Treatment Strategy for Irreparable Rotator Cuff Tears

Mid-term outcomes of arthroscopically assisted lower trapezius tendon transfer using Achilles allograft in treatment of posterior-superior irreparable rotator cuff tear

BACKGROUND

Arthroscopically assisted lower trapezius tendon (aLTT) transfer is one of the treatment options for posterior-superior irreparable rotator cuff tears (PSIRCTs). Although short-term clinical outcomes have shown promising results, there are currently no reported clinical outcomes over a longer follow-up period. This study evaluated the mid-term outcomes of aLTT transfer in patients with a diagnosis of PSIRCT.

METHODS

This retrospective case-series study included patients who underwent aLTT transfer between May 2017 and May 2019. The clinical outcome assessment included the visual analog scale (VAS) pain score, Constant score, American Shoulder and Elbow Surgeons score, University of California-Los Angeles score, Activities of Daily Living Requiring Active External Rotation (ADLER) score, active range of motion, Single Assessment Numeric Evaluation score, and return-to-work rate. The radiographic analysis included the acromiohumeral distance, Hamada grade, and integrity of the transferred tendon at final follow-up. Subgroup analyses were performed based on the integrity of the transferred tendon and the trophicity of the teres minor (Tm).

RESULTS

This study enrolled 36 patients with a mean age of 63.4 years who met the inclusion criteria and were followed up for a mean of 58.2 ± 5.3 months. At final follow-up, the patients showed significant improvement in mean VAS score, Constant score, American Shoulder and Elbow Surgeons score, University of California-Los Angeles score, ADLER score, and active range of motion in all directions except internal rotation. A decrease in the acromiohumeral distance and an increase in the Hamada grade were observed at final follow-up (P = .040 and P = .006, respectively). Retears of the transferred tendon occurred in 7 patients, and postoperative infections developed in 2 individuals. An interesting finding was that the retear group still demonstrated improvement in the VAS score but did not show improvement in external rotation at the side by the final follow-up. Compared with the Tm non-hypertrophy group, the Tm hypertrophy group showed significantly better improvement in external rotation at 90° of abduction and at the side, as well as the ADLER score. Of the study patients, 30 (83.3%) were able to successfully resume their previous work.

CONCLUSION

In this study, aLTT transfer in patients with PSIRCTs demonstrated significant improvements in clinical and radiologic outcomes by the final follow-up. These findings provide support for the mid-term safety and effectiveness of aLTT transfer as a viable joint-preserving treatment option for PSIRCTs. However, larger and longer-term studies are still needed to further validate these findings.

Reinforcement Techniques in Arthroscopic Repair of Large-to-Massive Rotator Cuff Tears: A Comparative Study of Superior Capsule Reconstruction and Patch Graft Augmentation

Background: Large-to-massive rotator cuff tears (LMRCTs) present challenges in achieving successful repair due to factors such as muscle atrophy and tendon retraction. Arthroscopic rotator cuff repair (ARCR) with reinforcement techniques like superior capsule reconstruction (SCR) or patch graft augmentation (PGA) has emerged as a less invasive option to improve shoulder joint stability and prevent retear. This study aimed to compare the clinical and radiological outcomes of SCR and PGA as reinforcement techniques for the arthroscopic repair of LMRCTs. Methods: A single-center retrospective study was conducted on patients undergoing LMRCT repair between January 2019 and December 2021. Patients were divided into two groups: those receiving SCR (Group 1) and those receiving PGA (Group 2). Various clinical parameters including range of motion, functional scores, and radiological assessments were evaluated preoperatively and six months postoperatively. Results: Both SCR and PGA techniques demonstrated significant improvements in the range of motion and clinical scores postoperatively. However, Group 2 showed higher postoperative SST and UCLA scores compared to Group 1. Radiologically, there was a slightly higher retear rate in Group 2, although this was not statistically significant. Group 2 also had a shorter mean duration of surgery compared to Group 1. Conclusions: In the arthroscopic repair of LMRCTs, both SCR and PGA techniques exhibit favorable clinical and radiological outcomes. Despite the simplicity of PGA compared to SCR, it offers comparable results with a shorter surgical duration, making it a feasible reinforcement option for surgeons.

Combined Lower Trapezius and Middle Trapezius Tendon Transfer for Posterior Superior Irreparable Rotator Cuff Tears: A Case Report

Introduction

Irreparable rotator cuff tears (IRCTs) often deteriorate shoulder function, necessitating careful consideration of treatment approaches. While reverse total shoulder arthroplasty (RTSA) is the first line of treatment in patients with arthropathy, preserving the joint is crucial for highly demand patients without arthritis. For those patients, various tendon transfer techniques have been established to address different types of IRCTs, including lower trapezius tendon (LTT) transfer for posterior superior IRCTs (PSIRCTs) and middle trapezius tendon (MTT) transfer for isolated supraspinatus IRCTs (ISIRCTs).

Case Report

A 66-year-old male with persistent right shoulder pain and weakness for 2 years, diagnosed with PSIRCTs, sought an alternative to RTSA due to occupational concerns as a restaurant owner. Preoperatively, patients showed limited range of motion (ROM) and weakness, especially in forward elevation (FE) and external rotation (ER). Radiography and magnetic resonance imaging (MRI) scan indicated superior humeral head translation without advanced arthritis and concurrent tears in the supraspinatus and infraspinatus with atrophy. After the consultation, patients underwent a combined transfer of LTT and MTT with a split Achilles tendon allograft in Y-configuration. By postoperative 1 year, the patient exhibited notable improvement, including reduced pain (VAS 4-2), enhanced function (ASES 50-83, Constant 42-78), and increased ROM (FE, 120°-160° and ER, 10°-40°). Radiographic assessments demonstrated an increased in acromiohumeral distance without arthritic progression. Post-operative MRI confirmed tendon integrity, and the patient successfully resumed work at 6 months.

Conclusion

A combined transfer of the MTT and LTT with a split Achilles tendon allograft in Y-configuration has been shown to alleviate pain, enhance functional scores, and improve the ROM in patients with PSIRCTs without arthritis.

Increased latissimus dorsi and teres major muscle volume after anterior transfer for irreparable anterior superior rotator cuff tear: correlation with improved internal rotation strength

INTRODUCTION

While the well-established correlation between increased muscle volume and enhanced muscle strength is widely recognized, there have been no studies assessing volumetric muscle changes in transfer surgery in the shoulder. This study aimed to evaluate changes in transferred muscle volume and their clinical implications in anterior latissimus dorsi and teres major (aLDTM) tendon transfer in patients with anterior superior irreparable rotator cuff tears (ASIRCTs).

MATERIALS AND METHODS

The study retrospectively examined 40 patients who underwent aLDTM tendon transfers for ASIRCTs between August 2018 and January 2022. Using ImageJ software, the LDTM muscle was segmented in T2-weighted oblique axial images, and total muscle volume (tLDTMV) of both immediate and postoperative 1-year were calculated. Pearson correlation analysis was used to determine the correlation between ΔtLDTMV and ΔASES scores, Δactive-ROM, and Δstrength.

RESULTS

The current study revealed an 11.4% increase in tLDTMV at 1-year postoperative. Patients were grouped based on postoperative ASES score: Group 1 (Optimal, n = 17) and Group 2 (Suboptimal, n = 23). Although tLDTMVimmediate postoperative values were similar between groups (P = 0.954), tLDTMV1-year postoperative value was significantly higher in Group 1 compared to Group 2 (P = 0.021). In correlation analysis, ΔtLDTMV showed significant correlations with ΔASES score (r = 0.525, P < 0.001), ΔaROM of forward elevation (FE) (r = 0.476, P = 0.002), ΔaROM of internal rotation (IR) at back (r = 0.398, P = 0.011), Δstrength of FE (r = 0.328, P = 0.039), Δ strength of IR at 90° abduction (r = 0.331, P = 0.037), and IR at side (r = 0.346, P = 0.029).

CONCLUSIONS

Significant increase in tLDTMV was observed at 1-year postoperative for ASIRCT patients. Notably, greater ΔtLDTMV exhibited a correlation with better ASES scores, increased aROM and strength in both FE and IR. Nevertheless, further research is required by employing more robust standardized measurement tools and a larger sample size.

Joint-preserving treatment for global irreparable rotator cuff tears: combined anterior Latissimus dorsi and Teres major tendon transfer

INTRODUCTION

Treating global irreparable rotator cuff tears (GIRCTs) that involve both antero-and postero-superior cuff tendon tears could be a challenging problem. There has been limited joint-preserving treatment options in high-demand patients with minimal glenohumeral arthritis. The study aims to assess the clinical outcome of combined anterior latissimus dorsi and teres major tendon (aLDTM) transfer for patients with both GIRCTs and minimal glenohumeral arthritis.

MATERIALS AND METHODS

This retrospective study included patients who underwent combined aLDTM transfer for GIRCTs between 2018 May and 2020 October. Clinical outcomes include pain VAS, Constant, American Shoulder and Elbow Society (ASES), University of California Los Angeles (UCLA), activities of daily living requiring active internal rotation (ADLIR) score, active range of motion (aROM), strength, rates of pseudoparalysis or pseudoparesis reversal and return to work. Radiographic assessment included the acromiohumeral distance (AHD), Hamada grade, and transferred tendon integrity at final follow-up.

RESULTS

23 patients (mean age: 64.7 ± 5.9 years [55-74]) were included and the mean follow-up period was 28.2 ± 4.3 [24‒36] months. Postoperatively, VAS, Constant, ASES, UCLA, and ADLIR scores significantly improved at final follow-up (P < .001). Postoperative aROM was significantly improved in forward elevation (FE) to 129° ± 29°, abduction (ABD) to 105° ± t3°, and internal rotation (IR) at back to 5.9 ± 2.5. Strength of both FE and IR were also significantly improved (P < .001). Patients with preoperative pseudoparalysis (2 of 4 patients) and pseudoparesis (6 of 6 patients) experienced a reversal. No significant change in AHD and hamada grade was confirmed at final follow-up. 3 patients experienced partial tear of the transferred tendon.

CONCLUSIONS

In this study, we found significant improvement in clinical outcomes with no significant progression of arthritis by final follow-up. The aLDTM transfer could be an alternative choice of joint-preserving treatment option for young and active patients with GIRCTs and minimal glenohumeral arthritis. However, large and long-term studies should be conducted to establish its adequacy.

STUDY DESIGN

Case series.

LEVEL OF EVIDENCE

IV.

