Arthroscopic Rotator Cuff Repair with Double-Row Fixation

The role of injections of mesenchymal stem cells as an augmentation tool in rotator cuff repair: a systematic review

Background

Arthroscopic repair is currently the gold standard for the surgical treatment of rotator cuff tears, but the retear rates remain unacceptably high. Mesenchymal stem cells (MSCs) may play a role in the local biology and enhance tendon-to-bone healing during rotator cuff repair. However, the scientific literature is still not well systematized on the effects of injection of MSCs as an augmentation tool for rotator cuff repair. Our goal was to investigate the effect of injections of MSCs to augment rotator cuff repair in patients with rotator cuff tear.

Methods

PubMed and EMBASE were searched up to June 2022 for clinical studies that applied MSCs injections to augment rotator cuff repair. Imaging, patient-reported outcomes measures, shoulder range of motion and strength were collected. Quantitative synthesis included within- and between-group mean differences with the within-group percentage of minimal clinically important difference for each study and continuous outcomes, and relative risks (RR) for retears and adverse events. Quantitative synthesis was computed with 95% confidence intervals (CIs).

Results

We included 5 studies comprising a total of 228 individuals with a weighted mean age of 59.3 ± 1.2 years. Three studies used bone marrow MSCs and two studies applied adipose-derived MSCs. Patient-reported outcomes measures, shoulder range of motion, and strength improved significantly in all MSCs groups, with minimal clinically important differences ranging from 120% to 679% of established cut-off. When compared to rotator cuff repair alone, the MSCs groups did not result in improved outcomes. The MSCs group showed significant protective effect at the mid-term (RR = 0.52, 95% CI 0.27-0.98) and long-term (RR = 0.24, 95% CI 0.11-0.53).

Conclusion

There are no differences in clinical and functional outcomes between rotator cuff repair with or without augmentation with MSCs. However, there may be a protective effect against retear at the mid-term and long-term follow-up when augmenting the repair with MSCs. The literature on this topic is still preliminary and the quality and certainty of evidence is limited.

Biomechanical Effects of Superior Capsule Reconstruction for Reinforcement of Rotator Cuff Repair in a Degenerated Reparable Supraspinatus Tendon Tear Model

Background

Postoperative retear of the repaired rotator cuff tendon may decrease postoperative shoulder muscle strength, worsen patient outcome, and decrease patient satisfaction. Although superior capsule reconstruction for reinforcement of rotator cuff repair (SCR-R) is reported to prevent postoperative retear, the biomechanical benefit of SCR-R is yet to be explored.

Hypothesis

SCR-R would restore superior glenohumeral stability and decrease subacromial contact pressure in a simulated degenerated supraspinatus tendon tear.

Study Design

Controlled laboratory study.

Methods

Eight fresh-frozen cadaveric shoulders were tested using a custom shoulder-testing system. Subacromial peak contact pressure, glenohumeral superior translation, and glenohumeral range of motion (ROM) were compared for 6 conditions: (1) intact shoulder, (2) traumatic reparable supraspinatus tendon tear model, (3) rotator cuff repair of condition 2, (4) degenerated reparable supraspinatus tendon tear model, (5) rotator cuff repair of condition 4, and (6) SCR-R of condition 4.

Results

Creation of the degenerated reparable supraspinatus tear significantly increased superior glenohumeral translation at 0° (P < .0001) and 30° (P = .003) of glenohumeral abduction. Rotator cuff repair of degenerated reparable supraspinatus tendon tear did not significantly improve superior glenohumeral translation in any abduction position. Compared with that after creation of degenerated reparable supraspinatus tear (condition 4), SCR-R significantly decreased superior glenohumeral translation at 0° (P = .0001), 30° (P = .0002), and 60° (P = .004) of glenohumeral abduction, and significantly decreased subacromial peak contact pressure at 0° (P = .03) and 60° (P = .04) of glenohumeral abduction. Neither rotator cuff repair alone (condition 5) nor SCR-R significantly decreased glenohumeral ROM compared with creating the degenerated reparable supraspinatus tear (condition 4) in any abduction position.

Conclusion

SCR-R completely restored superior glenohumeral translation and subacromial peak contact pressure when the torn tendon had no superior shoulder capsule, as seen in degenerated supraspinatus tendon tear, whereas rotator cuff repair alone did not provide a significant improvement.

Clinical Relevance

SCR-R is recommended for degenerated reparable supraspinatus tendon tear to improve glenohumeral superior stability after surgery.

Dermal Graft Thickness Over 2 mm and Grafts Oriented Parallel to Skin Tension Lines Increased Graft Strength and Suture Retention: A Biomechanical Study

PURPOSE

To assess the variability in graft biomechanical properties of an acellular human dermal matrix patch.

METHODS

A total of 22 strips obtained from 6 separate graft specimens (AlloPatch HD) were tested. Load elongation properties after cyclic loading, including ultimate load at break, energy at break, and extension at break, were tested and compared by graft thickness. Suture pull-out testing using a simple vertical stitch suture retention test was performed.

RESULTS

There was a significant, strong positive correlation between graft thickness and ultimate load to failure, energy at break, and extension at break (P < .01). The association between direction of graft in relation to skin tension lines and ultimate load to failure was also significant (P < .034). The difference in ultimate load to failure from the extremes of graft thickness in this study (1.1 mm vs 3.2 mm) was almost 4-fold (104 N/mm2 vs 402 N/mm2). The suture pull-out testing of 10 dermal graft test strips showed that once the graft thickness reached a threshold thickness of 2 mm, the mode of failure changed from cutting through the graft vertically to tearing the graft diagonally.

CONCLUSIONS

The tested dermal allograft patch shows great variability in thickness within and between individual patches. This study has revealed that grafts thicker than 2 mm and those used in parallel to skin tension lines exhibit a higher ultimate load to failure. Furthermore, graft thickness over 2 mm influenced the method of suture failure.

CLINICAL RELEVANCE

Caution should be exercised when using grafts less than 2 mm due to lower ultimate load to failure and suture pull-out. Marking the patches in accordance with skin tension lines would help determine the ideal orientation of insertion.

The impact of bone marrow stimulation on arthroscopic rotator cuff repair for small to large rotator cuff tears: a randomized controlled trial

BACKGROUND

Bone marrow stimulation (BMS), a procedure involving the creation of multiple channels in the greater tuberosity, is often performed alongside arthroscopic rotator cuff repair (ARCR). This study evaluated the effect of BMS on clinical and structural outcomes following ARCR.

METHOD

This study involved 204 patients with small, medium, and large full-thickness rotator cuff tears. In all, 103 patients who underwent BMS and ARCR made up the BMS group, while the 101 patients who only had ARCR made up the control group with randomization. Clinical and functional outcomes were assessed before and at 3 months, 6 months, 1 year, and 2 years after surgery, using parameters such as range of motion, functional scores (American Shoulder and Elbow Surgeons and Constant score), and clinical scores (Visual Analogue Scale). Tendon integrity was also examined postoperatively via ultrasound at 6 months and 2 years.

RESULTS

There were no significant differences between the two groups concerning range of motion, functional scores (American Shoulder and Elbow Surgeons score and Constant score), and clinical score (Visual Analogue Scale) during the 2-year postsurgery period (all P > .05). Similarly, the rotator cuff retear rate, as assessed using ultrasonographic tendon integrity checks over 2 years postsurgery, did not significantly vary between the groups (all P > .05).

CONCLUSION

There were no significant disparities in functional scores and clinical outcomes between the BMS and control groups. Further, no significant differences were observed in tendon integrity postsurgery. Therefore, the inclusion or exclusion of BMS is not anticipated to influence the postoperative outcome in ARCR for patients with small, medium, or large rotator cuff tears.

Editorial Commentary: Bone Marrow Stimulation and Losartan Augmentation of Shoulder Rotator Cuff Repair

Rotator cuff retear rates after repair have been variously reported as ranging from 5% to 40% for small to mediums tears and as high as 40% to 94% for large to massive tears. Thus strategies to enhance structural healing are relevant. In rabbits, combining oral losartan (which has antifibrotic effects by downregulating transforming growth factor-β1) and bone marrow stimulation (BMS) of the greater tuberosity, showed improved rotator cuff repair pull-out strength and highly organized tendon matrix in a chronic injury model, whereas BMS alone did not improve the mechanical properties. However, clinical studies show that BMS techniques have a positive impact on healing and retear rates. BMS stimulates migration of mesenchymal stem cells from bone marrow to the lesion, and this approach has been widely used to fill cartilage defects by fibrocartilage metaplasia. BMS is a straightforward and cost-effective technique; the use of multiple deeper bone tunnels is recommended.

What is the Optimal Construct to Reduce Failure in Arthroscopic Four Anchor Rotator Cuff Repair?

Background

Re-tear following rotator cuff repair (RCR) is a concerning complication that can lead to poor patient outcomes and necessitate the need for revision surgery. The purpose of our study was to look at the combined construct of knotted vs. knotless medial row and suture vs. suture tape, focusing primarily on re-tear rates following surgery.

Methods

A retrospective observational study of 343 consecutive patients undergoing arthroscopic double row, 4-anchor rotator cuff repair from February 2014 to March 2020 was conducted. Univariate and multivariate statistics were used to assess differences in demographics, comorbidities and tear characteristics between patients who experienced a symptomatic re-tear and those who did not.

