When do rotator cuff repairs fail? Serial ultrasound examination after arthroscopic repair of large and massive rotator cuff tears

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

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

Novel methods to diagnose rotator cuff tear and predict post-operative Re-tear: Radiomics models

Objective

To validated a classifier to distinguish the status of rotator cuff tear and predict post-operative re-tear by utilizing magnetic resonance imaging (MRI) markers.

Methods

This retrospective study included patients with healthy rotator cuff and patients diagnosed as rotator cuff tear (RCT) by MRI. Radiomics features were identified from the pre-operative shoulder MRI and selected by using maximum relevance minimum redundancy (MRMR) methods. A radiomics model for diagnosis of RCT was constructed, based on the 3D volume of interest (VOI) of supraspinatus. Another model for the prediction of rotator re-tear after rotator cuff repair (Re-RCT) was constructed based on VOI of humerus, supraspinatus, infraspinatus and other clinical parameters.

Results

The model for diagnosing the status of RCT produced an area under the receiver operating characteristic curve (AUC) of 0.989 in the training cohort and 0.979 for the validation cohort. The radiomics model for predicting Re-RCT produced an AUC of 0.923 ± 0.017 for the training dataset and 0.790 ± 0.082 for the validation dataset. The nomogram combining radiomics features and clinical factors yielded an AUC of 0.961 ± 0.020 for the training dataset and 0.808 ± 0.081 for the validation dataset, which displayed the best performance among all models.

Conclusion

Radiomics models for the diagnosis of rotator cuff tear and prediction of post-operative Re-RCT yielded a decent prediction accuracy.

Augmentation of a Transosseous-Equivalent Repair in Posterosuperior Nonacute Rotator Cuff Tears With a Bioinductive Collagen Implant Decreases the Retear Rate at 1 Year: A Randomized Controlled Trial

PURPOSE

To determine whether the addition of a bioinductive collagen implant (BCI) over a transosseous equivalent (TOE) repair of medium-to-large posterosuperior rotator cuff tears improves the healing rate determined by magnetic resonance imaging (MRI) at 12-month follow-up.

METHODS

A Level I randomized controlled trial was performed in 124 subjects with isolated, symptomatic, reparable, full-thickness, medium-to-large posterosuperior nonacute rotator cuff tears, with fatty infiltration ≤2. These were randomized to 2 groups in which an arthroscopic posterosuperior rotator cuff tear TOE repair was performed alone (Control group) or with BCI applied over the TOE repair (BCI group). The primary outcome was the retear rate (defined as Sugaya 4-5) determined by MRI at 12 months of follow-up. Secondary outcomes were characteristics of the tendon (Sugaya grade and thickness of the healed tendon) and clinical outcomes (pain levels, EQ-5D-5L, American Shoulder and Elbow Surgeons, and Constant-Murley scores) at 12 months of follow-up.

RESULTS

Of the 124 randomized patients, 122 (60 in the BCI group and 62 in the Control group) were available for MRI evaluation 12.2 ± 1.02 months after the intervention. There were no relevant differences in preoperative characteristics. Adding the BCI reduced the retear rate (8.3% [5/60] in the BCI group vs 25.8% [16/62] in the Control group, P = .010; relative risk of retear of 0.32 [95% confidence interval 0.13-0.83]). Sugaya grade was also better in the BCI group (P = .030). There were no differences between groups in the percentage of subjects who reached the MCID for CMS (76.7% vs 81.7%, P = .654) or American Shoulder and Elbow Surgeons (75% vs 80%, P = .829), in other clinical outcomes or in complication rates at 12.4 ± 0.73 (range 11.5-17) months of follow-up.

CONCLUSIONS

Augmentation with a BCI of a TOE repair in a medium-to-large posterosuperior rotator cuff tear reduces the retear rate at 12-month follow-up by two-thirds, yielding similar improvements in clinical outcomes and without increased complication rates.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

The effect of rehabilitation time on functional recovery after arthroscopic rotator cuff repair: a systematic review and meta-analysis

Objective

We compared the effects of early and delayed rehabilitation on the function of patients after rotator cuff repair by meta-analysis to find effective interventions to promote the recovery of shoulder function.

Methods

This meta-analysis was registered in PROSPERO (CRD42023466122). We manually searched the randomized controlled trials (RCTs) in the Cochrane Library, Pubmed, Cochrane Library, EMBASE, the China National Knowledge Infrastructure (CNKI), the China VIP Database (VIP), and the Wanfang Database to evaluate the effect of early and delayed rehabilitation after arthroscopic shoulder cuff surgery on the recovery of shoulder joint function. Review Manager 5.3 software was used to analyze the extracted data. Then, the PEDro scale was employed to appraise the methodological quality of the included research.

Results

This research comprised nine RCTs and 830 patients with rotator cuff injuries. According to the findings of the meta-analysis, there was no discernible difference between the early rehabilitation group and the delayed rehabilitation group at six and twelve months after the surgery in terms of the VAS score, SST score, follow-up rotator cuff healing rate, and the rotator cuff retear rate at the final follow-up. There was no difference in the ASES score between the early and delayed rehabilitation groups six months after the operation. However, although the ASES score in the early rehabilitation group differed significantly from that in the delayed rehabilitation group twelve months after the operation, according to the analysis of the minimal clinically important difference (MCID), the results have no clinical significance.

Conclusions

The improvement in shoulder function following arthroscopic rotator cuff surgery does not differ clinically between early and delayed rehabilitation. When implementing rehabilitation following rotator cuff repair, it is essential to consider the paradoxes surrounding shoulder range of motion and tendon anatomic healing. A program that allows for flexible progression based on the patient's ability to meet predetermined clinical goals or criteria may be a better option.

Effect of Porcine-Derived Absorbable Patch-Type Atelocollagen for Arthroscopic Rotator Cuff Repair: A Prospective Randomized Controlled Trial

BACKGROUND

Even though arthroscopic rotator cuff repair is recognized as a standard treatment option, the risk of postoperative retear is a major concern.

PURPOSE

To evaluate the effect of porcine-derived absorbable patch-type atelocollagen during arthroscopic rotator cuff repair.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 64 patients with rotator cuff tears diagnosed on magnetic resonance imaging (MRI) were enrolled prospectively from November 2020 to December 2021. Both groups had repairs using the suture bridge technique. For the atelocollagen group, before securing the lateral anchors, we inserted porcine-derived absorbable patch-type atelocollagen between the footprint and the tendon. On postoperative day 2, the patients underwent MRI to confirm containment of the patch-type atelocollagen. At 6 months and 1 year postoperatively, the signal intensity of the repaired tendon was assessed using MRI. Patients were evaluated using the Constant score as the primary outcome, along with the visual analog scale for pain; range of motion; American Shoulder and Elbow Surgeons score; University of California, Los Angeles, score; and Korean Shoulder Score preoperatively and at 2, 3, 6, and 12 months postoperatively.

RESULTS

No significant changes in the Constant score as primary outcome, pain or other functional scores, and range of motion were observed between the groups at 1 year postoperatively. The patch-type atelocollagen was confirmed to be contained by the time-zero MRI scan taken 2 days postoperatively. Among the 55 patients included in final analysis, 12 retear cases were recorded (21.8% retear rate). A significantly lower retear rate was found in the atelocollagen group, as 3 cases were observed in this group (10.3%) and 9 cases were observed in the conventional repair group (34.6%) (P = .048).

CONCLUSION

The Constant score was not different between the groups. The retear rate after rotator cuff repair was significantly lower in the group that received porcine-derived absorbable patch-type atelocollagen compared with in the conventional group.

REGISTRATION

KCT0005184 (Clinical Research Information Service [CRIS]; https://cris.nih.go.kr).

Are Lower Passive Anterior Elevation and External Rotation at 6 Weeks Postoperatively Associated With Healing of Isolated Arthroscopic Supraspinatus Repairs?

BACKGROUND

Despite advancements in surgical technique, failure of tendon healing remains a common problem after arthroscopic rotator cuff repair (ARCR).

PURPOSE/HYPOTHESIS

The purpose of this study was to examine the relationship between range of motion (ROM) recovery and healing after ARCR. It was hypothesized that an early loss of ROM would be associated with tendon healing.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

This was a retrospective comparative study of primary ARCR of isolated full-thickness supraspinatus (SSN) tendon tears. Cases were retrieved from a prospective rotator cuff repair database and divided into 2 groups based on healing (healed/nonhealed). A standardized clinical evaluation was performed before and at 6 weeks, 3 months, and 6 months after surgery. Collected data included passive and active ROM, visual analog scale for pain, and Constant score. Healing was assessed by ultrasound at 6 months.

RESULTS

Of 1397 eligible ARCRs, 1207 were included. The healing rate was 86.7%. Age was higher in the nonhealed group (57.8 ± 7.9 years vs 61.6 ± 8.8 years; P < .001). Patients with healed repairs had a larger decrease in passive anterior elevation (AE) from the preoperative to the 6-week postoperative visit (-31°± 28° vs -18°± 26°; P < .001), followed by a more substantial increase throughout the remaining follow-up period (32°± 23° vs 18°± 21°; P < .001). At 6 months postoperatively, there was no difference in AE between groups (159°± 17° vs 161°± 14°; P > .999). External rotation elbow at side (ER1) and internal rotation hand in the back (IR1) followed similar courses of recovery. Passive and active ROM had a strong positive correlation at each follow-up. Age (odds ratio [OR], 1.79; 95% CI, 1.45-2.23; P < .001) and 6-week passive AE (OR, 1.33; 95% CI, 1.20-1.48; P < .001) and ER1 (OR, 1.15; 95% CI, 1.03-1.29; P = .017) were predictors for nonhealing.

CONCLUSION

Lower passive AE and ER1 at 6 weeks postoperatively and younger age are associated with healing after ARCR of isolated SSN tendon tears. At 6 months postoperatively, there were no differences in ROM, regardless of tendon healing.

A Systematic Review and Meta-analysis of Risk Factors for the Increased Incidence of Revision Surgery After Arthroscopic Rotator Cuff Repair

BACKGROUND

Approximately 90% of patients who undergo arthroscopic rotator cuff repair (RCR) are satisfied with their pain levels and function after surgery. However, a subset of patients experience continued symptoms that warrant revision surgery. Preoperative risk factors for RCR failure requiring revision surgery have not been clearly defined.

PURPOSE

To (1) determine the rate of RCR failure requiring revision surgery and (2) identify risk factors for revision surgery, which will help surgeons to determine patients who are at the greatest risk for RCR failure.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

A systematic review and meta-analysis in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were performed. The initial search resulted in 3158 titles, and 533 full-text articles were assessed for eligibility. A total of 10 studies met the following inclusion criteria: (1) human clinical studies, (2) arthroscopic RCR, (3) original clinical research, and (4) evaluation of preoperative risk factors for revision.

