Arthroscopic stabilization of the shoulder: a prospective randomized study of absorbable versus nonabsorbable suture anchors

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.

Survivorship and outcomes of arthroscopic bankart repair for anterior shoulder dislocations: A minimum of 2 year follow-up

Background

This study aims to evaluate long-term survivorship of arthroscopic Bankart repair (ABR).

Methods

About 101 patients under a single surgeon were followed up for ≥2 years post-ABR. Primary outcome was survivorship, defined as re-dislocation post-surgery. Secondary outcomes included a range of motion, strength, pain, University of California-Los-Angeles shoulder score, Oxford shoulder score (OSS), Oxford Shoulder Instability Score (OSIS), Constant Murley Score, and satisfaction. Clinical factors were correlated.

Results

Eight patients experienced postoperative dislocation (5 high-energy trauma, 2 low-energy trauma, 1 atraumatic), with 2 patients requiring revision. The mean time to post-operative dislocation was 1.5 years (range 0.3-3.8). Competitive athletes demonstrated worse survivorship (p = 0.027) but greater isometric strength at 6 months (p = 0.041) compared to recreational players. Patients ≥25 years old experienced slower recovery of internal rotation at 3 months (p = 0.006). Patients with surgery >1 year after injury had slower recovery of external rotation (p = 0.006), worse Constant scores at 3 months (p = 0.036) and lesser improvements in isometric strength at 3 months (p = 0.032). Patients with single pre-operative dislocations (p = 0.036 OSS; p = 0.039 OSIS) and patients ≥25 years old (p = 0.044 OSS) had worse Oxford scores at 3 months.

Discussion

ABR demonstrates good outcomes with low recurrence. This study prognosticates long-term outcomes across various subgroups.

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.

All-Suture Anchor vs. Knotless Suture Anchor for the Treatment of Anterior Shoulder Instability-A Prospective Cohort Study

All-suture or soft-anchors (SA) represent a new generation of suture anchor technology with a completely suture-based system. This study's objective was to assess Juggerknot® SA, for arthroscopic Bankart repair in recurrent shoulder instability (RSI), and to compare it to a commonly performed knotless anchor (KA) technique (Pushlock®). In a prospective cohort study, 30 consecutive patients scheduled for reconstruction of the capsulolabral complex without substantial glenoid bone loss were included and operated on using the SA technique. A historical control group was operated on using the KA technique for the same indication. Clinical examinations were performed preoperatively and 12 and 24 months postoperatively. RSI and WOSI at 24 months were the co-primary endpoints, evaluated with logistic and linear regression. A total of 5 out of 30 (16.7%) patients suffered from RSI in the SA group, one out of 31 (3.2%) in the KA group (adjusted odds ratio = 10.12, 95% CI: 0.89-115.35), and 13.3% in the SA group and 3.2% in the KAgroup had a revision. The median WOSI in the SA group was lower than in the KA group (81% vs. 95%) (adjusted regression coefficient = 10.12, 95% CI: 0.89-115.35). Arthroscopic capsulolabral repair for RSI using either the SA or KA technique led to satisfying clinical outcomes. However, there is a tendency for higher RSI and lower WOSI following the SA technique.

Arthroscopic Dynamic Anterior Stabilization Using Either Long Head of the Biceps or Conjoined Tendon Transfer for Anterior Shoulder Instability Results in a Similarly Low Recurrence Rate

PURPOSE

To compare the clinical outcomes of arthroscopic dynamic anterior stabilization (DAS) between transferring the long head of the biceps (DAS-LHB) and the conjoined tendon (DAS-CT) for anterior shoulder instability with <15% glenoid bone loss.

METHODS

From January 2016 to May 2019, a total of 63 patients who underwent DAS for recurrent anterior shoulder dislocation with <15% glenoid bone loss were included, comprising 33 patients in DAS-LHB group and 30 patients in DAS-CT group. Clinical outcomes were assessed preoperatively and at a minimum 3-year follow-up, including patient-reported outcomes, range of motion, and return to sports (RTS). Postoperative recurrent instability (including dislocation, subluxation, and subjective instability with a positive apprehension test), revisions and complications also were recorded.

RESULTS

No significant demographic characteristics difference was detected between the DAS-LHB (26.3 ± 7.9 years) and DAS-CT groups (26.0 ± 6.7 years). At the latest follow-up, there were no significant differences between the 2 groups in functional scores: Oxford Shoulder Instability Score (14.8 ± 2.8 vs 15.2 ± 3.6), Rowe score (95.9 ± 6.5 vs 93.2 ± 10.2), visual analog scale for pain (0.8 ± 1.2 vs 0.7 ± 1.7), and American Shoulder and Elbow Surgeons (95 ± 8.8 vs 95.2 ± 9.1) (all P > .218). No significant difference was detected between groups in the rates of RTS (90.1% vs 86.7%, P = .700) and RTS at previous level (78.7% vs 73.3%, P = .258), respectively. No recurrent dislocation occurred in either group. One patient felt occasional subluxation in the DAS-LHB group, and one was positive for the apprehension test in each group. One patient presented with postoperative shoulder stiffness and underwent a secondary arthroscopic debridement in the DAS-CT group.

CONCLUSIONS

Comparable rates of recurrence, complication, return to sports, and subjective shoulder function were observed between DAS-LHB and DAS-CT groups.

LEVEL OF EVIDENCE

Ⅲ; retrospective comparative therapeutic trial.

Determining the Minimal Clinically Important Difference on the Oxford Shoulder Instability Score in Patients Undergoing Arthroscopic Bankart Repair for Shoulder Instability

Background:

The literature on minimal clinically important differences (MCIDs) for patient-reported outcome measures assessing shoulder instability is limited, with none addressing the Oxford Shoulder Instability Score (OSIS). The OSIS was developed to provide a standardized method for assessing shoulder function after surgery for shoulder instability, and previous studies have demonstrated its high reliability, low interrater variability, and ease of administration.

Purpose:

To identify the MCID for the OSIS after arthroscopic Bankart repair for recurrent shoulder instability.

Study Design:

Case series; Level of evidence, 4.

