The Science of Meniscal Injuries
The meniscus is fibrocartilage that cushions and stabilizes the knee. Tears can be traumatic (usually in younger people) or degenerative (older adults). Degenerative tears are often part of early osteoarthritis. The outer third has blood supply and can heal, while the inner portion has poor healing capacity.
Contributing Factors
Meniscus tears happen through two distinct mechanical patterns. Traumatic tears in younger athletes typically occur during cutting or pivoting movements when the foot is planted and the knee twists, trapping the meniscus between the femur and tibia. This mechanism is particularly dangerous when the knee is slightly bent and rotates under load - like when you plant your foot to change direction in sports.
Degenerative tears follow a different pattern and are much more common after age 40. These develop gradually from repetitive compressive and rotational forces during normal activities. As we age, the meniscus becomes less elastic and more prone to tearing from everyday movements like squatting, kneeling, or even getting up from a low chair. The wear and tear is often accelerated by previous knee injuries, muscle imbalances, or activities involving repeated knee rotation under load.
Poor movement mechanics significantly contribute to meniscus problems. Weak glutes and hip muscles fail to control your thigh position, allowing excessive inward collapse of the knee during activities. This altered loading pattern places abnormal stresses on specific areas of the meniscus rather than distributing forces evenly. Tight IT bands or hamstrings can also alter knee mechanics, creating uneven wear patterns on the meniscus over time. Once the meniscus is damaged, it can catch or pinch during normal knee movement, creating mechanical symptoms like clicking, locking, or catching.