RESULTS

After a full-text review, a total of 16 risk factors were recorded and analyzed across 10 studies. Corticosteroid injection was the most consistent risk factor for revision surgery, reaching statistical significance in 4 of 4 studies, followed by workers' compensation status (2/3 studies). Patients with corticosteroid injections had a pooled increased risk of revision surgery by 47% (odds ratio, 1.44 [95% CI, 1.36-1.52]). Patients with workers' compensation had a pooled increased risk of revision surgery by 133% (odds ratio, 2.33 [95% CI, 2.09-2.60]). Age, smoking status, diabetes, and obesity were found to be risk factors in half of the analyzed studies.

CONCLUSION

Corticosteroid injections, regardless of the frequency of injections, and workers' compensation status were found to be significant risk factors across the literature based on qualitative analysis and pooled analysis. Surgeons should determine ideal candidates for arthroscopic RCR by accounting for corticosteroid injection history, regardless of the frequency, and insurance status of the patient.

Rotator Cuff Repair With Patch Augmentation Is Associated With Lower Retear Rates for Large Tears: A Systematic Review of Randomized Controlled Trials

PURPOSE

To perform a systematic review of randomized controlled trials comparing clinical outcomes of rotator cuff repair with and without patch augmentation.

METHODS

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, the Cochrane Library, and Embase to identify randomized controlled trials that directly compared outcomes between rotator cuff repair (RCR) with versus without patch augmentation. Patients were evaluated based on retear rate, histological outcomes, radiological outcomes, and patient-reported outcomes (Constant score; American Shoulder and Elbow Surgeons [ASES] score; University of California-Los Angeles shoulder scale; Simple Shoulder Test; EuroQol-visual analog scale; Disabilities of the Arm, Shoulder and Hand score; and PENN shoulder score questionnaire).

RESULTS

Six studies (1 level I, 5 level II) met inclusion criteria, including 188 patients undergoing RCR alone (Control) and 193 patients undergoing RCR with patch augmentation (Patch). Patient age ranged from 56.0 to 68.0 years. The mean follow-up time ranged from 14.0 to 68.4 months. The average body mass index ranged from 24.4 to 29.4, and the overall percentage of males ranged from 32.5% to 82.3%. Three studies found significantly decreased retear rates with patch augmentation. The retear rate ranged from 34.0% to 65.4% in the Control group and 9.1% to 52.9% in the Patch group. One study found a significant difference for the Constant score favoring the Patch group. Two studies found a significant difference for the ASES score favoring the Patch group. One study found significantly better results with patch augmentation in terms of repaired tendon thickness and footprint coverage, based on magnetic resonance imaging.

CONCLUSIONS

Patch augmentation of rotator cuff repairs may be associated with lower retear rates for large tears. There is limited evidence to suggest that patch augmentation is associated with improved patient-reported outcomes.

LEVEL OF EVIDENCE

Level II, systematic review of level I and II studies.

Which is better? Early versus delayed rehabilitation after arthroscopic rotator cuff repair

PURPOSE

This study aimed to compare the 5-year clinical and functional outcomes, including repaired tendon healing status, between early and delayed rehabilitation after arthroscopic rotator cuff repair METHODS: A total of 75 patients with rotator cuff tears (less than 5 cm) underwent arthroscopic repairs over a 60-month period. Participants were randomly assigned to early and delayed postoperative rehabilitation groups with distinct protocols. Clinical and functional outcome measures included Constant score, University of California at Los Angeles (UCLA) score, visual analogue scale for pain and isokinetic dynamometer test for muscle strength recovery. Clinical and functional scores were compared between baseline and 5 years postoperatively. Radiologic assessment via magnetic resonance imaging was performed at a minimum of 12 months postoperatively for evaluations of tendon integrity and recurrent tears.

RESULTS

Baseline characteristics showed no statistically significant differences between groups. Both groups demonstrated equivalent improvement in range of motion and pain scores with no statistical differences. Clinical scores improved significantly in both groups by postoperative 12 months and plateaued. At the postoperative 5-year mark, the early group showed better improvement in the visual analogue scale and UCLA score, while the delayed group had superior Constant scores. Postoperative magnetic resonance imaging revealed six recurrent tears, two in the early group and four in the delayed group, with no statistical differences. Muscle strength recovery showed no differences between the two groups.

CONCLUSION

Both the early and the delayed rehabilitation groups showed similar outcomes in postoperative range of motion, functional scores, muscle strength recovery and tendon healing in the short- and mid-term follow-ups.

LEVEL OF EVIDENCE

Level III.

One- and 2-Year American Shoulder and Elbow Surgeons Scores Do Not Vary Significantly After Arthroscopic Rotator Cuff Repair: A Prospective Multicenter Analysis of 1,567 Patients

PURPOSE

To evaluate whether there are clinically significant changes in patient-reported outcomes between 1 and 2 years' postoperatively after arthroscopic rotator cuff repair (RCR).

METHODS

A retrospective analysis of prospective, multicenter registry was queried for all patients who underwent RCR. Patients with preoperative, 6-month, 1-year, and 2-year postoperative American Shoulder and Elbow Surgeons (ASES) scores were included. We evaluated mean postoperative ASES scores, Δ (change from preoperative) ASES, and the %MOI (% maximum outcome improvement). We also evaluated achievement of clinically significant outcomes (CSOs) for the ASES score, including the minimal clinically important difference (MCID), substantial clinical benefit, and patient-acceptable symptom state.

RESULTS

There were 1,567 patients with complete data through 2-year follow-up. There were small differences in achievement of CSOs from 1 to 2 years: 88% to 91% for MCID, 81% to 83% for substantial clinical benefit, and 65% to 71% for patient-acceptable symptom state. There were statistically significant differences from 1 to 2 years in mean ASES (87 to 88, P < .001), Δ ASES (37 to 39, P < .001), and %MOI (72% to 76%, P < .001); however, these changes were well below the MCID of 11.1. From 1 to 2 years, the mean ASES improved only 1.7 points (P < .001). At 1 year, patients achieved, on average, 97% of their 2-year ASES.

CONCLUSIONS

Both patient-reported outcomes and achievement of CSOs show small differences at 1 and 2 years after RCR. Given the large sample size, there were statistical differences, but these are unlikely to be clinically relevant.

LEVEL OF EVIDENCE

Level IV, case series.

Dyslipidemia may impact initial recovery following arthroscopic rotator cuff repair: a retrospective study

BACKGROUND

The current literature shows that dyslipidemia can lead to a higher incidence of rotator cuff tears (RCTs) and an increased retear rate after repair. We aimed to evaluate the influence of preoperative dyslipidemia on postoperative pain, patient-reported outcomes (PROs), active range of motion (ROM), and structural integrity.

METHODS

A cohort of 111 patients who underwent arthroscopic RCT repair between January 2021 and July 2022, and whose complete preoperative serum lipid data were available within one week prior to surgery was retrospectively reviewed. Dyslipidemia was defined as the presence of an increase or decrease in at least one blood lipid profile (triglycerides, total cholesterol, low-density lipoprotein, high-density lipoprotein, or non-high-density lipoprotein). There were 43 patients in the dyslipidemia group and 68 in the ortholiposis group. Patient evaluations, including pain score, PROs, and ROMs, were conducted preoperatively; at 3 and 6 months postoperatively; and at the last follow-up. Structural integrity was assessed by magnetic resonance imaging (MRI) 6 months after surgery if possible, and Sugaya type 4 or 5 was considered a retear. Propensity score matching (PSM) was used to reduce bias.

RESULTS

The RCT size, surgical technique, preoperative pain status, PROs, and active ROM were comparable between patients with dyslipidemia and those with ortholiposis. Three months after surgery, patients in the dyslipidemia group had worse average PROs (Constant score: P = 0.001; ASES score: P = 0.012; UCLA score: P = 0.015), forward flexion (P = 0.012), and internal rotation (P = 0.001) than patients in the ortholiposis group did. The difference between the two groups persisted after PSM but disappeared at the sixth month after surgery. No significant differences in pain score, PROs, or active ROMs were detected between the dyslipidemia and ortholiposis groups after a mean follow-up of 24 months. Of the 72 patients who underwent MRI, 4 retears (5.6%) were found, and all were in the ortholiposis group. There was no difference in the rate of retears between the two groups (P = 0.291) or with (P = 0.495) PSM.

CONCLUSIONS

In conclusion, we found that perioperative dyslipidemia may impact initial recovery within the first 3 months following arthroscopic rotator cuff repair but may have no effect on pain, PROs, or active ROMs at a mean 2-year follow-up or rotator cuff integrity at 6 months postoperatively. Trail registration Retrospectively registered.

The Fate of the Shoulder Post Rotator Cuff Repair: Biomechanical Properties of the Supraspinatus Tendon and Surrounding Structures

The study aimed to describe the changes in biomechanical properties of the supraspinatus tendon, deltoid muscle, and humeral head post arthroscopic rotator cuff repair using shear wave elastography. Shear wave velocity of the tendon, deltoid, and humeral head of 48 patients was measured at predetermined sites at 1 week, 6 weeks, 12 weeks, 6 months, and 12 months post repair. One-way ANOVA with Tukey's correction and Spearman's correlation were performed. Mean±SEM healing tendon stiffness, adjacent to tendon footprint, increased from 1 week (6.2±0.2 m/s) to 6 months (7.5±0.3 m/s) and 12 months (7.8±0.3 m/s) (P<0.001). Mean±SEM deltoid muscle stiffness was higher at 12 months (4.1±0.2 m/s) compared to 1 week (3.4±0.1 m/s) and 12 weeks (3.5±0.1 m/s) (P<0.05). Humeral head stiffness did not change. Following arthroscopic rotator cuff repair, supraspinatus tendon stiffness increased in a curvilinear fashion over 6 months. From 6 months, deltoid muscle stiffness increased, corresponding to when patients were instructed to return to normal activities.

Early Postoperative Stiffness After Arthroscopic Rotator Cuff Repair Correlates With Improved Tendon Healing

PURPOSE

To assess whether early postoperative stiffness predicts long-term stiffness and its relationship with repair integrity in patients who undergo arthroscopic rotator cuff repair (ARCR).

METHODS

This was a single-center retrospective study; 427 patients undergoing primary ARCR by a board-certified orthopaedic surgeon over 4 years were considered. Patients with at least 1 year of follow-up were categorized into stiff and non-stiff groups based on their range of motion (ROM) at 3 months' postoperatively. Stiffness was defined as passive forward flexion <120°, external rotation <30°, or internal rotation below L3. We evaluated clinical outcomes using demographics, ROM, Constant Shoulder (CS) score, University of California, Los Angeles (UCLA) score, and visual analog scale (VAS) for pain preoperatively and at 3, 6, and 12 months' postoperatively. Stiffness, retear rates, and tendon integrity were assessed via magnetic resonance imaging at 12 months.

