A Systematic Temporal Assessment of Changes in Tendon Stiffness Following Rotator Cuff Repair.

OBJECTIVES: How the material properties of the human supraspinatus tendon change following arthroscopic rotator cuff repair is undetermined. Shear wave elastography ultrasound is a relatively new, noninvasive measure of tissue stiffness. We aimed to evaluate any temporal changes in stiffness and/or thickness of supraspinatus tendons in humans following primary arthroscopic rotator cuff repair. METHODS: Shear wave elastography was performed at three predetermined regions by a single sonographer at 1-, 6-, 12-, 24-, and 52 weeks postoperatively in 50 consecutive single-row inverted mattress primary arthroscopic rotator cuff repairs. One-way ANOVA with Tukey's correction and Spearman's correlation tests was performed. RESULTS: Of 50 patients, two retore by 1-week and were excluded. Two patients retore at 6 weeks, two at 12 weeks, and one at 24 weeks. The mean tendon stiffness in 48 patients at the tendon footprint increased by 21% (1.32 m/s) at 6 months (P < .001), with the lateral tendon stiffening before the medial tendon. Tendon thickness decreased by 11% (0.6 mm) at 6 weeks (P = .008), then stabilized to 24 weeks. Tendons that were less elastographically stiff at 1 week were more likely to be thinner at 6-weeks (r = .38, P = .010). CONCLUSIONS: The data supports the hypothesis that rotator cuff tendons repaired using the single-row inverted-mattress technique take 6 weeks to heal to bone. Unlike in other tendons, there was no hypertrophic healing response. Prior to 6 weeks, the tendon may stretch/thin-out, particularly if its material properties, as assessed by shear wave elastography, are inferior. The material properties of the tendon improved at the tendon insertion site first, then medially out to 12 months post-repair.

An evaluation of shear wave elastographic characteristics of the supraspinatus tendon after rotator cuff repair.

BACKGROUND: The main complication of rotator cuff repair is retear, which is most common in older patients and patients with greater tear sizes. However, it is unknown why these factors are associated with increased rates of retear. The aim of this study was to determine whether the factors associated with rotator cuff retear (age, tear size, sex, history of trauma, and duration of symptoms) are also associated with decreased mechanical stiffness of the supraspinatus tendon after repair, as assessed by shear wave elastography. METHODS: This was a prospective study of 50 patients undergoing primary rotator cuff repair. A sonographer conducted shear wave elastography ultrasound in all patients at 1, 6, 12, 26, and 52 weeks after repair. The shear wave velocity of the supraspinatus tendon was measured at the tendon-bone interface, 3 mm medial to the interface, and 6 mm medial to the interface. A multiple linear regression analysis was performed with calculation of Cohen F2 values to determine the factors that independently affected supraspinatus tendon stiffness postoperatively. RESULTS: For every decade increase in age, the shear wave velocity of the supraspinatus tendon decreased by 0.5 m/s (P = .004). Greater tear size correlated with reduced supraspinatus shear wave velocity (P < .03 at 6 weeks). Male patients had greater supraspinatus tendon stiffness than female patients (8.2 m/s vs. 6.9 m/s, P = .04). Tendons in patients with a history of trauma were approximately 16% stiffer postoperatively than those in patients with no trauma history (P < .001). Duration of symptoms had no impact on the mechanical stiffness of the supraspinatus tendon. CONCLUSION: Older age, larger tear size, female sex, and nontraumatic tear causation were independently associated with reduced shear wave velocity of the supraspinatus tendon postoperatively. The findings of our study correlate with the results of cohort studies assessing the influence of these variables on rotator cuff retear rates, suggesting that the mechanical stiffness of the supraspinatus tendon, as assessed by shear wave elastography, may have an important association with a successful repair.

Synthetic polytetrafluoroethylene patches for irreparable rotator cuff tears-how are they doing at 5 years?

