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Arthroplasty 2019
June 24-25, 2019
Volume 14
Journal of Orthopaedics Trauma Surgery and Related Research
Arthroplasty
June 24-25, 2019 | Rome, Italy
12
th
International Conference on
Mid-term outcomes and evaluation following implantation with a recalled modular neck femoral stem
Daniel Li
Northwestern University, USA
N
eck-stem corrosion has been associated with Adverse Local Tissue Reaction (ALTR) in dual-taper femoral stems.
In this study, we examine a single surgeon’s retrospective case series of 42 hips in 38 patients who underwent
primary total hip arthroplasty (THA) with a dual-taper femoral component. Evaluation consists of clinical exam, labs
including metal ion levels, and MARS MRI. We propose that hip aspiration would be a beneficial adjunct. Each hip
aspirate was classified into Class 1, 2, or 3, based on qualitative variables. 19/42 hips were symptomatic, 38/42 had
elevated Cobalt, and 23/42 had abnormal MRI findings. 40% of aspirates were Class I (benign), 17% Class 2, and
43% Class 3. Class 2 and 3 aspirates are associated with abnormal MRI Mid-term Outcomes and Evaluation Following
Implantation with a Recalled Modular Neck Femoral Stem, elevated Cobalt, and a high rate of revision (71% and 72%,
respectively). A small subset of patients (2/38) with symptoms, normal labs and MRI, had abnormal aspirates with
extensive tissue necrosis at revision. A significant proportion of the aspirates were unable to complete a cell count due to
cellular degradation or degeneration, or inability to process a thick fluid sample. For those samples that were processed,
cells counts were variable in terms of the differential of neutrophils, lymphocytes, and monocytes. We noted a much
higher percentage of patients with elevated Cobalt levels (90%) versus Chromium (22%), which appears to be consistent
with contemporary literature. The utility of this diagnostic test may be apparent when looking more closely at select
patients. Within the patients who have been revised, there were 2 patients who were symptomatic, yet had normal cobalt
and chromium labs, as well as a normal MARS MRI, yet had Class 3 aspirates, and were noted to have moderate to
severe soft tissue necrosis at the time of revision surgery. These patients may potentially be overlooked for early revision.
J.Orthop.Trauma Surg.Relat.Res. | Volume 14
ISSN:2449-9145