Correlation between aspiration of calcific rotator cuff tendinopathy and morphology on imaging.

Background: Calcific rotator cuff (RTC) tendinopathy is a self-limited, atraumatic cause of shoulder pain. Ultrasound-guided percutaneous needling and aspiration (USPNA) can be used when other nonoperative treatments fail.

Objective: To determine if there is an association between morphology of RTC calcifications on imaging and the ability to aspirate calcifications.

Design: Case series.

Setting: Tertiary orthopedic institution.

Patients: A total of 272 patients who underwent USPNA for symptomatic calcific RTC tendinopathy and had available imaging and clinical data.

Interventions: Imaging was categorized using Gärtner-Heyer (x-ray), Farin-Jaroma (ultrasound), and Chiou (ultrasound) morphological classifications.

Main outcome measures: Percentages of successful and unsuccessful aspirations were calculated.

Results: There were 292 USPNA cases; 170 (58.2%) aspirations were successful. Inter-rater reliability was almost-perfect for Farin-Jaroma and Chiou classifications (kappa: 0.92-1.00; p < .001) and fair-to-moderate for Gärtner-Heyer classifications (kappa: 0.38-0.74; p < .001). When applying the Gärtner-Heyer classification, 92/134 (68.7%) type I, 65/117 (55.6%) type II, and 10/35 (28.6%) type III calcifications were successfully aspirated (p < .001). Six calcifications could not be classified. No statistical difference was appreciated when using Farin-Jaroma (p = .939) or Chiou (p = .524) classifications. The mean calcification size for successful aspirations was significantly larger than that for unsuccessful aspirations (16.7 ± 6.4 mm vs. 13.4 ± 7.5 mm; p < .001), although there was no difference in ability to aspirate single versus multiple calcifications. The regression analysis showed an association between increasing calcification size and greater odds of aspiration success (10% increase; p < .001). Compared with type I Gärtner-Heyer classifications, type II and type III were associated with decreased odds of aspiration success (64% and 91% decreases, respectively; p ≤ .003).

Conclusions: Gärtner-Heyer classification was associated with the ability to successfully aspirate calcifications; type I calcifications were most frequently aspirated. Larger calcifications were also more frequently aspirated successfully. These factors may improve patient selection for USPNA. Further studies are needed to explore whether imaging classifications of RTC calcifications are correlated with patient-reported outcomes following USPNA.