著者
筒井 廣明 山本 龍二 安楽 岩嗣 三原 研一 今里 有紀彦 保刈 成
出版者
日本肩関節学会
雑誌
肩関節 (ISSN:09104461)
巻号頁・発行日
vol.15, no.1, pp.13-17, 1991-09-01 (Released:2012-11-20)
参考文献数
11

The shoulder joint is the most mobile joint in the body combined with a small glenoid and a large humeral head. This joint has been thought to be an unstable joint because of its anatomical structure and the recurrence rate from initial dislocations. Our opinion of this joint is that it has most distinguished stabilizing mechanisms for keeping a wide range of motion.1. The first stabilizing mechanismThis mechanism is the bony combination of the radius between the glenoid cavity and the humeral head. The anatomical study showed the radius of a cross section of the glenoid was 16.8 mm and of the humeral head 22 mm. The computation of the maximum permissible kinetic vector that enables the humeral head to be on the glenoid was 43°.2. The second stabilizing mechanismThe second mechanism is the function of the anterior capsule including the inferior glenohumeral ligament.The anterior capsule works involuntary in both its tension and direction as the centripetal force does against the shear force.3. The disadvantages of these two stabilizing mechanismsThe disadvantages of these two stabilizing mechanisms are; - Inefficiency against the increased anterior kinetic vector during the positioning of the upper extremities vertically against the glenoid- The decrease of bony structural intensity compared with other joints such as the hip joint.4. The third stabilizing mechanismThe third stabildzing mechanism is the function of the shoulder girdle.Its first function is the mobility of the scapula working as shock ab s orber against the share force that falls on the glenohumeral joint.The second is the function of the shoulder girdle muscles such as the pectoralis major and the deltoid.In conclusion, therefore, a normal shoulder joint should be the most distinguished joint with these stabilizing mechanisms physically and anatomically maintaining a wide range of motion.
著者
筒井 廣明 山本 龍二 安楽 岩嗣 三原 研一 今里 有紀彦 保刈 成
出版者
Japan Shoulder Society
雑誌
肩関節 (ISSN:09104461)
巻号頁・発行日
vol.15, no.1, pp.13-17, 1991
被引用文献数
3

The shoulder joint is the most mobile joint in the body combined with a small glenoid and a large humeral head. This joint has been thought to be an unstable joint because of its anatomical structure and the recurrence rate from initial dislocations. Our opinion of this joint is that it has most distinguished stabilizing mechanisms for keeping a wide range of motion.<BR>1. The first stabilizing mechanism<BR>This mechanism is the bony combination of the radius between the glenoid cavity and the humeral head. The anatomical study showed the radius of a cross section of the glenoid was 16.8 mm and of the humeral head 22 mm. The computation of the maximum permissible kinetic vector that enables the humeral head to be on the glenoid was 43&deg;.<BR>2. The second stabilizing mechanism<BR>The second mechanism is the function of the anterior capsule including the inferior glenohumeral ligament.<BR>The anterior capsule works involuntary in both its tension and direction as the centripetal force does against the shear force.<BR>3. The disadvantages of these two stabilizing mechanisms<BR>The disadvantages of these two stabilizing mechanisms are; - Inefficiency against the increased anterior kinetic vector during the positioning of the upper extremities vertically against the glenoid<BR>- The decrease of bony structural intensity compared with other joints such as the hip joint.<BR>4. The third stabilizing mechanism<BR>The third stabildzing mechanism is the function of the shoulder girdle.<BR>Its first function is the mobility of the scapula working as shock ab s orber against the share force that falls on the glenohumeral joint.<BR>The second is the function of the shoulder girdle muscles such as the pectoralis major and the deltoid.<BR>In conclusion, therefore, a normal shoulder joint should be the most distinguished joint with these stabilizing mechanisms physically and anatomically maintaining a wide range of motion.
著者
筒井 廣明 管 直樹 山口 光國 山本 龍二 三原 研一 保刈 成 上里 元 鈴木 一秀 大島 和 内川 友義
出版者
Japan Shoulder Society
雑誌
肩関節 (ISSN:09104461)
巻号頁・発行日
vol.19, no.2, pp.310-316, 1995

Purpose<br>The purpose of this study is to recognize the effect of exercise for cuff muscles using EMG.<br>Materials and Methods<br>5 healthy young men, aged from 17 to 29 yrs., were examined. The "resisted external rotation"exercise for the infraspinatus muscle was estimated. The Cuff-Y exercise with a yellow Thera-Band and F. W. Jobe's strengthening exercise with a 1.5kg weight were compared. During the exercises, the infraspinatus, the supraspinatus, the deltoid, and the middle fiber of the trapezius were examined with EMG. The EMG was recorded continuously from the beginning for 5 minutes.<br>Results<br>The exercise withe the yellow Thera-Band could dominate the activity of the infraspinatus muscle compared to other muscles. As for the exercises with a 1.5kg weight, it was difficult to keep the activity of the infraspinatus advantageous and the 5 volunteers demonstrated five different patterns of muscle activity. Furthermore, the relative activity of the infraspinatus gradually decreased with time.<br>Conclusion<br>Exercises for cuff muscles should be carried out to keep the dominant activity of the targeted muscle compared to other muscles. The setting of the load and time limit both failed and the purpose of the exercise could not be attained.
著者
山口 光國 筒井 廣明 山本 龍二 三原 研一 保刈 成 鈴木 一秀 上里 元 大島 和 内川 友義 菅 直樹 牧内 大輔
出版者
日本肩関節学会
雑誌
肩関節 (ISSN:09104461)
巻号頁・発行日
vol.20, no.2, pp.325-328, 1996-11-30 (Released:2012-11-20)
参考文献数
4

PurposeWe investigated the muscle strength of the scapulothoracie joint which is apt to be affected by the position of other joints.
著者
筒井 廣明 山口 光國 山本 龍二 三原 研一 保刈 成 鈴木 一秀 上里 元 大島 和 内川 友義 菅 直樹 牧内 大輔
出版者
日本肩関節学会
雑誌
肩関節 (ISSN:09104461)
巻号頁・発行日
vol.20, no.2, pp.337-340, 1996-11-30 (Released:2012-11-20)
参考文献数
6
被引用文献数
1

[Purpose]Cuff exercises are usually performed to improve the shoulder function and to keep the condition of the shoulder of throwing athletes. Thus, there are a large number of athletes who could not acquire the expected effects of the exercises. In this study, we examined the estimation of the cuff function and the daily exercises of the athletes electromyographically.