Methods:

A longitudinally maintained institutional registry was queried for patients who underwent arthroscopic Bankart repair from 2010 to 2016 for recurrent shoulder instability secondary to a Bankart lesion without significant glenoid bone loss. The OSIS was completed preoperatively and at 1 year postoperatively. Patients were categorized into “expectations met” and “expectations unmet” groups using a questionnaire evaluating expectation fulfilment. The MCID of the OSIS at 1 year was calculated using 3 anchor-based approaches and a distribution-based approach. The 3 anchor-based approaches comprised (1) simple linear regression analysis, (2) receiver operating characteristic curve analysis, and (3) calculation of mean differences in change for the OSIS between the “expectations met” and “expectations unmet” groups.

Results:

The study cohort comprised 68 men and 11 women aged 29.9 ± 12.7 years (mean ± SD). Duration of follow-up for all patients exceeded 1 year. The MCIDs for the OSIS based on the 4 calculation approaches yielded a narrow range of values, ranging from 7.7 to 8.5 for the anchor-based methods and 8.6 for the distribution-based method.

Conclusion:

Study results indicated that patients with recurrent shoulder instability without significant bone loss who undergo primary arthroscopic Bankart repair and have at least 8.6 points of improvement on their OSIS experience a clinically significant change at 1 year postoperatively.

Recurrent Instability after Arthroscopic Glenoid Labral Repair with a Minimum of Three Points of Fixation: Do the Number of Anchors or Fixation Points Correlate to Outcomes?

INTRODUCTION

The goal of this study was to evaluate the recurrence rate of instability following arthroscopic Bankart repairs in regard to the number and types of fixation utilized. A Bankart lesion is a tear in the anteroinferior capsulolabral complex within the shoulder, occurring in association with an anterior shoulder dislocation. These injuries can result in glenoid bone loss, decreased range of motion, and recurrent shoulder instability. Successful repair of these lesions has been reported in the literature with repair constructs that have three points of fixation. However, the definition of "one point of fixation" is yet to be fully elucidated.

MATERIALS AND METHODS

A consecutive series of arthroscopically repaired Bankart lesions were evaluated pertaining to the points of fixation required to achieve shoulder stability. This included the number, position, and types of anchors used. Patients consented to complete a series of surveys at a minimum of two years postoperatively. The primary outcome was to determine recurrent instability via the UCLA Shoulder Score, the ROWE Shoulder Instability Score, and the Oxford Shoulder Score. A secondary outcome included pain on a Visual Analog Scale (VAS).

RESULTS

There were 116 patients reviewed, 46 patients achieved three points of fixation in their surgical repair via two anchors and 70 patients achieved a similar fixation with three or more anchors. There was no significant difference in the mean age, gender, or body mass index (BMI). Patients receiving two anchors demonstrated recurrent instability 8.7% of the time (4 of 46 patients). Patients who received three or more anchors demonstrated recurrent instability 8.6% of the time (6 of 70 patients). Overall, there was no statistical significance between the number/types of anchors used. Between the two cohorts, there was no statistically significant difference found between VAS, ROWE, UCLA, and Oxford Scores. There was a significant difference in pain reported on the VAS scale with an average VAS score of 0.43 versus 2.5 in those without and with recurrent instability respectively.

CONCLUSION

Contention still exists surrounding the exact definition of "a point of fixation" in arthroscopic Bankart repairs. Three-point constructs can be created through a variety of combinations including anchors and sutures, ultimately achieving the goal of a stable shoulder.

Comparison between all-suture and biocomposite anchors in the arthroscopic treatment of traumatic anterior shoulder instability: A retrospective cohort study

Purpose

Suture anchors have revolutionized arthroscopic surgery, enabling direct soft tissue-to-bone repair. There are many types of anchors still used in arthroscopic shoulder operations. We sought to compare the clinical outcome of all-suture and biocomposite anchors when used in arthroscopic Bankart repair for patients suffering from anterior shoulder instability.

Methods

A single-center retrospective cohort study of 30 patients (mean age: 26.6 years, SD: 8.8 years, male/female ratio: 5/1, mean follow up: 28 months, SD: 23.8, range: 12-92) with anterior shoulder instability was conducted. Patients were divided into 2 groups based upon the type of suture anchors used for the Bankart repair: group A (14 patients) used only all-suture anchors and group B (16 patients) used only biocomposite anchors. Outcomes reported were postoperative dislocations, positive shoulder apprehension test, self-reported sense of shoulder instability, return to activities of daily living, return to sports, patient satisfaction and complications. Patient reported outcome measures (PROMs) used were the Rowe Score for Instability, Constant Shoulder Score, Walch Duplay Score, The American Shoulder and Elbow Surgeons (ASES) Shoulder Score, Oxford Shoulder Instability Score and external rotation at 90° of arm abduction, external rotation at 0° of arm abduction, forward flexion, abduction, adduction and internal rotation.

Results

Rates of postoperative shoulder dislocation demonstrated no significant difference between the 2 groups (p > .05). Four postoperative dislocations happened, two in each group (14.3% and 12.5% for all suture only and biocomposite only groups, respectively), with three of them being traumatic. In addition, no significant differences were observed amongst groups regarding shoulder apprehension test (group A: 85.7% vs. group B: 93.8%), sense of shoulder instability (7.1% vs. 6.3%), return to activities of daily living (group A: 85.7% vs. group B: 93.8%), return to sports (group A: 85.7% vs. group B: 87.5%), patient satisfaction (moderate level: group A 21.4% vs. group B 12.5%), and PROMs.

Conclusion

The short-term failure rate and clinical/functional outcomes of arthroscopic Bankart repair using all-suture anchors is similar to the use of biocompatible anchors.

Level of evidence

Level III, retrospective cohort study.

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.

Double-loaded suture anchors in the treatment of anteroinferior glenohumeral instability

Hypothesis

The purpose of this study was to determine the clinical outcomes of arthroscopic labral repair for anteroinferior glenohumeral instability with the use of double-loaded suture anchors.

Methods

This study evaluated a series of consecutive patients treated after the senior author changed from single- to double-loaded suture anchors for the treatment of anteroinferior glenohumeral instability with a minimum follow-up period of 2 years. We collected the following outcomes at final follow-up: visual analog scale pain score, Simple Shoulder Test score, American Shoulder and Elbow Surgeons score, and instability recurrence data.