Results

The overall symptomatic re-tear rate was 7.6%. Patients who had a knotted medial row repair had a significantly lower rate of re-tear (4.7 vs. 11.3%, p = 0.022). Patients that had a knotted medial row and suture tape repair were significantly less likely to experience a re-tear (OR: 0.180, p = 0.001).

Discussion

The use of suture tape and a knotted medial row repair decreases the incidence of symptomatic re-tear following rotator cuff repair. The combined construct of suture tape and a knotted medial row in rotator cuff repair decreases the risk for symptomatic re-tear following surgery.

Factors associated with healing failure after early repair of acute, trauma-related rotator cuff tears

BACKGROUND

Healing failure after rotator cuff repair is a challenging problem. Acute, trauma-related tears are considered a separate entity and are often treated surgically. The aim of this study was to identify factors associated with healing failure in previously asymptomatic patients with trauma-related rotator cuff tears treated with early arthroscopic repair.

METHODS

This study included 62 consecutively recruited patients (23% women; median age, 61 years; age range, 42-75 years) with acute symptoms in a previously asymptomatic shoulder and a magnetic resonance imaging-verified full-thickness rotator cuff tear after shoulder trauma. All patients were offered, and underwent, early arthroscopic repair, during which a biopsy specimen was harvested from the supraspinatus tendon and analyzed for signs of degeneration. Of the patients, 57 (92%) completed 1-year follow-up and underwent assessment of repair integrity on magnetic resonance images according to the Sugaya classification. Risk factors for healing failure were investigated using a causal-relation diagram where age, body mass index, tendon degeneration (Bonar score), diabetes mellitus, fatty infiltration (FI), sex, smoking, tear location regarding integrity of the rotator cable, and tear size (number of ruptured tendons and tendon retraction) were included and analyzed.

RESULTS

Healing failure at 1 year was identified in 37% of patients (n = 21). A high degree of FI of the supraspinatus muscle (P = .01), a tear location including disruption of rotator cable integrity (P = .01), and old age (P = .03) were associated with healing failure. Tendon degeneration as determined by histopathology was not associated with healing failure at 1-year follow-up (P = .63).

CONCLUSION

Older age, increased FI of the supraspinatus muscle, and a tear including disruption of the rotator cable increased the risk of healing failure after early arthroscopic repair in patients with trauma-related full-thickness rotator cuff tears.

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.

Factors affecting satisfaction in patients with a rotator cuff retear: CT arthrography-based study

PURPOSE

The relationship between retear that may occur after rotator cuff repair and patient satisfaction is not well established. This study aimed to determine whether the types and size of the retear evaluated by computed tomography arthrography (CTA) influenced patient satisfaction. We also analyzed the patient factors that could affect patient satisfaction.

PATIENTS AND METHODS

A total of 50 patients who were diagnosed with rotator cuff retear after undergoing arthroscopic rotator cuff repair were included in this study. All the patients were dichotomously classified into the satisfactory or dissatisfactory groups according to the patients' self-classifications. CTA was used to assess the attachment status of the footprint, detect retear on the medial side of the footprint of the repaired cuff, and determine the retear size. Demographic factors, including sex, age, occupation, dominant upper extremity, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation status, and functional shoulder score, were investigated.

RESULTS

Thirty-nine patients were classified into the satisfactory group and 11 patients were classified into the dissatisfactory group. There were no differences in age, sex, occupation, dominant hand, duration of pain, presence of diabetes mellitus, trauma history, history of ipsilateral shoulder surgery, repair technique, worker's compensation, and duration of follow-up between the two groups. However, the postoperative American Shoulder and Elbow Surgeon (ASES) score (P < 0.01), visual analog scale (VAS) pain level (P < 0.01), anteroposterior (AP) length (P < 0.01), and area of the retear site (P < 0.01) were significantly different.

CONCLUSION

The AP length and area of the retear site estimated using CTA were confirmed as the significant risk factors for dissatisfaction. However, the type of repaired rotator cuff judged by the attachment status of the footprint did not correlate with patient satisfaction. In addition, the postoperative VAS pain scale and ASES score was correlated with patient satisfaction.

Clinical Outcomes of Arthroscopic Revision Rotator Cuff Repair

Aims

Multiple studies have shown excellent clinical results in primary rotator cuff repairs; however, not much evidence is available in the literature on the outcomes of arthroscopic revision rotator cuff repairs. The purpose of this study was to report a cohort of patients who underwent revision arthroscopic rotator cuff repair and identify factors that may influence its outcomes.

Methods

We examined a cohort of 62 patients which underwent revision arthroscopic rotator cuff repair in a single UK institution with a minimum of 24 months follow-up. Active shoulder movements including forward flexion, abduction and external rotation were evaluated, as well as Oxford Shoulder Score (OSS). Further subgroup analysis was performed looking of the effects of age, size of tear, obesity and diabetes mellitus had on clinical outcomes.

Results

59 patients were available for final review. 39 male and 23 were female. The mean age was 64 years. Overall, significant improvements were seen in terms of OSS (p < 0.05), active forward flexion (p < 0.05), active abduction (p < 0.05) and active external rotation (p < 0.05). Our study showed that a significant proportion of patients undergoing arthroscopic revision rotator cuff repair achieve good outcomes. Repairing small- and medium-size tears was successful, diabetics had no post-operative improvements, obese patients achieved significant improvement in range of movement and age was not a predictor of surgical success.

Conclusion

Overall, arthroscopic revision surgery is a successful option; however, appropriate patient selection and counselling is paramount.

Effects of tendon viscoelasticity on the distribution of forces across sutures in a model tendon-to-bone repair

Tears to the rotator cuff often require surgical repair. These repairs often culminate in re-tearing when sutures break through the tendon in the weeks following repair. Although numerous studies have been performed to identify suturing strategies that reduce this risk by balancing forces across sutures, none have accounted for how the viscoelastic nature of tendon influences load sharing. With the aim of providing insight into this problem, we studied how tendon viscoelasticity, tendon stiffness, and suture anchor spacing affect this balancing of forces across sutures. Results from a model of a three-row sutured re-attachment demonstrated that optimized distributions of suture stiffnesses and of the spacing of suture anchors can balance the forces across sutures to within a few percent, even when accounting for tendon viscoelasticity. Non-optimized distributions resulted in concentrated force, typically in the outermost sutures. Results underscore the importance of accounting for viscoelastic effects in the design of tendon to bone repairs.

Alcohol Abuse, Morbid Obesity, Depression, Congestive Heart Failure, and Chronic Pulmonary Disease are Risk Factors for 90-Day Readmission After Arthroscopic Rotator Cuff Repair

Purpose

The purpose of this study was to report the rate and causes of 90-day readmissions after arthroscopic rotator cuff repair.

Methods

A retrospective query from January 2005 to March 2014 was performed using a nationwide administrative claims registry. Patients and complications were identified using International Classification of Disease, Ninth Revision (ICD-9) and Current Procedural Terminology (CPT) codes. Patients who underwent arthroscopic rotator cuff repair (RCR) and were readmitted within 90 days after their index procedure were identified. Patients not readmitted represented controls. Patients readmitted were stratified into separate cohorts depending on the primary cause of readmission, which included cardiac, endocrine, hematological, infectious, gastrointestinal, musculoskeletal (MSK), neoplastic, neurological or psychiatric, pulmonary, and renal. Risk factors assessed were comorbidities comprising the Elixhauser-Comorbidity Index (ECI). Primary outcomes analyzed and compared included cause for readmission, patient demographics, risk factors, in-hospital length of stay (LOS), and costs. Pearson’s chi-square was used to compare patient demographics, and multivariate binomial logistic regression was used to calculate odds ratios (OR) on patient-related risk factors for 90-day readmissions.

Results

10,425 readmitted patients and 301,625 control patients were identified, representing a 90-day readmission rate of 3.5%. The causes of readmissions were primarily related to infectious diseases (15%), MSK (15%), and cardiac (14%) complications. The most common MSK readmissions were osteoarthrosis of the leg or shoulder (24.8%) and spinal spondylosis (8.4%). Multivariate binomial logistic regression analyses demonstrated patients with alcohol abuse (OR, 1.42; P < .0001), morbid obesity (OR, 1.38; P < .0001), depression (OR, 1.35; P < .0001), congestive heart failure (OR, 1.34; P < 0.0001), and chronic pulmonary disease (OR, 1.28; P < .0001) were at the greatest risk of readmissions after RCR.

Conclusions

Significant differences exist among patients readmitted, and those patients who do not require hospital readmission within 90 days following arthroscopic rotator cuff repairs. Readmissions are associated with significant patient comorbidities and were primarily related to medically based complications.

Level of Evidence

Level III, prognostic, retrospective cohort study.

Factors correlated with the optimal tension for arthroscopic rotator cuff repair using Grasper Tensioning Attachment

BACKGROUND

Little is known about the optimal tension in arthroscopic rotator cuff repair (ARCR). This study aimed to identify preoperative, intraoperative, and postoperative factors that correlate with the tension in ARCR and to determine the optimal intraoperative tension using Grasper Tensioning Attachment, a tension meter attached to the common arthroscopic surgical grasper.