Association between sleep dysfunction and Patient-Reported Outcomes Measurement Information System scores in patients with rotator cuff tears

OBJECTIVES

The purpose of this study was to utilize Patient-Reported Outcomes Measurement Information System (PROMIS) sleep scores to determine the prevalence of sleep dysfunction and its association with other PROMIS scores in patients with rotator cuff tears (RCT).

METHODS

Patients were retrospectively identified using the International Classification of Diseases-10 codes for RCT pathology, and PROMIS outcomes were assessed at multiple visits between November 2017 and February 2020. Generalized linear mixed effects models were fitted with PROMIS sleep score as the predictor variable and other PROMIS scores as the response variable. Additionally, models were fit using a clinically significant dichotomization of PROMIS sleep scores to assess differences in average PROMIS scores.

RESULTS

The study cohort included 481 patients, 201 (41.8 ​%) of whom had disrupted sleep at first visit. A higher percentage of those with disrupted sleep at first visit were female, nonwhite, and not married compared to those with normal sleep. PROMIS scores at first visit differed by sleep category. Higher PROMIS sleep scores were associated with higher anxiety, depression, fatigue, pain intensity, and pain interference scores and lower physical function, social participation, and upper extremity scores. Relationships were similar when dichotomous PROMIS sleep scores were considered.

CONCLUSION

There was a high prevalence of sleep dysfunction in patients with RCT. Sleep disturbance is associated with increased anxiety, depression, fatigue, pain intensity, pain interference and decreased physical function, social participation, and upper extremity function in patients with RCTs.

LEVEL OF EVIDENCE III

Retrospective Cohort Study.

Arthroscopic treatment for rotator cuff injury and frozen shoulder with concomitant rotator cuff injury: analysis of efficacy and factors influencing prognosis

OBJECTIVE

To analyze the efficacy of arthroscopic treatment for patients with rotator cuff injuries and frozen shoulder combined with rotator cuff injuries and assess the factors influencing patient prognosis.

METHODS

A retrospective analysis was performed on 85 patients who underwent arthroscopic surgery at Hanzhong Central Hospital between October 2016 and October 2021, including 42 patients treated for rotator cuff injuries alone (Group A), and 43 patients for frozen shoulder combined with rotator cuff injuries (Group B). Both groups underwent general anesthesia with controlled hypotension during surgery. Treatment outcomes, including shoulder joint functional scores, pain scores, shoulder joint range of motion, and muscle strength were assessed and compared between the two groups before treatment, as well as at 2 weeks and 2 months post-treatment. Quality of life was also evaluated and compared at 2 months post-treatment. Patients were categorized into good and poor prognosis groups based on their outcome, and factors influencing patient prognosis were analyzed.

RESULTS

Before treatment, both groups exhibited relatively low shoulder joint function scores and external rotation angles, coupled with higher pain scores; however, these differences were not significant between groups (all P>0.05). The surgery duration for Group B was notably longer than that of Group A (P<0.05). Nevertheless, there was no significant variance in intraoperative blood loss between the two groups (P>0.05). After a 2-week treatment duration, both groups demonstrated a significant improvement in shoulder joint function score, pain score, and shoulder joint range of motion compared to baseline, but with no statistically significant intergroup differences. However, two months after the treatment, patients in Group A exhibited marked improvements in shoulder joint function score, pain score, shoulder joint range of motion, and overall quality of life compared to Group B (all P<0.05). Furthermore, the therapeutic efficacy in Group A was superior to that in Group B at the 2-month follow-up (P<0.05). Age, comorbid diabetes, metabolic disorders such as thyroid dysfunction, and the extent of shoulder cuff injury were identified as independent risk factors influencing prognosis.

CONCLUSION

Arthroscopic treatment is effective for both frozen shoulder combined with rotator cuff injury and rotator cuff injury alone, with better outcomes observed in patients with rotator cuff injury only. This technique warrants further promotion.

The validity of ultrasound and shear wave elastography to assess the quality of the rotator cuff

OBJECTIVES

US with shear wave elastography (SWE) could reduce the burden and costs of the diagnostic process for patients with rotator cuff disorders. The aim of this study is to investigate the validity of US and SWE in preoperative assessment of fatty infiltration (FI) and muscle atrophy of the supraspinatus (SSP) and infraspinatus (ISP) muscles.

METHODS

Patients with a rotator cuff disorder and a recent shoulder CT or MRI scan were eligible to participate. Goutallier and Warner stages of the SSP and ISP muscle were measured on the scan, for assessment of FI and muscle atrophy, respectively. These findings were compared with shear wave velocities (SWVs) assessed on US. Visual assessment of FI on US was compared with the Goutallier stage. To quantify the amount of muscle atrophy, the occupation ratio between SSP fossa and muscle was measured on MRI and US.

RESULTS

Seventy-eight shoulders were included in the analysis. The correlation found between the occupation ratio on US and Warner and Goutallier stage and ratio on MRI ranged between r =  - 0.550 to 0.589. The Goutallier stage of ISP and SSP muscle assessed on US showed a fair correlation with the Goutallier stage on a scan of r = 0.574 and r = 0.582, respectively. There was a poor correlation between the SWVs and scan results (r =  - 0.116 to 0.07).

CONCLUSION

SWE is not a valid method to measure the amount of FI or muscle atrophy in the SSP muscle. Therefore, SWE is not a suitable alternative for MRI in standard preoperative diagnostics in rotator cuff pathologies.

CLINICAL RELEVANCE STATEMENT

Shear wave elastography should not be used in the diagnostics of rotator cuff pathologies.

KEY POINTS

• There is a fair correlation between the Goutallier stage of the supraspinatus and infraspinatus muscle assessed on MRI and CT and visual assessment of fatty infiltration achieved on US. • Shear wave elastography is not a valid tool for the determination of the amount of fatty infiltration or muscle atrophy. • Shear wave elastography should not be used as a cheaper and less burdensome alternative for diagnostics in rotator cuff pathologies.

Subacromial Balloon Placement Demonstrates No Advantage Over Debridement in the Treatment of Massive Irreparable Rotator Cuff Tears: A Dual-Armed Systematic Review and Meta-analysis of Over 1000 Patients

BACKGROUND

In recent years, the placement of a subacromial balloon (SAB) spacer has emerged as a treatment option for massive irreparable rotator cuff tears (MIRCTs); however, there is significant controversy regarding its utility in comparison with other surgical interventions.

PURPOSE

To compare outcomes after SAB spacer placement versus arthroscopic debridement for MIRCTs.

STUDY DESIGN

Dual-armed systematic review and meta-analysis (level IV evidence).

METHODS

A literature search of PubMed (MEDLINE), Scopus, and CINAHL Complete databases for articles published before May 7, 2022, was conducted to identify patients with MIRCTs undergoing the 2 procedures. For the SAB arm, 14 of 449 studies were considered eligible for inclusion, while 14 of 272 studies were considered eligible for inclusion in the debridement arm.

RESULTS

In total, 528 patients were eligible for inclusion in the SAB arm and 479 patients in the debridement arm, and 69.9% of patients undergoing SAB placement also underwent concomitant debridement. Decreases in the visual analog scale (VAS) pain score and increases in the Constant score were found to be significantly larger after debridement (-0.7 points [P < .001] and +5.5 points [P < .001], respectively), although the Patient Acceptable Symptom State for the VAS was not achieved after either procedure. Both SAB placement and debridement significantly improved range of motion in forward flexion/forward elevation, internal and external rotation, and abduction (P < .001). Rates of general complication were higher after debridement versus SAB placement (5.2% ± 5.6% vs 3.5% ± 6.3%, respectively; P < .001); however, there were no significant differences between SAB placement and debridement in rates of persistent symptoms requiring a reintervention (3.3% ± 6.2% vs 3.8% ± 7.3%, respectively; P = .252) or reoperation rates (5.1% ± 7.6% vs 4.8% ± 8.4%, respectively; P = .552). The mean time to conversion to reverse total shoulder arthroplasty was 11.0 versus 25.4 months, respectively, for the SAB versus debridement arm.

CONCLUSION

While SAB placement was associated with acceptable postoperative outcomes in the treatment of MIRCTs, there was no clear benefit over debridement alone. Shorter operative times coupled with better postoperative outcomes and longer times to conversion to reverse total shoulder arthroplasty rendered debridement a more attractive option. While there may be a role for SAB placement in poor surgical candidates, there is burgeoning evidence to support debridement alone without SAB placement for the treatment of MIRCTs.

Age-different BMSCs-derived exosomes accelerate tendon-bone interface healing in rotator cuff tears model

BACKGROUND

Rotator cuff tears (RCTs) are culprit of shoulder pain and dysfunction. Tendon-bone interface (TBI) mal-healing is an essential contributor to retear after RCTs. Consequently, present project was conducted to investigate the role of bone marrow mesenchymal stem cells (BMSCs)-derived exosomes on TBI healing.

METHOD

Young BMSCs (Y-BMSCs) and Aged BMSCs (A-BMSCs) were isolated from Young (3-month-old) and old (24-month-old) SD rats, and their-derived exosomes (A-BMSCs-exo and Y-BMSCs-exo) were identified. RCTs model was established, and A-BMSCs-exo and Y-BMSCs-exo were injected at the rotator cuff using hydrogel as a vehicle. Pathological changes of TBI were observed by HE, Sirius Red and Oil Red O staining. Western blotting and RT-qPCR were applied to assess the expression of extracellular matrix (ECM)-, tendon cell (TCs)-, osteogenic-, tendon-derived stem cell (TDSCs)- and angiogenic-associated proteins and mRNAs in TBI.

RESULT

Y-BMSCs exhibited increased activity, osteogenic and lipogenic abilities than A-BMSCs. After A-BMSCs-exo and Y-BMSCs-exo treatment, TBI displayed massive sharpey's fibers growing along the tendon longitudinally, and a collagen fiber-chondrocyte migration zone forming a typical tendon-noncalcified fibrocartilage-calcified fibrocartilage-bone structure. A-BMSCs-exo and Y-BMSCs-exo significantly upregulated the expression of collagen Col I/II/III, Aggrecan, TNMD, SCX, Runx2, OPN, CD45, Sox2, CD31 and VEGFR2 in TBI. In vitro, A-BMSCs-exo and Y-BMSCs-exo significantly enhanced the activity of TCs and TDSCs, TDSCs stemness, and reduced the osteogenic and lipogenic capacity of TDSCs. The effect of Y-BMSCs-exo was significantly stronger than that of A-BMSCs-exo.

