Вплив нахилу суглобової лінії на морфологічні параметри колінних суглобів при остеоартриті

R. I. Blonskyi; L. O. Kylymniuk

doi:10.14739/2310-1210.2026.1.339795

Authors

R. I. Blonskyi Institute of Traumatology and Orthopedics of the National Academy of Medical Sciences of Ukraine, Kyiv, Ukraine https://orcid.org/0000-0003-2310-6345
L. O. Kylymniuk Medical Centre “Angels Clinic”, Vinnytsia, Ukraine https://orcid.org/0000-0003-0170-8708

DOI:

https://doi.org/10.14739/2310-1210.2026.1.339795

Keywords:

knee joint, osteoarthritis, bone morphology, acquired joint deformities, diagnostic imaging

Abstract

Aim. To characterize the morphological parameters of the knee joint in medial osteoarthritis (OA), accounting for joint line obliquity (JLO) as assessed by a method proposed by the author (mJLO).

Materials and methods. A total of 100 standard weight-bearing anteroposterior knee radiographs from 70 patients with medial knee OA were analyzed. The following radiographic parameters were evaluated: anatomical lateral distal femoral angle (aLDFA), anatomical medial proximal tibial angle (aMPTA), femorotibial angle (FTA), joint line convergence angle (JLCA), joint line obliquity (JLO), and mJLO. Values of mJLO <177° were defined as apex distal (AD), 177–183° as apex neutral (AN), and >183° as apex proximal (AP). Statistical significance was set at p ≤ 0.05.

Results. AD was identified in 72 cases (72.0 %), AN in 25 (25.0 %), and AP in 3 (3.0 %). The mean mJLO values were: AD 172.13 ± 4.15°, AN 178.92 ± 1.53°, and AP 187.33 ± 2.52° (p < 0.00001). The corresponding values for other parameters were: FTA: AD – 175.90 ± 5.08°, AN – 179.58 ± 5.68°, AP – 185.00 ± 3.00° (p = 0.003); aLDFA: AD – 83.33 ± 2.75°, AN – 85.82 ± 2.37°, AP – 86.33 ± 3.06° (p = 0.0003); aMPTA: AD – 82.80 ± 3.28°, AN – 87.10 ± 2.50°, AP – 95.00 ± 2.65° (p < 0.00001); JLCA: AD – 4.41 ± 1.39°, AN – 3.72 ± 0.99°, AP – 3.50 ± 1.32° (p = 0.08); JLO: AD – 0.83 ± 3.52°, AN – 3.50 ± 4.15°, AP – 4.00 ± 1.00° (p = 0.009). Higher mJLO values (characteristic of the AP phenotype) positively correlated with increased FTA (τ = +0.21, p = 0.002), aLDFA (τ = +0.53, p < 0.0000001), and aMPTA (τ = +0.56, p < 0.0000001), while negatively correlating with JLCA (τ = -0.18, p = 0.007). The likelihood of the AD phenotype was significantly increased in patients with aLDFA 79–83° (OR = 3.86; 95 % CI: 1.51–11.10; p = 0.004), aMPTA ≤84° (OR = 15.35; 95 % CI: 5.05–61.75; p < 0.001), JLCA ≥4.1° (OR = 4.04; 95 % CI: 1.52–12.47; p = 0.004), and JLO <0° (OR = 3.69; 95 % CI: 1.31–12.62; p = 0.01). Conversely, the AN phenotype was more probable in patients with aLDFA ≥84° (OR = 5.56, CI (2.06–17.31), p = 0.0005), aMPTA 85–90° (OR = 4.13, CI (1.65-10.90), p = 0.002), aMPTA ≥91° (OR = 5.30, CI (1.46–20.93), p = 0.01), JLCA 2,1–4,0° (OR = 3.42, CI (1.32–9.90), p = 0.01), JLO >0° (OR = 3.03, CI (1.07–10.41), p = 0.04).

Conclusions. Morphological parameters of the knee joint in medial osteoarthritis patients significantly differ based on mJLO values.

Author Biographies

R. I. Blonskyi, Institute of Traumatology and Orthopedics of the National Academy of Medical Sciences of Ukraine, Kyiv

MD, PhD, DSc, Chief Researcher, Clinic of Sports and Ballet Injuries; Professor of the Department of Surgery No. 2, Higher Educational Establishment «Kyiv Medical University», Ukraine; Orthopedic and Trauma Surgeon of the Highest Qualification Category

L. O. Kylymniuk, Medical Centre “Angels Clinic”, Vinnytsia

MD, PhD, Orthopedic and Trauma Surgeon

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