The Clinical and Biomechanical Performance of All-Suture Anchors: A Systematic Review

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.

Non-absorbable Suture-Loaded Anchors for Finger Pulley Reconstruction

A 59-year-old woman, who previously underwent surgery on her left long finger A1 pulley and left small finger distal interphalangeal joint for triggering and mallet deformity at another medical facility in March 2021, sought evaluation at an Orthopedics Hand clinic. She presented with limited finger movement, a flexion contracture, and difficulty extending her left long finger. Examination revealed an A2 pulley injury with extensive scar tissue. Subsequently, she underwent surgery to remove the scar tissue and reconstruct the A2 pulley using suture tape anchors. This case highlights the negative outcome following A1 pulley release due to an unintended A2 injury, resulting in significant scarring and an intrinsic plus digit posture. Additionally, it underscores the potential effectiveness of using non-absorbable synthetic sutures to minimize scarring and promote an early range of motion in cases where healing leads to excessive scarring around the flexor tendon sheath.

Two-Portal Arthroscopic Knotless All-Suture Anchor Posterior Labral Repair

Isolated posterior shoulder instability accounts for approximately 10% of shoulder instability cases. Patients may present after an acute trauma or with insidious onset and associated posterior shoulder pain. Knotless and all-suture anchor devices have become increasing popular and are often used in arthroscopic shoulder instability cases to avoid knot stacks and allow for the ability to re-tension the fixation. This technical note describes our technique for 2-portal posterior labral repair using knotless all-suture anchors with the patient in the lateral decubitus position.

Pain scores and functional outcomes of patients with shoulder labral repair using all-suture anchors versus conventional anchors

HYPOTHESIS/PURPOSE

The purpose of this study was to compare PROMs in patients undergoing anterior glenoid labral repair using all-suture versus conventional anchors. We hypothesized PROMs would be similar between groups.

METHODS

We performed a retrospective review of the Arthrex Global Surgical Outcomes System (SOS) database, querying patients who underwent arthroscopic glenoid labral repair between 01/01/2015 and 12/31/2020. Patients aged 18-100, who had isolated glenoid labrum repair with at least 12-month follow-up were included. The visual analog pain scale (VAS), Western Ontario Shoulder Instability Index, Veteran's RAND 12-items health survey, single assessment numeric evaluation and the American Shoulder and Elbow Surgeons score (ASES) were compared preoperatively, 3 months, 6 months, 1 year and 2 years postoperatively in patients who received all-suture anchors versus conventional anchors in the setting of anterior glenoid labrum repair. Our primary aim was comparison of PROMs between patients receiving all-suture versus conventional suture anchors. Secondarily, a sub-analysis was performed comparing outcomes based on anchor utilization for patients with noted anterior instability.

RESULTS

We evaluated 566 patients, 54 patients receiving all-suture anchors and 512 patients receiving conventional anchors. At two-year follow-up there was no significant difference between the two groups in PROMs. In a sub-analysis of isolated anterior labrum repair, there was an improvement in ASES (P = 0.034) and VAS (P = 0.039) with the all-suture anchor at two-year follow-up.

CONCLUSIONS

All-suture anchors provide similar or superior pain and functional outcome scores up to 2 years postoperatively compared to conventional anchors.

CLINICAL RELEVANCE

As all-suture anchors gain popularity among surgeons, this is the largest scale study to date validating their use in the setting of glenoid labrum repair. Institutional Review Board (IRB): IRB202102550.

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

PURPOSE

To evaluate the safety and efficacy of a next-generation, all-suture anchor in patients undergoing arthroscopic repair of rotator cuff tears, compared with that of an established solid suture anchor.

METHODS

Between April 2019 and January 2021, a prospective, comparative, randomized controlled noninferiority study conducted on people with Chinese ethnicity at 3 tertiary hospitals enrolled patients (18-75 years) requiring arthroscopic treatment for rotator cuff tears. Patients were randomized into 2 cohorts receiving either all-suture anchor or solid suture anchor and followed for 12 months. The primary outcome was the Constant-Murley score at the 12-month follow-up. Magnetic resonance imaging assessments determined the rate of retear of rotator cuff repair (defined as Sugaya classification 4 and 5). Safety evaluation was performed at all follow-up points to determine the adverse events (AEs).

