Uncemented fully hydroxyapatite-coated hip stem for intracapsular femoral neck fractures in osteoporotic elderly patients: a multicenter study.

Arthroplasty Today 1 (2015) 81e84 Contents lists available at ScienceDirect Arthroplasty Today journal homepage: http://www.arthroplastytoday.org/ Original research Uncemented fully hydroxyapatite-coated hip stem for intracapsular femoral neck fractures in osteoporotic elderly patients: a multicenter study Fabrizio Rivera, MD a, *, Francesco Leonardi, MD a, Pietro Maniscalco, MD b, Marco Caforio, MD b, Roberto Capelli, MD c, Giampaolo Molinari, MD c, Paolo Esopi, MD d a Orthopaedic Department, SS Annunziata Hospital, Savigliano (CN), Italy Trauma Department, Hospital of Piacenza, Piacenza, Italy Trauma Department, Azienda Ospedaliera Fatebenefratelli, Milano, Italy d Department of Trauma, Dolo Hospital, Dolo, Venice, Italy b c a r t i c l e i n f o a b s t r a c t Article history: Received 14 December 2014 Received in revised form 22 February 2015 Accepted 24 February 2015 Available online 28 August 2015 There is still debate over the limits of age and bone stock quality of patients on whom to use an uncemented straight stem coated with hydroxyapatite (HA). We studied a group of 244 patients with a displaced intracapsular fracture of the femoral neck who underwent cementless hemiarthroplasty or total hip arthroplasty. 143 patients were reviewed at the two-year follow up. A fully HA-coated stem for intracapsular hip fracture results in a satisfactory return to pre-injury mobility and a low complications rate. The advantage reported in the literature of a low mortality rate with use of an un-cemented implant in elderly patients was shown to be greater still on finding an immediate primary stability and rapid osteointegration of the implant. Copyright © 2015 Published by Elsevier Inc. on behalf of American Association of Hip and Knee Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/). Keywords: Uncemented stem Femoral neck fracture Hydroxyapatite Introduction The concept of full coating to fixate a prosthetic stem whose geometry affords a reduction in proximal-distal rigidity was introduced 25 years ago [1,2]. Despite good results documented in the literature however, the ideal type of coating and prosthetic design are still under discussion. The problem is even more evident if the host bone has osteoporotic characteristics. The critical issues are primary fixation and osteointegration. The stability of the primary fixation depends on the prosthesis design and coating material. Radiostereometric analysis (RSA) studies of stem migration have shown precocious and definitive stability of fully coated implants and better results compared to porous metalcoated implants of similar geometry [3,4]. Osteointegration is enabled by the interaction of the bone stock and the inert material coating of the prosthesis [5]. This phenomenon is not transitory but is seen throughout the entire duration of the arthroprosthesis in a process of periprosthetic remodeling. The quality of the bone is therefore vitally important for the short- and long-term survival of the implant. The use of an uncemented straight stem coated with hydroxyapatite (HA) in young, active patients with good bone quality is an indication endorsed in the literature [6e8]. There is still debate, on the other hand, over the limits of age and bone stock quality of patients on whom to use this type of prosthetic solution. In light of this, we studied a group of patients having intracapsular hip fractures treated with a collarless fully HA-coated stem as a prosthetic solution and analyzed their clinical and X-ray results over a 2-year follow-up. Material and methods No author associated with this paper has disclosed any potential or pertinent conflicts which may be perceived to have impending conflict with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.artd.2015.02.002. * Corresponding author. Via Servais 200 A16, 10142 Savigliano (CN), Torino, Italy. Tel.: þ39 3472992578. E-mail address: We retrospectively reviewed a group of 244 patients with a displaced intracapsular fracture of the femoral neck who underwent cementless hemiarthroplasty or total hip arthroplasty with a collarless fully HA-coated right stem. Our group of study consisted of all patients admitted with a diagnosis of intracapsular hip fracture between April 2011 and July 2012. The exclusion criteria for http://dx.doi.org/10.1016/j.artd.2015.02.002 2352-3441/Copyright © 2015 Published by Elsevier Inc. on behalf of American Association of Hip and Knee Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 82 F. Rivera et al. / Arthroplasty Today 1 (2015) 81e84 our study were: patients with arthritic changes involving the acetabulum and pathological fractures. Informed written consent from all patients was obtained prior to any intervention. Degree of Osteoporosis was evaluated measuring Cortical Thickness Index (CTI) according to Dorr [9]. CTI was assessed by examination of opposite femur on routine pelvis radiograph for preoperative planning. All surgical operations were done under spinal or epidural anesthesia at the discretion of the anesthetist. A lateral approach to the hip was used in 186 patients and a posterior approach was used in 58 patients, according to the surgeon's preference. Ultra short-term antibiotic prophylaxis was performed in all patients. Prophylaxis against heterotopic ossifications was done by administration of nonsteroidal anti-inflammatory drugs. All patients received a collarless fully HA-coated Korus stem (Gruppo Bioimpianti, Peschiera Borromeo, MI, Italy) (Fig. 1). The Korus stem, made of a titanium-substrate, has a triple-tapered design, being tapered in the anterior-posterior (AP) dimension and from lateral to medial. The stem features both horizontal and vertical grooves to increase both rotational and axial stability after implantation. Both the 135 and 125 CCD angle neck stems are coated with a layer of Osprovit hydroxyapatite (HA) of approximately 150 mm thickness. The combination of the macrostructure tapering, horizontal and vertical grooves and the HA coating was devised to promote implant stability. The Korus stem should be implanted with either a collarless or collared stem, depending on the surgeon's preference and estimations of bone quality. In 181 cases patients received a bipolar cup (Janus cup, Gruppo Bioimpianti, Peschiera Borromeo, MI, Italy), in 14 cases a traditional cup (Fin II cup, Gruppo Bioimpianti, Peschiera Borromeo, MI, Italy) (Figs. 2 and 3), and in 49 cases a dual mobility cup (Dualis cup, Gruppo Bioimpianti, Peschiera Borromeo, MI, Italy). Pre-operative indication of the use of coupling with a different type of acetabular component was as follows: a traditional cup in patients under 80 not showing co-morbidity with pre-fracture unaided walking; a bipolar cup for patients over 80 or in those under 80 but with low capacit (...truncated)