Results

A total of 41 consecutive patients underwent arthroscopic labral repair with double-loaded anchors, of whom 30 (71%) were able to be contacted at a minimum of 2 years postoperatively. These patients included 4 contact or collision athletes (13%). The patients had an average of 12 ± 13 prior dislocations over an average period of 56 ± 57 months preoperatively. Mean glenoid bone loss measured 16% ± 10%, and 67% (18 of 27 patients) had glenoid bone loss ≥ 13.5%. Intraoperatively, 3.2 ± 0.4 anchors were used. No posterior repairs or remplissage procedures were performed. At an average of 6.7 ± 2.7 years' follow-up, the visual analog scale pain score was 0.8 ± 1.4; Simple Shoulder Test score, 11 ± 2; and American Shoulder and Elbow Surgeons score, 90 ± 14. Patients with bone loss < 13.5% had a 0% redislocation rate and 11% subluxation rate, whereas those with bone loss ≥ 13.5% had a 6% reoperation rate, 22% redislocation rate, and 22% subluxation rate.

Conclusion

Arthroscopic labral repair with double-loaded anchors provides satisfactory clinical results at early to mid-term outcome assessment when glenoid bone loss is <13.5%.

Outcome Measures After Shoulder Stabilization in the Athletic Population: A Systematic Review of Clinical and Patient-Reported Metrics

Background:

Athletic endeavor can require the “athletic shoulder” to tolerate significant load through supraphysiological range and often under considerable repetition. Outcome measures are valuable when determining an athlete’s safe return to sport. Few data are available to guide a clinician’s choice from the variety of measures available.

Purpose:

To describe the use of quantifiable objective outcome measures and patient-reported outcome tools after glenohumeral joint stabilization, specifically in an athletic population. The secondary aim of our study was to assess whether the method of measurement used was clearly described and standardized to aid clinical interpretation.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic search of MEDLINE, Scopus, SPORTDiscus, and Web of Science databases was performed in December 2018 based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. After the application of selection criteria, a full review of identified papers, and screening of reference lists, a total of 62 studies were included in the review. All studies were independently appraised for quality, predefined data fields were populated and cross-checked for accuracy, and results were then summarized from these data fields.

Results:

Of the 62 included studies, 94% used a quantifiable objective clinical outcome. A majority (85%) of the studies measured range of motion, 21% recorded muscle strength, 5% measured electromyographic activity, 5% examined shoulder kinematics, and 3% assessed joint proprioception after surgery. However, only 18% of the studies clearly described a standardized method of measuring the outcome. Nearly all (95%) of the studies used at least 1 patient-reported outcome measure. The Rowe score was most commonly used (35%).

Conclusion:

We must standardize and clearly describe the use of quantifiable objective outcome measures to aid clinical interpretation. A concerted effort should also be made to standardize the use of patient-reported outcome tools after shoulder stabilization in the athletic population.

Editorial Commentary: Innovations in Anchor Design-Are Patients Really Benefiting?

Vented open-architecture suture anchors provide theoretical benefits over traditional screw-in solid anchors to include improved osseous ingrowth, elution of marrow elements to enhance biology at the repair site, and easier revision because of reduced anchor material. However, there is no evidence that open-architecture anchors result in improvements in patient-reported outcomes or early cytokine and marrow element release into the subacromial space compared with traditional screw-in solid anchors. Although innovation and evaluation of new technologies are paramount to surgical progress, decisions on implant use should be based on factors including cost, impact on revision, and surgeon familiarity because frequently, clinical differences based on patient-reported outcomes are not appreciated between anchor types or designs.

History of surgical stabilization for posterior shoulder instability

Background

Posterior shoulder instability is common in young athletes. Although the posterior shoulder instability literature is less robust than its anterior counterpart, many surgical procedures have been developed and refined over the past several centuries to address this condition.

Materials and methods

This article represents a retrospective historical analysis of the most common procedures used to treat posterior shoulder instability after sports injuries. A systematic approach to obtain published information on posterior shoulder instability was performed using the PubMed/MEDLINE database, manual searches of high–impact factor journals, and conference proceedings and books.

Results

A wide array of both soft tissue–based and bone-based procedures have been developed for the treatment of posterior shoulder instability, ranging from procedures addressing the soft tissue alone (capsular shift, labral repair, reverse Putti-Platt) or bone-based procedures (glenoid and/or humeral osteotomy, glenoid bone block) to a combination of both bone and soft-tissue procedures (modified McLaughlin procedure).

Discussion

Over the past several centuries, a number of procedures have been developed to address posterior shoulder instability, particularly as this pathology has become better understood. Future work is required not only to continue to advance these procedures but also to assess their outcomes. An understanding of the historical perspective of posterior shoulder instability procedures is essential as surgeons continue to modify these procedures in an effort to best help their patients.

Metallic versus biodegradable suture anchors for rotator cuff repair: a case control study

BACKGROUNDS

Repair of full-thickness rotator cuff (RC) tears is routinely performed using suture anchors, which produce secure and effective soft tissue fixation to bone. The aim of this prospective study is to compare the long-term outcomes of single row arthroscopic rotator cuff repair (RCR) performed using metal or biodegradable suture anchors. The null hypothesis is that there is no difference in shoulder function using metal or biodegradable suture anchors as evaluated by UCLA shoulder score, Wolfgang criteria, and Oxford shoulder score.

METHODS

Arthroscopic RCR was performed in 110 patients included in this case control study. They were divided into 2 groups of 51 and 59 patients respectively. Metal suture anchors were used in group 1, and biodegradable suture anchors in group 2. Results were obtained at a mean follow up of 4.05 + 2 years. Clinical outcomes and functional outcomes were evaluated.

RESULTS

The mean modified UCLA shoulder score was 26.9 + 7.1 in group 1, and 27.7 + 6.5 in group 2 (P = 0.5); the mean Wolfgang score was 13.3 + 3.3 in group 1, and 14 + 2.6 in group 2 (P = 0.3); the mean OSS was 23.7 + 11.4 in group 1, and 20.7 + 9.2 points in group 2 (P = 0.1). The mean active anterior elevation was 163.5° + 28.2° in group 1 and 163.6° + 26.9 in group 2 (P = 0.9); the mean active external rotation was 46° + 19.7° in group 1 and 44.6° + 16.3° in group 2 (P = 0.7). The mean strength in anterior elevation was 4.8.02 + 23.52 N in group 1, and 43.12 + 17.64 N in group 2 (P = 0.2); the mean strength in external rotation was 48.02 + 22.54 N in group 1 and 46.06 + 17.64 N in group 2 (P = 0.6); the mean strength in internal rotation was 67.62 + 29.4 N in group 1, and 68.6 + 25.48 N in group 2 (P = 0.9).

