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At least 667 records · Page 37Linked to original sources
PubMed2005

Evaluation of denitrification potential of rotating biological contactors for treatment of municipal wastewater.

In this study the effect of retention time and rotation speed in the denitrification process in two full-scale rotating biological contactors (RBC) which were operated parallel and fed with municipal wastewater is evaluated. Each rotating biological contactor was covered to prevent oxygen input. The discs were 40% submerged. On the axle of one of the rotating biological contactors lamellas were placed (RBC1). During the experiments the nitrate removal performance of the rotating biological contactor with lamellas was observed to be less than the other (RBC2) since the lamellas caused oxygen diffusion through their movement. The highest nitrate removal observed was 2.06 g/m2.d achieved by a contact time of 28.84 minutes and a recycle flow of 1 l/s. The rotation speed during this set had the constant value of 0.8 min(-1). Nitrate removal efficiency on RBC1 was decreasing with increasing rotation speed. On the rotating biological contactor without lamellas no effect on denitrification could be determined within a speed range from 0.67 to 2.1 min-1. If operated in proper conditions denitrification on RBC is a very suitable alternative for nitrogen removal that can easily fulfil the nutrient limitations in coastal areas due to the rotating biological contactors economical benefits and uncomplicated handling.

Bioreactors↗
PubMedDate not supplied

Flexible foil exercise and shoulder internal and external rotation strength.

CONTEXT: The efficacy of exercise using a flexible foil to increase strength in the shoulder rotator muscles is unknown. OBJECTIVE: To compare the effects of exercises using a flexible foil (Bodyblade) with exercises using elastic bands on shoulder internal and external rotator muscle strength. DESIGN: We used a randomized, controlled pretest-posttest design. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Forty young adults with no previous shoulder injury. INTERVENTION(S): Experimental subjects participated in an 8-week program of internal and external rotation exercises consisting of 3 sessions per week. MAIN OUTCOME MEASURE(S): Strength was tested by internal and external rotation isometric and isokinetic strength tests at 60 degrees .s (-1) and 120 degrees .s (-1). RESULTS: The group exercising with elastic bands had a greater pretest-posttest increase in maximal internal rotation isometric torque at 10 degrees of internal rotation and greater maximal external rotation isometric torque at 65 degrees of external rotation than the control group. The group using a flexible foil did not show an increase in strength significantly different from either the control or elastic band groups. We found no other statistically significant differences. CONCLUSIONS: Our results do not support the use of a flexible foil for strength gains in shoulder internal and external rotation in the asymptomatic young adult population.

Journal Article↗
PubMed1997

Diagnosis of tears in rotator-cuff-injuries.

Pathology of the rotator cuff is the cause of most common problems at the shoulder joint. Acute injuries are not as frequent as chronic cuff disease, but often they aggravate inflammatory or degenerative tendon alterations, even if they are of minor severity. Traumatic rotator cuff tears predominantly affect the supraspinatus tendon or the rotator interval. The subscapularis tendon is involved in anterior dislocations of the glenohumeral joint or in direct trauma. Plain film radiography still remains the base of all further imaging studies. If only full-thickness tears must be ruled out, double-contrast arthrography and ultrasound are acceptable imaging modalities. However, the former has a drawback in being invasive and does not detect partial tears at the bursal site of the cuff or rotator cuff tendinopathy, whereas the latter heavily depends on the experience of the radiologist and is restricted to the rotator cuff. Nowadays the most comprehensive imaging method is magnetic resonance (MR) imaging. MR imaging enables the detection or exclusion of complete rotator cuff tears with a reasonable accuracy and is also suitable to diagnose further pathologies of the shoulder joint. MR arthrography is valuable in the detection of subtle anatomic details and further improves the differentiation of rotator cuff diseases. Although in comparison MR imaging is still the most expensive imaging method, its high negative predictive value for the diagnosis of complete rotator cuff tears and its reliability evaluating different shoulder joint pathologies make it the preferred imaging modality.

Humans↗
PubMedDate not supplied

Latissimus dorsi and teres major transfer to rotator cuff for Erb's palsy.

