An anterior cruciate ligament (ACL) injury is one of the most common knee injuries. It involves the ACL being stretched, partially torn or completely torn, with the latter being the most common. About half of all injuries to the ACL also involve damage to other structures in the knee, such as cartilage, meniscus or other ligaments. It is important that there is no delay in diagnosis or the correct level of treatment, to ensure that you can return to your everyday activities.
The Ligaments of the Knee
This diagram shows where the ACL is in the knee joint.
An ACL injury can occur in a number of ways, including:
- A sudden change in direction;
- Coming to a stop suddenly or slowing down while running;
- Landing awkwardly when jumping;
- A direct collision when playing contact sports.
There may be a “popping“ sound and the knee may give way. There are other classic signs, including:
- The knee joint being tender.
- Pain in the knee.
- Swelling, which will typically develop within 24 hours.
- Discomfort when walking.
- Not being able to move the knee through a full range of motion.
However, it is important to note that not all of these symptoms will be present. In addition, the pain and swelling may resolve by itself. However, return to physical activities could result in further injury due to the knee being unstable.
A physical examination is the first step to diagnosis. A hospital doctor, a general practitioner, or a physiotherapist could do this.
The clinician will check all the structures of the injured knee, with comparison made to the uninjured knee. They will use specific tests to see whether the ACL is intact and if the forward motion of the shinbone (tibia) is limited.
An MRI scan might be arranged if there is doubt over the diagnosis, or to check for damage to other structures in the knee. An x-ray can identify any fractures associated with the injury.
The treatment of an ACL injury will depend upon the severity of the injury, i.e. if stretched, partially torn or completely torn. Looking at the most common type, a complete tear, the need for surgery will come down to your individual circumstances. If you are a younger person involved in sports involving pivoting on the knee then it is likely that you will need surgery to return to your previous activities. However, if you are less active and/or older, you may be able to return to your normal lifestyle without surgery.
A torn ACL will not heal without surgery, but if you can return to your normal lifestyle without surgery, you might be provided with a knee brace and crutches, or physiotherapy to restore function to the knee and to improve the strength in the supporting leg muscles.
Torn ACLs cannot be simply stitched back together. Surgery, known as ACL reconstruction, involves replacing the damaged ligament with a graft of tendon. A graft can be taken from various sources, including the tendon from the kneecap to the shinbone, the hamstring tendon or sometimes even a cadaveric graft can be used.
The ACL reconstruction itself is performed by making small incisions and using a scope, similar to keyhole surgery. This is known as arthroscopic surgery and it is less invasive which should mean less pain and quicker recovery times.
Making a claim
At Pryers we often receive enquiries regarding ACL injuries.
Claims most commonly arise from poorly performed ACL reconstruction surgery – often due to incorrect placement of the graft. Tamlin Bolton, a Senior Solicitor on our medical negligence team, settled a claim like this. She secured £22,000 compensation for a young footballer who was unable to play for four years, after negligent surgery to repair an ACL injury prolonged her recovery.
But claims also arise because of a delay in diagnosing the original injury, or inappropriate referral to a specialist for treatment. A delay in diagnosis might result in a longer period of pain and suffering, or in more severe cases, permanently impaired function of the knee, which can have a significant impact on your daily life.