Intraoperative wound cultures: their value and long-term effect on the patient.

A series of 856 total hip arthroplasties in 681 consecutive patients was reviewed in an attempt to determine what variables are significant in identifying the patient "at risk" for postoperative wound infection. Variables such as sex, age, preoperative diagnosis, laterality, and wound closure had no influence on the results of the intraoperative cultures. No statistical correlation was found between these factors and the patient's outcome. However, in patients who had undergone previous hip surgery long-term results were not as favorable as those in patients with per primam operations (12.0% versus 8.5%, respectively, had long-term postoperative problems). The most significant finding of this study was in the area of intraoperative culture results versus the patient's end-result. Here, it was found that when culture results were subdivided into zero, one, or two (both opening and closing) positive cultures, zero or one positive culture had no effect on patient outcome. However, two positive cultures were indicative of complications (p less than 0.001). One-third of these hips either developed loosening or long-term postoperative pain, of which 75% went on to become infected. The "at risk" patient was thus defined as the patient who had positive intraoperative cultures.