[Patch augmentation of the rotator cuff. A reasonable choice or a waste of money?]

Comparison of Biological Augmentation in Rotator Cuff Repair Using Inflamed Versus Noninflamed Bursal Tissue in Rats

PURPOSE

To examine how augmentation of a rotator cuff repair with inflamed versus noninflamed bursal tissue affects tendon-to-bone healing in a rat model of rotator cuff repair.

METHODS

A total of 136 Sprague-Dawley rats were randomly assigned to an inflamed or noninflamed bursal tissue application group. After detachment, the supraspinatus tendon was reattached with bursal tissue sewn onto the tendon-to-bone interface. The specimens were analyzed biomechanically 6 and at 7 weeks and immunohistologically at 1 and at 7 weeks after surgery.

RESULTS

Immunohistological results showed no significant difference in the percentage of collagen type II in the tendon-to-bone interface at 1 (P = .87) and 7 weeks (P = .42) when using autologous noninflamed bursal tissue in comparison with inflamed bursal tissue specimens. The inflamed bursa group also showed no significant difference in collagen I to III quotient (P = .14) after surgery in comparison with noninflamed bursa groups after surgery. Biomechanical assessment showed that tendon stiffness (P = .87 inflamed versus noninflammed (resp.) P = .1) and the tendon viscoelasticity (P = .12 resp. P = .07) was the same after 6 and 7 weeks when we compared the inflamed bursa with the noninflamed bursa group. There was no significant difference (P = .8 resp. P = .87) in load to failure between in both inflamed and noninflamed bursa groups after 6 and 7 weeks.

CONCLUSIONS

Autologous inflamed bursal tissue derived from the Achilles bursa and implanted to the tendon-to-bone interface after rotator cuff repair facilitates the same histologic and biomechanical healing response as using a noninflamed bursa interposition in rats.

CLINICAL RELEVANCE

During augmentation of a rotator cuff repair, it is irrelevant whether the bursa tissue is inflamed.

Bioactive Patch for Rotator Cuff Repairing via Enhancing Tendon-to-Bone Healing: A Large Animal Study and Short-Term Outcome of a Clinical Trial

Tissue engineering has demonstrated its efficacy in promoting tissue regeneration, and extensive research has explored its application in rotator cuff (RC) tears. However, there remains a paucity of research translating from bench to clinic. A key challenge in RC repair is the healing of tendon-bone interface (TBI), for which bioactive materials suitable for interface repair are still lacking. The umbilical cord (UC), which serves as a vital repository of bioactive components in nature, is emerging as an important source of tissue engineering materials. A minimally manipulated approach is used to fabricate UC scaffolds that retain a wealth of bioactive components and cytokines. The scaffold demonstrates the ability to modulate the TBI healing microenvironment by facilitating cell proliferation, migration, suppressing inflammation, and inducing chondrogenic differentiation. This foundation sets the stage for in vivo validation and clinical translation. Following implantation of UC scaffolds in the canine model, comprehensive assessments, including MRI and histological analysis confirm their efficacy in inducing TBI reconstruction. Encouraging short-term clinical results further suggest the ability of UC scaffolds to effectively enhance RC repair. This investigation explores the mechanisms underlying the promotion of TBI repair by UC scaffolds, providing key insights for clinical application and translational research.

The best options in superior capsular reconstruction

Irreparable massive rotator cuff tears cause pain, loss of function, and a decrease in range of motion, which cause serious disturbances in daily life. Young patients, in particular, are active and have relatively high functional requirements, and their surgical options are limited. Superior capsular reconstruction (SCR) was first proposed for irreparable massive rotator cuff tears, good clinical results have been reported in short-term follow up. Since then, SCR has been used increasingly worldwide for irreparable massive rotator cuff tears, and various studies have been published on clinical outcomes, biomechanical outcomes, surgical techniques, and graft types. This article reviews the optimal graft and surgical options for improving clinical outcomes in SCR.

The Use of Autologous Iliotibial Band With Gerdy's Tubercle for Irreparable Rotator Cuff Tears

Objective

To determine the radiographic and functional outcomes after autologous iliotibial band with Gerdy's tubercle (ITB‐GT) interposition in patients with irreparable rotator cuff tears (IRCTs).

Methods

From December 2015 to March 2017, a total of 16 patients who underwent autologous ITB‐GT interposition for IRCTs were identified, including 4 males and 12 females. The mean age was 56.1 ± 10.3 years (range, 44–67 years). Functional assessment consisted of active range of motion (ROM), Visual Analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Constant–Murley score, and patient satisfaction rate. The tendon integrity and acromiohumeral interval (AHI) were assessed by postoperative magnetic resonance imaging (MRI).

