TITLE:
Natural Postoperative Bone Metabolic Changes after Total Knee Arthroplasty Determined by Positron Emission Tomography Scans
AUTHORS:
Masakazu Kanetaka, Soichiro Kaneko, Kei Wagatsuma, Kenji Ishii, Kimiteru Ito, Shinya Nakamura, Hiroshi Hamaji, Yukimasa Yamato, Yorito Anamizu, Fumiaki Tokimura, Tsuyoshi Miyazaki
KEYWORDS:
NaF, PET, Bone Metabolism, Total Knee Arthroplasty, Ischial Tuberosity
JOURNAL NAME:
Open Journal of Orthopedics,
Vol.8 No.12,
December
10,
2018
ABSTRACT: Artificial
joint replacement surgery is the orthopedic procedure of choice to relieve
pain, correct joint deformities, and help patients resume everyday activities.
However, the detailed mechanisms regulating peri-implant bone remodeling at the
bone-prosthesis
interface remain elusive. To address this gap in knowledge, we evaluated the
natural postoperative course of bone metabolism by using [18F] NaF
positron emission tomography (PET)/computed tomography in 57 patients (104
joints) who underwent asymptomatic total knee arthroplasty (TKA). First, we
measured total tracer uptake around TKA to determine the total bone metabolism
(TBM) and used the ischial tuberosity as the reference tissue for normalization
of PET images. Second, we calculated the TBM ratio (TBMR) by dividing the TBM
by tracer uptake in the reference tissue. A moderate increase in TBMR was observed
4 - 5 days
after implantation, and its intensity reached the maximum on the seventh
postoperative day. The TBMR showed no differences until 12 weeks, after which it decreased slowly
and returned to the basal levels. The new parameter TBMR and the unique pattern
of postoperative metabolic changes in the bone around the prosthesis may help
set accurate interpretation criteria to diagnose complications such as
loosening or infections.