot failing (Figure 3). This difference between failure mechanisms was not significant. Conclusions: Hard-body knotless anchors provide superior load to failure than traditional hardbody knotted anchors. Additionally, all-soft-suture anchors performed as well as their counterparts in both load to failure and resistance to cyclic creep. This work suggests surgeons should be comfortable using either hard-body or all-soft-suture anchors when performing osseous-based MPFL reconstructions and may consider opting for a knotless mechanism when utilizing a PEEK hard-bodied anchor for this purpose. A clinical study should take place next to validate these cadaveric findings.

A Case Series of Repair Using a Cost-effective Suture Anchor for Upper Limb Surgeries

Abstract Objective: The purpose of this study is to focus on various cases which were operated using an affordable suture anchor for soft-tissue bone repairs of upper limb surgeries in our series of patients. Study Design: Case series; Level of evidence, 4. Materials and Methods: Eighteen patients with minimum 1-year follow-up after various upper limb surgeries using modified suture anchor were assessed both clinically and radiographically. The Visual Analog Scale (VAS) was used to assess the intensity of pain. We used the disabilities of arm, shoulder, and hand (DASH) to assess the functional outcome. Results: VAS score improved from 5.39 ± 1.85 at 1-month postoperative period to 0.45 ± 0.51 at 12 months (P &lt; 0.05). DASH score improved from 47 ± 18.99 at 1-month postoperative period to 8.89 ± 4.98 at 12 months (P &lt; 0.05). There was no incidence of breakage of suture material or loosening of the implant seen during the insertion. There were no complications related to the implant noted. Conclusion: Clinical failures did not occur in this group of 18 patients undergoing repair using modified suture anchor. Following soft tissue-to-bone fixation, patients showed excellent short-term clinical and radiographic outcomes. This innovative method is quick, simple, inexpensive, repeatable, and saves time by transforming a basic screw and suture material into an effective suture anchor.

Concomitant Medial Meniscal Root Repair with Extrusion Repair (Centralization Technique).

Concomitant Medial Meniscal Root Repair with Extrusion Repair (Centralization Technique).

Original surgical technique for the treatment of patellofemoral instability after failure of conservative treatment

IntroductionAcute patellar dislocation is a common but serious injury that can significantly impact a patient's functional prognosis. The objective of this retrospective study is to evaluate the clinical outcomes of arthroscopic medial patellofemoral ligament (MPFL) reconstruction and plication of the medial patellar retinaculum using suture anchors in adolescent patients with first-time acute patellar dislocation (APD) and MPFL insertion injury. HypothesisTightening repair of the medial retinaculum complex can result in favorable clinical and functional outcomes in this patient population. Materials and methodsA total of 84 adolescent patients with first-time APD and with an average age of 15.5 years (10-22) were included in the study. Of these patients, 61 (7 male and 54 female) underwent arthroscopic suture anchor plication for medial patellar retinaculum, while the other 23 were successfully treated non-operatively. Radiographic outcomes, including the congruence angle (CA), lateral patellofemoral angle (LPA), and patellar tilt angle (PTA), were evaluated preoperatively and at the last follow-up visit in the surgical group. Functional outcomes were assessed using the Lille Patello-Femoral Score, Lysholm Score, and Kujala Score at the same time points. In addition, the surgical and non-operative treatment success groups were compared in terms of both radiographic and functional outcomes. ResultsMean follow-up was 40.9 months (24–60). Fifty-nine knees showed excellent or good results postoperatively, 2 patients had a recurrent patellar subluxation. The Lille Patello-Femoral Score was 96.9±4.7 at the last follow-up. The subjective Lysholm Score and Kujala Score improved significantly, from 58.6 to 91.9 and from 60.4 to 88.9, respectively. The radiographic CA, LPA and PTA improved significantly, from 19.8±2.1° to –6.7±1.7°, from –7.4±2.2° to 5.7±1.8° and from 23.8±2.9° to 12.3±2.3°, respectively. There was no statistically significant difference in functional and radiographic assessments between the success with non-operative treatment group and the surgery group. ConclusionThe results of this study suggest that arthroscopic MPFL insertion reconstruction and plication using suture anchors, which is less invasive and improves patella stability, can lead to favorable clinical and functional outcomes in adolescent patients with first-time acute patellar dislocation and insertion injury. This treatment approach should be considered as a viable option for this patient population. Level of evidenceIV; monocentric retrospective descriptive study.

