• Clinics in Shoulder and Elbow
• /
• v.16 no.1
• /
• pp.1-9
• /
• 2013

Purpose: The purpose of this study is to analyze the correlation between the degree of torn rotator cuff as recorded by MRI and degenerative change of acromion and greater tuberosity of humerus determined by simple radiographs. Materials and Methods: Of the 518 cases included in this study, a group of 234 cases had a chronic rotator cuff tear and a control group of 284 cases had an intact rotator cuff in shoulder MRI. The degree of degenerative changes was classified according to the length of spur and morphological change of acromion and greater tuberosity through the true anteroposterior simple radiograph in supraspinatus outlet view. The degree of tear (partial-thickness or full-thickness tear) and the size of complete rotator cuff tear were analyzed according to the MRI findings of shoulder. The authors also evaluated the correlation between the degree and size of torn rotator cuff and the degenerative change of acromion and greater tuberosity. Results: There were significant differences in the size and extent of torn rotator cuff according to the age, sex and degenerative change of acromion and greater tuberosity of humerus (p<0.001). More degenerative changes of acromion and greater tuberosity in simple shoulder radiographs showed the increased degree and size of torn rotator cuff (p<0.001). In addition, the higher degree and larger size of torn rotator cuff were noted in older age subjects (p<0.001) and in the female group (p<0.001). Conclusion: More degenerative changes of acromion and greater tuberosity in simple shoulder radiographs showed the increased degree and size of torn rotator cuff. Therefore, if a high degree of degenerative change of the acromion and greater tuberosity on simple radiograph is noted, the possibility of degenerative rotator cuff tear should be considered. In addition, the age and sex could be associative factors for larger size of torn rotator cuff.

• Clinics in Shoulder and Elbow
• /
• v.15 no.1
• /
• pp.16-24
• /
• 2012

Purpose: This study was designed to investigate the rate of incidence, location and the clinical value of the rotator cuff retear by analyzing MRI scans, which was taken after an arthroscopic rotator cuff repair. Materials and Methods: This study included a total of 109 patients, who underwent a shoulder MRI scan after an average of 10.6 months later from the arthroscopic rotator cuff repair. We only defined the 'retear' when the Sugaya type IV and V was observed in the sagittal section of the MRI. The location of the retear was divided into the medial and lateral areas by the site, which was 1 cm medial to the anchor insertion. We investigated the incidence rate and the location of the retear, in terms of the age, sex, initial tear size and the suture method. Also, we compared the functional score of the retear group and the non-retear group, after an average of 13.9 months follow-up. Results: There were 38 of the 109 patients that showed the rotator cuff retear. Of these patients, 25 were male patients, and 13 were female patients. Of the 38 patients with the rotator cuff retear, 21 patients were included in the <3 cm retear group, and 17 were included in the ${\geqq}3$ cm retear group. At the end of the follow up period, all 109 patients showed a statistical significant improvement in the shoulder functional score. Conclusion: According to the follow up of the MRI scan, which was taken after the rotator cuff repair, the retear rate reached 34.9 %, and there were no significant differences on the age and the suture method. More rotator cuff retear occurred in male patients, and the initial tear size was positively correlated with the incidence rate of the rotator cuff retear. Also, the retear was more frequently observed at the medial side. That is because when the suture was performed, excessive tension was loaded on the medial side of the suture site.

• Clinics in Shoulder and Elbow
• /
• v.12 no.1
• /
• pp.38-43
• /
• 2009

Purpose: The purpose of this study was to assess the efficacy of MR arthrography to detect partial thickness rotator cuff tears. Materials and Methods: One hundred and seventy seven patients with a high suspicion for rotator cuff disease were studied by performing MR-arthrography and subsequent arthroscopy. The ability of MR-arthrography to detect partial thickness tears was evaluated according to the location of the tears. We determined the correspondence between the measurements of the articular side partial tears on MR arthrography and those on the arthroscopic findings. Results: The arthroscopic diagnosis of partial thickness rotator cuff tears was divided into 3 groups according to their location. There were 63 cases on the articular side, 41 cases on the bursal side and 20 cases on both sides. The sensitivity of MR-arthrography was 82% for the articular side tears and 11% for the bursal tears. The specificity was 88% for the articular side tears and 100% for the bursal tears. MR-arthrographic measurement correctly predicted 72% in 28 repaired cases of 56 articular side partial thickness tears. Conclusions: MR-arthrography may be a reliable tool for diagnosing articular side partial thickness rotator cuff tears, but it has limitations for bursal side tears.

