Anchored Transosseous-Equivalent Versus Anchorless Transosseous Rotator Cuff Repair: A Biomechanical Analysis in a Cadaveric Model

Arthroscopic transosseous anchorless rotator cuff repair reduces bone defects related to peri-implant cyst formation: a comparison with conventional suture anchors using propensity score matching

BACKGROUND

The transosseous anchorless repair (ToR) technique was recently introduced to avoid suture anchor-related problems. While favorable outcomes of the ToR technique have been reported, no previous studies on peri-implant cyst formation with the ToR technique exist. Therefore, this study compared the clinical outcomes and prevalence of peri-implant cyst formation between the ToR technique and the conventional transosseous equivalent technique using suture anchors (SA).

METHODS

Cases with arthroscopic rotator cuff repair (ARCR) between 2016 and 2018 treated with the double-row suture bridge technique were retrospectively reviewed. Patients were divided into ToR and SA groups. To compare clinical outcomes, 19 ToR and 57 SA cases without intraoperative implant failure were selected using propensity score matching (PSM). While intraoperative implant failure rate was analyzed before PSM, retear rate, peri-implant cyst formation rate, and functional outcomes were compared after PSM.

RESULTS

The intraoperative implant failure rate (ToR, 8% vs. SA, 15.3%) and retear rate (ToR, 5.3% vs. SA, 19.3%) did not differ between the two groups (all P>0.05). However, peri-implant cysts were not observed in the ToR group, while they were observed in 16.7% of the SA group (P=0.008). Postoperative functional outcomes were not significantly different between the two groups (all P>0.05).

CONCLUSIONS

The ToR technique produced comparable clinical outcomes to conventional techniques. Considering the prospect of potential additional surgeries, the absence of peri-implant cyst formation might be an advantage of ToR. Furthermore, ToR might reduce the medical costs related to suture anchors and, thereby, could be a useful option for ARCR. Level of evidence: III.

A comparison between knotted and knotless medial row of suture bridge technique in arthroscopic rotator cuff repair surgery: a meta-analysis

BACKGROUND

The shoulder arthroscopic suture bridge technique is currently very popular, but scientific evidence relating to the clinical outcomes of the medial row with or without knots has not been systematic reviewed.

PURPOSE

The purpose of this study was to compare the clinical outcomes of knotted versus knotless double-row suture bridges for rotator cuff repairs.

STUDY DESIGN

Meta-analysis.

METHOD

Five databases that contain literature in English were searched (Medline, PubMed, Embase, Web of Science, and the Cochrane Library), with a focus on works published between 2011 and 2022. Clinical data relating to arthroscopic rotator cuff repair with the suture bridge approach was examined and the outcomes of medial row knotting contrasted with that of the knotless technique. The search phrase used was: (double row) AND (rotator cuff) AND (repair), and the search method is subject term plus free word search. Literature quality evaluation was performed using the Cochrane "risk of bias" tool 1.0 and the Newcastle-Ottawa scale quality assessment instrument.

RESULTS

One randomized controlled trial, four prospective cohort studies, and five retrospective cohort studies were included in this meta-analysis. Data pertaining to 1146 patients was drawn from these ten original papers and analyzed. Meta-analyses that were performed on 11 postoperative outcomes revealed that none of the differences were statistically significant (P > 0.05) and that the publications were unbiased (P > 0.05). Postoperative retear rate and postoperative retear categorization were the outcomes assessed. Scores on postoperative pain, forward flexion, abduction, and external rotation mobility were collated and evaluated. The University of California, Los Angeles scoring systems in the first year following surgery, the American Shoulder and Elbow Surgeons score and Constant scales in the first and second years after surgery were the secondary outcomes spotlighted in this study.

CONCLUSION

The clinical outcomes of shoulder arthroscopic rotator cuff repair with the suture bridge technique with or without a knotted medial row was proven to be equivalent. These outcomes are about postoperative retear, postoperative retear classification, postoperative shoulder function score, postoperative shoulder mobility, and postoperative pain, respectively. It should be noted that the conclusions are based on short-term clinical follow-up data.