Pectoralis Major Tendon Transfer for Subscapularis Insufficiency: An Operative Technique

Background: Pectoralis major tendon (PMT) transfer is an effective surgical treatment for addressing subscapularis insufficiency in younger, active patients. Indications: The primary indication for a PMT transfer is subscapularis insufficiency or irreparable tear in an active, young patient that is not a candidate for reverse shoulder arthroplasty. In addition, patients should have an intact posterosuperior rotator cuff. In this case, the patient is a 41-year-old male with chronic anterior shoulder instability after failed open Bankart stabilization with subscapularis incompetency. Technique Description: The patient was placed in the beach-chair position and a standard deltopectoral approach was utilized. The conjoint tendon and adjacent musculocutaneous nerve were identified and retracted. Subsequently, the sternal head of the PMT was isolated from the clavicular head at the humeral insertion. It was then released, mobilized and passed inferior to the conjoined tendon for reapproximation at the lesser tuberosity with a suture anchor. Results: A previous systematic review demonstrated that patients with isolated subscapularis insufficiency who undergo PMT transfer have significant increase in Constant Score, range of motion, and internal rotation strength. Additionally, a retrospective case series evaluating 22 patients at a 10-year follow-up revealed maintained improvements in Constant Score, Simple Shoulder test, and Visual Analog scale for Pain. However, they found that strength on internal rotation and range of motion significantly regressed to baseline, preoperative levels. Discussion/Conclusion: PMT transfer for subscapularis insufficiency is a viable treatment option for symptomatic subscapularis tendon tears not amenable to repair. It allows for excellent long-term improvements in strength, range of motion and patient reported outcomes. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Arthroscopic Repair of an Anteroinferior Capsular Tear in the Shoulder of a Throwing Athlete

Background: Anterior capsular tears are often associated with traumatic glenohumeral instability episodes; however, there are not many previous descriptions in the literature without occurrence of frank dislocation. This video will discuss the presentation of a throwing athlete with an anteroinferior capsular tear in his dominant shoulder who underwent successful arthroscopic repair. Indications: Based on the patient's clinical symptoms, magnetic resonance imaging arthrogram findings, and failure to return to play despite attempts at conservative management, he was determined to be a candidate for arthroscopic repair. Technique Description: Arthroscopic repair consisted of reapproximation of the avulsed capsular tissue to its attachment point medially using suture anchors in the glenoid and a side-to-side repair of the mid-substance extension of the capsular split. Results: Arthroscopic repair of the anteroinferior capsular tear allowed the patient to return to his previous level of sport. Discussion/Conclusion: In the present case and a previous case series, surgical repair of anterior capsular tears, whether arthroscopic or open, can yield good results in throwing athletes aiming to return to prior levels of performance. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Paper 03: The Anterior Labral Circumferential Onlay Technique (ALCOT) serves to reconstruct the anterior labrum and biomechanically restores anterior glenohumeral joint stability

