The use of anchors in shoulder surgery: a shift from metallic to bioabsorbable anchors

Magnetic resonance imaging for relationship between the severity of perianchor fluid collection and rotator cuff integrity after arthroscopic double-row suture-bridge rotator cuff repair

PURPOSE

The primary purpose of this study was to assess perianchor fluid collection (PFC) severity of medial anchor and rotator cuff integrity association after arthroscopic double-row suture-bridge rotator cuff repair (RCR) and the secondary purpose was to identify the demographic and radiologic risk factors for high-grade PFC.

HYPOTHESIS

Re-tear rate would be significant higher in patients with high-grade PFC.

METHODS

We retrospectively reviewed patients with arthroscopic double-row suture-bridge RCR for full-thickness rotator cuff tear (RCT) at our institution between February 2012 and May 2018. Based on the PFC severity, they were divided into the no-fluid (no fluid collection), low-grade (minimal or local fluid collection around the anchor), and high-grade (fluid collection beyond the entire length of the anchor) groups. Magnetic resonance imaging was performed 6 months postoperatively for assessing PFC severity and repaired rotator cuff integrity association, besides evaluating correlation between severity and various demographic and radiologic factors, including work level (low/medium/high) and RCT size.

RESULTS

This study included 312 patients, 181 (58%) in the no fluid group, 82 (26.3%) in the low-grade PFC group, and 49 (15.7%) in the high-grade PFC group. Re-tear occurred in 73 (23.4%) patients and was more frequent in the high-grade group (26/49 [53.1%]) than in the no-fluid (27/181 [14.9%]; p<0.001) and low-grade (20/82 [24.4%]; p=0.001) groups, without statistically significant differences between the latter two (p=0.082). Among the demographic factors, work level (low/medium/high) differed significantly between the no-fluid (22.1%/58.0%/19.9%), low-grade (25.7%/46.3%/28.0%), and high-grade (26.5%/34.7%/38.8%) groups (p=0.026). Among the radiologic factors, the mediolateral tear size differed significantly between the three groups (no-fluid group: 1.7±0.8cm, low-grade group: 1.8±0.6cm, high-grade group: 2.2±1.0cm; p=0.003). Multivariate regression analysis showed that mediolateral tear size (odds ratio: 1.821; 95% confidence interval: 1.258-2.636; p=0.001) was an independent risk factor for high-grade PFC.

CONCLUSIONS

After arthroscopic double-row suture-bridge RCR, the highest re-tear rate was observed in patients with high-grade PFC, while there was no significant difference in rates between no-fluid and low-grade PFC groups. As PFC severity increased, the risk of re-tear increased. In particular, larger mediolateral tear size was associated with high-grade PFC.

LEVEL OF EVIDENCE

III; case-control study.

Safety and efficacy of second-generation all-suture anchors in labral tear arthroscopic repairs: prospective, multicenter, 1-year follow-up study

Background

This study's primary aim was to assess the safety and performance of second-generation all-soft suture anchors following arthroscopic labral tear repair.

Methods

This prospective, multicenter study was conducted by 6 surgeons at 6 sites in Europe and the United States between November 2018 and August 2020. Patients who required shoulder arthroscopic repair, for a range of labral injuries, were treated with a second-generation all-soft suture anchor. The primary outcome was clinical success rate (percentage of patients without signs of failure and/or reintervention) at 6 months. Secondary outcomes included clinical success rate at 12 months, intraoperative anchor deployment success rate, and patient-reported outcomes (PROs) at 6 and 12 months, including visual analog scale (VAS) pain assessment, VAS satisfaction assessment, EQ-5D-5L Index Score, EQ-5D-5L VAS Health Score, Rowe Shoulder Score for Instability, American Shoulder and Elbow Surgeons score, and Constant-Murley Shoulder Score. Serious adverse events and serious adverse device effects were collected throughout the study.

Results

Forty-one patients were enrolled (mean age, 28.2 years; 87.8% male, 12.2% female). Clinical success was achieved in 27/28 and 31/32 patients at 6 months and 12 months, respectively. Anchor deployment had a 100% success rate. Significant improvements over baseline were reported for all PROs except Constant-Murley Shoulder (6 months) and VAS Satisfaction Score (12 months). One patient experienced 1 serious adverse event and 1 patient experienced 1 serious adverse device effect.

Conclusion

Second-generation all-soft suture anchors used in this study demonstrated a high clinical success rate, a favorable safety profile, and patients exhibited significant improvement in PROs.

Minimum 10-year follow-up outcomes of arthroscopic Bankart's repair with metallic anchors: Reliable results with low redislocation rates

BACKGROUND

With stiff competition from alternative albeit more expensive counterparts, it has become important to establish the applicability of metallic anchors for shoulder instability in the modern era. This can be accomplished, in part, by analysing long-term outcomes.

AIM

To analyse minimum 10-year outcomes from 30 patients following arthroscopic anterior stabilisation using metallic anchors.

METHODS

Prospectively collected data from arthroscopic Bankart repairs performed using metal anchors during 2007P-2010 were retrospectively analysed in this single-surgeon study. Comprehensive data collection included historical and clinical findings, dislocation details, operative specifics, and follow-up radiological and clinical findings including shoulder scores. The primary outcomes were patient-reported scores (Constant, American Shoulder and Elbow Surgeons [ASES], and Rowe scores) and pain and instability on a visual analogue scale (VAS).

RESULTS

A 3% recurrence rate of dislocation was noted at the final follow-up. Total constant scores at 10 years postoperatively measured between 76 and 100 (mean 89) were significantly better than preoperative scores (mean 62.7). Congruous improvements were also noted in the Rowe and ASES scores and VAS at the 10-year review.

CONCLUSION

Reliable long-term outcomes with metallic anchors in surgery for shoulder instability can be expected. Our results provide additional evidence of their continued, cost-effective presence in the modern scenario.

Retrospective Comparative Analysis of Clinical and Functional Outcome After Arthroscopic Bankart Repair using All-Suture Anchor and Metal Anchor

Introduction

Both knotted all suture anchors and metal anchors are used for arthroscopic Bankart repair. We retrospectively evaluated and compared clinical and functional outcomes after arthroscopic Bankart repair using the knotted all-suture anchors and knotted metal anchors.

Materials and methods

In a retrospective cohort analysis, patients who underwent arthroscopic Bankart repair without any concomitant additional lesion repair using either all-suture anchors or metal anchors, between January 2015 and May 2018 were identified. Their pre- and post-operative functional and clinical outcomes were compared using Rowe and WOSI scores. The recurrence rate in the two groups was also compared.

