Acute pseudo-obstruction of the colon (Ogilvie syndrome) results in massive colonic dilatation that may lead to a life-threatening perforation. This complication is known to occur after arthroplasty of the hip, yet the prevalence of the complication and its effects on the outcome of the procedure are unknown. We reviewed the records of thirty patients (mean age, 74.3 years; range, fifty-six to ninety years) in whom acute colonic pseudo-obstruction developed after hip arthroplasty between 1984 and 1993. During this ten-year period, 10,468 hip arthroplasties were performed at our institution; therefore, the prevalence of acute colonic pseudo-obstruction was 0.29 per cent. The most common presenting symptom was abdominal distention, which occurred a mean of 3.5 days (range, one to eleven days) postoperatively and was noted in twenty-seven of thirty patients. Nausea (fourteen patients), vomiting (eight patients), and abdominal pain (two patients) were observed less frequently. Twenty-one associated medical complications, including pulmonary embolism (four patients), upper gastrointestinal bleeding (three patients), and deep infection (not evident intraoperatively) at the site of the arthroplasty (two patients), developed in fifteen patients. Eighteen of the twenty-one complications occurred after the onset of colonic pseudo-obstruction. The associated medical problems resulted in four deaths (13 per cent). Recognition by the orthopaedic surgeon of the presenting features of acute colonic pseudo-obstruction is important in order to facilitate prompt initiation of treatment, which may hasten recovery and reduce the morbidity and the mortality associated with this complication.