METHODS

This study included 63 patients with a mean age at surgery of 65.3 years (range, 45-83 years) who underwent ARCR. The mean follow-up period was 24.1 months (range, 24-28 months). We investigated the patients' demographic data, Japanese Orthopaedic Association score, DeOrio and Cofield classification, and Goutallier stage of the supraspinatus and infraspinatus muscles. We also evaluated cuff integrity based on the Sugaya classification via magnetic resonance imaging. The free edge of the torn retracted tendon was grasped, and the passive tension to the footprint was then measured with Grasper Tensioning Attachment with the arm at the side. The anteroposterior (AP) and mediolateral (ML) diameters were also measured.

RESULTS

The preoperative Goutallier stage of the supraspinatus muscle was stage 0 in 7 cases, stage 1 in 34, stage 2 in 20, and stage 3 in 2. The mean intraoperative rotator repair tension was 10.0 ± 2.5 N (range, 7.5-17 N). The mean AP diameter of the rotator cuff tear was 22 ± 10 mm (range, 8-50 mm), and the mean ML diameter was 24 ± 10 mm (range, 10-50 mm). Age, DeOrio and Cofield classification, Goutallier stage, AP diameter, and ML diameter correlated with rotator repair tension. The rotator repair tension in Sugaya classification type III or IV cases (n = 12, 11.4 ± 2.4 N) was significantly larger than that in type I or II cases (n = 51, 9.7 ± 2.4 N; P = .03). Tension ≥ 10 N as a cutoff value from receiver operating characteristic curve analysis was a risk factor for poor cuff integrity (95% confidence interval, 0.53-0.88).

CONCLUSIONS

Rotator repair tension ≥ 10 N was a risk factor for poor cuff integrity. Thus, care should be taken when performing intraoperative procedures and administering postoperative regimens.

Chitosan-platelet-rich plasma implants improve rotator cuff repair in a large animal model: Pilot study

Freeze-dried formulations of chitosan can be solubilized in platelet-rich plasma (PRP) to form injectable implants that are used as an adjunct treatment during surgical repair of the rotator cuff. The purpose of the current study was to assess chitosan-PRP implant residency, test safety, and assess efficacy over standard-of-care controls in a sheep model of rotator cuff repair. The infraspinatus tendon was transected unilaterally and immediately repaired with suture anchors in 22 skeletally mature ewes. In treatment groups, formulations containing chitosan, trehalose, and calcium chloride were solubilized with autologous leukocyte-rich PRP and injected at the tendon-bone interface and on top of the repaired site (1 mL or 2 mL doses). Implant residency was assessed histologically at 1 day. Outcome measures included MRI assessment at baseline, 6 weeks, and 12 weeks, histopathology and clinical pathology. Chitosan-PRP implants were resident at the injection site at 1 day and induced recruitment of polymorphonuclear cells. The tendon gap, which corresponds to the length of abnormally hyperintense tissue attached to the humeral head, was decreased by treatment with the 2 mL dose when compared to controls at 12 weeks on MRI images. Some histological features were improved by the 2 mL dose treatment compared to controls at 12 weeks. There was no treatment-specific effect on all standard safety outcome measures, which suggests high safety. This study provides preliminary evidence on the safety and efficacy of chitosan-PRP implants in a large animal model that could potentially be translated to a clinical setting.

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.

Relationship between preoperative size of rotator cuff tears measured using radial-slice magnetic resonance images and postoperative rotator cuff integrity: a prospective case-control study

Background

Magnetic resonance imaging (MRI) is useful for diagnosing shoulder diseases preoperatively. However, preoperative risk factors for retears have not been previously reported using a radial-slice MRI. Here, we investigated the relationship between the preoperative tear area of the rotator cuff evaluated using radial-slice MRI and the postoperative rotator cuff integrity. Our hypothesis is that larger tear area of the rotator cuff measured using radial-slice MRI would be associated with increased retear rates.

Methods

From June 2010 to October 2015, we treated 102 consecutive patients who underwent shoulder arthroscopy for reparable rotator cuff tears. The patient demographics, medical comorbidities, radiologic factors, tear size, fatty infiltration, muscle atrophy measured using oblique coronal and oblique sagittal MRI, and the tear area calculated using radial-slice MRI were assessed to compare the intact and retear groups in univariate and multivariate logistic regression analyses. The cutoff values of the independent factors were obtained using the receiver operating characteristic curve.

Results

Retears occurred in 15 of 102 (14.7%) patients. In the univariate analysis, significant differences were found between the two groups for tear size, fatty infiltration of the supraspinatus and infraspinatus, muscle atrophy, and tear area. In the multivariate analysis, the tear area was the independent factor that significantly affected the rate of retear. A tear area of 6.3 cm² was the strongest predictor of retear with an area under the curve of 0.965, sensitivity of 86.7%, and specificity of 96.6%.

Conclusion

The tear area was the independent factor that most significantly affected the rate of retear and showed excellent accuracy with a cutoff value of 6.3 cm². Radial-slice MRI may be a valuable diagnostic tool for assessing the postoperative rotator cuff integrity.

Triple-Row Technique Confers a Lower Retear Rate Than Standard Suture Bridge Technique in Arthroscopic Rotator Cuff Repairs

PURPOSE

To compare the structural and clinical results between the knotless suture bridge (SB) and triple-row (TR) techniques.

METHODS

This study is a retrospective study and included 212 shoulders with repairable rotator cuff tears treated with the SB technique and 206 shoulders treated with the TR technique. In the TR technique, medial and lateral anchors were placed as they would be for the SB technique, with a middle row anchor added on the edge of footprint to reduce the torn tendons. All patients underwent primary arthroscopic rotator cuff repair and had magnetic resonance imaging 6 months postoperatively to evaluate for retear. Sugaya's classification was used to classify the retear pattern. The function of all patients preoperatively and 2 years postoperatively were assessed by the American Shoulder and Elbow Surgeons shoulder index and the University of California at Los Angeles rating scale.

RESULTS

According to Sugaya's classification, 24 (11.3%), 6 (2.8%), and 20 (9.4%) in SB-treated shoulders and 16 (7.8%), 12 (5.8%), and 8 (3.9%) in TR-treated shoulders, respectively had types 3, 4, and 5. There was a statistically significant greater type 5 retear in SB-treated shoulders (P = .038) than in TR-treated shoulders. The average clinical outcome scores at the final follow-up improved significantly relative to those before the surgeries in both groups. There were no statistical differences in the clinical outcome scores at the final follow-up between SB and TR groups.

CONCLUSIONS

The use of the TR technique in arthroscopic rotator cuff repair resulted in a lower large-size retear rate when compared with the use of the SB technique. No clinical differences were noted in the outcomes between the 2 groups.

LEVEL OF EVIDENCE

Level III, therapeutic, retrospective cohort study.

Presurgical tear characteristics and estimated shear modulus as predictors of repair integrity and shoulder function one year after rotator cuff repair

Background

Rotator cuff repair provides pain relief for many patients; however, retears are relatively common and affect approximately 20%-70% of patients after repair. Although magnetic resonance imaging (MRI) offers the ability to assess tissue characteristics such as tear size, retraction, and fatty infiltration, it provides little insight into the quality of the musculotendinous tissues the surgeon will encounter during surgery. However, shear wave elastography (SWE) could provide an indirect assessment of quality (ie, stiffness) by measuring the speed of shear waves propagating through tissue. The objective of this study was to determine the extent to which estimated shear modulus predicts repair integrity and functional outcomes 1 year after rotator cuff repair.

Methods

Thirty-three individuals scheduled to undergo arthroscopic rotator cuff repair were enrolled in this study. Before surgery, shear modulus of the supraspinatus tendon and muscle was estimated using ultrasound SWE. MRIs were obtained before and 1 year after surgery to assess tear characteristics and repair integrity, respectively. Shoulder strength, range of motion, and patient-reported pain and function were assessed before and after surgery. Functional outcomes were compared between groups and across time using a two-factor mixed model analysis of variance. Stepwise regression with model comparison was used to investigate the extent to which MRI and shear modulus predicted repair integrity and function at 1 year after surgery.

Results

At 1 year after surgery, 56.5% of patients had an intact repair. No significant differences were found in any demographic variable, presurgical tear characteristic, or shear modulus between patients with an intact repair and those with a recurrent tear. Compared with presurgical measures, patients in both groups demonstrated significant improvements at 1 year after surgery in pain (P < .01), self-reported function (P < .01), range of motion (P < .01), and shoulder strength (P < .01). In addition, neither presurgical MRI variables (P > .16) nor shear modulus (P > .52) was significantly different between groups at 1 year after surgery. Finally, presurgical shear modulus generally did not improve the prediction of functional outcomes above and beyond that provided by MRI variables alone (P > .22).

Conclusion

Although SWE remains a promising modality for many clinical applications, this study found that SWE-estimated shear modulus did not predict repair integrity or functional outcomes at 1 year after surgery, nor did it add to the prediction of outcomes above and beyond that provided by traditional presurgical MRI measures of tear characteristics. Therefore, it appears that further research is needed to fully understand the clinical utility of SWE for musculoskeletal tissue and its potential use for predicting outcomes after surgical rotator cuff repair.