Results

A total of 41 patients in all suture anchors group and 47 in the metal anchors group were identified as per inclusion and exclusion criteria. The demographic profile of both groups was comparable. There was no significant difference in clinical and functional outcome between the two suture anchor groups as per Rowe (pre-operative 40.13+6.51 vs 38.09+6.24 and post-operative 2 years 93.28+7.09 vs 92.55+9.2) and WOSI (pre-operative 943.05+216.64 vs 977.55+165.46 and post-operative 2 years 278.21+227.56 vs 270.94+186.25) scores. There was a significant improvement in both the groups between preoperative and post-operative ROWE and WOSI scores at 6 months and 2 years follow-up as compared to pre-operative scores (p<0.001). Re-dislocation rates were also comparable (4.8% vs 6.3%).

Conclusion

All-suture anchors showed comparable clinical and functional results as the metal anchors for arthroscopic Bankart repair at two-year follow-up.

Osteolysis Following the Use of Polyetheretherketone Suture Anchors in Hand and Wrist Surgery: A Preliminary Study

PURPOSE

The objective of this study was to investigate and describe the presence of osteolysis after implantation of polyetheretherketone (PEEK) suture anchors in the hand and wrist.

METHODS

Patients who underwent hand or wrist surgery using PEEK suture anchor(s) at a large academic institution from January 2019 to January 2021 were identified. Patients without accessible intraoperative fluoroscopic imaging were excluded. Patient demographics, type of procedure, and suture anchor material were recorded. The suture anchor tunnel size was measured on sequential radiographs and recorded as percentage change. Descriptive statistics were used to summarize findings.

RESULTS

A total of 26 PEEK suture anchors in 14 patients were included, with an average follow-up of 12.0 months (range, 1.5-24.1 months). Twenty-seven percent of the anchors (7/26) demonstrated osteolysis at final follow-up, as defined by enlargement of tunnel size by >30%. In all anchors, the tunnel size increased by 19.1% on average (range, -7.7% to 56.1%) by final follow-up.

CONCLUSIONS

Polyetheretherketone suture anchors may be associated with the development of osteolysis in hand and wrist surgery. The clinical implications of osteolysis in the smaller bones of the hand and wrist remain unclear.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Polyetheretherketone development in bone tissue engineering and orthopedic surgery

Polyetheretherketone (PEEK) has been widely used in the medical field as an implant material, especially in bone tissue engineering and orthopedic surgery, in recent years. This material exhibits superior stability at high temperatures and is biosecured without harmful reactions. However, the chemical and biological inertness of PEEK still limits its applications. Recently, many approaches have been applied to improve its performance, including the modulation of physical morphology, chemical composition and antimicrobial agents, which advanced the osteointegration as well as antibacterial properties of PEEK materials. Based on the evolution of PEEK biomedical devices, many studies on the use of PEEK implants in spine surgery, joint surgery and trauma repair have been performed in the past few years, in most of which PEEK implants show better outcomes than traditional metal implants. This paper summarizes recent studies on the modification and application of biomedical PEEK materials, which provides further research directions for PEEK implants.

Biomechanical comparison of different suture anchors used in rotator cuff repair surgery-all-suture anchors are equivalent to other suture anchors: a systematic review and network meta-analysis

PURPOSE

Suture anchors are commonly used to repair rotator cuff tendons in arthroscopy surgery, and several anchor materials have been created to maximize pull-out strength and minimize iatrogenic damage. We hypothesized that all-suture anchors have biomechanical properties equivalent to those of conventional anchors. Our purpose is to compare the biomechanical properties of different anchors used for rotator cuff repair.

METHODS

The Embase, PubMed, Cochrane, and Scopus databases were searched for biomechanical studies on various suture anchors. The search keywords included rotator cuff tears and suture anchors, and two authors conducted study a selection, risk of bias assessment, and data extraction. The failure load, stiffness, and displacement were calculated using the mean differences with 95% confidence intervals (CIs). Failure modes were estimated using summary odds ratios with 95% CIs. The surface under the cumulative ranking curve was used for the relative ranking probabilities. A sensitivity analysis was performed by excluding studies using synthetic bones.

RESULTS

The polyetheretherketone (PEEK) (p < 0.001) and all-suture anchors (p < 0.001) had higher failure loads than the biocomposite anchors, whereas no significant difference was observed in stiffness among the anchors. The all-suture (p = 0.006) and biocomposite anchors (p < 0.001) had displacements higher than the metal anchors. The relative ranking of the included anchors in failure loads and displacement changed in sensitivity analysis. The meta-analysis did not find significant differences, but the relative ranking probabilities suggested that all-suture anchor had a higher rate of anchor pull-out and a lower rate of eyelet or suture breakage. In contrast, the metal anchors were associated with a higher number of eyelet breakage episodes.

CONCLUSIONS

All-suture anchors showed significantly higher failure loads than the biocomposite anchors and similar cyclic displacements to the biocomposite and PEEK anchors. There were no significant differences in stiffness between all-suture and conventional suture anchors. The relative ranking of biomechanical properties changed in sensitivity analysis, suggesting the potential effect of bone marrow density.

LEVEL OF EVIDENCE

Level IV.

Mini All-Suture Anchors for Repairing the Central Slip of the Extensor Tendon at the Proximal Interphalangeal Joint: A Biomechanical Investigation

PURPOSE

This study evaluated 1.0-mm mini suture anchors for repairing the central slip of the extensor mechanism at the proximal interphalangeal joint. Studies have reported a requirement for central slip fixation to withstand 15 N during postoperative rehabilitation exercises and 59 N during forceful contraction.

METHODS

Index and middle fingers from 10 matched pairs of cadaveric hands were prepared with 1.0-mm mini suture anchors with 2-0 sutures or threaded with 2-0 sutures through a bone tunnel (BTP). In total, 10 index fingers from unmatched hands were prepared with suture anchors and fixed to the extensor tendons to evaluate the tendon/suture interface response. Each distal phalanx was secured to a servohydraulic testing machine, and ramped tensile loads were applied to suture or tendon until failure.

RESULTS

All anchors for the all-suture bone tests failed because of pullout from the bone (Mean failure force = 52.5+/-17.3 N). Three anchors from the tendon-suture pull out test failed by pullout from the bone and seven failed at the tendon/suture interface (Mean failure force = 49.0+/-10.1 N).

CONCLUSIONS

The 1.0-mm mini suture anchor provides enough strength for early short-arc motion, but it may not be adequate for forceful contraction in the early postoperative rehabilitation stage.

CLINICAL RELEVANCE

The site of fixation, the type of anchor, and the type of suture used are key factors to consider for early range of motion, after surgery.