CONCLUSIONS

There are no statistically significant differences at a mean follow-up of 4.05 + 2 years in clinical and functional outcomes of single row arthroscopic RCR using metallic or biodegradable suture anchors for RC < 5 cm.

Anchor Hole Placement for Bankart Repairs and Its Interaction With Variable Size Hill–Sachs Defects-Minimizing Risk of Glenoid Rim Fractures

As the use of glenoid suture anchors in arthroscopic and open reconstruction, for instability after Bankart lesions of the shoulder, increases, an emerging problem has been the incidence of glenoid rim fractures through suture drill holes. Very little is known regarding the effect of the Hill–Sachs lesion on the glenoid's susceptibility to fracture and how drill hole location can further affect this. This study used finite element modeling techniques to investigate the risk of fracture of the glenoid rim in relation to variable sized Hill–Sachs defects impacting on the anterior glenoid edge with suture anchor holes placed in varying positions. The distribution of Von Mises (VM) stresses and the factor of safety (FOS) for each of the configurations were calculated. The greatest peak in VM stresses was generated when the glenoid was loaded with a small Hill–Sachs lesion. The VM stresses were lessened and the FOS increased (reducing likelihood of failure) with increasing size of the Hill–Sachs lesion. Placement of the suture drill holes at 2 mm from the glenoid rim showed the highest risk of failure; and when combined with a medium sized Hill–Sachs lesion, which matched the central line of the drill holes, a potentially clinically significant configuration was presented. The results of this study are useful in assisting the surgeon in understanding the interaction between the Hill–Sachs lesion size and the placement of suture anchors with the purpose of minimizing the risk of subsequent rim fracture with new injury.

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.

Cytotoxicity and biomechanics of suture anchors used in labral repairs

Background

Biodegradable suture anchors are associated with higher redislocation rates. This study examined whether the biocompatibility and/or biomechanical properties of suture anchors contribute to the increase in complications.

Methods

Human glenohumeral capsule cells were cultured with 4 types of suture anchors, Opus LabraFix (titanium alloy; ArthroCare, Austin, TX, USA), PushLock (poly-ether-ether-ketone; Arthrex, Naples, FL, USA), BioKnotless (poly-l-lactic acid; DePuy Mitek, Warsaw, IN, USA), and Suretac II (polyglycolic acid; Smith & Nephew, London, UK), to measure cell viability and pH. Four groups of 6 ovine shoulders were used to repair the labrum, which was completely detached from the glenoid rim anteroinferiorly and reattached with 2 suture anchors and subject to failure load testing.

Results

In cell culture, BioKnotless at 48 and 72 hours (85.2% ± 2.1% and 84.5% ± 3.6%) and Suretac II groups (33.9% ± 3.1% and 42.8% ± 6.4%) had fewer viable cells compared with control (P = .048). The pH of Suretac II was lower than control (7.51 to 7.65) at 24 hours (7.31 ± 0.08, P = .049), 48 hours (7.25 ± 0.02, P = .046), and 72 hours (7.29 ± 0.04, P = .04). During mechanical testing, 83% of repairs failed by the capsule tearing. Among the anchors, the BioKnotless repair group had a significantly lower failure load (37 ± 5 N) compared with the PushLock (61 ± 7 N), Opus (60 ± 6 N), and Suretac II (57 ± 7 N) groups (P = .038).

Conclusion

BioKnotless and Suretac II anchors are cytotoxic. The BioKnotless biodegradable anchor has significantly lower failure load. Absorbable suture anchors may cause higher redislocation of arthroscopic Bankart repair.

Surgical treatment outcomes after primary vs recurrent anterior shoulder instability

INTRODUCTION

The aim of this study is to compare the outcomes of surgical management after primary anterior shoulder dislocation to the outcomes of patients who have surgical stabilization after recurrent anterior shoulder instability.

METHODS

A Medline (PubMed) search was performed in November of 2016 using the following key terms: shoulder, labrum, Bankart, instability, repair, outcome, recurrent. In May 2017 a Cochrane search was performed using similar key terms to ensure we included all studies. Only level I and II studies were included.

RESULTS

There were three studies that compared primary repair to delayed repair. In all three studies, the rate of recurrence was higher in group R than group S. When pooled, there was not a statistically significant difference between these groups, but there was a slightly higher odds of recurrence in group R (pooled OR 2.08, CI 0.69-6.26, p = 0.19). No significant differences were appreciated in functional outcomes or complications in these two groups.

CONCLUSION

Further level I and level II studies to compare surgical treatment after first time and recurrent instability are needed. This study failed to find a statistically significant difference in recurrence rates in patients who had stabilization acutely after a single episode compared to patients with recurrent instability events, although results suggest there may be a small benefit in primary stabilization.

Treatment after traumatic shoulder dislocation: a systematic review with a network meta-analysis

OBJECTIVE

To review and compare treatments (1) after primary traumatic shoulder dislocation aimed at minimising the risk of chronic shoulder instability and (2) for chronic post-traumatic shoulder instability.

DESIGN

Intervention systematic review with random effects network meta-analysis and direct comparison meta-analyses.

DATA SOURCES

Electronic databases (Ovid MEDLINE, Cochrane Clinical Trials Register, Cochrane Database of Systematic Reviews, Embase, Scopus, CINAHL, Ovid MEDLINE Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Ovid MEDLINE Daily, DARE, HTA, NHSEED, Web of Science) and reference lists were searched from inception to 15 January 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised trials comparing any interventions either after a first-time, traumatic shoulder dislocation or chronic post-traumatic shoulder instability, with a shoulder instability, function or quality of life outcome.

RESULTS

Twenty-two randomised controlled trials were included. There was moderate quality evidence suggesting that labrum repair reduced the risk of future shoulder dislocation (relative risk 0.15; 95% CI 0.03 to 0.8, p=0.026), and that with non-surgical management 47% of patients did not experience shoulder redislocation. Very low to low-quality evidence suggested no benefit of immobilisation in external rotation versus internal rotation. There was low-quality evidence that an open procedure was superior to arthroscopic surgery for preventing shoulder redislocations.

CONCLUSIONS

There was moderate-quality evidence that half of the patients managed with physiotherapy after a first-time traumatic shoulder dislocation did not experience recurrent shoulder dislocations. If chronic instability develops, surgery could be considered. There was no evidence regarding the effectiveness of surgical management for post-traumatic chronic shoulder instability.

