The human knee is the largest joint in the body. It is composed of the Tibia, Femur and Patella bones; the joint surfaces of which are covered in cartilage which allows smooth movement and gliding of the joint surfaces. There are multiple structures around the knee which hold the bones in place and allow the movement to occur and due to the significant forces generated, the knee is very prone to injury.
1. Ligaments – ACL / PCL / MCL / LCL
Below, we discuss the most common type of knee injury, how this is managed at The Knee Clinic Manchester, and what you can do to avoid injury.
The Anterior cruciate ligament (ACL) is the most commonly injured ligament in the knee (90% of all ligament injuries are ACL). In the UK, around 15 000 ACL reconstruction operations are carried out each year and around 400 000 in the USA.
The ACL sits in the middle of the knee and attaches the femur to the tibia. It has two main bundles which act to stabilise the knee throughout the range of movement from extension to deep flexion. The ACL provides 85% of the stability to stop excessive anterior movement of the tibia in relation to the femur.
Female athletes are more at risk than male with a injury ratio of 4:1. Females sustain injuries at a younger age and are more likely to injure the supporting leg than the kicking leg. The reason for this is that females have different landing biomechanics and neuromuscular activation leading to a this disposition.
The most common mechanism of injury is a NON-CONTACT pivoting injury, as the tibia translates anteriorly in slight flexion and valgus strain. It can also be injured with a direct blow to the outside of the knee. The commonest sports are sports that involve pivoting and cutting movements e.g. football, basketball, rugby, and skiing.
ACL injuries are usually high energy and so other structures like meniscus , other ligaments and cartilage are also injured in around 60-70% of cases; with the lateral meniscus being most common (50%)
A big “pop” is usually felt in the knee with an immediate large swelling, as the ACL ruptures and bleeds into the knee.
The knee injury is serious if the joint swells very quickly, you can’t put weight through the knee or the knee range of movement becomes drastically reduced i.e. you can’t move the knee.
In the immediate post injury phase, we would advise icing the knee asap and attending a hospital or specialist clinic like The Knee Clinic Manchester, for assessment.
In the current climate, waiting times in Accident and Emergency can be extremely frustrating. We are specialists in assessing and managing these injuries and have the highest quality team approach to get you moving and back on your feet asap.
The assessment involves an X-ray to exclude fracture and then an MRI scan. A brace can be fitted to help support the knee during the first 2-6 weeks and get it moving, and start rehabilitation.
Based on the MRI scan and physical examination, the correct treatment will be discussed. Physiotherapy to get the knee moving is essential whether surgery is advised or not.
If an ACL reconstruction is needed, then pre-habilitation with a good physio, will be needed, as well as informed consent and planning for the procedure.
Many knee injuries can be treated with simple measures, such as:
• Immobilization. Your doctor may recommend a brace to prevent your knee from moving. If you have fractured a bone, a cast or brace may hold the bones in place while they heal. To further protect your knee, you may be given crutches to keep you from putting weight on your leg.
• Physical therapy. Specific exercises will restore function to your knee and strengthen the leg muscles that support it.
• Nonsteroidal anti-inflammatory drugs (NSAIDs). Anti-inflammatory drugs like ibuprofen and naproxen reduce pain and swelling.
Many fractures and injuries around the knee require surgery to fully restore function to your leg.
In some cases — such as for many ACL tears — surgery can be done arthroscopically using miniature instruments and small incisions. Learn more: Knee Arthroscopy
Fractures, on the other hand, often require open surgery with a larger incision that provides your surgeon with a more direct view and easier access to the injured structures.
SOURCE: Department of Research & Scientific Affairs, American Academy of Orthopaedic Surgeons. Rosemont, IL: AAOS; February 2014. Based on data from the National Ambulatory Medical Care Survey, 2010; Centers for Disease Control and Prevention.
Get in touch for more details or if you want to discuss ACL reconstruction surgery.
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