DOS BULLETIN - Dansk Ortopædisk Selskab

2010-378_DOS nr. 3 2010 29/09/10 10:08 Side 78
In-vivo temperature profile at cement-bone interface
during cementation of preheated femoral component
Juozas Petruskevicius, Mogens Berg Laursen,
Mogens Brouw Jørgensen, Kjeld Søballe, Poul Torben Nielsen
Orthopedic Division, Northern Denmark Region, Aalborg Hospital,
University of Aarhus; Department of Orthopaedics,
University Hospital of Aarhus
Background: The heat generation during cement polymerization might
have a negative effect on bone tissue. Developing new methods of
cementation technique such as preheating of femoral stem has renewed
the discussion of whether the cement curing temperature could induce
thermal osteonecrosis at cement-bone interface (CBI). Conventionally, a
cold femoral stem acts as the heat sinker, while the preheating of the
prosthesis above room temperature could increase the heat generation
and damage the bone cells.
Purpose: The aim of this study was to record a temperature profile at
CBI, when cementing preheated (40° C) and non- preheated femoral
components during total hip arthroplasty (THA).
Methods: Eighty patients were randomly allocated to one of the 2
groups with 40 in each. Peroperative temperature measurements at CBI
were performed using sterile copper-constantan thermocouples at posterior
femur at the level of lesser trochanter.
Findings: A mean peak temperature reached 53.8 and 56.4° C (p = 0.32)
when cementing non-preheated and preheated stems, respectively. However,
a time interval from cement mixing to peak temperature and correspondingly
cement polymerization time was significantly shorter (40
sec, p = 0.0003) in the preheated stem group. The median exposure time
with temperatures above 50° C at CBI was 70 sec. in both groups (range:
0-200 and 0-190 for preheated stem and control group, respectively).
Conclusion: High cement curing temperatures at CBI in both groups
could indicate a large cement mass due to a good cement penetration at
the site of the temperature recordings. Preheating of stem to 40° C had a
little effect on heat generation at CBI, but had significantly reduced
cement polymerization which could be beneficial to shortening the operating
time.
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