RESULTS

In total, 120 patients with rotator cuff tears (mean age, 58.3 years; 62.5% female; 60 receiving all-suture anchor) underwent treatment. Five patients were lost to follow-up. Both cohorts showed significant improvement in Constant-Murley scores between baseline and 6 months (P < .001) and between 6 and 12 months (P < .001). There were no significant differences in Constant-Murley scores between the 2 cohorts at 12 months (P = .122) after operation. The retear rate at 12 months was 5.7% and 1.9% in the all-suture and solid suture anchor cohorts, respectively (P = .618). There were 2 cases of intraoperative anchor pullout, both of which were successfully resolved. No cases of postoperative reoperation or other anchor-related AEs were reported.

CONCLUSIONS

The all-suture anchor offered equivalent clinical performance to an established solid suture anchor at the 12-month follow-up in patients undergoing arthroscopic repair of rotator cuff tears. The retear rate was not statistically significantly different between the 2 cohorts.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

An additively manufactured titanium tilting suture anchor: a biomechanical assessment on human and ovine bone specimens

Introduction

A novel titanium tilting suture anchor was designed and fabricated using additive manufacturing. The anchor enjoyed a nonsymmetrical structure to facilitate its insertion procedure through a weight-induced tilt, a saw-teeth penetrating edge to provide a strong initial fixation into cancellous bones of various densities, and an appropriate surface texture to enhance the longterm fixation strength through bone ingrowth.

Methods

Biomechanical tests were performed on 10 ovine and 10 human cadaveric humeri to examine the insertion procedure and assess the initial fixation strength of the anchor, in comparison with a standard screw-type anchor as control.

Results

This study indicated a simple yet reliable insertion procedure for the tilting anchor. All anchors survived after 400 cycles of cyclic loadings and failed in the load-to-failure step. There were no significant differences between the displacements and fixation stiffnesses of the anchors in either group. The ultimate failure load was significantly smaller (p<0.05) for tilting anchors in ovine group (273.7 ± 129.72 N vs. 375.6 ± 106.36 N), but not different in human group (311.8 ± 82.55 N vs. 281.9 ± 88.35). Also, a larger number of tilting anchors were pulled out in ovine group (6 vs. 3) but a smaller number in human group (4 vs. 6).

Conclusion

It was concluded that the biomechanical performance of the designed tilting anchor is comparable with that of the standard screw-type anchors.

UHMWPE suture induced pseudotumor following arthroscopic rotator cuff repair: A case report

UHMWPE suture shows excellent biocompatibility and complication associated with suture debris had not been described before in shoulder surgery. In this study, a case of a 38-year-old man with a wear debris pseudotumor mimicking osteochondromatosis in the subacromial bursa five years after arthroscopic rotator cuff repair using a composite braid suture (a polydioxanone core with a sleeve of UHMWPE) was presented. Histological examination confirmed the presence of suture fragments surrounded with the osteochondral layer without inflammatory reactions. The present study implies the potential risk of free fragmented remnants from the UHMWPE suture. Because of the silent nature of the histological response, a high index of suspicion should be necessary to disclose the chanciness of its use.

Clinical and radiological outcome of all-suture anchors in shoulder and elbow surgery

Background

All-suture anchors (ASAs) are noted to cause various bone reactions when used in upper limb surgery but clinical implications are unknown.

Methods

88 shoulders and 151 elbows with a mean follow-up of 47.1 ± 17.7 months were invited for follow-up including clinical examination, questionnaires and radiographs. The anchor drill holes were radiographically assessed.

Results

At final follow up, mean DASH was 12.9 ± 13.8 and mean VAS 2.2 ± 2.4 in the shoulder population. In the elbow group mean MEPS was 91.8 ± 12.7 and mean VAS 1.5 ± 1.9. Implant-specific complications were seen in 10 elbow cases but none in the shoulder group. The mean diameter of the 1.4 mm all-suture anchor drill hole was enlarged to 2.5 ± 1.4 mm in the shoulder group and to 2.9 ± 1.0 mm in the elbow group. 50% of the 1.4 mm anchor drill holes showed abnormal morphology but these morphologic changes did not correlate with clinical outcome, complications or reoperation rate.