CONCLUSION

BMSCs-derived exosomes facilitate ECM remodeling, osteogenic differentiation, angiogenesis, and stemness of TDSCs, thereby accelerating TBI healing in RCTs, with better outcomes using young individual-derived BMSCs.

Rotator cuff tears

Rotator cuff tears are the most common upper extremity condition seen by primary care and orthopaedic surgeons, with a spectrum ranging from tendinopathy to full-thickness tears with arthritic change. Some tears are traumatic, but most rotator cuff problems are degenerative. Not all tears are symptomatic and not all progress, and many patients in whom tears become more extensive do not experience symptom worsening. Hence, a standard algorithm for managing patients is challenging. The pathophysiology of rotator cuff tears is complex and encompasses an interplay between the tendon, bone and muscle. Rotator cuff tears begin as degenerative changes within the tendon, with matrix disorganization and inflammatory changes. Subsequently, tears progress to partial-thickness and then full-thickness tears. Muscle quality, as evidenced by the overall size of the muscle and intramuscular fatty infiltration, also influences symptoms, tear progression and the outcomes of surgery. Treatment depends primarily on symptoms, with non-operative management sufficient for most patients with rotator cuff problems. Modern arthroscopic repair techniques have improved recovery, but outcomes are still limited by a lack of understanding of how to improve tendon to bone healing in many patients.

Perioperative glycemic control reduces the risk of retear in diabetic patients following arthroscopic rotator cuff repair: A meta-analysis

BACKGROUND

Previous studies have associated diabetes with reduced shoulder motion, increased pain, and higher postoperative retear risk after arthroscopic rotator cuff repair (ARCR). However, the impact of glycemic control, measured by hemoglobin A1c (HbA1c) levels, on retear and revision rates after ARCR in diabetic patients remains unclear.

METHODS

This systematic review was conducted using the PubMed, Cochrane Library, Web of Science, and Embase databases according to the preferred reporting conventions for systematic reviews and meta-analyses. Only studies that compared retears and revisions in ARCR patients with documented HbA1c levels between controlled and uncontrolled diabetes groups were included. Relevant data were extracted and analyzed using STATA software. The methodological index for nonrandomized studies was employed to assess the risk of bias in the selected studies. Additionally, heterogeneity tests and sensitivity analyses were conducted to evaluate potential heterogeneity within the samples, and publication bias was also detected.

RESULTS

Six studies (4395 patients), including five retrospective cohort studies and one case‒control study, were included. Four of these studies assessed retears involving 253 patients. Lower HbA1c levels, indicating better glycemic control, were significantly associated with reduced retear rates after ARCR in diabetic patients (P = 0.000; odds ratio = 0.242, 95 % confidence interval: 0.128-0.454; I2 = 25 %). For revision evaluations, two studies, with a total of 4142 patients, found no significant difference in rates between controlled and uncontrolled diabetes groups, and no publication bias was detected.

CONCLUSION

Following ARCR in diabetic patients, effective glycemic control significantly reduces retear rates without affecting revisions, and maintaining glycemic control in the postoperative period may contribute to rotator cuff healing.

Mini-Open Fascia Lata Interposition Graft Results In Superior 2-Year Clinical Outcomes When Compared to Arthroscopic Partial Repair for Irreparable Rotator Cuff Tear: A Single-Blind Randomized Controlled Trial

PURPOSE

To evaluate and compare the results of surgical treatment for irreparable rotator cuff tear (IRCT) by the mini-open interposition procedure using fascia lata autograft against outcomes of the arthroscopic partial repair technique.

METHODS

An interventional, prospective, controlled, randomized, single-blinded study involving 2 study groups was conducted. The graft group (n = 20) underwent the mini-open interposition procedure using fascia lata autograft. The control group (n = 22) underwent arthroscopic partial repair. Patients were evaluated using the University of California Los Angeles (UCLA) Shoulder scale, the American Shoulder and Elbow Surgeons (ASES) score, the Constant-Murley (Constant) score, the visual analogue scale (VAS) pain score, active range of motion, frontal flexion strength, retear rates evaluated by magnetic resonance imaging analysis, occurrence of complications, and the minimal clinically important difference (MCID).

RESULTS

The graft group had better UCLA (31.5 vs 28.18, P = .035) (100% exceeded the MCID for the graft group and 95% for the control group), ASES (88.62 vs 77.06, P = .016) (100% exceeded the MCID for both groups), Constant (78.85 vs 61.68, P < .001), and VAS (0.95 vs 2.59, P = .01) scores at the 24-month follow-up. For active forward elevation range, both groups showed no statistically significant differences (168.5 vs 164.54, P = .538). The results for active external and internal rotation were better in the graft group (60.25 vs 40, and 9.1 vs 6.9, P < .001), as was frontal flexion strength (4.24 vs 2.67, P = .005). The graft group also had lower retear rates (15% vs 45.5%, P = .033). No complications were reported.

CONCLUSIONS

Outcomes of surgeries for IRCT by the mini-open interposition procedure using fascia lata autograft and by the arthroscopic partial repair technique showed good results in both groups over time and exceeded the MCID. However, most comparative outcomes between groups showed better results for the interposition procedure.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Compressed sensing magnetic resonance imaging (CS-MRI) diagnosis of rotator cuff tears

OBJECTIVE

The present prospective study was performed to evaluate the diagnostic efficiency of compressed sensing magnetic resonance imaging (CS-MRI) for rotator cuff tears.

METHODS

Between December 1, 2021 and April 1, 2022, 62 patients with suspected rotator cuff tears were admitted to Affiliated Hospital of Jinggangshan University and received CS-MRI and arthroscopy to determine the diagnosis and the disease type of tears. Their medical data were obtained and analyzed to evaluate the clinical feasibility of CS-MRI in diagnosing rotator cuff tears.

RESULTS

Of the 62 cases of suspected rotator cuff tears, 45 were confirmed by arthroscopy, including 31 cases of total tears and 14 partial tears. Using arthroscopic findings as the gold standard for the diagnosis of rotator cuff tears, the sensitivity of clinical signs to diagnose rotator cuff tears was 66.67%, the specificity was 70.59%, and the accuracy was 67.74%, while the sensitivity of CS-MRI in diagnosing rotator cuff tears was 84.44%, the specificity was 88.24%, and the accuracy was 81.54%. The accuracy of CS-MRI was significantly higher than that of clinical signs as determined by chi-square test within groups (P=0.019).

CONCLUSION

CS-MRI provides high resolution for muscles, tendons, and soft tissues, significantly contributing to the diagnosis of soft tissue injuries. Although there were no significant differences in the sensitivity and specificity of CS-MRI for the clinical diagnosis of rotator cuff tears compared to the clinical signs, CS-MRI significantly improved the diagnostic accuracy.

Analysis of differentially expressed genes in torn rotator cuff tendon tissues in diabetic patients through RNA-sequencing

BACKGROUND

Rotator cuff tears (RCT) is a common musculoskeletal disorder in the shoulder which cause pain and functional disability. Diabetes mellitus (DM) is characterized by impaired ability of producing or responding to insulin and has been reported to act as a risk factor of the progression of rotator cuff tendinopathy and tear. Long non-coding RNAs (lncRNAs) are involved in the development of various diseases, but little is known about their potential roles involved in RCT of diabetic patients.

METHODS

RNA-Sequencing (RNA-Seq) was used in this study to profile differentially expressed lncRNAs and mRNAs in RCT samples between 3 diabetic and 3 nondiabetic patients. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were performed to annotate the function of the differentially expressed genes (DEGs). LncRNA-mRNA co-expression network and competing endogenous RNA (ceRNA) network were constructed to elucidate the potential molecular mechanisms of DM affecting RCT.

RESULTS

In total, 505 lncRNAs and 388 mRNAs were detected to be differentially expressed in RCT samples between diabetic and nondiabetic patients. GO functional analysis indicated that related lncRNAs and mRNAs were involved in metabolic process, immune system process and others. KEGG pathway analysis indicated that related mRNAs were involved in ferroptosis, PI3K-Akt signaling pathway, Wnt signaling pathway, JAK-STAT signaling pathway and IL-17 signaling pathway and others. LncRNA-mRNA co-expression network was constructed, and ceRNA network showed the interaction of differentially expressed RNAs, comprising 5 lncRNAs, 2 mRNAs, and 142 miRNAs. TF regulation analysis revealed that STAT affected the progression of RCT by regulating the apoptosis pathway in diabetic patients.

CONCLUSIONS

We preliminarily dissected the differential expression profile of lncRNAs and mRNAs in torn rotator cuff tendon between diabetic and nondiabetic patients. And the bioinformatic analysis suggested some important RNAs and signaling pathways regarding inflammation and apoptosis were involved in diabetic RCT. Our findings offer a new perspective on the association between DM and progression of RCT.

Changes in in vivo three dimensional shoulder kinematics following latissimus dorsi tendon transfer for irreparable posterosuperior rotator cuff tears: A systematic review with meta-analysis

BACKGROUND

Latissimus dorsi transfer is a surgical procedure that can be used for treating posterosuperior rotator cuff tears. The procedure leads to improved shoulder function via alterations in the force vector couple around the shoulder. However, there is still no consensus on the biomechanical changes resulting from latissimus dorsi transfer.

METHODS

We performed a systematic review of the literature on 3D motion analysis studies evaluating the effects of latissimus dorsi transfer on shoulder kinematics. The available data on segment and joint range of motion was extracted and subject to meta-analysis when consistent across the studies.

FINDINGS

Our meta-analysis of pre- and post-operative studies revealed a significant improvement in forward flexion and abduction following latissimus dorsi transfer. When comparing the latissimus transferred shoulder with an uninjured contralateral side the meta-analysis found no significant difference in flexion range of motion, while abduction and external rotation was significantly higher in the uninjured shoulders. The overall risk of bias was moderate to high. High heterogeneity was found in the reporting of data, which limited our ability to perform a meta-analysis across the studies for all interest outcomes.

INTERPRETATIONS

Our findings suggest that latissimus dorsi transfer for posterosuperior rotator cuff tears effectively improves shoulder flexion and abduction. External rotation is also expected to improve but at inferior levels as compared to the unaffected side. However, the heterogeneity of the reported data on 3D motion analysis studies highlights the need for better standardization in research and reporting as to conclude the impact of different joints.

