The knee is a complex joint which contains many structures susceptible to injury. Some of the most common knee injures in an athletic population include ACL and MCL tears, meniscus tears, and patellar pain. The knee joint contains bones, cartilage, ligaments, and tendons along with other neurovascular structures. The knee is made up of four bones: the femur, tibia, fibula, and the patella or kneecap. The meniscus is the C shaped shock absorber cartilage between the tibia and the femur. The ligaments in the knee include the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the medial collateral ligament (MCL) and the lateral collateral ligament (LCL).
The two most common ligament injuries in the knee are ACL and MCL tears. Both ligaments provide stability to the knee, in different planes. The MCL is a broad ligament on the inside of the knee that is commonly injured with a blow to the outside of the knee or when the knee goes inward. The injury is typically associated with moderate pain and swelling in the knee as well as tenderness on the inside of the knee. MCL injuries are grade on a scale of 1-3, depending on their severity. A majority of MCL tears can be treated nonsurgically with physical therapy to manage swelling, restore range of motion, and strengthen for return to activity.
The ACL attaches from the tibia to the femur and provides stability to the knee joint. ACL injuries typically occur with a twisting or hyperextension mechanism and are often associated with other trauma to the knee such as meniscus or MCL injuries. ACL injuries most commonly occur in non-contact situations; therefore, prevention of these injuries can be significant in populations who are at greater risk such as female athletes. ACL injuries are treated surgically, and rehabilitation is imperative in restoring full range of motion, strength, balance, and proprioception after surgery for safe return to sport. Sometimes pre-hab can be beneficial in acute ACL tears to manage swelling and improve range of motion prior to surgery to improve post-surgical outcomes.
The meniscus is made up of two C-shaped cartilaginous discs that act as shock absorbers in the knee. Meniscal injuries can be acute, chronic, or a combination of the two. Acute meniscus tears often result from a twisting mechanism and cause pain, swelling, and occasionally clicking or catching in the knee. Chronic injuries aren’t related to a specific incident and are more common in an older population. Chronic tears can also cause swelling and pain in the knee. The location and size of the meniscus tear typically dictates treatment. Sometimes small meniscus tears can be treated conservatively with physical therapy. Typically, acute tears or large degenerative tears are treated surgically, followed by rehabilitation.
Patellofemoral pain describes pain originating from poor tracking of the kneecap (patella) on the thighbone (femur), causing pain at the front of the knee. The condition is commonly due to overuse and poor structural alignment, often from muscular weakness or imbalance. Patellofemoral pain syndrome is frequently diagnosed in runners, skiers, and athletes in jumping sports. Pain is typically worse with going down stairs. This pathology is addressed with activity modification in the initial phases and physical therapy to restore proper muscle balance and alignment. It is important to identify which muscles are weak, typically muscles in the thigh and the hip, and which are too tight, often the hamstrings, iliotibial band ,and hip flexor. Performing targeted exercises to address these imbalances and reduce load through the patellofemoral joint usually addresses the condition successfully.
There are numerous factors that can help you to prevent the injuries discussed above. By maintaining adequate strength in your gluteal muscles, leg muscle, and core, as well as having adequate flexibility and staying active, you can decrease your risk of acute and chronic knee injury. Some of the best exercises to decreased load to the knee joint are the lateral band walk, single leg squats, ball bridges, and planks. Seeing a physical therapist can help you to ensure that you are performing preventive strengthening and stretching exercises correctly.
Amber Davenport, DPT, Aspen Club Sports Medicine Clinic, earned her doctorate in physical therapy from the University of Colorado Health Sciences Center. Her specialty treatment areas are orthopedics, sports medicine, and women’s health physical therapy. Learn more about Ms. Davenport here.