Discussion

Satisfying clinical outcomes are found in upper limb surgery using ASAs. Various bone changes are seen after implantation of an ASA, but these are not clinically relevant. Long-term consecutive follow-up data is required.

Comparison of medial tibiofemoral joint mechanics between all-suture anchors and transtibial pullout technique for posterior medial meniscal root tears

BACKGROUND

The posterior medial meniscal root tear (PMMRT) seriously impacts the tibiofemoral joint biomechanics. Two available techniques for PMMRT repair include the transtibial pullout (TPO) repair and all-suture anchor (ASA) repair techniques. These techniques have not been compared biomechanically.

METHODS

A total of 20 fresh porcine cadaveric knee specimens were used. All 20 knees were randomly and evenly distributed into four groups (five specimens per group): (1) intact posterior meniscal root, (2) PMMRT, (3) TPO repair technique for PMMRT, and (4) ASA repair technique for PMMRT. The tibiofemoral contact mechanics were investigated using a pressure sensor. All knee specimens were tested by being loaded with 600 N axial compressive force at three different flexion angles (0°, 45°, and 90°). The contact surface area, contact pressure, peak pressure, and time-zero displacement were recorded.

RESULTS

The PMMRT caused a significant decrease in contact surface area, an increase in contact pressure, and peak pressure from the reference values observed in the intact meniscus group (P = 0.05, 0.016, and 0.008, respectively). After fixation, no significant difference was observed between the ASA and intact group. Meanwhile, significant differences were found between the TPO and intact group in terms of contact surface area, contact pressure, and peak pressure. In the comparison between the two techniques, the ASA group demonstrated higher contact surface area than the TPO group at the average knee flexion angle (p = 0.05).

CONCLUSION

For most testing conditions, the ASA technique demonstrated superior biomechanical property in terms of contact surface area compared with the TPO technique under compressive loading conditions. The ASA technique could also restore the tibiofemoral contact mechanics to be comparable with those of the native intact knee. Meanwhile, a significant difference in tibiofemoral mechanics, compared with the intact knee, could be observed in the TPO technique.

"Make and Use" All Suture Anchor-A Cost-Effective Method of Making an All-Suture Anchor

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

Posterior Labral Repair Using Knotless "All-Suture" Suture Anchors

Isolated posterior instability is well described but relatively uncommon, accounting for less than 10% of all shoulder instability cases. When nonoperative management fails, surgical outcomes demonstrate improved patient-reported outcomes with a high level of return to sport. Knotless suture anchor and "all-suture" suture anchor technology are now available and used for instability procedures in the shoulder. This technical description describes knotless "all-suture" suture anchor fixation for isolated posterior labral tears.

Chronic Lateral Ankle Instability with Os Subfibulare in a Child Treated with Modified Broström/Gould Surgical Technique - A Case Report

Introduction

Patients with lateral instability of the ankle have a much higher prevalence of an os subfibulare compared with the general population. In children and adolescents with known os subfibulare and chronic instability of the ankle, surgical resection of the os subfibulare and the Broström/Gould procedure to reattach the ATFL to the fibula has been described if conservative therapy fails.

Case Report

Our case is about a 10-year-old girl with chronic instability of the ankle and a symptomatic os subfibulare, with additional cystic and edematous changes in the distal fibula in the MRI. Due to the reduced bone density, we assumed a higher risk of anchor pullout with the normal refixation at the distal fibula. Therefore, the surgical technique according to Broström/Gould was modified and the ATFL was refixed on the talar side.

Conclusion

In cases of symptomatic os subfibulare with clinical instability of the ankle, a Broström/Gould operation and resection of the os subfibulare is recommended after failure of conservative therapy. Our case showed that a very satisfying post-operative result can be achieved with a modification of the Broström/Gould operation, with reattachment of the ATFL to the talus instead of the fibula.