Objectives: The standard of care for treating anterior shoulder instability caused by a labral detachment is the Bankart repair. In the case of a deficient labrum with significant antero-inferior glenoid bone loss, the latarjet technique can be used instead. However, when the labrum is deficient and the bone loss is minimal, labral reconstruction has been recently proposed as an alternative. A new technique called Anterior Labral Circumferential Onlay Technique (ALCOT) was developed, which reconstructs the labrum using the long head of the biceps tendon. The purpose of this study was to biomechanically evaluate the efficacy of the ALCOT to stabilize the shoulder joint against anterior dislocation in the setting of a deficient labrum with no glenoid bone loss. Methods: Ten fresh-frozen cadaveric shoulders were tested in 5 consecutive states using a 6-degrees-of-freedom robotic arm: (1) Native, (2) Capsular Repair, (3) Labral Tear (4) ALCOT (5) Latarjet. The capsule repair state used as a control because the joint capsule needed to be opened and repaired to perform the other states. This state ensured that any differences were due to the surgical procedure being tested, and not because of any iatrogenic damage to the capsule. The Labral Tear was performed by detaching the labrum from the glenoid between 3-6 o’clock and removing it from the joint. For the ALCOT, the biceps tendon was shortened at the distal portion and pulled into the joint. Three knotless all suture anchors were placed at 3, 4:30 and 6 o’clock position on the glenoid rim, and the biceps tendon was secured to the suture anchors using mattress stitches. For the latarjet, a coracoid autograft was cut 25 mm from the tip, keeping the conjoint tendons intact, and secured to the glenoid using two screws. In the native state, each specimen underwent an initial test to determine the appropriate amount of anterior and inferior displacement for future tests. In this test, a 50N compressive load was maintained while an 80N force was applied in the sagittal plane at a 45° angle between the anterior and inferior axes. The corresponding anterior and inferior displacements were recorded. Then, in each state including native, a dislocation test was performed. In this test, a 50N compressive load was maintained while the joint was driven in position control to the previously recorded positions on the anterior and inferior axes. The amount of force needed to displace the shoulder and the lateral displacement of the humeral head were recorded throughout the motion. Higher lateral translation was considered more stable, because it corresponded to a larger obstacle to overcome during the dislocation. To account for variation in the amount of compressive load during the test, antero-inferior dislocation load was normalized by compressive load to create a force ratio. This metric accounts for the fact that the amount of force required to dislocate depends on the amount of stabilizing compressive load provided by the robot in vitro, and by muscle tension in vivo. Results: No significant differences were found between the native and capsular repair states. Compared to native, the labral tear significantly decreased the lateral translation of the humeral head during dislocation from 6.5mm to 5.4mm (p&lt;0.001) and decreased the force ratio from 1.8 to 1.1 (p=0.002), corresponding to a decrease from 90N to 55N at 50N of compressive load. The ALCOT restored these values to 6.4 mm and 1.4, respectively, showing no significant difference from native. The latarjet restored the force ratio to 1.3 (not significant from native) but failed to restore lateral translation with a value of 5.6 mm (p=0.003 from Native, not significantly different from the labral tear). The force ratio is shown on figure 1 and the lateral translation is shown on figure 2. Conclusions: The ALCOT is a novel technique for labral reconstruction that can be considered as a treatment option for anterior instability in the setting of a deficient labrum. Compared to the latarjet technique, the ALCOT involves less morbidity and represents a more anatomic glenoid surface by replacing the labrum without changing the bony morphology. In this study, the ALCOT also showed superior stabilization by restoring native force ratio and lateral humerus translation. Further research is necessary to clinically validate this technique, and possibly to expand indications to small degrees of glenoid bone loss. [Table: see text]

Poster 107: Biomechanical Effect of “AIGHL Reconstruction” for Bankart Lesion in Thrower’s Shoulder: A Novel Surgical Treatment to Maintain Maximum Shoulder External Rotation Angle after Surgery