BACKGROUND: Treating massive and irreparable rotator cuff tears are problematic. Several studies have reported that polytetrafluoroethylene (PTFE) patches demonstrated excellent construct integrity and positive clinical and patient outcomes. However, these studies either had small sample sizes or short follow-up periods. PURPOSE: To determine the survivorship, efficacy, and medium-term (2-19 years) outcomes of PTFE patch repairs. METHODS: This retrospective study used prospectively collected data to establish the medium-term outcomes of PTFE interposition patch repairs for massive rotator cuff tears that could not be repaired by the standard technique. Patients included those who met the ≥2-year follow-up criteria post repair. Standardized assessments of patient-ranked shoulder pain and function and shoulder strength and passive range of motion (ROM) were performed preoperatively and at follow-up visits. Radiographs and ultrasonography were used to evaluate repair integrity, measure proximal humeral head migration, and determine glenohumeral arthritis scores. RESULTS: Forty-one shoulders formed the study cohort at a mean follow-up period of 5 years (range: 2-19 years). The mean age of this group was 72 (standard deviation: 10; range: 50-88) and had 14 cm2 tears at surgery. Twenty-five of 41 (61%) PTFE interposition patch repairs remained intact at an average of 5 years postrepair. Thirteen patches failed at the patch-tendon junction, 1 was removed, and 2 patients underwent reverse total shoulder replacement. Patient-ranked shoulder stiffness (P < .05), frequency of pain during activity and sleep (P < .001), pain levels during overhead activity and rest (P < .001), and overall shoulder function significantly improved from bad preoperatively to fair at the mean 5-year postoperative visit (P < .001). No significant improvements were demonstrated in dynamometer-measured shoulder strength maneuvers and passive ROM. All patients demonstrated proximal humeral head migration on shoulder radiographs regardless of repair integrity (mean Upper Migration Index = 1.2). Failed repairs were associated with higher mean preoperative glenohumeral arthritis grades compared with intact repairs (grade 2 in failed repairs compared with grade 1 in intact repairs) (P < .01). CONCLUSION: PTFE interposition patch repairs for massive and irreparable tears had good construct integrity and clinical outcomes at 2 years. These outcomes were not maintained. PTFE patch repairs often failed at the patch-tendon junction at 4 years and beyond and were ineffective in (1) preventing proximal humeral head migration, (2) stopping progression of glenohumeral arthritis, and (3) improving shoulder strength and ROM.

Fibrillar matrix, Echogenicity, Contour, Thickness, and Suture (FECTS) vs. Global: A comparison of 2 scales developed to assess ultrasound images post rotator cuff repair.

BACKGROUND: Ultrasound is commonly used to assess rotator cuff repair (RCR), but no standardized criterion exists to characterize the tendon. PURPOSE: The aims of this study were to (1) develop content validity for ultrasound specific criteria to grade the postoperative appearance of a tendon after RCR, (2) assess the reliability of the criteria, and (3) assess the feasibility to use these assessments. METHODOLOGY: Following expert consultation and literature review for content validity, 2 scales were created: 1) the Fibrillar matrix, Echogenicity, Contour, Thickness, and Suture (FECTS) scale and 2) the Rotator Cuff Repair-Investigator Global Assessment (RCR-IGA). A prospective cohort study was undertaken on patients who had received a RCR and serial B-mode ultrasound images. Four raters assessed the 64-ultrasound images using the scales created in a blinded fashion using intraclass correlation coefficients. RESULTS: The FECTS scale was a composite score with 5 key parameters and the RCR-IGA scale was a 5-point global score. The intrarater reliability for the FECTS scale was excellent for the most experienced rater (0.92) and fair for the rater with no experience (0.72). The intrarater reliability for the RCR-IGA scale was excellent for 3 of the 4 raters (0.80-0.87) and fair when used by the least experienced rater (0.56). Inter-rater testing for all the FECTS scale parameters had excellent reliability (0.82-0.92) except for Fibrillar matrix (0.73). The average time to complete the FECTS scale per image was 23 seconds and 11 seconds for the RCR-IGA scale. CONCLUSION: The FECTS scale and the RCR-IGA scale are reliable tools to assess the ultrasonic appearance of the repaired rotator cuff tendon. The FECTS scale was more reliable for less experienced assessors. The RCR-IGA scale was easier, more time efficient and reliable for those with experience.

Anteroposterior tear size, age, hospital, and case number are important predictors of repair integrity: an analysis of 1962 consecutive arthroscopic single-row rotator cuff repairs.

BACKGROUND: Retear or nonhealing of a surgically repaired rotator cuff is common, but the determinants of retear are poorly understood. We aimed to determine the relationship between preoperative and intraoperative factors and retear rate following rotator cuff repair and to formulate a predictive model based on this relationship, including any interaction effects between tear size, patient age, and surgical experience in contributing to the retear rate. METHODS: We performed a post hoc analysis of prospectively collected data from 1962 consecutive patients who underwent a primary arthroscopic single-row rotator cuff repair performed by the senior author from 2007 through 2018 and postoperatively returned for 6-month follow-up ultrasonography. RESULTS: Multiple logistic regression analysis revealed anteroposterior tear length to be the most important independent predictor of retear (Wald statistic, 90; P < .001). Other independent predictors included case number (Wald statistic, 59; P < .001), patient age at surgery (Wald statistic, 30; P < .001), and type of hospital (public vs. private) (Wald statistic, 17; P < .001). The data indicated that following rotator cuff repair, there was a 4-fold increase in the retear rate as the anteroposterior tear size increased from 1 cm to 3 cm; a 8-fold decrease when comparing case number 1000 with case number 3000; a 2-fold increase as patient age increased from 50 years to 70 years; and a 3-fold increase when comparing surgery performed in a public hospital vs. a private hospital. The area under the receiver operating characteristic curve was 0.81 (95% confidence interval, 0.78-0.84), indicating that our equation could predict 81% of retears. CONCLUSIONS: Anteroposterior tear length was the most important independent predictor of retear or nonhealing. Other predictive factors included case number, patient age at surgery, and hospital type. The predictive effect of anteroposterior tear length, patient age, and case number in contributing to retear was additive. Our regression equation may be used to calculate patient rotator cuff retear risk at 6 months after repair.