RESULTS

Of 155 patients meeting the inclusion criteria, 68 (43.9%) were stiff, and 87 (56.1%) were non-stiff. The stiff group had significantly lower preoperative CS and UCLA scores (P = .013/.014) and greater VAS score (P = .034). At 3 months, this group showed lower ROM and functional scores (P < .001), persisting at 6 and 12 months (except internal rotation) (P < .001). Their 12-month VAS score was greater (P = .024). Postoperative stiffness occurred in 10.3% of the stiff group and 2.3% of the non-stiff group (P = .035). The 12-month retear rate was 5.9% in the stiff group and 17.2% in the non-stiff group (P = .032). Minimal clinically important difference analysis indicated ROM changes but limited functional score changes in the 2 groups.

CONCLUSIONS

This study showed that early postoperative shoulder stiffness correlates with lower preoperative functional scores and greater pain levels. Shoulder stiffness at 3 months' post-ARCR predicts 12-month shoulder stiffness but indicates better tendon integrity. While early stiffness is linked to lower functional scores and more pain, its long-term clinical impact seems limited.

LEVEL OF EVIDENCE

Level III, retrospective comparison study.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

Top 50 most impactful publications on massive rotator cuff tears

Background

Bibliometric analysis is a useful tool for measuring the scholarly impact of a topic and its more and less heavily studied aspects. The purpose of this study is to use bibliometric analysis to comprehensively analyze the 50 articles with the highest citation indices in studies evaluating the treatment and outcomes of massive rotator cuff tears (mRCTs).

Methods

This cross-sectional study identified articles within the Scopus database published through December 2022. Keywords used were "massive rotator cuff tear." Articles were sorted in chronological order. The year published and number of citations were recorded. A citation index (CI) was calculated for each article by dividing the number of citations by number of years published [1 citation/1 year published (2021) = CI of 1]. Of these, the 50 articles with the highest CIs were carried forward for evaluation. Frequencies and distributions were assessed for data of each variable collected.

Results

These search methods produced 625 articles regarding mRCT research (ranging from January 1986 to December 2022). Four of the top 10 most impactful articles were published in the 2010s. The level of evidence (LOE) published with the greatest frequency was level of evidence 4 (41%). The journal Arthroscopy published the highest number within the top 50 (26%) followed by the Journal of Bone and Joint Surgery and the American Journal of Sports Medicine (20% each). Clinical studies composed 88% of the top 50. Case series (38%) predominated, while systematic reviews (20%) and randomized control trials (8%) were less prevalent. The majority of studies concentrated on the clinical outcomes of certain interventions (62%), mainly comparing multiple interventions.

Conclusion

Despite the relatively high prevalence of mRCTs (40% of all tears), this topic comprises only a small proportion of all rotator cuff research. This analysis has identified gaps within and limitations of the findings concerning mRCTs for researchers to propose research questions targeting understudied topics and influence the future treatment and outcomes of this clinically difficult diagnosis.

Repair of chronic and large rotator cuff tears using extra-synovial autografts: An experimental study in rabbits

Purpose

To investigate whether and how extra-synovial autografts can enhance the reconstruction of chronic and large rotator cuff tears in a rabbit subscapularis model.

Methods

Twenty rabbits were used to create a large subscapularis tear bilaterally. Six weeks later, the right shoulder of each rabbit was operated to repair the tear with an extra-synovial autograft, whereas the left shoulder did not undergo any surgery. At 6 and 12 weeks after the second procedure, the specimens underwent biomechanical and histological evaluation. Six more rabbits were used only as a normal reference.

Results

Biomechanical evaluation demonstrated that the ultimate load to failure of the Graft group (184.1 ± 35.7 N) was significantly higher (p = 0.04) than that of the Defect group (144.5 ± 32.2 N) at 12 weeks after repair, rising to 76% of the normal subscapularis tendon tensile strength. Histological analysis revealed an enhanced healing environment with neoangiogenesis and decreased inflammatory response at the repair site. Moreover, the tendon maturing score of the Graft group increased substantially from 6 (15.8 ± 0.9) to 12 (23.1 ± 0.6) weeks after repair (p = 0.01).

Conclusion

In vivo data support the efficacy of extra-synovial autograft interposition in repairing chronic and large rotator cuff tears in a rabbit subscapularis model. The autografts were capable of enhancing the biomechanical properties of the repaired tendons, as evidenced by increased tensile strength, and forming new connective tissue simulating a fibrocartilage zone, as revealed by histological evaluation.

Level of Evidence

N/A.

Hedgehog Activation for Enhanced Rotator Cuff Tendon-to-Bone Healing

BACKGROUND

Rotator cuff repair is a common orthopaedic procedure, yet the rate of failure to heal after surgery is high. Repair site rupture is due to poor tendon-to-bone healing and lack of regeneration of the native fibrocartilaginous enthesis. During development, the enthesis is formed and mineralized by a pool of progenitors activated by hedgehog signaling. Furthermore, hedgehog signaling drives regenerative enthesis healing in young animals, in contrast to older animals, in which enthesis injuries heal via fibrovascular scar and without participation of hedgehog signaling.

HYPOTHESIS

Hedgehog activation improves tendon-to-bone healing in an animal model of rotator cuff repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 78 adult Sprague-Dawley rats were used. Supraspinatus tendon injury and repair were completed bilaterally, with microsphere-encapsulated hedgehog agonist administered to right shoulders and control microspheres administered to left shoulders. Animals were sacrificed after 3, 14, 28, or 56 days. Gene expression and histological, biomechanical, and bone morphometric analyses were conducted.

RESULTS

At 3 days, hedgehog signaling pathway genes Gli1 (1.70; P = .029) and Smo (2.06; P = .0173), as well as Runx2 (1.69; P = .0386), a transcription factor of osteogenesis, were upregulated in treated relative to control repairs. At 14 days, transcription factors of tenogenesis, Scx (4.00; P = .041), and chondrogenesis, Sox9 (2.95; P = .010), and mineralized fibrocartilage genes Col2 (3.18; P = .031) and Colx (1.85; P = .006), were upregulated in treated relative to control repairs. Treatment promoted fibrocartilage formation at the healing interface by 28 days, with improvements in tendon-bone maturity, organization, and continuity. Treatment led to improved biomechanical properties. The material property strength (2.43 vs 1.89 N/m2; P = .046) and the structural property work to failure (29.01 vs 18.09 mJ; P = .030) were increased in treated relative to control repairs at 28 days and 56 days, respectively. Treatment had a marginal effect on bone morphometry underlying the repair. Trabecular thickness (0.08 vs 0.07 mm; P = .035) was increased at 28 days.

CONCLUSION

Hedgehog agonist treatment activated hedgehog signaling at the tendon-to-bone repair site and prompted increased mineralized fibrocartilage production. This extracellular matrix production and mineralization resulted in improved biomechanical properties, demonstrating the therapeutic potential of hedgehog agonism for improving tendon-to-bone healing after rotator cuff repair.

CLINICAL RELEVANCE

This study demonstrates the therapeutic potential of hedgehog agonist treatment for improving tendon-to-bone healing after rotator cuff injury and repair.

Types and doses of anti-adhesive agents injected into subacromial space do not have an effect on the clinical and anatomical outcomes after arthroscopic rotator cuff repair

PURPOSE

Joint stiffness after arthroscopic rotator cuff repair is a major concern for orthopaedic surgeons. Various antiadhesive agents are commonly administered after rotator cuff repair for its prevention. This study aimed to compare the outcomes among patients injected with different types and amounts of anti-adhesive agents after rotator cuff repair. It was hypothesized that the outcomes might differ depending on the use of the anti-adhesive agent and its type and dose.

METHODS

A total of 267 patients who underwent arthroscopic rotator cuff repair with or without subacromial injection of anti-adhesive agents were enrolled. The first group (group A; 51 patients) were injected with 3 mL of poloxamer/sodium alginate-based anti-adhesive agent. The second group (group B; 93 patients) were injected with 3 mL of sodium hyaluronate-based anti-adhesive agent. The third group (group C; 82 patients) were injected with 1.5 mL of sodium hyaluronate-based anti-adhesive agent. Finally, the last group (group D; 41 patients) who did not use anti-adhesive agents served as the control. The range of motion (ROM) and pain VAS scores were measured preoperatively and at 5 weeks, 3 months, 6 months, and 1 year postoperatively. Functional outcomes were evaluated using American Shoulder and Elbow Surgeons and Constant scores, whereas cuff integrity was assessed via MRI or ultrasonography at least 6 months postoperatively.

RESULTS

All ROM measurements, pain VAS scores, and functional scores were significantly improved regardless of the use, type, and dose of the anti-adhesive agents. In addition shoulder ROM and rotator cuff healing did not significantly differ among the groups (all n.s.).

CONCLUSIONS

No significant differences were found in the clinical and anatomical outcomes according to the type and dose of the anti-adhesive agents subacromially injected after rotator cuff repair.

LEVEL OF EVIDENCE

III.

Providing safe and effective rehabilitation by assessing supraspinatus muscle elasticity using ultrasound real-time tissue elastography after rotator cuff repair: A case series

INTRODUCTION

Although surgical techniques have advanced to avoid a postoperative re-tear after rotator cuff surgery, it remains unclear how to directly evaluate the risk of a re-tear.

OBJECTIVE

To describe how muscle elasticity with real-time tissue elastography could be used to avoid re-tear in individual cases after rotator cuff repair.

CASE DESCRIPTION

This case series included four patients, two per tear size (small and large/massive), with contrasting changes in muscle elasticity of the supraspinatus muscle. All patients underwent primary arthroscopic or open rotator cuff repair. The elasticity of the supraspinatus muscle was evaluated at relaxed and elongated positions of 0° and 60° shoulder abduction angles, respectively. The change in muscle elasticity at 1 month after surgery was characteristically different, and we predicted that a greater elasticity in the elongated position indicated a higher risk of re-tear. The cases with high risk underwent careful rehabilitation to avoid re-tear, and no re-tears were recorded in this report.

CONCLUSION

Our findings suggested that evaluation of muscle elasticity using real-time tissue elastography, which provides an indication of the risk of re-tear, in the clinical setting might be useful for therapists, who could adjust the intensity of rehabilitation, and for patients.

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

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

Microfragmented adipose tissue in the treatment of a full-thickness supraspinatus tear: a case report

A 70-year-old female presented with an 8-month history of right anterior shoulder pain and weakness, unresolved with conservative management. Among other shoulder pathology, the patient was diagnosed with a full-thickness supraspinatus tear and elected to proceed with the microfragmented adipose tissue procedure to treat the injured tendon and nearby relevant structures. Improvements in pain and function were documented along with progressive healing of the supraspinatus on ultrasound and MRI following the procedure. This case demonstrates the efficacy of microfragmented adipose tissue as a relatively novel approach to treating non-retracted, full-thickness rotator cuff tears.

