The anterior cruciate ligament (ACL) is one of four major ligaments in the knee that provides stability during movement. Recognising the early warning signs of an ACL injury can help you seek appropriate care promptly. This article explains the common early indicators of ACL damage and when it’s appropriate to consult with a knee specialist.
What is the ACL?
The anterior cruciate ligament (ACL) is located inside the knee joint, running diagonally from the thigh bone (femur) to the shin bone (tibia).
It plays a key role in stabilising the knee by preventing the tibia from sliding forward relative to the femur, especially during twisting, pivoting, and straight-ahead movements.
The ACL is essential for everyday activities such as walking, running, climbing stairs, and maintaining balance while standing.
Early Signs of an ACL Injury
ACL injuries often happen during sports that involve sudden stops, changes in direction, or direct impacts. However, the early signs may not always be immediately apparent.
Popping sensation: Many people report hearing or feeling a “pop” at the moment of injury. This sound can indicate that the ligament has torn.
Swelling: The knee typically swells within 24 hours. This swelling may vary depending on the extent of the injury.
Pain and discomfort: You might experience pain, particularly when bearing weight on the affected leg. The pain may be sharp initially and then become a dull ache.
Instability when walking: A feeling that your knee might “give way” when walking or standing suggests that the ACL may be compromised.
Risk Factors for ACL Injuries
Understanding who is more susceptible can help you recognise potential concerns.
Sport participation: Activities that require pivoting, cutting, or jumping (like football, basketball, and skiing) are associated with ACL injuries.
Female athletes: Women tend to experience these injuries more frequently due to differences in muscle strength, hormonal influences, and anatomical alignment.
Previous knee injuries: Having injured your knee before may increase the likelihood of future ACL problems.
When to See a Knee Specialist
Not all knee pain requires immediate specialist attention, but certain signs suggest medical advice would be beneficial.
Notable swelling: If your knee swells considerably within a few hours of injury, it may indicate internal changes that warrant assessment.
Difficulty bearing weight: Trouble standing or walking on the affected leg suggests a potentially significant injury.
Feeling of instability: If your knee feels unsteady or gives way during normal activities, this could indicate ligament involvement.
Persistent pain: Pain that doesn’t respond to rest, ice, compression, and elevation over 48-72 hours merits professional evaluation.
Conclusion
Recognising the early signs of an ACL injury allows for timely care, which may influence outcomes. If you experience knee instability, swelling, or pain following an injury or during activity, consulting with a knee specialist can help determine the appropriate course of action.
Consider speaking to a knee specialist if you notice persistent knee pain, instability, or swelling, particularly after activities that involve sudden stops or changes in direction.