Results

The mean duration of follow‐up was 25.3 ± 3.5 months. At final follow‐up, the patients exhibited significantly improved forward elevation, external rotation, and internal rotation (75.00° ± 13.16° to 159.37° ± 8.51°, t = 26.71, P = 0.001; 17.81° ± 11.54° to 35.31° ± 8.26°, t = 6.57, P = 0.001; 2 to 11, t = 13.10, P = 0.001). Other functional outcomes as measured by VAS score, ASES score, and Constant–Murley score also improved significantly (6.50 ± 1.41 to 1.06 ± 0.93, t = 11.68, P = 0.001; 38.50 ± 8.68 to 81.75 ± 6.80, t = 15.42, P = 0.001; 32.50 ± 8.53 to 77.12 ± 6.72, t = 17.28, P = 0.001). The overall satisfaction rate was 87.5%. The postoperative MRI showed that the tendon integrity was fully intact in 14 patients and partially intact in two patients. The AHI improved significantly from 3.63 ± 1.25 mm preoperatively to 8.37 ± 1.02 mm postoperatively (t = 11.78, P = 0.001).

Conclusion

Autologous ITB‐GT interposition was a useful treatment option for patients with IRCTs, which resulted in significant improvements in active ROM, subjective functional outcomes, and AHI with excellent tendon integrity at a minimum 2‐year follow‐up.

The effect of autologous Achilles bursal tissue implants in tendon-to-bone healing of rotator cuff tears in rats

BACKGROUND

The aim of this study was to investigate the influence of autologous bursal tissue derived from the Achilles bursa on tendon-to-bone healing after rotator cuff tear repair in a rat model.

METHODS

A total of 136 Sprague-Dawley rats were randomly assigned to either an untreated or a bursal tissue application group or biomechanical testing and histologic testing after rotator cuff repair. After separating the supraspinatus tendon close to the greater tuberosity, the tendon was reattached either unaltered or with a bursal tissue interposition sewn onto the interface. Immunohistologic analysis was performed 1 and 7 weeks after supraspinatus tendon reinsertion. Biomechanical testing of the tendon occurred 6 and 7 weeks after reinsertion.

RESULTS

Immunohistologic results demonstrated a significantly higher percentage of Type II collagen (P = .04) after 1 and 7 weeks in the tendon-to-bone interface using autologous bursal tissue in comparison to control specimens. The bursa group showed a significantly higher collagen I to III quotient (P = .03) at 1 week after surgery in comparison to the 7-week postsurgery bursa groups and controls. Biomechanical assessment showed that overall tendon stiffness (P = .002) and the tendon viscoelasticity in the bursa group (P = .003) was significantly improved after 6 and 7 weeks. There was no significant difference (P = .55) in force to failure between the bursa group and the control group after 6 and 7 weeks.

CONCLUSION

Autologous bursal tissue derived from the Achilles bursa and implanted to the tendon-to-bone interface after rotator cuff repair facilitates a faster healing response to re-establish the biologic and biomechanical integrity of the rotator cuff in rats.

A Synthetic Graft With Multilayered Co-Electrospinning Nanoscaffolds for Bridging Massive Rotator Cuff Tear in a Rat Model

BACKGROUND

Graft bridging is used in massive rotator cuff tear (MRCT); however, the integration of graft-tendon and graft-bone is still a challenge.

HYPOTHESIS

A co-electrospinning nanoscaffold of polycaprolactone (PCL) with an "enthesis-mimicking" (EM) structure could bridge MRCT, facilitate tendon regeneration, and improve graft-bone healing.

STUDY DESIGN

Controlled laboratory study.

METHODS

First, we analyzed the cytocompatibility of the electrospinning nanoscaffolds, including aligned PCL (aPCL), nonaligned PCL (nPCL), aPCL-collagen I, nPCL-collagen II, and nPCL-nanohydroxyapatite (nHA). Second, for the EM condition, nPCL-collagen II and nPCL-nHA were electrospun layer by layer at one end of the aPCL-collagen I; for the control condition, the nPCL was electrospun on the aPCL. In 40 mature male rats, resection of both the supraspinatus and infraspinatus tendons was performed to create MRCT, and the animals were divided randomly into EM and control groups. In both groups, one end of the layered structure was fixed on the footprint of the rotator cuff, whereas the other end of the layered structure was sutured with the tendon stump. The animals were euthanized for harvesting of tissues for histologic and biomechanical analysis at 4 weeks or 8 weeks postoperatively.

RESULTS

All scaffolds showed good cytocompatibility in vitro. The graft-tendon tissue in the EM group had more regularly arranged cells, denser tissue, a significantly higher tendon maturing score, and more birefringence compared with the control group at 8 weeks after operation. Newly formed fibrocartilage could be observed at the graft-bone interface in both groups by 8 weeks, but the EM group had a higher graft-bone healing score and significantly more newly formed fibrocartilage than the control group. An enthesis-like structure with transitional layers was observed in the EM group at 8 weeks. Biomechanically, the values for maximum failure load and stiffness of the tendon-graft-bone complex were significantly higher in the EM group than in the control group at 8 weeks.

CONCLUSION

The co-electrospinning nanoscaffold of aPCL-collagen I could be used as a bridging graft to improve early graft-tendon healing for MRCT in a rat model and enhance early enthesis reconstruction in combination with a multilayered structure of nPCL-collagen II and nPCL-nHA.

