Is the Citak classification of distal femur morphology age and gender dependent?

The purpose of this study was to compare the distal femur morphology in different age and gender groups using the Citak classification.

All patients who had standard knee anteroposterior radiographs between 2010 and 2020 were retrospectively reviewed using the electronic patient database. Patients were divided into three age groups as follows: young adults (Group I, younger than 50 years), middle-aged adults (Group II, ranging from age 51 to 73 years), and elderly (Group III, more than 74 years). From each age group, 80 patients were randomly selected with an equal number of gender (40 males/40 females). An age-stratified selection was applied to obtain the best sample that represents the selected age groups. Patients younger than 18 years of age, history of previous fracture or surgical procedure, those with fixation implants or prosthesis, and abnormalities of the lower limb, such as a congenital deformity, were excluded from the study. All measurements were performed by an experienced orthopedic surgeon familiar with the Citak classification. All measured variables were compared between age and gender groups.

There were 240 patients (120 male and 120 female) with a mean age of 59.6 ± 20.4 (range 18-95). The distal femur morphology index was similar (p:0.811), and the morphological types were equally distributed among age groups (p:0.819). Furthermore, there was no significant difference between genders on the measured variables (p > 0.05 for all variables). Citak classification types were similarly distributed between the genders (p:0.153). No correlation was found between age and the Citak index in either gender (p:0.967 and p:0.633, respectively).

Distal femoral morphology classified by the Citak index is not age and gender dependent. Type C, which has a wider diaphyseal diameter, and is supposed to be more common in elderly subjects, was equally distributed in all age groups.

Level IV. Retrospective case series.