Clinical perspectives for repairing rotator cuff injuries with multi-tissue regenerative approaches

Background

In the musculoskeletal system, bone, tendon, and muscle form highly integrated multi-tissue units such as the rotator cuff complex, which facilitates functional and dynamic movement of the shoulder joint. Understanding the intricate interplay among these tissues within clinical, biological, and engineering contexts is vital for addressing challenging issues in treatment of musculoskeletal disorders and injuries.

Methods

A wide-ranging literature search was performed, and findings related to the socioeconomic impact of rotator cuff tears, the structure-function relationship of rotator cuff bone-tendon-muscle units, pathophysiology of injury, current clinical treatments, recent state-of-the-art advances (stem cells, growth factors, and exosomes) as well as their regulatory approval, and future strategies aimed at engineering bone-tendon-muscle musculoskeletal units are outlined.

Results

Rotator cuff injuries are a significant socioeconomic burden on numerous healthcare systems that may be addressed by treating the rotator cuff as a single complex, given its highly integrated structure-function relationship as well as degenerative pathophysiology and limited healing in bone-tendon-muscle musculoskeletal tissues. Current clinical practices for treating rotator cuff injuries, including the use of commercially available devices and evolving trends in surgical management have benefited patients while advances in application of stem/progenitor cells, growth factors, and exosomes hold clinical potential. However, such efforts do not emphasize targeted regeneration of bone-tendon-muscle units. Strategies aimed at regenerating bone-tendon-muscle units are thus expected to address challenging issues in rotator cuff repair.

Conclusions

The rotator cuff is a highly integrated complex of bone-tendon-muscle units that when injured, has severe consequences for patients and healthcare systems. State-of-the-art clinical treatment as well as recent advances have resulted in improved patient outcome and may be further enhanced by engineering bone-tendon-muscle multi-tissue grafts as a potential strategy for rotator cuff injuries.

Translational Potential of this Article

This review aims to bridge clinical, tissue engineering, and biological aspects of rotator cuff repair and propose a novel therapeutic strategy by targeted regeneration of multi-tissue units. The presentation of these wide-ranging and multi-disciplinary concepts are broadly applicable to regenerative medicine applications for musculoskeletal and non-musculoskeletal tissues.

Biomechanical properties of a suture anchor system from human allogenic mineralized cortical bone matrix for rotator cuff repair

Background

Suture anchors (SAs) made of human allogenic mineralized cortical bone matrix are among the newest developments in orthopaedic and trauma surgery. Biomechanical properties of an allogenic mineralized suture anchor (AMSA) are not investigated until now. The primary objective was the biomechanical investigation of AMSA and comparing it to a metallic suture anchor (MSA) and a bioabsorbable suture anchor (BSA) placed at the greater tuberosity of the humeral head of cadaver humeri. Additionally, we assessed the biomechanical properties of the SAs with bone microarchitecture parameters.

Methods

First, bone microarchitecture of 12 fresh frozen human cadaver humeri from six donors was analyzed by high-resolution peripheral quantitative computed tomography. In total, 18 AMSAs, 9 MSAs, and 9 BSAs were implanted at a 60° angle. All three SA systems were systematically implanted alternating in three positions within the greater tuberosity (position 1: anterior, position 2: central, position 3: posterior) with a distance of 15 mm to each other. Biomechanical load to failure was measured in a uniaxial direction at 135°.

Results

Mean age of all specimens was 53.6 ± 9.1 years. For all bone microarchitecture measurements, linear regression slope estimates were negative which implies decreasing values with increasing age of specimens. Positioning of all three SA systems at the greater tuberosity was equally distributed (p = 0.827). Mean load to failure rates were higher for AMSA compared to MSA and BSA without reaching statistical significance between the groups (p = 0.427). Anchor displacement was comparable for all three SA systems, while there were significant differences regarding failure mode between all three SA systems (p < 0.001). Maximum load to failure was reached in all cases for AMSA, in 44.4% for MSA, and in 55.6% for BSA. Suture tear was observed in 55.6% for MSA and in 22.2% for BSA. Anchor breakage was solely seen for BSA (22.2%). No correlations were observed between bone microarchitecture parameters and load to failure rates of all three suture anchor systems.

Conclusions

The AMSA showed promising biomechanical properties for initial fixation strength for RCR. Since reduced BMD is an important issue for patients with chronic rotator cuff lesions, the AMSA is an interesting alternative to MSA and BSA. Also, the AMSA could improve healing of the enthesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05371-0.

Does the immediate repair of Bankart lesion following first dislocation reduce the chances of recurrence after arthroscopic repair in soldiers?

PURPOSE

The study attempted to compare the effects of immediate and delayed arthroscopic Bankart repair on the shoulder dislocation recurrence.

METHODS

In total, 465 soldiers with first-time anterior shoulder dislocation were included in the study. Of the total, 285 soldiers underwent a quick arthroscopic Bankart repair procedure, whether 180 soldiers underwent a delayed repair procedure. The initial dislocation was traumatic in both groups and operated using the standard arthroscopic suture anchor repair technique. Patient's age, repair time since the first dislocation, number of dislocations before surgery, number of suture anchors used during the repair, duration of surgical procedure, duration from surgery to return to work, and recurrence of dislocation after surgery were recorded. Rowe score, Constant score, and American Shoulder and Elbow Surgeons score were used for clinical assessment.

RESULTS

The operating time and recurrence rate were higher in the group subjected to delayed repair procedure than in the group subjected to immediate repair procedure. Repair timing was found to be crucial for a successful outcome.

CONCLUSIONS

The findings suggest that Bankart repair must be performed immediately to minimize recurrence and other degenerative changes, which may require an additional surgical procedure for satisfactory repair. More studies are required to reach a definitive conclusion.

LEVELS OF EVIDENCE

Level III.

Biomaterials Used for Suture Anchors in Orthopedic Surgery

Suture anchors are broadly used for attaching soft tissue (e.g., tendons, ligaments, and meniscus) to the bone and have become essential devices in sports medicine and during arthroscopic surgery. As the usage of suture anchors has increased, various material-specific advantages and challenges have been reported. As a result, suture anchors are continually changing to become safer and more efficient. In this ever-changing environment, it is clinically essential for the surgeon to understand the key characteristics of existing anchors sufficiently. This paper aims to summarize the current concepts on the characteristics of available suture anchors.

