What orthopedic issue is due to a problem with the lateral collateral ligament?

The correct answer, which identifies genu varum as the orthopedic issue related to a problem with the lateral collateral ligament (LCL), is rooted in an understanding of the anatomical and functional relationships of the knee joint.

Genu varum, commonly known as "bow-leggedness," involves an outward angulation of the knee joints. This condition can occur when there is instability or injury to the lateral collateral ligament. The LCL runs along the outer part of the knee and plays a critical role in providing lateral stability. When the LCL is compromised, the knee may buckle under pressure, leading to a bowing effect on the lower limbs.

Understanding genu varum in this context is essential as it highlights the clinical relevance of ligament function in maintaining proper knee alignment and support during movement.

In contrast, genu valgum, often referred to as "knock-knees," involves an inward angulation of the knees and is typically related to different knee mechanics, not LCL instability. Patellar bursitis pertains to inflammation of the bursa around the kneecap, which does not directly relate to the collateral ligaments. Hip dysplasia is a developmental condition affecting the hip joint, unrelated to the stability of the knee or the lateral collateral ligament.