Review Article Periprosthetic Fractures Around Loose Femoral Components Abstract Roshan P. Shah, MD, JD The development of periprosthetic fractures around loose femoral Neil P. Sheth, MD components can be a devastating event for patients who have undergone total hip arthroplasty (THA). As indications for THA expand Chancellor Gray, MD in an aging population and to use in younger patients, these fractures Hassan Alosh, MD are increasing in incidence. This review covers the epidemiology, risk Jonathan P. Garino, MD factors, prevention, and clinical management of periprosthetic femoral fractures. Treatment principles and reconstructive options are discussed, along with outcomes and complications. Femoral revision with a long-stem prosthesis or a modular tapered stem is the mainstay of treatment and has demonstrated good outcomes in the literature. Other reconstruction options are available, depending on bone From Columbia University, New York, quality. Surgeons must have a sound understanding of the diagnosis NY (Dr. Shah), the University of and treatment of periprosthetic femoral fractures. Pennsylvania, Philadelphia, PA (Dr. Sheth, Dr. Gray, and Dr. Alosh), and the Pennsylvania Orthopedic Center, Alvern, PA (Dr. Garino). otal hip arthroplasty (THA) The incidence of periprosthetic hip Dr. Shah or an immediate family Treliably treats hip pain caused by fractures is increasing. Bhattacharyya member has stock or stock options articular cartilage degeneration; et al5 found a 216% increase between held in Pfizer, Merck, GlaxoSmithKline, Alnylam, and Intuitive Surgical. however, the development of peri- 2002 and 2006. Several reasons for Dr. Sheth or an immediate family prosthetic femoral fractures after the increase have been proposed.1,2 member serves as a paid consultant to THA is a devastating complication. First, the total prevalence of patients Zimmer. Dr. Garino or an immediate Two registry studies form the foun- living with THA is increasing. Sec- family member has received royalties from Smith & Nephew; is a member of dation of our understanding of these ond, with time, the number of pa- aspeakers’ bureau or has made paid fractures. Between 1969 and 1999, tients experiencing osteolysis to presentations on behalf of Smith & 1,249 fractures out of 30,329 hip a varying degree, as well as compo- Nephew; serves as a paid consultant to arthroplasty cases were studied in the nent loosening, will increase. Third, Smith & Nephew and DePuy; has 1 received research or institutional Mayo Clinic Joint Registry. Peri- as patients age, there is a greater risk support from Zimmer; and serves as prosthetic fractures in the Swedish for the development of osteoporosis a board member, owner, officer, or National Hip Arthroplasty Registry and periprosthetic fracture caused committee member of the were studied retrospectively between by minor trauma. Fourth, with the Pennsylvania Orthopedic Society. 2 Neither of the following authors nor any 1979 and 1998 and prospectively success of THA and its expanding immediate family member has received between 1999 and 2000.3 The latter indications, more patients are young anything of value from or has stock or study found that femoral peri- and active; consequently, this patient stock options held in a commercial prosthetic fractures were the third population has a greater exposure to company or institution related directly or indirectly to the subject of this article: most frequently reported reason for higher energy trauma and therefore Dr. Gray and Dr. Alosh. reoperation after THA, accounting an increased risk of periprosthetic J Am Acad Orthop Surg 2014;22: for 9.5% of the revisions between fracture. Fifth, the expanding class of 482-490 1999 and 2000.3 Other studies have patients with THA logically leads to reported the prevalence of late peri- a greater number of patients requir- http://dx.doi.org/10.5435/ JAAOS-22-08-482 prosthetic hip fractures to be ing revision THA. between 0.1% and 18%,4 with an Several treatment options have Copyright 2014 by the American Academy of Orthopaedic Surgeons. annual incidence of between 0.045% been proposed based on an accurate and 0.13%.2 classification of the fracture type and 482 Journal of the American Academy of Orthopaedic Surgeons Copyright Ó the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited. Roshan P. Shah, MD, JD, et al implant stability. Preoperatively dif- technique, and the type of implant department after sustaining spon- ferentiating between a loose and used.9,10 Osteolysis and loosening are taneous or low-energy trauma and a stable femoral implant can be most directly related to Vancouver maybeseeninthetraumabayafter challenging, but certain signs and type B2 and B3 fractures. Routine sustaining high-energy