Rotator cuff repair techniques: Current concepts

Multiaxial filament winding of biopolymer microfibers with a collagen resin binder for orthobiologic medical device biomanufacturing

Multiaxial filament winding is an additive manufacturing technique used extensively in large industrial and military manufacturing yet unexplored for biomedical uses. This study adapts filament winding to biomanufacture scalable, strong, three-dimensional microfiber (3DMF) medical device implants for potential orthopedic applications. Polylactide microfiber filaments were wound through a collagen 'resin' bath to create organized, stable orthobiologic implants, which are sized for common ligament (e.g. anterior cruciate ligament) and tendon (e.g. rotator cuff) injuries and can be manufactured at industrial scale using a small footprint, economical, high-output benchtop system. Ethylene oxide or electron beam sterilized 3DMF samples were analyzed by scanning electron microscopy (SEM), underwent ASTM1635-based degradation testing, tensile testing, ISO 10993-based cytocompatibility, and biocompatibility testing, quantified for human platelet-rich plasma (PRP) absorption kinetics, and examined for adhesion of bioceramics and lyophilized collagen after coating. 3DMF implants had consistent fiber size and high alignment by SEM. Negligible mass and strength loss were noted over 4 months in culture. 3DMF implants initially exceeded 1000 N hydrated tensile strength and retained over 70% strength through 4 months in culture, significantly stronger than conventionally produced implants made by fused fiber deposition 3D printing. 3DMF implants absorbed over 3xtheir weight in PRP within 5 min, were cytocompatible and biocompatible in vivo in rabbits, and could readily bind tricalcium phosphate and calcium carbonate coatings discretely on implant ends for further orthobiologic material functionalization. The additive manufacturing process further enabled engineering implants with suture-shuttling passages for facile arthroscopic surgical delivery. This accessible, facile, economical, and rapid microfiber manufacturing platform presents a new method to engineer high-strength, flexible, low-cost, bio-based implants for orthopedic and extended medical device applications.

Rotator Cuff Repair: Racial Disparities in Operative Time and Utilization of Arthroscopic Techniques

Background Racial disparities are prevalent within the field of orthopedics and include the utilization of varying resources as well as outcomes following surgery. This study investigates racial differences between Black and White patients in the surgical treatment of rotator cuff repair (RCR) and 30-day postoperative complications following RCR. Materials and methods Data were drawn from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to create a study population consisting of Black and White patients who underwent RCR between 2015 and 2019. A bivariate analysis was conducted to compare patient demographics and comorbidities. Multivariate logistic regression, controlling for all significantly linked patient demographics and comorbidities, was performed to examine the relationships between Black race and complications. Results Our analysis included 32,073 patients, of whom 3,318 (10.3%) were Black and 28,755 (89.7%) were White. The female gender, younger age groups, greater BMI groups, ASA classification ≥3, cigarette use, and comorbid congestive heart failure (CHF), diabetes, and hypertension were all significantly associated with patients who identified as Black. We found no significant differences in 30-day postoperative complications between Black and White patients. Furthermore, Black patients were found to be independently associated with a greater likelihood of undergoing arthroscopic RCR versus open RCR, as well as experiencing a longer total operation time of ≥80 minutes. Conclusions We report no differences in 30-day postoperative complications between Black and White patients undergoing RCR between 2015 and 2019. However, Black race was independently associated with higher rates of arthroscopic RCR and longer operative times.

Biocomposite Anchors Have Greater Yield Load and Energy Compared With All-Suture Anchors in an In Vitro Ovine Infraspinatus Tendon Repair Model

Purpose

To compare tensile fatigue and strength measures of biocomposite and all-suture anchors in an ovine humerus-infraspinatus tendon model of rotator cuff repair.

Methods

Infraspinatus tendons on adult ovine humeri were sharply transected at the insertion. One of each pair was assigned randomly for fixation with 2 biocomposite or all-suture anchors. Constructs were tested with 200 cycles of 20 to 70 N tensile load, and gap formation was measured at the incised tendon end every 50 cycles. They were subsequently tested to failure. Outcome measures including fatigue stiffness, hysteresis, creep, and gap formation and tensile stiffness, and yield and failure displacement, load, and energy were compared between anchors.

