Trabecular TitaniumTM is a tri-dimensional material composed by multi-planar regular hexagonal cells and characterised by a highly open porosity that has been studied to optimise bone osteointegration. The aim of this study is to evaluate bone remodelling measuring BMD changes around an acetabular cup made from Trabecular TitaniumTM in primary total hip arthroplasty (THA).

Between February 2009 and December 2010, 89 patients (91 hip) underwent primary THA with a modular acetabular cup in Trabecular TitaniumTM (DELTA-TT cup, Limacorporate, Villanova di San Daniele, Italy). The average age was 63.5± 9.4 years, the average height and weight were 75.9± 12.9 kg and 168.8± 8.9 cm, respectively (av. BMI 26.8± 4.2). There were 46 (51.7%) males and 43 (48.3%) females affected by primary coxarthrosis in 80 (87.9%) cases, avascular necrosis in 5 (5.5%), posttraumatic coxarthrosis in 3 (3.3%), dysplasia in 2 (2.2) and oligoarthritis in 1 (1.1%) case. The study includes the clinical evaluation with Harris Hip Score (HHS) and SF-36, radiographic evaluation and dual-energy x-ray absorptiometry (DEXA) analysis preoperatively and postoperatively at 1 week, 3, 6, 12 and 24 months.

Preliminary results are currently available for 47 patients at 12 months, 68 at 6 months and 80 at 3 months. The average HHS significantly improved from 48.7± 14.99 preoperatively to 93.8± 5.91 at 12 months, with a constant progression in the intermediate follow-ups. All patients showed a significant ROM increase, with an average flexion from 86.6°± 15.9° preoperatively to 105°±13.14 at 12 months. Sf-36 highlighted a satisfactory improvement of general health status from an average preoperative value of 50.8± 18.7 to 80.7± 12.9 at 12 months (from 42.9 to 80.1 for physical health; from 58.4 to 81.3 for mental one). All cups were stable at 12 months with no radiolucent lines. Preliminary DXA analysis reported an initial bone mineral density decrease from 1 week baseline values (BMD R1: 1.40± 0.37; R2: 1.20± 0.45; R3:1.16± 0.31) to 3 months (BMD R1: 1.31± 0.41; R2: 1.17± 0.3; R3: 1.06± 0.37) followed by BMD recovery up to initial values (BMD R1: 1.37± 0.3; R2:1.18± 0.34; R3: 1.12± 0.36) at 12 months.

Trabecular TitaniumTM demonstrates a good primary and secondary stability. Preliminary densitometric outcome confirms an optimal osseointegration of the DELTA-TT cup and early clinical and patient subjective results are very promising at a short term follow-up. However, the completions of follow-up evaluation are necessary to draw a conclusive analysis.