During a 20-year period the authors operated on 56 patients with Erb's palsy to create active external rotation of the shoulder. Thirty-five patients had a follow-up period longer than 2 years (average 5 years), which allowed comparison with preoperative motion and strength. Preoperative passive external rotation averaged 5 degrees, whereas active abduction averaged 74 degrees. Preoperative external rotation strength was less than grade 2, whereas preoperative abduction strength was grade 2 or 3 in 33 of the 35 patients. Postoperative active external rotation averaged 31 degrees with only two recurrent internal rotation contractures. Postoperative active abduction averaged 120 degrees. Postoperative strength in external rotation increased in 29 of the 35 patients, with abduction strength increasing one or more grades in 13 of the 35 patients. Four complications occurred. Three patients continued to lose external rotation and required further surgical procedures, and a fourth had a superficial infection. This procedure compares well with the classic transfers to the proximal humerus in that it provides active external rotation in most cases and in some increases shoulder abduction strength.

Adolescent↗
PubMedDate not supplied

[Stress on the rotator cuff sutures in relation to joint position].

UNLABELLED: In a vitro study we evaluated the influence of surgical technique on the postoperative tension of the supraspinatus tendon in rotator cuff ruptures. In ten shoulder specimens Hall-Effect Strain Gauge (HEST) were implanted in the supraspinatus tendon close to the insertion at the humerus. We documented the tension in specimens with intact rotator cuff as well as after reconstruction of small and large tears in different joint positions. In the specimens with an intact rotator cuff there was almost no tension registered. Only in adduction with external rotation and flexion we found slightly increased values. After reconstruction we found the highest tension in adduction, flexion, and external rotation of the humerus. Release of the coracohumeral ligament resulted in a decrease of tension in flexion and external rotation. Whereas in extension coracohumeral ligament release had no influence on the tension of the tendon. However, after complete capsule release the tension in extension also decreased. CLINICAL RELEVANCE: If mobilisation in cases of rotator cuff reconstruction is necessary we recommend first release of the coracohumeral ligament in small and moderate tears. In major tears a complete capsule release is necessary. During physical therapy in the early postoperative course, flexion in the adducted and externally rotated arm should be avoided.

Adult↗
PubMed1998

Quantitative assessment of the muscles of the rotator cuff with magnetic resonance imaging.

RATIONALE AND OBJECTIVES: The purpose of this study was to establish a magnetic resonance (MR) imaging standard for quantification of the muscles of the rotator cuff. METHODS: Parasagittal T1-weighted turbo spin-echo images of the shoulder were obtained in 70 asymptomatic subjects (35 women, 35 men; age range: 21-70 years, mean: 45 years). Standardized cross-sectional areas (rotator cuff muscle areas divided by the area of the supraspinatus fossa) and standardized signal intensities (related to signal intensities of the teres major muscle) were measured and compared with 30 patients with different stages of rotator cuff tears and 10 patients with glenohumeral instability. In addition, a so-called tangent sign was evaluated with the hypothesis that a healthy supraspinatus muscle crosses a line (tangent) drawn through the superior borders of the scapular spine and the superior margin of the coracoid. RESULTS: Cross-sectional areas of the muscles of the rotator cuff were variable in asymptomatic subjects. Cross-sectional areas (but not signal intensities) did discriminate patients with different stages of rotator cuff tears from asymptomatic subjects. The tangent sign was negative in all asymptomatic subjects but positive in four and nine of 10 patients with medium and large rotator cuff tears, respectively. CONCLUSIONS: A method for quantification of the muscles of the rotator cuff using MR imaging is presented. Cross-sectional areas can be used for quantification of the muscles of the rotator cuff. The tangent sign is a useful MR sign for atrophy of the supraspinatus muscle.

Adult↗
PubMed2006

US appearance of the rotator cable with histologic correlation: preliminary results.