Arthroscopic Anchorless Transosseous Rotator Cuff Repair Produces Equivalent Clinical Outcomes and Imaging Results as a Standard Suture Bridge Technique with Anchors

Purpose

To compare the clinical and imaging outcome of arthroscopic transosseous (TO)-equivalent rotator cuff repair (RCR) with anchors with arthroscopic anchorless TO RCR at a minimum of 2 years postoperatively.

Methods

The study population included patients who underwent RCR using either an anchorless TO technique with a TO suture passing device (group A) and those who were matched for tear size and underwent RCR using suture anchors for repair (group B). The inclusion criterion was an easily reducible rotator cuff tear with a sagittal extension of 2 to 4 cm. After a minimum of 2 years, clinical outcome scores and magnetic resonance imaging were obtained. Tendon quality and footprint integration were evaluated using the Sugaya classification.

Results

Seventy patients were included. A total of 45 were in group A and 25 were in group B. Group A had 2 bone tunnels and 4 sutures using an X-box configuration, and group B had a suture bridge construct of 4 anchors. Group A and B had identical anteroposterior tear size and were comparable for age. The Constant score improved from 50 ± 17.4 to 88 ± 8.6 in group A versus 48 ± 14.5 to 87 ± 7.2 in B. The Subjective Shoulder Value rose from 47 ± 19.1 to 95 ± 7.4 in group A vs from 47 ± 19.4 to 95 ± 7.6 in B. Neither the preoperative (P ≥ .502) nor postoperative scores (P ≥ .29) showed a significant difference. Magnetic resonance imaging showed 2 small retears in group A and one in B, resulting in an identical 4% retear rate. The mean Sugaya type was 2.02 versus 2.24 (P = .206) for groups A versus B.

Conclusions

Anchorless TO RCR is a valid alternative to suture anchor techniques. Clinical outcome data showed comparable results for both techniques after a follow-up of 2 years. The healing results as observed on magnetic resonance imaging were also equivalent for both groups.

Level of Evidence

Level III, retrospective comparative study.

Knotted Transosseous-Equivalent Technique for Rotator Cuff Repair Shows Superior Biomechanical Properties Compared With a Knotless Technique: A Systematic Review and Meta-analysis

PURPOSE

To compare the biomechanical properties of the knotted versus knotless transosseous-equivalent (TOE) techniques for rotator cuff repair (RCR).

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using PubMed, Embase, and the Cochrane Library to identify studies that compared the biomechanical properties of knotted and knotless TOE RCR techniques. The search phrase used was as follows: (Double Row) AND (rotator cuff) AND (repair) AND (biomechanical). Evaluated properties included ultimate load to failure, cyclic displacement, stiffness, footprint characteristics, and failure mode.

RESULTS

Eight studies met the inclusion criteria, including a total of 67 specimens in each group. Of 6 studies reporting on ultimate load to failure, 4 found tendons repaired with the knotted TOE technique to experience significantly higher ultimate load to failure compared with knotless TOE repairs (knotted range, 323.5-549.0 N; knotless range, 166.0-416.8 N; P < .05). Of 6 studies reporting on failure stiffness, 2 found knotted TOE repairs to have significantly higher failure stiffness compared with knotless TOE repairs (knotted range, 30.0-241.8 N/mm; knotless range, 28.0-182.5 N/mm; P < .05), whereas 1 study found significantly higher failure stiffness in knotless TOE repairs compared with knotted TOE repairs (P = .039). Cyclic gap formation favored the knotted TOE group in 2 of 3 studies (knotted range, 0.6-5.2 mm; knotless range, 0.4-9.1 mm; P < .05). The most common mode of failure in both groups was suture tendon tear.

CONCLUSIONS

On the basis of the included cadaveric studies, rotator cuff tendons repaired via the knotted TOE technique display superior time-zero biomechanical properties, including greater ultimate load to failure, compared with rotator cuffs repaired via the knotless TOE technique. Suture tearing through the tendon remains a common failure method for both techniques.

