Rotator Cuff Tissue Research Articles

Arthroscopic Insertion of a Biologic Rotator Cuff Tissue Augmentation After Rotator Cuff Repair

Abstract Tissue augmentation has been used to reinforce repairs of massive chronic rotator cuff tears. This report describes a new technique for arthroscopic insertion of a biologic rotator cuff tissue augmentation. Double-loaded suture anchors are needed for the technique. One suture is used for the rotator cuff repair and 1 suture is used for the tissue augmentation. The sutures for the tissue augmentation are left exiting through accessory portals. Two free sutures are then passed through the repaired rotator cuff, 1 anteromedially and 1 posteromedially via the anterior and posterior cannulae, respectively. One limb from each of these 4 sutures is retrieved through the lateral portal. Each of the 4 limbs exiting through the lateral portal are then passed through the corresponding corner of the tissue augmentation and Mulberry knots are tied in each suture limb, on top of the tissue augmentation. The suture limbs of the 4 sutures exiting through the anterior and posterior cannulae and accessory portals are pulled simultaneously to reduce the tissue augmentation down onto the repaired rotator cuff. A trocar is used to help push the tissue augmentation through the lateral cannula. The Mulberry knots from each of the sutures are sequentially retrieved and tied arthroscopically to secure the tissue augmentation.

Matrix Molecule mRNA Levels in the Bursa and Rotator Cuff of Patients With Full-Thickness Rotator Cuff Tears

The purpose of this study was to evaluate at the mRNA level a subset of extracellular matrix molecules relevant during healing and remodeling of rotator cuff tears. Controlled laboratory study. Bursal and rotator cuff tissue from the margin of the rotator cuff tear were harvested from 10 patients (mean age, 57.5 +/- 7.3 years) undergoing surgical repair of full-thickness rotator cuff tears. There were six male and four female patients with a mean duration of symptoms of 14.6 months (range, 2 to 60 months). The mean tear size was 4.4 cm. In addition, tissue was obtained from 6 cadaveric specimens with no gross evidence of rotator cuff tearing. Reverse transcription polymerase chain reaction (RT-PCR) was performed for type I, II, and III collagen, biglycan, decorin, and aggrecan, and normalized to the housekeeping gene GAPDH. RT-PCR showed that both the bursa and rotator cuff margin had increased mRNA levels for type I and type III collagen in patients with full-thickness rotator cuff tears when compared with normal cadaveric controls. In addition, there was a significant decrease in decorin mRNA levels and an increase in aggrecan mRNA levels in the rotator cuff margin of torn rotator cuff tendons when compared with normal cadaveric controls. These results suggest that both the bursa and rotator cuff margin of patients with rotator cuff tears are actively remodeling after injury and that both tissues may potentially contribute to the healing process following repair. These findings may help clinicians determine what aspects of the repair process can be manipulated to affect optimal ruptured tendon repair.

NONPROSTHETIC MANAGEMENT OF PROXIMAL HUMERAL FRACTURES

Many proximal humeral fractures can be treated without the need for hemiarthroplasty. Treatment choice is affected by fracture location and pattern, as well as by patient factors including age, activity level, quality of bone, and ability to comply with a regimen of therapy. Successful diagnosis and treatment of proximal humeral fractures is dependent on good-quality radiographs, but in some cases, intraoperative assessment of the fracture pattern is required for a complete and accurate diagnosis of the fracture pattern and severity. A discussion of nonsurgical and surgical treatment options and techniques needed to achieve anatomic reduction and stable fixation is important.

Arthroscopic management of massive rotator cuff tears

Massive, retracted tears of the rotator cuff are difficult to manage. They occur more commonly in older individuals with compromised tissues. The retracted, scarred rotator cuff tissues are not easily mobilized and repaired. The tears usually involve more than one tendon and are usually retracted to the level of the glenoid rim. Visualization of a massive tear is a challenge, even when extensile exposures are utilized. Additionally, exposure requires the release of the deltoid origin with associated morbidity and with potential detachment of the repaired deltoid. Once exposed, the torn rotator cuff tissue may not have sufficient length to be adequately mobilized and reduced anatomically. The bone and soft tissues may not be robust enough for repair. Once repaired, the damaged and weakened tissues may not withstand rigorous therapy and can tear once again.