Prediction of Retear After Arthroscopic Rotator Cuff Repair Based on Intraoperative Arthroscopic Images Using Deep Learning

BACKGROUND

It is challenging to predict retear after arthroscopic rotator cuff repair (ARCR). The usefulness of arthroscopic intraoperative images as predictors of the ARCR prognosis has not been analyzed.

PURPOSE

To evaluate the usefulness of arthroscopic images for the prediction of retear after ARCR using deep learning (DL) algorithms.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

In total, 1394 arthroscopic intraoperative images were retrospectively obtained from 580 patients. Repaired tendon integrity was evaluated using magnetic resonance imaging performed within 2 years after surgery. Images obtained immediately after ARCR were included. We used 3 DL architectures to predict retear based on arthroscopic images. Three pretrained DL algorithms (VGG16, DenseNet, and Xception) were used for transfer learning. Training and test sets were split into 8:2. Threefold stratified validation was used to fine-tune the hyperparameters using the training data set. The validation results of each fold were evaluated. The performance of each model in the test set was evaluated in terms of accuracy, area under the receiver operating characteristic curve (AUC), F1-score, sensitivity, and specificity.

RESULTS

In total, 1138 and 256 arthroscopic images were obtained from 514 patients and 66 patients in the nonretear and retear groups, respectively. The mean validation accuracy of each model was 83% for VGG16, 89% for Xception, and 91% for DenseNet. The accuracy for the test set was 76% for VGG16, 87% for Xception, and 91% for DenseNet. The AUC was highest for DenseNet (0.92); it was 0.83 for VGG16 and 0.91 for Xception. For the test set, the specificity and sensitivity were 0.93 and 0.84 for DenseNet, 0.89 and 0.84 for Xception, and 0.70 and 0.80 for VGG16, respectively.

CONCLUSION

The application of DL algorithms to intraoperative arthroscopic images has demonstrated a high level of accuracy in predicting retear occurrences.

Microfracture Lateral to the Greater Tuberosity of the Humerus Enhances Tendon-to-Bone Healing in a Rat Rotator Cuff Model

BACKGROUND

Microfracture at the rotator cuff insertion is an established surgical marrow-stimulation technique for enhancing rotator cuff healing. However, the effect of lateralized or medialized microfracture on the insertion is unknown.

PURPOSE

To compare the biomechanical and histologic effects of microfracture at 3 different regions for rotator cuff repair in a rat model.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 72 Sprague-Dawley rats with bilateral supraspinatus tendon insertion detachment were allocated into 4 groups with 4 different interventions: no microfracture at the humeral head as a control group (Con), traditional microfracture at the footprint area (MFA), and medialized microfracture to the footprint area (MMFA) on the articular surface of the humerus or lateralized microfracture to the footprint area at the greater tuberosity (LMFA). All underwent immediate repair. Tendon-to-bone healing was assessed by biomechanical and histologic tests 4 and 8 weeks postoperation.

RESULTS

At 4 weeks, the LMFA group showed a significantly superior failure load compared with the other groups (all P < .05). The LMFA and MFA groups showed significantly superior stiffness compared with the Con and MMFA groups (all P < .01). At 8 weeks, superior failure load and stiffness were observed in the LMFA group compared with the control group (all P < .05). Histologic examination revealed that the LMFA group had superior collagen composition and tendon-to-bone maturation at the interface at 4 and 8 weeks compared with the Con group (all P < .05).

CONCLUSION

Lateralized microfracture at the greater tuberosity improved the histologic quality of repair tissue and biomechanical strength at the tendon-to-bone insertion after rotator cuff repair in a rat model.

CLINICAL RELEVANCE

Microfracture lateral to the footprint area might be a better way to enhance rotator cuff healing clinically.

Timing of retears after arthroscopic rotator cuff repair and associated factors: a retrospective analysis

BACKGROUND

Retear after arthroscopic rotator cuff repair (ARCR) remains a complication of important concern. Few reports have evaluated retear timing and its associated patient characteristics in large cohorts. This study aimed to investigate retear timing and patient characteristics and factors associated with this parameter.

METHODS

Of the 638 consecutive shoulders that underwent ARCR from August 2009 to November 2019, shoulders with retear complication within 1 year of surgery were included. Retears were defined as type IV or V of the Sugaya's classification, and magnetic resonance imaging was performed at 6 weeks, 3 months, 6 months, and 1 year after surgery. The distribution of patients with retears at the timing of retears was investigated. In addition, patients with retears were classified into the following two groups: early group with retears occurring at 6 weeks and 3 months postoperatively or late group with retears occurring between 6 months and 1 year postoperatively. Associated factors such as sex, age, tear size, pre and postoperative range of motion, surgical technique, and clinical outcome between the two groups were investigated.

RESULTS

The 41 shoulders with retears were divided into four groups: 1) within 6 weeks after surgery (n = 9, 22.0%), 2) 6 weeks-to 3 months after surgery (n = 19, 46.3%), 3) 3-6 months after surgery (n = 11, 26.8%), and 4) 6 months-1 year after surgery (n = 2, 4.9%). In addition, there were significantly larger retear sizes in the Sugaya's classification in the early group compared to the late group (P = .013), while there were significantly more males in the late group compared to the early group (P = .030).

CONCLUSION

The highest retear rate after ARCR was observed from 6 weeks to 3 months after surgery, with equivalent rates within 6 weeks and from 3 months to 6 months after surgery.

Scaffold- and graft-based biological augmentation of rotator cuff repair: an updated systematic review and meta-analysis of preclinical and clinical studies for 2010-2022

BACKGROUND

Despite advancements in the surgical techniques of rotator cuff repair (RCR), there remains a high retear rate. Biological augmentation of repairs with overlaying grafts and scaffolds may enhance healing and strengthen the repair construct. This study aimed to investigate the efficacy and safety of scaffold-based (nonstructural) and overlay graft-based (structural) biological augmentation in RCR (excluding superior capsule reconstruction and bridging techniques) in both preclinical and clinical studies.

METHODS

This systematic review was performed in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, as well as guidelines outlined by The Cochrane Collaboration. A search of the PubMed, Embase, and Cochrane Library databases from 2010 until 2022 was conducted to identify studies reporting the clinical, functional, and/or patient-reported outcomes of ≥1 biological augmentation method in either animal models or humans. The methodologic quality of included primary studies was appraised using the Checklist to Evaluate a Report of a Non-pharmacological Trial (CLEAR-NPT) for randomized controlled trials and using the Methodological Index for Non-randomized Studies (MINORS) for nonrandomized studies.

RESULTS

A total of 62 studies (Level I-IV evidence) were included, comprising 47 studies reporting outcomes in animal models and 15 clinical studies. Of the 47 animal-model studies, 41 (87.2%) demonstrated biomechanical and histologic enhancement with improved RCR load to failure, stiffness, and strength. Of the 15 clinical studies, 10 (66.7%) illustrated improvement in postoperative clinical, functional, and patient-reported outcomes (eg, retear rate, radiographic thickness and footprint, and patient functional scores). No study reported a significant detriment to repair with augmentation, and all studies endorsed low complication rates. A meta-analysis of pooled retear rates demonstrated significantly lower odds of retear after treatment with biological augmentation of RCR compared with treatment with non-augmented RCR (odds ratio, 0.28; P < .00001), with low heterogeneity (I2 = 0.11).

CONCLUSIONS

Graft and scaffold augmentations have shown favorable results in both preclinical and clinical studies. Of the investigated clinical grafts and scaffolds, acellular human dermal allograft and bovine collagen demonstrate the most promising preliminary evidence in the graft and scaffold categories, respectively. With a low risk of bias, meta-analysis revealed that biological augmentation significantly lowered the odds of retear. Although further investigation is warranted, these findings suggest graft and scaffold biological augmentation of RCR to be safe.

Healthcare costs of failed rotator cuff repairs

Background

The goal of this study was to estimate the short-term (∼2 years) healthcare costs of failed primary arthroscopic rotator cuff repair (RCR) in the United States.

Methods

A review of current literature was performed to estimate the number of RCR performed in the United States in the year 2022 and the rate of progression of these patients to lose repair continuity, reach clinical failure, and progress to nonoperative intervention and revision procedures. A review of the current literature was performed to estimate the costs incurred by these failures over the ensuing 2-year postoperative time period.

Results

The direct and indirect healthcare costs of structural and clinical failure of primary RCR performed in 2022 are estimated to reach $438,892,670 in the short-term postoperative period. The majority of the costs come from the estimated $229,390,898 in nonoperative management that these patients undergo after they reach clinical failure.

Conclusion

The short-term healthcare costs of failed arthroscopic RCR performed in the United States in 2022 are predicted to be $438,892,670. Although RCR improves quality of life, pain, function, and is cost-effective, there remains great potential for reducing the economic burden of failed RCR repairs on the US society. Investments into research aimed to improve RCR healing rates are warranted.

Clinical Relevance

Although RCR improves quality of life, pain, function, and is cost-effective, this study provides evidence that there remains great potential for reducing the economic burden of failed RCR repairs on the US society. Investments into research aimed to improve RCR healing rates are warranted.

Non-selective NSAIDs do not increase retear rates post-arthroscopic rotator cuff repair: A meta-analysis

BACKGROUND

Arthroscopic rotator cuff repairs (RCRs) are known to be associated with substantial pain and post-operative pain management is critical in overall patients' outcomes. Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used oral medications and can reduce opioid usage. However, controversies arise due to its postulated effect on postoperative tendon healing. As the evidence of safety and efficacy of NSAIDs remains unclear, this study aims to investigate the effect of NSAIDs on retear rates and clinical outcomes.

METHODS

A systematic search of four databases (PubMed, EMBASE, Scopus, and Cochrane Library) was conducted, identifying studies that compared cohorts with post-RCR NSAIDs use versus control groups without NSAID use. Meta-analysis was conducted for retear rate as well as pain and functional outcomes (Visual Analogue Scale and American Shoulder and Elbow Surgeons Shoulder score). Subgroup analysis was conducted for retear rates to determine the overall treatment effect of including selective COX-2 inhibitors.

RESULTS

Six studies were included in the meta-analysis. The total baseline cohort size was 916, with 443 (48.3%) patients in the NSAID group and 473 (51.6%) patients in the control group. There were no statistically significant differences in the baseline characteristics between the two groups. Meta-analysis between the two groups showed that there were no statistically significant differences in retear rates (p ​= ​0.70), early and late post-operative Visual Analogue Scale score (p ​= ​0.10 and p ​= ​0.10, respectively) and latest American Shoulder and Elbow Surgeons Shoulder score (p ​= ​0.31). However, subgroup analysis of retear rates revealed a statistically significant difference between the subgroup including COX-2 selective inhibitor versus non-selective COX inhibitor (p ​< ​0.01).