Single-Portal, Single-Anchor Repair of a Superior Third Subscapularis Tear Using a Self-Punching Knotless Soft Suture Anchor

Numerous techniques exist for arthroscopic subscapularis repair with varying degrees of complexity based on tear morphology, all of which have established satisfactory outcomes in function and patient satisfaction. Arthroscopic subscapularis repair can require several working portals and suture anchors, increasing both technical complexity and operative time. This Technical Note describes an arthroscopic repair of a superior one-third subscapularis tear using a self-punching knotless soft suture anchor through a single anterior working portal. Thus, we offer a unique approach to arthroscopic repair of superior one-third subscapularis tears that is time-saving, reproducible, and highly efficient while minimizing iatrogenic damage and postoperative complications.

Arthroscopic Bankart revision using all suture anchor in recurrent anterior shoulder dislocation: A case report

•

All suture anchor has the same biomechanical strength as conventional metallic anchor.

•

Recurrent shoulder dislocation after arthroscopic Bankart repair is still a problem.

•

The all suture anchor technique offers benefit of bone preservation and strong fixation.

Introduction

Arthroscopic Bankart revision after recurrent shoulder dislocation is still a matter of discussion. Several factors are contributing to this injury. Recently the development of all suture anchors has grown in popularity in arthroscopic stabilization. It was proven to preserve bone stock, smaller in size thus more anchors can be made.

Presentation of case

We presented a case of 27-year-old woman with recurrent anterior dislocation after seven years of arthroscopic Bankart repair. Seven years before, we performed Bankart repair using three 2.8 mm fiber-wire anchor (FASTak® (Arthrex, Karsfield Germany)). For the revision surgery we performed arthroscopic revision using four all suture anchor technique (Y-Knot® Flex All-Suture Anchor, 1.3 mm – One strand of #2 Hi-Fi® (Conmed, New York)).

Discussion

From preoperative and intraoperative assessment, we found no anchor failure and no massive bony lesion. To preserve the bone stock we insert four all suture anchors between the old anchor. One year post-operative follow up showed that patient could gain normal range of movement. No early or late complications were observed.

Conclusion

Compared to the conventional metallic anchor, all suture anchor has the same biomechanical strength. Moreover due to its relatively small size, it can reserve bone stock and more anchors can be made thus adding more stability to the shoulder.

All-suture anchors versus metal suture anchors in the arthroscopic treatment of traumatic anterior shoulder instability: A comparison of mid-term outcomes

OBJECTIVES

This study aims to compare metal suture anchors and all-suture anchors clinically and radiologically in arthroscopic Bankart repair.

PATIENTS AND METHODS

In this retrospective study, 67 patients (61 males, 6 females; mean age 26.0±5.8; range, 18 to 43 years) who underwent arthroscopic Bankart repair between April 2009 and October 2016 were divided into two groups depending on the type of the suture anchor used in different periods. Group A comprised 32 patients with arthroscopic Bankart repair performed with metal suture anchors, and Group B comprised 35 patients with arthroscopic Bankart repair performed with all-suture anchors. The patients were clinically evaluated using Rowe scores, Constant scores, redislocation rates, and positive apprehension test rates. Radiographic evaluation was performed using the Samilson-Prieto classification to observe the development of glenohumeral osteoarthritis.

RESULTS

The mean follow-up period was 41.1±10.4 (range, 30 to 60) months in Group A, and 39.6±9.4 (range, 28 to 60) months in Group B, with no significant difference between the two groups (p=0.559). No significant difference was observed between Group A and Group B in terms of mean Rowe score (89.2±13.8 [range, 40 to 100] vs. 88.7±16.9 [range, 25 to 100]; p=0.895) or Constant score (87.2±8.9 [range, 48 to 96] vs. 86.9±9.0 [range, 46 to 96]; p=0.878), which were the clinical outcomes at the final follow-up examination. Postoperative redislocation rates (3.1% vs. 2.9%, p=1.0) and positive apprehension test rates (6.3% vs. 8.6%, p=1.0) were found to be similar in both groups. According to the Samilson-Prieto classification, there was no evidence of glenohumeral osteoarthritis in any of the patients in either group.

CONCLUSION

Satisfactory outcomes were obtained with the use of all-suture anchors in arthroscopic Bankart repair for traumatic anterior shoulder instability. All-suture anchors and metal suture anchors, have similar outcomes in the mid-term and all-suture anchors are a reliable and effective option for arthroscopic Bankart repair.

Comparison of Outcome of Deltoid Ligament Repair According to Location of Suture Anchors in Rotational Ankle Fracture

BACKGROUND

The suture anchors for the repair of deltoid ligament in rotational ankle fracture are inserted mostly into the medial malleolus, but sometimes are placed into the talus depending on the rupture site. This study sought to compare the radiological and clinical outcomes of deltoid ligament repair according to using these 2 locations for suture anchor placement.

METHODS

The cases of 131 patients (114 patients with suture anchors on the medial malleolus and 17 patients with suture anchors on the talus) who underwent deltoid ligament repair along with ankle fracture fixation were retrospectively reviewed. Medial clear space oblique (MCSo), medial clear space perpendicular (MCSp), tibiofibular clear space (TFCS), and tibiofibular overlap (TFO) were measured as radiological outcomes, while the Olerud-Molander Ankle Score (OMAS) and visual analog scale (VAS) score for pain were calculated as clinical outcomes. The follow-up period did not differ between the 2 groups (16.8 ± 10.9 months in the medial malleolus group vs 17.9 ± 14.3 months in the talus group; P = .670).

RESULTS

There were no differences in MCSo, MCSp, TFCS, and TFO at 3 months after surgery and final follow-up. The OMAS and VAS for pain did not show intergroup differences at final follow-up.

CONCLUSION

The surgical outcome of deltoid ligament repair in rotational ankle fracture did not differ whether the suture anchors were inserted into the medial malleolus or into the talus.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

A Comparison of Open-Construct PEEK Suture Anchor and Non-Vented Biocomposite Suture Anchor in Arthroscopic Rotator Cuff Repair: A Prospective Randomized Clinical Trial

PURPOSE

To compare radiologic bone ingrowth and the clinical outcomes of an open-construct (PEEK) (polyether ether ketone) suture anchor with those of a non-vented biocomposite suture anchor in patients with arthroscopic rotator cuff repair.

METHODS

Sixty-nine patients were randomly allocated into 2 groups based on type of suture anchors used for rotator cuff repair; group 1: open-construct PEEK anchor (36 patients), group 2: non-vented biocomposite anchor (33 patients). The status of bone ingrowth into the anchor and the presence of cyst formation were evaluated at 6 months postoperatively by computed tomography scan using the Modified Barber's ossification scale. The American Shoulder and Elbow Surgeons score, Constant score, and visual analog scale score for pain and range of motion were evaluated. Magnetic resonance imaging or ultrasonography was performed at 12 months postoperatively to examine the integrity of the repaired rotator cuff tendon.

