Evidence map›Paper›PMID 41824050›Full record

ArticleArchives of orthopaedic and trauma surgery2026

Favorable midterm clinical results of medial unicompartmental knee arthroplasty guided by coronal limb alignment using an image-free navigation system.

Kengo Shimozaki, Shingo Shimozaki, Eiji Shimozaki

Abstract read
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Article in Archives of orthopaedic and trauma surgery, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

3 authors.

Kengo ShimozakiShimozaki Orthopaedic Clinic, 158-3 Sempukuji-machi, Hakusan, Ishikawa-ken, 924-0802, Japan. shimo.k0812@gmail.com.
Shingo ShimozakiShimozaki Orthopaedic Clinic, 158-3 Sempukuji-machi, Hakusan, Ishikawa-ken, 924-0802, Japan.
Eiji ShimozakiShimozaki Orthopaedic Clinic, 158-3 Sempukuji-machi, Hakusan, Ishikawa-ken, 924-0802, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

introductionMedial unicompartmental knee arthroplasty results in good postoperative motion and high patient satisfaction. However, inaccurate bone resection during manual procedures can cause tibial fractures, implant subsidence, or lateral compartment osteoarthritis. To improve accuracy, we performed medial unicompartmental knee arthroplasty using an image-free navigation system, with a target postoperative alignment of 2°–5° varus. This study evaluated midterm clinical outcomes and safety. MATERIALS AND

methodsThis single-center retrospective case series included 144 consecutive knees (25 in men and 119 in women; mean age, 72.2 years) that underwent medial unicompartmental knee arthroplasty for varus osteoarthritis between 2011 and 2021, with at least three years of follow-up (mean, 63.1 months). A fixed-bearing implant (Triathlon PKR; Stryker) was used in all cases. The navigation system guided tibial and femoral resections to achieve a hip–knee–ankle angle of 2°–5° varus, while minimizing tibial resection. Pre- and postoperative outcomes were compared for range of motion, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), ability to sit in the seiza position, implant survival, and complications.

resultsMean knee extension improved from − 5.7° to − 0.6°, flexion from 141.6° to 145.9°, and the mean WOMAC score improved from 41.5 ± 9.9 to 4.9 ± 3.5. The number of patients able to sit in the seiza position increased significantly. Four knees underwent lateral unicompartmental knee arthroplasty for progression of lateral osteoarthritis, and one was converted to total knee arthroplasty for infection. No tibial fractures or implant subsidence occurred. The Kaplan–Meier implant survival rate, with failure defined as reoperation for any cause, was 96.5%.

conclusionsAlignment-guided medial unicompartmental knee arthroplasty targeting 2°–5° varus using image-free navigation achieved favorable midterm outcomes without major complications. LEVEL OF EVIDENCE: Level IV.

Indexed as

Arthroplasty, Replacement, KneeOsteoarthritis, KneeSurgery, Computer-AssistedAgedAged, 80 and overFemaleHumansKnee ProsthesisMaleMiddle AgedRange of Motion, ArticularRetrospective StudiesTreatment OutcomeCoronal limb alignmentMedial unicompartmental knee arthroplastyMidterm outcomesNavigation

Identifiers

PMID41824050
PMCPMC12987780

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.