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American Journal of Sports Medicine | 2010

Retear Patterns After Arthroscopic Rotator Cuff Repair Single-Row Versus Suture Bridge Technique

Nam Su Cho; Jin Woong Yi; Bong Gun Lee; Yong Girl Rhee

Background A subset of patients is often seen with an unusual pattern of tendon failure after arthroscopic rotator cuff repair using a suture bridge technique. Purpose To evaluate retear patterns in cases with structural failure after arthroscopic primary repairs of rotator cuff tears. Study Design Cohort study; Level of evidence, 3. Methods Forty-six cases revealing retear on magnetic resonance imaging performed at least 6 months after arthroscopic repair for the treatment of full-thickness rotator cuff tear were evaluated. A single-row technique had been performed in 19 cases and a suture bridge in 27 cases. According to retear patterns on postoperative magnetic resonance imaging, cases were divided into type 1 (cuff tissue repaired at the insertion site of rotator cuff was not observed remaining on the greater tuberosity) and type 2 (remnant cuff tissue remained at the insertion site in spite of retear). Results In the single-row group, 14 cases (73.7%) had type 1 and 5 cases (26.3%) type 2 retear. In the suture bridge group, 7 cases (25.9%) had type 1 and 20 cases (74.1%) type 2. There were statistically significant differences between groups (P = .049). Extent of fatty degeneration of the rotator cuff did not affect retear patterns in the single-row group (P = .160). In the suture bridge group, the percentage of type 1 retear increased with severity of fatty degeneration (P = .030). Extent of muscle atrophy did not affect retear patterns of the single-row group; in the suture bridge group, the percentage of type 1 retear increased with severity of muscle atrophy (P = .904 vs .029). Conclusion The suture bridge technique tended to better preserve the cuff tissue repaired to the insertion site of the rotator cuff than a single-row technique did; the retear in cases with a suture bridge technique was mainly in the musculotendinous junction. Direct retear at the footprint of the rotator cuff increased with severity of fatty degeneration or muscle atrophy in cases with a suture bridge technique.


American Journal of Sports Medicine | 2006

Anterior Shoulder Stabilization in Collision Athletes Arthroscopic Versus Open Bankart Repair

Yong Girl Rhee; Jeong Han Ha; Nam Su Cho

Background Collision athletes are reported to be at high risk for redislocation after anterior stabilization of shoulder instability. Some authors have suggested that arthroscopic stabilization produces results similar to those of open stabilization. Purpose To evaluate the results of anterior shoulder stabilization in collision athletes and to compare the clinical results between the arthroscopic and open methods. Hypothesis Open stabilization might produce better results than does arthroscopic stabilization in collision athletes. Study Design Cohort study; Level of evidence, 4. Methods Forty-eight shoulders of 46 collision athletes were enrolled for this study. The mean age of the patients at the time of surgery was 20 years, and the mean follow-up period was 72 months (range, 30-136 months). Sixteen shoulders underwent arthroscopic stabilization; 32 shoulders had open repairs. Results Visual analog scale, Rowe, and Constant scores improved after surgery, but no statistically significant difference was found between the arthroscopic and open repair groups. Thirty-seven athletes (83%) returned to near-preinjury sports activity levels (90% recovery) after operation. Two patients (4%) had subluxation and 6 (12.5%) had redislocation after surgery. The number of shoulders with postoperative subluxation or dislocation was 4 (25%) in the arthroscopic group and 4 (12.5%) in the open group (P = .041). Revision surgery was performed on 5 shoulders (10.4%). Conclusions There were 8 (16.5%) instances of postoperative instability among the collision athletes studied. The arthroscopic group yielded a higher failure rate than did the open group. The authors believe open stabilization to be a more reliable method for anterior shoulder instability in collision athletes.


