Toshiyuki Kawai

Osteonecrosis of the femoral head (ONFH) is a debilitating disease that results in progressive collapse of the femoral head and subsequent degenerative arthritis. Few treatments provide both sufficient mechanical support and biological cues for regeneration of bone and vascularity when the femoral head is still round and therefore salvageable. We designed and 3D printed a functionally graded scaffold (FGS) made of polycaprolactone (PCL) and β-tricalcium phosphate (β-TCP) with spatially controlle

Samples of porous Ti metal were subjected to different acid and heat treatments. Ectopic bone formation on specimens embedded in dog muscle was compared with the surface characteristics of the specimen. Treatment of the specimens by H2SO4/HCl and heating at 600 °C produced micrometer-scale roughness with surface layers composed of rutile phase of titanium dioxide. The acid- and heat-treated specimens induced ectopic bone formation within 6 months of implantation. A specimen treated using NaOH fo

Although we encountered four complications, including three trochanteric problems, our findings suggest that THA without subtrochanteric shortening osteotomy can provide satisfactory long-term results in patients with Crowe IV hip.

Level III. See Instructions for Authors for a complete description of levels of evidence.

Patient-reported outcome measures (PROMs) are used to assess satisfaction after total hip arthroplasty (THA); however, the factors that determine these PROMs remain unclear. This study aimed to identify the patient- and surgery-related factors that affect patient satisfaction after THA as indicated by the Oxford Hip Score (OHS). One-hundred-and-twenty patients who underwent primary THA were included. Various patient-related factors, including clinical scores, and surgery-related factors were exa

In this study, we investigated the effect of different surface treatments (hydroxyapatite (HA) coating, alkali heat treatment, and no treatment) on the ability of bone to bond to a rough arc-sprayed Ti metal surface, using rabbit models. The bone-to-implant contacts for untreated, HA-coated, and alkali heat-treated implants were 21.2%, 72.1%, and 33.8% at 4 weeks, 21.8%, 70.9%, and 30.0% at 8 weeks, and 16.3%, 70.2%, and 29.9% at 16 weeks, respectively (n = 8). HA -coated implants showed signifi

This study was performed to investigate the relationship between patients' activity and function levels and the incidence of preoperative deep venous thrombosis (DVT) prior to total hip arthroplasty (THA). We retrospectively reviewed 500 patients admitted for primary or revision THA from July 2014 to October 2018. The diagnosis of DVT was confirmed using Doppler ultrasonography 1 month before THA. The patients' activity and hip function were evaluated using several clinical scores: the Harris Hi

THA with subtrochanteric transverse osteotomy provides satisfactory long-term results for Crowe type IV hips. For shorter required femoral resection lengths, the risk of delayed union was higher. A longer resection could permit fabrication of longer autologous longitudinal bone struts and likely contributes to enhanced stability at the osteotomy site.