CLINICAL RELEVANCE

The results of this systematic review provide helpful insight into the biomechanical differences between 2 popular techniques for RCR. Although these results should be carefully considered by surgeons who are using either of these techniques in the operating room, they should not be mistaken for direct clinical applicability because cadaveric studies may not directly correlate to clinical outcomes.

Current concepts on management of cuff tear

Among pathologies of the shoulder, rotator cuff tear is the most common. Diagnosis of cuff tear around mid twenties is unusual, but the prevalence increases significantly after the age of forty. The prevalence after the age of 60 is around 20-30%. A well recognised feature of cuff tear is being asymptomatic but, tear progression in asymptomatic is a known consequence. The spectrum of cuff tear ranges from partial, full thickness cuff tear with or without retraction. The mainstay of treatment for partial thickness cuff tear is systematic rehabilitation and for the full thickness cuff tear an initial rehabilitation is an accepted management. Failed rehabilitation for 3 months, acute traumatic tear, younger age, intractable pain, good quality muscle would be the indications for repair of a full thickness cuff tear. Though there are defined indications for surgical intervention in the full thickness rotator cuff tear, differentiating an asymptomatic tear that would not progress or identifying a tear that would become better with rehabilitation is an undeniable challenge for even the most experienced surgeon. Rehabilitation in cuff tear consists of strengthening the core stabilizers along with rotator cuff and deltoid muscles. In a symptomatic cuff tear that merits surgical intervention the objective is to do an anatomical foot print repair. In scenarios where the cuff is retracted, one has to settle for a medialised repair. As, a repair done in tension is more likely to fail than a tensionless medialised repair. The success rate of all these non anatomical procedures varies from series to series but it approximates around 60-80%. Augmenting cuff repair to enhance biological healing is a recent advance in rotator cuff repair surgery. The augmentation factors can be growth factors like PRP, scaffolds both auto and allografts. The outcome of these procedures from literature has been variable. As there are no major harmful effects, it can be viewed as another future step in bringing better outcomes to patients having rotator cuff tear surgery. Despite being the commonest shoulder pathology, the rotator cuff tear still remains as a condition with varied presenting features and a wide variety of management options. The goal of the treatment is to achieve pain free shoulders with good function. Correcting altered scapular kinematics by systematic rehabilitation of the shoulder would be the first choice in all partial thickness cuff tear and also as an initial management of full thickness cuff tears. Failure of rehabilitation would be the step forward for a surgical intervention. While embarking on a surgical procedure, correct patient selection, sound surgical technique, appropriate counselling about expected outcome are the most essential in patient satisfaction.

Biomechanical Properties of Double-Row Transosseous Rotator Cuff Repair Combined With the Cinch Stitch in the Lateral Row

Background:

The self-cinching stitch has been verified to have high mechanical strength. The mechanical strength of combining transosseous rotator cuff repair (RCR) and the self-cinching stitch in the lateral row is unknown.

Purpose/Hypothesis:

The purpose of this study was to evaluate the biomechanical properties of transosseous RCR combined with the cinch stitch in the lateral row. We hypothesized that this construct would have better mechanical strength than would transosseous repair using a vertical cinch stitch or simple stitch.

Study Design:

Controlled laboratory study.

Methods:

Rotator cuff tears were simulated in 48 porcine shoulder specimens. The tears were repaired using 1 of 6 repair configurations: 2–simple stitch transosseous repair alone (group 2TO), with a vertical cinch stitch (group 2TO-VC), or with a horizontal cinch stitch (group 2TO-HC) or 4–simple stitch transosseous repair alone (group 4TO), with a vertical cinch stitch (group 4TO-VC), or with a horizontal cinch stitch (group 4TO-HC). All specimens were set at a 45° angle from the footprint and underwent cyclic loading from 10 to 160 N for 200 cycles, followed by a load-to-failure test at 10 mm/min.