The fate of sutures post rotator cuff repair.

BACKGROUND: Ultrasonographic imaging has been widely used as a diagnostic tool for rotator cuff tears. Several studies have explored the changes in rotator cuff tendon morphology after arthroscopic cuff repair; however, none have addressed the fate of sutures. The aim of this study was to determine (1) if the sutures migrate through the tendon during the postoperative healing period in patients who have had arthroscopic rotator cuff repair; (2) if the sutures do migrate, the time point at which it does; and (3) if the quality of the tendon, in terms of tendon stiffness, modulus of elasticity, bursal thickness, and anatomic footprint, affects suture migration. METHODS: This was a prospective study involving 21 patients who had primary arthroscopic rotator cuff repair performed by a single surgeon. All patients were assessed at 8 days, 6 weeks, 12 weeks, and 24 weeks postrepair; during each assessment, patients underwent an ultrasonographic examination (using a Siemens ACUSON S3000 ultrasonographic system, following a standardized protocol), where supraspinatus tendon thickness and thickness of tendon tissues below and above the suture were measured. Measurements of anatomic footprint, bursal thickness, tendon stiffness, and modulus of elasticity were obtained to assess tendon quality. RESULTS: Of the 21 participants, 14 (67%) had full-thickness tears and 7 (33%) had partial-thickness tears. Between the 12th- and 24th-week follow-up, 2 patients' tendons were found to be not intact. Within the first 12 weeks of the postrepair healing period, the sutures migrated inferiorly, through to the middle of the tendon at the footprint-articular junction (ie, ratio of tendon tissue thickness below the suture to the total tendon thickness = 0.5) (P = .03). The mean anatomic footprint increased from 8.4 ± 1.6 mm to 9.1 ± 1.2 mm between 8 days and 6 weeks (P = .04); bursal thickness decreased during the 24-week period from 1.5 ± 0.9 mm to 0.7 ± 0.4 mm (P = .005); tendon modulus of elasticity increased from 154 ± 75 kPa to 205 ± 96 kPa between 8 days and 24 weeks (P = .05). DISCUSSION: This is the first study to investigate suture position and migration post arthroscopic rotator cuff repair. The findings of this study suggest that sutures migrating to the middle of the tendon during the postoperative healing process is a normal phenomenon observed on ultrasonography.

The Critical Shoulder Angle Shows a Reciprocal Change in Magnitude When Evaluating Symptomatic Full-Thickness Rotator Cuff Tears Versus Primary Glenohumeral Osteoarthritis as Compared With Control Subjects: A Systematic Review and Meta-analysis.

PURPOSE: To determine whether a high critical shoulder angle (CSA) is associated with symptomatic full-thickness rotator cuff (RC) tears and/or whether a low CSA is associated with primary glenohumeral osteoarthritis (GHOA). METHODS: A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All observational studies that examined an association between CSA and full-thickness RC tears and/or primary GHOA were included. A primary meta-analysis was performed including all studies that met the inclusion criteria regardless of radiographic quality. A secondary meta-analysis was performed to explore the hypothesis that radiographic quality was a source of heterogeneity, which excluded those studies in which radiograph quality was not strictly defined and controlled. RESULTS: For the primary meta-analysis, 11 studies met the inclusion criteria for RC tears and 5 for primary GHOA. The CSA was greater in the RC tear group than the control group (mean difference 4.03°, 95% confidence interval 2.95°-5.11, 95% prediction interval 0.0487°-8.01°; P < .001). The CSA was lower in the GHOA group than the control group (mean difference -3.98°, 95% confidence interval -5.66° to -2.31°, 95% prediction interval -10.2° to -2.19°; P < .001).A high level of heterogeneity was observed in the RC tear analysis (I2 = 88.4), which decreased after the exclusion of 5 studies based on radiographic quality (I2 = 75.3). A high level of heterogeneity also was observed in the primary GHOA analysis (I2 = 87.3), which decreased after the exclusion of 2 studies based on the radiographic quality (I2 = 48.2). CONCLUSIONS: There is a reciprocal change in magnitude of the CSA when evaluating symptomatic full-thickness RC tears versus primary GHOA as compared with control subjects. Radiographic quality is a source of heterogeneity in studies that investigate a link between CSA and RC tears and primary GHOA. LEVEL OF EVIDENCE: Level III, systematic review and meta-analysis of Level III studies.