Tibialis anterior tendon transfer using suture anchor provides excellent alternative treatment for relapse clubfoot: A case report

INTRODUCTION

Relapsed clubfoot is defined as the recurrence of any component of deformity after a complete correction. While the Ponseti method has been known to have excellent outcomes, several relapse cases have been reported. Thus, further surgical intervention is needed to achieve a good and reliable long-term outcome.

PRESENTATION OF THE CASE

We report a presentation of a 5-year-old boy who came to the clinic with a relapsed bilateral clubfoot after serial Ponseti casting. Plantar fascia release, Achilles tendon lengthening, and tibialis anterior tendon transfer (TATT) were performed respectively followed by an above-knee cast. The patient gained acceptable walking balance and ability to perform high impact sports at one year follow-up.

CLINICAL DISCUSSION

There are several factors contributing to the relapse clubfoot including adherence to post op foot abduction brace (FAB) protocol, muscle imbalance or inadequate correction of initial deformities. The current case report described a relapse clubfoot following serial Ponseti casting caused by non-compliance of the use of foot abduction brace. Further surgical interventions must be performed in the presence of relapse case of clubfoot.

CONCLUSION

Relapse clubfoot is the presence of any recurring deformity following correction. Surgical intervention, especially TATT procedure provides a favorable outcome in treating patients with relapse clubfoot.

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.

Soft Anchors for Rotator Cuff Repair: A Review

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All-suture anchors or so-called "soft" anchors, initially adapted for labral repairs, have increased in popularity for use in rotator cuff repair because of their smaller size, decreased occupation of the footprint, improved points of fixation, ease of use, and ease of revision.

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In limited series, soft anchors have demonstrated equivalent biomechanical and clinical performance compared with hard body anchors for rotator cuff repair.

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Perianchor cyst formation can occur with both hard body and soft anchors.

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Biomechanical and clinical data support aiming for vertical angles of insertion for soft anchors.

Effect of Anchor Density on Functional Outcomes After Arthroscopic Hip Labral Repair

BACKGROUND

While labral repair has been widely adopted as the first line treatment for labral injury during hip arthroscopy, there is no widespread consensus on the procedural technique, including the number of anchors that should be used to avoid recurrent instability and revision surgery.

PURPOSE

To determine if anchor density can predict patient-reported outcomes after arthroscopic labral repair in the hip.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients aged 18 to 50 years who underwent primary hip arthroscopic surgery with labral repair between January 2011 and December 2016 were identified from a prospectively collected database. Exclusion criteria consisted of previous ipsilateral surgery, osteoarthritis (Tönnis grade >1), and severe cartilage defects (Outerbridge grade III/IV) or concomitant labral reconstruction, capsular reconstruction, or microfracture. Minimum 2-year patient-reported outcomes (modified Harris Hip Score [mHHS], Hip Outcome Score [HOS]-Activities of Daily Living [ADL], HOS-Sport Specific Subscale [SSS], 12-Item Short Form Health Survey [SF-12]), rates of achieving the minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) for each score, revision surgery rate, and rate of conversion to total hip arthroplasty (THA) were compared based on anchor density (number of anchors per millimeter of labral tear).

RESULTS

A total of 634 hips (575 patients) with a mean age of 30.4 ± 9.5 years (range, 18.0-49.9 years) met inclusion criteria. The mean labral tear size was 31 ± 11 mm (range, 2-70 mm) with a median number of anchors used for labral repair of 3 (range, 1-7) and mean anchor density of 0.11 ± 0.08 anchors (range, 0.03-1.33) per millimeter of labral tear. Hips with a minimum 2-year follow-up (451/634 [71.1%]) had significant improvements on the mHHS, HOS-ADL, HOS-SSS, and SF-12 Physical Component Summary (P < .001 for all). There was no significant correlation detected between anchor density or number of anchors used and postoperative scores (correlation coefficient range, -0.05 to 0.17; P > .05 for all). The rate of revision surgery was 6.4% (28 patients), with 8 hips found to have labral tears and/or deficiency on revision. Additionally, 6 hips (1.3%) had to undergo THA at a mean of 3.6 ± 2.1 years (range, 2.0-5.5 years).