Objectives: For anterior shoulder instability, antero-inferior labral repair (Bankart repair) is a reliable surgery to prevent shoulder dislocation. However, in biomechanical and clinical studies, maximum shoulder external rotation angle is reported to be decreased by about 10 degrees due to shortening of the anterior band of the inferior glenohumeral ligament (AIGHL) length after Bankart repair. For overhead throwing athletes, the 10 degrees reduction in shoulder external rotation makes it difficult to return to the previous performance level, although it does not affect daily activity. To prevent shortening of the AIGHL length, an AIGHL reconstruction was developed using fascia lata graft. Preliminary clinical results in overhead throwing athletes showed that a throwing program could start with complete restoration of maximum shoulder external rotation angle 3 months after AIGHL reconstruction. In this study the effect of AIGHL reconstruction on shoulder external rotation and anterior stability for simulated Bankart lesion in a cadaveric model of a thrower’s shoulder was evaluated (Fig. 1). Methods: Eight cadaveric shoulders were tested at 60° of glenohumeral abduction (90° of shoulder abduction) to simulate throwing motion. Glenohumeral translations at 60° and 90° of external rotation, maximum humeral rotational range of motion, and humeral head shift were measured using goniometer and MicroScribe 3D-digitizer. Each specimen was subjected to five experimental stages: (1) intact condition; (2) simulation of thrower’s shoulder by anterior capsular stretching based on previously reported method; (3) creation of Bankart lesion (AIGHL and the labrum were detached at glenoid side); (4) Bankart repair using three suture anchors; and (5) AIGHL reconstruction using allograft of fascia lata. In the AIGHL reconstruction, allograft was patched between the detached AIGHL and glenoid at maximum shoulder external rotation position to restore the original AIGHL length (Fig. 2). For statistical analysis, linear mixed-effects model and Tukey’s post-hoc analysis were used. Results: After 20% stretching, shoulder external rotation and anterior translation were significantly increased (intact 128.3° and 2.8mm, thrower’s shoulder 141.9° and 7.3mm, p&lt;0.001). Creation of Bankart lesion significantly increased anterior translation (8.3mm) compared with intact condition (p=0.021). Bankart repair completely restored anterior translation (3.0mm) to intact level; however, maximum shoulder external rotation angle after Bankart repair (134.8°) was significantly less than that in thrower’s shoulder (p=0.009). AIGHL reconstruction completely restored anterior translation (6.5mm) to thrower’s shoulder without decreasing maximum shoulder external rotation angle (144.4°) compared with thrower’s shoulder (Fig. 3 &amp; 4). At maximum humeral external rotation, the humeral head was significantly shifted superiorly after creation of Bankart lesion compared with intact condition(p=0.005). After Bankart repair, the humeral head was significantly shifted inferiorly from the Bankart lesion (p=0.003) and was significantly inferior relative to the position after AIGHL reconstruction (p=0.007). Conclusions: While Bankart repair completely restored anterior translation to the intact level (tighter than thrower’s shoulder), AIGHL reconstruction completely restored to the thrower’s level. Furthermore, maximum shoulder external rotation angle was maintained after AIGHL reconstruction although Bankart repair decreased external rotation significantly. Therefore, AIGHL reconstruction can be a useful surgical option for Bankart lesion in overhead throwing athletes to restore anterior stability while maintaining maximum shoulder external rotation angle after surgery.

Arthroscopic Posterior Labral Repair for Posterior Shoulder Instability

Background: Posterior shoulder instability occurs in 2% to 10% of shoulder instability cases and is more commonly due to repetitive microtrauma as opposed to the more traumatic onset seen in anterior shoulder instability. In posterior instability, the posterior capsulolabral complex becomes attenuated or torn. Thus, surgical treatment aims to restore the posterior soft-tissue stabilizers typically with an arthroscopic, suture-anchor-based labral repair. Indications: Surgical indications include posterior instability with traumatic cause and associated soft-tissue and/or osseous pathology and for those patients with repetitive microtrauma who have failed nonsurgical management. Technique Description: Following diagnostic arthroscopy, the glenoid is prepared using an arthroscopic elevator, rasp, and chisel first viewing from the posterior portal, then from the anterior portal using a 70° arthroscope. An all-suture anchor is placed at the 7 o’clock position using a curved guide which obviates the need for an accessory 7 o’clock portal. The repair suture is then shuttled through the labrum using a suture lasso and monofilament. This repair suture is then shuttled through the suture anchor using the inbuilt shuttling fiberlink. The repair suture is then tightened to secure the labrum. The remainder of the repair uses knotless 2.9-mm biocomposite suture anchors and free suture tape as the all-suture anchor and associated curved guide are typically only necessary for the angle of the most inferior portal. Following a 3 to 5 anchor repair, the posterior portal capsular rent is closed to avoid leaving a stress riser. Posterior capsular closure is achieved using monofilament suture passed with a birdbeak and tied blindly in the subacromial space. Results: In a study of 200 shoulders at 36 months, patients undergoing posterior stabilization had improvements in their American Shoulder and Elbow Surgeons (ASES) scores and improvements in stability, pain and function. Ninety percent of patients were able to return to sport and 64% of patients returned to the same level. Failure rate was low at 6%. Discussion/Conclusion: Posterior labral repair is a technically nuanced but reliable procedure for the management of posterior instability. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Poster 247: Predictors of Poor Outcomes Following Quadriceps Tendon Repair