High-frequency Quantitative Ultrasound Imaging of Human Rotator Cuff Muscles: Assessment of Repeatability and Reproducibility

This study evaluated the repeatability and reproducibility of using high-frequency quantitative ultrasound (QUS) measurement of backscatter coefficient (BSC), grayscale analysis, and gray-level co-occurrence matrix (GLCM) textural analysis, to characterize human rotator cuff muscles. The effects of varying scanner settings across two different operators and two US systems were investigated in a healthy volunteer with normal rotator cuff muscles and a patient with chronic massive rotator cuff injury and substantial muscle degeneration. The results suggest that BSC is a promising method for assessing rotator cuff muscles in both control and pathological subjects, even when operators were free to adjust system settings (depth, level of focus, and time-gain compensation). Measurements were repeatable and reproducible across the different operators and ultrasound imaging platforms. In contrast, grayscale and GLCM analyses were found to be less reliable in this setting, with significant measurement variability. Overall, the repeatability and reproducibility measurements of BSC indicate its potential as a diagnostic tool for rotator cuff muscle evaluation.

Evaluation of spin in reviews of biodegradable balloon spacers for massive irreparable rotator cuff tears

HYPOTHESIS

Clinical studies are often at risk of spin, a form of bias where beneficial claims are overstated while negative findings are minimized or dismissed. Spin is often more problematic in abstracts given their brevity and can result in the misrepresentation of a study's actual findings. The goal of this study is to aggregate primary and secondary studies reporting the clinical outcomes of the use of subacromial balloon spacers in the treatment of massive irreparable rotator cuff tears to identify the incidence of spin and find any significant association with study design parameters.

MATERIALS AND METHODS

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Independent searches were completed on 2 databases (PubMed and Embase) for primary studies, systematic and current concepts reviews, and meta-analyses and the results were compiled. Two authors independently screened the studies using a predetermined inclusion criteria and aggregated data including titles, publication journals and years, authors, study design, etc. Each study was independently assessed for the presence of 15 different types of spin. Statistical analysis was conducted to identify associations between study characteristics and spin.

RESULTS

Twenty-nine studies met the inclusion criteria for our analysis, of which 10 were reviews or meta-analyses and 19 were primary studies. Spin was identified in every study except for 2 (27/29, 93.1%). Type 3 spin, "Selective reporting of or overemphasis on efficacy outcomes or analysis favoring the beneficial effect of the experimental intervention" and type 9 spin, "Conclusion claims the beneficial effect of the experimental treatment despite reporting bias" were most frequently noted in our study, both observed in 12/29 studies (41.4%). Date of publication, and adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses or "The International Prospective Register of Systematic Reviews" were study characteristics associated with a higher rate of certain types of spin. There was a statistically significant association between disclosure of external study funding source and the presence of spin type 4, but none of the other forms of spin.

CONCLUSION

Spin is highly prevalent in the abstracts of primary studies, systematic reviews, and meta-analyses discussing the use of subacromial balloon spacer technology in the treatment of massive irreparable rotator cuff tears. Our findings revealed that spin in the abstract tended to favor the balloon spacer intervention. Further efforts are required in the future to mitigate spin within the abstracts of published manuscripts.

Platelet-rich plasma in orthopedics: Bridging innovation and clinical applications for bone repair

In the burgeoning domain of orthopedic therapeutic research, Platelet-Rich Plasma (PRP) has firmly established its position, transforming paradigms ranging from tissue regeneration to the management of chondral lesions. This review delves into PRP's recent integrations with cutting-edge interventions such as 3D-printed scaffolds, its role in bone and cartilage defect management, and its enhanced efficacy when combined with molecules like Kartogenin (KGN) for fibrocartilage zone repair. Significant attention is paid to tissue engineering for meniscal interventions, where a combination of KGN, PRP, and bone marrow-derived mesenchymal stem cells are under exploration. Within the sphere of osteochondral regenerative therapy, the synergy of PRP with Bone Marrow Aspirate Concentrate (BMAC) represents a noteworthy leap towards cartilage regeneration. The innovative incorporation of PRP with biomaterials like hydroxyapatite and graphene oxide further underscores its versatility in supporting structural integrity and ensuring sustained growth factor release. However, while PRP's autologous and nontoxic nature makes it an inherently safe option, concerns arising from its preparation methods, particularly with bovine thrombin, necessitate caution. As of 2023, despite the burgeoning promise of PRP in bone healing, the quest for its standardization, optimization, and substantiation through rigorous clinical trials continues. This comprehensive review elucidates the contemporary applications, challenges, and future trajectories of PRP in orthopedics, aiming to spotlight areas primed for further research and exploration.

Evaluation of spin in systematic reviews on the use of tendon transfer for massive irreparable rotator cuff tears

PURPOSE

To identify, describe and account for the incidence of spin in systematic reviews and meta-analyses of tendon transfer for the treatment of massive, irreparable rotator cuff tears. The secondary objective was to characterize the studies in which spin was identified and to determine whether identifiable patterns exist among studies with spin.

METHODS

This study was conducted per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Each abstract was assessed for the presence of the 15 most common types of spin derived from a previously established methodology. General data that were extracted included study title, authors, publication year, journal, level of evidence, study design, funding source, reported adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, preregistration of the study protocol, and methodologic quality per A Measurement Tool to Assess Systematic Reviews Version 2 (AMSTAR 2).

RESULTS

The search yielded 53 articles, of which 13 were included in the final analysis. Articles were excluded if they were not published in a peer reviewed journal, not written in English, utilized cadaveric or nonhuman models, or lacked an abstract with accessible full text. 53.8% (7/13) of the included studies contained at least 1 type of spin in the abstract. Type 5 spin ("The conclusion claims beneficial effect of the experimental treatment despite a high risk of bias in primary studies") was the most common, appearing in 23.1% (3/13) of included abstracts. Nine of the spin categories did not appear in any of the included abstracts. A lower AMSTAR 2 score was significantly associated with the presence of spin in the abstract (P < .006).

CONCLUSION

Spin is highly prevalent in the abstracts of systematic reviews and meta-analyses concerning tendon transfer for massive rotator cuff tears. A lower overall AMSTAR 2 rating was associated with a higher incidence of spin. Future studies should continue to explore the prevalence of spin in orthopedic literature and identify any factors that may contribute to its presence.

Clinical effects of sodium hyaluronate combined with platelet-rich plasma injection on rotator cuff injury in arthroscopic repair

Objective

Rotator cuff injury is one prevalent shoulder condition that often leads to pain and dysfunction. The study explored the clinical effects of sodium hyaluronate combined with platelet-rich plasma (PRP) injection on rotator cuff injury in arthroscopic repair.

Methods

A total of 92 cases with rotator cuff injury were randomly divided into the control group (n = 46, treated with shoulder arthroscopy repair combined with subacromial space injection of sodium hyaluronate) and the experimental group (n = 46, treated with subacromial space injection of autologous PRP on the basis of the treatment in the control group). Visual analogue scale (VAS), Constant-Murley scale (CMS), University of California, Los Angeles (UCLA), American Shoulder and Elbow Society (ASES), and quality of life (QOL) scores, as well as complications were compared in the two groups before surgery and at 3 and 6 months after surgery. Shoulder range of motion (ROM) was measured before and after surgery.

Results

VAS scores of patients in the two groups at 3 and 6 months after surgery were lower than those before surgery, and the VAS scores of patients in the experimental group at 3 and 6 months after surgery were much lower than those in the control group (all P < 0.05). The scores of CMS, UCLA, ASES, and QOL, and shoulder ROM in both groups at 3 and 6 months after surgery were higher than those before surgery, and these shoulder joint function scores, QOL and shoulder ROM in the experimental group at 3 and 6 months after surgery were higher than those in the control group (all P < 0.05). No statistically significant difference presented in the incidence of complications between the two groups (P > 0.05).

Conclusion

Arthroscopic rotator cuff repair and sodium hyaluronate combined with PRP injection can effectively reduce pain symptoms, improve shoulder joint function and shoulder ROM, and improve QOL in patients with rotator cuff injury.

Contrast-Enhanced Ultrasound-Assessed Supraspinatus Muscle Perfusion Indicates Better Tissue Vitality and Outcome After Supraspinatus Tendon Repair and Subacromial Decompression

OBJECTIVE

Supraspinatus tendon (SSP) tears are a frequent indication for shoulder surgery. Therapy options include physiotherapy, tendon repair and less invasive surgical options like subacromial decompression (SAD). The selection of the most appropriate treatment depends on the specific characteristics and needs of each patient subgroup. Typically, physically active patients are candidates for tendon repair, while a conservative approach is preferred for individuals with severe muscle degeneration or low physical demands. The goal of this study was to assess the impact of contrast-enhanced ultrasound (CEUS)-assessed SSP muscle perfusion on post-operative shoulder function and tendon healing in patients undergoing SSP repair or SAD, thereby enhancing personalized therapy for SSP tendon tears.

METHODS

Two cohorts of patients with SSP tendon tears were treated either by SAD or tendon repair. Pre-operative and 6-month post-operative SSP muscle perfusion was quantified using CEUS and investigated as a surrogate for tissue vitality. The magnetic resonance imaging-derived parameters fatty infiltration and tendon retraction and established shoulder function scores were assessed pre- and post-operatively.

RESULTS

Thirty-five SSP repair patients were compared with 20 SAD patients. Pre-operative perfusion was comparable in the SAD and SSP repair cohorts when a re-tear occurred (wash-in perfusion index = 103.8 ± 124.0 vs. 114.6 ± 155.0, p = 0.83), while being significantly higher among patients with an intact repair (103.8 ± 124 vs. 325.4 ± 388.6, p = 0.006). Below-median pre-operative muscle perfusion was associated with lower post-operative shoulder function (Constant score: 59 ± 28 vs. 78 ± 19, p = 0.012).

CONCLUSION

CEUS can visualize SSP muscle perfusion as a surrogate for tissue vitality and tendon healing, which is associated with better post-operative shoulder function.

Salvaging the 'irreparable' tear: Superior Capsular Reconstruction augmented with partial cuff repair

Introduction

Massive rotator cuff tears (MRCTs) have long posed a complex problem for both patients and surgeons. If not treated promptly, tendon retraction, fatty infiltration and muscle atrophy of the rotator cuff muscles occur. These lead to irreparable RCTs with poor functional outcomes. We describe our technique of superior capsular reconstruction (SCR) augmented with partial cuff repair and report on our short term outcomes.

Method

Seven consecutive patients who underwent the procedure were recruited at our institution from January 2019 to December 2019. Medical records of these patients were reviewed looking at pre-operative symptoms and examination findings, imaging studies, intra-operative findings, the surgical technique employed, post-operative progress in terms of pain, affected shoulder range of movement and outcome scores.