PURPOSE: To characterize the ultrasonographic (US) appearance of the rotator cuff cable in asymptomatic shoulders and in cadaveric specimens, with histologic comparison for the latter. MATERIALS AND METHODS: The cadaveric portion of this study was approved by the institution's Anatomical Donations Department. Institutional review board approval and informed consent were obtained from asymptomatic volunteers and clinical patients for the HIPAA-compliant portion of the study. Four fresh cadaveric shoulder specimens (two male subjects, 40 and 50 years old) were dissected, assessed for the presence of the rotator cable, and imaged with 12-MHz US. Histologic slides (hematoxylin-eosin stain) from three resected rotator cuff tendons were inspected for fibers in the expected location and orientation of the rotator cuff cable. The shoulders in 17 asymptomatic volunteers (seven men, two women; age range, 27-66 years; mean, 41 years) and contralateral asymptomatic shoulders in 10 patients (six men, four women; age range, 24-78 years; mean, 49 years) were scanned and evaluated for the presence and appearance of the rotator cable. RESULTS: The rotator cable was identified at gross dissection. Histologic examination and US of the cadaveric shoulders demonstrated an articular-sided fibrillar structure perpendicular to the rotator cuff tendon (average thickness and width, 1.2 mm and 4.5 mm, respectively). US of asymptomatic shoulders depicted a similar fibrillar structure in three (11%) shoulders up to 1.1-1.5 cm medial to the greater tuberosity (average thickness and width, 1.2 mm and 4.5 mm respectively). CONCLUSION: The rotator cable can be depicted with US.

Adult↗
PubMedDate not supplied

From the RSNA refresher courses: US of the rotator cuff: pitfalls, limitations, and artifacts.

High-resolution ultrasonography (US) has gained increasing popularity as a diagnostic tool for assessment of the soft tissues in shoulder impingement syndrome. US is a powerful and accurate method for diagnosis of rotator cuff tears and other rotator cuff abnormalities, provided the examiner has a detailed knowledge of shoulder anatomy, uses a standardized examination technique, and has a thorough understanding of the potential pitfalls, limitations, and artifacts. False-positive sonographic findings of rotator cuff tears can be caused by the technique (anisotropy, transducer positioning, acoustic shadowing by the deltoid septum), by the anatomy (rotator cuff interval, supraspinatus-infraspinatus interface, musculotendinous junction, fibrocartilaginous insertion), or by disease (criteria for diagnosis of rotator cuff tears, tendon inhomogeneity, acoustic shadowing by scar tissue or calcification, rotator cuff thinning). False-negative sonographic findings of rotator cuff tears can be caused by the technique (transducer frequency, suboptimal focusing, imaging protocol, transducer handling), by the anatomy (nondiastasis of the ruptured tendon fibers, posttraumatic obscuration of landmarks), by disease (tendinosis, calcifications, synovial proliferation, granulation or scar tissue, bursal thickening, massive rotator cuff tears), or by patient factors (obesity, muscularity, limited shoulder motion).

Diagnosis, Differential↗
PubMed2005

Tendon-to-bone pressure distributions at a repaired rotator cuff footprint using transosseous suture and suture anchor fixation techniques.

BACKGROUND: Interface contact pressure between the tendon and bone has been shown to influence healing. This study evaluates the interface pressure of the rotator cuff tendon to the greater tuberosity for different rotator cuff repair techniques. HYPOTHESIS: The transosseous tunnel rotator cuff repair technique provides larger pressure distributions over a defined insertion footprint than do suture anchor techniques. STUDY DESIGN: Controlled laboratory study. METHODS: Simulated rotator cuff tears over a 1 x 2-cm infraspinatus insertion footprint were created in 25 bovine shoulders. A transosseous tunnel simple suture technique (n = 8), suture anchor simple technique (n = 9), and suture anchor mattress technique (n = 8) were used for repair. Pressurized contact areas and mean pressures of the repaired tendon against the tuberosity were determined using pressure-sensitive film placed between the tendon and the tuberosity. RESULTS: The mean contact area between the tendon and tuberosity insertion footprint was significantly greater for the transosseous technique (67.7 +/- 5.8 mm(2)) compared with the suture anchor simple (34.1 +/- 9.4 mm(2)) and suture anchor mattress (26.0 +/- 5.3 mm(2)) techniques (P < .05). The mean interface pressure exerted over the footprint by the tendon was also greater for the transosseous technique (0.32 +/- 0.05 MPa) compared with the suture anchor simple (0.26 +/- 0.04 MPa) and suture anchor mattress (0.24 +/- 0.02 MPa) techniques (P < .05). CONCLUSION: The transosseous tunnel rotator cuff repair technique creates significantly more contact and greater overall pressure distribution over a defined footprint when compared with suture anchor techniques. CLINICAL RELEVANCE: Stronger and faster rotator cuff healing may be expected when beneficial pressure distributions exist between the repaired rotator cuff and its insertion footprint. Tendon-to-tuberosity pressure and contact characteristics should be considered in the development of improved open and arthroscopic rotator cuff repair techniques.