Results:

During cyclic loading, all specimens in group 2TO and half of the specimens in group 2TO-VC failed by suture pullout. In the other groups, none of the specimens failed before 200 cycles. The yield load in group 2TO-HC was significantly greater than that in group 2TO-VC (261.43 vs 219.54 N, respectively; P < .05). There were significant differences between groups 4TO-HC and 4TO with regard to elongation (3.92 vs 5.68 mm, respectively), yield load (304.04 vs 246.94 N, respectively), and linear stiffness (63.44 vs 52.28 N/mm, respectively) (P < .01 for all). Group 4TO-HC also had shorter elongation and a superior yield load and linear stiffness compared with group 2TO-HC (P < .05 for all), and group 4TO-VC had shorter elongation and a stronger maximum load to failure and yield load than did group 2TO-VC (P < .05 for all).

Conclusion:

Increasing the number of medial simple stitches can prevent suture pullout. Adding the horizontal cinch stitch to the lateral row in transosseous repair can further improve biomechanical properties through a self-cinching mechanism.

Clinical Relevance:

Transosseous RCR with a horizontal cinch stitch in the lateral row may reduce the retear rate.

Volumetric MicroCT Intensity Histograms of Fatty Infiltration Correlate with the Mechanical Strength of Rotator Cuff Repairs: An Ex Vivo Rabbit Model

BACKGROUND

Fatty infiltration of the rotator cuff occurs after injury to the tendon and results in a buildup of adipose in the muscle. Fatty infiltration may be a biomarker for predicting future injuries and mechanical properties after tendon repair. As such, quantifying fatty infiltration accurately could be a relevant metric for determining the success of tendon repairs. Currently, fatty infiltration is quantified by an experienced observer using the Goutallier or Fuchs staging system, but because such score-based quantification systems rely on subjective assessments, newer techniques using semiautomated analyses in CT and MRI were developed and have met with varying degrees of success. However, semiautomated analyses of CT and MRI results remain limited in cases where only a few two-dimensional slices of tissue are examined and applied to the three-dimensional (3-D) tissue structure. We propose that it is feasible to assess fatty infiltration within the 3-D volume of muscle and tendon in a semiautomated fashion by selecting anatomic features and examining descriptive metrics of intensity histograms collected from a cylinder placed within the central volume of the muscle and tendon of interest.

QUESTIONS/PURPOSES

(1) Do descriptive metrics (mean and SD) of intensity histograms from microCT images correlate with the percentage of fat present in muscle after rotator cuff repair? (2) Do descriptive metrics of intensity histograms correlate with the maximum load during mechanical testing of rotator cuff repairs?

METHODS

We developed a custom semiautomated program to generate intensity histograms based on user-selected anatomic features. MicroCT images were obtained from 12 adult female New Zealand White rabbits (age 8 to 12 months, weight 3.7 kg ± 5 kg) that were randomized to surgical repair or sham repair of an induced infraspinatus defect. Intensity histograms were generated from images of the operative and contralateral intact shoulder in these rabbits which were presented to the user in a random order without identifying information to minimize sources of bias. The mean and SD of the intensity histograms were calculated and compared with the total percentage of the volume threshold as fat. Patterns of fat identified were qualitatively compared with histologic samples to confirm that thresholding was detecting fat. We conducted monotonic tensile strength-to-failure tests of the humeral-infraspinatus bone-tendon-muscle complex, and evaluated associations between histogram mean and SDs and maximum load.

RESULTS

The total percentage of fat was negatively correlated with the intensity histogram mean (Pearson correlation coefficient -0.92; p < 0.001) and positively with intensity histogram SD (Pearson correlation coefficient 0.88; p < 0.001), suggesting that the increase in fat leads to a reduction and wider variability in volumetric tissue density. The percentage of fat content was also negatively correlated with the maximum load during mechanical testing (Pearson correlation coefficient -78; p = 0.001), indicating that as the percentage of fat in the volume increases, the mechanical strength of the repair decreases. Furthermore, the intensity histogram mean was positively correlated with maximum load (Pearson correlation coefficient 0.77; p = 0.001) and histogram SD was negatively correlated with maximum load (Pearson correlation coefficient -0.72; p = 0.004). These correlations were strengthened by normalizing maximum load to account for animal size (Pearson correlation coefficient 0.86 and -0.9, respectively), indicating that as histogram mean decreases, the maximum load of the repair decreases and as histogram spread increases, the maximum load decreases.

