The continual cycle of bone formation and resorption
is carried out by osteoblasts, osteocytes, and osteoclasts under
the direction of the bone-signaling pathway. In certain situations
the host cycle of bone repair is insufficient and requires the assistance
of bone grafts and their substitutes. The fundamental properties
of a bone graft are osteoconduction, osteoinduction, osteogenesis,
and structural support. Options for bone grafting include autogenous
and allograft bone and the various isolated or combined substitutes
of calcium sulphate, calcium phosphate, tricalcium phosphate, and
coralline hydroxyapatite. Not all bone grafts will have the same
properties. As a result, understanding the requirements of the clinical
situation and specific properties of the various types of bone grafts
is necessary to identify the ideal graft. We present a review of
the bone repair process and properties of bone grafts and their
substitutes to help guide the clinician in the decision making process. Cite this article:
Failure of fixation is a common problem in the treatment of osteoporotic fractures around the hip. The reinforcement of bone stock or of fixation of the implant may be a solution. Our study assesses the existing evidence for the use of bone substitutes in the management of these fractures in osteoporotic patients. Relevant publications were retrieved through Medline research and further scrutinised. Of 411 studies identified, 22 met the inclusion criteria, comprising 12 experimental and ten clinical reports. The clinical studies were evaluated with regard to their level of evidence. Only four were prospective and randomised. Polymethylmethacrylate and calcium-phosphate cements increased the primary stability of the implant-bone construct in all experimental and clinical studies, although there was considerable variation in the design of the studies. In randomised, controlled studies, augmentation of intracapsular fractures of the neck of the femur with calcium-phosphate cement was associated with poor long-term results. There was a lack of data on the long-term outcome for trochanteric fractures. Because there were only a few, randomised, controlled studies, there is currently poor evidence for the use of bone cement in the treatment of fractures of the hip.
