Abstract
Aim: To determine if bonewax will act as a suitable barrier during cementation of bone cavities after curettage of bone tumours.
Method: One mix of methylmethacrylate cement was placed on top of a standard piece of bonewax. A steel thermometer probe was used to measure the temperature of the surface of the cement. The temperature was measured above and below the bonewax.
Results: The surface temperature of the cement was found to be 57°C both above and below the bonewax. The exothermic reaction occurred after the end of the cement working time, thus the bonewax acted as a physical barrier to protrusion of cement before melting away.
Discussion: Bone tumours such as GCT may cause cortical destruction. Standard treatment for many such benign tumours is curettage and cementation1. This is simplest when there is no cortical defect, other than the cortical window which is created by the surgeon who then curettes the tumour and performs any adjuvant therapy that is indicated. The cavity is then filled with cement, which is applied while still workable and runny to allow complete fill of the cavity. Pressurisation is the norm to interdigitate cement into bone to produce thermal necrosis of residual tumour cells. Problems occur when a cortical defect exists as this will allow the escape of cement into the joint or soft tissues with a detrimental thermal effect on cartilage or soft tissues2,3. The surface temperature found in this study is consistent with others4. A cortical defect will deny effective pressurisation, interdigitation and thermal necrosis of tumour cells. We have used bonewax in such surgery and found it is an effective barrier to cement protrusion during cementation of an incomplete cavity and allows effective pressurisation and interdigitation of cement whilst preventing potentially harmful escape of cement and direct contact with cartilage or soft tissues and thus reduces the risk of immediate thermal necrosis and of later third body joint wear1, or soft tissue irritation. Furthermore the bonewax disappears and is non-toxic.
Correspondence should be addressed to BOOS at the Royal College of Surgeons, 35 - 43 Lincoln’s Inn Fields, London WC2A 3PN
References:
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