Arthroscopic management of massive rotator cuff tears

Massive, retracted tears of the rotator cuff are difficult to manage. They occur more commonly in older individuals with compromised tissues. The retracted, scarred rotator cuff tissues are not easily mobilized and repaired. The tears usually involve more than one tendon and are usually retracted to the level of the glenoid rim. Visualization of a massive tear is a challenge, even when extensile exposures are utilized. Additionally, exposure requires the release of the deltoid origin with associated morbidity and with potential detachment of the repaired deltoid. Once exposed, the torn rotator cuff tissue may not have sufficient length to be adequately mobilized and reduced anatomically. The bone and soft tissues may not be robust enough for repair. Once repaired, the damaged and weakened tissues may not withstand rigorous therapy and can tear once again.

Apoptosis in rotator cuff tendonopathy

The aim of this study was to investigate the involvement of apoptosis (programmed cell death) in the pathogenesis of rotator cuff disorders. The edges of torn supraspinatus rotator cuff tendons were collected from patients with rotator cuff tear ( n=25). Samples of the intra-articular portion of subscapularis tendons were collected from patients without rotator cuff tear as control ( n=6). To minimize individual variance, we also collected six pairs of supraspinatus tendon and subscapularis tendon from six patients with rotator cuff tears. Apoptosis was detected by in situ DNA end labelling assay and DNA laddering assay. Immunohistochemical staining was performed to identify cells undergoing apoptosis. Control subscapularis tendon had normal morphology. Tendon from torn supraspinatus rotator cuff showed significant mucoid degeneration. Within the areas of degeneration, there were large numbers of apoptotic cells. The percentage of apoptotic cells in the degenerative rotator cuff (34%) was significantly higher than that in controls (13%) ( p<0.001). The excessive apoptosis detected in degenerative rotator cuff tissue was confirmed by DNA laddering assays. This is the first report of excessive apoptosis in degenerating rotator cuff tendon. Cells undergoing apoptosis in rotator cuff were mainly fibroblast-like cells. These finding indicate that apoptosis may play an important role in the pathogenesis of rotator cuff degeneration.

Anterior internal impingement

Purpose: The source of pain in patients with a stable shoulder and clinical signs of impingement is traditionally thought to be subacromial or outlet impingement, as popularized by Neer. This report introduces the concept of anterior internal impingement in patients with signs and symptoms of classic impingement syndrome and arthroscopic evidence of articular-side partial rotator cuff tear. Contact that occurs between the fragmented undersurface of the rotator cuff and the anterosuperior labrum is the apparent source of pain in these patients. Type of Study: Case series. Methods: Ten patients with a primary symptom of pain and an arthroscopic finding of a partial rotator cuff tear were reviewed. Arthroscopic visualization of the subacromial space revealed no evidence of subacromial impingement or bursitis in any patient. All patients had clinical signs and symptoms of classic impingement. The initial part of the surgical procedure consisted of a complete diagnostic arthroscopy in a low-volume gas medium using a single posterior portal. While performing the Hawkins test, the locations of any areas of abnormal soft-tissue contact and impingement were observed directly. Results: There was anterior internal impingement in all 10 patients with partial-thickness rotator cuff tears. The abnormal and fragmented rotator cuff tissue made contact with the anterior superior labrum when the shoulder was visualized from the posterior portal while performing the Hawkins test. Preoperative magnetic resonance imaging correctly showed a partial-thickness rotator cuff tear in 20% of the cases. Conclusions: Recognition of anterior internal impingement as a clinical entity is important because magnetic resonance imaging results are often misleading. This is of particular importance in young patients with isolated lesions in whom arthroscopic acromioplasty and capsular reefing procedures would be unnecessary. When anterior internal impingement is recognized as the source of unresolved shoulder pain, patient selection for surgery and procedure selection can be improved.