CONCLUSION

Anchor density did not have a correlation with postoperative outcomes, achieving the MCID or PASS, revision hip arthroscopic surgery, complications, or conversion to THA.

Three Medial All Suture Anchors Improves Contact Force Compared to Two Hard Body Anchors in a Biomechanical Two-Tendon Rotator Cuff Tear Model

Purpose

To biomechanically compare a knotless double-row construct with 3 medial all-suture (3AS) anchors with a standard 2 medial hard body (2HB) anchor construct.

Methods

Twelve matched cadaveric shoulder specimens with a mean age of 57 years (range: 54-61 years) were randomized to receive a knotless double-row repair with either a 3AS or 2HB construct. In the 3AS construct, three 2.6-mm all-suture anchors were placed adjacent to the articular margin and secured laterally with two 4.75-mm knotless hard body anchors. In the 2HB construct, two 4.75-mm medial hard body anchors were placed medially, lateral fixation was identical to the 3AS construct. Creep, displacement, stiffness, and ultimate load were recorded for each sample. In addition, a SynDaver model was used to compare contact pressure between the 2 repair constructs.

Results

There were no differences in cyclic displacement at 1, 30, and 100 cycles (P = .616, .497, .190, respectively), cyclic stiffness (.928), ultimate load (.445), or load to failure (P = .445) between the 2 constructs. The 3AS repair construct had improved contact pressure between tendon and bone when compared with the 2HB construct at loads of 20 N, 30 N, and 40 N (P = .01, .02, and .04, respectively).

Conclusions

Displacement and load to failure properties are similar between knotless constructs using either 2HB or 3AS for the medial row. However, contact force may improve with the use of 3 medial all-suture anchors.

Clinical Relevance

As all-suture anchors are smaller in size when compared with hard body anchors. For this reason, there is potential to place an additional all-suture medial anchor to improve contact force and potentially improve rotator cuff healing when compared with the use of hard body anchors.

Interference Screws Are Biomechanically Superior to Suture Anchors for Medial Patellofemoral Ligament Reconstruction: A Systematic Review and Meta-Analysis

Purpose

To systematically review the literature to evaluate the biomechanical properties of the interference screw (IS) versus suture anchor (SA) techniques for patellar and femoral fixation of medial patellofemoral ligament (MPFL) reconstruction.

Methods

A systematic review was performed by searching PubMed, the Cochrane library, and Embase using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify studies that analyzed the biomechanical properties of IS and SA techniques for MPFL reconstruction. The search phrase implemented was “medial patellofemoral ligament reconstruction biomechanics.” Evaluated outcomes included ultimate load to failure (N), stiffness (N/mm), and mode of failure. Forest plots were created for statistical analysis and heterogeneity was assessed via I² statistic.

Results

Six studies met inclusion criteria, including a total of 108 cadaveric specimens, for MPFL patellar fixation, and 3 studies met inclusion criteria, including a total of 50 cadaveric specimens, for MPFL femoral fixation. Pooled analysis from 5 studies reporting on stiffness for MPFL patellar fixation revealed a statistically significant difference in favor of IS compared with SA (P = .007). Pooled analysis from 3 studies reporting on ultimate load to failure of femoral fixation revealed a statistically significant difference in favor of IS compared with SA (P = .043).

Conclusions

The use of IS was associated with a greater stiffness compared with the use of SA in MPFL patellar fixation, but there was no difference in load to failure between IS and SA. The use of IS was associated with a greater load to failure compared with the use of SA in MPFL femoral fixation, but there was no difference in stiffness between IS and SA.

Clinical Relevance

There have been multiple individual biomechanical studies conducted comparing IS and SA fixation for MPFL patellar and femoral fixation; however, they have yielded conflicting results, with small sample sizes. Pooling the data from these studies in a meta-analysis may allow for more meaningful biomechanical data to coincide with the existing, albeit scarce, clinical data, this may help to inform clinical decision making for surgeons managing these injuries.