Results

All patients showed complete tears of at least two tendons and were deemed irreparable intra-operatively. All patients exhibited Goutalier grade 2-4 wasting of the affected tendons on MRI and Patte grade 3 intra-operatively. At 12 months, the mean improvement shown in Constant score is 12.1 points, in University of California Los Angeles (UCLA) score is 9.4 points and in Oxford Shoulder Score is 17 points. Active forward flexion improved in all patients with a mean improvement of 40 degrees. Numerical Pain Rating Scale improved in all patients with a mean of 5.1 points.

Conclusion

Our case series shows good short-term outcomes can be achieved with SCR augmented with partial cuff repair. Notably, our SCR results showed encouraging results even for challenging revision rotator cuff repairs.

Comparison of Early versus Traditional Rehabilitation Protocol after Rotator Cuff Repair: An Umbrella-Review

Rehabilitation after rotator cuff repair is crucial for functional recovery and for minimizing the risk of retear. There are two rehabilitation protocols (early and traditional) and the debate about which is the best is open. This umbrella review aimed to compare the effect of these rehabilitation protocols in terms of reduction in pain, functional recovery, and retear risk. We selected systematic reviews and meta-analyses published between 2012 and 2022 dealing with the aim. Nineteen systematic reviews were included. No significant differences were found between early and traditional protocols in terms of pain reduction. Early rehabilitation provided better short-term results regarding Range of Motion improvement, but long-term functional outcomes were similar. Retear risk remains a significant concern for the early protocol. We found major differences between the analyzed protocols. This review suggests that both protocols are useful to recover global shoulder function, but the standard protocol has a greater safety profile for larger tears. On the other hand, the early protocol may be preferable for smaller lesions, allowing a faster recovery and having less impact on medical costs. Further research is needed to identify optimal rehabilitation strategies tailored to the individual patient's needs and characteristics.

Outcomes of subacromial balloon spacer implantation for irreparable rotator cuff tears: a systematic review and meta-analysis

BACKGROUND

The management of irreparable rotator cuff tears remains a topic of considerable debate among orthopedic surgeons. Currently, there is little consensus regarding the gold-standard treatment; however, an emerging option involves the use of a biodegradable subacromial spacer. The purpose of this study, therefore, was to systematically review and synthesize the current literature reporting on the clinical outcomes following implantation of a subacromial balloon spacer (SABS) for the treatment of patients with irreparable rotator cuff tears.

METHODS

A systematic review of the PubMed Central, MEDLINE, Embase, Scopus, and Cochrane Library databases from inception through December 2022 was performed. Clinical outcome studies reporting on functional and clinical outcomes, as well as postoperative complications, were included.

RESULTS

A total of 127 studies were initially identified, of which 28 were deemed eligible for inclusion in our review. Of these studies, 17 reported adequate preoperative and postoperative data (mean and a measure of variance) and thus were included in the meta-analysis. Among the included studies, a total of 894 shoulders (886 patients) were included; the mean age was 67.4 years (range, 61.7-76.2 years). The average follow-up period was 30.4 months (range, 12-56 months). All postoperative patient-reported outcomes improved significantly from baseline, including the Constant score (mean difference, 33.53; P < .001), American Shoulder and Elbow Surgeons score (mean difference, 40.38; P < .001), Oxford Shoulder Score (mean difference, 12.05; P = .004), and visual analog scale pain score or Numeric Pain Rating Scale score (mean difference, -3.79; P < .001). Forward elevation (mean difference, 24°; P < .001), abduction (mean difference, 52°; P = .02), and external rotation (mean difference, 15°; P < .001) improved. Device-related complications occurred at a rate of 3.6%, the most common of which were balloon migration (1.0%) and synovitis (0.6%). Ultimately, 5% of patients required salvage reverse shoulder arthroplasty.

CONCLUSION

Short-term outcomes suggest that SABS implantation can be a safe and effective treatment and appears to be associated with early improvements in postoperative pain and function. Clinical heterogeneity, use of concomitant procedures, and variations in patient selection limit our ability to conclusively interpret the available evidence. We do not yet know the potential therapeutic value of SABS implantation relative to other currently accepted treatment strategies, the length of symptomatic improvement that can be expected, or the long-term implications of SABS use on the outcomes of further salvage procedures.

The Effect of Combining Hyaluronic Acid and Human Dermal Fibroblasts on Tendon Healing

BACKGROUND

The incidence of rotator cuff tears is rapidly increasing, and operative techniques for rotator cuff repair have been developed. However, the rates of postoperative retear remain high.

PURPOSE/HYPOTHESIS

The purpose was to determine the effects of human dermal fibroblasts (HDFs) with hyaluronic acid (HA) on tendon-to-bone healing in a rabbit model of chronic rotator cuff tear injury. It was hypothesized that HA would enhance HDF proliferation and that a combination of HA and HDFs would produce a synergistic effect on the healing of repaired rotator cuff tendons of rabbits.

STUDY DESIGN

Controlled laboratory study.

METHODS

For in vitro study, HDFs were plated on a 24-well plate. After 1 day, 2 wells were designated as the test group and treated with 0.75% HA in phenol red-free Dulbecco's modified Eagle medium (DMEM). An other 2 wells served as control groups and were treated with the same volume of phenol red-free DMEM without HA. Each group was duplicated, resulting in a total of 4 wells, with 2 wells in each group for replication purposes. The cells were incubated for 24 hours, followed by 72-hour cultivation. Absorbance ratios at 96 and 24 hours were compared to evaluate cell proliferation. For the in vivo study, a total of 24 rabbits were randomly allocated to groups A, B, and C (n = 8 each). Supraspinatus tendons were detached bilaterally and left for 6 weeks to establish a chronic rotator tear model. Torn tendons were subsequently repaired using the following injections: group A, 0.5 × 106 HDFs with HA; group B, HA only; and group C, saline only. At 12 weeks after repair, biomechanical tests and histological evaluation were performed.

RESULTS

In vitro study showed that HDF proliferation significantly increased with HA (HDFs with HA vs HDFs without HA; 3.96 ± 0.09 vs 2.53 ± 0.15; P < .01). In vivo, group A showed significantly higher load-to-failure values than the other groups (53.8 ± 6.9 N/kg for group A, 30.6 ± 6.4 N/kg for group B, and 24.3 ± 7.6 N/kg for group C; P < .001). Histological evaluation confirmed that group A showed higher collagen fiber density and better collagen fiber continuity, tendon-to-bone interface maturation, and nuclear shape than the other groups (all P < .05).

CONCLUSION

This controlled laboratory study verified the potential of the combination of HDFs and HA in enhancing healing in a chronic rotator cuff tear rabbit model.

CLINICAL RELEVANCE

A potential synergistic effect on rotator cuff tendon healing may be expected from a combination of HDFs and HA.

Massive rotator cuff tears: algorithmic approach to surgical treatment

The management of massive rotator cuff tears (MRCT) presents a unique challenge to many orthopedic specialists. Unlike tears that are predicted to do well with primary, complete repair, MRCT are affected by tissue retraction, in-elasticity, bursal scarring, muscle atrophy, and fatty degeneration; operative repair thus portends worse healing rates than smaller tears and is associated with recurrent tear rates of up to 91% based on ultrasonography and magnetic resonance imaging (MRI). Rotator cuff tears are a common condition in patients over the age of 50. Thus, multiple advances in treatment strategies have been made to combat the limited efficacy of complete or partial rotator cuff repair in the setting of a massive or irreparable rotator cuff tears. It is of utmost importance that the operating orthopedic surgeon be familiar with these various treatment modalities to best serve the patient and that they harbor these skills within their armamentarium. This article details a review of the current literature including nonoperative and operative treatments for the management of massive and irreparable rotator cuff tears. The primary objective is to propose a literature-based algorithm for the treatment of massive and often irreparable rotator cuff tears to allow for informed ease in the decision-making process.

Subacromial balloon spacers for the treatment of irreparable rotator cuff tears: a review

Massive irreparable rotator cuff tears (RCTs) are a commonly encountered orthopedic condition that can be difficult to treat. Several techniques have been described to manage these tears, with the implantable subacromial balloon spacer being one of the most recent. The device, which has only been approved for clinical use in the United States since 2021, functions by resisting the superior humeral head migration seen in the setting of massive RCTs and restoring normal shoulder biomechanics, as corroborated by cadaveric studies. However, results regarding clinical outcomes have been mixed to date, and further high-quality studies are needed to define the optimal use of the subacromial balloon spacer in the treatment of massive irreparable RCTs.

Cocktail-like gradient gelatin/hyaluronic acid bioimplant for enhancing tendon-bone healing in fatty-infiltrated rotator cuff injury models

The regeneration of enthesis tissue (native tendon-bone interface) at the post-surgically repaired rotator cuff remains a challenge for clinicians, especially with the emergence of degenerative affection such as fatty infiltration that exacerbate poor tendon-bone healing. In this study, we proposed a cocktail-like hydrogel with a four-layer structure (BMSCs+gNC@GH) for enhancing fatty infiltrated tendon-bone healing. As collagen and hyaluronic acid are the main biomacromolecules that constitute the extracellular matrix of enthesis tissue, this hydrogel was composed of UV-curable gelatin/hyaluronic acid (GelMA/HAMA) dual network gel (GH) with nanoclay (NC) and stem cells loaded. The results showed that NC exhibited a cocktail-like gradient distribution in GH, which effectively mimicked the structure of native enthesis and supported the long-term culture and encapsulation of BMSCs. What's more, the gradient variation of NC provided a biological signal for promoting gradient osteogenic differentiation of cells. Based on the in vivo results, BMSCs+gNC@GH effectively promoted fibrocartilage layer regeneration at the tendon-bone interface and inhibited fatty infiltration. Therefore, BMSCs+gNC@GH group exhibited better biomechanical properties. Thus, this cocktail-like implant may be a promising tissue-engineered scaffold for tendon-bone healing, and it provides a new idea for the development of scaffolds with the function of inhibiting degeneration.

Long Head of the Biceps Autograft Performs Biomechanically Similar to Human Dermal Allograft for Superior Capsule Reconstruction After Rotator Cuff Tear

PURPOSE

To provide a biomechanical comparison between human dermal (HD) allograft and long head of biceps tendon (LHBT) autograft with and without posterior side-to-side suturing for superior capsule reconstruction.