CONCLUSION

In this ex vivo rabbit model, a semiautomated approach to quantifying fat on microCT images was a noninvasive way of quantifying fatty infiltration associated with the strength of tendon healing.

CLINICAL RELEVANCE

Histogram-derived variables may be useful as surrogate measures of repair strength after rotator cuff repair. The preclinical results presented here provide a foundation for future studies to translate this technique to patient studies and additional imaging modalities. This semiautomated method provides an accessible approach to quantification of fatty infiltration by users of varying experience and can be easily adapted to any intensity-based imaging approach. To translate this approach to clinical practice, this technique should be calibrated for MRI or conventional CT imaging and applied to patient scans. Further investigations are needed to assess the correlation of volumetric intensity histogram descriptive metrics to clinical mechanical outcomes.

Anchorless Arthroscopic Transosseous and Anchored Arthroscopic Transosseous Equivalent Rotator Cuff Repair Show No Differences in Structural Integrity or Patient-reported Outcomes in a Matched Cohort

BACKGROUND

Anchored transosseous equivalent suture-bridge technique (TOE) is widely used for arthroscopic rotator cuff repair. It is unknown how patient outcomes scores, ROM, and integrity of the rotator cuff after repair using this anchored technique compare with those after repair using an anchorless transosseous technique (TO).

QUESTIONS/PURPOSES

(1) What are the differences in patient-reported outcomes (American Shoulder and Elbow Surgeons [ASES] score) and shoulder ROM between TO and TOE rotator cuff repair techniques at 1 and 2 years after surgery? (2) What is the difference in repair integrity as measured by the re-tear rate, assessed ultrasonographically at 1 year, between these two techniques? (3) What is the difference in procedure duration between the two techniques when performed by a surgeon familiar with each?

METHODS

We reviewed 331 arthroscopic rotator cuff repairs performed by one surgeon from December 2011 to July 2016 in this retrospective, matched-pair study. Of these patients, 63% (208 of 331) underwent repair with standard anchored technique (anchors placed in a double-row, TOE manner) and 37% (123 of 331) underwent anchorless TO repair, with the same indications for surgery between groups. Forty-four percent (91 of 208) of patients in the TOE group and 61% (75 of 123) of patients in the TO group met the inclusion criteria. Eighty percent (73 of 91) of patients in the TOE group and 88% (66 of 75) in the TO group had minimum 2-year follow-up. We matched each group to a cohort of 50 patients by sex, age, smoking status, and tear size (by Cofield classification: small, < 1 cm; medium, 1-3 cm; large, > 3-5 cm; or massive, > 5 cm). The resulting cohorts did not differ in mean age (TO, 62 years [range 53-65 years]; TOE, 58 years [range 53-65 years]; p = 0.79), mean BMI value (TO, 30 [range 27-33]; TOE, 29 [range 27-35]; p = 0.97), or dominant arm involvement (TO, 80%; TOE, 78%; p = 0.81). The cohorts were followed for at least 2 years (median, 3.2 years [interquartile range (IQR) 2.2-4.3] for TO and 2.9 years [IQR 2.0-3.5 years] for TOE). ASES scores and ROM were evaluated before surgery and at follow-up visits and were recorded in a longitudinally maintained institutional database. Repair integrity was assessed using ultrasonography at 1 year, as is standard in our practice. For each tear-size group, we calculated the proportion of intact tendon repairs versus the proportion of re-tears. Duration of surgery was recorded for each patient.

