IBBC (interfacial bioactive bone cement method, Oonishi) (1) is an excellent technique for augmenting cement-bone fixation in the long term. However, the technique is difficult and there are concerns over some points, such as bleeding control, disturbance of cement intrusion to anchoring holes by granules, difficulty of the uniform granular dispersion to the acetabular bone (Zone 1 in particular). To improve this technique, we have modified IBBC (M-IBBC), and investigated the short-term clinical results and radiographic changes. K-MAX HS-3 THA (Kyocera Medical, Japan), with cemented stem and all polyethylene cemented socket, was used for THA implants. Basically the third generation cementing technique was used for THA using bone cement. The socket fixation was performed with bone cement (Endurance, DePuy) and hydroxyapatite (HA) granules (Ca10(PO4)6(OH)2, Boneceram P; G-2, Olympus, Japan). In original IBBC technique, HA granules were dispersed on reamed acetabulum before cementing. In M-IBBC technique, HA granules were attached to bone cement on plastic plate, then inserted to reamed acetabulum and pressurized. HA granules (G-2) are 0.3–0.6mm in size, with 35–38% porosity and sintered at 1150Introduction
Materials and Methods
We reviewed retrospectively the MRI examinations of 108 knees of 80 children to identify the prevalence of a high signal in the menisci of those without symptoms. There were 51 boys and 29 girls with a mean age of 12.2 years (8 to 15). The prevalence of a high signal within the menisci was 66%, significantly higher than that in an adult group (29%). The prevalence decreased with age: grade-2 and grade-3 changes were observed in 80% of menisci at ten years of age, in 65% at 13 years and in 35% at 15 years. The prevalence of high signals also decreased with increased skeletal maturity at the knee. We emphasise the importance of awareness of the high prevalence of a high signal intensity in the menisci of children, especially in early adolescence.