METHODS

Eight fresh-frozen cadaveric shoulder specimens were tested in 5 conditions: (1) intact, (2) complete supraspinatus tear, (3) LHBT, (4) LHBT with side-to-side suturing, and (5) HD allograft with side-to-side suturing. Functional abduction force, superior translation of humeral head, translational range of motion, and rotational range of motion were tested at 0°, 30°, 60°, and 90° of abduction within each condition. Data were analyzed using analysis of variance with post-hoc Tukey testing for pairwise comparison, with a significance value set at .05.

RESULTS

Functional abduction force in the LHBT, LHBT + suture, and HD + suture conditions was significantly increased compared with the supraspinatus tear condition at abduction angles of 30° (P = .011, .001, and .017, respectively), 60° (P = .004, .001, and .002, respectively), and 90° (P = .013, .001, and .038, respectively). In addition, superior translation of the humeral head in the LHBT, LHBT + suture, and HD + suture conditions was significantly decreased compared with the tear condition at abduction angles of 30° (P = .03, .049, .03, respectively) and 60° (P = .02, .04, .03, respectively). All 3 reconstructive techniques were statistically identical to the intact rotator cuff condition in regard to translational and rotational range of motion.

CONCLUSIONS

Superior capsule reconstruction with LHBT autograft without side-to-side suturing, LHBT with posterior side-to-side suturing, and HD allograft with posterior side-to-side suturing all equivalently restore functional abduction force and decrease superior translation of the humeral head after a complete supraspinatus tear.

CLINICAL RELEVANCE

Superior capsule reconstruction with long head of the biceps tendon autograft and human dermal allograft both restore functional abduction force and decrease superior translation of the humeral head, while displaying no losses in the range of motion in a cadaveric model.

Increased HbA1c Levels in Diabetics During the Postoperative 3-6 Months After Rotator Cuff Repair Correlated With Increased Retear Rates

PURPOSE

To evaluate whether glycemic control affects the integrity of the repaired rotator cuff during the postoperative healing period after arthroscopic double-row suture bridge rotator cuff repair (RCR) METHODS: We retrospectively reviewed patients with diabetes mellitus (DM) who underwent arthroscopic double-row suture bridge RCR at our institution between March 2016 and November 2019. We included the patients who evaluated for serum glycosylated hemoglobin (HbA1c) levels within 1 month before and 3-6 months after surgery. Magnetic resonance imaging was conducted 6 months after surgery to evaluate the integrity of the repaired cuff tendon. Patients were categorized into two groups based on comparison between preoperative and postoperative HbA1c values: Group I (increased postoperative HbA1c) and Group D (same or decreased postoperative HbA1c). The correlation between preoperative/postoperative HbA1c, HbA1c increase/same or decrease (during the healing period), and post-RCR integrity was evaluated, including various demographic and radiologic factors.

RESULTS

A total of 103 patients were analyzed, group I was 47, and group D was 56, respectively. The retear rate of 51.1% (24/47) in Group I was significantly higher than 14.3% (8/56) in Group D (P < .001). HbA1c levels measured 3-6 months after surgery (mean: 6.9; 95% CI: 6.6-7.3 vs mean: 6.5; 95% CI: 6.3-6.7, P = .034), and the proportion of group I and group D were significantly different (75%/25% vs 32.4%/67.6%, P < .001) between the retear and healing groups. Multivariable logistic regression analysis identified increased HbA1c as an independent risk factor for retear (odds ratio: 5.402; 95% CI: 2.072-14.086; P < .001).

CONCLUSIONS

The glycemic control within 3-6 months after surgery when the healing process of the tendon was in progress had a significant effect on retear rate. In particular, the retear rate was higher when the HbA1c level increased at postoperative 3-6 months compared to before surgery.

LEVEL OF EVIDENCE

Retrospective case-control comparative study, Level III.

Biomechanical outcomes of superior capsular reconstruction for irreparable rotator cuff tears by different graft materials-a systematic review and meta-analysis

Background

Irreparable rotator cuff tears (IRCT) are defined as defects that cannot be repaired due to tendon retraction, fat infiltration, or muscle atrophy. One surgical remedy for IRCT is superior capsular reconstruction (SCR), which fixes graft materials between the larger tuberosity and the superior glenoid.

Patients and methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria were followed for conducting the systematic review and meta-analysis. From their inception until February 25, 2022, Pubmed, Embase, and Cochrane Library's electronic databases were searched. Studies using cadavers on SCR for IRCT were also included. The humeral head's superior translation and subacromial peak contact pressure were the primary outcomes. The humeral head's anteroposterior translation, the kind of graft material used, its size, and the deltoid load were the secondary outcomes.

Results

After eliminating duplicates from the search results, 1,443 unique articles remained, and 20 papers were finally included in the quantitative research. In 14 investigations, the enhanced superior translation of the humeral head was documented in IRCTs. In 13 studies, a considerable improvement following SCR was found, especially when using fascia lata (FL), which could achieve more translation restraints than human dermal allograft (HDA) and long head of bicep tendon (LHBT). Six investigations reported a subacromial peak contact pressure increase in IRCTs, which could be rectified by SCR, and these studies found a substantial increase in this pressure. The results of the reduction in subacromial peak contact pressure remained consistent regardless of the graft material utilized for SCR. While there was a statistically significant difference in the change of graft material length between FL and HDA, the change in graft material thickness between FL and HDA was not significant. The humeral head's anterior-posterior translation was rising in IRCTs and could be returned to its original state with SCR. In five investigations, IRCTs caused a significant increase in deltoid force. Furthermore, only one study showed that SCR significantly decreased deltoid force.

Conclusion

With IRCT, SCR might significantly decrease the glenohumeral joint's superior and anterior-posterior stability. Despite the risks for donor-site morbidity and the longer recovery time, FL is still the best current option for SCR.

Infraspinatus shift for massive, posterosuperior tears yields good clinical outcome

AIM

To evaluate the functional outcome of partial reconstruction margin convergence in the treatment of massive, irreparable posterosuperior rotator cuff tear (RCT).

METHODS

This retrospective, single-center study included all patients that were operated by means of a partial repair and infraspinatus shift for a massive, posterosuperior cuff tear between 2009 and 2016, either in arthroscopic or mini-open technique. Outcome measures included sex- and age-adapted Constant Score (saCS), Western Ontario Rotator Cuff (WORC) Index, Disabilities of Arm, Shoulder and Hand Scores (DASH), and relative effect per patient (REPP).

RESULTS

Fifty-six shoulders in 54 patients (mean age: 66 ± 7 years) were evaluated at a mean follow-up of 40 ± 9 months. The mean tear size was Bateman 3.1 ± 0.7 and Patte 2.3 ± 0.4. All clinical scores showed improvement. The saCS improved from 64.1 ± 13.4 to 90.4 ± 13.7 (p < 0.0001), the DASH score from 51.8 ± 9.4 to 10.2 ± 13.4 (p < 0.0001) and the WORC index from 47.1% ± 8.6 to 87.9% ± 13.7 (p < 0.0001). The abduction strength of the affected side (1.7 ± 1.6 kg) was not restored to the same level as the contralateral side (5.4 ± 2.7 kg, p < 0.0001).

CONCLUSION

Partial cuff repair for posterosuperior, massive cuff tears yields good clinical outcome with a low rate of complications and high proportion of good and excellent responders.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Arthroscopic Superior Capsular Reconstruction Using Hamstring Allograft

Superior capsular reconstruction (SCR) has become an acceptable treatment option for patients with chronic shoulder pain in the setting of an irreparable rotator cuff tear. Several different techniques have been described with varying graft options. In this Technical Note, we introduce a technique for arthroscopic SCR using hamstring allograft tendon. Our described technique allows for a "one-size-fits-all" graft with a "build as you go" construct with no need for intraoperative dimensional defect measurements or specific graft modifications. This technique provides a reliable and reproducible procedure using readily available graft tissue.

Revascularization character of autologous fascia lata graft following shoulder superior capsule reconstruction by enhanced magnetic resonance imaging

Background

Fascia lata has been used for arthroscopic superior capsule reconstruction (ASCR) and verified to achieve a good clinical outcome. However, it is still not known about revascularization character of the fascia lata after ASCR. This study was performed to evaluate the revascularization of autologous fascia lata grafts after ASCR by enhanced magnetic resonance imaging (MRI).

Methods

A prospective study of 19 patients with irreparable rotator cuff tears underwent ASCR with autologous fascia lata grafts from September 2019 to April 2021. Radiography examinations and clinical evaluations were performed preoperatively and postoperatively at 6 weeks and 3, 6, and 12 months. The signal-to-noise quotient (SNQ) value and enhancement index (EI) of autologous fascia lata grafts in the great tubercle insertion (GTI), midpoint of the graft (MG), and glenoid insertion (GI) were compared for radiography examination. Clinical evaluation included the American Shoulder and Elbow Surgeons (ASES) score, University of California Los Angeles (UCLA) shoulder score, and Visual Analog Scale (VAS) score.

Results

The SNQ values in T1WI enhancement at GI and GTI were significantly higher than those at the plain MRI scan at all postoperative observation timepoints; however, the SNQ values in T1WI enhancement at MG did not show a significant difference until 3 months postoperation. EI values at GTI and GI were significantly higher than those at MG at 6 weeks and 3 months postoperation, while there was no significant difference in the EI value between GTI and GI. At 6 months postoperation, the EI value at GI was significantly higher than those at MG. At 12 months postoperation, the EI value at GI was significantly higher than those at MG and GTI; however, there was no significant difference between GTI and MG. The EI values at GTI and MG peaked at 3 months and 6 months postoperation, respectively, and then plateaued at 12 months postoperation. However, there was no significant difference in the EI value among the different postoperative timepoints at GI. The EI value did not correlate with the VAS and ASES, UCLA scores at any time point or any postoperative observation location.

Conclusion

Revascularization of the fascia lata was dependent on the location of the fascia lata and plateaus at 12 months postoperation. The EI value did not correlate with the VAS and ASES, UCLA scores during12 months postoperation.

[Short-term safety and effectiveness of domestic polyether-ether-ketone suture anchors for rotator cuff repair: A multicenter, randomized, single-blind, parallel-controlled noninferiority study]

OBJECTIVE

A multicenter, randomized, single-blind, parallel-controlled noninferiority study was used to evaluate the short-term safety and effectiveness of domestic polyether-ether-ketone (PEEK) suture anchor for rotator cuff repair by comparing with the imported PEEK suture anchor commonly used in clinical practice.

