We have developed a new drug delivery system using porous apatite-wollastonite glass ceramic (A-W GC) to treat osteomyelitis. A-W GC (porosity, 70% and 20% to 30%), or porous hydroxyapatite (HA) blocks (porosity 35% to 48%) used as controls, were soaked in mixtures of two antibiotics, isepamicin sulphate (ISP) and cefmetazole (CMZ) under high vacuum. We evaluated the release concentrations of the antibiotics from the blocks. The bactericidal concentration of ISP from A-W GC was maintained for more than 42 days, but that from HA decreased to below the detection limit after 28 days. The concentrations of CMZ from both materials were lower than those of ISP. An in vivo study using rabbit
Coating titanium alloy implants with titanium nitride (TiN) by the method of Powder Immersion Reaction Assisted Coating (PIRAC) produces a stable layer on their surface. We have examined the ability of the new TiN coating to undergo osseointegration. We implanted TiN-coated and uncoated Ti6Al4V alloy pins into the
1. Homografts of eighteen-day-old foetal
We designed an in vivo study to determine if the superimposition of a microtexture on the surface of sintered titanium beads affected the extent of bone ingrowth. Cylindrical titanium intramedullary implants were coated with titanium beads to form a porous finish using commercial sintering techniques. A control group of implants was left in the as-sintered condition. The test group was etched in a boiling acidic solution to create an irregular surface over the entire porous coating. Six experimental dogs underwent simultaneous bilateral femoral intramedullary implantation of a control implant and an acid etched implant. At 12 weeks, the implants were harvested in situ and the
Surgeons and most engineers believe that bone compaction improves implant primary stability without causing undue damage to the bone itself. In this study, we developed a murine distal femoral implant model and tested this dogma. Each mouse received two femoral implants, one placed into a site prepared by drilling and the other into the contralateral site prepared by drilling followed by stepwise condensation.Aims
Methods
The torsion of both
An experimental study is reported of fracture healing in the
Puppies in the second half of their growing period have been observed for one and a half to four and a half months after creation of a superficial femoral arteriovenous fistula on the right side. From measurements of the whole bone and from microradiographic and tetracycline-fluorophore studies of the diaphysial bone, it is believed that the following statistically significant phenomena may be attributed to the influence of the arteriovenous fistula. 1. All bones distal to the fistula are influenced in their growth. The tibia and metatarsals become heavier and larger, but retain normal shape. Although stimulation of longitudinal growth is small, it is significant for the tibiae and nearly significant for the
1. Penetrating defects were cut in the
The intermittent administration of parathyroid hormone (PTH) increases the formation of bone by stimulating osteoblastic activity. Our study evaluates the possibility that intermittent treatment with PTH (1-34) may also enhance the implant-bone fixation of stainless-steel screws. Twenty-eight rats received one screw in either one (n = 8) or in both (n = 20) proximal tibiae. We administered either PTH (1-34) in a dosage of 60 μg/kg/day (n = 14) or vehicle (n = 14) over a period of four weeks. At the end of this time, the degree of fixation was assessed by measuring the removal torque on one screw in each rat (n = 28) and the pull-out strength on the contralateral screw (n = 20). PTH increased the mean removal torque from 1.1 to 3.5 Ncm (p = 0.001) and the mean pull-out strength from 66 to 145 N (p = 0.002). No significant differences in body-weight or ash weight of the
We used a trochanteric slide osteotomy (TSO) in 94 consecutive revision total hip arthroplasties (90 with replacement of both the cup and stem). This technique proved to be adequate for removing the components, with few complications (two minor fractures), and for implanting acetabular allografts (18%) and reinforcement devices (23%). Trochanteric union was obtained in most patients (96%), even in those with septic loosening (18/19), major femoral osteolysis (32/32), or previous trochanteric osteotomy (17/18). TSO is versatile, since it can be extended by a femoral flap (four cases) or a distal femoral window (eight cases). Despite significant bone loss, in 24% of the
The long-term effect of stainless steel and titanium alloy plates on structural remodelling and bone mass of osteotomised canine
There is little information about the effects of extracorporeal shock-wave about application the effects (ESWA) of on normal bone physiology. We have therefore investigated the effects of ESWA on intact distal rabbit
We studied 16
Insufficient protein ingestion may affect muscle and bone mass, increasing the risk of osteoporotic fractures in the elderly, and especially in postmenopausal women. We evaluated how a low-protein diet affects bone parameters under gonadal hormone deficiency and the improvement led by hormone replacement therapy (HRT) with 17β-oestradiol. Female Wistar rats were divided into control (C), ovariectomized (OVX), and 17β-oestradiol-treated ovariectomized (OVX-HRT) groups, which were fed a control or an isocaloric low-protein diet (LP; 6.6% protein; seven animals per group). Morphometric, serum, and body composition parameters were assessed, as well as bone parameters, mechanical resistance, and mineralogy.Objectives
Methods
We have tested the axial and torsional stability of femoral components after revision arthroplasty in a cadaver model, using impacted morsellised cancellous graft and cement. Each one of six matched pairs of fresh frozen human
We studied the biomechanical behaviour of three sliding fixation devices for trochanteric femoral fractures. These were a titanium alloy sideplate and lag screw, a titanium alloy sideplate and dome plunger with cement augmentation, and a stainless-steel sideplate and lag screw. We used 18 mildly osteoporotic cadaver
We have reviewed our experience of four iatrogenic femoral neck fractures in 315 consecutive closed intramedullary nailings with the AO/ASIF universal femoral nail. The average neck-shaft angle in the bones that fractured was 139.3 degrees +/- 1.2 degrees SD (136 to 141); in the whole series the average neck-shaft angle was 125.3 degrees +/- 8.6 degrees and only 11 had angles of more than 135 degrees. The upper ends of the nails in the four which fractured were 17 mm, 5 mm, 3 mm, and 1 mm below the tip of the greater trochanter. In the seven patients with neck-shaft angles greater than 135 degrees but with no fracture, none of the nails had been inserted beyond the tip of the greater trochanter. We nailed six cadaver
1. Cell differentiation around screws manufactured by two American and two Swiss companies and inserted into seventy