RESULTS

At 1 year, we observed no difference in median ASES scores (90 [IQR 92-98] for TO and 88 [IQR 72-98] for TOE; p = 0.44); external rotation (50° [IQR 45°-60°) for TO and 50° [IQR: 40°-60°] for TOE; p = 0.58); forward flexion (165° [IQR 160°-170°] for both groups; p = 0.91); or abduction (100° [IQR 90°-100°] for TO and 90° [IQR 90°-100°] for TOE; p = 0.06). Fourteen percent of shoulders (seven of 50) in each treatment group had evidence of re-tear at 1 year (p > 0.99): 0 of 2 small tears in each group, 0 of 7 medium tears in each group, five of 32 large tears in each group, and two of 9 massive tears in each group (all, p > 0.99). At 2 years, we found no differences in median ASES scores (92 [IQR 74-98)] for TO and 90 [IQR 80-100] for TOE; p = 0.84); external rotation (60° [IQR 50°-60°] for both groups; p = 0.74); forward flexion (170° [IQR 160°-170°] for both groups; p = 0.69); or abduction (100° [IQR 90°-100°] for both groups; p = 0.95). We found no differences between groups in mean ± SD procedure time, which was 103 ± 20 minutes for TO repair and 99 ± 20 minutes for TOE repair (p = 0.45).

CONCLUSIONS

TO and TOE techniques for arthroscopic rotator cuff repair results in no differences in ROM, ASES scores, re-tear rates, and surgical time. Randomized control trials are needed to confirm these similarities or determine a superior method of repair. Future cost analyses may also help to determine the relative value of each technique.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Comparison of the clinical and radiological outcomes of arthroscopic transosseous and transosseous-equivalent double-row rotator cuff repair techniques

OBJECTIVE

This study compared the clinical and radiological results of the arthroscopic transosseous (ATO) and transosseous-equivalent (TOE) double-row rotator cuff repair techniques.

METHODS

Prospective data collected from patients treated with ATO (32 women and 7 men, mean age: 57.03±6.39 years) and TOE (36 women and 8 men; mean age: 57.86±7.81 years) techniques were retrospectively evaluated. The visual analog scale score, Constant score, and Oxford shoulder score were used to assess the clinical results. Anchor pullout on standard anteroposterior shoulder radiographs and rotator cuff re-tear on magnetic resonance images were examined at the final follow-up to evaluate the radiological results. Rotator cuff re-tears were graded as per the classification system described by Sugaya et al. Results: The mean follow-up duration was 33.3±11.8 months. No difference was observed in the demographic data of the two groups. Significant improvement was observed in the postoperative shoulder scores of the groups; however, no difference was observed between the groups. Re-tear was detected in 10 patients of the TOE group and 9 patients of the ATO group. Age, tear size, and retraction level could cause re-tear.

CONCLUSION

In the treatment of rotator cuff tears, the ATO and TOE techniques may achieve considerable improvements in shoulder functions in the short term.

LEVEL OF EVIDENCE

Level III, Therapeutic study.

Effect of affective temperament on outcome of rotator cuff surgery

INTRODUCTION

Although numerous risk factors have been described, the effects of temperament, which is defined as a risk factor for certain disorders, on the outcome of patients undergoing rotator cuff surgery have not been investigated.

HYPOTHESIS

We investigated whether a relationship exists between affective temperament and the outcome of patients undergoing rotator cuff surgery.

MATERIAL AND METHODS

The outcomes of 176 patients undergoing rotator cuff surgery were examined using the Oxford and Constant questionnaires as well as visual analog scale values preoperatively and postoperatively. Inclusion criteria were defined as 1) dissatisfaction with pain despite 6 months of nonoperative treatment; 2) rotator cuff defects with full-thickness, small- to large-sized defects; 3) presence of a single dominant temperament or nondominant temperament; 4) no history of a diagnosed psychiatric disorder; and 5) a minimum of greater than 1 year of follow-up after surgery. Exclusion criteria were 1) other comorbid shoulder pathology; 2) irreparable or partial rotator cuff rupture; 3) grade 3 retractions; 4) grade 3-4 fatty infiltration; 5) other comorbid diseases such as diabetes, thyroid disorders, or inflammatory diseases; 6) history of shoulder surgery; 7) infection of the shoulder joint; 8) neurologic deficit in muscles around the shoulder; 9) two or more dominant temperaments; and 10) history of acromioclavicular joint resection and/or biceps tenodesis with cuff repair. All patient temperaments were evaluated according to the Temperament Evaluation of Memphis, Pisa, Paris and San Diego auto questionnaire version.