Results

Biocomposite anchors had greater yield load (134.1 ± 6.5 N, P < .01) and energy (228.6 ± 85.7 J, P < .03) than all-suture anchors (104.7 ± 6.5 N, 169.8 ± 85.7 J). Fatigue properties were not different between anchors, but stiffness and gap formation increased and hysteresis and creep decreased significantly with increasing cycle number.

Conclusions

Although the yield displacement of both anchors was within the range of clinical failure, the tensile yield load and energy of ovine infraspinatus tendons secured to the humerus with 2 single-loaded all-suture anchors in a single row were significantly lower than those secured with 2 biocomposite anchors in the same configuration.

Clinical Relevance

It is important to understand the biomechanical properties for selecting anchors for rotator cuff repair. A direct comparison of fatigue testing followed by failure strength of infraspinatus tendon fixation with all-suture and biocomposite anchors could help guide anchor selection and postoperative mobility recommendations.

Distal Clavicular Resection Worsens Outcomes in Rotator Cuff Repair: A National Database Study

Introduction

Distal clavicular resection (DCR) is a procedure used to alleviate acromioclavicular joint (ACJ) pain, often done alongside rotator cuff repair (RCR). This investigation explored the relationships between DCR and RCR, outcomes of DCR during RCR, and complication rates of DCR.

Methods

This retrospective study used electronic medical record data from the TriNetX database. Cohorts were subdivided based on the timeline of DCR in comparison to RCR, as well as comparing RCR with DCR against RCR without DCR.

Results

In total 46 534 patients underwent RCR with 14.8% (6898) of these patients also undergoing DCR. And 72.8% (5021) had DCR during RCR, and 10.7% (740) had DCR after RCR. Less than 5% (<10) of patients with preexisting ACJ pain required DCR 3 years postoperatively, and 0.002% (78) patients without ACJ pain developed ACJ pain within 3 years. Less that 20 patients underwent DCR within 3 years of being diagnosed with ACJ pain. Patients who had RCR with DCR were more likely to have chronic pain postoperatively (P < .0001).

Conclusion

Patients undergoing RCR do not require subsequent DCR. Performing DCR does not offer significant benefit when compared to performing isolated RCR without DCR in patients with preexisting ACJ pain, but increases risk for ACJ instability and chronic pain.

The effect of medial shift of supraspinatus tendon on the glenohumeral joint motion-a cadaveric study

PURPOSE

Full-thickness retracted massive supraspinatus tears are a challenge for arthroscopic surgeons where multiple options for treatment exist, but medializing the attachment is a relatively easy procedure for which a decision can be taken intraoperatively. We investigate the viability of MATERIAL AND METHODS: Ten freshly thawed cadavers were taken and dissected. The supraspinatus tendon was resected, and then its attachment was progressively medialized. The range of motion (abduction, internal and external rotation) was recorded and compared. As a result, we noted a statistically significant decrease in abduction, internal and external rotation with progressive medialization of the supraspinatus insertion.

CONCLUSION

Medialized repair of the supraspinatus can be performed only to an extent beyond which it compromises glenohumeral motion. We noted a statistically significant decrease in ROM with even a 3 mm medialization of the tendon, but the acceptable medialization has to be determined on a case-to-case basis.

Greater tuberosity morphology is altered in individuals with symptomatic isolated supraspinatus tendon tears

BACKGROUND

In the presence of an isolated supraspinatus tear, the force applied to the greater tuberosity is reduced, which may lead to bony morphologic changes. Thus, diagnostic or surgical identification of landmarks to properly repair the torn tendon might be difficult if the anatomy of the greater tuberosity is altered. The objectives of the study were to assess the presence of the superior, middle, and inferior facets of the greater tuberosity in individuals with symptomatic isolated supraspinatus tendon tears and the associations between tear size, tear location and presence of each facet.