Case Report: Bilateral Biportal Endoscopic Open-Door Laminoplasty With the Use of Suture Anchors: A Technical Report and Literature Review

Background

Unilateral biportal endoscopy (UBE) is a newly developed technique for spine surgery. Owing to the convenience of nerve decompression and compatibility with open surgical instruments under endoscopic guidance, this technique has seen widespread global use. In this study, we first used modified UBE with suture anchor fixation for cervical laminoplasty in a 65-year-old female patient with good clinical outcomes.

Methods

We used bilateral biportal endoscopy (BBE) for cervical laminoplasty with suture anchor fixation in a patient with cervical stenosis. Under endoscopic guidance, a bilateral approach was used to make the gutter and lift the lamina door. After the lamina doors were opened, sutures were tied tightly using facia cannula and knot pusher. After confirming the solidarity of the open-door status, the drainage tube was inserted and the incisions were closed. The patient’s pre- and postoperative radiological and clinical results were evaluated.

Results

Postoperative Japanese Orthopaedic Association (JOA) and Neck Disability Index (NDI) scores were improved clinically, and cervical canal was decompressed radiologically.

Conclusions

BBE laminoplasty combined with suture anchor fixation showed a favorable clinical and radiological result and appears to be a safe and effective technique for cervical stenosis.

Perianchor Cyst Formation Is Similar Between All-Suture and Conventional Suture Anchors Used for Arthroscopic Rotator Cuff Repair in the Same Shoulder

Purpose

The purpose of this study was to compare perianchor cyst formation between soft and hard suture anchors placed in the same patient 1 year after arthroscopic rotator cuff repair (ARCR).

Methods

This study reviewed patients who underwent primary ARCR using a “hybrid” technique using at least one soft anchor (FiberTak, Arthrex, Naples, FL) and one hard anchor (SwiveLock) placed in the same shoulder between January 1, 2018 and December 31, 2018. Magnetic resonance imaging was obtained at minimum 1-year postoperative to assess cyst formation (perianchor fluid signal) and rotator cuff healing. Range of motion (ROM) and patient-reported outcome measures (PROMs) were evaluated at baseline and 1-year follow up. PROMs included visual analog scale pain score, Simple Shoulder Test score, American Shoulder and Elbow Surgeon (ASES) score.

Results

Nineteen patients with a combined 45 hard and 26 soft suture anchors were available for follow-up at a mean of 20 months postoperatively. There was a higher proportion of grade 1 fluid signal changes in the hard anchor group compared to the soft group (62.2% to 7.7; P < .001); however, there was no difference in the incidence of cyst formation (grade 2 or 3 changes) between groups (13.3% vs 3.8%; P = .251). There was also no difference in the rate of cyst formation between biocomposite and polyether-ether-ketone-type hard anchors (18.2% vs 0%; P = .113) or between anchors placed at the greater and lesser tuberosities (10.2% vs 5.3%, P = .519).

Conclusion

Hard suture anchors showed increased fluid signal compared to soft suture anchors at short-term follow-up after ARCR, but there was no difference in cyst formation between anchor types.

Surgical Repair of Posttraumatic Hallux Valgus Deformity in a Collegiate Football Player: A Case Report

CASE

We report a rare case of posttraumatic hallux valgus in a collegiate football player after an acute medial collateral ligament tear of the first metatarsophalangeal joint. The patient was treated with a modification of the modified McBride technique, using an all-suture anchor for the medial ligamentous complex repair. There was return to sport at 5 months and a Foot and Ankle Outcome Score of 95% at 10 months.

CONCLUSION

A modified McBride procedure further modified with the utilization of an all-suture anchor for the medial ligamentous complex repair can result in correction of deformity, pain-free movement and return to sport.

Post-Traumatic Hallux Valgus: A Modified Surgical Technique

Post-traumatic hallux valgus, a turf toe variant, is a rare, yet limiting injury. According to the literature, the deformity has been associated with acute medial collateral ligament tears, turf toe variant injuries, Lisfranc injury patterns, and first metatarsal fractures. There have been few documented cases of post-traumatic hallux valgus secondary to medial collateral ligament tears, and the treatment has been variable. Some authors have described direct end-to-end repair of the ligament to address the deformity, while others have described a modified McBride bunionectomy involving a Silver bunionectomy, lateral soft tissue release, and medial capsular and ligamentous repair. We propose a modified technique similar to the modified McBride bunionectomy, however, with the use of an all-suture anchor in the medial capsular and ligamentous repair. Our belief is that the all-suture anchor will allow for a stronger repair that will meet the physical demands of everyday ambulation and athletic participation. We used this technique in an individual who had evidence of a medial ligamentous complex injury of the hallux on MRI and failed conservative management. Postoperatively, the patient is immobilized until they can begin working on range of motion, strengthening, and finally to achieve return to full activity and sports.