RESULTS

Significant improvements in shoulder function and pain relief were observed regardless of the anchor used (both Group 1 and 2; P < .001). No differences were found in functional scores and range of motion between the 2 groups. Group 1 showed better bone ingrowth grades than group 2 (poor 2.8 vs 24.2%, fair 27.8 vs 39.4%, good 38.9 vs 33.3%, and excellent 30.6 vs 3.0%; P < .001). The rate of cyst formation around the anchor on the 6 months' postoperative computed tomography (group 1: 14% and group 2: 12%) and re-tear rate at 12 months (5% each) showed no difference between the 2 groups.

CONCLUSIONS

Shoulder function was improved after complete rotator cuff repair and similar clinical outcomes were achieved regardless of suture anchor material and shape. However, the open-construct PEEK anchor provided better bone ingrowth into the anchor than the non-vented biocomposite anchor at 6 months after arthroscopic rotator cuff repair.

LEVEL OF EVIDENCE

Level I; Prospective Randomized Trial.

Long-term Follow-up of Extensive Peri-anchor (Poly-L/D-lactic Acid) Cyst Formation after Arthroscopic Rotator Cuff Repair: A Case Report

Suture anchors are commonly used in shoulder surgeries, especially for rotator cuff tears. Peri-anchor cyst formation, however, is sometimes detected on follow-up radiologic image after surgery. The purpose of this report is to discuss the case of a patient who presented with regression of extensive peri-anchor cyst on postoperative 4-year follow-up magnetic resonance imaging and had good clinical outcome despite peri-anchor cyst formation after arthroscopic rotator cuff repair.

Fixation methods and implants in shoulder stabilization: A historical perspective

BACKGROUND

Treatment for shoulder instability has changed significantly over the past decade from open procedures to arthroscopic procedures using a variety of different fixation methods and implants. The development of these implants has been highly influenced by the numerous complications that have arisen using early designs.

METHODS

A review of the literature was performed to describe the history of shoulder stabilization.

CONCLUSION

As biomedical technology improves, we should continue to see changes to implant design and manufacturing. Having an understanding of the history and evolution of these implants will provide us with context in which to guide future implant design and clinical use. This review article provides a comprehensive overview of the evolution of early shoulder stabilization techniques and implants to the modern implants being used today.

Analysis of glenoid inter-anchor distance with an all-suture anchor system

Background

All-suture anchors used in arthroscopic shoulder stabilization employ small diameter anchors, which allow greater placement density on narrow surfaces such as the glenoid. There is no consensus in the literature about how close to one another two anchors may be implanted.

Purpose

The purpose of the present study is to compare the strength characteristics of two all-suture anchors placed in cadaveric human glenoid at variable distances to one another, in order to determine the minimum distance required for optimal strength.

Methods

Twelve fresh-frozen human cadaveric glenoids were implanted with 1.4 mm all-suture anchors at varying inter-anchor distances. Each glenoid was used for four tests, for a total of 48 tests. Anchors were implanted adjacent to one another or with 2, 3, or 5 mm bone bridges between pilot holes. The glenoids then underwent pullout testing using a test frame with a 5N preload followed by displacement of 12.5 mm/s. The primary outcomes were stiffness, failure strength, and ultimate strength.

Results

Stiffness was 13.52 ± 3.8, 17.97 ± 5.02, 17.59 ± 4.65 and 18.95 ± 4.67 N/mm for the adjacent, 2, 3, and 5 mm treatment groups, respectively. The adjacent group had a significantly lower stiffness compared to the other treatment groups. Failure strength was 48.68 ± 20.64, 76.16 ± 23.78, 73.19 ± 35.83 and 87.04 ± 34.67 N for the adjacent, 2, 3, and 5 mm treatment groups, respectively. The adjacent group had a significantly lower failure strength compared to the other treatment groups. Ultimate strength was also measured to be 190.59 ± 140.93, 268.7 ± 115.1, 283.23 ± 118.43, and 291.28 ± 118.24 for the adjacent, 2, 3, and 5 mm treatment groups, respectively.

Conclusions

This biomechanical study provides evidence that 1.4 mm all-suture anchors demonstrate similar strength characteristics when placed at least 2 mm or greater from one another. When 1.4 mm all-suture anchors were placed adjacent to one another, there was an observed decrease in failure strength and stiffness.

Clinical relevance

This study suggests that 1.4 mm all-suture anchors may be placed as close as 2 mm to one another while preserving strength characteristics.

Arthroscopic Repair of Type II SLAP Tears Using Suture Anchor Technique

Arthroscopic SLAP tear repair has become an increasingly used treatment for patients presenting with symptomatic SLAP tears after failed nonoperative management. Debridement, SLAP repair, and open or arthroscopic biceps tenodesis or tenotomy have been used for the treatment of SLAP tears. Various techniques for repair have been described, and furthermore, there is a high incidence of concomitant pathology of the shoulder. Repair remains an excellent option in isolated SLAP tears amenable to repair, with excellent outcomes in well-indicated patients. We present a method for repairing a SLAP tear using standard suture anchor fixation, anterior and posterior portals, and an accessory portal of Wilmington. Adequate labral repair can be achieved with this technique in patients with no concomitant biceps pathology. This report highlights this technique for SLAP repair in patients with isolated symptomatic SLAP tears that have failed conservative management.

Biomechanical Comparison of a First- and a Second-Generation All-Soft Suture Glenoid Anchor

Background:

All–soft tissue suture anchors provide advantages of decreased removal of bone and decreased glenoid volume occupied compared with traditional tap or screw-in suture anchors. Previous published data have led to biomechanical concerns with the use of first-generation all-soft suture anchors.

Purpose/Hypothesis:

The purpose of this study was to evaluate the load to 2-mm displacement and ultimate load to failure of a second-generation all-soft suture anchor, compared with a first-generation anchor and a traditional PEEK (polyether ether ketone) anchor. The null hypothesis was that the newer second-generation anchor will demonstrate no difference in loads to 2-mm displacement after cycling compared with first-generation all-soft suture anchors.

Study Design:

Controlled laboratory study.

Methods:

Twenty human cadaveric glenoids were utilized to create 97 total suture anchor sites, and 1 of 3 anchors were randomized and placed into each site: (1) first-generation all-soft suture anchor (Juggerknot; Biomet), (2) second-generation all-soft suture anchor (Suturefix; Smith & Nephew), and (3) a control PEEK anchor (Bioraptor; Smith & Nephew). After initial cyclic loading, load to 2 mm of displacement and ultimate load to failure were measured for each anchor.