Stump classification was correlated with retear in the suture-bridge and double-row repair techniques for arthroscopic rotator cuff repair

PURPOSE

The Stump classification is significantly correlated with a retear after arthroscopic rotator cuff repair. However, no study has evaluated whether or not the stump classification is correlated with retear in the suture-bridge or double-row repair techniques. The aim of this study was to evaluate the relationship between a retear and the stump classification in the suture-bridge and double-row repair techniques.

METHODS

Among 389 patients who underwent arthroscopic repairs of full-thickness rotator cuff tears using suture-bridge or double-row repair techniques, 326 patients (median age 67.0 years; range 25-85) were included. There were 51 small, 172 medium, 83 large, and 20 massive tears. Two hundred forty patients were treated with the suture-bridge technique, and 86 patients were treated with the double-row technique. The following variables were analyzed: age, sex, the Cofield classification, anteroposterior and mediolateral tear size on preoperative MRI, global fatty degeneration index, and the stump classification. Cuff integrity was evaluated on magnetic resonance imaging at 6 months after surgery. The patients were divided into the intact and retear groups and the relationship between the variables and retear was evaluated by multivariate logistic regression analysis.

RESULTS

The overall retear rate was 10.1%. In the multivariate logistic regression analysis, the independent predictors of a retear were the stump classification type 3 (Odds ratio: 4.71, p = 0.0246), global fatty degeneration index (Odds ratio: 3.87, p = 0.0030), and anteroposterior tear size (Odds ratio: 1.07, p = 0.0077) in the suture bridge technique. In the double-row technique, the independent predictors of retear were stump classification type 3 (Odds ratio: 7.82, p = 0.0348), and age (Odds ratio: 1.22, p = 0.0163).

CONCLUSION

The stump classification was significantly correlated with retear in the suture-bridge and double-row repair technique. Stump classification type 3 was indicated to be an important risk factor for predicting retear.

LEVEL OF EVIDENCE

III.

Arthroscopic knotless repair: an effective technique for small-sized supraspinatus tendon tears

PURPOSE

The purpose was to evaluate the clinical and radiological results of knotless repair with flat-braided suture in full small-sized supraspinatus tendon tears (< 1 cm).

METHODS

A consecutive series of 54 patients with isolated small supraspinatus tendon tear (< 1 cm and Goutallier index < 2) was evaluated in the study. Patients underwent a knotless arthroscopic repair using flat-braided suture (2 mm wide). Minimal follow-up required was 5 years. Changes in Murley-Constant score, ASES score, strength, and pain relief were assessed. The Sugaya score was used to confirm the tendon repair on MRI. Data were analyzed in two subgroups: technique with additional U point for dog ear deformity (group 1) and technique without additional U point (group 2). The immobilization period was 3 weeks long. Passive mobilization was immediate.

RESULTS

Fifty-four patients were included. Mean age was 57 ± 4 years. The average follow-up was 68 ± 10 months. Average preoperative score of Constant was 51.2 ± 8.5 and 83.1 ± 14.6 at the end of the follow-up (p < 0.001). Mean VAS went from 5.8 ± 1.8 to 1.9 ± 2.1 (p < 0.001). Average forward elevation of the shoulder went from 86.3° ± 9 preoperatively to 169.6° ± 15.9 at the end of the follow-up (p < 0.001). The strength score was significantly higher post-operatively (18.4 vs. 8.3, p < 0.001.). The ASES score was significantly improved 49.1 ± 13.1 vs. 88.6 ± 15.8, p < 0.001). The MRI assessment revealed 94% of Sugaya 1-2. No significant difference was observed between group 1 and 2 regarding all clinical outcomes. Two complex regional pain syndromes were described with a favorable evolution. Three patients presented a retear requiring an iterative arthroscopic repair.

CONCLUSION

The use of a knotless arthroscopic construct with flat-braided suture for small supraspinatus repair achieved excellent structural and clinical results. This technique is fully adequate for the arthroscopic treatment of such tears, enabling early mobilization.

LEVEL OF EVIDENCE

Level III.

Joining soft tissues to bone: Insights from modeling and simulations

Entheses are complex multi-tissue regions of the musculoskeletal system serving the challenging task of connecting highly dissimilar materials such as the compliant tendon to the much stiffer bone, over a very small region. The first aim of this review is to highlight mathematical and computational models that have been developed to investigate the many attachment strategies present at entheses at different length scales. Entheses are also relevant in the medical context due to the high prevalence of orthopedic injuries requiring the reattachment of tendons or ligaments to bone, which are associated with a rather poor long-term clinical outcome. The second aim of the review is to report on the computational works analyzing the whole tendon to bone complex as well as targeting orthopedic relevant issues. Modeling approaches have provided important insights on anchoring mechanisms and surgical repair strategies, that would not have been revealed with experiments alone. We intend to demonstrate the necessity of including, in future models, an enriched description of enthesis biomechanical behavior in order to unravel additional mechanical cues underlying the development, the functioning and the maintaining of such a complex biological interface as well as to enhance the development of novel biomimetic adhesive, attachment procedures or tissue engineered implants.

Assessment of postoperative acromial and subacromial morphology after arthroscopic acromioplasty using magnetic resonance imaging

OBJECTIVE

To identify the morphological characteristics of the acromion and subacromial bursal space after arthroscopic acromioplasty using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

One hundred patients who received arthroscopic rotator cuff repair and acromioplasty each received at least three MRI examinations (preoperative, first immediate postoperative, and second follow-up imaging between 8 months and 1 year postoperatively). Changes over time in the thickness and morphology of the postoperative acromion as well as the subacromial bursal space were assessed. Clinical and radiological parameters were also analyzed to identify any association with changes in acromial morphology.

RESULTS

Despite minimal acromial thinning observed at the first immediate postoperative state, the acromions showed significant thinning at the second postoperative MRI, with a mean reduction of 32%. Along with acromial thinning, an exaggerated concave contour of the acromial undersurface was observed in some patients. In the subacromial space, a loculated fluid collection developed in 91% of the patients at the second postoperative follow-up. No statistically significant association was noted between postoperative acromial thickness change and clinical or radiological factors (P value > 0.05).

CONCLUSION

A significant delayed reduction in acromial thickness within approximately 1 year of arthroscopic acromioplasty is thought to be a normal postoperative feature. The simultaneous collection of a loculated, cyst-like fluid in the subacromial bursal space may be an important associated factor of postoperative acromial thinning.

The Top 50 Most-Cited Shoulder Arthroscopy Studies

Purpose

To determine the 50 most frequently cited studies in the orthopaedic shoulder arthroscopy literature and to conduct a bibliometric analysis of these studies.

Methods

The Clarivate Analytics Web of Knowledge database was used to gather data and metrics using Boolean queries to capture all possible iterations of shoulder arthroscopy research. The search list was sorted so that articles were organized in descending order based on the number of citations and included or excluded based on relevance to shoulder arthroscopy. The information extracted for each article included author name, publication year, country of origin, journal name, article type, and the level of evidence.

Results

For these 50 studies, the total number of citations was calculated to be 13,910, with an average of 278.2 citations per paper. The most-cited article was cited 1134 times, whereas the second- and third-most cited articles were cited 920 and 745 times, respectively. All 50 articles were published in English and came from 7 different orthopaedic journals. The United States was responsible for most of the included articles (31), followed by France (9) and Japan (3).

Conclusions

The majority of the most-cited articles in shoulder arthroscopy are case series and descriptive studies originating from the United States. In addition, more than one half of the top 50 most-cited studies were published after 2004, which suggests that article age may be less important in the accumulation of citations for a rapidly growing field like shoulder arthroscopy.

Clinical Relevance

The top 50 most-cited studies list will provide researchers, medical students, residents, and fellows with a foundational list of the most important and influential academic contributions to shoulder arthroscopy.

Prospective study of tendon healing and functional gain after arthroscopic repair of isolated supraspinatus tear

INTRODUCTION

In case of failure of non-operative treatment of isolated supraspinatus tear, tendon surgery can improve shoulder function and alleviate pain. The present study hypothesis was that isolated supraspinatus repair shows good healing, with improved clinical results.

MATERIALS AND METHODS

A prospective multicentre study followed up 199 patients (mean age, 57 years) for one year. Inclusion criteria comprised: isolated full-thickness supraspinatus tear, retraction grade<3, with the same double-row arthroscopic technique. Clinical assessment used Constant score at 6 weeks and 3, 6 and 12 months. Ultrasound control checked tendon repair quality on the Sugaya criteria, types I-II-III being considered as healed.

RESULTS

At one year, mean Constant score had increased by 26 points (p<0.001). Healing rate was 94% (n=187): Sugaya type I, 46% (n=92); type II, 41% (n=81); type III, 7% (n=14). Mean Constant score was significantly higher in case of healing: 81 vs. 70 points (p=0.002). Constant score progression was identical in both healing groups throughout follow-up. Univariate analysis showed no correlation between epidemiological or tear-related factors and tendon healing.

CONCLUSION

Arthroscopic repair of isolated small supraspinatus tear provided 94% healing. Clinical results were better when healing was achieved.

LEVEL OF EVIDENCE

I, prospective cohort study.

