Internal impingement in the etiology of rotator cuff tendinosis revisited.

PURPOSE: The theory of internal impingement holds that, in overhead athletes, repeated contact between the undersurface of the rotator cuff and the posterosuperior glenoid rim leads to articular-sided partial-thickness rotator cuff tears and superior labral lesions. However, we have noted this same constellation of lesions in our general patient population. These recreational athletic patients do not routinely assume the position of extreme abduction and external rotation, and thus are unlikely to experience significant internal impingement forces. The goal of this study was to document the prevalence of superior labral lesions in patients being treated for partial-thickness undersurface rotator cuff tears. TYPE OF STUDY: Retrospective case series. METHODS: We retrospectively reviewed the records of 75 shoulders arthroscopically treated for partial-thickness articular-sided rotator cuff tears. With the exception of one professional tennis player, no patients were playing sports at a professional or major college level. No professional or collegiate throwing athletes were included. The prevalence of these lesions and their association with recreational athletics was noted. RESULTS: We found that 55 of 75 (73.3%) shoulders with articular-sided partial-thickness rotator cuff tears also had superior labral lesions. A statistically significant increased prevalence of superior labral lesions in the dominant shoulder was seen (P =.03). In addition, our patients who engaged in overhand throwing had significantly fewer superior labral lesions in the dominant shoulders than did nonthrowers (P =.017). CONCLUSIONS: The "kissing lesions" of undersurface rotator cuff tears and posterosuperior labral damage may be explained by mechanisms other than "internal impingement."

Iontophoretic administration of dexamethasone sodium phosphate for acute epicondylitis. A randomized, double-blinded, placebo-controlled study.

BACKGROUND: A better treatment modality is needed to control the pain of medial or lateral epicondylitis (tennis elbow). HYPOTHESIS: Dermal iontophoretic administration of dexamethasone sodium phosphate will be significantly more effective in controlling pain than a placebo in patients with medial or lateral elbow epicondylitis. STUDY DESIGN: Randomized, double-blinded, placebo-controlled study. METHODS: On six occasions, 1 to 3 days apart within 15 days, 199 patients with elbow epicondylitis received 40 mA-minutes of either active or placebo treatment. RESULTS: Dexamethasone produced a significant 23-mm improvement on the 100-mm patient visual analog scale ratings, compared with 14 mm for placebo at 2 days and 24 mm compared with 19 mm at 1 month. More patients treated with dexamethasone than those treated with placebo scored moderate or better on the investigator's global improvement scale (52% versus 33%) at 2 days, but the difference was not significant at 1 month (54% versus 49%). Investigator-rated pain and tenderness scores favored dexamethasone over placebo at 2 days. Patients completing six treatments in 10 days or less had better results than those treated over a longer period. CONCLUSIONS: Iontophoresis treatment was well tolerated by most patients and was effective in reducing symptoms of epicondylitis at short-term follow-up.