Results:

After cyclic loading, the load to 2-mm displacement was significantly less in first-generation anchors compared with controls (P < .01). However, the load to 2-mm displacement was significantly greater in second-generation anchors compared with controls (P < .01). There was no difference in ultimate load to failure between the first- and second-generation all-soft suture anchors (P > .05).

Conclusion:

The newer generation all-soft suture anchors with a theoretically more rigid construct and deployment configuration demonstrate biomechanical characteristics (specifically, with load to 2-mm displacement after cyclic loading) that are improved over first-generation all-soft suture anchors and similar to a traditional solid tap-in anchor. The configuration of these newer generation all-soft suture anchors appears to mitigate the biomechanical concerns of decreased load to failure with first-generation all–soft tissue suture anchors.

Clinical Relevance:

The theoretical advantages of all-soft anchors may be particularly valuable in revision surgery or in cases where multiple anchors are being placed into a small anatomic area.

External rotation and active supination CT arthrography for the postoperative evaluation of type II superior labral anterior to posterior lesions

PURPOSE

To evaluate the effectiveness of external rotation and active supination CT arthrography in postoperative evaluation by comparing it with neutral CT arthrography and analyzing its agreement with postoperative clinical results after the repair of type II superior labral anterior to posterior (SLAP) lesions.

MATERIALS AND METHODS

A total of 25 patients who had undergone CT arthrography in neutral, external rotation and active supination position at least 1 year after the arthroscopic repair of SLAP lesions were enrolled. Two radiologists independently evaluated the status of the repaired SLAP lesions with neutral CT arthrography and then with external rotation and active supination CT arthrography.

RESULTS

Five patients had residual symptoms and positive findings upon SLAP-specific examinations. Agreements between the presence of symptoms and radiologic diagnoses based on neutral CT arthrography were insignificant for reader 1 (κ = 0.138, p = n.s.) and significant for reader 2 (κ = 0.328, p = 0.027). However, agreements were highly significant in the analysis following the evaluation of external rotation and active supination CT arthrography for both readers (κ = 0.694, p < 0.001 in reader 1; κ = 0.783, p < 0.001 in reader 2).

CONCLUSIONS

The presence of contrast-filled gaps between the labrum and glenoid on neutral CT arthrography after SLAP repair is frequent with satisfactory clinical outcomes. Gaps without additional widening upon external rotation and active supination CT arthrography may suggest postoperatively stable biceps anchors, so this new method could minimize the overdiagnosis of recurrent SLAP lesions. Additional gap widening on external rotation and active supination CT arthrography could be related to a true recurrent SLAP lesion and the symptoms of the patients.

LEVEL OF EVIDENCE

Case series, Level IV.

Graft osteolysis and recurrent instability after the Latarjet procedure performed with bioabsorbable screw fixation

HYPOTHESIS AND BACKGROUND

The Latarjet procedure is a reliable treatment of recurrent anterior shoulder instability. The coracoid process is usually fixed with metallic screws; however, these can lead to irritation and the necessity for hardware removal and also can produce artifacts on imaging studies. The use of resorbable screws could avoid these complications. The purpose of this study was to assess the clinical results of the Latarjet procedure performed with bioabsorbable screws in addition to healing of the graft and resorption of the screws.

METHODS

In 2009, we performed a prospective study (case series,

LEVEL OF EVIDENCE

IV) of 11 patients (12 shoulders) who underwent a Latarjet procedure fixed with resorbable screws. Each patient was observed clinically and had a computed tomography scan at 3 months and 2 years of follow-up.

RESULTS

Every graft healed at 3-month follow-up. At 2-year follow-up, 4 patients had at least one instability episode, and one underwent a revision surgery. Three of these 4 patients were unhappy or disappointed. The Walch-Duplay score was excellent or good for 7 shoulders and medium or poor for 5. Screw resorption appeared complete in every case. No drill hole enlargement was observed. Every drill hole was partially filled with bone. Of 12 shoulders, 8 (66.67%) were associated with a severe osteolysis and an almost complete disappearance of the graft.

CONCLUSION

Coracoid graft osteolysis, previously reported after the Latarjet procedure, appears to be exacerbated with a risk of complete disappearance of the graft when the procedure is performed with the bioabsorbable screws used in this study.

Magnetic resonance appearance of bioabsorbable anchor screws for double row arthroscopic rotator cuff repairs

BACKGROUND

Little is known about the bioabsorbable, anchor related postoperative changes in rotator cuff surgery, which has become more popular recently. The purpose of the present study was to use magnetic resonance imaging (MRI) to analyze the degradation of bioabsorbable anchors and to determine the incidences and characteristics of early postoperative reactions around the anchors and their mechanical failures.

MATERIALS AND METHODS

Postoperative MRIs of 200 patients who underwent arthroscopic rotator cuff repair were retrospectively analyzed. The tissue reactions around the bioanchors included fluid accumulations around the anchor, granulation tissue formation and changes in the condition of the surrounding osseous structure. The condition of the bioanchor itself was also examined, including whether the bioanchor failed mechanically. In the case of mechanical failure, the location of the failure was noted. Serial MRIs of 18 patients were available for analysis.

RESULTS

The total number of medial row bioanchors was 124, while that of the lateral row was 338. A low signal intensity rim suggestive of sclerosis surrounded all lateral row bioanchors. Ninety three lateral row bioanchors (27%) showed a rim with signal intensity similar to or less than that of surrounding bone, which was granulation tissue or foreign body reaction (FBR). Similar signal intensity was seen around nine medial row bioanchors (7%). Fluid accumulation was seen around 4 lateral row bioanchors (1%) and around 14 medial row bioanchors (11%). Five lateral row bioanchors showed the breakage, while there was none in the medial row bioanchors. There were nine cases with a cuff re-tear (4.5%). There was no evidence of affection of glenohumeral articular surfaces or of osteolysis around any bioanchor. In serial MRI, there was no change in appearance of the bioanchors, but the granulation tissue or FBR around four bioanchors and the fluid around one bioanchor showed a decrease in successive MRI.

CONCLUSION

This study highlights the normal and adverse reactions to Bioabsorbable anchors that surgeons can expect to see on MRI after rotator cuff repairs.

The arthroscopic treatment of shoulder instability: bioabsorbable and standard metallic anchors produce equivalent clinical results

PURPOSE

To investigate whether there are any differences in clinical outcomes and complications between absorbable and nonabsorbable suture anchors in the treatment of shoulder instability.

