Aim of this monocentric, prospective study was to evaluate the safety, efficacy, clinical and radiographical results at 24-month follow-up (N = 6 patients) undergoing hip revision surgery with severe acetabular bone defects (Paprosky 2C-3A-3B) using a combination of a novel phase-pure betatricalciumphosphate - collagen 3D matrix with allograft bone chips. Prospective follow-up of 6 consecutive patients, who underwent revision surgery of the acetabular component in presence of massive bone defects between April 2018 and July 2019. Indications for revision included mechanical loosening in 4 cases and history of hip infection in 2 cases. Acetabular deficiencies were evaluated radiographically and CT and classified according to the Paprosky classification. Initial diagnosis of the patients included osteoarthritis (N = 4), a traumatic fracture and a congenital hip dislocation. 5 patients underwent first revision surgery, 1 patient underwent a second revision surgery.Aim
Method
We evaluated the osteogenic potential of a novel biomimetic bone paste (DBSint®), made of a combination of a human demineralized bone matrix (hDBM) and a nano-structured magnesium-enriched hydroxyapatite (Mg-HA), in a standardized clinical model of high tibial osteotomy for genu varus. A prospective, randomized, controlled study was performed and thirty patients were enrolled and assigned to three groups: DBSint® (Group I), nano-structured Mg-HA (SINTlife®) (Group II) and lyophilized-bone-chips (Group III). Six weeks after surgery, computed tomography-guided biopsies of the grafts were performed. Clinical/radiographic evaluation was performed at six weeks, twelve weeks, six months, one and 2 year after surgery, in order to verify if the graft type influenced the healing rate.Introduction
Methods
Since July 2008 we are experimenting a new cup with iliac screw fixation, developed on the idea of Ring and Mc Minn. Iliac fixation is permitted by a polar screw of large diameter, coated by HA, which allows a compression to bone and a firm primary stability. Moreover it's possible to increase primary stability with further smaller peripherals screws. We present this new cup and report the preliminary results. Since July 2008 to April 2010, 51 cups were implanted. The diagnosis was aseptic loosening in 36 cases, septic loosening treated by two-stage revision in 7, hip congenital dislocation in 5, one case of post-traumatic osteoarthritis, one case of instability due to cup malposition and a case was an outcome of Girdlestone resection arthroplasty. Mean age was of 66 years (31-90).INTRODUCTION
MATERIALS AND METHOD
The use of monoblock tapered stems has shown very good results in hip revision surgery, particularly in case of severe proximal femur bone deficiency. However a too valgus neck, a short offset, may result in a high risk of dislocation. In addiction monoblock stems make the control of limb length difficult, and potentially increase the risk of subsidence or intraoperative fracture. Different types of modular tapered stems with distal fixation have been developed to allow a more user-friendly restoration of limb-lenght discrepancy and an indipendent proximal control of offset and anti-retroversion. We assessed 64 hip revisions performed on 63 patients (mean age 62 years). Indication for treatment was: aseptic loosening (42 cases) septic loosening (18 cases) and periprosthetic fracture (4 cases). According to Paprosky classification, femoral defects were staged as type I (2 cases), type II (20 cases), type IIIA (25 cases) and type IIIB (13 cases); periprosthetic fractures were all type B2 according to the Vancouver classification. In all cases we used a Restoration® Modular (Striker, Orthopaedics) cone-conical uncemented stem implanted by a lateral approach, with a trans-femoral osteotomy in 19 cases. A preventive cerclage cable was used in 10 patients in case of very thin cortex. We used the minimum size stem in most of the cases. Mean follow-up was 20 months (range 6–36). Short-term complications included hip dislocation (1 case), recurrent infection (1 case), stem subsidence >
5 mm (1 case). Mean Harris Hip Score improved from 43 to 81.9 (t test p<
0.0005), while limb lenght discrepancy improved in 97% of cases with symmetry in 76%. The use of modular revision stems is an effective alternative in hip revision surgery that ensures good primary stability, while modularity enables the implant to be tailored to the patient, allowing restoration of the limb length and correct muscular balancing.