Objectives: Ruptures of the quadriceps tendon can lead to significant morbidity and are nearly always treated with surgical repair. Although relatively uncommon, they present most frequently in older adults and individuals with underlying medical conditions. Specifically, spontaneous bilateral ruptures have been shown to be associated with gout, diabetes, or steroid use. In other areas of orthopedics, factors such as an obese BMI have been shown to be predictive of poor outcomes after surgical treatment. To date, there has been little published literature to demonstrate how factors such as age, BMI, and smoking status are associated with quadriceps tendon tear or outcomes. The purpose of this study was to examine the relationship between patient factors such as age, sex, BMI, and smoking status, as well as intraoperative factors and the outcome of quadriceps tendon repair. We hypothesize that older age, higher BMI, and poor smoking habits will be associated with worse range of motion and complication rates following quadriceps tendon repair. Methods: All patients undergoing Quadriceps tendon repair from 1/1/2016-9/1/2021 were retrospectively identified at our institution using CPT codes, and patients who had definitive documentation of a quadriceps tendon tear within the operative report were included in the study. Patients under the age of 18 years were excluded. Physician clinical notes were reviewed, recording detailed information regarding the presenting symptoms and physical exam findings. Pre-operative demographic information and intraoperative findings were evaluated. Poor outcomes were defined as a need for revision, complications, post-operative range of motion (ROM) of less than 110 degrees of knee flexion, and extensor lag greater than 5 degrees. Parametric continuous data was presented as mean(SD) and p values were calculated by performing T tests. Nonparametric continuous data was also presented as mean(SD) for easier interpretation and p values were calculated by performing Mann- Whitney tests. P values less than 0.05 were deemed significant. All statistical analyses were done using R Studio (Version 4.1.2, Vienna, Austria). Results: There were 235 patients who met the inclusion criteria. Patients had an average age of 59 (13.3) years at time of surgery consistent of predominantly males (90.2%). The mean BMI for this cohort was 32.1(6.34). The most common surgical procedure was Transosseous fixation (81.5%) followed by suture anchors (16%) and simple sutures (2.6%). The most common mechanism of injury was trauma (57.6%) followed by spontaneous injury (39.8%). On post-operative physical exam, 18.4% of patients experienced loss of range of motion, 15.4% experienced extension lag, 9.52% had post-operative complications, and 4.7% underwent revision. Three sets of logistic regressions were run for subgroups of poor outcomes showing BMI (OR, 1.07, 95% CI, 1.01 – 1.14) and Age (OR, 1.05, 95% CI, 1.02 – 1.08) were significantly associated with loss of range of motion. Post-operative extension lag was also associated with greater BMI (OR, 1.63, 95% CI, 1.17 – 2.91). Complications were found to be significantly associated with patients found to have pre-operative tendon degeneration via MRI (OR, 4.74, 95% CI, 1.65 – 14.67) and those who were current smokers (OR, 7.84, 95% CI, 2.32 – 27.12). Amount of retraction, degree of pre-operative osteoarthritis, retinacular involvement, tear thickness and location were not significantly associated with poor outcomes. Conclusions: This study demonstrates that patient specific characteristics can play a significant role in outcomes following quadriceps tendon repair. Advanced age, BMI, tendon degeneration and current smokers are all at risk for poor outcomes following quadriceps tendon repair.

