Kompendium 2020 Forschung & Klinik

TOP-Studien
58
Distal Femur Replacement –
Differences between Oncologic
and Non-Oncologic Conditions
[…] this study is of vital importance since
it is the first one to show the differences
between patients with and without
oncologic conditions undergoing DFR.
Cementation might be a better fixation
method for patients with oncologic
condition […]
Kevin Staats
Study:
Staats K, Vertesich K, Sigmund
IK, Sosa B, Kaider A, Funovics
PT, Windhager R. Does a
Competing Risk Analysis Show
Differences in the Cumulative
Incidence of Revision.
Clin Orthop Relat Res. 2020
May;478(5):1062–1073.
The use of megaprosthetic reconstruction of the extremities
originated from extended bone loss due to wide resection of
bone or soft-tissue tumors. However, due to the growing number
of primary total knee arthroplasty (TKA) and the expanding life
expectancy of patients, information about the outcome of distal
femur replacement (DFR) due to non-oncologic conditions in
revision-TKA (rTKA) is becoming more and more important.
We therefore raised the question, whether differences in patient
population and DFR fixation (cemented or cementless) have an
impact on the outcome after DFR.
In a retrospective cohort study, we analyzed patients undergoing DFR due
to oncologic and non-oncologic indications from 1986 to 2016. We were
able to include 229 patients, in total of which 183 patients underwent DFR
due to oncologic, and 46 patients due to non-oncologic conditions. Patients
undergoing DFR due to oncologic reasons were – as expected – significantly
younger than the cohort with non-oncologic conditions. Cementless fixation
was more often performed in oncologic cases, whereas in the non-oncologic
cohort cementation and cementless fixation were almost equally distributed.
Table 1 displays the basic demographics and differences between
patients with oncologic and non-oncologic reasons undergoing cemented
and cementless DFR. The decision whether patients received cemented or
cementless distal femoral replacements was not based on a strict algorithm.
We strongly believe the indications for cemented or cementless fixation have
not changed dramatically in our institution over time. Usually, cementless
fixation is preferred in young, active patients and in those with primary bone
tumors, whereas cemented fixation is mainly used in older patients with
expected poor bone quality or metastatic bone lesions. However, bone quality
and patient activity level were not assessed for the entire patient cohort.
Regardless of which distal femoral replacement system was used, it always
consisted of a cemented or cementless modular component fitting the metaphyseal
and diaphyseal portion of the distal femur.
Patients and Method
In our study, the 149 patients receiving cementless fixation were younger
(median age 31 years [range 16-55 years]) than the 80 patients with cemented
distal femoral replacement (median age: 54 years [range 27-72 years];