CONCLUSION

NSAID use in post-arthroscopic RCR pain relief does not increase retear rates and can provide similar clinical outcomes compared to a non-NSAID regimen.

LEVEL OF EVIDENCE

Meta-analysis, level of evidence, 4.

Combined Growth Factor Hydrogel Enhances Rotator Cuff Enthesis Healing in Rat But Not Sheep Model

We hypothesized that a combined growth factor hydrogel would improve chronic rotator cuff tear healing in a rat and sheep model. Insulin-like growth factor 1, transforming growth factor β1, and parathyroid hormone were combined into a tyraminated poly-vinyl-alcohol (PVA-Tyr) hydrogel and applied directly at the enthesis. In total, 30 Sprague-Dawley rats and 16 Romney ewes underwent unilateral rotator cuff tenotomy and then delayed repairs were performed after 3-4 weeks. The animals were divided into a control group (repair alone) and treatment group. The rotator cuffs were harvested at 12 weeks after surgery for biomechanical and histological analyses of the repair site. In the rat model, the stress at failure and Young's modulus were higher in the treatment group in comparison with the control group (73% improvement, p = 0.010 and 56% improvement, p = 0.028, respectively). Histologically, the repaired entheses in the treatment group demonstrated improved healing with higher semi-quantitative scores (10.1 vs. 6.55 of 15, p = 0.032). In the large animal model, there was no observable treatment effect. This PVA-Tyr bound growth factor system holds promise for improving rotator cuff healing. However, our approach was not scalable from a small to a large animal model. Further tailoring of this growth factor delivery system is still required. Level of Evidence: Basic Science Study; Biomechanics and Histology; Animal Model Impact Statement Previous studies using single-growth factor treatment to improve enthesis healing after rotator cuff repair have reported promising, but inconsistent results. A novel approach is to combine multiple growth factors using controlled-release hydrogels that mimic the normal healing process. In this study, we report that a combined growth factor hydrogel can improve the histological quality and strength of rotator cuff repair in a rat chronic tear model. This novel hydrogel growth factor treatment has the potential to be used in human clinical applications to improve healing after rotator cuff repair.

Determination of the reference range for semi-quantified elasticity of healthy supraspinatus muscles using real-time tissue elastography and its clinical use in patients after rotator cuff repair

BACKGROUND

The quantitative assessment of healthy supraspinatus muscle elasticity may provide clinically useful preliminary information after rotator cuff repairs. We aimed to determine the reference range for supraspinatus muscle semi-quantified elasticity and describe how it can be used clinically after rotator cuff repair.

METHODS

The elasticity of healthy bilateral supraspinatus muscles in 43 participants aged between 24 and 75 years (categorized into two subgroups: <50 and ≥ 50 years) was measured as a strain ratio at 0° and 60° of shoulder abduction using real-time tissue elastography. The reference and modified reference ranges calculated by excluding outliers for elasticity were determined using normal distribution methods for logarithmically transformed data. The modified reference range was applied to eight cases of rotator cuff repair.

FINDINGS

Strain ratios under and over 50 years of age were 1.63 vs. 2.21 at 0° of shoulder abduction (P = 0.028) and 0.92 vs. 1.29 at 60° of shoulder abduction (P = 0.002), respectively. Modified reference ranges for under and over 50 years of age were 0.72-4.17 and 0.98-4.50 at 0° of shoulder abduction and 0.38-1.95 and 0.56-2.76 at 60° of shoulder abduction, respectively. Among eight cases, two showed strain ratios above the reference range at 1 month postoperatively, and rehabilitation protocols were adjusted.

INTERPRETATION

A strain ratio above the reference range, especially above the upper limit at 0° of shoulder abduction, may indicate increased passive stiffness of the musculotendinous unit. Clinically, the reference range has the potential to be used as a baseline after rotator cuff repairs.

A Knitted PET Patch Enhances the Maturation of Regenerated Tendons in Bridging Reconstruction of Massive Rotator Cuff Tears in a Rabbit Model

BACKGROUND

Although nondegradable synthetic grafts for bridging reconstruction of massive rotator cuff tears (MRCTs) have shown satisfactory clinical outcomes, their function and details on graft-tendon healing and enthesis regeneration have not been fully studied.

HYPOTHESIS

The knitted polyethylene terephthalate (PET) patch as a nondegradable synthetic graft could provide sustained mechanical support, facilitating enthesis and tendon regeneration in the treatment of MRCTs.

STUDY DESIGN

Controlled laboratory study.

METHODS

A knitted PET patch was fabricated for bridging reconstruction (PET group) in a New Zealand White rabbit model of MRCTs (negative control group), and an autologous Achilles tendon was used as a control (autograft group). The animals were sacrificed, and tissue samples were harvested for gross observation as well as histological and biomechanical analyses at 4, 8, and 12 weeks postoperatively.

RESULTS

Histological analysis showed no significant difference in the graft-bone interface score between the PET and autograft groups at 4, 8, and 12 weeks postoperatively. Interestingly, in the PET group, Sharpey-like fibers were observed at 8 weeks, while fibrocartilage formation and the ingrowth of chondrocytes were recognized at 12 weeks. Meanwhile, the tendon maturing score was significantly higher in the PET group than in the autograft group (19.7 ± 1.5 vs 15.3 ± 1.2, respectively; P = .008) at 12 weeks, with parallel-oriented collagen fibers around the knitted PET patch. Moreover, the ultimate failure load of the PET group was similar to that of a healthy rabbit tendon at 8 weeks (125.6 ± 13.6 vs 130.8 ± 28.6 N, respectively; P > .05) and no different from that of the autograft group at 4, 8, and 12 weeks.

CONCLUSION

The knitted PET patch could not only immediately reconstruct the mechanical support for the torn tendon postoperatively in the rabbit model of MRCTs but also enhanced maturation of the regenerated tendon by fibrocartilage formation and improved the organization of collagen fibers. Herein, the knitted PET patch could be a promising candidate graft adopted in bridging reconstruction of MRCTs.

CLINICAL RELEVANCE

A nondegradable knitted PET patch can safely bridge MRCTs with satisfactory mechanical strength and the promotion of tissue regeneration.

Local Intraoperative Marrow-Derived Augmentation for Primary Rotator Cuff Repair: An Updated Systematic Review and Meta-analysis of Studies From 2010 to 2022

Background

Recurrent tears of the rotator cuff pose a substantial problem despite advances in repair technique. Biologic augmentation via marrow stimulation or vented anchors may strengthen the suture-tendon junction and improve healing rates of native tissue, thereby enhancing outcomes of primary surgical repair.

Purpose

To provide a focused systematic review and meta-analysis of local, intraoperative marrow-derived augmentation techniques in clinical primary rotator cuff repair.

Study Design

Systematic review; Level of evidence, 4.

Methods

A systematic review of PubMed, Embase, and Cochrane was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A total of 2131 studies from 2010 to 2022, focused on either marrow stimulation or vented anchors, were isolated and classified as either preclinical or clinical. Meta-analysis was performed for comparative marrow stimulation and vented anchor studies. Heterogeneity was tested through calculation of I ².

Results

A total of 13 clinical studies were included in the review. All 9 comparative studies included in the meta-analysis demonstrated high methodologic quality or a low risk of bias. The pooled retear rate across all 9 clinical studies for patients undergoing marrow stimulation was 11%. For the 5 studies in the meta-analysis, the pooled retear rates were 15% for marrow stimulation and 30% for controls. Meta-analysis demonstrated a significant difference in the overall retear rate that favored marrow stimulation (odds ratio [OR], 0.41; 95% CI, 0.25-0.66; P = .0003; I ² = 0%). Similarly, meta-analysis of the Constant score at final follow-up demonstrated a statistically significant difference between the 2 groups that favored a higher Constant score in the marrow stimulation group (mean difference, 2.84; 95% CI, 1.02-4.66; P = .002; I ² = 29%). Vented anchors demonstrated improved ossification and bone density at the anchor site, but no difference in outcomes or retear. Pooled retear rates were 22.5% for vented anchors and 27.8% for controls.

Conclusion

Current evidence demonstrates that marrow-stimulation techniques may have a positive impact on healing and retear rate, while vented anchors have a muted impact relative to nonvented anchors. Although available evidence is limited and more research is needed, findings to date suggest that marrow stimulation techniques may be an inexpensive, straightforward technique to consider in qualifying patients to prevent rotator cuff retears.

Evidence for Utilization of Injectable Biologic Augmentation in Primary Rotator Cuff Repair: A Systematic Review of Data From 2010 to 2022

Background

Biologic healing after rotator cuff repair remains a significant challenge. Injectable biologic augmentation may improve tissue quality at the suture-tendon interface.

Purpose

To investigate the effect of injectable biologic supplementation in rotator cuff repair and to assess the quality and adherence to evolving reporting standards.

Study Design

Systematic review; Level of evidence, 3.

Methods

A systematic review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were 40 studies: 29 preclinical (in vivo animal models) and 11 clinical. Each clinical study was assessed for quality, risk of bias, and adherence to relevant MIBO (Minimum Information for Studies Evaluating Biologics in Orthopaedics) guidelines. The outcomes of interest were reported load to failure, load to gap, gap size, and stiffness in the preclinical studies, and healing rate and any patient-reported outcome measures in the clinical studies.

Results

Injectables reported included growth factors (eg, transforming growth factor-beta 3, erythropoietin), bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stem cells (ADSCs), and other agents such as platelet-rich plasma (PRP) and hyaluronic acid. The most common findings for preclinical injectables were increased load to failure (16/29 studies; 55.2%) and improved collagen histological quality (11/29 studies; 37.9%). All 11 clinical studies (10 PRP, 1 ADSC) indicated no adverse events, with similar or improved patient-reported outcomes compared with repairs in the control groups. In 1 study utilizing an innovative delivery technique, a concentrated PRP globule with fibrin matrix was shuttled over a suture to maintain concentrated PRP at the repair site and demonstrated a significant decrease in retears (P = .03) at a 31-month follow-up. A matched-cohort study investigating augmentation with ADSCs demonstrated a significantly lower retear rate in the ADSC-augmented group than the control group at a 28-month follow-up (P < .001). On average, the clinical studies adhered to 66% of relevant MIBO reporting guidelines and had a low risk of bias.

Conclusion

Approximately 83% of preclinical studies found a positive biomechanical or histological effect, with no studies showing an overall negative effect. Clinically, utilization of innovative delivery techniques may reduce the risk of arthroscopic washout of PRP and improve retear rates. ADSCs were shown to reduce retear rates at a 28-month follow-up.

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.

Comparison of Locking-Loop Suture Bridge Repair and Single-Row Suture Anchor Repair in Small to Medium Rotator Cuff Tears: A Prospective Cohort Study With Clinical and Ultrasound Evaluations

Background

Single-row (SR) and double-row repair techniques have been described to treat rotator cuff tears. We present a novel surgical strategy of arthroscopic-assisted mini-open repair in which a locking-loop suture bridge (LLSB) is used.