Shoulder stiffness after rotator cuff repair: the fate of stiff shoulders up to 9 years after rotator cuff repair.

BACKGROUND: Stiffness and retear are 2 common complications of rotator cuff repair. McNamara et al found that postoperative stiffness was associated with lower retear rates at 6 months. This study aimed to determine if stiffness after rotator cuff repair protects the individual from retear up to 9 years after surgery. MATERIALS AND METHODS: Two groups of patients, 69 with stiff and 63 with nonstiff shoulder, who underwent arthroscopic rotator cuff repair were created based on external rotation measurements at 6 weeks postoperatively. Patients had regular follow-up assessments at 6, 12, and 24 weeks and were instructed to return for a follow-up at least 2 years after surgery. Patients were assessed for range of motion, shoulder function, strength, and rotator cuff integrity using ultrasound. RESULTS: For patients with postoperative stiffness at 6 weeks, the retear rate at 6 months was 3%, whereas the rate for nonstiff patients was 19% (P = .004). This protective effect of postoperative stiffness persisted up to 9 years after surgery (P = .002). Postoperative stiffness resolved by 5 years after surgery for all measurements except external rotation (50° vs. 61°) (P = .006). Patients with postoperative stiffness had continued improvements in abduction (P < .001), internal rotation (P = .020), and all patient-ranked measurements from the 6-month follow-up to 5 years after surgery. Patients with stiff shoulder had greater overall satisfaction by the final follow-up (P = .028). CONCLUSIONS: In patients experiencing stiffness after rotator cuff surgery, the repair is less likely to fail at 6 months. Although the stiffness generally resolves by 5 years, this protective effect still persists at 9 years after surgery.

Biomechanical comparison of knotless wide suture double-row SutureBridge rotator cuff repair to double-row standard suture repair.

BACKGROUND: A comparison of self-reinforcement and footprint compression between standard- and wide-diameter suture material in double-row SutureBridge repair techniques has not been performed. The aim of this study was to compare the self-reinforcement and footprint contact pressure generated under progressive tensile loads between 2 double-row SutureBridge rotator cuff repair techniques: 1 performed with FiberWire and 1 performed with FiberTape in a knotless technique. MATERIALS AND METHODS: Rotator cuff repairs were performed in 10 pairs of ovine shoulders. One group underwent a double-row SutureBridge repair using FiberWire. The other group underwent an identical repair with FiberTape. Footprint contact pressure was measured from 0° to 60° of abduction under loads of 0-60 N. Pull-to-failure tests were then performed. RESULTS: In both repair constructs at 0° of abduction, each 10-N increase in rotator cuff tensile load led to a significant increase in footprint contact pressure (P < .05). The rate of increase in footprint contact pressure was greater in the FiberTape construct (ratio, 1.68; P = .00035). In both repair constructs, the highest values for footprint contact pressure were seen at 0° of abduction. No difference in pull to failure, peak load, or total energy was found between the groups. CONCLUSION: Self-reinforcement was seen in both double-row SutureBridge repairs with standard- and wide-diameter suture material but was greater in the repair with the wide-diameter suture material construct. Footprint compression is greater in a knotless double-row SutureBridge repair with wide-diameter suture material than in a knotted double-row SutureBridge repair with standard-diameter suture material at 20° of abduction.

Can handheld dynamometry predict rotator cuff tear size? A study in 2100 consecutive patients.