An assessment of quality of randomized controlled trials in shoulder instability surgery using a modification of the clear CLEAR-NPT score

BACKGROUND

The present study aimed to evaluate the methodological quality and determine the quality of reporting of randomized controlled trials (RCTs) that assess surgical treatment for shoulder instability.

METHODS

A Cochrane, Pubmed, EMBASE and Trip database search was performed, including the relevant literature, regarding RCTs that report on shoulder instability published between January 1994 and January 2017. Methodological quality was assessed with a modification of the Checklist to Evaluate A Report of a Nonpharmacologic Trial (CLEAR-NPT). Points were assigned based on 18 items regarding patient characteristics, randomization, care provider characteristics, surgical details and blinding, with a total score ranging from 0 points to 18 points. Missing items were verified with the corresponding authors of the studies. Quality of reporting corresponds to the total scores including the items that were additionally provided by the authors.

RESULTS

We included 22 studies. Of these, nine corresponding authors provided additional information. The average methodological quality was 16.9 points (11 studies) and the average quality of reporting was 9.5 points (22 studies). Items scoring worst included information regarding the surgeon's experience, the patients' level of activity, comorbidities, analyzing according to 'intention-to-treat' principles, and blinding of care providers, participants and assessors.

CONCLUSIONS

RCTs reporting on shoulder instability surgery are well performed but poorly reported.

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.

Degradation of Cylindrical Poly-Lactic Co-Glycolide/Beta-Tricalcium Phosphate Biocomposite Anchors After Arthroscopic Bankart Repair: A Prospective Study

The purpose of this study was to examine widening and ossification of anchor holes after arthroscopic Bankart repair with the use of cylindrical biocomposite anchors made of 70% poly-L-lactide-co-glycolide acid (PLGA) and 30% beta-tricalcium phosphate (ß-TCP). Twenty-two patients were enrolled in a clinical trial to acquire marketing approval of a PLGA/ß-TCP biocomposite suture anchor in Japan and underwent arthroscopic Bankart repairs with the anchors. Eleven of 22 patients had computed tomography scans after 2-year follow-up. Three surgeons independently evaluated width and ossification of anchor holes in 4 grades using computed tomography scans. When the evaluations disagreed, the final grade was determined based on the 3 surgeons' consensus. Seven men and 4 women were evaluated at a mean of 30 months (range, 28-32 months) after surgery, and a total of 47 anchors were implanted. Anchor holes were narrowed in 39 (83%) of 47 anchor sites and were almost or completely filled in (type 3 or 4) in 21 (45%) of 47 anchor sites. Ossification was seen in 46 (98%) of 47 anchor sites and was nearly complete or complete (type 3 or 4) in 16 (34%) of 47 anchor sites. There were no significant differences in both anchor hole width and ossification score on comparison of the anteroinferior (4- to 6-o'clock positions in the right shoulder) with other anchor sites. Cylindrical biocomposite anchors made of 70% PLGA/30% ß-TCP showed a low incidence of anchor hole widening and excellent ossification regardless of anchor site. [Orthopedics. 2018; 41(3):e348-e353.].

Recurrent Instability After Arthroscopic Bankart Reconstruction: A Systematic Review of Surgical Technical Factors

PURPOSE

Recurrent instability remains of concern after arthroscopic Bankart reconstruction. We evaluated various technical factors including anchor design, anchor material, number of anchors used, and interval closure on risk of recurrent instability after arthroscopic Bankart reconstruction.

METHODS

A systematic review of MEDLINE and Cochrane databases was conducted, following PRISMA guidelines. Extracted data were recorded on a standardized form. Methodological index for non-randomized studies (MINORS) and Newcastle-Ottawa Scale (NOS) were used to assess study quality and risk bias. Because of study heterogeneity and low levels of evidence, meta-analysis was not possible. Pooled weighted means were calculated and individual study evaluation and comparisons (qualitative analysis) were performed for systematic review.

RESULTS

Of 2097 studies identified, 26 met criteria for systematic review. Pooled weighted means revealed 11.4% versus 15% recurrent instability with 3 or more suture anchors versus fewer than 3 anchors, 10.1% versus 7.8% with absorbable versus nonabsorbable suture anchors, respectively, and 8.0% versus 9.4% with knotless versus standard anchors, respectively. Interval closure did not qualitatively decrease recurrent instability or decrease range of motion.

CONCLUSIONS

Our systematic review reveals that despite individual study, and previous systematic reviews pointing to the contrary, the composite contemporary published literature would support no difference in the risk of recurrent instability after arthroscopic Bankart reconstruction with rotator interval closure, differing numbers of anchors used for the repair, use of knotless versus standard anchors, or use of bioabsorbable versus nonabsorbable anchors. We recommend surgeons focus on factors that have been shown to modify the risk factors after arthroscopic Bankart reconstruction, such as patient selection.

LEVEL OF EVIDENCE

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

An Anatomic and Biomechanical Comparison of Bankart Repair Configurations

BACKGROUND

Suture anchor repair for anterior shoulder instability can be performed using a number of different repair techniques, but none has been proven superior in terms of anatomic and biomechanical properties. Purpose/Hypothesis: The purpose was to compare the anatomic footprint coverage and biomechanical characteristics of 4 different Bankart repair techniques: (1) single row with simple sutures, (2) single row with horizontal mattress sutures, (3) double row with sutures, and (4) double row with labral tape. The hypotheses were as follows: (1) double-row techniques would improve the footprint coverage and biomechanical properties compared with single-row techniques, (2) horizontal mattress sutures would increase the footprint coverage compared with simple sutures, and (3) repair techniques with labral tape and sutures would not show different biomechanical properties.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty-four fresh-frozen cadaveric specimens were dissected. The native labrum was removed and the footprint marked and measured. Repair for each of the 4 groups was performed, and the uncovered footprint was measured using a 3-dimensional digitizer. The strength of the repair sites was assessed using a servohydraulic testing machine and a digital video system to record load to failure, cyclic displacement, and stiffness.

RESULTS

The double-row repair techniques with sutures and labral tape covered 73.4% and 77.0% of the footprint, respectively. These percentages were significantly higher than the footprint coverage achieved by single-row repair techniques using simple sutures (38.1%) and horizontal mattress sutures (32.8%) ( P < .001). The footprint coverage of the simple suture and horizontal mattress suture groups was not significantly different ( P = .44). There were no significant differences in load to failure, cyclic displacement, or stiffness between the single-row and double-row groups or between the simple suture and horizontal mattress suture techniques. Likewise, there was no difference in the biomechanical properties of the double-row repair techniques with sutures versus labral tape.

