There are four main ligaments in the knee that contribute to the stability of the knee.
The Anterior Cruiciate Ligament (ACL)
The ACL is one of the four ligaments in the knee, and plays a crucial role in knee movement and
protection. ACL injuries are common among athletes in sports like football, basketball, soccer,
and rugby, but can also occur in older individuals due to slip and fall accidents. An ACL injury typically happens when the front of the leg experiences direct impact while the knee is stationary. Symptoms include a sudden popping sound, pain, and swelling around the knee. To protect the knee, a knee brace may be recommended, along with physiotherapy. Depending on the severity, surgery may be necessary to repair or replace the torn ligament, followed by rehabilitation. Early treatment focuses on pain management and reducing swelling. As rehabilitation progresses, exercises such as stationary bike riding help improve knee flexibility and strength/endurance. More challenging exercises that target ambulation and balance are introduced later on. Physiotherapy continues until balance and mobility improve significantly.
The Posterior Cruciate Ligament (PCL)
The PCL prevents the knee from translating backward and is less commonly injured than the ACL. PCL tears usually result from excessive knee hyperextension or twisting. This ligament is injured less frequently and a different rehab protocol is offered for this condition.
The Medial Collateral Ligament (MCL)
The MCL is located on the inner side of the knee joint and prevents excessive side-to-side movements. MCL sprains or tears often occur along with ACL and medial meniscus tears due to high-impact blows or knee twisting. This is a common injury and the outcome of therapy is often very good after a combination of exercises, along with approaches including acupuncture, laser, cupping, heat and ice.
The Lateral Collateral Ligament (LCL)
The LCL is situated on the outside of the knee joint and also prevents excessive side-to-side movements. This ligament is commonly affected in sports and like the other conditions mentioned above, a progressive protocol involving manual therapy, exercise and modalities such as laser, ultrasound, cupping, guasha and balance exercises will help restore full function.
References
1. Fleming, J. D., Ritzmann, R., & Centner, C. (2022). Effect of an Anterior Cruciate
Ligament Rupture on Knee Proprioception Within 2 Years After Conservative and
Operative Treatment: A Systematic Review with Meta-Analysis. Sports Medicine
(Auckland), 52(5), 1091–1102. https://doi.org/10.1007/s40279-021-01600-z
2. Winkler, P. W., Zsidai, B., Wagala, N. N., Hughes, J. D., Horvath, A., Senorski, E. H.,
Samuelsson, K., & Musahl, V. (2021). Evolving evidence in the treatment of primary and
recurrent posterior cruciate ligament injuries, part 1: anatomy, biomechanics and
diagnostics. Knee Surgery, Sports Traumatology, Arthroscopy : Official Journal of the
ESSKA, 29(3), 672–681. https://doi.org/10.1007/s00167-020-06357-y
3. Yaras RJ, O’Neill N, Yaish AM. Lateral Collateral Ligament Knee Injury. [Updated 2022
May 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.
Available from: https://www.ncbi.nlm.nih.gov/books/NBK560847/