Introduction

As opposed to the hip joint, where most of the femur head is surrounded by the osseous ace tabular fossa and thus~ stabilized by bony contact. Stabilization of the shoulder joint IS achieved dynamically, i.e. by the joint capsule with its ligaments (labral-ligamentous complex) and the tendons of the moving muscles. Thus the soft tissues are affected far more often than the bony structures in shoulder injuries even in sports. Therefore functional aspects have to be taken into consideration for rehabilitation after conservative as well as after surgical! Treatment of sports injuries Principles or shoulder rehabilitation shall be demonstrated for the two most common lesions - i.e. subacromial syndromes and shoulder instability.

Subacromial Syndrome

During abduction of the arm, a sliding of the rotator cuff or the subacromial bursa respectively underneath the coraco-acromial arch Is only possible without compression if there is a muscular balance between those muscles that pull the humeral head upwards (elevators) and those whose force vector Is directed downwards (depressors). The main elevator is the deltoid, furthermore triceps brachii, short head of biceps brachii, and coraeobrachialis. Antagonists as far as depression of the humeral head is concerned are primarily subscapularis, infraspinatus, and teres minor, but also supraspinatus. long head of biceps brachii, teres major and latissimus dorsi. In addition, the weight of the arm pulls the head caudally.

If a subacromial lesion of any kind is present, a refectory inhibition of the muscles affected due to pain will result in a weakness of the humeral head depressors In case of a rotator cuff tear, the strength is also reduced mechanically. The resulting muscular imbalance between elevators and depressors of the humeral head favouring those muscles pulling in a crania1 direction will cause an increased compression of the damaged rotator cuff underneath the coracoacromial arch thus resulting in a vicious circle pain - strength reduction - compression - pain. Therefore, the aim of functional rehabilitation of subacromial syndromes consists in the restoration of muscular balances between elevators and depressors of the humeral head by strengthening the depressors.

Shoulder Instability

As far as instability of the shoulder joint is concerned, the goal of functional rehabilitation will be a muscular balance between internal! and external rotators of the shoulder. Internal! rotators are subscapularis in first place, but also pectoralis major. the anterior segment of the deltoid, latissimus dorsi, and teres major. External! Rotators are infraspinUtu5. Supraspinatus, teres minor, and the posterior segment of the deltoid.

In this context the position of the scapula is very important. In most patients a protraction of the shoulder is to be found cither as a relieving posture or if the minor pectoral] is shortened. Biomechanically, the neutral position of rotation in the sfinulder drawn in an anterior dircetion is shifted inwards. Even if the lower arm appears to be in a neutral position, it really is externally rotated in the glenohumeral joint in case of a protracted shoulder, thus putting additional strain on the anterior capsule and labrum that are injured already In order to achieve rehabilitation of the unstable shoulder, the scapulothoracal muscles have to be included in the training program, i.e. through strengthening of the rhomboids and stretching of minor pectoral and trapezius.

PNF in Rehabilitation

Since movements occur in three-dimensional space, we prefer functional physiotherapy on a neuropsychological basis applied in diagonals like proprioceptive neurornuscular facilitation (PNF). This technique will! produce better results for enhancement o muscular strength and athletic performance than weight training, as was demonstrated by NELSON et al. in 1986, comparing the effects of PNF and weight training. According to their study, the increase of knee and elbow extensor strength, throwing distance. and vertical jump in 30 college women after different types of training for 8 consecutive weeks was bigger through PNF in all four parameters tested. In conclusion, PNF might be superior to weight training and thus be a better modality for athletic conditioning and injury rehabilitation. PNF can be used in shoulder rehabilitation for instabilities as well as for subacromial pain.