CONCLUSION

Double-row repair techniques provided better coverage of the native footprint of the labrum but did not provide superior biomechanical properties compared with single-row repair techniques. There was no difference in footprint coverage or biomechanical strength between the simple suture and horizontal mattress suture repair techniques.

CLINICAL RELEVANCE

Although the double-row repair techniques had no difference in initial strength, they may improve healing in high-risk patients by improving the footprint coverage.

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.

Anatomic and Biomechanical Comparison of Traditional Bankart Repair With Bone Tunnels and Bankart Repair Utilizing Suture Anchors

Background:

Traditional Bankart repair using bone tunnels has a reported failure rate between 0% and 5% in long-term studies. Arthroscopic Bankart repair using suture anchors has become more popular; however, reported failure rates have been cited between 4% and 18%. There have been no satisfactory explanations for the differences in these outcomes.

Hypothesis:

Bone tunnels will provide increased coverage of the native labral footprint and demonstrate greater load to failure and stiffness and decreased cyclic displacement in biomechanical testing.

Study Design:

Controlled laboratory study.

Methods:

Twenty-two fresh-frozen cadaveric shoulders were used. For footprint analysis, the labral footprint area was marked and measured using a Microscribe technique in 6 specimens. A 3-suture anchor repair was performed, and the area of the uncovered footprint was measured. This was repeated with traditional bone tunnel repair. For the biomechanical analysis, 8 paired specimens were randomly assigned to bone tunnel or suture anchor repair with the contralateral specimen assigned to the other technique. Each specimen underwent cyclic loading (5-25 N, 1 Hz, 100 cycles) and load to failure (15 mm/min). Displacement was measured using a digitized video recording system.

Results:

Bankart repair with bone tunnels provided significantly more coverage of the native labral footprint than repair with suture anchors (100% vs 27%, P < .001). Repair with bone tunnels (21.9 ± 8.7 N/mm) showed significantly greater stiffness than suture anchor repair (17.1 ± 3.5 N/mm, P = .032). Mean load to failure and gap formation after cyclic loading were not statistically different between bone tunnel (259 ± 76.8 N, 0.209 ± 0.064 mm) and suture anchor repairs (221.5 ± 59.0 N [P = .071], 0.161 ± 0.51 mm [P = .100]).

Conclusion:

Bankart repair with bone tunnels completely covered the footprint anatomy while suture anchor repair covered less than 30% of the native footprint. Repair using bone tunnels resulted in significantly greater stiffness than repair with suture anchors. Load to failure and gap formation were not significantly different.

Evaluation of postoperative results from videoarthroscopic treatment for recurrent shoulder dislocation using metal anchors

OBJECTIVE

To clinically and radiologically evaluate the results from videoarthroscopic treatment using metal anchors in patients with recurrent shoulder dislocation and its complications.

METHODS

This was a retrospective study on 47 patients (47 shoulders) operated by the shoulder group of the orthopedic hospital between February 2010 and February 2012. A questionnaire, interview and physical and radiographic examinations were used, with the classification of Samilson and Pietro. The mean postoperative follow-up was 33 months (range 12-47 months). The statistical analysis consisted of using Fisher's exact test through the IBM SPSS 22 statistical software. The significance level used was 5%.

RESULTS

Recurrence was observed in nine cases. The patients were, on average, 26.5 years old at the first episode, and 19.1% were aged 20 years or under. Among these, 55.6% presented recurrence. In relation to age at the time of the surgical procedure, the average age was 27 years, and 12.8% were aged 20 years or under. Nineteen patients presented prominent anchors and, of these, 21% manifested arthrosis.

CONCLUSION

There was a statistically identified correlation between the recurrence rate and age less than or equal to 20 years at the times of first dislocation and the surgical procedure. Further studies should be conducted in order to compare the use of absorbable anchors, which despite higher cost, may provide lower risk of developing glenohumeral arthrosis in some cases.

The Oxford Shoulder Instability Score; validation in Dutch and first-time assessment of its smallest detectable change

Background

The Oxford Shoulder Instability Score (OSIS) is a short, self-reported outcome measurement for patients with shoulder instability.

In this study, the OSIS was validated in Dutch by testing the internal consistency, reliability, measurement error, validity and the floor and ceiling effects, and its smallest detectable change (SDC) was calculated.

Methods

A total of 138 patients were included. Internal consistency was calculated with Cronbach’s α. Reliability (test-retest) was calculated with the intraclass correlation coefficient (ICC). The measurement error was calculated (SEM), and the SDC was estimated in a subgroup of 99 patients that completed the re-test after a mean of 13 days (5–30 days). Construct validity was evaluated by comparing the OSIS with the Western Ontario Shoulder Instability index (WOSI), the Simple Shoulder Test (SST), the Oxford Shoulder Score (OSS), the Disability of the Arm, Shoulder, and Hand assessment (DASH), and the Short Form-36 (SF-36).

Results

Internal consistency was good, with a Cronbach’s α of 0.88. The reliability was excellent, with an ICC of 0.87. The SEM was 3.3 and the SDC was 9 points (on a scale of 0–48). Regarding the construct validity, 80 % of the results were in accordance with the hypotheses, including a high correlation (0.82) with the WOSI. No floor or ceiling effects were found.

Conclusions

The Dutch version of the OSIS showed good reliability and validity in a cohort of patients with shoulder instability.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-015-0286-5) contains supplementary material, which is available to authorized users.

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.

Results of 45 arthroscopic Bankart procedures: Does the ISIS remain a reliable prognostic assessment after 5 years?

PURPOSE

The Instability Severity Index Score (ISIS) includes preoperative clinical and radiological risk factors to select patients who can benefit from an arthroscopic Bankart procedure with a low rate of recurrence. Patients who underwent an arthroscopic Bankart for anterior shoulder instability with an ISIS lower than or equal to four were assessed after a minimum of 5-year follow-up.

METHODS

Forty-five shoulders were assessed at a mean of 79 months (range 60-118 months). Average age was 29.4 years (range 17-58 years) at the time of surgery. Postoperative functions were assessed by the Walch and Duplay and the Rowe scores for 26 patients; an adapted telephonic interview was performed for the 19 remaining patients who could not be reassessed clinically. A failure was defined by the recurrence of an anterior dislocation or subluxation. Patients were asked whether they were finally very satisfied, satisfied or unhappy.