Revision rotator cuff repair: factors influencing results.

Revision rotator cuff repair is a surgical challenge, and the results have generally been inferior to those of primary repair. We examined the results of revision rotator cuff repair in a large series of patients and assessed which subgroups of patients had the greatest chance for a satisfactory functional outcome. A revision rotator cuff repair was performed in eighty patients after the failure of a previous operative repair. The average age of the patients at the time of the revision was fifty-nine years. Prior to revision, the average pain score was 7.4 points (with 0 points indicating no pain and 10 points, severe pain) and the active range of motion of the shoulder averaged 105 degrees of elevation, 39 degrees of external rotation, and internal rotation to the eleventh thoracic vertebra. All patients underwent repeat repair of the rotator cuff tendons to bone. Additional procedures included revision acromioplasty (fifty-three patients; 66%) and distal clavicular excision (twenty-six patients; 33%), among others. After an average duration of follow-up of forty-nine months, the result was rated as satisfactory (excellent, good, or fair) in fifty-five patients (69%) and as unsatisfactory (poor) in twenty-five (31%). At the time of the latest follow-up, the average pain score had improved to 3.0 points and the active range of motion averaged 130 degrees of elevation, 53 degrees of external rotation, and internal rotation to the tenth thoracic vertebra. Improved results were associated with an intact deltoid origin, good-quality rotator cuff tissue, preoperative active elevation of the arm above the horizontal, and only one prior procedure. All seventeen patients who met all four of these criteria had a satisfactory result. The results of revision rotator cuff repair are inferior to those of primary repair. While pain relief can be reliably achieved in most patients, the functional results are improved principally in patients with an intact deltoid origin, good-quality rotator cuff tissue, preoperative elevation above the horizontal, and only one prior procedure.

Total shoulder arthroplasty: Factors influencing prosthetic sizing

Prosthetic sizing of the glenohumeral articulation influences postoperative shoulder strength stability and range of motion through its influence on the lateral humeral offset. Prosthetic sizing along with proper prosthetic orientation, soft tissue balancing, capsular release, and rotator cuff repair when necessary, are inter-related factors that significantly influence the function of the prosthetic shoulder. Intraoperative assessment of prosthetic size is determined by the lateral humeral offset rotator cuff tissue tension, intraoperative range of motion, and stability of the shoulder.

Full-Thickness Rotator Cuff Tears: Factors Affecting Surgical Outcome.

Eighty-five percent to 95% of patients who undergo primary surgical repair of full-thickness rotator cuff tears have a significant decrease in shoulder pain and improvement in shoulder function. The results of surgery are dependent on the surgical technique, the extent of pathologic changes in the rotator cuff, and the postoperative rehabilitation protocol. Preoperative factors associated with a less favorable result are the size of the tear, the quality of the tissues, the presence of a chronic rupture of the long head of the biceps tendon, and the degree of preoperative shoulder weakness. Surgical factors associated with a less favorable result include inadequate acromioplasty, residual symptomatic acromioclavicular arthritis, inadequate rotator cuff tissue mobilization, deltoid detachment or denervation, and failure of rotator cuff healing. Clinical evaluation and preoperative imaging of the shoulder will improve patient selection and counseling. Meticulous surgical technique and postoperative rehabilitation will optimize the final result.

