MORPHOLOGICAL VARIATION OF KNEE JOINTS IN DEGENERATIVE-DYSTROPHIC DISEASES

Liubov  Kylymniuk; Maksym  Matsipura; Stanislav  Iaremyn

doi:10.21272/eumj.2026;14(2);594-604

Liubov Kylymniuk Medical Center "Angels Clinic", Vinnytsia, Ukraine https://orcid.org/0000-0003-0170-8708
Maksym Matsipura Department of Traumatology and Orthopedics of National Pirogov Memorial Medical University, Vinnytsia, Ukraine https://orcid.org/0000-0002-5631-8056
Stanislav Iaremyn Department of Traumatology and Orthopedics of National Pirogov Memorial Medical University, Vinnytsia, Ukraine https://orcid.org/0000-0001-9826-6859

DOI: https://doi.org/10.21272/eumj.2026;14(2);594-604

Keywords: knee joint, degenerative-dystrophic diseases, osteoarthritis, diagnosis, morphology, classification, gonarthrosis

Abstract

Introduction. Structural differences in knee joints associated with sex, height, body weight, individual characteristics and ethnic origin have been confirmed by numerous studies. However, the issue of segmenting a heterogeneous population of patients with degenerative-dystrophic knee joint diseases remains unresolved. Understanding the morphological variability of knee joints may contribute to improving orthopedic intervention techniques in line with the principles of personalized surgery and enhancing clinical outcomes in patients with degenerative-dystrophic knee conditions. Aim: To characterize the prevalence of morphological variants of the knee joint in patients with degenerative-dystrophic diseases, based on a modified Coronal Plane Alignment of the Knee (CPAK) classification and a custom clustering system.

Materials and Methods. Radiographic examination of 100 cases of degenerative medial knee joint disease were analyzed. The average age was 63.56±8.10 years. The structural variants of the knee joint were assessed using a modified CPAK classification and a custom clustering system. Based on the clustering of morphometric indicators, morphotype I was identified in 21 patients (21.00 %), morphotype II in 38 patients (38.00 %), morphotype III in 29 patients (29.00 %), and morphotype IV in 12 patients (12.00 %). Statistical analysis was conducted using Statistica 13 software, with a significance level set at p≤0.05.

Results. The mean value of the modified joint line orientation (mJLO) in the examined patients was 174.28±5.20°, and the mean arithmetic hip-knee-ankle angle (aHKA) was 0.19±4.74°, indicating a predominantly distal orientation of the joint line and neutral lower limb alignment in patients with degenerative-dystrophic knee diseases. A distal apex of the joint line was observed in 72 patients (72.00 %), a neutral position in 25 patients (25.00 %), and a proximal position in 3 individuals (3.00 %). aHKA values < -2° were recorded in 35 patients (35.00 %), values within ±2° in 41 patients (41.00 %), and values > 2° in 24 patients (24.00%). According to the modified CPAK classification, the most common knee joint types were type I (30.00 %), type II (28.00 %), and type III (14.00 %).

Conclusion. The study confirmed the morphological variability of knee joints in degenerative-dystrophic diseases.

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