METHODS

We performed a comprehensive search of Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Embase, and the Cochrane Central Registry of Controlled Trials, from inception of the databases, using various combinations of keywords. Only studies focusing on clinical outcomes of patients who underwent arthroscopic shoulder stabilization with suture anchors were selected. Two authors (R.P. and L.D.B.) then evaluated the methodologic quality of each article using the Coleman Methodology Score.

RESULTS

Ten articles were included. Four were prospective randomized studies, 2 were prospective cohort studies, and 4 were case series. The mean modified Coleman Methodology Score was 76.2.

CONCLUSIONS

Given the overall good results reported after arthroscopic stabilization of the shoulder using different suture anchors, it is not possible to draw a definite and solid suggestion on which class of device is better advised for routine use. Thus the decision to use one of the anchor systems available may mostly depend on its cost-effectiveness, which should be the focus of future comprehensive research.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I to IV studies.

Factors affecting rotator cuff healing

Several studies have noted that increasing age is a significant factor for diminished rotator cuff healing, while biomechanical studies have suggested the reason for this may be an inferior healing environment in older patients. Larger tears and fatty infiltration or atrophy negatively affect rotator cuff healing. Arthroscopic rotator cuff repair, double-row repairs, performing a concomitant acromioplasty, and the use of platelet-rich plasma (PRP) do not demonstrate an improvement in structural healing over mini-open rotator cuff repairs, single-row repairs, not performing an acromioplasty, or not using PRP. There is conflicting evidence to support postoperative rehabilitation protocols using early motion over immobilization following rotator cuff repair.

Complications of arthroscopic shoulder surgery

Shoulder arthroscopic procedures have become common in today's orthopedic practice. The safety of shoulder arthroscopy though well established, is not without complications both minor and significant. The true incidence of complications is difficult to identify in the current literature. However, as with all procedures, complications associated with shoulder arthroscopy do occur. General complications (ie, infection), those specific to shoulder arthroscopy (ie, positioning) and those associated with specific procedures (ie, failure) all have been recognized. The purpose of this article is to review the current literature regarding complications in shoulder arthroscopy, provide insight into the risk factors and types of complications and to provide guidelines on the prevention and management of complications if and when they occur.

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.

Complications of bioabsorbable suture anchors in the shoulder

The development of the suture anchor has played a pivotal role in the transition from open to arthroscopic techniques of the shoulder. Various suture anchors have been manufactured that help facilitate the ability to create a soft tissue to bone repair. Because of reported complications of loosening, migration, and chondral injury with metallic anchors, bioabsorbable anchors have become increasingly used among orthopaedic surgeons. In this review, the authors sought to evaluate complications associated with bioabsorbable anchors in or about the shoulder and understand these in the context of the total number of bioabsorbable anchors placed. In 2008, 10 bioabsorbable anchor-related complications were reported to the US Food and Drug Administration. The reported literature complications of bioabsorbable anchors implanted about the shoulder include glenoid osteolysis, synovitis, and chondrolysis. These potential complications should be kept in mind when forming a differential diagnosis in a patient in whom a bioabsorbable anchor has been previously used. These literature reports, which amount to but a fraction of the total bioabsorbable anchors implanted in the shoulder on a yearly basis, underscore the relative safety and successful clinical results with use of bioabsorbable suture anchors. Product development continues with newer composites such as PEEK (polyetheretherketone) and calcium ceramics (tricalcium phosphate) in an effort to hypothetically create a mechanically stable construct with and improve biocompatibility of the implant. Bioabsorbable anchors remain a safe, reproducible, and consistent implant to secure soft tissue to bone in and about the shoulder. Meticulous insertion technique must be followed in using bioabsorbable anchors and may obviate many of the reported complications found in the literature. The purpose of this review is to provide an overview of the existing literature as it relates to the rare complications seen with use of bioabsorbable suture anchors in the shoulder.

Foreign-body reaction and osteolysis induced by an intraosseous poly-L-lactic Acid suture anchor in the wrist: case report

Polyglycolic acid and poly-L-lactic acid have become popular choices for bioabsorbable anchor fixation in the hand and wrist. We report a case of osteolysis, synovitis, and chondral erosion secondary to a poly-L-lactic acid suture anchor in the wrist.

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.

Arthroscopic repair of rotator cuff tears using absorbable anchors with a single-row technique

PURPOSE

To review outcomes of arthroscopic repair of rotator cuff tears using absorbable anchors with a single-row technique.

METHODS

66 patients underwent arthroscopic repair for rotator cuff tears using absorbable anchors with a single-row technique. 51 of them aged 37 to 73 (mean, 57) years had been followed up for a mean of 29 (range, 20-37) months. The extent of the tear was classified as large, medium or small. Functional outcome was assessed using the Constant score. Constant scores and re-tear rates in 3 patient groups (classified by patient age and tear size) were compared.

RESULTS

Among the 66 patients, there were 24 large, 29 medium and 13 small cuff tears, and a total of 48, 37, and 18 anchors were used, respectively. Among the 51 patients, the median Constant score improved significantly after arthroscopy (30 vs. 73, p<0.0001). Six shoulders had complete re-tears; their median Constant score was 48 and their adjusted Constant score was 65%. Complete re-tears occurred more often in patients aged >60 years than in those aged 50 to 59 years and <50 years (4/15 vs. 1/22 vs. 1/14), and more often in patients with large tears than in those with medium and small tears (4/24 vs. 2/29 vs. 0/13).

CONCLUSION

Arthroscopic repair of rotator cuff tears using absorbable anchors with a single-row technique is reliable in patients aged <60 years with small or medium tears.

Comparison between metal and biodegradable suture anchors in the arthroscopic treatment of traumatic anterior shoulder instability: a prospective randomized study

PURPOSE

The purpose of this study was to compare the clinical outcome of arthroscopic treatment of shoulder instability with metal and biodegradable suture anchors.

METHODS

Arthroscopic stabilization was performed in 78 patients with recurrent traumatic anterior shoulder instability. They were divided into 2 groups of 39 patients each, according to suture anchors used: metal anchors in group 1, and biodegradable anchors in group 2. Results were evaluated by use of the Disabilities of the Arm, Shoulder and Hand (DASH) self-administered questionnaire; Rowe score; Constant score normalized for age and gender, and recurrence of dislocation.