Effect of difference in fixation methods of tendon graft and the microfracture procedure on tendon-bone junction healing

Background

There are generally two methods of fixation for tendon grafts used in ligament reconstruction: bone tunnel fixation and anchor fixation. The microfracture (Mf) procedure is a technique to induce bleeding from the bone marrow, and the bleeding may contain cells with differentiation potential. However, few studies have compared the effects of the Mf procedure with those of the fixation methods. This study aimed to evaluate the effectiveness of the Mf procedure on two tendon graft fixation methods: histological, gene expression, tendon graft thickness, and mechanical. We especially focused our investigation on junction healing of tendon grafts and bone in the two fixation methods.

Methods

We used 20 rabbits to evaluate tendon and bone healing in a peroneal tendon graft model. The rabbit models were divided into five groups according to the combination of peroneal tendon graft fixation method and Mf technique as follows: control group (C, n = 4), bone tunnel fixation without Mf procedure group (BT − Mf, n = 4), bone tunnel fixation with Mf procedure group (BT + Mf, n = 4), anchor fixation without Mf procedure group (A − Mf, n = 4), and anchor fixation with Mf procedure group (A + Mf, n = 4). All animals were sacrificed at 4 weeks postoperatively. The specimens underwent histological evaluation, mRNA analysis, tendon graft thickness at the tendon-bone junction, and biomechanical testing.

Results

Histological evaluation of the BT + Mf and A + Mf groups showed healing with fibrocartilage formation at the tendon graft-bone junction. The mRNA expression showed significant increase in type 2 collagen, Scleraxis, and SRY-box9 in the BT + Mf and A + Mf groups. In biomechanical tests, the BT + Mf and A + Mf groups showed significantly increased tensile strength compared with the BT − Mf and A − Mf groups (BT + Mf group, 21.6 ± 1.7 N; A + Mf group, 22.5 ± 2.3 N vs. BT − Mf group, 12.3 ± 2.4 N; A − Mf group, 11 ± 2.3 N).

Conclusion

The Mf procedure resulted in fibrocartilage formation at the tendon-bone junction in the BT and anchor fixation and improved the fixation strength at 4 weeks.

Increased Load to Failure in Biceps Tenodesis With All-Suture Suture Anchor Compared With Interference Screw: A Cadaveric Biomechanical Study

PURPOSE

To compare the biomechanical characteristics of a single radially expanding all-suture anchor with an interference screw for open subpectoral long head of biceps tendon (LHBT) tenodesis.

METHODS

Eighteen fresh-frozen matched-pair human cadaveric humeri were used for this biomechanical study. The matched pair humeri were randomly assigned into 2 experimental biceps tenodesis groups: conventional interference screw (CIS) or all-suture suture anchor (ASSA). Open subpectoral LHBT tenodesis was then performed and biomechanical testing was performed using a servohydraulic test frame. A preload of 5 N was applied for 2 minutes before cyclic loading. Displacement was recorded at cycle 300 (D300) and cycle 500 (D500) and at ultimate failure. Data recorded included displacement, load to failure, displacement at failure. Paired t test was used for analysis.

RESULTS

Decreased displacement was observed for the CIS group at D300 (1.67 ± 0.57 mm vs 3.35 ± 2.24 mm; P = .04), D500 (2.00 ± 0.76 mm vs 3.87 ± 2.20 mm; P = .04), and at failure (5.17 ± 3.05 mm vs 10.76 ± 2.66 mm; P < .001). Load to failure was lower in CIS specimens (170 ± 24.5 N vs 217.8 ± 51.54 N; P = .02). Failure in each case was tendon pullout for all CIS specimens; in ASSA 6 specimens failed as the suture pulled through the tendon, 2 specimens failed by suture breakage. No difference in stiffness was observed between the 2 groups (CIS = 98.33 ± 22.98 N/m vs ASSA = 75.94 ± 44.83 N/m; P = .20).