Bone Marrow Stimulation in Arthroscopic Repair for Large to Massive Rotator Cuff Tears With Incomplete Footprint Coverage

BACKGROUND

There is no research on incomplete footprint coverage with single-row repair related to bone marrow stimulation (BMS) in large to massive rotator cuff tears (RCTs).

PURPOSE/HYPOTHESIS

The purpose was to compare the clinical results and structural integrity between BMS and non-BMS groups that underwent arthroscopic repair of large to massive rotator cuff tears with <50% footprint coverage. It was hypothesized that both groups would exhibit improved clinical outcomes at 2 years after surgery but the BMS group would have significantly better clinical outcomes and structural integrity.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

This study included 98 patients who underwent arthroscopic repair with <50% footprint coverage for large to massive RCTs with (BMS group; n = 56) or without (non-BMS group; n = 42) BMS. Functional outcomes at the 2-year follow-up were assessed using the visual analog scale for pain score, subjective shoulder value; American Shoulder and Elbow Surgeons score; University of California, Los Angeles, shoulder score; and active range of motion. Structural integrity was evaluated using magnetic resonance arthrography or computed tomography arthrography results at 6 months postoperatively.

RESULTS

At the 2-year follow-up, all functional outcomes significantly improved in both groups compared with preoperative values (P < .001). However, there were no significant postoperative differences between groups. On follow-up magnetic resonance arthrography or computed tomography arthrography, the overall retear rate was not significantly different between the BMS group (30.3%; 17/56) and the non-BMS group (35.7%; 15/42).

CONCLUSION

While both groups exhibited functional improvement after single-row repair with <50% footprint coverage for large to massive RCTs, BMS did not produce better clinical outcomes or structural integrity.

Separate double-layer repair versus en masse repair for delaminated rotator cuff tears: a systematic review and meta-analysis

OBJECTIVE

Delaminated rotator cuff tears are a common shoulder disorder in elderly individuals. Either arthroscopic separate double-layer repair (DR) or en masse repair (ER) is used to treat a delaminated rotator cuff tear. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic ER versus DR intervention.

METHODS

Five studies were acquired from PubMed, Medline, Embase, CNKI, Google, and the Cochrane Library. The data were extracted by two of the coauthors independently and were analyzed with RevMan 5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. The Cochrane Collaboration's risk of bias tool and Newcastle-Ottawa Scale were used to assess the risk of bias.

RESULTS

Five studies, including two randomized controlled trials (RCTs) and three observational studies, were assessed. The methodological quality of the trials ranged from low to high. The pooled results for the Shoulder Rating Scale of the University of California at Los Angeles (UCLA) score, visual analog scale (VAS) score, Constant score, and range of motion (ROM) showed that the outcomes were not statistically significant between the two interventions. The difference in retear rate was not statistically significant (OR = 0.69, 95% CI = 0.36-1.33, P = 0.27). The sensitivity analysis proved the stability of the pooled results, and publication bias was not apparent.

CONCLUSIONS

Both arthroscopic ER and DR interventions had benefits in delaminated rotator cuff tear treatment. ER and DR treatments were equally effective and had the same retear rate. The arthroscopic DR technique could not be recommended as the optical choice for delaminated rotator cuff tears based on current evidence.

Surgical or nonsurgical treatment for nontraumatic rotator cuff tears: Study protocol clinical trial

BACKGROUND

The optimal treatment for symptomatic, nontraumatic rotator cuff tear is unknown. The primary aim of this randomized controlled trial is to compare functional improvement after surgical and conservative treatment of nontraumatic rotator cuff tears.

METHODS

This is a single-centre, randomized clinical trial with a follow-up of 12 months. Patients older than 18 years with magnetic resonance imaging - confirmed nontraumatic rotator cuff tears that are suitable for either surgery or nonsurgery treatment is enrolled. The primary outcome is Constant score. Secondary outcome measures include visual analog scale (VAS) score, patient satisfaction, and American Shoulder and Elbow Surgeons (ASES) score. All scores are assessed by an independent observer who is blinded to the allocation of groups.

RESULTS

The study will provide much needed data on surgical vs nonsurgical treatment for nontraumatic rotator cuff tears. Results of this study may help patients, clinicians, and policy makers assess the pivotal question on comparative effectiveness of surgery vs nonsurgical for rotator cuff tears.

TRIAL REGISTRATION

This study protocol was registered in Research Registry (researchregistry5442).

Defining massive rotator cuff tears: a Delphi consensus study

BACKGROUND

A standard definition for massive rotator cuff tears (MRCTs) has not been identified. The purpose of this study is to use the modified Delphi technique to determine a practical, consensus definition for MRCTs.

METHODS

This study is based on responses from 20 experts who participated in 4 rounds of surveys to determine a consensus definition for MRCT. Consensus was achieved when at least 70% of survey responders rated an item at least a 4 on a 5-point scale. A set of core characteristics was drafted based on literature review and then refined to achieve a consensus MRCT definition.

RESULTS

The following core characteristics reached consensus in the first round: tear size, number of tendons torn, and degree of medial retraction. Magnetic resonance imaging (MRI) and intraoperative findings reached consensus as the modalities of diagnosis. The second round determined that tear size should be measured as a relative value. An initial definition for MRCT was proposed in the third round: retraction of tendon(s) to the glenoid rim and/or a tear with ≥67% greater tuberosity exposure (65% approval). A modified definition was proposed that specified that degree of retraction should be measured in the coronal or axial plane and that the amount of greater tuberosity exposure should be measured in the sagittal plane (90% approval).

CONCLUSIONS

This study determined with 90% agreement that MRCT should be defined as retraction of tendon(s) to the glenoid rim in either the coronal or axial plane and/or a tear with ≥67% of the greater tuberosity exposed measured in the sagittal plane. The measurement can be performed either with MRI or intraoperatively.

Surgical Options for Failed Rotator Cuff Repair, except Arthroplasty: Review of Current Methods

Although the prevalence of rotator cuff tears is dependent on the size, 11% to 94% of patients experience retear or healing failure after rotator cuff repair. Treatment of patients with failed rotator cuff repair ranges widely, from conservative treatment to arthroplasty. This review article attempts to summarize the most recent and relevant surgical options for failed rotator cuff repair patients, and the outcomes of each treatment, except arthroplasty.

The arthroscopic triple-row modified suture bridge technique for rotator cuff repair: functional outcome and repair integrity

BACKGROUND

The optimal technique for arthroscopic rotator cuff repair is still controversial. Large tears with a high grade of retraction have an especially high risk of retearing. This study reports the clinical and radiologic results of a triple-row modified suture bridge technique for the treatment of full-thickness rotator cuff tears with medium and high grades of retraction.

METHODS

A total of 101 shoulders in 100 patients underwent a triple-row modified suture bridge reconstruction for full-thickness rotator cuff tears with retraction grade II and grade III according to Patte; 81 patients were reached for follow-up 36.2 months after surgery. At follow-up, clinical outcome was assessed by the American Shoulder and Elbow Surgeons score, subjective shoulder value, visual analog scale score, University of California-Los Angeles shoulder score, and Constant score (CS). At follow-up, an ultrasound examination was performed to determine tendon integrity or retears in all patients.

RESULTS

The overall retear rate was 4.9% (4/81). The clinical outcome was good to excellent (American Shoulder and Elbow Surgeons score, 94 ± 11; subjective shoulder value, 92 ± 12; University of California-Los Angeles shoulder score, 33 ± 5; Constant score, 90 ± 9). In the radiologic follow-up, no retear was found in any of the follow-up patients after an average of 36.2 months. There was no significant difference in clinical outcome parameters between rotator cuff tears Patte II and Patte III (P > .05).

CONCLUSION

For tears with a high grade of retraction, surgical treatment using a triple-row modified suture bridge technique represents a good treatment option with a low rate of retearing and good to excellent clinical results.

Gap formation after single lateral row versus dual-row suture bridge cuff repair: An ovine biomechanical model

BACKGROUND

The aim of this study is to compare two types of suture bridging constructs; a laterally based bridging single row (SR) construct and a classic dual row (DR) suture bridge construct. The hypothesis is that the DR construct will demonstrate superior biomechanical properties.

METHODS

Six matched pairs of sheep infraspinatus tendon tears repaired with these two different types of suture bridging techniques were tested for gap formation, ultimate failure load and mode of failure. The specimens were pre-cycled for 10 cycles before they were subjected to a constant pre-load of 10N. The specimens were then subjected to cyclic loading at a speed of 8.33 mm/s. The test was stopped after every 500 cycles for a total of 3000 cycles.

RESULTS

Mean gap formation after 3000 cycles was lower in the DR group (0.81 ± 0.2 mm versus 2.44 ± 0.27 mm; p = 0.002). Mean change in gap (with every 500 cycles) was also lesser for the DR group after 1500 cycles. DR repairs failed at a higher load (523.4 ± 80.4 N) compared to the SR repairs (452.3 ± 66.3 N) but this did not reach significance. All repairs failed with sutures pulling through the tendon during load to failure testing.

CONCLUSIONS

Gap formation is significantly lower with a dual row suture bridge construct than a laterally based bridging single row construct.

LEVEL OF EVIDENCE

Biomechanical study.