American Journal of Sports Medicine | 2011

Arthroscopic Rotator Cuff Repair Using a Suture Bridge Technique Is the Repair Integrity Actually Maintained

Nam Su Cho; Bong Gun Lee; Yong Girl Rhee

Background: Suture bridge repair has been recognized to have superior biomechanical characteristics, as shown in previous biomechanical studies. However, it is not clear whether the tendon heals better in vivo after suture bridge repair. Purpose: To evaluate the clinical results and repair integrity after arthroscopic rotator cuff repair using a suture bridge technique for patients with rotator cuff tears. Study Design: Case series; Level of evidence, 4. Methods: One hundred twenty-three shoulders (120 patients) that underwent arthroscopic suture bridge repair for full-thickness rotator cuff tear were enrolled for this study. The mean duration of follow-up was 25.2 months (range, 16-34 months). The postoperative repair integrity was analyzed with use of magnetic resonance imaging (MRI) in 87 shoulders. According to the retear patterns on postoperative MRI, the cases were divided into type 1 (failure at the original repair site) or 2 (failure around the medial row). Results: At the last follow-up, the University of California at Los Angeles (UCLA) score improved from the preoperative mean of 13.2 points to 29.7 points (P < .001). The rotator cuff was completely healed in 58 (66.7%) of the 87 shoulders, and there was a recurrent tear in 29 shoulders (33.3%). The incidence of retear tended to increase with age older than 60 years at the time of surgery (P = .002). When there was a larger intraoperative tear, the rate of retear was also higher (P = .002). When the severity of preoperative fatty degeneration of the cuff muscles was higher, there was a greater chance of a recurrent tear (P < .001). The retear patterns on postoperative MRI in 29 shoulders with recurrent failures were classified as type 1 in 12 shoulders (41.4%) and type 2 in 17 shoulders (58.6%). The preoperative cuff tear size did not have an influence on retear patterns (P = .236), but the percentage of type 1 retear increased with the severity of fatty degeneration or muscle atrophy (P = .041, .023). Conclusion: Arthroscopic suture bridge repair of full-thickness rotator cuff tears led to a relatively high rate of recurrent defects. However, the mean 25-month follow-up demonstrated excellent pain relief and improvement in the ability to perform the activities of daily living, despite the structural failures. The factors affecting tendon healing were the patient’s age, the size and extent of the tear, and the presence of fatty degeneration in the rotator cuff muscle. The retear in cases with a suture bridge technique tended to be more frequently at the musculotendinous junction.


Arthroscopy | 2012

Effect of Two Rehabilitation Protocols on Range of Motion and Healing Rates After Arthroscopic Rotator Cuff Repair: Aggressive Versus Limited Early Passive Exercises

Bong Gun Lee; Nam Su Cho; Yong Girl Rhee

PURPOSE To compare range of motion and healing rates between 2 different rehabilitation protocols after arthroscopic single-row repair for full-thickness rotator cuff tear. METHODS Sixty-four shoulders available for postoperative magnetic resonance imaging (MRI) evaluation after arthroscopic rotator cuff repair were enrolled in this study. Aggressive early passive rehabilitation (manual therapy [2 times per day] and unlimited self-passive stretching exercise) was performed in 30 shoulders (group A) and limited early passive rehabilitation (limited continuous passive motion exercise and limited self-passive exercise) in 34 shoulders (group B). A postoperative MRI scan was performed at a mean of 7.6 months (range, 6 to 12 months) after surgery. RESULTS Regarding range of motion, group A improved more rapidly in forward flexion, external rotation at the side, internal and external rotation at 90° of abduction, and abduction than group B until 3 months postoperatively with significant differences. However, there were no statistically significant differences between the 2 groups at 1-year follow-up (P = .827 for forward flexion, P = .132 for external rotation at the side, P = .661 for external rotation at 90° of abduction, and P = .252 for abduction), except in internal rotation at 90° of abduction (P = .021). In assessing the repair integrity with postoperative MRI scans, 7 of 30 cases (23.3%) in group A and 3 of 34 cases (8.8%) in group B had retears, but the difference was not statistically significant (P = .106). CONCLUSIONS Pain, range of motion, muscle strength, and function all significantly improved after arthroscopic rotator cuff repair, regardless of early postoperative rehabilitation protocols. However, aggressive early motion may increase the possibility of anatomic failure at the repaired cuff. A gentle rehabilitation protocol with limits in range of motion and exercise times after arthroscopic rotator cuff repair would be better for tendon healing without taking any substantial risks. LEVEL OF EVIDENCE Level II, randomized controlled trial.