Animals↗
PubMed2005

Tendon-bone interface motion in transosseous suture and suture anchor rotator cuff repair techniques.

BACKGROUND: Although many studies involving rotator cuff repair fixation have focused on ultimate fixation strength and ability to restore the tendon's native footprint, no studies have characterized the stability of the repair with regard to motion between the tendon and repair site footprint. HYPOTHESIS: Suture anchor fixation for rotator cuff repair has greater interface motion between tendon and bone than does transosseous suture fixation. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve fresh-frozen human cadaveric shoulders were tested in a custom device to position the shoulder in internal and external rotations with simulated supraspinatus muscle loading. Tendon motion relative to the insertional footprint on the greater tuberosity was determined optically using a digital camera rigidly connected to the humerus, with the humerus positioned at 60 degrees of internal rotation and 60 degrees of external rotation. Testing was performed for the intact tendon, a complete supraspinatus tear, a suture anchor repair, and a transosseous tunnel repair. RESULTS: Difference in tendon-bone interface motion when compared with the intact tendon was 7.14 +/- 3.72 mm for the torn rotator cuff condition, 2.35 +/- 1.26 mm for the suture anchor repair, and 0.02 +/- 1.18 mm for the transosseous suture repair. The transosseous suture repair demonstrated significantly less motion when compared with the torn rotator cuff and suture anchor repair conditions (P < .05). CONCLUSION: Transosseous suture repair compared with suture anchor repair demonstrated superior tendon fixation with reduced motion at the tendon-to-tuberosity interface. CLINICAL RELEVANCE: Development of new fixation techniques for arthroscopic and open rotator cuff repairs should attempt to minimize interface motion of the tendon relative to the tuberosity.

Arthroscopy↗
PubMed2005

Repair of full-thickness rotator cuff tears in professional baseball players.

BACKGROUND: Despite the relative frequency of partial-thickness rotator cuff tears seen in baseball players, full-thickness rotator cuff tears in baseball players are uncommon. HYPOTHESIS: Return to competitive baseball is difficult after surgical treatment of a full-thickness rotator cuff tear. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We evaluated the results of 16 professional baseball players after a mini-open repair of a full-thickness rotator cuff tear. Twelve patients were pitchers with injury to their dominant shoulders. Four patients were position players; 2 had injuries involving their dominant shoulders, and 2 had injuries to their nondominant shoulders. RESULTS: At a mean follow-up of 66.6 months for the pitchers, only 1 player (8%) was able to return to a high competitive level of baseball with no significant shoulder dysfunction after mini-open repair of a full-thickness rotator cuff tear. Of the 2 position players with mini-open repairs of the full-thickness rotator cuff tear of their dominant shoulders, 1 was able to return to professional baseball. Of the 2 position players with mini-open repairs of the full-thickness rotator cuff tear of their nondominant shoulders, both were able to return to professional baseball at the same or higher level. CONCLUSION: It is very difficult for a professional baseball pitcher to return to a competitive level of pitching after a full-thickness rotator cuff repair with a mini-open approach.

Adult↗
PubMed2006

Rotator cuff contusions of the shoulder in professional football players: epidemiology and magnetic resonance imaging findings.

BACKGROUND: No published reports have studied the epidemiology and magnetic resonance imaging findings associated with rotator cuff contusions of the shoulder in professional football players. PURPOSE: To determine a single professional football team's incidence, treatment, and magnetic resonance imaging appearance of players sustaining rotator cuff contusions of the shoulder. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From 1999 to 2005, a North American professional football team's injury records were retrospectively reviewed for athletes who had sustained a rotator cuff contusion of the shoulder during in-season participation. Those patients who had magnetic resonance imaging of the shoulder with a 1.5-Tesla magnet were reviewed by a musculoskeletal radiologist and graded according to the appearance and severity of clinical injury. RESULTS: Twenty-six players had a rotator cuff contusion. There was an average of 5.5 rotator cuff contusions per season (47% of all shoulder injuries). The predominant mechanism of injury was a direct blow in 70.3%. Magnetic resonance imaging findings included peritendon edema at the myotendinous junction, critical zone tendon edema, and subentheseal bone bruises. Treatment consisted of a protocol involving modalities and cuff rehabilitation in all patients. Six patients had persistent pain and weakness for a minimum of 3 days and were given a subacromial corticosteroid injection. Overall, 3 patients (11.4%) required later surgical treatment on the shoulder. CONCLUSION: Rotator cuff contusions accounted for nearly half of all shoulder injuries in the football players in this study. Magnetic resonance imaging is an extremely useful tool in determining severity of injury and integrity of the rotator cuff. The majority of athletes are able to return to sports with conservative treatment; a minority of shoulders might progress to more severe injuries such as rotator cuff tears.