METHODS

Thirty-seven individuals with symptomatic isolated supraspinatus tendon tears were recruited to participate in the study. Individuals underwent a high-resolution computed tomography scan of the involved shoulder and images were segmented to generate subject specific models of each humerus. The vertices comprising each facet were identified; however, if even a single vertex comprising the facet was missing, the facet was considered altered. Percentage agreement for correctly identifying the presence of each facet was determined using 2 additional observers and 5 randomly selected humeri. Ultrasonography was performed to assess anterior-posterior (AP) tear size and tear location. Outcome parameters included presence of the superior, middle, and inferior facets; AP tear size; and tear location. Point-biserial correlations were used to determine the associations between AP tear size, tear location, and presence of the superior, middle, and inferior facets.

RESULTS

Supraspinatus tear size and tear location was 13.1 ± 6.1 mm (range, 1.9-28.3 mm) and 2.0 ± 4.4 mm from the posterior edge of the long head of the biceps tendon (range, 0.0-19.0 mm), respectively. Overall, the superior, middle, and inferior facets were not altered in 24.3%, 29.7%, and 45.9% of individuals, respectively. Percentage agreement between observers was 83.4% on average. No associations were found between tear size or tear location and presence of the superior, middle, or inferior facet (P values ranged from .19 to .74).

CONCLUSION

Individuals with symptomatic isolated supraspinatus tears experience significant alterations in the bony morphology of the greater tuberosity that were irrespective of supraspinatus tear size and location. This information is useful for radiologists and orthopedic surgeons as the altered anatomy may influence the ability to identify important anatomic landmarks during diagnostic imaging or surgical procedures.

Role of ultrasound and MRI in the evaluation of postoperative rotator cuff

Rotator cuff tears are common shoulder injuries in patients above 40 years of age, causing pain, disability, and reduced quality of life. Most recurrent rotator cuff tears happen within three months. Surgical repair is often necessary in patients with large or symptomatic tears to restore shoulder function and relieve symptoms. However, 25% of patients experience pain and dysfunction even after successful surgery. Imaging plays an essential role in evaluating patients with postoperative rotator cuff pain. The ultrasound and magnetic resonance imaging are the most commonly used imaging modalities for evaluating rotator cuff. The ultrasound is sometimes the preferred first-line imaging modality, given its easy availability, lower cost, ability to perform dynamic tendon evaluation, and reduced post-surgical artifacts compared to magnetic resonance imaging. It may also be superior in terms of earlier diagnosis of smaller re-tears. Magnetic resonance imaging is better for assessing the extent of larger tears and for detecting other complications of rotator cuff surgery, such as hardware failure and infection. However, postoperative imaging of the rotator cuff can be challenging due to the presence of hardware and variable appearance of the repaired tendon, which can be confused with a re-tear. This review aims to provide an overview of the current practice and findings of postoperative imaging of the rotator cuff using magnetic resonance imaging and ultrasound. We discuss the advantages and limitations of each modality and the normal and abnormal imaging appearance of repaired rotator cuff tendon.

Medialized Rip-Stop Convergence Technique for Retracted Rotator Cuff Tears

Attempts to restore the anatomical footprint during rotator cuff repair for retracted, relatively immobile tears can be difficult. In some cases, it can lead to excessive tension of the repair. Previous studies have noted improved clinical outcomes when repair tension is not excessive, and medialization of the anatomical footprint has been suggested as a technique that can help surgeons repair large, retracted tears without excessive tension and achieve improved clinical outcomes. Of note, excessive tension when restoring the rotator cuff tendon to the anatomical footprint is not limited to large, retracted tears. In some cases, restoring small- and medium-sized tears to the anatomical footprint also can lead to excessive tension. Therefore, it is not uncommon for the authors to employ some degree of footprint medialization even for repair of small- or medium-sized tears if repair to the anatomical footprint will lead to excess tension. The purpose of this article and video demonstration is to provide instruction for a reproducible rotator cuff technique using a medialized single-row rip-stop construct combined with convergence.