METHODS

A total of 59 patients with rotator cuff tears who were admitted between May 2019 and October 2019 were selected as the research objects. Among them, 3 patients were excluded because they did not meet the selection criteria, and 1 patient withdrew from the study because of serious adverse events. A total of 55 patients were included in the study. They were randomly divided into trial group ( n=27) and control group ( n=28). The trial group used PEEK suture anchors produced from REJOIN Company, and the control group used PEEK suture anchors from American Arthrex Company. Two patients in control group were lost to follow-up. Twenty-seven patients in trial group and 26 patients in control group were included in the final quantitative analysis. There was no significant difference ( P>0.05) in gender, age, disease duration, side and sizes of rotator cuff tears, composition ratio of patients with type 2 diabetes, and preoperative American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score, University of California at Los Angeles (UCLA) score, and visual analogue scale (VAS) score. The patients were followed up regularly after operation. The postoperative follow-up included safety evaluation (complications, anchor position, and anchor bone reaction) and effectiveness evaluation (shoulder joint function and pain scores, rotator cuff integrity based on Sugaya classification criteria).

RESULTS

The operations in both groups were successfully completed, and there was no complication related to the operation and suture anchor. All incisions healed by first intention. There was no significant difference in follow-up time between trial group [(5.85±0.77) months] and control group [(5.96±0.72) months] ( t=0.535, P=0.595). MRI examination indicated that the repaired tendons were fixed and the anchors did not get loose or torn. At 1 day, 3 months, and 6 months after operation, there was no patient with grade 3-4 anchor bone reaction in the two groups, and there was no significant difference in the bone reaction grading between groups ( P>0.05). After operation, the VAS scores of the two groups gradually decreased, and the ASES scores, Constant-Murley scores, and UCLA scores gradually increased, and there were significant differences between groups at each time point ( P<0.05). There was no significant difference between groups at different time points ( P>0.05). There was no significant difference in Sugaya classification of rotator cuff integrity at 1 day, 3 months, and 6 months after operation between groups ( P>0.05).

CONCLUSION

The short-term safety and effectiveness of domestic PEEK suture anchors in rotator cuff tear repair are not significant different from those of imported PEEK suture anchors commonly used in clinical practice.

Clinical outcomes of reverse shoulder arthroplasty and rotator cuff repair in patients with massive rotator cuff tears without osteoarthritis: comparison using propensity score matching

BACKGROUND

The optimal management for massive rotator cuff tears (MRCTs) without osteoarthritis (OA) remains controversial. The purpose of this study was to evaluate and compare the clinical outcomes of reverse shoulder arthroplasty (RSA) vs. rotator cuff repair (RCR) in patients with MRCTs without OA.

METHODS

We conducted a retrospective data analysis of 68 patients treated for MRCTs via RSA and 215 patients treated for MRCTs via arthroscopic RCR between January 2014 and April 2019. Through propensity score matching, patients were matched for sex, age, tear size, and global fatty degeneration index. Thirty-nine patients in each group were included, and all patients had completed minimal 2-year follow-up. Postoperative radiologic evaluations of healing failure were performed. The visual analog scale score for pain, range of motion, and functional outcome measures including the American Shoulder and Elbow Surgeons score, QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score, Simple Shoulder Test score, and Constant score were assessed and compared between the 2 groups.

RESULTS

Healing failure was observed in 10 patients in the RCR group (32.3%). No statistically significant differences in preoperative range of motion and functional scores were found between the RCR and RSA groups. Both groups showed significant pain relief and functional improvement at final follow-up. Patients in the RCR group showed significantly greater forward elevation (156.4° ± 23.8° vs. 139.7° ± 22.4°, P < .001) and internal rotation (thoracic vertebra, T8.2 ± 1.2 vs. T9.7 ± 2.6, P = .001). The average American Shoulder and Elbow Surgeons score was 88.3 ± 12.2 in the RCR group and 81.8 ± 16.1 in the RSA group (P = .045). The QuickDASH score was significantly higher in the RCR group (P = .019). A significantly higher Simple Shoulder Test score (9.7 ± 2.8 vs. 8.1 ± 3.0, P = .01) and a significantly higher Constant score (67.2 ± 6.5 vs. 63.2 ± 7.1, P = .011) were seen in the RCR group.

CONCLUSION

Both RSA and RCR are effective and reliable treatment options for MRCTs without OA. However, the RCR group showed better shoulder function improvement than the RSA group. Considering the possible implications of RSA, RCR should be referred to as a first-line treatment option for patients with MRCTs without OA with proper indications.

[Evaluation methods of postoperative healing of supraspinatus tendon tear]

OBJECTIVE

To summarize the evaluation methods of postoperative healing of supraspinatus tendon tear in recent years, in order to provide reference for clinic.

METHODS

CNKI, Wanfang, PubMed, and Foreign Medical Literature Retrieval Service (FMRS) databases were used to search the literatures between 2005 and 2022. The literature related to the diagnosis and postoperative healing of supraspinatus tendon tear was included. Finally, 50 articles were reviewed.

RESULTS

Supraspinatus tendon tear is a common shoulder disease. Physical examination, clinical score, and imaging examination are used to predict and evaluate the postoperative healing. Among them, physical examination and clinical score are non-invasive and the most economical methods, but their accuracy and sensitivity are lower than imaging examination, so they can only be used as auxiliary methods. The acromio-humeral distance (AHD) and upward migration index (UMI) measured by X-ray films can directly reflect the change of supraspinatus tendon thickness, but they are impossible to distinguish whether there is tear or not. Ultrasound and MRI are the main methods for the clinical diagnosis of supraspinatus tendon tear, but the commonly used MRI sequence can not accurately judge the internal healing of the tendon. Shear wave elastrography (SWE) and ultrashort-echo-time (UTE) techniques are the latest research directions in recent years, but different studies have shown opposite conclusions on the application of SWE technique. This conclusion shows that the principle of SWE technique and its relationship with tendons need to be further studied. UTE technique has good clinical effect, and the T2* value obtained by UTE technique is more accurate than that of traditional Sugaya typing, but there are still few research samples.

CONCLUSION

AHD and UMI measured by X-ray film and T2* value measured by UTE technique can be used as effective methods for evaluating the healing of supraspinatus tendon tear after repairing, and can be used as a follow-up evaluation method combined with physical examination and clinical score for patients with supraspinatus tendon tear.

Allogeneic Dermal Fibroblasts Improve Tendon-to-Bone Healing in a Rabbit Model of Chronic Rotator Cuff Tear Compared With Platelet-Rich Plasma

PURPOSE

To compare the effects of allogeneic dermal fibroblasts (ADFs) and platelet-rich plasma (PRP) on tendon-to-bone healing in a rabbit model of chronic rotator cuff tear.

METHODS

Thirty-two rabbits were divided into 4 groups (8 per group). In 2 groups, the supraspinatus tendon was detached and was left as such for 6 weeks. At 6 weeks after creating the tear model, we performed transosseous repair with 5 × 10⁶ ADFs plus fibrin injection in the left shoulder and PRP plus fibrin in the right shoulder. The relative expression of the COL1, COL3, BMP2, SCX, SOX9, and ACAN genes was assessed at 4 weeks (group A) and 12 weeks (group B) after repair. Histologic and biomechanical evaluations of tendon-to-bone healing at 12 weeks were performed with ADF injection in both shoulders in group C and PRP injection in group D.

RESULTS

At 4 weeks, COL1 and BMP2 messenger RNA expression was higher in ADF-injected shoulders (1.6 ± 0.8 and 1.0 ± 0.3, respectively) than in PRP-injected shoulders (1.0 ± 0.3 and 0.6 ± 0.3, respectively) (P = .019 and P = .013, respectively); there were no differences in all genes in ADF- and PRP-injected shoulders at 12 weeks (P > .05). Collagen continuity, orientation, and maturation of the tendon-to-bone interface were better in group C than in group D (P = .024, P = .012, and P = .013, respectively) at 12 weeks, and mean load to failure was 37.4 ± 6.2 N/kg and 24.4 ± 5.2 N/kg in group C and group D, respectively (P = .015).

CONCLUSIONS

ADFs caused higher COL1 and BMP2 expression than PRP at 4 weeks and showed better histologic and biomechanical findings at 12 weeks after rotator cuff repair of the rabbit model. ADFs enhanced healing better than PRP in the rabbit model.

CLINICAL RELEVANCE

This study could serve as a transitional study to show the effectiveness of ADFs in achieving tendon-to-bone healing after repair of chronic rotator cuff tears in humans.

Hydrogel Development for Rotator Cuff Repair

Rotator cuff tears (RCTs) are common in shoulder disease and disability. Despite significant advances in surgical repair techniques, 20–70% of patients still have postoperative rotator cuff dysfunction. These functional defects may be related to retear or rotator cuff quality deterioration due to tendon retraction and scar tissue at the repair site. As an effective delivery system, hydrogel scaffolds may improve the healing of RCTs and be a useful treatment for irreparable rotator cuff injuries. Although many studies have tested this hypothesis, most are limited to laboratory animal experiments. This review summarizes differences in hydrogel scaffold construction, active ingredients, and application methods in recent research. Efforts to determine the indications of hydrogel scaffolds (with different constructions and cargos) for various types of RCTs, as well as the effectiveness and reliability of application methods and devices, are also discussed.

Posttreatment Imaging of the Shoulder

The shoulder joint is vulnerable for injuries following trauma and in the context of sporting activities. Degenerative rotator cuff disease is also a common entity. Conservative therapy is often not indicated or does not lead to the desired success, so surgical intervention is necessary. Routine follow-ups, but also persistent complaints, delayed healing, or recurrent trauma, usually need postoperative imaging of the shoulder. The choice of the adequate imaging modality and technique is important to reach the correct diagnosis. Additionally, knowledge of the most common surgical procedures, as well as typical normal findings and expected pathologies on different imaging modalities, is crucial for the radiologist to play a relevant role in the postoperative diagnostic process. This article addresses postoperative imaging after rotator cuff repair, shoulder arthroplasty, and surgery for shoulder stabilization with an emphasis on computed tomography and magnetic resonance imaging.

Different expectations of patients and surgeons with regard to rotator cuff repair

BACKGROUND

Rotator cuff lesions are a common shoulder pathology mainly affecting patients aged >50 years. This condition is accompanied by not only pain and loss of function but also impaired quality of life and psychological stress. A frequently employed treatment option is arthroscopic repair. But expectations regarding the outcome after surgery might differ between patients and surgeons and therefore lead to dissatisfaction on both sides. The aim of this study was to document patient expectations of a planned arthroscopic rotator cuff repair and compare the results with the assessment of shoulder surgeons.

