Preliminary results from a multicentre prospective densitometric study on 89 patients (91 hips) that underwent primary THA with a DELTA-TT cup reported a postoperative recovery of bone mineral density in DeLee and Charnley zones starting from 12 and 24 months after surgery. Radiographic assessment confirmed the optimal osseointegration and therefore the stability of the acetabular cups¹. Already at 12 months, x-rays showed all the most sensitive signs that are reported to be indicative of bone in-growth²: the absence of radiolucent lines, the presence of a supero-lateral dense bone buttress at the bone-cup interface, the presence of medial stress-shielding in DeLee and Charnley zone II, the presence of radial trabeculae oriented in a direction perpendicular to the cup surface in DeLee and Charnley Zone I or Zone II and the presence of an infero-medial bone buttress (Figure 1).
Relevant clinical outcomes have been reported: the average Harris Hip Score and range of motion significantly improved from preoperative evaluation to 24 months. A subjective evaluation of the general health status by SF-36 revealed a significant improvement in patients’ quality of life with values higher than normalized ones for all scales already at 12 months¹. The early improvement in clinical and functional recovery after THA with DELTA-TT cup has also been proven by clinical study performed on 150 patients with an average follow-up of 12 months³.