The influence of ultrasound guidance in the rate of success of acromioclavicular joint injection: an experimental study on human cadavers

Background: Injections of the acromioclavicular joint (ACJ) are performed routinely in patients with ACJ arthritis, both diagnostically and therapeutically. The aim of this prospective controlled study was to estimate the frequency of successful intra-articular ACJ injections with the aid of sonographic guidance versus non-guided ACJ injections. Materials and methods: A total of 80 cadaveric ACJs were injected with a solution containing methylene blue and subsequently dissected to distinguish intra-from peri-articular injections. In 40 cases the joint was punctured with sonographic guidance, whereas 40 joints were injected in the control group without the aid of ultrasound. Results: The rate of successful intra-articular ACJ injection was 90% (36 of 40) in the guided group and 70% (28 of 40) in the non-guided group. Ultrasound was significantly more accurate for correct intra-articular needle placement (P=.025). Discussion: The use of ultrasound significantly improves the accuracy of ACJ injection. Level of evidence: Basic Science Study, Anatomic Study, Cadaveric Model. (C) 2012 Journal of Shoulder and Elbow Surgery Board of Trustees.