• The Journal of Korean Orthopaedic Ultrasound Society
• /
• v.6 no.2
• /
• pp.53-59
• /
• 2013

Purpose: The aim of this study wasto evaluate the comparison of CT arthrography and ultrasonography, confirmed by the arthroscopic finding in patients with rotator cuff disease. Materials and Methods: We evaluated fifty seven patients with rotator cuff disease underwent CTA and arthroscopy, and twenty eight patients had taken ultrasonographyadditionally. The diagnostic value and prediction for tear size between CTA and ultrasonography were evaluated, as compared to arthroscopic findings. Results: CTA showed a sensitivity of 86.2% and a specificity of 100% in full thickness tear ofsupraspinatus, a sensitivity of 58.3% and a specificity of 87.8% in partial-thickness tear. CTA demonstrated good diagnostic value for full thickness tear, but there was relatively lower value for partial-thickness tear. Ultrasonography showed a sensitivity of 84.6% and a specificity of 86.7% for diagnosing in full thickness tear, a sensitivity of 84.6% and a specificity of 73.3% in partial-thickness tear. Ultrasonography provided good diagnostic value, but, there is lesser accurate result for prediction of tear size. Conclusion: CTA showedgood diagnostic tool of detection full-thickness tear of rotator cuff disease and predicting of tear size. Comparing with ultrasonography, CTA was inferior for detection of partial-thickness tear, but, provided better estimation for tear size.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.11a
• /
• pp.481-487
• /
• 2011

This paper provides a comparison between finite element analysis results and test data of rupture disc. Rupture disc is safety device of high pressure equipment. Rupture disc of solid rocket motor is a device to control rupture pressure. Rupture discs were made of AISI 316L. By the elastic-plastic analysis, the stress limit of rupture discs were compared to the test results. The results can be used to control the rupture pressure by the change of the disc size.

• Clinics in Shoulder and Elbow
• /
• v.10 no.1
• /
• pp.42-49
• /
• 2007

Purpose: To compare the thickness of the repaired full-thickness rotator-cuff tear to that of normal rotator-cuff in young and old persons and evaluate the relationship between the tear size and the repaired thickness in the full-thickness tear using MRI. Materials and Methods: The thickness of the rotator-cuff of the repaired full thickness tear(age: $45{\sim}77$, mean 63.3 years, 19 patients: group 1) were compared with those of old intact patients(age: $46{\sim}69$, mean 57.9 years, 23 patients: group 2) and young intact patients (age: $18{\sim}30$, mean 23.3 years, 22 patients: group 3). The tear length and width was measured in oblique coronal and oblique sagittal view of MRA, respectively, and the thickness was measured in coronal oblique view 15mm anterior to the posterolateral margin of the glenoid. Correlation between the preoperative tear size (the bigger one between the length and the width) and the postoperative thickness in group 1 was also evaluated statistically. Results: The postoperative rotator-cuff thickness in group 1 was 3.0 mm in average, which was inversely proportional to the preoperative tear size (P<0.001). The rotator-cuff thickness was 3.9mm in group 2 and 5.0mm in group 3, and there was statistically significant difference among the three groups(P<0.05). Conclusion: The rotator-cuff thickness decreases with age and the postoperative thickness in the full-thickness tear was inversely proportional to the tear size, smaller than that of the intact rotator-cuff.

• The Academic Congress of Korean Shoulder and Elbow Society
• /
• 2007.03a
• /
• pp.109-109
• /
• 2007

• The Journal of Korean Orthopaedic Ultrasound Society
• /
• v.1 no.1
• /
• pp.23-26
• /
• 2008

Ultrasonography (USG) is widely accepted diagnostic method for the rotator cuff tear. The availability, low cost, easy to access is main factors that favor USG as a primary diagnostic modality for various cuff disorders. We experienced a case of discrepancy between USG, MR arthrography (MRA) and arthroscopic examination. Seventy four year old female patient complained of right shoulder pain. USG depicted rotator cuff tear with the size of 1cm, and MRA demonstrated about 3cm sized tear. Complex massive tear with delamination of degenerated rotator cuff was identified in the arthroscopic examination. When we encounter a patient who has loss of rotator cuff power or severe symptom than findings of USG, MRA or repeat USG is warranted. We report a case of discrepancy between examination modalities with brief review of the literature.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.10 no.2
• /
• pp.61-68
• /
• 2011

