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Erschienen in: Clinical Orthopaedics and Related Research® 1/2014

01.01.2014 | Symposium: 2013 Knee Society Proceedings

Knee Moments After Unicompartmental Knee Arthroplasty During Stair Ascent

verfasst von: Yang-Chieh Fu, PhD, Kathy J. Simpson, PhD, Cathleen Brown, PhD, Tracy L. Kinsey, MSPH, Ormonde M. Mahoney, MD

Erschienen in: Clinical Orthopaedics and Related Research® | Ausgabe 1/2014

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Abstract

Background

For unicompartmental knee arthroplasty (UKA), abnormal loading on the tibiofemoral joint could exacerbate knee osteoarthritis or implant wear. Joint moments are an indirect measure of such loading. However, little is known about knee moments of patients with UKA, tempering enthusiasm for its use.

Questions/purposes

In patients with UKAs performing stair ascent, we (1) determined whether interlimb differences for knee moments are demonstrated, (2) described the knee kinetics of patients with medial and lateral UKAs, and (3) investigated possible factors that might influence the knee abductor moments.

Methods

In our cross-sectional study, we recruited 26 patients with UKA with nondiseased contralateral limbs who performed stair ascent. Seventeen patients had medial UKAs and nine had lateral UKAs. Paired t-tests and CIs were applied to determine interlimb differences within each UKA group for peak knee moments and times to peak moments.

Results

During stair ascent, the medial UKA group displayed greater peak extensor moments for the nondiseased compared to the UKA limb (p = 0.030), whereas the lateral UKA group did not (p = 0.087). For both medial and lateral UKA groups, the UKA limb demonstrated greater internal peak abductor moments (p = 0.005 and 0.013, respectively). Both UKA groups exhibited knee moments similar to those in the literature. Limb dominance and postoperative time were correlated for both UKA groups.

Conclusions

Reduced knee extensor moments of limbs with UKA displayed by some participants may indicate less compressive loading on the tibiofemoral joint surfaces, whereas the increased abductor moments suggest increased compression on the medial compartment. These findings suggest UKA knees may not be subjected to excessive loads regardless of the side reconstructed.

Level of Evidence

Level II, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.
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Metadaten
Titel
Knee Moments After Unicompartmental Knee Arthroplasty During Stair Ascent
verfasst von
Yang-Chieh Fu, PhD
Kathy J. Simpson, PhD
Cathleen Brown, PhD
Tracy L. Kinsey, MSPH
Ormonde M. Mahoney, MD
Publikationsdatum
01.01.2014
Verlag
Springer US
Erschienen in
Clinical Orthopaedics and Related Research® / Ausgabe 1/2014
Print ISSN: 0009-921X
Elektronische ISSN: 1528-1132
DOI
https://doi.org/10.1007/s11999-013-3128-y

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