Outcomes of arthroscopic Bankart repair (ABR) for anterior shoulder instability using two knotless suture anchors fixation.

Objectives: The purpose of this study is to evaluate the short term outcomes of isolated Arthroscopic Bankart Repair (ABR) using knotless suture anchor technique, in young and middle aged patients with post traumatic Anterior Shoulder Instability (ASI). Study Design: Prospective Observational Study. Setting: Sports Units of Hayatabad Medical Complex, Peshawar. Period: January 2018 to December 2020. Material & Methods: 32 patients were included in this study, all of them were male, and who had traumatic anterior shoulder dislocation and underwent Arthroscopic Bankart Repair (ABR), with at least 2 years follow-up and minimum of 4 months of physiotherapy postoperatively. Sample size was calculated through non-probability consecutive sampling technique. Recurrent instability, postoperative glenohumeral osteoarthritis, post-surgical complications and subjective scores (Simple Shoulder Test [SST], American Shoulder and Elbow Surgeon [ASES] and Rowe scores) were evaluated. Results: Among the 32 participants, five patients (15.6%) experienced at least one episode of redislocation, eight patients (25%) had moderate to severe glenohumeral-osteoarthritis. The overall satisfaction rate was 76% with ASES, SST and Rowe scores of 82%, 9% and 79% respectively. One patient (3.12%) had wound infection. Conclusion: Isolated Arthroscopic Bankart Repair (ABR) using knotless suture anchor fixation for anterior shoulder instability followed by physiotherapy has excellent short term outcome in term of low post-surgical complication rate, high patient satisfaction, ability to joint work back and improved subjective scores, although high rate of postoperative glenohum eral osteoarthritis is disappointing necessitating further studies on the matter.

Arthroscopic Repair of Batter’s Shoulder

Background: Batter’s shoulder is a condition in which the posterior labrum is typically torn during the baseball swinging motion, producing a traumatic tear and posterior instability. The injury commonly occurs in the batter’s lead shoulder due to repetitive microtrauma, raising concern for switch-hitters due to the cumulative stress of throwing and swinging on the lead shoulder. Instability is commonly caused by a posterior humeral force and relative shoulder adduction, which is most prevalent during a swing attempt at a low and outside pitch. Indications: Damage to the labrum during the acute traumatic event can cause residual pain and recurrent instability of the shoulder. Indications include failed conservative management. The patient demonstrated a full-thickness longitudinal tear that was grossly unstable with gentle probing. Technique Description: After establishing presence of an unstable posterior labral tear during diagnostic arthroscopy, a 7-o’clock portal is established for the labral repair. A knotless suture anchor construct was utilized for its low-profile features. Care is taken to avoid both tangling of sutures and overtensioning of the repair. Results: Patients return to live batting practice at 6 months postoperatively and most patients return to the same level of play following surgical management. Discussion/Conclusion: Avoid overtightening of labral repair and subsequent loss of range of motion. Use of a low-profile knotless suture anchor is the senior author’s preferred method of surgical management. A majority of patients surgically managed for unstable posterior labral injuries return to the same level of play.

Knotless Suture Anchors: A Comparative Biomechanical Study of Acetabular Rim Anchor Fixation with Implications for Hip Labral Repair

The purpose of this study was to analyze relevant initial-implantation biomechanical properties of five knotless suture anchors available for use in acetabular labral repair. Five knotless suture anchor constructs were tested: Arthrex PushLock 2.9, Arthrex PushLock 2.4, Arthrex SutureTak 3.0, Stryker CinchLock SS 2.4, and Stryker CinchLock Flex 2.4. Anchors were placed in synthetic bone blocks and in acetabular bone of cadaveric specimens. Constructs were subjected to cyclic and load-to-failure (LTF) testing. Displacement at 1, 100, 250, and 500 cycles, yield load, ultimate load, and failure mode were compared with statistically significant (p < 0.005) differences. PushLock 2.9 mm and CinchLock SS 2.4 anchor constructs had significantly less displacement than PushLock 2.4 mm after 1 cycle (p = 0.017) and 500 cycles (p = 0.043). Excluding “tare” displacement after the first cycle, all anchor constructs were associated with less than 2.0 mm of displacement after 500 cycles. Arthrex PushLock 2.4 and SutureTak 3.0 had the highest number of failures prior to completing cyclic loading. Arthrex PushLock 2.9 was associated with the highest LTF in cadaver (p = 0.00013) and synthetic (p = 0.009) bone models. Most common failure mode in cadaver bone was eyelet failure for all anchor types. Knotless suture anchors used for arthroscopic hip surgery (2.9 mm PushLock, 2.4 mm PushLock, 3.0 mm SutureTak, 2.4 mm CinchLock SS, and 2.4 mm CinchLock Flex) were associated with material properties that met or exceeded the reported thresholds for successful periarticular soft tissue repair surgeries. Based on cyclic and LTF testing in synthetic bone blocks and cadaveric acetabulums, 2.9 mm PushLocks and 2.4 mm CinchLock SS anchors may have potential biomechanical advantages over the other constructs tested. Further functional ex vivo and preclinical animal model studies are recommended to further characterize suture anchor constructs designed for acetabular labrum repair. These results provide novel and relevant biomechanical testing data that contribute to assessing knotless suture anchor constructs for use in acetabular labral repair.

