A Fluoroscopic Grid in Supine Total Hip Arthroplasty Improving Cup Position, Limb Length, and Hip Offset Jeremy M. Gililland, MD, Lucas A. Anderson, MD, Shannon L. Boffeli, APRN, Christopher E. Pelt, MD, Christopher L. Peters, MD, and Erik N. Kubiak, MD Abstract: We hypothesized that use of a novel fluoroscopic grid would decrease operative time and component positioning variability during anterior supine total hip arthroplasty (THA). We reviewed 99 anterior supine THAs: 39 using a fluoroscopic grid, and 60 using fluoroscopy alone. Goals were cup abduction of 40° ± 10° and limb length and hip offset within 10 mm of the contralateral side. Surgical time was decreased in the study group (79 vs 94 minutes, P = .002). In the study group, more components met the goal for cup abduction (97% vs 83%, P = .046), limb length (100% vs 88%, P = .04), hip offset (85% vs 67%, P = .047), and all 3 combined (82% vs 52%, P = .002). We demonstrated decreased component positioning variability during anterior supine THA with assistance of a fluoroscopic grid. Keywords: total hip arthroplasty, fluoroscopic grid, limb length. © 2012 Elsevier Inc. All rights reserved. Current rates of total hip arthroplasty (THA) are on the rise with demand expected to burgeon by 174% by 2030 [1]. Efficient methods with which to improve compo- nent positioning will become increasingly important to maximize both productivity and patient outcomes for the joint surgeon and the increasing number of general orthopedists that will be required to meet this demand. Patient satisfaction, survivorship, and stability are all dependent on proper acetabular component positioning, limb-length equalization, and restoration of hip offset. Malpositioned acetabular components can result in increased dislocation rate, impingement, limited range of motion, increased osteolysis, increased polyethylene wear, and increased acetabular component migration [2-4]. Limb-length discrepancy after THA has been associated with nerve palsy, low back pain, abnormal gait, increased oxygen consumption and heart rate, and litigation [5, 6]. Failure to restore femoral offset has been tied to worsened gait and abductor function and increased component wear rates [7-10]. Current methods for intraoperative evaluation of component position, limb length, and offset include imaging with plain radiographs and fluoroscopy, the use of intraoperative mechanical devices, the use of ana- tomical landmarks, and computer navigation [2,11-14]. The anterior supine approach greatly simplifies the use of intraoperative fluoroscopy. However, although fluo- roscopy is beneficial when compared with radiographs in that it provides real-time imaging, the field of view is too narrow to easily compare the operative hip with the contralateral side. The purpose of our study was to evaluate an intraoperative fluoroscopic technique involving the use of a novel radiopaque grid in anterior supine THA. We hypothesized that the use of the grid would decrease component position variability including cup abduction, limb-length equalization, and restoration of hip offset when compared with the use of fluoroscopy alone. In addition, we hypothesized that the use of the fluoro- scopic grid would also decrease operative time when compared with fluoroscopy alone. Patients and Methods We retrospectively reviewed 99 consecutive primary THAs in 86 patients performed by a single surgeon (EK) through an anterior supine approach on a fracture table (PROfx; Mizuho OSI, Union City, Calif). All THAs were From the University of Utah, Department of Orthopaedic Surgery, Salt Lake City, Utah. Submitted August 16, 2011; accepted March 15, 2012. The Conflict of Interest statement associated with this article can be found at doi:10.1016/j.arth.2012.03.027. Reprint requests. Jeremy M. Gililland, MD, Department of Orthopaedic Surgery, University of Utah School of Medicine, 590 Wakara Way Salt Lake City, Utah 84108. © 2012 Elsevier Inc. All rights reserved. 0883-5403/0000-0000$36.00/0 doi:10.1016/j.arth.2012.03.027 1 The Journal of Arthroplasty Vol. 00 No. 0 2012