Adult↗
PubMed2005

Surgically repaired massive rotator cuff tears: MRI of tendon integrity, muscle fatty degeneration, and muscle atrophy correlated with intraoperative and clinical findings.

OBJECTIVE: Our goal in this study was to evaluate by means of MRI the clinical significance of tendon integrity, muscle fatty degeneration, and muscle atrophy in surgically repaired massive rotator cuff tears and to correlate these and other prognostic factors with intraoperative and clinical findings. MATERIALS AND METHODS: Twenty-eight surgically proven massive rotator cuff tears were retrospectively included in the study. Twenty-two patients underwent complete repair, and six patients underwent partial repair. Preoperative and postoperative clinical assessment was performed by using the University of California at Los Angeles score. Preoperative and postoperative MRI studies were evaluated for the presence and extent of rotator cuff tear and for the degree of fatty degeneration and atrophy of the rotator cuff muscles. RESULTS: At a mean 44.4 months' follow-up, 20 patients (71.4%) had a favorable result. A total of 25 patients (89.2%) showed postoperative full-thickness rotator cuff tear, 19 of which were reruptures. A sagittal preoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 100% for predicting a favorable outcome. A coronal postoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 85.7% and a positive predictive value of 92.9% for predicting a favorable outcome. A postoperative fatty degeneration of infraspinatus muscle less than or equal to 2 had a specificity of 87.5% and a positive predictive value of 90.9% for predicting a favorable outcome. CONCLUSION: Open repair of massive rotator cuff tears may reach a favorable outcome in a significant proportion of patients, despite a high rate of recurrent or residual tears. Oblique coronal sizes of the recurrent or residual tear of less than or equal to 34 mm and postoperative fatty degenerations of infraspinatus muscle of less than or equal to 2 may allow a favorable outcome.

Adipose Tissue↗
PubMedDate not supplied

Chronic massive rotator cuff tears: evaluation and management.

Most studies of rotator cuff repairs report high success rates. However, the majority of these studies combine the results of surgical management of rotator cuff tears of various sizes; few published reports specifically evaluate the management of chronic massive tears. Chronic massive rotator cuff tears may be acute traumatic, chronic atraumatic, or acute-on-chronic. A detailed history and thorough physical examination often are sufficient to establish the diagnosis. Radiographic evaluation can reveal osseous changes suggestive of pathology. Magnetic resonance imaging can determine the size of rotator cuff tears and status of the muscles but generally is not necessary for patients who are not candidates for surgery. Chronic massive rotator cuff tears without glenohumeral arthritis can be managed nonsurgically or with sub-acromial debridement, rotator cuff repair, or rotator cuff reconstruction. However, treatment of these patients is challenging, and results are comparatively inferior to those of treating patients with smaller rotator cuff tears.

Acromion↗
PubMed1999

[Arthroplasty with a mobile cup for shoulder arthrosis with irreparable rotator cuff rupture: preliminary results and cineradiographic study].

