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Joint Diseases and
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Original Article · Open access

Impact of postoperative femorotibial axis on functional outcomes in unicompartmental knee arthroplasty

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Anıl Köktürk

Department of Orthopedics and Traumatology, Antalya City Hospital, Antalya, Türkiye

ORCID: 0000-0002-7767-6880

Mehmet Ali Tokgoz

Department of Orthopedics and Traumatology, Gazi University Medical Faculty, Ankara, Türkiye

ORCID: 0000-0002-4056-3743

Nazli Busra Cigercioglu

Hacettepe University, Musculoskeletal Physiotherapy and Rehabilitation, Ankara, Türkiye

ORCID: 0000-0001-5912-4196

Gul Baltaci

Department of Physiotherapy and Rehabilitation, Eastern Mediterranean University, Famagusta, Turkish Republic of Northern Cyprus

ORCID: 0000-0002-6513-2499

Hamza Özer

Department of Orthopedics and Traumatology, Gazi University Medical Faculty, Ankara, Türkiye

ORCID: 0000-0001-5107-637X

Abstract

Objectives: This study aimed to compare the functional outcomes of patients undergoing fixed-bearing medial unicompartmental knee arthroplasty (UKA) classified as either varus or neutral based on their postoperative femorotibial angle (FTA), with the goal of evaluating the impact of FTA on functional results.

Patients and methods: A total of 38 knees of 35 patients (27 females, 8 males; mean age: 63.6±7.1 years; range, 52 to 75 years) were included in this retrospective study. The data was collected between December 15, 2020, and January 15, 2021. Patients were categorized into two groups based on their postoperative FTA. The neutral group consisted of patients with an FTA range of 5.1° to 7.4°, while the varus group included patients with an FTA range of 0.1° to 4.8°. Knee Outcome Osteoarthritis Score (KOOS), Visual Analog Scale (VAS) scores, sit to stand test results, and six minute walk test data were analyzed.

Results: The mean follow-up was 42.0±19.3 months. The postoperative VAS score for the varus group was 0.95±0.99, whereas the neutral group had a VAS score of 2.19±1.83 (p=0.021). The mean KOOS for the varus group was 88.01±7.88, whereas the neutral group had a mean KOOS score of 78.46±13.69 (p=0.006).

Conclusion: In patients undergoing UKA, mild varus alignment could yield superior early and midterm functional outcomes compared to a neutral femorotibial angle.

Declarations

Ethics Committee Approval

he study protocol was approved by the Gazi University Clinical Research Ethics Committee (date: 14.12.2020, no: 032). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Informed Consent

A written informed consent was obtained from each patient.

Author Contributions

Idea/concept, design, data collection and/or processing, literature review, writing the article, materials: A.K.; Analysis and/or interpretation, writing the article, materials: M.A.T.; Data collection and/or processing, literature review, references and fundings: N.B.C.; Control/ supervision, critical review: G.B.; Control/supervisin, critical review, materials: H.Ö.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

The authors received no financial support for the research and/or authorship of this article.

Data Sharing Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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