The Agonist-Antagonist Myoneural Interface in a Transtibial Amputation.

The agonist-antagonist myoneural interface (AMI) technique at the time of transtibial amputation involves the use of agonist-antagonist muscle pairs to restore natural contraction-stretch relationships and to improve proprioceptive feedback when utilizing a prosthetic limb1. Utilizing the standard incision for a long posterior myofasciocutaneous flap, the lateral and medial aspects of the limb are dissected, identifying and preserving the superficial peroneal and saphenous nerve, respectively. The tendons of the tibialis anterior and peroneus longus are transected distally to allow adequate length for the AMI constructs. After ligation of the anterior tibial vessels, the deep peroneal nerve is identified and tagged to create a regenerative peripheral nerve interface (RPNI). The tibia and fibula are cut approximately 15 cm from the medial joint line, facilitating dissection of the deep posterior compartment and ligation of the peroneal and posterior tibial vessels. The tendons of the lateral gastrocnemius and tibialis posterior are transected distally, and the amputation is completed. The extensor retinaculum is harvested from the residual limb along with multiple 2 × 3-cm free muscle grafts, which will be used for the RPNI constructs. The retinaculum is secured to the tibia with suture anchors, and AMI pairs of the lateral gastrocnemius and tibialis anterior as well as the tibialis posterior and peroneus longus are constructed. Separate RPNIs of the major lower-extremity nerves are performed, and the wound is closed in a standard layered fashion. An isometric myodesis of the gastrocnemius without coaptation of agonist-antagonist muscle pairs can be performed at the time of transtibial amputation. The AMI technique restores natural agonist-antagonist relationships at the time of transtibial amputation to increase proprioceptive feedback and improve prosthetic control. These outcomes contrast with those of a traditional isometric myodesis, which prevents proprioceptive communication from the residual limb musculature to the central nervous system. Additionally, the AMI technique allows for concentric and eccentric muscular contractions, which may contribute to the maintenance of limb volume and aid with prosthetic fitting, as opposed to the typical limb atrophy observed following standard transtibial amputation1,2. With the development and availability of more advanced prostheses, the AMI technique offers more precise control and increases the functionality of these innovative devices. Early clinical outcomes of the AMI technique at the time of transtibial amputation have been promising. In a case series of the first 3 patients who underwent the procedure, complications were minor and consisted of 2 episodes of cellulitis and 1 case of delayed wound healing1. Muscle activation measured through electromyography demonstrated an improved ability to limit unintended muscular co-contraction with attempted movement of the phantom limb, as compared with patients who underwent a standard transtibial amputation1. Additionally, residual limb volume was maintained postoperatively without the need for substantial prosthetic modifications. The tendons of the tibialis anterior, peroneus longus, tibialis posterior, and lateral gastrocnemius should be transected as distal as possible to allow adequate length for creation of the AMI constructs.Approximately 2 × 3-cm free muscle grafts are harvested from the amputated extremity for RPNI3.Smooth tendon-gliding through the synovial tunnels should be confirmed before closure. If necessary, muscle debulking can improve gliding and decrease the size of the residual limb.Harvesting the extensor retinaculum for synovial tunnels has been our preferred method, although we acknowledge that other grafts options such as the tarsal tunnel are available1. RPNI = regenerative peripheral nerve interfaceAMI = agonist-antagonist myoneural interfaceEMG = electromyographic.

