RESUMEN
The role of acromioclavicular (A-C) arthritis in stage 2 and 3 impingement syndromes was investigated in this study. Twenty-seven patients with stage 2 and 3 impingement syndrome were evaluated both clinically and radiologically for the presence of A-C arthritis. Patients with A-C arthritis who were treated by conservative or surgical methods were rated before and after therapy according to the University of California at Los Angeles (UCLA) shoulder rating scale. The follow-up period ranged from 7 to 16 months, with an average of 13 months. A-C arthritis was diagnosed in 21 of 27 patients (one grade 2 and 20 grade 3, according to Kellegren). Clinical and radiological evaluation of these 21 patients revealed A-C joint pain and a positive lidocaine injection test in all (100%), a positive horizontal adduction test in 20 (95.2%), decreased joint space in 18 (85.75%) and osteophytes in 11 (52.4%). Surgical treatment was considered for 12 A-C arthritis patients; and distal clavicle resection was performed in 11 of these cases. The average score measured by the UCLA rating scale increased from 13 to 28 in the group treated with surgery (satisfactory result), and from 10 to 13 in the group treated with conservative therapy (unsatisfactory result). The results of this study may be interpreted as demonstrating that A-C arthritis is a common etiologic factor in chronic impingement syndromes and its co-existence has a strategic importance in the choice of treatment method. Surgical resection of the distal clavicle should be considered in the presence of this pathology since this technique provides excellent results in pain relief and appears to be superior to conservative therapy in these cases.