CLINICAL RELEVANCE

We constructed a graft to bridge MRCT, enhance graft-tendon healing and graft-bone healing, and reconstruct the enthesis structure.

Biomechanical Effects of Fiber Patch Augmentation on Rotator Cuff Repairs

Rotator cuff repairs are a common orthopedic procedure that have a relatively high failure rate when tendon quality is poor. New biotechnology exists that can make tendons with poor quality more amenable to repair. This study examined the biomechanical effects of augmenting a rotator cuff repair with an absorbable fiber patch. Six human cadaveric supraspinatus tendons were prepared into 1-cm wide strips and then repaired to the rotator cuff footprint using a titanium anchor and a single mattress suture. Each shoulder underwent repair with and without a fiber patch. The specimens were subjected to cyclic loading (100 cycles) and load-to-failure (LTF) testing. Gap formation after 100 cycles was measured along with LTF in surviving specimens. Gap formation after 100 cycles was 1.07 mm in the suture-only group and 0.50 mm in the fiber patch-augmented group (P=.002). Load-to-failure was 54.26 N in the suture-only group and 109.53 N in the patch-augmented group (P<.001). The use of a fiber patch to augment rotator cuff repair reduced gap formation and increased LTF. [Orthopedics. 2020; 43(1):42-45.].

How to Use a Graft in Irreparable Rotator Cuff Tears: A Literature Review Update of Interposition and Superior Capsule Reconstruction Techniques

PURPOSE OF REVIEW

To introduce the challenges in addressing irreparable rotator cuff tears and examine the surgical options, specifically interposition grafting and superior capsule reconstruction.

RECENT FINDINGS

Interposition grafting of rotator cuff tears shows promising results in reducing pain and improving function postoperatively and one study demonstrated that it performs significantly better than partial repair alone. Superior capsule reconstruction has become popular rapidly, but given the novelty of the procedure, there is currently a paucity of outcomes data to review. Irreparable rotator cuff tears are a challenging condition with a variety of surgical options available. Two such options-interposition and superior capsule reconstruction-both employ grafts in an attempt to restore joint stability and function. In the past 3 years, literature discussing interposition grafting has explored the different types of grafts, and mostly employed pre-post analysis. The recent superior capsule reconstruction articles strictly used human dermal allograft and offer a variety of surgical techniques without quantitative data.

Porcine Dermis Patch Augmentation of Supraspinatus Tendon Repairs: A Pilot Study Assessing Tendon Integrity and Shoulder Function 2 Years After Arthroscopic Repair in Patients Aged 60 Years or Older

PURPOSE

To investigate the 2-year postoperative clinical and subjective outcomes after arthroscopic rotator cuff repair (ARCR) with xenologous porcine dermal patch augmentation compared with ARCR alone.

METHODS

Patients aged 60 years or older with a complete supraspinatus (SSP) tendon tear underwent primary ARCR with a transosseous-equivalent technique. By use of a matched-pair comparative trial design, a consecutive series of 20 patients receiving additional xenologous porcine dermal patch augmentation (patch group) was matched by tear location with 20 patients who received ARCR only (control group). Prior conservative treatment failed in all patients. Patients with concomitant pathologies precluding accurate repair assessment, partial or open reconstruction, or a latissimus dorsi and/or pectoralis major muscle transfer were excluded. Patients reported daily pain levels for 10 days after surgery. Clinical parameters and various patient-reported outcome scores were documented preoperatively and at 3, 6, and 24 months after surgery. Repair integrity was determined by magnetic resonance imaging or ultrasound at 24 months. Adverse events were recorded. Group outcome differences were analyzed with t tests, Fisher exact tests, and mixed models.

RESULTS

Patients in both groups were aged 67 years on average (range, 60-74 years), and 70% of patients were men. Patients in the patch group had slightly more SSP fatty infiltration preoperatively. Patch surgical procedures were on average 22 minutes longer than control interventions (P = .003). At 24 months, 4 patients and 9 patients were diagnosed with a recurrent SSP tendon defect in the control group (n = 20) and patch group (n = 19), respectively (relative risk, 2.4; P = .096). Of 11 defects (85%) identified as medial cuff failure, 8 occurred in the patch group. Pain rated by all patients decreased from postoperative day 1 to day 10 without any significant group difference (P = .348). No significant group differences were noted for other outcome parameters, and recurrent defects had no relevant effect on functional outcomes. Local complications (including recurrent defects) occurred in 8 patients in the control group and 12 in the patch group (P = .343).

CONCLUSIONS

Our pilot study supports the view that an SSP tear repair with porcine dermal xenograft augmentation does not benefit patients in terms of reducing the risk of a recurrent tendon defect or improving shoulder function up to 24 months after surgical repair.

LEVEL OF EVIDENCE

Level III, therapeutic study, retrospective comparative trial.

A synthetic bridging patch of modified co-electrospun dual nano-scaffolds for massive rotator cuff tear

An electrospun nano-scaffold with two different segments is fabricated to bridge a massive rotator cuff tear successfully.