trauma. symptoms can be helpful. Fractures clinical follow-up is necessary to Advanced Trauma Life Support occurring around loose implants identify patients at risk for loosening, guidelines should always be used for require femoral stem revision. and regular radiographic evaluations initial patient evaluation following have been shown to be cost effec- trauma. Conducting an appropriate tive.11 Biomechanical studies have physical examination will help Vancouver Classification demonstrated that loose femoral reveal associated musculoskeletal stems have a nearly 60% reduction in injuries. A thorough history pro- The Vancouver classification is the the torque to failure compared with vides information about the medical most common classification system well-fixed stems.12 In a study by Beals causes of spontaneous or low-energy used to describe periprosthetic frac- and Tower,13 27% of patients with injury, such as syncope, cardiopul- tures. This classification is based on fractures had evidence of loosening monary compromise, or stroke; any fracture location, implant stability, preoperatively. The Swedish registry underlying disorders should then be and integrity of the residual bone showed that 70% of fractures managed by the appropriate spe- stock.6,7 Type B fractures occur along involved loose prostheses, with 23% cialist. As with any femur fracture, the length of the femoral stem. Type B known to be loose and 47% first significant blood loss may occur, fractures are further subdivided by identified as loose at the time of sur- requiring close monitoring of car- stem stability and bone stock. Type gery.2 It is unclear what contribution diopulmonary vital signs and vol- B1 fractures are fractures with a sta- infection has to loosening and sub- ume status. Medical co-management ble femoral component. Type B2 sequent fracture. The inflammatory is the most effective method by fractures are fractures with a loose markers erythrocyte sedimentation which to optimize care of patients femoral component but with sup- rate and C-reactive protein have poor with periprosthetic fractures before portive femoral bone stock. Type B3 specificity in the setting of a frac- surgical intervention. fractures are fractures with a loose ture.14,15 However, intraoperative Previous surgical notes should be femoral component and associated aspiration for cell count and culture obtained, especially if the index pro- poor integrity bone stock, wherein studies provides valuable information cedure was performed at an outside the metaphyseal and diaphyseal bone when the suspicion for infection is institution, to properly identify the stock is deficient and unsupportive. high. We use standard cut-off values currently implanted devices. If prior The incidence and prevalence of each of 3,000 WBC/mLand80%poly- records are unavailable, consultation Vancouver type are not well known, morphonuclear cells for diagnosing with other surgeons and industry rep- for the same reasons that make the true infection. Because of fracture bleed- resentatives can help determine the incidence of all periprosthetic fractures ing, we correct for the contribution of components and the manufacturers. elusive. In the Swedish registry report, serum white blood cells with the Finally, preoperative surgical planning 53% of the fractures were type B2 and following formula: is critical in achieving clinical success. only 4% were type B3.8 When the Arrange to have all extraction devices group examined whether the index 5 WBCcorrected WBCobserved and revision equipment available for surgery was a primary THA or a revi- ÂÀ 2 WBC · RBC = the implanted components. In addi- sion THA, they found that fractures serum fluid ÁÃ tion, a thorough and systematic eval- occurring after primary THA were RBC ;16 serum uation of the acetabular component more commonly type B2, whereas should be conducted intraoperatively fractures occurring after revision THA because an acetabular revision requir- were more commonly type B1.2 where WBC is white bloods cells and RBC is red blood cells. ing more than a liner exchange may be necessary (ie, loose component, poor Risk Factors component position, poor implant track record, shell or locking mecha- General risk factors for the develop- Management nism damage, extensive corrosion). ment of periprosthetic fractures after Radiographic studies consisting of THA include osteolysis and loosen- Preoperative Evaluation an AP pelvis and AP and cross-table ing, trauma, age, gender, osteoporo- Patients with periprosthetic fractures lateral views of the hip should sis, index diagnosis, revision surgery, generally present to the emergency be obtained to assess for fracture August 2014, Vol 22, No 8 483 Copyright Ó the American Academy of Orthopaedic