RESULTS

The mean follow-up time was 45.5 months. The outcomes of patients with depressive temperament were worse than of patients with a nondominant temperament. This situation was observed both preoperatively and postoperatively. However, a similar relationship between nondominant and anxious temperament groups was observed only postoperatively.

CONCLUSION

We noticed that depressive and anxious temperaments had a negative effect on patient outcomes after rotator cuff surgery; however, nondominant temperaments had a positive effect on patient outcomes.

LEVEL OF EVIDENCE

Level III; Retrospective Comparative Study.

True Transosseous Hybrid Rotator Cuff Repair

Transosseous repair has been used safely and effectively for primary and revision rotator cuff repair for decades; as a result, it is considered by many the historical gold standard of open repair techniques. Transosseous repair offers the advantage of excellent biology, double-row anatomic footprint reconstruction, and the ability to create multiple low-cost fixation points per surface area of tendon with high-strength suture, while avoiding anchor pullout, cyst formation, and imaging artifact. More recently, in arthroscopic applications, transosseous-equivalent anchor-based repairs have been introduced that have shown satisfactory clinical and biomechanical results; however, these attributes have been coupled with increased cost, nonbiologic burden to the healing interface of the tendon, and new catastrophic failure modes including tendon transection, anchor pullout, and bone voids. This article delineates a technique for arthroscopic true transosseous hybrid cuff repair that combines the use of anchors and transosseous techniques to maximize the benefits and minimize the detriments of both techniques. Level 1 (shoulder); level 2 (rotator cuff).

Arthroscopic Rotator Cuff Repair in 2019: Linked, Double Row Repair for Achieving Higher Healing Rates and Optimal Clinical Outcomes

The primary aim of rotator cuff repair surgery is to restore the musculotendinous units by creating a complete, tension-free repair construct that optimizes conditions for tendon-to-bone healing. There are many factors outside the control of the surgeon that are capable of affecting the healing process; however, there are also a number of important technical considerations that the surgeon can control, including familiarity with methods to deal with immobile tissues and techniques to perform novel repair constructs. It is clear that linked double row repairs are more likely to heal, and healed rotator cuff repairs best restore shoulder strength, improve patients' satisfaction, and maximize functional outcomes.

Biomechanical Strength of Rotator Cuff Repairs: A Systematic Review and Meta-regression Analysis of Cadaveric Studies

BACKGROUND

Biomechanical cadaveric studies of rotator cuff repair (RCR) have shown that transosseous equivalent and double-row anchored repairs are stronger than other repair constructs.

PURPOSE

To identify technical and procedural parameters that most reliably predict biomechanical performance of RCR constructs.

STUDY DESIGN

Systematic review.

METHODS

The authors systematically searched the EMBASE and PubMed databases for biomechanical studies that measured RCR performance in cadaveric specimens. The authors performed a meta-regression on the pooled data set with study outcomes (gap formation, failure mode, and ultimate failure load) as dependent variables and procedural parameters (eg, construct type, number of suture limbs) as covariates. Stratification by covariates was performed. An alpha level of .05 was used.

RESULTS

Data from 40 eligible studies were included. Higher number of suture limbs correlated with higher ultimate failure load (β = 38 N per limb; 95% CI, 28 to 49 N) and less gap formation (β = -0.6 mm per limb; 95% CI, -1 to -0.2 mm). Other positive predictors of ultimate failure load were number of sutures, number of mattress stitches, and use of wide suture versus standard suture. When controlling for number of suture limbs, we found no significant differences among single-row anchored, double-row anchored, transosseous equivalent, and transosseous repairs. Higher number of suture limbs and transosseous equivalent repair both increased the probability of catastrophic construct failure.

