Background Calcific tendinopathy is a frequent cause of shoulder pain. Needling and lavage of the calcification is considered as the first line treatment after failure of NSAID or physiotherapy. X-ray remains the best imaging modality to diagnose and follow-up calcification changes after treatment. Ultrasound (US) has also shown its interest in the diagnosis of calcific tendinopathy and to guide the needling. It allows an evaluation of the calcification aspect and size. However, the value of US to follow-up calcification changes after needling is currently unknown.

Objectives The goal of our study was to evaluate the value of US in the follow-up of patients after needling and lavage of shoulder calcifications.

Methods Patients undergoing a needling and lavage of a shoulder calcific deposit were followed prospectively. Calcification size was measured on X-Ray and their aspect classified according to the French Arthroscopy Association (type A (sharp contours and a homogeneous structure); type B (sharp contours and a nonhomogeneous structure). Measurements were performed at the same time with US and calcifications were classified according to their echogenicity (arc-shaped; fragmented with or without shadowing, nodular). Changes in the X-ray and US at 3 months were studied.

Results Thirty patients were included, 20 female (66%), mean age 50 years (±11). On X-ray, calcifications were type A in 11 patients (36%) and type B in 19 patients (64%). Calcific deposits were mostly in the supraspinatus tendon (96%). Mean length, width and height of the calcific deposit were 15 mm (±6), 12 mm (±5.7) and 5.2 mm (±1.9) respectively. On US, calcification were arc shaped in 12 cases (40%), fragmented with shadowing in 15 (50%), without shadowing in one case and nodular in 2 cases (6.7%). Type A calcification on X-Ray were mainly arc shaped on US (80%) whereas type B on X-ray were fragmented or nodular on US in 79% of the cases. Bursitis was associated in 12 patients (40%). A significant correlation was found between the size of the calcification recorded on US and X-Ray (length (r=0.78), width (r=0.65) and height (r=0.59); p<0.01). A 3 months, 12 calcifications (40%) had completely disappeared on X-Ray, 3 (10%) were reduced between 50 and 90%, 9 (30%) reduced by less than 50% and (20%) had not changed. In contrast, only two patients had a complete disappearance of their calcific deposit on US. Calcifications became most of the time fragmented with (9; 30%) or without (12; 40%) acoustic shadowing. Calcific deposit remained arc shaped in only 2 patients. Bursitis was still present in 12 patients at 3 month.

Conclusions US seems a good imaging modality to follow-up patients with calcific tendonitis. Indeed, we found a good correlation between the sizes of the calcification assessed by US and X-ray as well as their radiological and US pattern. Three months after needling and lavage of the calcification, US was able to depict changes in morphology of the calcific deposit and could still detect calcifications even in patients with a complete disappearance of the calcification on X-Ray. In view of the lack of radiation for the physician and the patients, US could be of value in the follow-up of patients after treatment of a calcific tendinopathy.

Disclosure of Interest None declared