Purpose: We evaluated the clinical outcome after arthroscopic repair in full thickness rotator cuff tears with and without delamination. Materials and Methods: From March 2006 to October 2008, we included 48 consecutive shoulders (31 males, 17 females; mean age 57.6 years; 45~68) who had arthroscopic double row repair for fullthickness tears of the rotator cuff. Mean rotator cuff tear size was 2.8 cm (range: 1.2~3.6) and the techniques of tendon-to-bone fixation varied according to the presence of delamination; separate row fixations of bursal and articular layer were used in delaminated tear. The mean follow-up was 26 months (range: 18~33) and functional and structural results were evaluated by American Shoulder and Elbow Surgeons (ASES), University of California at Los Angeles (UCLA) scale, isokinetic strength testing and magnetic resonance imaging (MRI) obtained mean 8 months (range:6~13) postoperatively. The patterns of delamination, age, sex, symptom duration, size of tear, satisfaction rate, retear rate ware compared and significance was set at p values < 0.05. Results: Postoperative functional shoulder score improved significantly in 44 shoulders (91.7%). Delamination was observed in 15 shoulders (31%) and it extended proximally and posteriorly in the majority of shoulders, and the articular layer was thicker (8/15, 53%) and more retracted (9/15, 60%) compared with the superficial bursal layer. Final follow up functional shoulder scores showed no differences between non-delaminated and delaminated tears and the presence of delamination had no correlations with sex, symptom duration, tear size and satisfaction rate, however, older age had more delaminated tears (p=0.041). Follow up MRI in 29 shoulders revealed that fourteen (48%) shoulders had complete healing; nine (31%), partial healing; six (21%), complete retear but the half of the retear group showed favorable clinical results. 79% (15/19) in non-delaminated tear and 80% (8/10) in delaminated tear were judged as healed tendon on MRI and double-layer double row repairs in delaminated tears resulted in nearly same rate of structural integrity of single-layer double row repairs (p=0.165). Conclusion: The incidence of delamination in our series was 31% and older age had more delaminated tears. Sex, symptom duration, preoperative size of the tear, functional results and satisfaction rate had no significant correlations with the presence of delamination. Nearly the same postoperative structural integrity was noted in both delaminated and non-delaminated tears.

• Clinics in Shoulder and Elbow
• /
• v.12 no.2
• /
• pp.199-206
• /
• 2009

Purpose: Our goal for this study was to prospectively evaluate the functional & structural outcomes, by means of CT arthroscopy, of arthroscopic double-row fixation for treating rotator cuff tear. We also attempted to determine the variants that affect the functional & structural outcomes. Materials and Methods: Twenty seven consecutive patients underwent arthroscopic rotator cuff repair with double-row fixation. The average age at the time of the operation was fifty six years. The preoperative and postoperative examinations consisted of determining the Constant score, the score for the visual analogue scale for pain, the UCLA score, the American Shoulder and Elbow Surgeons (ASES) score, as well as a full physical examination of the shoulder. Preoperative MR arthrography was used to evaluate the integrity and atrophy of the rotator cuff. We measured the intraoperative tear size in the sagittal and coronal planes. Postoperative CT arthrography was used at one year postoperatively to evaluate the integrity and atrophy of the repaired tendons and muscles. Results: Preoperative MR arthrography revealed an average 29.22 mm tear size in the sagittal plane and an average 22.72 mm tear size in the coronal plane. Twelve cases of supraspinatus muscle atrophy and two cases of infraspinatus atrophy were observed on the preoperative MR arthrography. The average clinical outcome scores all significantly improved at the time of follow-up. At a mean of one year postoperatively, CT arthrography revealed 48.1% of the shoulders had healed, 11.1% showed incomplete healing and 40.7% showed retear of the repaired tendon. Conclusion: Arthroscopic double-row repair can result in improved clinical outcomes and good patient satisfaction. However, the problems about how to enhance healing of the repaired tendon still remain.