Evidence map›Paper›PMID 39833818›Full record

ArticleBMC musculoskeletal disorders2025

Varus/valgus angle of the femoral component relative to the tibial component increases risk of bearing dislocation in medial mobile bearing unicompartmental knee arthroplasty.

Shaokui Nan, Chao Li, Haoming An, Yuda Lian, Haifeng Li

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Article in BMC musculoskeletal disorders, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

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3 · Its place in the literature

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1 citing paper in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

5 authors.

Shaokui Nan *Senior Department of Orthopedics, The Fourth Medical Center of PLA General Hospital, No. 51 Fucheng Road, Beijing, 100048, People's Republic of China.
Chao Li *Senior Department of Orthopedics, The Fourth Medical Center of PLA General Hospital, No. 51 Fucheng Road, Beijing, 100048, People's Republic of China.
Haoming An *Senior Department of Orthopedics, The Fourth Medical Center of PLA General Hospital, No. 51 Fucheng Road, Beijing, 100048, People's Republic of China.
Yuda LianDehua Affiliated Hospital of Huaqiao University, Quanzhou, People's Republic of China.
Haifeng LiSenior Department of Orthopedics, The Fourth Medical Center of PLA General Hospital, No. 51 Fucheng Road, Beijing, 100048, People's Republic of China. lihaifeng0524@163.com.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundIn medial mobile-bearing unicompartmental knee arthroplasty (MB-UKA), the position of the bearing does not correspond to the planned position which will increasing the risk of bearing dislocation. This study aimed to explore the relationship between the malposition of the femoral and tibial components and the phenomenon of bearing deviation using postoperative radiological measurements.

methodsOne hundred twenty patients who underwent mobile-bearing uni-compartmental knee arthroplasty (MB-UKA) at our hospital between January and August 2023 were enrolled in this retrospective study. Standard anteroposterior radiographs were obtained postoperatively using C-arm fluoroscopy. A 3D-2D image matching method was used to measure the femoral component varus/valgus angle and internal/external rotation (IR/ER) relative to the tibial component. The bearing position parameters were measured. Patients were divided into varus/valgus and IR/ER groups according to the femoral component varus/valgus and IR/ER angles. The bearing position parameters of each group were compared separately.

resultsThere were 57 patients in the varus group, 63 in the valgus group, 59 in the IR group, and 61 in the ER group. The distance between the bearing lateral edge and the lateral wall of the tibial component (W-BED) was significantly lower in the varus group than the valgus group (1.9 [0-6.4] vs. 2.8 [0.3-7.7] mm; P < 0.001). No differences were detected in any bearing position parameters. The varus/valgus angle of the femoral component showed a significant negative correlation with the W-BED. The IR/ER angle of the femoral component showed no significant correlation with any of the positional parameters.

conclusionsImplantation of femoral component with varus/valgus angle relative to tibial component can cause the bearing to deviate from the planned position. If the varus/valgus angle exceeds 8° it can cause the bearing to hit or away from the lateral wall of the tibial component, resulting in an increased risk of dislocation of the bearing.

Indexed as

Arthroplasty, Replacement, KneeFemurKnee JointKnee ProsthesisOsteoarthritis, KneeProsthesis FailureTibiaAgedAged, 80 and overFemaleFluoroscopyHumansMaleMiddle AgedProsthesis DesignRetrospective StudiesBearing dislocationMobile-bearingOxford uni-compartmental knee arthroplastyUni-compartmental knee arthroplasty

Identifiers

PMID39833818
PMCPMC11744872

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