Purpose

To compare the functional outcomes and repair integrity of LLSB technique to the SR technique for arthroscopic-assisted mini-open repair of small to medium rotator cuff tears.

Study Design

Cohort study; Level of evidence, 3.

Methods

Included were 39 patients who underwent LLSB repair (LLSB group) and 44 patients who underwent SR suture anchor repair (SR group) from 2015 to 2018. We evaluated all patients preoperatively and at 3, 6, 12, and 24 months postoperatively using the visual analog scale (VAS) for pain, Oxford Shoulder Score (OSS), and American Shoulder and Elbow Surgeons (ASES) score. Also, shoulder sonography was performed at 12 months postoperatively to evaluate repair integrity using the Sugaya classification system. The independent-sample t test was used to analyze functional outcomes (VAS, OSS, and ASES scores), and the Fisher exact test was used to analyze postoperative sonography results.

Results

Patients in both the LLSB and SR groups saw a significant improvement on all 3 outcome measures from preoperatively to 24 months postoperatively (P < .001 for all). However, when comparing scores between groups, only the scores at 3 months postoperatively differed significantly (VAS: P = .002; OSS: P < .001; ASES: P = .005). Shoulder sonography at 12 months postoperatively revealed no significant difference in repair integrity between the LLSB and SR groups (retear rate: 10.26% and 6.82%, respectively; P = .892).

Conclusion

Better outcome scores were seen at 3-month follow-up in the LLSB group, with no difference in retear rates compared with the SR group at 12 months postoperatively. The LLSB technique was found to be a reliable technique for rotator cuff repair of small- to medium-sized tears.

Arthroscopic revision cuff repair: do tendons have a second chance to heal?

BACKGROUND

Few studies have investigated postoperative tendon integrity after reoperation for failed rotator cuff repair. The purpose of this study was to evaluate the anatomic and clinical outcomes of arthroscopic revision rotator cuff repair (AR-RCR) and identify the risk factors related to re-retear.

METHODS

Sixty-nine consecutive patients (mean age, 55 years) with primary failed open (38%) or arthroscopic (62%) cuff repairs underwent AR-RCR and were reviewed regarding clinical examination findings and imaging studies. Patients with massive cuff tears and upward humeral migration (acromiohumeral distance < 6 mm) or glenohumeral osteoarthritis were excluded. Revision repair was performed by a single, experienced shoulder surgeon. Complete footprint coverage was achieved in all cases using a single-row (70%), double-row (19%), or side-to-side (11%) technique. The primary outcome measure was tendon healing assessed with magnetic resonance imaging (57 cases) or computed tomography arthrogram (12 cases) performed at minimum 1-year follow-up. Secondary outcome measures included functional outcome scores, subjective results, and complications. The mean follow-up period was 43 months (range, 12-136 months).

RESULTS

The cuff tendons did not heal to the tuberosity in 36% of the shoulders (25 of 69) following revision cuff surgery. Absence of tendon healing was associated with poorer shoulder function (average Constant score, 69 ± 20 vs. 54 ± 18; P = .003) and a decreased Subjective Shoulder Value (72% vs. 54%, P = .002). Factors that were negatively associated with tendon healing were age ≥ 55 years (odds ratio [OR], 4.5 [95% confidence interval, 1.6-12.5]; P = .02), tendon retraction of stage 2 or higher (OR, 4.4 [95% confidence interval, 1.4-14.3]; P = .01), and fatty infiltration index > 2 (OR, 10.2; P < .0001). No differences in retear rates were found between single-row and double-row cases. In 36 shoulders, tissue samples were harvested and submitted for bacteriologic culture analysis; 13 (36%) showed positive findings for infection (Cutibacterium acnes in 12 of 13) and associated antibiotic treatment was given. Overall, 25% of patients had unsatisfactory clinical results and 22% were disappointed or dissatisfied. At last follow-up, 4 patients (5.7%) underwent reoperations, with a second AR-RCR in 1 and conversion to reverse shoulder arthroplasty in 3.

CONCLUSION

Despite careful patient selection and intraoperative complete footprint coverage, in this study the tendons did not heal to bone in 36% of cases after revision cuff surgery. The absence of tendon healing is associated with poorer clinical and subjective results. Patients aged ≥ 55 years and patients with larger tears (stage 2 or higher) and/or muscle fatty infiltration (fatty infiltration index > 2) have significantly lower rates of healing. Surgeons should be aware that structurally failed cuff repair may also be associated with low-grade infection.

Effect of Quality of Repair on Clinical and Structural Outcomes of Rotator Cuff Repair

BACKGROUND

Anatomic repair of a torn rotator cuff tendon on the greater tuberosity (GT) is an important surgical goal in rotator cuff repair. However, few studies have investigated whether the efforts made to maximize coverage of the GT are associated with the clinical and structural outcomes after rotator cuff repair surgery.

PURPOSE

To investigate whether the quality of repair at the time of surgery is associated with clinical and structural outcomes after surgery and to identify factors influencing the quality of repair.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were retrospectively collected from 141 patients who underwent arthroscopic rotator cuff repair between 2008 and 2016. All repairs were classified according to the amount of postoperative GT coverage: A, complete coverage of the GT (n = 96); B, incomplete coverage, comprising more than half of GT (n = 27); C, incomplete coverage, comprising less than half of the GT (n = 16); and D, exposure of the glenohumeral joint (n = 2). All patients underwent magnetic resonance imaging 1 year after surgery. Clinical outcomes and structural integrity based on Sugaya classification were assessed 2 years and 1 year after surgery, respectively. Preoperative factors associated with the postoperative GT coverage (measured at the close of surgery) were identified using a multivariable proportional odds cumulative logit model.

RESULTS

The forward flexion strength in group A (10.3 ± 4.6 lb) was significantly greater than that in group C (6.5 ± 3.7 lb) (P = .003) 2 years after surgery. The postoperative Constant score in group A (76.6 ± 11.5) was greater than that in group C (66.7 ± 15.6) (P = .018). The number of cases that showed retearing of the repaired tendon was as follows: group A (5/96; 5.2%), group B (7/27; 25.9%), and group C (10/16; 62.5%). There was no significant difference in the changes of pain visual analog scale scores among groups 2 years after surgery (all P > .05). Also, there was no significant difference in the changes of range of motion in all directions among groups 2 years after surgery (all P > .05). Patients with preoperative GT coverage B included in the postoperative GT coverage groups through surgery were as follows: group A (23/45; 51.1%), group B (17/45; 37.8%), and group C (5/45; 11.1%). Preoperative GT coverage was the only independent factor that was associated with GT coverage in multivariable analysis.

CONCLUSION

Quality of repair, measured as the extent of postoperative GT coverage at the time of surgery, was associated with clinical and structural outcomes after rotator cuff repair surgery.

Can the Single Assessment Numeric Evaluation be used as a stand-alone subjective outcome instrument in patients undergoing rotator cuff repair?

BACKGROUND/HYPOTHESIS

There is no consensus to which patient-determined shoulder outcome scores should be considered when analyzing patient outcomes. Use of multiple patient-determined outcomes may be redundant and cause increased responder burden. The Single Assessment Numeric (SANE) has not been widely accepted as a stand-alone shoulder-specific outcome measure. The hypothesis was that SANE will correlate with and be comparable in responsiveness to other subjective outcome measures that have been used in a stand-alone fashion in patients undergoing rotator cuff repair (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form [ASES], Western Ontario Rotator Cuff Index [WORC], and the Simple Shoulder Test [SST]). In addition, the SANE will be more relevant to each patient compared to the ASES, further supporting its use as a stand-alone shoulder-specific outcomes measure.

METHODS

A retrospective review of a database of patients undergoing rotator cuff repair was reviewed where the SANE was recorded with the ASES, WORC, and/or SST. Correlations were determined using the Pearson coefficient. Subgroup analysis was performed to determine if correlations differed in (1) preoperative and (2) postoperative outcome determinations. Responsiveness was determined by calculating the standardized response mean (SRM) and the effect size (ES) of all scores. Relevance and precision of the SANE and ASES were examined using 150 consecutive patients to determine the number of questions in each score that were not answered.

RESULTS

Correlation was excellent for the SANE and the ASES (n = 1838, r = 0.81, P < .0001), the WORC (n = 1793, r = 0.82, P < .0001), and the SST (n = 1836, r = 0.76, P < .0001). Correlation of preoperative scores was moderate and postoperative scores were excellent when comparing the SANE with all 3 scores. All scores were highly responsive, with the SRM of the SANE = 2.1, ASES = 2.2, WORC = 2.4, and the SST = 1.8. The ES of the SANE = 2.4, ASES = 2.7, WORC = 3.0, and the SST = 2.1. One hundred percent of the SANE scores were answered completely compared with 57% (P < .0001) of the ASES, with significant variability found in the answers to the "work" and "score" questions.

CONCLUSION

In patients undergoing rotator cuff repair, the SANE highly correlated and has equivalent responsiveness with the WORC, ASES, and SST, which have been used as stand-alone shoulder-specific outcomes measures. The SANE may provide the same information as the WORC, ASES, and SST regarding outcome with significant reduction in responder burden. This study supports that the SANE can be used as a subjective, stand-alone instrument for patients undergoing rotator cuff repair.

Patient Acceptable Symptom State, Minimal Clinically Important Difference, and Substantial Clinical Benefit After Arthroscopic Superior Capsular Reconstruction

BACKGROUND

Patient Acceptable Symptom State (PASS), minimal clinically important difference (MCID), and substantial clinical benefit (SCB) have rarely been assessed after arthroscopic superior capsular reconstruction (ASCR) with fascia lata autograft.

PURPOSE

(1) To investigate PASS, MCID, and SCB values for pain visual analog scale (pVAS), American Shoulder and Elbow Surgeons (ASES) score, Constant score, and Single Assessment Numeric Evaluation (SANE) after ASCR with fascia lata autograft, (2) to investigate factors for achieving PASS, MCID, and SCB.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

We retrospectively collected data from patients who underwent ASCR between June 2013 and October 2020. A total of 88 patients were included, and anchor questions for deriving PASS, MCID, and SCB values were applied at a minimum 1-year follow-up postoperatively. PASS, MCID, and SCB were derived using sensitivity- and specificity-based approaches. Univariable and multivariable logistic regression analyses were performed to determine factors for achieving PASS, MCID, and SCB.

RESULTS

Based on receiver operating characteristic curves, all 4 scores had acceptable area under the curve values (>0.7) for PASS, MCID, and SCB values. The PASS, MCID, and SCB values were 1.5, 2.5, and 4.5 for pVAS; 81.0, 19.0, and 27.5 for the ASES score; 60.5, -0.5, and 5.5 for the Constant score; and 75.0, 27.5, and 32.5 for SANE, respectively. Poor preoperative scores were related to significantly higher odds ratios (ORs) for achieving MCID and SCB. Wide acromiohumeral distance and dominant side were related to higher ORs for achieving PASS for the ASES score, and subscapularis tear was related to lower ORs for achieving PASS for pVAS and SCB for the Constant score.

