US-guided percutaneous treatment of shoulder calcific tendonitis: some clarifications are needed.

We read with great interest the article (1) by Dr Serafini and colleagues on ultrasonography (US)-guided percutaneous treatment of calcific tendinosis, which appeared in the July 2009 issue of Radiology. However, we have some concerns about their article: Because calcific tendonitis is a self-limited condition, the assessment of outcomes in the treated population without an adequate control group could introduce a bias in the determination of response to therapy. In addition, a more objective imaging evaluation with radiography (2) or US (3) is required to determine the outcome of treatment and compare it with others. Without an adequate control, it is not obvious whether the reported success is due to spontaneous improvement, the local anesthetic, the two-needle treatment, the applied steroid, or a combination of factors. The study group is not well characterized. The classification of calcific tendinosis (eg, as done by Gärtner and Simons [2]) has not been reported. Type III calcifications in the Gärtner and Simons classification system showed a high probability of spontaneous resolution (4), and patients with them have been excluded in a number of clinical trials (5–7). We are surprised at the complete absence of calcified supraspinatus tendons in this series of patients. There are limited clinical follow-up data. Although this is a case control study, the 1-month, 3-month, and 1-year results may have clinical relevance. We are also concerned with the comparison of results at 5 years to those at 10 years since so many patients were lost to follow-up. Moreover, the reason for these losses is not explained. We hope the authors can clarify their rationale for the study design limitations we have noted and clarify their approach to follow-up.