The Journal of Arthroplasty Vol. 13 No. 1 1998
Brief Communication
Comparison of Total Hip
and Knee Component Weights
William M. Mihalko, MD, PhD, Mary Bayers-Thering, MS,
and Kenneth A. Krackow, MD
Abstract: Weights of total hip and total knee components from 4 major orthopaedic
device manufacturers are compared. These data provide surgeons with information
that is not readily available and may serve as a reference for patient information or
possibly biomechanical studies in the future. Key words: hip, knee, arthroplasty,
prosthetic components, biomechanics.
The changes in total hip and knee component
design and materials have been complex and varied
since the 1980s. One aspect not reported in the
design, manufacturing, and sales of these arthro-
plasty components is their weight and any differ-
ence in weight compared with the bone that is
resected. It has also been noted over the past several
years by the senior author (K.A.K.) that many
patients ask what their new joint arthroplasty will
weigh. To date, no previous publication has dis-
cussed this question; as well, no information on the
component packaging or product insert is available.
This study surveyed 4 major orthopaedic device
manufacturers for comparison of total hip and knee
component weights. Seven different total hip sys-
tems and 5 different total knee systems were used
for statistics and compared with the weight of bone
resected in primary total hip and knee surgery.
These data provide surgeons with information that
From the State University of New York at Buffalo, and the Buffalo
General Hospital, Buffalo, New York.
Reprint requests: Kenneth A Krackow, MD, B2 Department of
Orthopaedics, Buflalo General Hospital, 100 High Street, Buffalo,
NY 14203.
Copyright © 1998 Churchill Livingstone.
0883-5403/1301-001655.00/0
is not readily available and may be of general
interest to them and their patients. In addition, this
is information that can be considered in future
biomechanical studies.
Four major orthopaedic total joint manufacturers
were surveyed (Howmedica, Rutherford, NJ; DePuy,
Warsaw, IN; Zimmer, Warsaw, IN; Joint Medical
Products, Johnson & Johnson, Raynham, MA).
They freely submitted the weights of medium-sized
components of 7 different total hip systems and 5
different total knee systems. The data were sorted
by individual components as well as total weight of
all components needed in total hip (femoral stem
acetabular shell and insert and femoral head) and
total knee (femoral and tibial component, tibial tray,
and patellar backing) implantations. The data were
separated for the hip systems by alloy used for the
femoral stem (cobalt-chrome vs titanium) also, and
all total knee systems were grouped for comparison
of bone weight resected.
The weight of the bone resected for 20 total hip
and 20 total knee arthroplasties was determined in
the operating room using a triple-beam balance. For
total hip patients, the femoral head and calcar were
weighed in the operating room after the neck/calcar
cut was made. The acetabular and femoral canal
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