RESULTS

On analyzing the results at a 2-year follow-up, we considered the following independent variables: age; gender; arm dominance; duration of symptoms, age at first dislocation, number of dislocations, type of work; type of sport; sports activity level; lesion of the anterior labrum and anterior-inferior gleno-humeral ligament; SLAP lesion, and number of suture anchors. Comparison between groups did not show significant differences for each variable considered. Overall, according to the results, median DASH scores were 4.5 points (range 0-27) in group 1 and 7 points (range 0-25) in group 2 (n.s.); median Rowe scores were 100 points (range 60-100) and 100 points (range 25-100), respectively (n.s.); and median Constant scores were 98 points (range 81-107) and 98 points (range 87-121), respectively (n.s.). Recurrence was observed in 1 patient (2.8%) in group 1 and in 2 patients (5.9%) in group 2. Overall recurrence rate was 4.3%. Univariate and multivariate analysis showed that age, duration of symptoms, number of dislocations, type of work, and type of sports significantly and independently influenced the outcomes. Differences between groups 1 and 2 were not significant.

CONCLUSION

At a short-term follow-up, differences between arthroscopic shoulder stabilization with metal and biodegradable suture anchors were not statistically significant. Clinical relevance of the study is that there is no difference in the use of metal or biodegradable suture anchors for the arthroscopic treatment of shoulder instability.

Material properties and composition of soft-tissue fixation

Surgical interference screws and suture anchors for attaching soft tissue, such as ligaments and tendons, to bone are routinely used in arthroscopic surgery and sports medicine. Interference screw fixation provides a press fit between bone, graft/tendon, and screw and is frequently used to attach replacement ligaments in tunnels drilled for anterior and posterior cruciate ligament reconstruction. Suture anchors are used in surgical procedures wherein it is necessary for a surgeon to attach (tie) tissue to the surface of the bone, for example, during joint reconstruction and ligament repair or replacement. The composition of these implants ranges from metals to polymers and composites. Typically, because of the relatively large amount of torque that must be applied during insertion, these screws are constructed from metal. However, interference screws and suture anchors have also been constructed from bioabsorbable polymers and composites. The ideal material would (1) provide adequate mechanical fixation, (2) completely degrade once no longer needed, and (3) be completely replaced by bone. Because no material has been shown to be superior for all applications, the surgeon must weigh the advantages and disadvantages of each to evaluate the optimum material for a given application and patient. The purpose of this article is to present a comprehensive review of the commercially available interference screws and suture anchors, with an emphasis on implant composition, interaction, and design. This article provides the orthopaedic surgeon with a background on biomaterials, specifically those used in interference screws and suture anchors. Because there is no material that is perfect for all surgical situations, this review can be used to make educated decisions on a case-by-case basis.

"V"ictory transosseous equivalent suture configuration for arthroscopic rotator cuff tear repairs of iatrogenically completed PASTA lesions and full-thickness "U"-shaped tears

The cost of numerous anchors in rotator cuff surgery is high from both an economic standpoint as well as a physiologic one. More anchors means increased cost and increased surgical time; additionally, the greater number of anchors placed, the greater the expense on the native bone that they inevitably replace. It is therefore in the surgeon's and patient's best interest to use the appropriate number of anchors, no more and no less, with the appropriate number being that which allows for strong, stable fixation with minimal gap formation and maximal healing potential and recovery. The transosseous equivalent repair technique described herein uses a single double-loaded bioabsorbable suture anchor placed along the medial border of the rotator cuff foot print and the humeral head articular cartilage margin followed by 1 pushlock (Arthrex, Naples, Florida) anchor placed laterally on the vertical aspect of the greater tuberosity. It is designed for small to medium "U"-shaped tears and for iatrogenically completed partial articular supraspinatus tendon avulsions of moderate to large size, the so-called PASTA lesion. The use of selective knot placement allows for the conversion of a linear construct into a "V" configuration, optimizing repair strength and allowing for earlier rehabilitation while maximizing the healing biology seen with increased footprint contact dimensions and less repair gap formation.

Bioabsorbable anchors in glenohumeral shoulder surgery

The use of implants to provide glenohumeral soft tissue fixation has changed dramatically over the past few decades, from point tack fixation to metallic suture anchors to bioabsorbable suture anchors. Bioabsorbable suture anchors have largely replaced metallic anchors because of concerns of implant loosening, migration, and chondral injury. Although the safety and efficacy of bioabsorbable anchors has been well documented, there are numerous reports regarding the early failure related to implant bioabsorbable implant breakage or premature degradation. Patients with anchor-related complications generally present with pain and/or stiffness, and the surgeon should have a high index of suspicion if a patient does not progress as expected. Glenohumeral synovitis, glenoid osteolysis, loose bodies, and chondral injury are some of the notable complications that have been reported. Careful attention to proper anchor insertion techniques can limit the potential for complications. Newer materials, such as polyetheretherketone and other composites, have recently been introduced. These materials may address concerns of biocompatibility and material strength, but additional rigorous in vitro and in vivo trials need to be conducted before their use becomes widespread.

Suture anchor materials, eyelets, and designs: update 2008

PURPOSE

Our purpose was to evaluate recently introduced sutures and suture anchors for single pull load to failure strength and failure mode.

METHODS

Suture anchors were tested in fresh porcine metaphyseal cortex and cancellous troughs using an established protocol. An Instron machine applied tensile loads parallel to the axis of insertion at a rate of 12.5 mm per second until failure and mean anchor failure strengths were calculated. The mode of failure was recorded (anchor pullout, suture eyelet cut out, or suture failure). Anchors tested included the Kinsa, Kinsa RC, BioRaptor 2.3 PK, TwinFix PK FT 5.5 and 6.5, BioCleat, Healix Peek, VersaLok, BioKnotless, BioKnotless BR, Corkscrew FT III, SwiveLock C, and PEEK SutureTak.

RESULTS

The mean cortical failure loads were as follows: Kinsa (219 N), Kinsa RC (222 N), BioRaptor 2.3 PK (172 N), TwinFix PK FT 5.5 (491 N) and 6.5 (503 N), BioCleat (218 N), Healix Peek (407 N), VersaLok (376 N), BioKnotless (249 N), BioKnotless BR (265 N), Corkscrew FT III (386 N), SwiveLock C (712 N), and PEEK SutureTak (168 N). Pullout was the predominant failure mode for the VersaLok, BioKnotless, BioKnotless BR, and BioRaptor 2.3PK anchors. Eyelet failure was the predominant failure mode for the Kinsa, Kinsa RC, BioCleat, Healix Peek, Corkscrew FT III, SwiveLock C, and PEEK SutureTak.

CONCLUSIONS

The newer anchors showed markedly increased load to failure strengths. Two or more high-strength sutures are commonly used as well as new anchor materials (PEEK and Biocryl Rapide), new eyelet designs, and the increased use of a "knotless" concept.

CLINICAL RELEVANCE

An anchor which fails principally by pull out at a low load to failure is at risk for creating an intra-articular loose body.