Paper 51: A Radiostereometric Analysis of Tendon Migration following Arthroscopic and Mini-Open Biceps Tenodesis: Interference Screw confers Greater Construct Stability than All-Suture Suture Anchor Fixation, with No Difference in Patient-Reported Outcomes

Objectives: To quantify the postoperative migration of the BT construct between arthroscopic suprapectoral (ASPBT) and open subpectoral (OSPBT) techniques via interference screw (IS) or all-suture anchor with a single suture (SSSA) fixation with radiostereometric analysis (RSA). Methods: Distal migration of the biceps tendon following OSPBT with a Polyetheretherketone (PEEK) IS, OSPBT with one SSSA, ASPBT with PEEK IS, and ASPBT with two SSSAs was measured prospectively. Patients with symptomatic biceps tendinopathy and preoperative Patient-Reported Outcome Measures (PROMs) including CMS, SANE, or PROMIS-UE scores were included. A tantalum bead was sutured on the proximal end of the long head biceps tendon before fixation. AP radiographs were performed immediately postoperatively, 1 week, and 3 months. Bead migration was measured, and PROMs were compared. Results: Of 115 patients, 94 were available for final follow-up (82%). Average age was 52.1±10.5 years, and BMI was 30.8±5.4 kg/m2. There was no difference in tendon migration between OSPBT and ASPBT performed with an IS (P=0.70). OSPBT performed with one SSSA (21.70 mm) demonstrated significantly greater migration than ASPBT with IS (4.31mm, P&lt;0.001) and OSPBT with IS (5.04 mm, P&lt;0.001). Three patients (9.4%) who had OSPBT with one SSSA and one who had ASPBT with two SSSAs (3.8%), developed a Popeye deformity; none occurred in the IS groups. Mean 12-week bead migration in patients with versus without Popeye deformity was 60.8 mm and 11.2 mm, respectively (P&lt;0.0001). PROMs did not differ at final follow-up. Conclusions: ASPBT and OSPBT with IS fixation demonstrated the least tendon migration, while OSPBT with one SSSA yielded the most. Compared to IS, fixation with one, but not two, SSSAs resulted in significantly greater migration. Average bead migration following a Popeye deformity was 6.1cm. To minimize migration when using SSSAs, at least 2 sutures should be used with an interlocking pattern within the tendon. [Table: see text]

The Combined Suture Bridge With Mason-Allen Technique Is Superior to the Conventional Suture Bridge Technique for Arthroscopic Rotator Cuff Repair

To compare clinical results and retear rates between the combined suture bridge with Mason-Allen (SBMA) technique and the conventional suture bridge (SB) technique in patients with full-thickness rotator cuff tears who underwent arthroscopic rotator cuff repair. One hundred two patients who underwent arthroscopic rotator cuff repair using the SB technique (n= 50) or SBMA technique (n= 52) for a full-thickness rotator cuff tear and had at least 2years of follow-up were retrospectively analyzed. Magnetic resonance imaging was performed before surgery and 2 years after to determine preoperative tear size, Goutallier stage, and presence of retear after surgery. Patients were clinically evaluated using the Japanese Orthopaedic Association (JOA) score. The groups did not significantly differ in terms of follow-up period, age, sex, tear size, Goutallier stage, or number of suture anchors. The retear rate was significantly lower in the SBMA group (7.7% vs 28.0%; P < .01). The JOA score was significantly higher at last follow-up than before surgery in both groups (P <.01). The JOA score at last follow-up was significantly higher in the SBMA group (P= .02). Arthroscopic rotator cuff repair using the SBMA technique may provide better clinical and anatomical outcomes than the conventional SB technique. Level III, retrospective cohort design; treatment study).

Poster 294: Patellar Tendon Insertion is Not Distalized following Tibial Tubercle Osteotomy with Distalization

