PRINCIPLES, POSSIBILITIES AND LIMITATIONS OF ULTRASONOGRAPHY OF OSTEOFIBROUS PATHWAYS IN THE SHOULDER REGION .1.

The first part of this report includes basic morphological as well as morphometric data concerning osteo-fibrous pathways within the shoulde r region as determined by investigating a large number of anatomical s pecimens (286 macerated scapulae, 122 cadaver shoulders). Some parts o f these passages, either inaccessible by means of ultrasonography or a lready sufficiently dealt with in the relevant literature. are not tak en into consideration. This applies especially to the so called subacr omial space. As to the shape of the scapular notch, five different pat terns were found. The spinoglenoid notch appeared in four distinguisha ble types. According to the results of the measurements, type II (''sh allow'') and type IV (''V-shaped'') scapular notches can be regarded a s being predisposed to cause suprascapular nerve lesions. Contrary to what has previously been reported, nerve entrapment due to a partially ossified superior transverse scapular ligament seems to be unlikely. Cadaver dissections confirmed these observations, A comparison was mad e between the different types of scapular notches and the outlines of the scapular foramina (shapes one to nine) showing that a large indent ation does not necessarily result in a larger nerve passage. By reason of the restricted space, foramina classified as ''buttonhole-shaped'' (shape 5) must be regarded as a possible threat to the suprascapular nerve. In contrast, hypertrophy of the ligament as mentioned above cau sing nerve problems is, to say the least, doubtful. A spinoglenoid lig ament bridging the neck of the scapula was found in over half of the c ases studied. A clear relationship was detected between the coracoacro mial distance and the shape of the coracoacromial ligament: the greate r the distance the more arched was the band. Measurements of this dist ance in shoulder blades were also found to be highly dependent on the sex (significantly smaller in females). Side differences relative to t he aforementioned parameters did not occur. This also applies to the d imensions of the following structures: the long head of the biceps bra chii muscle, the intertubercular groove and the transverse humeral lig ament. The author considers the latter as having been underrated so fa r. Due to its constancy as well as its consistency, the ligament has t o be regarded as a valuable contribution to the protection of the bice ps tendon. A basic knowledge of the local anatomy is essential to sono graphic analysis.