The Association of Osteoporosis and Bisphosphonate Use With Revision Shoulder Surgery After Rotator Cuff Repair

PURPOSE

To examine any association between osteoporosis and the failure of arthroscopic rotator cuff repair (ARCR) leading to revision surgery and to investigate whether the use of bisphosphonates had any influence on the observed associations.

METHODS

Patients who underwent ARCR with a diagnosis of osteoporosis were identified from the PearlDiver database and stratified according to whether there was a filled prescription for a bisphosphonate in the perioperative period. Patients with osteoporosis who underwent ARCR with bisphosphonate use were compared with age- and sex-matched patients who underwent ARCR with osteoporosis without a prescription for a bisphosphonate within 1 year of surgery and patients who underwent ARCR without a diagnosis of osteoporosis and no bisphosphonate use. The primary outcome measure was ipsilateral revision rotator cuff surgery, including revision repair, debridement for a diagnosis of a rotator cuff tear, or reverse shoulder arthroplasty. A multivariable logistic regression analysis was used to control for patient demographic characteristics and comorbidities during comparisons.

RESULTS

We identified 2,706 patients, including 451 in the bisphosphonate study group; 902 in the osteoporosis, no-bisphosphonate control group; and 1,353 in the non-osteoporosis control group. Patients with osteoporosis, including those to whom bisphosphonates were prescribed, had a significantly higher rate of revision rotator cuff surgery (6.58%) than patients without osteoporosis (4.51%) (odds ratio, 1.60; 95% confidence interval, 1.30-1.97; P = .008). No significant difference in the rate of revision surgery was found between patients with osteoporosis using bisphosphonates (6.65%) and age- and sex-matched patients with osteoporosis not using bisphosphonates (6.54%, P = .718).

CONCLUSIONS

By using an administrative database, this study was able to show a substantial difference in the revision surgery rate after ARCR in patients with osteoporosis compared with matched controls.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

At a 10-Year Follow-up, Tendon Repair Is Superior to Physiotherapy in the Treatment of Small and Medium-Sized Rotator Cuff Tears

BACKGROUND

Tendon repair and physiotherapy are frequently used treatment methods for small and medium-sized rotator cuff tears. In 2 previous publications of the 1 and 5-year results of this study, we reported significant but small between-group differences in favor of tendon repair. Long-term results are needed to assess whether the results in both groups remain stable over time.

METHODS

In this study, 103 patients with a rotator cuff tear not exceeding 3 cm were randomly assigned to primary tendon repair or physiotherapy with optional secondary repair. Blinded follow-up was performed after 6 months and 1, 2, 5, and 10 years. Outcome measures included the Constant score; the self-report section of the American Shoulder and Elbow Surgeons score; the measurement of shoulder pain, motion, and strength; and patient satisfaction. Magnetic resonance imaging (MRI) was performed on surgically treated shoulders after 1 year, and ultrasound was performed on all shoulders after 5 and 10 years. The main analysis was by 1-way analysis of covariance and by intention to treat.

RESULTS

Ninety-one of 103 patients attended the last follow-up. After 10 years, the results were better for primary tendon repair, by 9.6 points on the Constant score (p = 0.002), 15.7 points on the American Shoulder and Elbow Surgeons score (p < 0.001), 1.8 cm on a 10-cm visual analog scale for pain (p < 0.001), 19.6° for pain-free abduction (p = 0.007), and 14.3° for pain-free flexion (p = 0.01). Fourteen patients had crossed over from physiotherapy to secondary surgery and had an outcome on the Constant score that was 10.0 points inferior compared with that of the primary tendon repair group (p = 0.03).

CONCLUSIONS

At 10 years, the differences in outcome between primary tendon repair and physiotherapy for small and medium-sized rotator cuff tears had increased, with better results for primary tendon repair.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Fibroblast Growth Factor 2 Enhances Tendon-to-Bone Healing in a Rat Rotator Cuff Repair of Chronic Tears

BACKGROUND

The effects of fibroblast growth factor 2 (FGF-2) on healing after surgical repair of chronic rotator cuff (RC) tears remain unclear.

HYPOTHESIS

FGF-2 enhances tenogenic healing response, leading to biomechanical and histological improvement of repaired chronic RC tears in rats.

STUDY DESIGN

Controlled laboratory study.

METHODS

Adult male Sprague-Dawley rats (n = 117) underwent unilateral surgery to refix the supraspinatus tendon to its insertion site 3 weeks after detachment. Animals were assigned to either the FGF-2 group or a control group. The effects of FGF-2 were assessed via biomechanical tests at 3 weeks after detachment and at 6 and 12 weeks postoperatively and were assessed histologically and immunohistochemically for proliferating cell nuclear antigen and mesenchymal stem cell (MSC)-related markers at 2, 6, and 12 weeks postoperatively. The expression of tendon/enthesis-related markers, including SRY-box 9 (Sox9), scleraxis (Scx), and tenomodulin (Tnmd), were assessed by real-time reverse transcription polymerase chain reaction, in situ hybridization, and immunohistochemistry. The effect of FGF-2 on comprehensive gene expressions at the healing site was evaluated by microarray analysis.

RESULTS

The FGF-2 group showed a significant increase in mechanical strength at 6 and 12 weeks compared with control; the FGF-2 group also showed significantly higher histological scores at 12 weeks than control, indicating the presence of more mature tendon-like tissue. At 12 weeks, Scx and Tnmd expression increased significantly in the FGF-2 group, whereas no significant differences in Sox9 were found between groups over time. At 2 weeks, the percentage of positive cells expressing MSC-related markers increased in the FGF-2 group. Microarray analysis at 2 weeks after surgery showed that the expression of several growth factor genes and extracellular matrix-related genes was influenced by FGF-2 treatment.

CONCLUSION

FGF-2 enhanced the formation of tough tendon-like tissues including an increase in Scx- or Tnmd-expressing cells at 12 weeks after surgical repair of chronic RC tears. The increase in mesenchymal progenitors and the changes in gene expression upon FGF-2 treatment in the early phase of healing appear to be related to a certain favorable microenvironment for tenogenic healing response of chronic RC tears.

CLINICAL RELEVANCE

These findings may provide advantages in therapeutic strategies for patients with RC tears.

Comparison of arthroscopic suture-bridge technique and double-row technique for treating rotator cuff tears: A PRISMA meta-analysis

BACKGROUND

Rotator cuff tear is a common shoulder disorder in the elderly. Either arthroscopic double-row (DR) or suture-bridge (SB) technique for rotator cuff tear patients is needed to choose. We conducted this systematic review and meta-analysis to compare the clinical outcomes of arthroscopic SB versus DR intervention.

METHODS

The 7 studies were acquired from PubMed, Medline, Embase, CNKI, Google, and Cochrane Library. The data were extracted by 2 of the co-authors independently and were analyzed by RevMan5.3. Mean differences (MDs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle-Ottawa scale were used to assess risk of bias.

RESULTS

Seven studies including 1 randomized controlled trial and 6 observational studies were assessed. The methodological quality of the trials ranged from low to moderate. The pooled results of American Shoulder and Elbow Surgeons score, Constant score, visual analog scale score, and range of motion showed that the differences were not statistically significant between the 2 interventions. The difference of University of California at Los Angeles (UCLA) score was statistically significant between SB and DR intervention, and SB treatment was more effective (MD = -0.95, 95% CI = -1.70 to -0.20, P = .01). The difference of re-tear rate was statistically significant and SB treatment achieved better result than DR treatment (OR = 0.31, 95% CI = 0.15-0.64, P = .001). Sensitivity analysis proved the stability of the pooled results and the publication bias was not apparent.

CONCLUSIONS

Both arthroscopic SB and DR interventions had benefits in rotator cuff tear. SB treatment was more effective in UCLA score and had lower re-tear rate than DR treatment. The arthroscopic SB technique is recommended as the optical choice for rotator cuff tear.

Bone marrow stimulation decreases retear rates after primary arthroscopic rotator cuff repair: a systematic review and meta-analysis

BACKGROUND

Despite the optimization of biomechanical and patient factors in the setting of rotator cuff repair (RCR), postoperative retear rates remain high in many series reported in the literature. Preclinical studies have suggested bone marrow stimulation (BMS) at the rotator cuff footprint may reduce the rate of retear after RCR. The objective of this meta-analysis was to analyze the clinical evidence investigating the effect of arthroscopic RCR, with and without BMS, on rotator cuff healing and functional outcomes.

METHODS

PubMed, MEDLINE, Embase, and the Cochrane Library were searched through December 2017. Two reviewers selected studies based on the inclusion criteria and assessed methodologic quality. Pooled analyses were performed for continuous and binomial variables where appropriate.

RESULTS

Four studies (365 patients), including 2 Level I randomized controlled trials and 2 Level III retrospective comparative cohort studies were included. There was no statistical difference in the Disabilities of the Arm, Shoulder and Hand score, University of California Los Angeles Shoulder Rating Scale score, or the Constant score between the BMS and conventional repair groups. The pooled retear rates were 18.4% (28 of 152) and 31.8% (56 of 176) for patients treated with and without BMS, respectively. The pooled analysis of rotator cuff retear rates from the 4 studies (328 patients) showed a statistically significant difference favoring BMS over conventional repair (odds ratio, 0.42; 95% confidence interval, 0.25-0.73; P = .002; I² = 0%).