Objectives: Patella alta is a common anatomic risk factor in patients with patellofemoral instability and/or patellofemoral cartilage lesions, occurring in nearly 25% of these patients. Distalization tibial tubercle osteotomy (TTO) is effective in patients with patella alta in association with patellofemoral instability and cartilage lesions. Prior studies have suggested that increased patellar tendon length itself is a risk factor for recurrent patellofemoral instability, and have proposed the addition of a patellar tendon tenodesis via placement of a suture anchor proximal to the distalization TTO. However, concerns regarding increased patellofemoral cartilage stresses with addition of patellar tendon tenodesis have limited its adoption. The purpose of this study was to evaluate patellar tendon length and alignment parameters on preoperative and postoperative MRI and to evaluate patient reported outcomes (PROs) following distalization tibial tubercle osteotomy (TTO) without patellar tendon tenodesis in patients with patella alta. Methods: We conducted a retrospective review of 20 adult patients who underwent distalization TTO for patellar alta at our institution (December 2014-August 2021). All patients underwent preoperative and postoperative magnetic resonance (MR) imaging of the affected knee. Distalization TTO utilized a wedge-shaped osteotomy measuring ˜5cm in length and was fixed with two 4.5mm bicortical fully threaded screws following TT transfer. Caton-Deschamps (CDI), axial and sagittal TT-TG indices1, patellar tendon length and distances from tibial plateau to patellar tendon insertion and tibial tubercle were assessed (Figure 1). PROs included IKDC Subjective Knee Evaluation, KOOS Quality of Life Form, Kujala Anterior Knee Pain From, and Veterans RAND 12 Item Mental (VR12-MH) and Physical Health (VR12-PH) Surveys. Clinical data, including demographics, complication and perioperative data, was obtained from preoperative and postoperative charts in our electronic medical record. Results: Average age at time of surgery was 27.4 years (range: 14 – 42 years) and all patients were female. Average BMI was 24.9 +/- 4.4 kg/m2. Eleven patients (55%) were diagnosed with isolated patellofemoral cartilage lesions, four patients (20%) were diagnosed with patellofemoral instability without associated cartilage lesions and five patients (25%) were diagnosed with both instability and cartilage lesions. At the time of TTO distalization, eleven patients (55%) underwent matrix-induced autologous chondrocyte implantation (MACI), nine patients (45%) underwent MPFL reconstruction, four patients (20%) underwent lateral release/lengthening, and three patients (15%) underwent osteochondral allograft (OCA) implantation. Fourteen patients (70%) underwent anteromedialization of the tibial tubercle in addition to distalization. Radiographic parameters demonstrated improved patellar height (CDI decreased from 1.36 to 1.11 (p &lt; 0.001), improved rotational alignment (axial TT-TG decreased from 14.3mm to 11.1mm (p = 0.018)) and anteriorization of the TT (sagittal TT-TG increased from -4.3mm to -1.4mm (p = 0.037)) following distalization TTO. Distance from the tibial plateau to the PT insertion decreased from 20.1mm preoperatively to 17.9mm postoperatively (p&lt; 0.020) and patellar tendon length decreased from 53.4mm preoperatively to 50.0mm postoperative (p &lt; 0.001). Average distalization was 6.4mm. IKDC scores increased from 37.1 to 60.5 (p = 0.011), KOOS QOL scores increased from 19.5 to 42.1 (p &lt; 0.001), Kujala scores increased from 50.9 to 70.6 (p = 0.018), VR12-MH scores increased from 52.7 to 59.2 (p = 0.024) and VR12-PH scores increased from 35.1 to 41.7 (p = 0.009). Of the patients with preoperative patellofemoral instability, there were no cases of recurrent instability postoperatively. Ten patients (50%) underwent elective removal of hardware of TTO screws at an average of 10.7 months. There were four (20%) complications in this cohort, with two cases (10%) of postoperative arthrofibrosis requiring manipulation under anesthesia, one case (5%) of postoperative MRSA infection of the MPFL graft and one case (5%) of tibial tubercle delayed union requiring bone grafting and revision fixation. Conclusions: Distalization TTO without patellar tendon tenodesis is an effective surgical technique for improving patellar height in patients with patella alta and patellofemoral instability and/or patellofemoral cartilage lesions, with improvements in radiographic parameters and PROs postoperatively. There were no cases of recurrent instability in this cohort. The patellar tendon insertion does not appear to be significantly distalized following distalization TTO, likely related to scarring of the patellar tendon just proximal to the osteotomy site postoperatively. Given the complexity of risk factors associated with patellofemoral instability and patellofemoral cartilage lesions, distalization TTO provides an additional tool for patient-specific surgical management, without the need for patellar tendon tenodesis.