Standardisierte sonographische Untersuchung zur Klassifizierung der Instabilität des Schultereckgelenkes

Abstract

Anteroposterior X-ray views of both acromio-clavicular (AC-) joints with 10 kg weights in each hand are generally accepted for the diagnosis of Tossy I to III AC-joint separations. An analogue diagnosis can be made by standardized ultrasound examination. Ten individuals without AC-instability (Tossy I), eleven with Tossy II- and eight with Tossy III-instability were examined both radiographically and by B-mode ultrasound. AC-joint width was uniformly calculated by using an index (AC-index = AC-joint width of uninjured side/AC-joint width of injured side). The sonographically measured mean AC-index for Tossy I-stability was 1.0; sonographically 0.49 and radiographically measured 0.5 for Tossy II-injury; and sonographically 0.21 and radiographically measured 0.2 for Tossy III-instability. Statistical analysis resulted in significant differences for all mean AC-indices of the three groups (p < 0.0001). We conclude that ultrasound examination of AC-joint instability is as reliable as radiographic measurement. Standard X-rays of the shoulder remain mandatory to exclude fractures only. The decision for operative stabilisation of the AC-joint can be based on the side-effect free and cost-effective ultrasound examination of the grade of AC-joint instability (AC-index < 0.3 equivalent Tossy III).

The acutely injured acromioclavicular joint – which imaging modalities should be used for accurate diagnosis? A systematic review

“…Ultrasound has been shown to be able to reliably differentiate between sprain and rupture of the AC- and CC-ligaments and is widely available and inexpensive [ 16 , 20 , 21 ]. Therefore it is an interesting addition to the current diagnostic work up which is mainly based on conventional X-ray.…”

Fracture sonography of the extremities

“…Auch ein evtl. Klaviertastenphänomen kann sonographisch gesteuert geprüft werden [32,39]. Ebenso kann eine horizontale Instabilität geprüft werden [31].…”

Dynamic ultrasonography of the shoulder

“…Because a normal AC joint can show variable obliqueness and step-offs, AC joint space measurement on US can be problematic, and the criterion for widening (6 mm) established on radiographs [ 32 ] cannot be directly used on US [ 33 ]. Therefore, a comparison with the contralateral side is recommended to diagnose abnormal widening of the AC joint [ 34 ], and a relative measurement (AC index=AC joint space on the uninjured side/AC joint space on the injured side) is suggested [ 35 ]. The normal AC index is 1, and the AC index is lower in more widened and severely injured AC joints.…”