MATERIALS AND METHODS

A total of 303 patients and 25 surgeons were involved in this study. Patients with partial- or full-thickness tear of the rotator cuff scheduled for arthroscopic repair were included in this study. Preoperatively, they were asked to fill out questionnaires inquiring sociodemographic data, scores of the underlying pathology, as well as expectations regarding the operation with regard to pain relief, gain of range of motion and strength, as well as the effect on activities of daily life, work, and sports. Furthermore, 25 surgeons were surveyed on what they think their patients expected using the same standardized questions.

RESULTS

Among the patients, 43.9% considered gain of range of motion to be the most important goal after rotator cuff repair, followed by pain relief (30.6%) and gain of force (13.7%). Among the surgeons, 72% believed pain relief to be the most important for their patient followed by movement (20%) and strength (8%). When asked which parameter was the most important to achieve after operation, for patients, movement was on first place, pain second, and strength third. For shoulder specialists, the ranking was pain, movement, and strength. Surgeons significantly overrated pain relief when ranking against movement compared with their patients.

CONCLUSION

The expectations of patients regarding their operation differ from the surgeon's assessment. Whereas gaining range of motion was more important for patients, surgeons clearly voted for pain relief. Different expectations should therefore be discussed within the pretreatment interview and taken into account when planning the right therapy. This might lead to better satisfaction on both sides.

Crimped nanofiber scaffold mimicking tendon-to-bone interface for fatty-infiltrated massive rotator cuff repair

Electrospun fibers, with proven ability to promote tissue regeneration, are widely being explored for rotator cuff repairing. However, without post treatment, the microstructure of the electrospun scaffold is vastly different from that of natural extracellular matrix (ECM). Moreover, during mechanical loading, the nanofibers slip that hampers the proliferation and differentiation of migrating stem cells. Here, electrospun nanofiber scaffolds, with crimped nanofibers and welded joints to biomimic the intricate natural microstructure of tendon-to-bone insertion, were prepared using poly(ester-urethane)urea and gelatin via electrospinning and double crosslinking by a multi-bonding network densification strategy. The crimped nanofiber scaffold (CNS) features bionic tensile stress and induces chondrogenic differentiation, laying credible basis for in vivo experimentation. After repairing a rabbit massive rotator cuff tear using a CNS for 3 months, the continuous translational tendon-to-bone interface was fully regenerated, and fatty infiltration was simultaneously inhibited. Instead of micro-CT, μCT was employed to visualize the integrity and intricateness of the three-dimensional microstructure of the CNS-induced-healed tendon-to-bone interface at an ultra-high resolution of less than 1 μm. This study sheds light on the correlation between nanofiber post treatment and massive rotator cuff repair and provides a general strategy for crimped nanofiber preparation and tendon-to-bone interface imaging characterization.

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Electrospun scaffold mimicking the microstructure of ECM was fabricated.

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The translational microstructure of tendon-to-bone interface was regenerated.

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Tendon-to-bone interface was 3D visualized with resolution less than 1 μm.

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Muscle fatty infiltration was inhibited for massive rotator cuff tear.

Effect of Mechanical Stimulation Combined With Platelet-Rich Plasma on Healing of the Rotator Cuff in a Murine Model

BACKGROUND

Mechanical stimulation and platelet-rich plasma (PRP) have been shown to be beneficial for healing of the bone-tendon interface (BTI), but few studies have explored the efficacy of a combination of these applications. We investigated the effect of mechanical stimulation combined with PRP on rotator cuff repair in mice.

HYPOTHESIS

Mechanical stimulation combined with PRP can enhance BTI healing in a murine model of rotator cuff repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 160 C57BL/6 mice were used. Overall, 40 mice were used to prepare PRP, while 120 mice underwent acute supraspinatus tendon (SST) repair. The animals were randomly assigned to 4 groups: control group, mechanical stimulation group, PRP group, and mechanical stimulation combined with PRP group (combination group). At 4 and 8 weeks postoperatively, animals were sacrificed, the eyeballs were removed to collect blood, and the SST-humeral complexes were collected. Histological, biomechanical, immunological, and bone morphometric tests were performed.

RESULTS

Histologically, at 4 and 8 weeks after surgery, the area of the fibrocartilage layer at the BTI in the combination group was larger than in the other groups. The content and distribution of proteoglycans in this layer in the combination group were significantly greater than in the other groups. At 8 weeks postoperatively, trabecular number, and trabecular bone thickness of the subchondral bone area of interest at the BTI of the combination group were greater than those of the other groups, bone volume fraction of the combination group was greater than the control group. On biomechanical testing at 4 and 8 weeks after surgery, the failure load and ultimate strength of the SST-humeral complex in the combination group were higher than in the other groups. Enzyme-linked immunosorbent assay results showed that, at 4 weeks postoperatively, the serum concentrations of transforming growth factor beta 1 and platelet-derived growth factor (PDGF) in the combination group were significantly higher than in the other groups; at 8 weeks, the PDGF-AB concentration in the combination group was higher than in the control and mechanical stimulation groups.

CONCLUSION

Mechanical stimulation combined with PRP can effectively promote the early stage of healing after a rotator cuff injury.

CLINICAL RELEVANCE

These findings imply that mechanical stimulation combined with PRP can serve as a potential therapeutic strategy for rotator cuff healing.

Effects of leukocyte-rich platelet-rich plasma and leukocyte-poor platelet-rich plasma on the healing of bone-tendon interface of rotator cuff in a mice model

Platelet-rich plasma (PRP) is widely used clinically to treat tendon injuries, and often contains leukocytes. However, the debate regarding the concentration of leukocytes in PRP is still ongoing. This study aimed to evaluate the therapeutic effects of leukocyte-rich platelet-rich plasma (LR-PRP) and leukocyte-poor platelet-rich plasma (LP-PRP) on the healing of the bone-tendon interface (BTI) of the rotator cuff. A total of 102 C57BL/6 mice were used. Thirty mice were used to prepare the PRP, while 72 underwent acute supraspinatus tendon injury repair. The animals were then randomly assigned to three groups: LR-PRP, LP-PRP and control groups. The mice were euthanized at 4 and 8 weeks postoperatively, and histological, immunological and biomechanical analyses were performed. The histological results showed that the fusion effect at the bone-tendon interface at 4 and 8 weeks after surgery was greater in the PRP groups and significantly increased at 4 weeks; however, at 8 weeks, the area of the fibrocartilage layer in the LP-PRP group increased significantly. M2 macrophages were observed at the repaired insertion for all the groups at 4 weeks. At 8 weeks, M2 macrophages withdrew back to the tendon in the control group, but some M2 macrophages were retained at the repaired site in the LR-PRP and LP-PRP groups. Enzyme-linked immunoassay results showed that the concentrations of IL-1β and TNF-α in the LR-PRP group were significantly higher than those in the other groups at 4 and 8 weeks, while the concentrations of IL-1β and TNF-α in the LP-PRP group were significantly lower than those in the control group. The biomechanical properties of the BTI were significantly improved in the PRP group. Significantly higher failure load and ultimate strength were seen in the LR-PRP and LP-PRP groups than in the control group at 4 and 8 weeks postoperatively. Thus, LR-RPR can effectively enhance the early stage of bone-tendon interface healing after rotator cuff repair, and LP-PRP could enhance the later stages of healing after rotator cuff injury.

Editorial Commentary: Interposition Graft Bridging Reconstruction: Good Mid-Term Outcomes for Massive Irreparable Rotator Cuff Tears

Massive irreparable rotator cuff tears without glenohumeral arthritis are a common cause of shoulder pain and disability. Many surgical treatment options have been proposed, including debridement, partial repair, tendon transfer, superior capsule reconstruction, balloon spacer placement, bursal acromial reconstruction, and reverse shoulder arthroplasty. Interposition graft bridging reconstruction, as evidenced by the mid-term results of the current study, may also be considered, at least for now. However, let's see if this procedure will truly stand the test of time because all orthopaedic surgeons know that the one thing that ruins good results is long-term follow-up!

The Biomechanical and Histological Processes of Rerouting Biceps to Treat Chronic Irreparable Rotator Cuff Tears in a Rabbit Model

BACKGROUND

Recently, the biceps was rerouted into a newly fabricated bicipital groove for in situ superior capsular reconstruction (SCR), resulting in promising time-zero cadaveric and clinical outcomes. However, no studies have determined the in vivo biomechanical and histological processes after the biceps is transposed to a nonanatomic position.

PURPOSE

To explore the in vivo biomechanical and histological processes of the rerouting biceps tendon to treat chronic irreparable rotator cuff tears (IRCTs) in a rabbit model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 94 skeletally mature male rabbits were used to create a chronic IRCT model in the supraspinatus tendon. Then, the biceps rerouting procedures were performed in rabbits with chronic IRCT. Eighteen rabbits were sacrificed at 1, 3, 6, 9, and 12 weeks postoperatively for biomechanical testing, micro-computed tomography scanning, and histological analysis. The biomechanical and histological changes of intra- and extra-articular portions of the rerouting biceps were evaluated at each time point, with the contralateral native superior capsule (NSC) and the native biceps (NB) as controls, respectively. The morphology and bone formation of the fabricated bicipital grooves were evaluated, with native grooves as controls.

RESULTS

The intra-articular rerouting biceps tendon was progressively remodeled over time, displaying denser fibers and more mature collagen than those of the NSC, with gradual improvements in the tendon-to-bone healing interface from 6 to 12 weeks. Consequently, the failure load and stiffness of the intra-articular rerouting biceps portion increased with time and were significantly higher than those of the NSC from 9 weeks. Similarly, the extra-articular portion of the rerouting biceps progressively healed into a new bicipital groove, as demonstrated by a smaller tendon-to-bone interface from 6 to 12 weeks, resulting in greater failure load and stiffness at 9 and 12 weeks than those of the NB attachment. The newly fabricated bicipital groove showed similar morphology to that of the native groove with sufficient trabecular bone formed underneath.

CONCLUSION

The rerouting biceps could progressively remodel and heal into the newly fabricated bicipital groove over time, resulting in greater biomechanical performances in intra- and extra-articular portions than the NSC and the NB attachment.

CLINICAL RELEVANCE

The biceps rerouting technique may be a feasible procedure to perform in situ SCR to treat IRCT in the future clinical practice; however, more clinical evidence is required.