BACKGROUND: This study aimed to determine whether handheld dynamometry measurements could predict rotator cuff tear size in patients who required surgical treatment of their shoulder pathology. METHODS: Handheld dynamometer readings were collected prior to surgery and analyzed retrospectively for 2100 consecutive patients. Post hoc, the cohort was divided into patients with rotator cuff tears (n = 1747) and those without rotator cuff tears (n = 353). The tear group was stratified into partial- vs. full-thickness tears and into 4 groups based on tear size area. RESULTS: Patients with partial-thickness tears had greater internal rotation (P = .03), external rotation (P < .001), and supraspinatus (P < .001) strength than patients with full-thickness tears. Patients with tears had lower supraspinatus strength than patients without tears (r = -0.82, P < .001). Patients with a larger tear size had lower values of external rotation (r = -1.46, P < .001) and supraspinatus (r = -1.18, P < .001) strength. A model involving internal rotation and supraspinatus strength could predict the presence of a tear with a sensitivity of 82% and specificity of 29%. The correct prediction rate was 73% overall (82% in tear group and 29% in no-tear group). The following formula was found to predict rotator cuff tear size, showing modest correlation with our raw data (r = 0.25, P < .001): Tear size = 482.8 + (3.9 × Internal rotation strength) + (1.6 × Adduction strength) - (7.2 × External rotation strength) - (2.0 × Supraspinatus strength). CONCLUSIONS: Handheld dynamometer readings could not reliably predict rotator cuff tear size, showing only modest correlation with our raw data. Handheld dynamometry readings could predict the presence of a tear, although tears in the intact cohort were overestimated (a specificity of 29% and negative predictive value of 25%).

Shoulder abduction diminishes self-reinforcement in transosseous-equivalent rotator cuff repair in both knotted and knotless techniques.

PURPOSE: The self-reinforcement mechanism after double row suturebridge rotator cuff repair generates increasing compressive forces at the tendon footprint with increasing tendon load. Passive range of motion is usually allowed after rotator cuff repair. The mechanism of self-reinforcement could be adversely affected by shoulder abduction. METHODS: Rotator cuff tears were created ex vivo in nine pairs of ovine shoulders. Two different repair techniques were used. One group was repaired using a double row 'suturebridge' construct with tied horizontal medial row mattress sutures (Knotted repair group). The other group was repaired identically except that medial row knots were not tied (Knotless repair group). Footprint compression was measured at varying amounts of abduction and under tendon loads of 0, 10, 20, 30, 40, 50 and 60N. The rate of increase of contact pressure (degree of self-reinforcement) was calculated for each abduction angle. RESULTS: Abduction diminishes footprint contact pressure in both knotted and knotless double row suturebridge constructs. Progressive abduction from 0 to 40 abduction in the knotless group and 0-30 in the knotted group results in a decrease in self-reinforcement. Abduction beyond this does not cause a further decrease in self-reinforcement. There was no difference in the rate of increase of footprint contact pressure at each angle of abduction when comparing the knotted and knotless groups. CONCLUSION: In the post-operative period, high tendon load combined with minimal abduction would be expected to generate the greatest amount of footprint compression which may improve tendon healing. Therefore, to maximize footprint compression the use of abduction pillows should be avoided while early isometric strengthening should be used.

Preventing brachial plexus injury during shoulder surgery: a real-time cadaveric study.

BACKGROUND: Brachial plexopathy is not uncommon after shoulder surgery. Although thought to be due to stretch neuropathy, its etiology is poorly understood. This study aimed to identify arm positions and maneuvers that may risk causing brachial plexopathy during shoulder arthroplasty. METHODS: Tensions in the cords of the brachial plexuses of 6 human cadaveric upper limbs were measured using load cells while each limb was placed in different arm positions and while they underwent shoulder hemiarthroplasty and revision reverse arthroplasty. Arthroplasty procedures in 4 specimens were performed with standard limb positioning (unsupported), and 2 specimens were supported from under the elbow (supported). Each cord then underwent biomechanical testing to identify tension corresponding to 10% strain (the stretch neuropathy threshold in animal models). RESULTS: Tensions exceeding 15 N, 11 N, and 9 N in the lateral, medial, and posterior cords, respectively, produced 10% strain. Shoulder abduction >70° and combined external rotation >60° with extension >50° increased medial cord tension above the 10% strain threshold. Medial cord tensions (mean ± standard error of the mean) in unsupported specimens increased over baseline during hemiarthroplasty (sounder insertion [4.7 ± 0.6 N, P = .04], prosthesis impaction [6.1 ± 0.8 N, P = .04], and arthroplasty reduction [5.0 ± 0.7 N, P = .04]) and revision reverse arthroplasty (retractor positioning [7.2 ± 0.8 N, P = .02]). Supported specimens experienced lower tensions than unsupported specimens. CONCLUSIONS: Shoulder abduction >70°, combined external rotation >60° with extension >50°, and downward forces on the humeral shaft may risk causing brachial plexopathy. Retractor placement, sounder insertion, humeral prosthesis impaction, and arthroplasty reduction increase medial cord tensions during shoulder arthroplasty. Supporting the arm from under the elbow protected the brachial plexus in this cadaveric model.

Knotless double-row SutureBridge rotator cuff repairs have improved self-reinforcement compared with double-row SutureBridge repairs with tied medial knots: a biomechanical study using an ovine model.