American Journal of Sports Medicine | 2011

Preoperative Analysis of the Hill-Sachs Lesion in Anterior Shoulder Instability: How to Predict Engagement of the Lesion

Seung Hyun Cho; Nam Su Cho; Yong Girl Rhee

Background: It has been reported that engagement of the Hill-Sachs lesion affects postoperative recurrence of anterior shoulder instability. However, no method has been recognized as an effective preoperative means to predict engagement of the Hill-Sachs lesion. Purpose: This study was undertaken to assess the diagnostic validity of computed tomography (CT) with 3-dimensional (3D) reconstruction to judge engagement of the Hill-Sachs lesion preoperatively. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: One hundred four consecutive patients (107 shoulders) who underwent arthroscopic Bankart repair for traumatic anterior shoulder instability were enrolled for this study. Preoperatively, CT with 3D reconstruction was performed on all patients to evaluate the size (width and depth measured on axial and coronal images), orientation (Hill-Sachs angle), and location (bicipital and vertical angles) of the Hill-Sachs lesion. Dynamic arthroscopic examination was made to confirm engagement of the Hill-Sachs lesion. Then the correlation between the results and measurements on CT images was statistically analyzed. Results: In cases of engaging lesions, the mean width was 52% (range, 27%-66%) and the mean depth was 14% (range, 8%-20%) of the humeral head diameter on axial images. The corresponding measurements on coronal images were 42% (range, 16%-67%) and 13% (range, 5%-24%), respectively. In cases of nonengaging lesions, the corresponding measurements were 40% (range, 0%-71%) and 10% (range, 0%-21%) on axial images and 31% (range, 0%-62%) and 11% (range, 0%-46%) on coronal images. The size of engaging Hill-Sachs lesions was significantly larger than that of nonengaging lesions on both axial and coronal images (P = .001, < .001, .012, .007). The Hill-Sachs angle was 25.6° ± 7.4° in engaging lesions, which was significantly larger than 13.8° ± 6.2° in nonengaging lesions (P < .001). The bicipital and vertical angles did not demonstrate significant correlation with engagement of the Hill-Sachs lesion (P = .850, .584). Conclusion: On CT with 3D reconstruction images, the engaging Hill-Sachs lesions were larger in size and more horizontally oriented to the humeral shaft than nonengaging lesions. The authors concluded that preoperative prediction of the engagement of the Hill-Sachs lesion, based on these findings, would be useful in planning additional procedures to treat a significant bone defect on the humeral head.


Clinics in Orthopedic Surgery | 2009

The Factors Affecting the Clinical Outcome and Integrity of Arthroscopically Repaired Rotator Cuff Tears of the Shoulder

Nam Su Cho; Yong Girl Rhee

Background The purpose of this study was to evaluate the functional and anatomic results of arthroscopic rotator cuff repair, and to analyze the factors affecting the integrity of arthroscopically repaired rotator cuff tears of the shoulder. Methods One hundred sixty-nine consecutive shoulders that underwent arthroscopic rotator cuff repair, had a postoperative MRI evaluation and were followed for at least two years were enrolled in this study. The mean age was 57.6 years (range, 38 to 74 years) and the mean follow-up period was 39 months (range, 24 to 83 months). Results The rotator cuff was completely healed in 131 (77.5%) out of 169 shoulders and recurrent tears occurred in 38 shoulders (22.5%). At the last follow-up visit, the mean score for pain during motion was 1.53 (range, 0 to 4) in the completely healed group and 1.59 (range, 0 to 4) in the group with recurrent tears (p = 0.092). The average elevation strength was 7.87 kg (range, 4.96 to 11.62 kg) and 5.25 kg (range, 4.15 to 8.13 kg) and the mean University of California at Los Angeles score was 30.96 (range, 26 to 35) and 30.64 (range, 23 to 34), respectively (p < 0.001, p = 0.798). The complete healing rate was 87.8% in the group less than 50 years of age (49 shoulders), 79.4% in the group over 51 years but less than 60 years of age (68 shoulders), and 65.4% in the group over 61 years of age (52 shoulders, p = 0.049); it was 96.7% in the group with small-sized tears (30 shoulders), 87.3% in the group with medium-sized tears (71 shoulders), and 58.8% in the group with large-sized or massive tears (68 shoulders, p = 0.009). All of the rotator cuffs with a global fatty degeneration index of greater than two preoperatively had recurrent tears. Conclusions Arthroscopic repair of full-thickness rotator cuff tears led to a relatively high rate of recurrent defects. However, the minimum two-year follow up demonstrated excellent pain relief and improvement in the ability to perform the activities of daily living, despite the structural failures. The factors affecting tendon healing were the patients age, the size and extent of the tear, and the presence of fatty degeneration in the rotator cuff muscle.