RESULTS

The mean Walch and Duplay score at last follow-up was 84.3 (range 35-100). The final result for these patients was excellent in 14 patients (53.8 %), good in seven cases (26.9 %), poor in three patients (11.5 %) and bad in two patients (7.7 %). The mean Rowe score was 82.6 (range 35-100). Thirty-nine patients (86.7 %) were subjectively very satisfied or satisfied, and six (13.3 %) were unhappy. Four patients (8.9 %) had a recurrence of frank dislocation with a mean delay of 34 months (range 12-72 months). Three of them had a Hill-Sachs lesion preoperatively. Two patients had a preoperative ISIS at 4 points and two patients at 3 points.

CONCLUSION

The selection based on the ISIS allows a low rate of failure after an average term of 5 years. Lowering the limit for indication to 3 points allows to avoid the association between two major risk factors for recurrence, which are valued at 2 points. The existence of a Hill-Sachs lesion is a stronger indicator for the outcome of instability repair.

LEVEL OF EVIDENCE

Level IV, Retrospective Case Series, Treatment Study.

Outcomes of arthroscopic anterior shoulder instability in the beach chair versus lateral decubitus position: a systematic review and meta-regression analysis

PURPOSE

This study aimed to systematically review the clinical outcomes and recurrence rates after arthroscopic anterior shoulder stabilization in the beach chair (BC) and lateral decubitus (LD) positions.

METHODS

The authors performed a systematic review of multiple medical databases using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. All English-language literature from 1990 to 2013 reporting clinical outcomes after arthroscopic anterior shoulder stabilization with suture anchors or tacks with a minimum 2-year follow-up period were reviewed by 2 independent reviewers. Data on recurrent instability rate, return to activity/sport, range of motion, and subjective outcome measures were collected. Study methodological quality was evaluated with the Modified Coleman Methodology Score (MCMS) and the Quality Appraisal Tool (QAT). To quantify the structured review of observational data, meta-analytic statistical methods were used.

RESULTS

Sixty-four studies (38 BC position, 26 LD position) met inclusion criteria. A total of 3,668 shoulders were included, with 2,211 of patients in the BC position (average age, 26.7 ± 3.8 years; 84.5% male sex) and 1,457 patients in the LD position (average age, 26.0 ± 3.0 years; 82.7% male sex). The average follow-up was 49.8 ± 29.5 months in the BC group compared with 38.7 ± 23.3 months in the LD group. Average overall recurrent instability rates were 14.65 ± 8.4% in the BC group (range, 0% to 38%) compared with 8.5% ± 7.1% in the LD group (range, 0% to 30%; P = .002). The average postoperative loss in external rotation motion (in abduction) was reported in 19 studies in the BC group and in13 studies in the LD group, with an average loss of 2.4° ± 1.0° and 3.6° ± 2.6° in each group, respectively (P > .05).

CONCLUSIONS

Excellent clinical outcomes with low recurrence rates can be obtained after arthroscopic anterior shoulder stabilization in either the BC or the LD position; however, lower recurrence rates are noted in the LD position. Additional long-term randomized clinical trials comparing these positions are needed to better understand the potential advantages and disadvantages of each position.

LEVEL OF EVIDENCE

Level IV, systematic review of studies with Level I through Level IV evidence.

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.

Bone Anchors—A Preliminary Finite Element Study of Some Factors Affecting Pullout

Bone anchors (or suture anchors) are used to provide attachment points for sutures to connect tissue such as tendons or ligaments to bone, and work by engaging a threaded portion—sometimes tapered—to the cancellous and/or cortical bone. Such repair is often needed after trauma, or as part of reconstructive surgery. This paper uses the finite element method to compare the pullout characteristics of one common type of bone anchor in different cancellous bone structures. Finite element models are created by using computed tomography (CT) scans of cancellous bone and building computer-aided design (CAD) models to define the cancellous bone geometry. Orthopedic surgeons will sometimes remove parts of the cortical shell and this paper also examines the mechanical effects of decortication. Furthermore, the importance of the connection between anchor and cortical layer is examined. One of the key outcomes from the model is that the coefficient of friction between bone and anchor determines potential mechanisms of pullout. The stiffness of anchors and the effect of the cortical layer are presented for different pullout angles to obtain the theoretical response. The results show the detailed modeling that includes the micro-architecture of the cancellous bone is necessary to capture the large variations that can exist.

Fewer anchors achieves successful arthroscopic shoulder stabilization surgery: 114 patients with 4 years of follow-up

BACKGROUND

The shoulder is the most frequently dislocated joint, with an incidence of 10 to 20 per 100,000 each year. The optimum number of anchors to use in arthroscopic stabilization is a topic of growing interest; most surgeons use 3. Our stabilization technique is to commonly use only a single suture anchor to purse-string the capsulolabral tissue up and toward the glenoid. This study aimed to ascertain whether successful stabilization can be achieved with fewer than 3 anchors.

METHODS

Our study comprised 114 consecutive patients with anterior instability and a Bankart lesion undergoing arthroscopic stabilization with 4 years of follow-up. Outcome was measured by Oxford Instability Score (OIS) and recurrence of instability or dislocation. Patient demographics were 86.8% male, 13.2% female, mean age of 31 years, 76.3% Hill-Sachs lesions, 13.2% bony Bankart lesions, 13.2% glenoid defects, and 9.6% SLAP lesions. The majority of patients, 71 patients (62.3%), received only 1 anchor; 40 patients (35.1%) received 2 anchors, and 3 patients (2.6%) had 3 anchors.

RESULTS

The mean OIS was 44.3 preoperatively and 17.3 postoperatively (P < .0001). There was no difference in OIS improvement between the patients who received a single anchor and those who received 2 or 3 anchors (P > .05). Even with minor bony Bankart lesions and glenoid defects, a single suture anchor can be sufficient. Our failure rate of 6.1% is comparable with that of other published series.

CONCLUSION

Successful shoulder stabilization can be achieved with fewer than 3 anchors, and a single anchor is usually sufficient.

Induction of bone ingrowth with a micropore bioabsorbable suture anchor in rotator cuff tear: an experimental study in a rabbit model

BACKGROUND

The bioabsorbable suture anchor is probably one of the most commonly used tools in arthroscopic shoulder operations. However, there is controversy about whether the bioabsorbable anchor is replaced by bone. The object of this study is to evaluate bone ingrowth into the micropore bioabsorbable suture anchor and the differences in the biomechanical properties of a micropore anchor and a nonpore anchor.