PURPOSE OF THE STUDY: Management of patients with massive irreparable rotator cuff tears associated with severe glenohumeral joint degeneration presents a difficult clinical challenge. The present study reports on 24 patients with disabling shoulder pain due to rotator cuff arthropathy treated using a bipolar arthroplasty. MATERIAL AND METHODS: Between 1995 and 1997, a bipolar shoulder arthroplasty (Biomet, Warsaw, In) was used in 24 patients (25 shoulders) with rotator cuff arthropathy. Patients were monitored for an average of 14.5 months (range 12 to 24 months). The coracoacromial ligament was maintained in all patients to provide anterosuperior stability. The rotator cuff was irreparable and no attempt was made to cover the superior defect. Postoperative results were reviewed with the Constant score and the Swanson score. In order to verify the head-shell motion and to analyze the dynamic comportement of bipolar arthroplasties, we recorded anterior active elevation and active rotations with video-fluoroscopy. RESULTS: At final the follow-up, 21 shoulders had no or slight pain. Average active flexion improved to 84.8 degrees after operation from 62.4 degrees beforehand. 13 patients achieved more than 90 degrees of active flexion after operation. Active external rotation improved from a mean 3 to 28.8 degrees. Before surgery the average Constant score was 17.62. Postoperatively, the average Constant score was 46.97 and the average Swanson score was 23.13. Complications requiring reoperation occurred in 2 cases: 1 component dislocation (Head-shell), 1 subluxation of the long head of the biceps. Radiographic evaluation at follow up demonstrated no humeral stem loosening or component migration and no bony erosion of the coracoacromial arch. Rupture of the infraspinatus tendon (absolute Constant score: p = 0.04, adjusted Constant score: p = 0.02, Swanson score: p = 0.03, Functional score: p = 0.04), preoperative anterior subluxation of the humeral head (absolute Constant score: p = 0.03, adjusted Constant score: p = 0.05, anterior elevation: p = 0.01, functional score: p = 0.04), preoperative narrowing of the acromio-humeral interval (adjusted Constant score: p = 0.02, overall mobility: p = 0.02, anterior elevation: p = 0.03) may jeopardize the subsequent success of bipolar shoulder arthroplasty. The results of this study suggest that the radius curvature of the shell must match that of the bony surface of the glenoid and the coracoacromial arch (absolute Constant score: p = 0.003, adjusted Constant score: p = 0.005, overall mobility: p = 0.002, anterior elevation: p = 0.0008, functional score: p = 0.002). Recording of anterior active elevation with video-fluoroscopy allowed to identify 3 different types of movements after bipolar shoulder arthroplasty. Recording of internal and external rotation allowed to distinguish 2 differents types of movements. Motion appeared to occur between the bipolar shell and the head. The amount of motion was variable and depended on the biomechanics. DISCUSSION AND CONCLUSION: Bipolar shoulder arthroplasty is an effective surgical option for patients with massive irreparable tears of the rotator cuff with concomitant glenohumeral arthritis. Satisfactory pain relief and modest gains in motion result in significant functional improvement in this "low functional demand" population. Predictive factors have been identified and should be discussed before surgery.

Activities of Daily Living↗
PubMed1998

The treatment of failed rotator cuff repairs.

Results following surgical management of failed rotator cuff tears are clearly inferior to those obtained in the treatment of primary repairs. Conservative management may be the treatment of choice in selected patients with failed rotator cuff repairs. The primary goal for revision rotator cuff surgery should be relief of pain, not improvement in function. If the level of pain is manageable, and the patient is functioning with respect to activities of daily living, additional surgery may not be helpful. As there are multiple etiologies associated with failure of the initial repair, each patient should be carefully evaluated on an individual basis to determine if a subsequent procedure would be appropriate. Repeat repair is more likely to succeed in patients with an intact and functioning deltoid, an intact lateral portion of the acromion, and good quality of rotator cuff tissue. Conversely, patients who have had a lateral or radical acromionectomy, a detached or nonfunctioning deltoid, or poor quality of remaining rotator cuff tissue are less likely to have a successful result after repeat repair. It is evident that some of the factors associated with failure are avoidable. As the best chance for a successful result is at the time of the primary repair, the following points will briefly review these factors. The skin incision should be made in the flexion creases which are perpendicular to the deltoid fibers. The deltoid origin should be meticulously protected during the repair and lateral or radical acromionectomy should not be performed. Adequate anterior acromioplasty is essential for removal of the impingement lesion and to prevent subsequent wear on the repaired cuff tendon. The acromioclavicular joint should be evaluated preoperatively and treated as indicated at the time of the surgery. Adequate release of adhesions and mobilization of rotator cuff tissue should be performed using the coracohumeral ligament release and interval slide when necessary. The rotator cuff should be repaired to bone using tendon to bone sutures and/or secure suture anchors. In large and massive tears, there appears to be a role for the reattachment of the coracohumeral ligament. Early phase I range of motion should be initiated following rotator cuff repair and early resistance exercise with weights should be avoided.

