ANTEROPOSTERIOR INSTABILITY OF THE DISTAL CLAVICLE AFTER DISTAL CLAVICLE RESECTION

Resection of the lateral end of the clavicle disrupts the acromioclavi cular articulation and creates the potential for abnormal postoperativ e motion, Seventeen isolated distal clavicle resections were reviewed to assess translation of the acromioclavicular articulation in the ant eroposterior plane and its relationship to patient outcome, Stress rad iographs were used to quantitate the translation of the distal clavicl e and the amount of bone resected, Radiographs of the contralateral sh oulder served as a control, Patients completed a questionnaire on shou lder function and pain and were examined preoperatively and postoperat ively. The total translation (anterior plus posterior) in the anteropo sterior plane averaged 8.7 mm (range, 3-21 mm) for surgically treated shoulders and was significantly greater than that for the contralatera l shoulders (mean, 3.2 mm; range, 1-6 mm), Patients' postoperative vis ual analog pain scales correlated with the magnitude of anteroposterio r translation, The amount of translation and the postoperative pain sc ores did not correlate with the apparent joint space seen on radiograp hs after surgery, The correlation of pain scores with the amount of tr anslation shows that excessive anteroposterior instability of the dist al clavicle can cause postoperative shoulder pain and poor surgical ou tcome.