CONCLUSION

Reliable PASS, MCID, and SCB values were achieved for at least 1 year after ASCR surgery. Poor preoperative score, wide acromiohumeral distance, and dominant side all demonstrated higher ORs for at least one value, but a subscapularis tear demonstrated lower ORs for achieving PASS for pVAS and SCB for the Constant score.

Does Complete Footprint Coverage Affect Outcomes After Conventional Arthroscopic Repair of Large-Sized Rotator Cuff Tears?

Background:

In large-sized rotator cuff tears, tendon repair with incomplete footprint coverage is performed frequently as a way of tension-free or low-tension repair.

Purpose:

To compare clinical outcomes after arthroscopic repair of large-sized rotator cuff tears between patients with complete versus incomplete footprint coverage.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Among 297 patients who underwent arthroscopic surgery for a large-sized rotator cuff tear, we selected 58 patients (<50% coverage; mean age, 63.34 ± 6.8 years; 34 men and 24 women) with incomplete footprint coverage. Using propensity score matching, another 58 patients with complete footprint coverage (mean age, 63.4 ± 8.03 years; 34 men and 24 women) were selected after 1:1 matching for age, sex, and tear size—the main demographic and prognostic factors of outcomes after rotator cuff repair. Clinical outcomes were compared on magnetic resonance imaging or ultrasonography at minimum of 6 months postoperatively, and functional outcomes were compared using range of motion and pain visual analog scale; American Shoulder and Elbow Surgeons; Constant; University of California, Los Angeles; and Simple Shoulder Test scores at a minimum of 2 years postoperatively.

Results:

A total of 18 patients in the incomplete footprint coverage group (31.0%) and 20 patients in the complete footprint coverage group (34.5%) showed healing failure, with no significant difference between groups (P = .843). In addition, there were no differences in functional outcomes between groups (P > .05 for all).

Conclusion:

Whether the rotator cuff footprint was completely covered did not affect clinical outcomes in conventional arthroscopic repair of large-sized rotator cuff tears.

Satisfactory functional and structural outcomes of anterior cable reconstruction using the proximal biceps tendon for large retracted rotator cuff tears

PURPOSE

Large retracted anterior L-shaped tear characterized by a retracted supraspinatus tendon to the glenoid level combined with a relatively preserved infraspinatus tendon is one of the challenging tear patterns in achieving complete repair to the anatomic footprint. The purpose of this study was to evaluate clinical outcomes and tendon integrity of rotator cuff repair combined with anterior cable reconstruction using the proximal biceps tendon in patients with large retracted anterior L-shaped rotator cuff tear.

METHODS

This study prospectively enrolled patients who underwent arthroscopic anterior cable reconstruction using the proximal biceps tendon for large retracted anterior L-shaped rotator cuff tears between 2018 and 2020 with a minimum 2-year follow-up. The anterior portion of the rotator cable was reconstructed using tenotomized proximal biceps tendon fixed with two suture anchors at the footprint. The retracted supraspinatus tendon was repaired on the biceps tendon without undue tension. The proximal portion of the infraspinatus tendon was repaired with the biceps tendon-supraspinatus tendon complex. Clinical outcomes was assessed during the follow-up period. Tendon integrity and retear size were evaluated by postoperative MRI.

RESULTS

A total of 32 consecutive patients were included. The ASES score was significantly improved from 66.6 ± 16.6 preoperatively to 94.1 ± 6.1 postoperatively (P < 0.001), and the VAS for pain was significantly relieved from 2.8 ± 1.9 preoperatively to 0.5 ± 0.4 postoperatively (P < 0.001). All patients were satisfied postoperatively regardless of tendon integrity (P = 0.015). Postoperative ROM was increased continuously during the follow-up period (P < 0.001). The Popeye sign was found in 4 patients (12.5%). Six patients (18.7%) had rotator cuff retears. However, the ASES score of patients with retear was significantly improved from 72.8 ± 13.3 preoperatively to 91.1 ± 6.7 postoperatively (P < 0.001). Relative changes in the retear size compared with the primary tear size were -56.8 ± 14.4% for the anteroposterior diameter and - 70.6 ± 6.1% for the mediolateral diameter.

CONCLUSIONS

Rotator cuff repair combined with anterior cable reconstruction using the proximal biceps tendon provided satisfactory clinical and radiological outcomes for large retracted anterior L-shaped tears. Anterior cable reconstruction using the proximal biceps tendon is a sound surgical option for the patients with large retracted anterior rotator cuff tear.

LEVEL OF EVIDENCE

IV.

Quantitative Magnetic Resonance Imaging measurement of muscle atrophy and fatty degeneration after arthroscopic rotator cuff repair

BACKGROUND

It is unclear whether muscle atrophy (MA) and fatty degeneration (FD) have improved after arthroscopic rotator cuff repair (ARCR). Therefore, the objective of this study was to perform quantitative magnetic resonance imaging (MRI) measurement to evaluate MA and FD before and after surgery. Correlations of clinical outcome with changes in MA and FD were also analyzed.

MATERIALS AND METHODS

From March 2013 to March 2017, 40 patients who had no re-tear up to 1 year after ARCR were enrolled. MA and FD of supraspinatus muscle before surgery, at 3 days after surgery, and at 1 year after surgery were measured quantitatively in conventional Y-view and supraspinatus origin-view (SOV). Measurement items were muscle area (mm²), occupation ratio (%), fatty infiltration (FI, %), and fatty degenerative area (mm²). Postoperative clinical outcomes were measured at 1 year after ARCR. Correlation between measure values and outcome scores were analyzed.

RESULTS

Inter-measurement reliability was high (ICC = 0.933, Cronbach-α = 0.963). There was no significant change in MA in conventional Y-view at 1 year after surgery (Occupation ratio, p = 0.2770; MA, p = 0.3049) or in SOV (MA, p = 0.5953). FI and fat area measured with the conventional method on Y-view and showed significant differences (p = 0.0001). However, FI and fat area measured with the modified method on Y-view and SOV showed no significant difference (all p > 0.05). Postoperative clinical outcomes showed significant improvement compared to preoperative ones (p = 0.0001). However, there was no significant correlation between FD and FA (p = 0.653).

CONCLUSION

Quantitative MRI measurement was shown to be a reliable and valid method. MA and FD do not improve after ARCR considering postoperative anatomical changes of supraspinatus at 1-year follow-up. FD of the supraspinatus in conventional Y-view, but not in SOV, showed a significant change at 1 year postoperatively. MA showed no significant improvement. There was no correlation between improvement in clinical scores and changes in FD and MA.

Clinical outcomes and structural integrity rate of arthroscopic augmented rotator cuff repairs using extracellular porcine matrix patch

BACKGROUND

Structural failure rate in rotator cuff repairs is still high. The purpose of the study is to assess the structural integrity of a series of augmented rotator cuff repairs with porcine matrix patch and report the functional outcomes.

METHODS

Between 2014 and 2017, 44 consecutive patients underwent arthroscopic double-row repair of medium to massive rotator cuff tears with extracellular porcine dermal matrix augmentation. At one-year follow-up, magnetic resonance imaging scan was performed to assess the integrity of the repair. Oxford Shoulder Score (OSS), Constant Score (CS) and Visual Analogue Scale pain score, together with range of motion were used to assess patients.

RESULTS

Patients mean age was 68 (53-82); mean follow-up was 17.2 (12-24) months. On magnetic resonance imaging scans, seven rotator cuff repair failures (15.9%) were observed: tear size was an independent predictor of re-rupture at one-year follow-up. Clinical scores showed a statistically significant improvement at three months and until final follow-up (p< 0.001). No complications occurred.

CONCLUSION

Observed structural failure rate of 15.9% is lower than those reported in the literature for standard rotator cuff repair of medium to massive tears in similar cohorts to ours. Extracellular matrix augmentation for rotator cuff repair was shown to be a safe and reliable support to the repairs and patients recovered good shoulder function.Level of Evidence: Level IV.

Changes From Baseline in Patient- Reported Outcomes at 1 Year Versus 2 Years After Rotator Cuff Repair: A Systematic Review and Meta-analysis

BACKGROUND

Most orthopaedic journals currently require reporting outcomes of surgical interventions for at least 2 postoperative years, but there have been no rigorous studies on this matter. Various patient-reported outcome (PRO) measures (PROMs) have been used to assess the status of the shoulder after rotator cuff repair (RCR).

HYPOTHESIS

We hypothesized that the mean shoulder-specific PROMs at 1 year improve substantially over baseline but that there is no clinically meaningful difference between the mean 1- and 2-year PROMs after RCR.

STUDY DESIGN

Meta-analysis; Level of evidence, 2.

METHODS

We conducted a systematic review of published randomized controlled trials (RCTs) and prospective cohort studies (level of evidence 1 and 2) reporting the shoulder-specific American Shoulder and Elbow Surgeons (ASES), the Constant, or the Western Ontario Rotator Cuff (WORC) Index scores at baseline, 1 year, and 2 years after RCR. The methodologic quality of studies was assessed. Also, the random effects meta-analyses of changes in PROMs for each of the first and second postoperative years were conducted.

RESULTS

Fifteen studies (n = 11 RCTs; n = 4 cohort studies) with a total of 1371 patients were included. Studies were highly heterogeneous, but no visual evidence of major publication bias was observed. The weighted means of the baseline PROMs were 46.2 points for the ASES score, 46.4 points for the Constant score, and 38.8 points for the WORC Index. The first-year summary increments were 41.1 (95% CI, 36.0-46.2) points for the ASES score, 34.2 (95% CI, 28.8-39.6) points for the Constant score, and 42.9 (95% CI, 37.3-48.4) points for the WORC Index. In contrast, the second-year summary increments were 2.3 (95% CI, 1-3.6) points for the ASES score, 3.2 (95% CI, 1.9-4.4) points for the Constant score, and 2 (95% CI, -0.1 to 4) points for the WORC Index.

CONCLUSION

All PROMs improved considerably from baseline to 1 year, but only very small gains that were below the minimal clinically important differences were observed between 1 year and 2 years after RCR. This study did not find any evidence for requiring a minimum of 2 years of follow-up for publication of PROs after RCR. Our results suggest that focusing on 1-year PROMs after RCR would foster more timely reporting, better control of selection bias, and better allocation of research resources.

Arthroscopic Repair of Isolated Subscapularis Tears Show Clinical and Structural Outcome Better for Small Tears Than Larger Tears

Purpose

To retrospectively investigate the mid-term outcomes after arthroscopic repair of isolated subscapularis tears with a relatively large number of patients and to compare them by tear size.