MATERIALS AND METHODS

A total of 16 microsized holes (diameter, 250 ± 50 μm; depth, 0.2 mm) were made on the bioabsorbable anchors with a microdrill. Twelve adult New Zealand White rabbits were randomly divided into two groups: group A (n = 6), the nonpore bioabsorbable suture anchor group, and group pA (n = 6), the micropore bioabsorbable suture anchor group. Microcomputed tomography was used at 4 and 8 weeks postoperatively to evaluate ingrowth by bone volume fraction (BVF), which was measured by calculating the ratio of the total volume of bone ingrowth to that of the region of interest. For pullout strength testing, 3 additional rabbits (6 limbs) were used for mechanical testing.

RESULTS

The mean BVF was higher in group pA (0.288 ± 0.054) than in group A (0.097 ± 0.006). The micropore anchor had a higher pullout strength (0.520 ± 0.294 N) than the nonpore anchor (0.275 ± 0.064 N).

CONCLUSION

Micropore bioabsorbable suture anchors induced bone ingrowth and showed higher pullout strength, despite processing.

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

BACKGROUND

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

PURPOSE

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

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

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

RESULTS

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

CONCLUSION

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

MRI graduation of osseous reaction and drill hole consolidation after arthroscopic Bankart repair with PLLA anchors and the clinical relevance

PURPOSE

Conventionally, radiography studies revealed prolonged glenoidal drill hole visibilities with an unclear influence to the clinical outcome after arthroscopic Bankart repair using Poly-Laevo-Lactic-Acid (PLLA) anchors. The primary aim of the present study was the separated assessment of drill hole consolidation (DHC) and the concomitant osseous reaction (OR) of the glenoidal bio-degradation process in new specific magnetic resonance grading systems. In accordance with the specific DHC and the OR graduation, the clinical relevance was the secondary focus.

METHODS

Twenty-eight patients with arthroscopic Bankart repair using knotless PLLA anchors were prospectively followed and analyzed using a clinical scoring system (3, 6, 15 and 32 months). The T2-weighted OR and T1-weighted DHC were assessed using specific magnetic resonance imaging grading protocols (15 and 32 months).

RESULTS

Longitudinal assessments revealed successive clinical status improvements over time (32 months: Rowe 95.7 ± 3.8; Walch-Duplay 93.8 ± 6.6; Constant 93.9 ± 4.5; ASES 93.8 ± 6.9; DASH 28.6 ± 7.2; NAS(pain) 1.1 ± 1.3; NAS(function) 1.3 ± 1.4). The initial OR level regressed over the 15-32 month period while the DHC showed significant drill hole reductions (P < 0.05). The inferior glenoid revealed a significantly increased bio-degradation capacity (P < 0.05) with drill hole enlargements in 14.3%. Neither the OR nor the drill hole enlargements influenced the clinical status. In no case were clinical or radiologic signs for a foreign body reaction.

CONCLUSION

Knotless bio-anchors provide secure glenoidal fixation for Bankart repair without any specific clinical or MR evidence of an inflammatory response. The clinical status remained unaffected by the bio-degradation process.

LEVEL OF EVIDENCE

IV.

Risk factors for recurrence after Bankart repair a systematic review

PURPOSE

Arthroscopic Bankart repair of anterior shoulder instability is a common practice in orthopedics. The aim of this study was to evaluate pre-operative risks factors associated with recurrent instability and to delineate possible indications for revision surgery.

METHODS

A systematic review was performed including the following keywords: arthroscopy, Bankart repair, anterior shoulder instability, recurrence of instability, suture anchors and treatment outcome. Studies eligible for inclusion in the review were clinical trials published in the last 10 years investigating patients with anterior shoulder instability managed by an arthroscopic repair technique with suture anchors. The studies had to report data about recurrence of instability and investigational parameters (risk factors) that influenced the results referred to the rate of recurrence. Twenty-four articles were identified that met the inclusion criteria and underwent further review. Data from these studies were collected, and the risk of treatment failure was statistically recalculated. An estimate of the overall recurrence rate was obtained by pooling data about failure from the trials.

RESULTS

The rate of recurrent instability at 10 years of follow-up ranged from 3.4 to 35 %. Epidemiological parameters significantly associated with the recurrence of instability were age below 22 years old, male gender, the number of preoperative dislocations and participation in competitive sports. Surgical parameters significantly associated with recurrence of instability were repair with fewer than three anchors and the use of knotless anchors. The patho-anatomical factors significantly associated with recurrences were substantial associated glenoid or humeral head bone loss and the presence of anterior labroligamentous periosteal sleeve avulsion.

CONCLUSIONS

Knowledge of risk factors for post-operative outcomes allows surgeons to provide appropriate preoperative counselling to patients and support more realistic expectations. An accurate analysis of causes of failure should enable the correct revision strategy to be adopted.

LEVEL OF EVIDENCE

II.

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.

Treatment of Bankart lesions in traumatic anterior instability of the shoulder: a randomized controlled trial comparing arthroscopy and open techniques

PURPOSE

The objective of this study was to compare the functional assessments of arthroscopy and open repair for treating Bankart lesion in traumatic anterior shoulder instability.

METHODS

Fifty adult patients, aged less than 40 years, with traumatic anterior shoulder instability and the presence of an isolated Bankart lesion confirmed by diagnostic arthroscopy were included in the study. They were randomly assigned to receive open or arthroscopic treatment of an isolated Bankart lesion. In all cases of both groups, the lesion was repaired with metallic suture anchors. The primary outcomes included the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire.

RESULTS

After a mean follow-up period of 37.5 months, 42 patients were evaluated. On the DASH scale, there was a statistically significant difference favorable to the patients treated with the arthroscopic technique, but without clinical relevance. There was no difference in the assessments by University of California, Los Angeles and Rowe scales. There was no statistically significant difference regarding complications and failures, as well as range of motion, for the 2 techniques.

CONCLUSIONS

On the basis of this study, the open and arthroscopic techniques were effective in the treatment of traumatic anterior shoulder instability. The arthroscopic technique showed a lower index of functional limitation of the upper limb, as assessed by the DASH questionnaire; this, however, was not clinically relevant.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL RELEVANCE

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

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.