Adult↗
PubMed2026

The impact of an intact rotator cuff on the outcomes of reverse shoulder arthroplasty: a meta-analysis of 20,924 patients.

BACKGROUND: While reverse shoulder arthroplasty (rTSA) is commonly utilized for rotator cuff tear arthropathy, indications have expanded to include, primary glenohumeral osteoarthritis (GHOA) with intact cuff. The presence of an intact cuff may influence outcomes after rTSA because preserved cuff musculature can contribute to shoulder stability and force which could potentially improve postoperative function and reduce complication rates. However, studies have reported contradictory results on whether or not an intact cuff would provide better outcomes in patients receiving an rTSA. METHODS: This is a systematic review and Meta-analysis performed according the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Cochrane, Embase, and Google Scholar (pages 1-20) were queried through December 2025. Inclusion criteria consisted of studies comparing the outcomes of rTSA based on whether patients had a diagnosis of GHOA with intact cuff, or had a deficient rotator cuff (ie had a diagnosis of rotator cuff tears without OA, or cuff tear arthropathy). Extracted data included adverse events, improvement in patient reported outcome measures, and improvement in range of motion. RESULTS: Eleven retrospective articles and 1 prospective article met the inclusion criteria with 4,542 in the GHOA with intact cuff group and 16,382 in the cuff-deficient group (cuff tear arthropathy: 15,423 patients; rotator cuff tear: 959 patients). Patients undergoing rTSA for GHOA and intact cuff had a lower rate of revisions (odds ratio [OR] = 0.53; 95% CI: 0.41- 0.68, P < .001; I2 = 0%), overall complications (OR = 0.57; 95% CI: 0.46-0.71, P < .001; I2 = 0%), acromial stress fracture (OR = 0.22; 95% CI: 0.08- 0.59, P = .003; I2 = 0%), infection (OR = 0.43; 95% CI: 0.26- 0.73, P = .002; I2 = 37%), and instability (OR = 0.60; 95% CI: 0.40- 0.90, P = .01; I2 = 0%). In addition, GHOA patients had a better improvement in both American Shoulder and Elbow Surgeons scores (mean difference = 7.17; 95% CI: 2.13- 12.21, P = .005; I2 = 81%) without exceeding the minimal clinically important difference, and external rotation (mean difference = 12.00&#xb0;; 95% CI: 9.63- 14.37, P < .001; I2 = 38%). CONCLUSION: Rotator cuff-deficient patients undergoing rTSA have a higher risk of postoperative complications compared to patients undergoing rTSA for GHOA with an intact cuff. They also showed less improvement in American Shoulder and Elbow Surgeons scores and external rotation. However, the clinical significance of these differences should be interpreted with caution, as not all improvements exceeded established thresholds for clinical importance.

Humans↗
PubMed1998

Right-left asymmetry of cell proliferation predominates in mouse embryos undergoing clockwise axial rotation.

BACKGROUND: Differential growth is fundamental to most mechanisms proposed for axial rotation in amniotes. Other mechanisms such as changes in cell shape are not consistently suggested by ultrastructure. Lateral asymmetries in cell proliferation exist in mouse and chick embryos undergoing normal, anticlockwise axial rotation, but there has been no investigation of inverse clockwise rotation that could test the correlation. METHODS: We used the BALB/cHu-iv/iv, situs inversus mouse to test the apparent correlation of lateral asymmetries with morphogenesis that we saw in cell division patterns of normally rotating mice. Proliferation indices were collected from tritium autoradiograms. RESULTS: Asymmetry of cell proliferation in inverse axial rotation is a mirror image of the pattern seen for normal axial rotation: right predominates over left. This asymmetry is statistically significant and correlates with morphology. Patterns of proliferation in constraining extraembryonic membranes, particularly visceral yolk sac, suggest that rotation could be pushed by uneven lateral growth as body and gut tubes form, for they are attached to these membranes. CONCLUSIONS: Data from iv/iv mice provide additional evidence that differential growth, constrained by contiguous extraembryonic membranes, may drive closure of body and gut walls and contribute to axial rotation. Asymmetries of cell proliferation are likely consequences of genetic cascades, and will need to be incorporated with in situ information on gene activity.

Animals↗