Prosthetic replacement in rotator cuff—deficient shoulders

We reviewed a series of 30 shoulders in 25 patients who had glenohumeral arthritis and rotator cuff deficiency and who underwent prosthetic replacement. Nineteen shoulders underwent humeral head replacement, and 11 shoulders had total shoulder arthroplasty. Meticulous mobilization and reconstruction of the deficiencies in the thin atrophic rotator cuff tissues were attempted in all shoulders. Emphasis was placed on anteroposterior stability, and this was achieved in all shoulders; superior coverage was fully achieved in 15 shoulders and was partially achieved in 11. All shoulders had less pain after surgery, and 93% achieved satisfactory pain relief. Total shoulder arthroplasty and humeral hemiarthroplasty were found to provide similar results with respect to pain relief, functional improvement, and patient satisfaction. Shoulders with hemiarthroplasty gained significantly more active elevation (+52° vs + 2°) after surgery. Cuff repair was easier when a humeral head prosthesis alone was used because less lateralization of the humerus occurred. Also, operative time, anesthesia time, and blood loss were decreased with hemiarthroplasty. Because the lack of glenoid resurfacing did not adversely affect pain relief or function and avoided the potential problem of glenoid loosening, we favor humeral hemiarthroplasty as a treatment for glenohumeral arthritis in the rotator cuff-deficient shoulder.

Biomechanical evaluation of rotator cuff fixation methods.

Initial fixation strength and failure mode for various rotator cuff reattachment techniques (variations of the McLaughlin technique) were evaluated. Repair methods included standard suture (control), reinforced suture [expanded polytetrafluoroethylene (PTFE) patch and polydioxanone (PDS) tape augmentation] and stapling (nonarthroscopic and arthroscopic soft-tissue staples). The average strength of intact rotator cuff tissue (supraspinatus tendon) was also determined. The different rotator cuff repairs, including at least one control, were performed on fresh-frozen human cadaver shoulder pairs. Repairs were tested to failure in pure tension with the shoulder fixed in 60 degrees of abduction. Load and displacement data were normalized to controls, grouped according to failure modes, and statistically analyzed. The two basic failure modes observed were 1) bone failure, or suture tearing through the bone (indicating weak bone stock) and 2) tendon failure, or suture tearing of the rotator cuff. Gross comparisons between intact and repaired tendons indicated that the intact tendon was two to three times stronger than the repaired tendon. Based on the mode of failure and lack of increased strength after repair, the use of staples for cuff attachment is discouraged. PDS tape suture reinforcement did not increase fixation strength. In contrast, PTFE patch suture augmentation demonstrated statistically higher initial failure loads than did the control and was of specific benefit for shoulders with weak bone stock.

Surgical Repair of the Rotator Cuff and Surrounding Tissues

The surgical pathology and clinical results of 78 reconstructions of chronic rotator cuff tears were reviewed retrospectively. The predominant complaint preoperatively was chronic pain with impaired shoulder function, resistant to repeated conservative treatment. Results according to a functional assessment were excellent or satisfactory in 71% of the patients, unsatisfactory in 12%, and failed in 17%. Relief of pain including night pain and pain with activity was obtained. Surgery should include a thorough exploration of the rotator cuff and the adjacent tissues. Accompanying problems, including biceps tendon disorders or impingement factors, must be recognized and treated at the time of the reconstruction procedure. Repair of the torn rotator cuff and treatment of concomitant lesions are effective operative procedures when symptoms are persistent and fail to respond to conservative treatment.

Rotator Cuff Tear

Early surgical repair of rotator cuff tears with a partial anterior acromionectomy is recommended as a means of minimizing a progression of symptoms and findings. It was more important to achieve adequate tension in the cuff tissues than to obtain a water-tight closure. Even patients with old complete tears may obtain good results from reconstruction of the rotator cuff. However, merely closing a rotator cuff tear will not permit a good functional result if the ability of the muscles to contract adequately is lost forever. This group of patients rarely achieves full restoration of muscle strength in their operated shoulders, primarily due to muscle atrophy. In shoulders previously operated on, functional results were not as good as in those cases operated on for the first time. Avoidance of interposed soft tissue grafts and restoration of a direct continuity of viable rotator cuff tissue to its bony insertion are recommended whenever possible, to achieve the optimum functional result. In those patients with arthritis of the glenohumeral joint or permanent long-standing nonfunctional rotator cuff muscle, the results of reconstruction were poor. A carefully supervised postoperative rehabilitation program is essential for optimum results.