CONCLUSIONS

Our study found that open subpectoral biceps tenodesis performed with an ASSA construct results in increased load to failure as compared with CIS. However, the CIS did demonstrate decreased displacement as compared to ASSA in this cadaveric biomechanical study.

CLINICAL RELEVANCE

ASSA and CIS at time zero provide fixation as indicated by the provider intraoperatively for LHBT tenodesis. ASSA, however, does remove less cortical bone than does CIS and therefore produces a smaller stress riser in the proximal humerus. Further testing as to the integrity of ASSA is warranted to determine the integrity of the tenodesis with cyclical loading.

Editorial Commentary: All-Suture Anchors Are Small, Easier to Revise, and Biomechanically Equivalent to Conventional Implants: They Are the Way of the Future

All-suture anchors (ASAs) show biomechanical equivalence to conventional implants. The smaller size and easier ability to revise are important advantages of ASAs. A more vertical insertion angle increases ASA pullout strength. Proper depth of insertion is required to optimally seat ASAs on cortical bone. ASA pullout strength also results from compression of cancellous bone between the anchor and the cortex, and appropriately pretensioning the suture before loading is critical. A larger anchor (and a higher the number of sutures loaded per anchor) leads to a higher pullout strength of the anchor. Understanding the correct implantation technique is important to optimize the strength of ASAs.

Rotator cuff repair techniques: Current concepts

Arthroscopic rotator cuff repair is being performed by an ever-increasing number of surgeons. With an ageing population and growing patient expectations it is crucial that clinical outcomes are optimised. Anatomical reduction of the tendon back to its footprint with minimal tension contributes to this, but this can only be achieved if key biomechanical factors are taken into consideration. In this review of the technical aspects of a rotator cuff repair, we focus on: (1) patient positioning, (2) biomechanical principles, (3) optimal visualisation, and (4) repair techniques for both anterior and postero-superior tears.

The Effect of Torque Differences for All-Suture Anchor Fixation Strength: A Biomechanical Analysis

Purpose

To investigate the biomechanical influence of differential loading of suture strands (torque) on the fixation strength of knotted and knotless all-suture anchors.

Methods

The biomechanical strength of 48 all-suture anchors was evaluated for 4 conditions in polyurethane foam blocks: (1) 12 knotted all-suture anchors loaded proportionately, (2) 12 knotted all-suture anchors with 1 suture strand bearing 50% of total force (partial torque), (3) 12 knotted all-suture anchors with 1 strand fixated and the other loaded (full torque), and (4) 12 knotless all-suture anchors with the loop kept open via a fixed rod. Force for 1 mm and 2 mm of displacement and ultimate failure load were assessed.

Results

For 1 mm of displacement, groups 2, 3, and 4 showed significantly lower forces than group 1 (all P < .001), with no statistically significant difference between groups 2 and 3 (P = .516); for 2 mm of displacement, all groups showed significantly lower forces than group 1 (P < .001), which positively correlated with applied torque. No differences in the mean ultimate loads observed between testing groups 1, 2, and 4 were noted, with 93.3 ± 3.8 N, 91.4 ± 4.7 N, and 92.6 ± 5.6 N, respectively; however, group 3 exhibited a significantly lower mean ultimate load (62.3 ± 1.7 N) than all other groups (P < .001).

Conclusions

The ultimate failure load of knotted and knotless all-suture anchor fixation was partially affected by loading differentials between strands in this validated foam block model. Differential loading of knotted all-suture anchor fixation presented greater initial displacement when compared with symmetrically loaded knotted all-suture anchors. Despite an initial increase in displacement, knotless all-suture anchors showed similar ultimate failure loads to knotted all-suture anchors with strands loaded equally.

Clinical Relevance

The role of suture strand loading imbalance on anchor fixation is variable and should be considered during placement and fixation of the repair constructs in a clinical setting.