American Journal of Sports Medicine | 2008

Bridging the Gap in Immobile Massive Rotator Cuff Tears Augmentation Using the Tenotomized Biceps

Yong Girl Rhee; Nam Su Cho; Chan Teak Lim; Jin Woong Yi; Thimurayan Vishvanathan

Background Numerous operative techniques have been described for the treatment of massive rotator cuff tears with severe retraction where anatomical repair is impossible. Purpose To evaluate the outcome of massive rotator cuff tears repaired using the biceps interposition technique. Study Design Case series; Level of evidence, 4. Methods Between April 2000 and April 2004, 31 shoulders with irreparable massive rotator cuff tears and associated degenerative lesions of the biceps tendon were included for analysis. Open procedures were performed in 15 cases (open group), while 16 patients underwent arthroscopic procedures (arthroscopic group). The mean follow-up period was 32 months (range, 24-67 months). Results The overall University of California at Los Angeles score at the last follow-up was 31.1 points (range, 21-35). The clinical outcome was excellent in 15 (48.4%) and good in 13 (41.9%) cases. Three patients (9.7%) had poor outcome. There was 1 case of reoperation in the open group for a retear. The mean preoperative Constant score, which was 44.6 points (range, 8-70) in the open group and 51.8 points (range, 24-70) in the arthroscopic group, improved to 80.7 points (range, 37-88) in the former and 83.5 points (range, 57-96) in the latter. The University of California at Los Angeles score improved from preoperative means of 11.3 points (range, 6-16) and 13.6 points (range, 6-19) to 29.5 points (range, 9-33) and 32.6 points (range, 21-35), respectively. However, the differences between the scores in both the categories were not statistically significant (P = .412 and .198, respectively). According to the postoperative repair integrity analyzed with use of magnetic resonance imaging in 14 of 16 cases with arthroscopic augmentation, 9 (64.3%) presented complete healing. Conclusion The biceps tendon interposition technique for massive rotator cuff tears offers a possible improvement in the clinical outcomes and is comparable to that of conventional repair. As well, the augmentation technique using the tenotomized biceps as potential graft for rotator cuff tears is particularly useful in bridging the gap in immobile massive rotator cuff tears with posterior defects and retraction.


Arthroscopy | 2009

Arthroscopic Biceps Augmentation for Avoiding Undue Tension in Repair of Massive Rotator Cuff Tears

Nam Su Cho; Jin Woong Yi; Yong Girl Rhee

PURPOSE The purpose of our study was to evaluate the outcome of massive rotator cuff tears repaired by use of an arthroscopic biceps augmentation technique, interpositioning the tenotomized biceps tendon to bridge the gap between the torn edges of the cuff tendon. METHODS Sixty-eight shoulders with massive rotator cuff tears were included in this study. Arthroscopic rotator cuff repairs with the biceps augmentation technique were performed in 37 patients (group A), whereas 31 patients underwent repair without biceps augmentation (group B). The mean follow-up period was 21 months (range, 14 to 78 months) in group A and 20 months (range, 13 to 63 months) in group B. RESULTS The mean University of California, Los Angeles score improved from 14.1 points (range, 6 to 21 points) in group A and 13.9 points (range, 7 to 22 points) in group B preoperatively to 32.6 points (range, 22 to 35 points) and 30.3 points (range, 20 to 35 points) postoperatively, respectively (P < .001 and P < .001, respectively). However, the difference between the postoperative scores was not statistically significant (P = .198). At the last follow-up, group A showed better results than group B in forward flexion, external rotation, and internal rotation strength, with statistically significant differences (P = .017, P = .001, and P < .001, respectively). According to the postoperative repair integrity analyzed by use of magnetic resonance imaging, 58.3% of group A cases (14/24) and 26.3% of group B cases (5/19) had complete healing (P = .036). CONCLUSIONS An arthroscopic augmentation technique using the tenotomized biceps tendon was effective in achieving fewer structural failures, equivalent clinical outcomes, and significant improvement in muscle strength in comparison traditional arthroscopic repairs by avoiding undue tension in cases with massive rotator cuff tear.


