Outcomes of combined hip procedure with dual mobility cup versus osteosynthesis for acetabular fractures in elderly patients: a retrospective observational cohort study of fifty one patients

International Orthopaedics https://doi.org/10.1007/s00264-020-04757-w ORIGINAL PAPER Outcomes of combined hip procedure with dual mobility cup versus osteosynthesis for acetabular fractures in elderly patients: a retrospective observational cohort study of fifty one patients Xavier Lannes 1 & Kevin Moerenhout 1 & Hong Phuoc Duong 2 & Olivier Borens 1 & Sylvain Steinmetz 1 Received: 4 April 2020 / Accepted: 27 July 2020 # The Author(s) 2020 Abstract Purposes Acetabular fractures are more and more common in the elderly. Open reduction and internal fixation (ORIF) may lead to poor outcomes and high revision rates. Primary total hip arthroplasty (THA) combined with internal fixation, also known as the combined hip procedure (CHP), associated with dual mobility cup (DM-CHP) could be an efficient procedure in selected elderly patients. The aim of this study is to compare functional and radiological outcomes between ORIF and DM-CHP. Methods Between 2007 and 2018, 51 patients older than 65 years were surgically treated for acetabular fractures. Twenty-six patients were treated by DM-CHP and 25 by ORIF. Each group was divided into two subgroups regarding a single or combined approach. Hospital stay, surgical time, intraoperative blood loss, and complications were documented. The Harris Hip Score (HHS) was used for measuring the functional outcome. Radiological analysis was used to assess the centre of rotation in the DMCHP group. Results Median surgery time and intra-operative blood loss were higher in DM-CHP than those in ORIF. Early medical complication rate was higher for a combined approach as compared with a single posterior approach in DM-CHP (p = 0.003). Dislocation rate was 7.7% in DM-CHP. Revision rate was higher in ORIF (20% versus 7.7%). HHS was similar in both groups. Conclusions DM-CHP leads to similar functional outcomes and less revision than ORIF. This study strengthens the practice of using only the posterior approach for primary THA in the elderly. Dual mobility is a valid therapeutic option for acetabular fractures in elderly patients. Keywords Combined hip procedure . Open reduction internal fixation . Dual mobility cup . Acetabular fractures . Center of rotation . Elderly patient * Sylvain Steinmetz Xavier Lannes Kevin Moerenhout Hong Phuoc Duong Olivier Borens 1 Department of Orthopaedic Surgery and Traumatology, Centre Hospitalier Universitaire Vaudois (CHUV), Rue du Bugnon 46, 1011 Lausanne, Switzerland 2 Institute for Research in Rehabilitation, Clinique romande de réadaptation Sion, Avenue du Grand-Champsec 90, 1950 Sion, Switzerland Introduction Acetabular fractures in patients aged 60 years and older have steadily become more frequent with a report of a 2.4-fold increase in incidence [1]. Kannus et al. [2] have also shown a rise of 23% of osteoporotic pelvic fractures with an ever older population. Low-energy trauma (LE) accounts for more than 50% of elderly acetabular fractures [3], which normally lead to a “senior fracture pattern”. This pattern consists of a displaced anterior column fracture associated with a posterior column fragment with a large portion of the quadrilateral surface displaced medially and cranially [1]. Some studies have shown that there are predictable factors of poor outcome concerning open reduction and internal fixation (ORIF), namely, age and non-anatomical reduction [4], superior anteromedial dome impaction [5], involvement of the International Orthopaedics (SICOT) posterior wall with marginal impaction or comminution [6], and femoral head damage [7]. About 17% of the patients [8] will need secondary total hip arthroplasty (THA) after acetabular fracture treated by ORIF. This surgery can be technically difficult and lead to high complication rates [9]. ORIF associated with primary THA, also known as the “ combined hip procedure” (CHP), seems to be an attractive procedure with satisfactory results in selected patients [10–13] and lead to equivalent non-fatal complication rate as ORIF [8]. Compared with ORIF, there is no need for an anatomic reduction, but there must be an adequate stability and bone stock to achieve THA. This surgical procedure allows for early mobilization with total weight-bearing [12], which should theoretically lead to fewer post-operative complications [14]. Dislocation rate in acetabular fractures treated by acute THA can run up to 23% [11, 15]. Dual mobility cups (DMC) are associated with lower rates of dislocation in primary surgery [16], revision surgery [17], and in primary THA for femoral neck fractures [18]. DMC could therefore be a useful tool for acetabular fractures. Our hypothesis is that dual mobility-combined hip procedure (DM-CHP) is a safe procedure, with comparable clinical results and less early revision rate than ORIF in selected patients older than 65 years treated for acetabular fractures. The aim of this study is to compare the functional and radiological outcomes between DM-CHP versus ORIF in consecutive patients older than 65 years treated for acetabular fractures. Patients and methods Patients We retrospectively reviewed in our level I trauma department consecutively patients older than 65 years with acetabular fracture on a native hip who were treated surgically with ORIF or DM-CHP from January 2007 to September 2018. Patients were divided into two groups based on two surgical methods: ORIF and DM-CHP. The indications for DMCHP were severe comminuted articular fractures and marginal impaction (especially in weight-bearing area), fracture displacement of more than 20 mm, concomitant femoral head or neck fracture, marked osteoporosis (Singh index ≤ 2), and pre-existing symptomatic hip degenerative joint disease. ORIF group was divided into two subgroups: operated by a single approach (SA-ORIF) (anterior or posterior) and operated by a combined approach (CA-ORIF) (anterior and posterior). DM-CHP was subdivided in a single approach (SA-CHP) and combined approach (CA-CHP). Surgical procedure Surgery was done by two of our senior lower limb trauma surgeons. For the ORIF group, the surgical approach was decided depending on the fracture pattern [19]. When the anterior column was involved, a modified Stoppa approach was realized. For posterior column or posterior wall fractures, the Kocher-Langenbeck approach was performed. Finally, in both column fractures, anterior followed by posterior approaches were used. Osteosynthesis was realized with a suprapectineal quadrilateral buttress plate (PRO Quadrilateral surface plates, Stryker®, Kalamazoo, MC, USA) when anterior column was involved and by a reconstruction plate (Matta pelvic plates, Stryker®, Kalamazoo, MC, USA) or one-third tubular plate (DePuySynthes®, New Brunswick, NJ, USA) when posterior column or wall was involved. For four patients, the outer window of the ilioinguinal approach was used in combination with a modified Stoppa approach. In the DM-CHP group, osteosynthesis was done first, followed by the THA. W (...truncated)