Modified double-pulley suture-bridge techniques with or without medial knot tying show comparable clinical and radiological outcomes in arthroscopic rotator cuff repair

PURPOSE

The optimal technique for arthroscopic rotator cuff repair is still controversial. The aim of this study was to compare modified arthroscopic double-pulley suture-bridge (DPSB) technique with medial knot tying to those without tying, considering clinical and radiological outcomes.

METHODS

This study included 292 patients with large full-thickness rotator cuff tears treated with modified DPSB technique. The patients were divided into 158 cases with medial knot tying (knot-tying group) and 134 without tying (knotless group). At follow-up, clinical outcome was assessed by the Constant score, American Shoulder and Elbow Surgeons (ASES) score, and Shoulder Rating Scale of the University of California at Los Angeles (UCLA) score. The assessment of tendon healing was performed with magnetic resonance imaging (MRI) at a minimum of 12 months postoperatively.

RESULTS

The Constant score, ASES score and UCLA score in the knot-tying and knotless groups all improved significantly from before surgery to 12 months postoperatively (P < 0.05, respectively). No significant differences were observed between groups for each phase evaluated (n.s.). Tendon healing was categorised according to Sugaya's classification. The retearing rate was 27/158 (17.0%) in the knot-tying group and 20/134 (14.9%) in the knotless group, with no statistically significant difference between groups (n.s.). Additionally, the retear was classified using the Cho's classification. When comparing the retear rates of different types independently, no statistically significant differences were found between groups (n.s.).

CONCLUSIONS

The knotless modified DPSB technique showed comparable short-term functional outcomes to those of the knot tying method in large full-thickness rotator cuff tears. Additionally, no significant differences in repair integrity were observed between the two methods. Both techniques can be considered effective treatments for patients with large-sized full-thickness rotator cuff tears.

LEVEL OF EVIDENCE

III.

Magnetic resonance imaging analysis of screw in-type lateral anchor pull-out in large to massive rotator cuff repair in patients older than 60 years

Background

This study was performed to identify the incidence of screw in-type lateral anchor pull-out in patients older than 60 years who underwent rotator cuff repair for large to massive rotator cuff tears (RCT).

Methods

We reviewed 25 patients over 60 who were diagnosed with large to massive RCT and underwent arthroscopic rotator cuff repair in our hospital from March 2017 to February 2021. Preoperative tear size (anterior to posterior, medial to lateral) was measured via preoperative magnetic resonance imaging (MRI). All 25 patients underwent MRI scanning on postoperative day 1 and at 3 months after surgery. The change of anchor position was measured in axial views on MRI images postoperative day 1 and 3 months after surgery. And it was statistically compared according to bone mineral density (BMD), sex, and number of lateral anchors.

Results

Two MRIs (postoperative day 1 and 3 months) in 25 patients were compared. Anchor pull-out occurred in six patients during 3 months (6.7%), and the mean pull-out length difference was 1.56 mm (range, 0.16-2.58 mm). There was no significant difference in the number of pull-out anchors, degree of pull-out difference by comparing BMD (A, BMD≤-2.5; B, BMD>-2.5), sex, or number of anchors used in each surgery (C, two anchors; D, three anchors) (p>0.05).

Conclusions

Pull-out of screw in-type anchors was rarely observed and the mean pull-out length difference was negligibly small in our study. The screw in-type lateral anchor seems to be a decent option without concern of anchor pull-out even in elderly patients.

Arthroscopic Compaction Bone Grafting for Uncontained Bone Defects of the Greater Tuberosity Associated With a Rotator Cuff Retear

Revision rotator cuff repair is a technically demanding procedure that can be complicated by the presence of large peri-implant cysts. When multiple suture anchors are encountered, massive bone defects may need to be addressed to ensure that tendon-bone fixation and healing can be optimized. This Technical Note discusses arthroscopic compaction bone grafting for massive uncontained bone defects of the greater tuberosity associated with revision rotator cuff repair.