Protrusio Acetabuli and Total Hip Arthroplasty in Patients With Marfan Syndrome Savyasachi C. Thakkar, MD, Jared R.H. Foran, MD, Simon C. Mears, MD, PhD, and Paul D. Sponseller, MD Abstract: Our goals were (1) to quantify protrusio acetabuli in patients with Marfan syndrome who underwent total hip arthroplasty and (2) to identify clinical results and complications associated with total hip arthroplasty in those patients. We reviewed the preoperative radiographs of the 29 patients (38 hips) in our study and analyzed the related patient operative reports, postoperative records, and self-administered questionnaires (mean follow-up, 116 ± 102 months). The mean preoperative center-edge angle of Wiberg was 50.9° ± 14°. Loosening (3) and radiolucent lines (4) occurred in femoral but not acetabular components. The hips had 15 complications, including 8 reoperations. High questionnaire scores (82 ± 13 points) indicated good hip function regardless of preoperative protrusio severity. Keywords: protrusio acetabuli, Marfan syndrome, total hip arthroplasty, outcomes. © 2012 Elsevier Inc. All rights reserved. Marfan syndrome is an autosomal-dominant connective tissue disorder caused by mutations in the gene encoding the protein fibrillin 1 [1]. An estimated 30 000 individuals in the United States have Marfan syndrome, which affects 1 to 2 in 10 000 persons [1]. This syndrome presents with variable manifestations in multiple organ systems, such as ectopia lentis, aortic root dilatation, dural ectasia, and various skeletal abnormal- ities [2]. The skeletal manifestations of Marfan syn- drome are diverse [3-6]. The presence of protrusio is one of the skeletal criteria for the diagnosis of Marfan syndrome by the Ghent nosology [4], and some experts think that patients with Marfan syndrome may be at an increased risk for hip degeneration because of protrusio acetabuli [7-13]. Two recent studies have addressed the issue of protrusio acetabuli and Marfan syndrome. One has indicated that, in terms of natural history of disease progression, the prevalence and severity of protrusio acetabuli in patients with Marfan syndrome increases during the first 2 decades of life and then plateaus after 20 years of age [14]. It also found that protrusio acetabuli was not associated with severe hip dysfunction but caused decreased range of motion of the hip [14]. The second study indicated that a consequence of protrusio acetabuli is secondary osteoarthritis characterized by a loss of posteroinferior joint space as compared with superior joint space [15]. However, it is still unclear if protrusio acetabuli in the patient with Marfan syndrome is related to the need for total hip arthroplasty (THA). Hip arthroplasty in the patient with Marfan syndrome presents medical and surgical challenges. Patients with Marfan syndrome typically have other conditions, such as aortic root dilation, that might lead to higher medical complication rates after surgery. Protrusio acetabuli itself leads to more difficulty in placement of the acetabular component. The most common approach is the use of bone graft behind the cup to rebuild the acetabulum and lateralize the component. To our knowledge, there have been no studies, patient series, or isolated case reports that address the results of THA in the patient with Marfan syndrome. Our goals were (1) to quantify protrusio acetabuli in patients with Marfan syndrome who underwent THA and (2) to identify clinical results and the rate and type of complications after THA in patients with Marfan syndrome. Materials and Methods We received institutional review board approval before contacting patients for this retrospective study, From the Department of Orthopaedic Surgery, The Johns Hopkins University/Johns Hopkins Bayview Medical Center, Baltimore, Maryland. Submitted July 7, 2010; accepted August 6, 2011. The Conflict of Interest statement associated with this article can be found at doi:10.1016/j.arth.2011.08.010. This work was supported by a grant from the Doris Duke Charitable Foundation to The Johns Hopkins University School of Medicine to fund Clinical Research. Reprint requests: Paul D. Sponseller, MD, c/o Elaine P. Henze, BJ, ELS, Medical Editor and Director, Editorial Services, Department of Orthopaedic Surgery, Johns Hopkins Bayview Medical Center, 4940 Eastern Ave., #A665, Baltimore, MD 21224-2780. © 2012 Elsevier Inc. All rights reserved. 0883-5403/2705-0019$36.00/0 doi:10.1016/j.arth.2011.08.010 776 The Journal of Arthroplasty Vol. 27 No. 5 2012