Paxinos test is named for Anastasios Paxinos from the University of New South Wales in Sydney Australia. It's used by doctors, physical therapists, and athletic trainers to test for injury of the acromioclavicular (AC) joint.

The examiner presses two bones together: the clavicle (collarbone) and the acromion. The acromion is a bony projection that comes off the back of the shoulder blade. It curves around to the front over and above the shoulder joint and meets the clavicle in front of the shoulder.

The test is done with the patient sitting and the involved arm down at the side. The examiner places his or her hand over the top of the shoulder. The thumb presses against the back of the acromion. The index finger of the same hand presses against the clavicle. The pressure from the front and back of the shoulder is directed in toward the body.

A positive Paxinos test should be followed up by a bone scan. Dr. Paxinos's studies show when both tests are positive in a patient with shoulder pain, the diagnosis of AC joint pain is virtually certain.