Correspondence

Ultrasound Therapy for Calcific Tendinitis of the Shoulder

N Engl J Med 1999; 341:1237October 14, 1999

Article

To the Editor:

Ebenbichler and colleagues (May 20 issue)1 conclude that “in patients with symptomatic calcific tendinitis of the shoulder, ultrasound treatment helps resolve calcifications and is associated with short-term clinical improvement.” The primary outcome measure was changes from base line in the calcium deposits on radiography. Secondary outcomes included scores on a scale assessing the degree of pain perceived by the patients and scores on a scale assessing the patients' perceptions of their quality of life before and after treatment. Although the change in calcium deposits can be judged objectively, scores are subjective, and their validity can be questioned.

A clear understanding of the characteristics of the patients in the study is necessary in order to analyze and interpret subjective data. Studies of sex-based differences in responses to painful stimuli suggest that men and women respond differently to both pain and its treatment.2 Ebenbichler et al. did not specify the number of men and women in their study. Were there any sex-related differences in the responses?

Humayun J. Chaudhry, D.O.
Long Beach Medical Center, Long Beach, NY 11561

2 References

1. 1

   Ebenbichler GR, Erdogmus CB, Resch KL, et al. Ultrasound therapy for calcific tendinitis of the shoulder. N Engl J Med 1999;340:1533-1538
   Full Text | Web of Science | Medline

2. 2

   Miaskowski C. Women and pain. Crit Care Nurs Clin North Am 1997;9:453-458 abstract.
   Medline

Author/Editor Response

The authors reply:

To the Editor: We appreciate Dr. Chaudhry's careful consideration of our research. However, we do not entirely share his point of view. Prospective, sex-specific stratification before randomization would have been justified only had there been evidence that longitudinal changes (the primary end point) were more or less likely in men than in women, or vice versa.

The purpose of randomization is to control for imbalances that may occur when patients are assigned to the various groups. In our article, we did not report in detail the variables for which this goal was achieved. At base line, there were 11 men and 21 women in the ultrasound-treatment group and 11 and 18, respectively, in the control group. The respective numbers at follow-up were 10 and 21 and 10 and 15. A retrospective analysis of the longitudinal data showed no sex-specific differences in either calcifications or short-term clinical improvement.

Gerold R. Ebenbichler, M.D.
University Hospital of Vienna, 1090 Vienna, Austria

Karl L. Resch, M.D.
Forschungsinstitut für Balneologie und Kurortwissenschaft, 08645 Bad Elster, Germany

Citing Articles (1)

Citing Articles

1. 1

   P. Ogon, N. P. Suedkamp, M. Jaeger, K. Izadpanah, W. Koestler, D. Maier. (2009) Prognostic factors in nonoperative therapy for chronic symptomatic calcific tendinitis of the shoulder. Arthritis & Rheumatism 60:10, 2978-2984
   CrossRef