Methods

Medical records were reviewed for patients who underwent arthroscopic rotator cuff repair between 2010 and 2017 at our institute. The inclusion criterion was isolated subscapularis tears that underwent arthroscopic rotator cuff repair. The exclusion criteria were (1) previous rotator cuff surgery, (2) lack of imaging studies or clinical evaluation data, (3) neuromuscular diseases, and (4) <2-year follow-up. Range of motion, American Shoulder and Elbow Society score, and bear-hug or belly-press test were assessed pre- and postoperatively. Repair integrity was evaluated with magnetic resonance imaging at postoperative1 year. The clinical and imaging study outcomes were compared between smaller (Lafosse types 1-3) and larger (types 4 and 5) tears.

Results

The subjects included 38 males and 8 females with a mean age of 59 years (range, 25-77 years). The mean follow-up was 36 months (range, 24-96 months). There were 13 type 1, 10 type 2, 12 type 3, 6 type 4, and 5 type 5 shoulders. Postoperative American Shoulder and Elbow Society scores were significantly better in smaller tears than larger tears: 93 ± 8 and 75 ± 14, respectively (P = .003). Smaller tears showed better postoperative internal rotation than larger tears (P = .004). Significant decrease of positive bear-hug or belly-press test was observed in smaller tears (preoperative, 25; postoperative, 11; P < .001), but there was no significant improvement in larger tears (preoperative, 11; postoperative, 9). The retear rate was significantly greater in larger tears (64%) than smaller tears (6%, P < .001).

Conclusions

The clinical and structural outcomes after arthroscopic repair of isolated subscapularis tears were better in smaller tears than larger tears with a mid-term follow-up. Larger tears showed high retear rates with poorer improvement in active range of internal rotation and subscapularis strength.

Level of Evidence

Level III, retrospective, comparative study.

Owen, Sugaya, and Hayashida Classifications Give Poor Intra- and Inter-Rater Agreement on a Magnetic Resonance Imaging Evaluation of Subscapularis Tendon Retears

PURPOSE

To investigate the intra- and inter-rater agreements for magnetic resonance imaging (MRI) evaluations of subscapularis tendon integrity at 6 months after arthroscopic rotator cuff repairs.

METHODS

Patients who had isolated or combined subscapularis tears and had undergone arthroscopic rotator cuff repairs were retrospectively included. The exclusion criteria included revision of arthroscopic surgery, minor subscapularis tears without repair, and inadequate postoperative images. MRI scans 6 months after surgery were used for the purpose of accessing the integrity of the subscapularis tendons. Three orthopaedic surgeons blindly evaluated the images twice at 2-week intervals. Three currently available classifications were used: the Owen classification, the Sugaya classification, and the Hayashida classification. Dichotomization and trichotomization methods were used for the Sugaya classification and Hayashida classifications. The aforementioned classification scores were combined for the agreement evaluation. Intra- and inter-rater agreement was assessed by calculating the Fleiss' kappa coefficients.

RESULTS

A total of 35 patients were included. Both the Owen and Hayashida classifications had poor inter-rater agreements (κ = 0.10 and 0.04, respectively) and poor-to-weak intra-rater agreements (κ = 0.27-0.44 and 0.16-0.45, respectively). The Sugaya classification had poor inter-rater agreement (κ = 0.10) and poor intra-rater agreements (κ = 0.16-0.32). Dichotomization and trichotomization of Sugaya and Hayashida classifications did not lead to superior agreements. The classification combination resulted in poor inter- and intra-rater agreements (κ = 0.01-0.12 and 0.08-0.39, respectively).

CONCLUSIONS

The Owen classification, Sugaya classification, and Hayashida classification had poor intra- and inter-rater agreement in terms of evaluating subscapularis tendon re-tears on 6 months' postoperative MRI. The dichotomized and trichotomized classifications as well as the combined classifications from currently available classifications did not lead to superior agreements.

LEVEL OF EVIDENCE

Level IV, diagnostic: case series.

Quantifying shoulder activity after rotator cuff repair: Technique and preliminary results

Repair tissue healing after rotator cuff repair remains a significant clinical problem, and excessive shoulder activity after surgical repair is believed to contribute to re-tears. In contrast, small animal studies have demonstrated that complete removal of activity impairs tendon healing and have advocated for an "appropriate" level of activity, but in humans the appropriate amount of shoulder activity to enhance healing is not known. As an initial step toward understanding the relationship between postoperative shoulder activity and repair tissue healing, the objectives of this study were to assess the precision, accuracy, and feasibility of a wrist-worn triaxial accelerometer for measuring shoulder activity. Following assessments of precision (±0.002 g) and accuracy (±0.006 g), feasibility was assessed by measuring 1 week of shoulder activity in 14 rotator cuff repair patients and 8 control subjects. Shoulder activity was reported in terms of volume (mean acceleration, activity count, mean activity index, active time) and intensity (intensity gradient). Patients had significantly less volume (p ≤ .03) and intensity (p = .01) than controls. Time post-surgery was significantly associated with the volume (p ≤ .05 for mean acceleration, activity count, and mean activity index) and intensity (p = .03) of shoulder activity, but not active time (p = .08). These findings indicate this approach has the accuracy and precision necessary to continuously monitor shoulder activity with a wrist-worn sensor. The preliminary data demonstrate the ability to discriminate between healthy control subjects and patients recovering from rotator cuff repair and provide support for using a wearable sensor to monitor changes over time in shoulder activity.

Utility of Preoperative Shear-Wave Elastography of the Supraspinatus Muscle for Predicting Successful Rotator Cuff Repair: A Prospective Observational Study With MRI Correlation

BACKGROUND. After rotator cuff tear, properties of the torn muscle predict failed surgical repair. OBJECTIVE. The purpose of our study was to explore the utility of preoperative shear-wave elastography (SWE) measurements of the supraspinatus muscle to predict successful rotator cuff repair, including comparison with MRI-based measures. METHODS. This prospective study included 74 patients (37 men, 37 women; mean age, 63.9 ± 10.0 [SD] years) who underwent rotator cuff repair between May 2019 and January 2021. Patients underwent preoperative clinical shoulder MRI and investigational shoulder ultrasound including SWE using shear modulus. The mean elasticity values of the supraspinatus and trapezius muscles were measured, and the elasticity ratio (i.e., ratio of mean elasticity of supraspinatus muscle to mean elasticity of trapezius muscle) was calculated. The muscular fatty infiltration score (1-3 scale) was recorded on gray-scale ultrasound. On MRI, muscular fatty infiltration was assessed by Goutallier grade (0-4 scale), and muscular atrophy was assessed by the occupation ratio (ratio of cross-sectional areas of supraspinatus muscle and supraspinatus fossa) and by the muscle atrophy grade (0-3 scale). After rotator cuff repair, the surgeon classified procedures as achieving sufficient (n = 60) or insufficient (n = 14) repair. RESULTS. Patients with insufficient repair, versus those with sufficient repair, more commonly exhibited a large (3-5 cm) tear (100.0% vs 50.0%). Patients with insufficient, versus sufficient, repair exhibited higher mean Goutallier grade (3.8 ± 0.4 vs 1.9 ± 1.1), mean muscle atrophy grade (2.0 ± 0.8 vs 0.5 ± 0.7), mean supraspinatus elasticity (44.15 ± 8.06 vs 30.84 ± 7.89 kPa), mean elasticity ratio (3.66 ± 0.66 vs 1.83 ± 0.58), and mean gray-scale fatty infiltration grade (2.86 ± 0.36 vs 1.63 ± 0.66) and showed lower mean occupation ratio (0.3 ± 0.1 vs 0.6 ± 0.1) (all, p < .001). AUC for predicting insufficient repair was 0.945 for Goutallier grade, 0.961 for occupation ratio, 0.900 for muscle atrophy grade, 0.874 for mean elasticity, 0.971 for elasticity ratio, and 0.912 for gray-scale fatty infiltration grade. Elasticity ratio (cutoff ≥ 2.51) achieved sensitivity of 100.0% and specificity of 90.0% for insufficient repair. At multivariable analysis including tear size, the three MRI measures, elasticity ratio, and gray-scale fatty infiltration grade, the only independent predictors of insufficient repair were muscle atrophy grade of 2-3 (odds ratio [OR] = 9.3) and elasticity ratio (OR = 15.7). CONCLUSION. SWE-derived elasticity is higher in patients with insufficient rotator cuff repair; the elasticity ratio predicts insufficient repair independent of tear size and muscle characteristics. CLINICAL IMPACT. Preoperative SWE may serve as a prognostic marker in patients with rotator cuff tear.

In Vivo Static Retraction and Dynamic Elongation of Rotator Cuff Repair Tissue After Surgical Repair: A Preliminary Analysis at 3 Months

Background:

Rotator cuff repair is a common orthopaedic procedure that provides pain relief for many patients, but unfortunately, an estimated 20% to 70% of repair procedures will fail. Previous research has shown that elongation (ie, retraction) of a repaired tendon is common even in patients with a repair construct that appears intact on magnetic resonance imaging. However, it is unknown how this repair tissue functions under dynamic conditions.

Purpose:

To quantify static retraction and maximum dynamic elongation of repair tissue after rotator cuff repair.

Study Design:

Case series; Level of evidence, 4.

Methods:

Data from 9 patients were analyzed for this study. During surgery, a 3.1-mm tantalum bead was sutured to the supraspinatus tendon, medial to the repair site. Glenohumeral kinematics were assessed at 1 week (static) and 3 months (static and during scapular-plane abduction) after surgery using a biplanar videoradiographic system. The 3-dimensional position of the bead was calculated relative to the tendon’s insertion on the humerus (ie, bead-to-insertion distance). Static retraction was calculated as the change in the bead-to-insertion distance under static conditions between 1 week and 3 months after surgery, and maximum dynamic elongation was calculated as the maximal positive change in the bead-to-insertion distance during dynamic motion relative to the start of motion. The magnitudes of static retraction and maximum dynamic elongation were assessed with 1-sample t tests.

Results:

At 3 months after surgery, static retraction occurred in all patients by a mean of 10.0 ± 9.1 mm (P = .01 compared with no elongation). During scapular-plane abduction, maximum dynamic elongation averaged 1.4 ± 1.0 mm (P < .01 compared with no elongation). Descriptively, dynamic elongation consistently took 1 of 2 forms: an initial increase in the bead-to-insertion distance (mean, 2.0 ± 0.6 mm) before decreasing until the end of motion or an immediate and substantial decrease in the bead-to-insertion distance at the onset of motion.

Conclusion:

Repair tissue elongation (static retraction and maximum dynamic elongation) appeared to be a common and significant finding at 3 months after arthroscopic rotator cuff repair. Dynamic elongation of repair tissue during scapular-plane abduction exhibited 1 of 2 distinct patterns, which may suggest different patterns of supraspinatus mechanical and neuromuscular function.