CONCLUSION

BMS reduces the retear rate after RCR but shows no difference in functional outcomes compared with conventional repair. This study provides evidence for the use of BMS as a potential cost-effective biological approach toward improving rotator cuff healing.

Superior Capsule Reconstruction for Reinforcement of Arthroscopic Rotator Cuff Repair Improves Cuff Integrity

BACKGROUND

Retear of repaired rotator cuff tendons worsens patient outcome and decreases patient satisfaction. Superior capsule reconstruction (SCR) was developed to center the humeral head and thus restore the force couple for patients with rotator cuff tears.

PURPOSE

To evaluate whether SCR for reinforcement before arthroscopic rotator cuff repair (ARCR) improves cuff integrity.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Thirty-four consecutive patients (mean age, 69.1 years) with severely degenerated but reparable rotator cuff tears underwent SCR with fascia lata autografts for reinforcement before ARCR. All tears were medium (1-3 cm) or large (3-5 cm), and the number of torn tendons was 2 (supraspinatus and infraspinatus) in 29 shoulders and 3 (supraspinatus, infraspinatus, subscapularis) in 5 shoulders. To assess the benefit of SCR for reinforcement, all data were compared with those after ARCR alone among 91 consecutive patients with medium or large rotator cuff tears (mean age, 63.6 years). The American Shoulder and Elbow Surgeons (ASES) and Japanese Orthopaedic Association (JOA) scores, active shoulder range of motion, and cuff integrity (Sugaya magnetic resonance imaging classification) were compared ( t test and chi-square test) between ARCR with and without SCR, as well as before surgery and at final follow-up.

RESULTS

All 34 patients who underwent SCR before ARCR had neither postoperative retear nor type III cuff integrity, whereas those treated with ARCR alone had a 4% incidence (4 of 91) of retear and 8% incidence of type III cuff integrity. ASES and JOA scores, active elevation, active external rotation, and active internal rotation increased in both treatment groups ( P < .001). Postoperative ASES score and active range of motion did not differ between groups, although the Goutallier grade of the supraspinatus was higher for ARCR with SCR (mean, 2.8) than ARCR alone (mean, 2.1; P < .0001).

CONCLUSION

SCR for reinforcement prevented retear at 1 year after ARCR and improved the quality of the repaired tendon on magnetic resonance imaging. Functional outcomes were similar between groups, even though degeneration of the torn tendons was greater among patients who underwent ARCR with SCR.

Arthroscopic double-row rotator cuff repair: a comprehensive review of the literature

Rotator cuff repairs seek to achieve adequate tendon fixation and to secure the fixation during the process of biological healing. Currently, arthroscopic rotator cuff repair has become the gold standard. One of the earliest defined techniques is single-row repair but the inadequacy of single-row repair to precisely restore the anatomical footprint as well as the significant rates of retear especially in large tears have led surgeons to seek other techniques. Double-row repair techniques, which have been developed in response to these concerns, have various modifications like the number and placement of anchors and suture configurations.

When the literature is reviewed, it is possible to say that double-row repairs demonstrate superior biomechanical properties. In regard to retear rates, both double row and transosseous equivalent (TOE) techniques have also yielded more favorable outcomes compared to single-row repair. But the clinical results are conflicting and more studies have to be conducted. However, it is more probable that superior structural integrity will yield better structural and functional results in the long run. TOE repair technique is regarded as promising in terms of better biomechanics and healing since it provides better footprint contact. Knotless TOE structures are believed to reduce impingement on the medial side of tendons and thus aid in tendon nutrition; however, there are not enough studies about its effectiveness.

It is important to optimize the costs without endangering the treatment of the patients. We believe that the arthroscopic TOE repair technique will yield superior results in regard to both repair integrity and functionality, especially with tears larger than 3 cm. Although defining the pattern of the tear is one of the most important guiding steps when selecting the repair technique, the surgeon should not forget to evaluate every patient individually for tendon healing capacity and functional expectations.

Rotator cuff repair with all-suture anchors: a midterm magnetic resonance imaging evaluation of repair integrity and cyst formation

BACKGROUND

This study investigated the feasibility and safety of all-suture anchors in arthroscopic rotator cuff repair.

METHODS

All patients were diagnosed with a rotator cuff tear by ultrasound or magnetic resonance imaging (MRI). Patients with partial tears, massive tears, subscapularis tears, or previous shoulder surgery, were excluded. MRI and clinical outcome were investigated in all patients at 1.58 years (range, 1.0-2.0 years) after rotator cuff repair with all-suture anchors (prospective case series). Integrity of the cuff repair, cyst formation (encapsulated fluid signal around the anchor), ingrowth of the bone into the anchor, and integrity of the bone tunnel border were evaluated for 47 anchors. Clinical results were evaluated using the Constant-Murley score.

RESULTS

An MRI evaluation was performed in 20 patients at 1.58 years (range, 1.0-2.0 years) after rotator cuff repair with all-suture anchors. MRI evaluation showed a very small rim of fluid around 10% of the anchors. None of the anchors showed cyst formation with fluid diameter more than twice the anchor diameter. In approximately 90% of the anchors, no fluid could be detected between the anchors and the edge of the bony tunnel. Full rotator cuff integrity was seen in 19 patients. Only 1 patient sustained a retear. Clinical results comparable with an arthroscopic rotator cuff repair using classic anchors were seen.

CONCLUSIONS

This prospective clinical cohort study shows promising early radiographic and clinical results after arthroscopic rotator cuff repair using all-suture anchors.

Double-Layer Rotator Cuff Repair: Anatomic Reconstruction of the Superior Capsule and Rotator Cuff Improves Biomechanical Properties in Repairs of Delaminated Rotator Cuff Tears

BACKGROUND

Delamination in rotator cuff tears has been identified as a prognostic factor for negative outcome after repair, with a reported prevalence between 38% and 88%.

PURPOSE

To compare biomechanical properties of 3 repair techniques for delaminated rotator cuff tears.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eighteen fresh-frozen cadaveric shoulders were used to evaluate rotator cuff footprint reconstruction, contact area and pressure, displacement under cyclical loading, and load to failure of 3 double-row repair configurations: double-row suture repair with medial row knots (medially knotted bridge, mkB); knotless double-row repair using suture tapes (knotless bridge, klB); and knotless double-row, double-layer-specific repair (double-layer, DL). Dynamic pressure sensors were used to assess contact patterns at the footprint region in 0°, 30°, and 60° of glenohumeral abduction and 5 rotational positions (0°, 30° of internal rotation, 30° of external rotation, 60° of internal rotation, 60° of external rotation). Optical markers were used to document whole tendon and individual layer displacement after rotator cuff repair under cyclical loading for 200 cycles (10 N to 100 N at 1 Hz). Specimens were then loaded monotonically to failure at a rate of 33 mm/min.

RESULTS

Mean contact area and footprint restoration were highest in the DL group at 60° of glenohumeral abduction for all rotational positions (mkB mean ± SD, 195.4 ± 54.3 mm², 66.7% ± 19.7%; klB, 250.6 ± 34.9 mm², 76.2% ± 10.3%; DL, 318.4 ± 36.6 mm², 109.1% ± 24.0%; P < .001). The double-layer-specific repair showed the least displacement under cyclical loading (mkB mean ± SD, 0.53 ± 0.18 mm; klB, 0.79 ± 0.37 mm; DL, 0.31 ± 0.24 mm; P = .029), most closely resembling the native tendon. Peak loads at failure were comparable between repair groups (mkB mean ± SD, 366.92 ± 70.59 N; klB, 280.05 ± 77.66 N; DL, 398.35 ± 109.04 N; P = .083).

CONCLUSION

Anatomic restoration of the superior capsular and tendon insertion in delaminated rotator cuff tears with a double-layer-specific repair configuration demonstrated superior footprint restoration with increasing abduction, while providing construct displacement comparable to the native tendon under cyclical loading. Peak load at failure was comparable between repair constructs.

CLINICAL RELEVANCE

The prevalence and clinical importance of delaminated rotator cuff tears have long been underestimated. Anatomically correct individual reconstruction of the superior capsule and rotator cuff could restore near-native biomechanics and potentially reduce the risk of rotator cuff repair failure.

Does structural integrity following rotator cuff repair affect functional outcomes and pain scores? A meta-analysis

BACKGROUND

To assess whether the integrity of rotator cuff repairs has an impact on functional outcomes, as well as pain scores, after surgery.

METHODS

Systematic review and meta-analyses performed for Level Ι, ΙΙ and ΙΙΙ studies that presented functional outcome scores and radiological assessment of integrity following rotator cuff repair. Extracted data included patient demographics, functional outcome scores [Constant Score, University of California at Los Angeles (UCLA) shoulder score, American Shoulder and Elbow Surgeons (ASES) shoulder score, visual analogue scale (VAS) Pain score], as well as assessment of repair integrity on radiological investigations. A meta-analysis was performed using weighted means and a random effects model.

RESULTS

Twelve studies were included in the final analysis. Average re-tear rate for the 800 included patients was 22% at a mean follow-up of 27.5 months after surgery. Patients with intact repairs had a significantly higher Constant Score (8.61 points, p < 0.00001), UCLA shoulder score (2.96 points, p < 0.0001) and ASES shoulder score (9.49 points, p < 0.0006). Patients with intact repairs also reported lower pain VAS Pain scores by 0.62 points (p < 0.0004).