BACKGROUND: In double-row SutureBridge (Arthrex, Naples, FL, USA) rotator cuff repairs, increasing tendon load may generate progressively greater compression forces at the repair footprint (self-reinforcement). SutureBridge rotator cuff repairs using tied horizontal mattress sutures medially may limit this effect compared with a knotless construct. MATERIALS AND METHODS: Rotator cuff repairs were performed in 9 pairs of ovine shoulders. One group underwent repair with a double-row SutureBridge construct with tied horizontal medial-row mattress sutures. The other group underwent repair in an identical fashion except that medial-row knots were not tied. Footprint contact pressure was measured at 0° and 20° of abduction under loads of 0 to 60 N. Pull-to-failure tests were then performed. RESULTS: In both repair constructs, each 10-N increase in rotator cuff tensile load led to a significant increase in footprint contact pressure (P < .0001). The rate of increase in footprint contact pressure was greater in the knotless construct (P < .00022; ratio, 1.69). The yield point approached the ultimate load to failure more closely in the knotless model than in the knotted construct (P = .00094). There was no difference in stiffness, ultimate failure load, or total energy to failure between the knotless and knotted techniques. CONCLUSION: In rotator cuff repair with a double-row SutureBridge configuration, self-reinforcement is seen in repairs with and without medial-row knots. Self-reinforcement is greater with the knotless technique.

The effect of rotator cuff repair on early overhead shoulder function: a study in 1600 consecutive rotator cuff repairs.

BACKGROUND: Rotator cuff tears are often surgically repaired, generally with good results. However, repairs not infrequently retear, and how important repair integrity is with respect to early functional outcomes after rotator cuff repair is unclear. Thus, the purpose of this study was to determine the effect of a retear on overhead activities in a large cohort of patients after rotator cuff repair. METHODS: This was a retrospective cohort study of prospectively collected data from 1600 consecutive rotator cuff repairs. Outcomes were based on patient responses to the L'Insalata Shoulder Questionnaire and findings on examination preoperatively and at 6 months of follow-up. Repair integrity was determined by ultrasound imaging at the 6-month follow-up visit. RESULTS: The 1600 patients (885 men, 715 women) were a mean age of 58 years. Postoperative ultrasound imaging found 13% (211 of 1600) of repairs had retorn. Significant improvements were seen irrespective of rotator cuff integrity in pain levels with overhead activity (P < .0001) and range of motion in forward flexion (P < .001) and abduction (P < .01). Patients with intact repairs had 9.5 N greater supraspinatus strength (P < .0001) and 6.9 N greater external rotation strength (P < .01) than those with a retear. CONCLUSION: To our knowledge, this is the largest study to evaluate the effect of rotator cuff repair integrity on shoulder function. Patients who had an arthroscopic rotator cuff repair reported significant improvements in overhead pain levels irrespective of the repair integrity at 6 months. Repair integrity influenced supraspinatus and external rotation power, where patients with intact repairs were stronger than those with a retear.

Short-term outcomes after arthroscopic capsular release for adhesive capsulitis.

BACKGROUND: Little is known about the short-term temporal outcomes of an arthroscopic capsular release for adhesive capsulitis (frozen shoulder). Specifically, it is not known how immediate the improvements are and how quickly patients return to normal function after an arthroscopic release. METHODS: The study included 140 shoulders in 133 patients with idiopathic adhesive capsulitis who underwent a complete arthroscopic release of the shoulder capsule, performed by a single surgeon in a day surgery setting. Patient-reported pain and shoulder function were evaluated with the use of Likert scales, and an independent examiner assessed shoulder strength and range of motion preoperatively and at 1 week, 6 weeks, 12 weeks, and 24 weeks postoperatively. RESULTS: Arthroscopic capsular release resulted in immediate improvements in pain, functional outcomes, and range of motion (P < .0001). External rotation increased from 21° ± 17° (mean ± standard deviation) to 76° ± 17° at 1 week. Passive range of shoulder motion improved at 1 week, deteriorated slightly at 6 weeks, and then continued to improve at 12 and 24 weeks. Before surgery, 38% of patients reported that they "always" experienced extreme pain. This proportion reduced to 30% (P < .0001) at 1 week postoperatively and 2% (P < .0001) at 24 weeks postoperatively. There were no complications. CONCLUSIONS: Patients who underwent an arthroscopic capsular release for idiopathic adhesive capsulitis experienced significant reductions in pain, improvements in range of motion, and improvements in overall shoulder function in the first postoperative week. These immediate improvements in pain and function continue to improve at 6, 12, and 24 weeks postoperatively.

Trauma versus no trauma: an analysis of the effect of tear mechanism on tendon healing in 1300 consecutive patients after arthroscopic rotator cuff repair.

