300 Section - Assessment of the Demographic Factors that Impact Quadriceps Femoris Size and Strength in Patients after Arthroscopic Knee Surgery

Wednesday, May 20, 2026

6:00 PM - 7:30 PM PT

Presenting Author/Autor expositor(s)

gR

gintare Repeckaite, MD

Phd student
Lithuanian University of Health and Science
Kaunas, Kauno Apskritis, Lithuania

Co-Author/Coautor(s)

RR

Raimondas Raimondas Kubilius, PhD

Professor
Lithuanian University of Health and Science
Kaunas, Kauno Apskritis, Lithuania

Objectives : To investigate the impact of demographic factors: age, sex and body mass index on quadriceps femoris strength and size after arthroscopic knee surgery

Design: The study included 35 patients (20 men (57.1%); 15 women (42.9%)), who underwent arthroscopic knee surgery (ACL or meniscus repair surgery) and were assigned to outpatient rehabilitation. Muscle strength was measured with an isometric hand held dynamometer (Lafayet, USA), muscle size was assessed by ultrasound (Mindray DC-80A, Hamburg, Germany) examination using cross sectional area (CSA) method. Demographic factors: age, sex, BMI were collected. Spearman correlation analysis was performed to determine the relationship between the two distributions

Results: Age was negatively correlated with QF size: older age was associated with smaller CSA of the VM ( ρ = −0.393, p < 0.05) and RF (ρ = −0.356, p < 0.05). Sex differences were observed for VM CSA in the operated (right) thigh; males demonstrated a significantly greater VM CSA compared with females (p < 0.01). No significant associations were identified between BMI and QF CSA (p > 0.05).

Conclusion: In this cohort, increasing age was significantly associated with reduced CSA of the VM and RF, indicating age-related quadriceps muscle atrophy. Male patients had a significantly larger VM CSA in the operated right thigh compared with female patients. BMI was not significantly related to quadriceps muscle size. These findings suggest age and sex influence quadriceps morphology after surgery, whereas BMI does not appear to predict baseline muscle size in this setting.