Self-Tensioning Feature of Knotless Suture Anchor Provides Reproducible Knotless Fixation Independent of Initial Tension

Background: Anterior cruciate ligament (ACL) reconstruction with suture tape reinforcement has been shown to biomechanically reduce elongation and increase ultimate strength. However, the amount and consistency of the achieved tension after primary fixation using knotless suture anchors remains unclear. Purpose: To determine whether initial tensioning of suture tape before fixation with a knotless suture anchor significantly affects final tension of the suture tape. Study Design: Controlled laboratory study. Methods: We secured 15 pairs of Sawbones blocks with predrilled tunnels to a tensile testing machine. Suture tape was inserted through a suspensory fixation button on the representative femoral block and threaded top-down through the base of the tibial block over an attachable button system. The suture tape was attached with a knotless suture anchor in a predrilled and tapped hole on the tibial block under the following pretensioning conditions: (1) slight tension of 5 N, (2) no tension, and (3) initial slack. The suture anchor was inserted as the load-time data were recorded. After initial block testing, a porcine model of 24 tibias was used to test the same pretensioning conditions. The initial loads during anchor insertion and screw-in were measured, as well as final tension. Results: During block testing, no difference in final tensioning was found when comparing the slight-tension, no-tension, and slack groups (42.3 ± 5.3, 37.7 ± 6.4, and 40.2 ± 7.0 N, respectively; P = .528). Similar to block testing, no difference in final tensioning was found when comparing the slight-tension, no-tension, and slack groups using the porcine model (43.64 ± 6.69, 48.09 ± 13.93, and 44.52 ± 6.84 N, respectively; P = .633). Conclusion: The final tension of the suture tape construct appears to be reproducible and consistent, independent of the initial tension introduced with suture anchor placement within the tested parameters. Clinical Relevance: The results of the current study can help optimize the placement technique of independent suture tape reinforcement for ACL reconstruction, which is a promising strategy to help prevent ACL rerupture, particularly in the early phases of postoperative rehabilitation.

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.

Biomechanical Analysis of Patellar Tendon Repair With Knotless Suture Anchor Tape Versus Transosseous Suture

Background: Patellar tendon ruptures have routinely been repaired with transosseous suture tunnels. The use of knotless suture anchors for repair has been suggested as an alternative. Purpose: To compare the load to failure and gap formation of patellar tendon repair at the inferior pole of the patella with knotless suture anchor tape versus transosseous sutures. A secondary objective was to investigate whether either technique shows an association between bone density and load to failure. Study Design: Controlled laboratory study. Methods: A total of 20 human tibias with attached patellar and quadriceps tendons were sharply incised at the bone-tendon junction at the inferior pole of the patella. A total of 10 tendons were repaired using 2 knotless suture anchors in the inferior pole of the patella and a single suture tape with 2 core sutures. The other 10 tendons were repaired using No. 2 suture passed through 3 transosseous tunnels. A distracting force was then applied through the suture in the quadriceps tendon. Gap distance through load cycling at the repair site and maximum load at repair failure were then measured. Bone density was measured using computed tomography scanning. Results: No difference was found in the mean load to failure of knotless patellar tendon repair versus transosseous suture repair (367.6 ± 112.2 vs 433.9 ± 99 N, respectively; P = .12). After 250 cycles, the mean repair site gap distance was 0.85 ± 0.45 mm for the knotless patellar tendon repair versus 2.94 ± 2.03 mm for the transosseous suture repair ( P = .03). A small correlation, although not statistically significant, was found between bone density and load to failure for the knotless tape repair ( R 2 = 0.228; P = .66). No correlation was found between bone density and load to failure for the transosseous repair ( R 2 = 0.086; P = .83). Conclusion: Suture tape repair with knotless anchors for repair of patellar tendon rupture has comparable load to failure with less gap formation than transosseous suture repair. There is a small correlation between bone density and failure load for knotless anchor repair, which may benefit from further investigation. Clinical Relevance: Using knotless suture anchors for patellar tendon rupture repair would allow for a smaller incision, less dissection, and likely shorter operating time.