CONCLUSION

This study suggests that the number of sutures, suture limbs, and mattress stitches in a RCR construct are stronger predictors of overall strength than is construct type. There is a need to balance increased construct strength with higher risk of type 2 failure.

Arthroscopic Transosseous Anchorless Rotator Cuff Repair Using the X-Box Technique

We describe a reproducible, step-by-step arthroscopic technique for anchorless transosseous rotator cuff repair using an X-box configuration with the Arthrotunneler device. The technique uses 2 bone tunnels and 4 high-strength sutures and is suitable for medium to large tears of the supra- and infraspinatus that would alternatively need a double-row repair with 4 anchors. Biomechanically, results appear to be similar as for anchored transosseous equivalent techniques. Enhanced biological healing and lower material costs are the possible benefits of this appealing arthroscopic approach that mimics the previous gold standard.

Graft use in the treatment of large and massive rotator cuff tears: an overview of techniques and modes of failure with MRI correlation

Despite technical advances, repair of large or massive rotator cuff tears continues to demonstrate a relatively high rate of failure. Rotator cuff repair or superior capsular reconstruction (SCR) using a variety of commercially available grafts provides a promising option in patients with tears that may be at high risk for failure or otherwise considered irreparable. There are three major graft constructs that exist when utilizing graft in rotator cuff repair or reconstruction: augmentation at the rotator cuff footprint, bridging, and SCR. Each construct has a unique appearance when evaluated using postoperative magnetic resonance imaging (MRI), and each construct has unique sites that are predisposed to failure. Understanding the basic principles of these constructs can help the radiologist better evaluate the postoperative MRI appearance of these increasingly utilized procedures.

[Arthroscopic rotator cuff surgery : New and established methods]

This present article summarizes established and current developments and aspects of rotator cuff surgery. Achieved milestones as well as current approaches are presented and assessed with respect to their clinical and radiographic impact. Despite biomechanical and technical improvements in modern rotator cuff repair techniques, re-defect and re-tearing rates could not be fully eliminated. Meanwhile, the importance of biological processes around successful tendon-bone reintegration has been increasingly recognized. Hence, this article presents the current scientific standing regarding biological growth factors, platelet-rich plasma and rotator cuff augmentation techniques (with allogenic/autologous grafts). In summary, there are clear biomechanical advantages as well as many promising approaches to biological augmentation; however, the latter have not yet been transferred into regular clinical application.

Pullout strength of cement-augmented and wide-suture transosseous fixation in the greater tuberosity

BACKGROUND

Obtaining strong fixation in low-density bone is increasingly critical in surgical repair of rotator cuff tears because of the aging population. To evaluate two new methods of improving pullout strength of transosseous rotator cuff repair in low-density bone, we analyzed the effects of 1) using 2-mm suture tape instead of no. 2 suture and 2) augmenting the lateral tunnel with cement.

METHODS

Eleven pairs of osteopenic or osteoporotic cadaveric humeri were identified by dual-energy x-ray absorptiometry. One bone tunnel and one suture were placed in the heads of 22 specimens. Five randomly selected pairs were repaired with no. 2 suture; the other six pairs were repaired with 2-mm suture tape. One side of each pair received lateral tunnel cement augmentation. Specimens were tested to suture pullout. Data were fitted to multivariate models that accounted for bone mineral density and other specimen characteristics.

FINDINGS

Two specimens were excluded because of knot-slipping during testing. Use of suture tape versus no. 2 suture conferred a 75-N increase (95% CI: 37, 113) in pullout strength (P<0.001). Cement augmentation conferred a 42-N improvement (95% CI: 10, 75; P=0.011). Other significant predictors of pullout strength were age, sex, and bone mineral density.

INTERPRETATION

We show two methods of improving the fixation strength of transosseous rotator cuff repairs in low-density bone: using 2-mm suture tape instead of no. 2 suture and augmenting the lateral tunnel with cement. These methods may improve the feasibility of transosseous repairs in an aging patient population.