American Journal of Sports Medicine | 2012

Arthroscopic Rotator Cuff Repair Using Modified Mason-Allen Medial Row Stitch Knotless Versus Knot-Tying Suture Bridge Technique

Yong Girl Rhee; Nam Su Cho; Chong Suck Parke

Background: When using a method of suture bridge technique, there may be a possibility of strangulation of the rotator cuff tendon at the medial row. The style of knots chosen to secure the medial row might conceivably be a factor to reduce this possibility. Purpose: To compare the clinical results and repair integrity of arthroscopic rotator cuff repair between a knotless and a conventional knot-tying suture bridge technique for patients with full-thickness rotator cuff tears and to evaluate retear patterns in the cases with structural failure after arthroscopic repair by magnetic resonance imaging (MRI). Study Design: Cohort study; Level of evidence, 2. Methods: After arthroscopic repair for medium-sized rotator cuff tears, 110 patients available for postoperative MRI evaluation at least 6 months were enrolled in this study. According to the repair technique, 51 shoulders were enrolled in a knotless suture bridge technique group (group A) and 59 shoulders in a conventional knot-tying suture bridge technique group (group B). The mean age at the time of the operation was 61.0 years (range, 44-68 years) in group A and 57.6 years (range, 45-70 years) in group B. The mean follow-up period was 21.2 months (range, 12-34 months) and 22.1 months (range, 13-32 months), respectively. Results: The Constant score of group A increased from the preoperative mean of 65.2 points to 79.1 points at the last follow-up (P < .001). The corresponding figures for group B improved from 66.6 points to 76.3 points (P < .001). The preoperative Shoulder Rating Scale of the University of California at Los Angeles (UCLA) score was 21.1 points in group A and 18.3 points in group B. The UCLA score at the last follow-up was 31.0 points in group A and 27.9 points in group B (P < .001, P < .001). Retear rate was significantly lower in group A (5.9%) than group B (18.6%) (P < .001). In group B, retear occurred at the musculotendinous junction in 72.7%, but group A had no medial cuff failure. Conclusion: In arthroscopic suture bridge repair of full-thickness rotator cuff tears, clinical results of both a knotless and a conventional knot-tying group showed improvement without significant difference between the 2 groups. However, the knotless group had a significantly lower retear rate compared with the conventional knot-tying group. A knotless suture bridge technique could be a new supplementary repair technique to conventional technique.


American Journal of Sports Medicine | 2009

Revision Open Bankart Surgery After Arthroscopic Repair for Traumatic Anterior Shoulder Instability

Nam Su Cho; Jin Woong Yi; Bong Gun Lee; Yong Girl Rhee

Background Only a few studies have provided homogeneous analysis of open revision surgery after a failed arthroscopic Bankart procedure. Hypothesis Open Bankart revision surgery will be effective in a failed arthroscopic anterior stabilization but inevitably results in a loss of range of motion, especially external rotation. Study Design Case series; Level of evidence, 4. Methods Twenty-six shoulders that went through traditional open Bankart repair as revision surgery after a failed arthroscopic Bankart procedure for traumatic anterior shoulder instability were enrolled for this study. The mean patient age at the time of revision surgery was 24 years (range, 16–38 years), and the mean duration of follow-up was 42 months (range, 25–97 months). Results The preoperative mean range of motion was 173° in forward flexion and 65° in external rotation at the side. After revision surgery, the ranges measured 164° and 55°, respectively (P = .024 and .012, respectively). At the last follow-up, the mean Rowe score was 81 points, with 88.5% of the patients reporting good or excellent results. After revision surgery, redislocation developed in 3 shoulders (11.5%), all of which had an engaging Hill-Sachs lesion and associated hyperlaxity (2+ or greater laxity on the sulcus sign). Conclusion Open revision Bankart surgery for a failed arthroscopic Bankart repair can provide a satisfactory outcome, including a low recurrence rate and reliable functional return. In open revision Bankart surgery after failed stabilization for traumatic anterior shoulder instability, the surgeon should keep in mind the possibility of a postoperative loss of range of motion and a thorough examination for not only a Bankart lesion but also other associated lesions, including a bone defect or hyperlaxity, to lower the risk of redislocation.

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Seung Hyun Cho

Kyungpook National University

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