BACKGROUND: Patients with rotator cuff tears often recall a specific initiating event (traumatic), whereas many cannot (nontraumatic). It is unclear how important a history of trauma is to the outcomes of rotator cuff repair. METHODS: This question was addressed in a study cohort of 1300 consecutive patients who completed a preoperative questionnaire regarding their shoulder injury and had a systematic evaluation of shoulder range of motion and strength, a primary arthroscopic rotator cuff repair performed by a single surgeon, an ultrasound scan, and the same subjective and objective measurements made of their shoulder 6 months after surgery. Post hoc, this cohort was separated into 2 groups: those who reported no history of trauma on presentation (n = 489) and those with a history of traumatic injury (n = 811). RESULTS: The retear rate in the group with no history of trauma was 12%, whereas that of the group with a history of trauma was 14% (P = .36). Those patients with a history of shoulder trauma who waited longer than 24 months had higher retear rates (20%) than those who had their surgery earlier (13%) (P = .040). CONCLUSION: Recollection of a traumatic initiating event had little effect on the outcome of arthroscopic rotator cuff repair. Duration of symptoms was important in predicting retears if patients recalled a specific initiating event but not in patients who did not recall any specific initiating event. Patients with a history of trauma should be encouraged to have their rotator cuff tear repaired within 2 years.

The effect of concomitant glenohumeral joint capsule release during rotator cuff repair--a comparative study.

BACKGROUND: There is debate as to whether to operate or to defer surgery on patients with concomitant rotator cuff tear and shoulder stiffness. The purpose of this study was therefore to compare the outcomes in those patients who had both their rotator cuff tear and shoulder stiffness treated with the outcomes of patients who had a rotator cuff repair but no stiffness. METHODS: Twenty-five patients formed the stiffness group (receiving a concomitant rotator cuff repair and manipulation under anesthesia ± arthroscopic capsular release for preoperative ipsilateral stiffness), and a chronologically matched group of 170 rotator cuff repair-only patients formed the nonstiffness group. Patients ranked their pain and function scores preoperatively and at 1 week, 6 weeks, 12 weeks, 6 months, and 2 years postoperatively; examiners recorded range of motion, strength, and presence of impingement signs. Repair integrity was determined using ultrasound. RESULTS: Patients from both groups had significantly improved clinical outcomes at the 2-year follow-up compared with preoperative values. Range of motion was similar between groups at 2 years for forward flexion, abduction, and external rotation, whereas the nonstiffness group had a superior range of internal rotation (P = .014). Stiffness patients had 0 of 25 (0%) retears at 2 years compared with 34 of 170 (20%) in the nonstiffness group (P = .009). CONCLUSIONS: The good outcomes of rotator cuff repair with glenohumeral capsular release disproved our hypothesis and suggest that there is no advantage in delaying repair of a rotator cuff tear to allow stiffness to resolve and that stiffness confers an advantage in terms of repair integrity. LEVEL OF EVIDENCE: Level III; Retrospective Cohort Design; Treatment Study.

The biomechanical effects of polytetrafluoroethylene suture augmentations in lateral-row rotator cuff repairs in an ovine model.

BACKGROUND: This study investigated the biomechanical effects of expanded polytetrafluoroethylene (ePTFE) suture augmentation patches in rotator cuff repair constructs. METHODS: The infraspinatus tendon in 24 cadaveric ovine shoulders was repaired using an inverted horizontal mattress suture with 2 knotless bone anchors (ArthroCare, Austin, TX, USA) in a lateral-row configuration. Four different repair groups (6 per group) were created: (1) standard repair using inverted horizontal mattress sutures, (2) repair with ePTFE suture augmentations on the bursal side of the tendon, (3) repair with ePTFE suture augmentations on the articular side, and, (4) repair with ePTFE suture augmentations on both sides of the tendon. Footprint contact pressure, stiffness, and the load to failure of the repair constructs were measured. RESULTS: Repairs with ePTFE suture augmentations on the bursal side exerted significantly more footprint contact pressure (0.40 ± 0.01 MPa) than those on the articular side (0.34 ± 0.02 MPa, P = .04) and those on both sides (0.33 ± 0.02 MPa, P = .01). At 15 degrees of abduction, ePTFE-augmented repairs on the bursal side had higher footprint contact pressure (0.26 ± 0.03 MPa) compared with standard repairs (0.15 ± 0.02 MPa, P = .01) and with ePTFE-augmented repairs on the articular side (0.18 ± 0.02 MPa, P = .03). The ePTFE-augmented repairs on the bursal side demonstrated significantly higher failure loads (178 ± 18 N) than standard repairs (120 ± 17 N, P = .04). CONCLUSIONS: Inverted horizontal mattress sutures augmented with ePTFE patches on the bursal side of the tendon enhanced footprint contact pressures and the ultimate load to failure of lateral-row rotator cuff repairs in an ovine model.