CONCLUSIONS

Our results show better functional outcome and pain scores in patients with intact rotator cuffs at follow-up when compared to those that have re-torn. This difference is equivalent to the published Minimal Clinically Important Difference for the ASES but not Constant Scores. This review has also highlighted that shoulder strength in patients with intact cuff repairs is likely to be greater than in patients with a failed repair.

Bone marrow mesenchymal stem cells do not enhance intra-synovial tendon healing despite engraftment and homing to niches within the synovium

Background

Intra-synovial tendon injuries display poor healing, which often results in reduced functionality and pain. A lack of effective therapeutic options has led to experimental approaches to augment natural tendon repair with autologous mesenchymal stem cells (MSCs) although the effects of the intra-synovial environment on the distribution, engraftment and functionality of implanted MSCs is not known. This study utilised a novel sheep model which, although in an anatomically different location, more accurately mimics the mechanical and synovial environment of the human rotator cuff, to determine the effects of intra-synovial implantation of MSCs.

Methods

A lesion was made in the lateral border of the lateral branch of the ovine deep digital flexor tendon within the digital sheath and 2 weeks later 5 million autologous bone marrow MSCs were injected under ultrasound guidance into the digital sheath. Tendons were recovered post mortem at 1 day, and 1–2, 4, 12 and 24 weeks after MSC injection. For the 1-day and 1–2-week groups, MSCs labelled with fluorescent-conjugated magnetic iron-oxide nanoparticles (MIONs) were tracked with MRI, histology and flow cytometry. The 4, 12 and 24-week groups were implanted with non-labelled cells and compared with saline-injected controls for healing.

Results

The MSCs displayed no reduced viability in vitro to an uptake of 20.0 ± 4.6 pg MIONs per cell, which was detectable by MRI at minimal density of ~ 3 × 10⁴ cells. Treated limbs indicated cellular distribution throughout the tendon synovial sheath but restricted to the synovial tissues, with no MSCs detected in the tendon or surgical lesion.

The lesion was associated with negligible morbidity with minimal inflammation post surgery. Evaluation of both treated and control lesions showed no evidence of healing of the lesion at 4, 12 and 24 weeks on gross and histological examination.

Conclusions

Unlike other laboratory animal models of tendon injury, this novel model mimics the failed tendon healing seen clinically intra-synovially. Importantly, however, implanted stem cells exhibited homing to synovium niches where they survived for at least 14 days. This phenomenon could be utilised in the development of novel physical or biological approaches to enhance localisation of cells in augmenting intra-synovial tendon repair.

Factors affecting rotator cuff integrity after arthroscopic repair for medium-sized or larger cuff tears: a retrospective cohort study

BACKGROUND

We wished to identify the preoperative prognostic factors associated with structural integrity after repair of medium-sized and larger rotator cuff tears and to determine the cutoff values using receiver operating characteristic curve analysis.

METHODS

The study included 180 patients with medium-sized and larger rotator cuff tears. Each had a minimum 2-year postoperative follow-up by magnetic resonance imaging. We assessed several patient-related and disease-related preoperative factors using univariate and multivariate logistic regression analysis. To determine the cutoff value for the significant variables, receiver operating characteristic curve analysis was performed.

RESULTS

Retears occurred in 28 of the 180 patients (15.6%). Univariate analysis found that retear was significantly affected by the type of work and pattern of tear. The rate of retear was significantly increased in diabetes and with increasing tear size, extent of retraction, delamination, and fatty infiltration. Furthermore, reduced remnant tendon length, distance from the musculotendinous junction to the face of the glenoid, occupation ratio, and acromiohumeral interval were also significant risk factors. In the multivariate analysis, body mass index, diabetes, dyslipidemia, extent of retraction, delamination, distance from musculotendinous junction to face of glenoid, occupation ratio, fatty infiltration of infraspinatus, and acromiohumeral interval remained significant risk factors. The extent of retraction (22.2 mm) and the occupation ratio (53.5%) showed highly accurate cutoff values for predicting retear.

CONCLUSION

Multiple factors influenced the healing process after rotator cuff repair. The best predictors were the extent of retraction and occupation ratio, which could help assist in determining the prognosis after rotator cuff repairs.

Factors Affecting Cost, Outcomes, and Tendon Healing After Arthroscopic Rotator Cuff Repair

BACKGROUND

The purpose of this study was to simultaneously examine costs, functional outcomes, and tendon healing after arthroscopic rotator cuff repair.

METHODS

This was a retrospective, single-surgeon, single-hospital study. Pre- and postoperative Simple Shoulder Test (SST), visual analog scale (VAS) pain, and American Shoulder and Elbow Surgeons (ASES) scores, and postoperative magnetic resonance images (MRIs) were obtained. Direct costs were derived using a unique, validated tool. Costs included overall total direct cost, which included facility use costs, medication costs, supply costs, and other ancillary costs.

RESULTS

85 patients had a minimum 1-year follow-up of functional outcomes (mean of 1.24 years, range 1-3.2 years) and 56 of 85 (66%) had postoperative MRI healing data at an average follow-up of 1.3 years (range 1-3.2 years). Increased direct cost was associated with ASA class III (P < .001) compared with ASA class I, procedures performed at the main operative room (P = .017) compared with those at the surgical center, single-row repair (P < .001) compared with double-row repair, medium and large tear sizes (P < .001 and P = .001) compared with small tear, and increased number of anchors (P ≤ .001 or P < .039 for each additional). Arthroscopic biceps tenodesis was associated with decreased improvement in SST, VAS-pain, and ASES scores (P < .001, .012, and .024), whereas infraspinatus atrophy and large/massive tear size was associated with decreased improvement in ASES scores (P = .03). Obesity (P = .004) and smoking (P = .034) were associated with greater improvement in VAS-pain scores as these were associated with decreased preoperative scores. Seventy percent of tears healed.

CONCLUSIONS

Within our study, factors that increased direct costs were outcome neutral, and factors that improved outcome were cost neutral.

LEVEL OF EVIDENCE

Level IV, retrospective.

The accelerated effect of recombinant human bone morphogenetic protein 2 delivered by β-tricalcium phosphate on tendon-to-bone repair process in rabbit models

BACKGROUND

Bone morphogenetic protein 2 (BMP-2) plays an important role in the tendon-to-bone repair process. However, there is no previous literature on acceleration of the tendon-to-bone repair process by BMP-2 delivered by β-tricalcium phosphate (β-TCP). The aim of this study was to investigate the accelerated effect of recombinant human BMP-2 (rhBMP-2) delivered by β-TCP on the tendon-to-bone repair process.

METHODS

The infraspinatus tendon of elderly female Japanese white rabbits was detached from its insertion site on the humerus. A bone tunnel (4.2 mm) was created at the original insertion site of the tendon, which was repaired using the McLaughlin procedure after filling in β-TCP (porosity 75%) without BMP-2 (control group) or with 10 µg rhBMP-2 (BMP group). The rabbits were sacrificed at the second, fourth, and eighth weeks after surgery for histologic analysis and biomechanical testing. We also evaluated the maturity of the tendon-to-bone junction using the tendon-to-bone maturity score.

RESULTS

Histologic analysis revealed no significant difference between the groups at 2 and 8 weeks but a more abundant organized fibrocartilage at the tendon-to-bone junction in the BMP group at 4 weeks. The tendon-to-bone maturity score improved sequentially. The interface of the BMP group at 4 weeks had significantly improved biomechanical properties than that of the control group.

CONCLUSION

The tendon-to-bone repair process was facilitated by the use of rhBMP-2 delivered by β-TCP at 4 weeks.

Outcomes of rotator cuff augmentation surgery with autologous fascia lata

OBJECTIVE

To evaluate whether augmentation grafts using autologous fascia lata improve functional results for rotator cuff repairs and reduce the retear rate compared to those without augmentation.

MATERIAL AND METHODS

This is a prospective evaluation comprising 20 patients with a complete symptomatic rotator cuff tear. The operations were carried out from a superior approach performing a total cuff repair, for 10 patients we used a suture augmented with an autologous graft taken from their own fascia lata while unaugmented sutures were used for the other 10 patients. The follow-up period lasted for one year post-intervention. We measured variables for tear type, functionality and pain, both baseline and at 6 and 12-month follow ups. We evaluated retear incidence in each group as well as each group's pain and functionality response.

RESULTS

The improved pain levels in the non-graft group evolved gradually over time. Conversely, in the group with the augmentation grafts, average Constant-Murley shoulder outcome scores at six months were already above 10 and were maintained at 12 months. One retear occurred in the graft group and 2 in the group without grafts, thus presenting no significant differences. There were no significant changes in pain and function values at the one year follow up in either group.

CONCLUSION

Our preliminary results regarding rotator cuff augmentation surgery with autologous fascia lata showed a significant improvement in pain levels after 6 months compared to the patients with no augmentation, who required 12 months to reach the same values. After a year of follow up, there were no differences between the mean Constant and pain scores in either intervention group The number of retears in the non-graft group was greater than that in the group with grafts although the difference was not significant.