Man vs. machine: surgeon vs. elastography assessment of the quality of the rotator cuff.

Background: The most common complication of arthroscopic rotator cuff repair is retear, which is more common in larger tears and older patients. We hypothesized that the quality of the torn tendon is important in protecting against retear. Surgeons have traditionally assessed the quality of repaired tendons with a four-point Likert scale. Shear Wave Elastography Ultrasound (SWEUS) is a recent technological advancement that can quantify soft-tissue stiffness. This study aimed to determine how closely a surgeon's intraoperative ranking of tissue quality during rotator cuff repair correlated to postoperative supraspinatus tendon stiffness measured by SWEUS. Methods: This was a prospective case series on 50 patients undergoing arthroscopic rotator cuff repair, involving SWEUS measurements of each patient's supraspinatus tendon at 8 days, 6 weeks, 12 weeks, 6 months, and 12 months. The intraoperative surgeon score of tissue quality for each patient was ranked on a four-point Likert scale. Each patient's scores were compared to postoperative SWEUS velocity measurements of the supraspinatus tendon postrepair. Results: The SWEUS determined stiffness of supraspinatus tendons at their repaired insertion site postrepair increased by 22% from 6.3 ± 0.2 m/s to 7.7 ± 0.3 m/s over 12 months as the tendons healed (P = .0001). Supraspinatus tendon stiffness was greater in patients with smaller tears (r = -0.50, P = .001) and of younger age (r = -0.58, P = .00001). Surgeons also consistently rated younger patients (rs = -0.49, P = .0001) and smaller tears (rs = -0.56, P = .00001) as having superior intraoperative tendon quality. The correlations between SWEUS velocity and surgeon tissue quality rankings were modest at best and strongest at 12 weeks (rs = 0.27, P = .04). There were modest associations between SWEUS tendon stiffness and surgeon tendon mobility rankings at 6 weeks (rs = 0.26, P = .04) and repair quality rankings at 12 months (rs = 0.36, P = .02). Conclusions: These data support the finding that machines (SWEUS) are better at assessing torn rotator cuff tendon quality and whether that tendon will heal after repair than the 'person' performing the surgery. Supraspinatus tendons lose stiffness as they get older and when the tear is larger, likely explaining why retear post-cuff repair is more common with advanced age and larger tears.

Superior and Anterior Glenoid Labral Tears Are Associated With Increased Neurofilament Concentration.

BACKGROUND: Pain is a common presentation after glenohumeral labral injuries. However, the source of that pain is undetermined. PURPOSE/HYPOTHESIS: We aimed to determine if there is a differential expression of nerve fibers around the glenoid labrum and if torn labra have increased neuronal expression compared with untorn labra (rotator cuff repair labra). We hypothesized that the superior labrum would have a higher concentration of neurofilament than would the rest of the labrum and that the concentration of neurofilament would increase at the site of a labral tear. STUDY DESIGN: Descriptive laboratory study. METHODS: Seven labra were sampled at the 3-, 5-, 9-, and 12-o'clock positions during total shoulder arthroplasty. Samples were also collected at the 3-, 5-, and 12-o'clock positions during rotator cuff repair (16 labra), anterior labral repair (6 labra), type II superior labral anterior to posterior (SLAP) repair (4 labra), and capsular release for idiopathic capsulitis (5 labra). Sections were immunostained with antibodies to neurofilament, a specific neuronal marker that is used to identify central and peripheral nerve fibers, and the concentration and intensity of immunostained-positive cells assessed. RESULTS: The concentration of neurofilament staining was similar in the superior, anterior, posterior, and inferior glenoid labrum in untorn labra (8 neurofilament expressing cells per square millimeter; P = .3). Torn labra exhibited a 3- to 4-fold increase in neuronal expression, which was isolated to the location of the tear in SLAP (P = .09) and anterior labral tears (P = .02). The concentration of neurofilament expressing cells in torn glenoid labrum samples was comparable that in with the glenoid labrum of adhesive capsulitis samples (P = .7). CONCLUSION: This study supports the hypothesis that after a tear of the anterior or superior labrum the labrum in that region becomes populated with new nerves fibers and that these fibers may be responsible for the pain noted by patients with superior (SLAP) and/or anterior labral (Bankart) tears. CLINICAL RELEVANCE: This study suggests that neural infiltration contributes to the pain experienced by patients with labral tears. It may help with patient education and direct future management of labral lesions.