The knee is one of the most commonly injured regions of the human body. Its location in relation to the rest of the body places it at high risk of injury due to the forces that it has to bear – running, jumping, cutting, pivoting, squatting and lunging during physical activity can excessively load the knee if it is not conditioned to handle it and/or movement patterns are not efficient. The knee is also susceptible to injury when it receives a direct blow such as in a car accident, fall or when playing sport.
We will take a look at which knee injuries are the most common and give you info on how to treat and prevent these injuries.
Anatomy Of The Knee
The knee joint consists of the femur (thigh bone), tibia (shin bone), fibula (calf bone located to the outer side of the shin bone) and patella (knee cap); all connected together by the ligaments, muscles and tendons that surround the joint. Its primary movements are flexion and extension and to a lesser degree, rotation.
In order for the knee to function optimally and avoid injury, these movements need to be unrestricted and coordinated correctly when performing activities that load the knee. This requires the knee to have adequate mobility, stability, strength and movement patterns in order to handle these loads.
Symptoms & Signs Associated With Knee Injury
Depending on the type, location and severity of the knee injury, various symptoms might occur.
Injured structures located OUTSIDE the knee joint capsule (the ligamentous sac that surrounds the joint) such as the patella tendon, patellofemoral structures or ITB might cause the following symptoms:
- Varying levels of pain
- Mild to no swelling
- Mild to no loss of range of motion (although joint stiffness might be present)
- Painful crepitus (creaking, grinding, grating sensations)
These injuries usually occur as a result of overuse.
Injured structures located INSIDE the joint capsule such as the major ligaments (ACL, PCL, MCL), meniscus, bone or cartilage might cause the following symptoms:
- Moderate to severe pain
- Moderate to severe swelling
- Moderate to severe loss of range of motion
- Joint catching, locking or giving way in more severe cases
These injuries usually occur as a result of a traumatic incident.
How To Treat A Knee Injury
The cornerstone of any good rehab programme is LOAD MANAGEMENT. Your knee is loaded when you do physical activity (competitive or recreational) and when you perform specific rehab exercises. It is important to manage the amount of load applied to the injured knee at every stage of the process. Both over- and underloading can result in less than optimal results. Doing the appropriate amount of physical activity along with strength, mobility and stability rehab exercises, can increase the ability of the knee to tolerate load without significantly increasing symptoms. Doing this over a period of time can decrease knee pain and increase function. Read more about our injury rehabilitation treatment here.
Types Of Knee Injuries
Knee injuries can be classified into 2 main categories:
- Overuse
- Traumatic (might require surgery)
Overuse Knee Injuries
Overuse knee injury is caused by activities that place excessive load on the knee over a period of time (not a single injury incident). Examples include:
- Patellofemoral pain
- Patella tendinopathy
- Iliotibial tibial band (ITB) syndrome
Traumatic Knee Injuries
Traumatic knee injury is caused by the knee being involved in an injury incident. Depending on severity, these injuries might require surgery. Examples include:
- ACL (anterior cruciate ligament) injury
- Meniscus injury
- MCL (medial collateral ligament) injury
Let’s take a look at each of these knee injuries in more detail.
6 Most Common Knee Injuries & How To Treat Them
1. Patellofemoral Pain a.k.a. Runner’s Knee
The connection between the patella (knee cap) and the underlying femur (thigh bone) is known as the patellofemoral joint. Patellofemoral pain is caused by excessive running, jumping, squatting or lunging activities that stress the joint more than it can handle. This injury is often referred to as “Runner’s Knee” because of its high prevalence amongst runners.
Characterised by: Pain located anywhere around or behind the patella.
Treatment:
A combination of pain-free knee and hip strengthening exercises should be performed. This might take the form of exercises that isolate individual muscles along with exercises that resemble the tasks you struggle with. Other useful interventions include modifying running gait, knee taping/bracing, foot orthoses. These should always be used in combination with exercise-based interventions. Gradual progression is key to minimising flare-ups in your pain.
Top Tip: Have a look at our comprehensive post detailing all you need to know about Runner’s Knee here.
2. Patella Tendinopathy a.k.a. Jumper’s Knee
The patella tendon connects the bottom of the patella (knee cap) to the upper tibia (shin bone). Patella tendinopathy is caused by excessive explosive activities such as jumping, sprinting and rapid changing direction. This injury is often referred to as “Jumper’s Knee” – named after the activity that most often causes this injury.
Characterised by: Pain in a very specific location just below the patella, on the patella tendon.
Treatment:
The patella tendon connects the quadriceps muscle to the tibia. Therefore performing heavy, slow resistance exercises that focus on quadriceps strength can increase the load capacity of your patella tendon. Mild to moderate pain when doing these exercises is acceptable, as long as pain subsides back to normal levels for you, by the following day. Reducing or stopping explosive activities in the short term can be beneficial, especially when your patella tendon is very sensitive.
3. Iliotibial Band (ITB) Syndrome
The iliotibial band is a thick band of connective tissue that originates at the pelvis/hip and inserts on the head of the fibula (calf bone). ITB syndrome is most often caused by excessive running and aggravated especially during downhills.
Characterised by: Pain located on the outer side of the knee above or below the joint line.
Treatment:
The ITB can be loaded with resistance exercises that also stretch the hip flexor/quadriceps muscles (such as Bulgarian split squats or single leg bridges) and those that engage the lateral hip muscles (such as side leg raises or side planks). Running, especially downhill can be particularly aggravating when your ITB is sensitive. This can be substituted with intense uphill treadmill walking in order to maintain conditioning while your ITB recovers.
4. ACL (Anterior cruciate ligament) Injury
The ACL is one of the primary stabiliser ligaments of the knee. Its main functions are to prevent the tibia (shin bone) from sliding forward excessively in relation to the femur (thigh bone) and to prevent knee hyperextension. The common mechanism of injury is a rapid, unexpected movement of the knee towards the midline along with inward rotation, while the foot is planted on the ground. This can happen during a side step or pivot, or when receiving a blow to the outside of the knee while the foot is planted. The ACL is often injured in combination with the meniscus and medial collateral ligament.
Characterised by: Severe pain, swelling, range of motion and instability, which often requires surgery in order to make a full recovery.
Treatment:
Surgery is generally recommended if you want to return to high-level sports. However, non-surgical approaches have become increasingly accepted. This is a complex decision-making process so you should consult with one or more orthopaedic surgeons to help you make the best decision for your situation. Whether or not surgery is performed, in the early stages, the aim is to decrease swelling and restore flexion and extension range of motion. Quadriceps, hamstring, gluteus and calf muscle strength should be progressed until similar levels of strength is achieved between injured and uninjured sides. If the goal is to return to sport then balance, power and agility drills should be incorporated gradually and become increasingly specific to the demands of the sport.
5. Meniscus Injury
The menisci are flat, disc-like connective tissue structures that function as shock absorbers within the knee. There are two menisci – medial and lateral. The medial meniscus is more commonly injured than lateral. The common mechanism of injury is for the knee to twist excessively while the foot is planted on the ground.
Characterised by: Swelling and pain especially during knee flexion; along with catching, locking and giving way in more severe cases.
Treatment:
Surgery is often recommended when severe symptoms like joint locking and giving way persist or if non-surgical treatment has failed. As with ACL rehab, in the early stages, the aim is to decrease swelling and restore flexion and extension range of motion. Quadriceps, hamstring, gluteus and calf muscle strength should be progressed until similar levels of strength is achieved between injured and uninjured sides. If the goal is to return to sport then balance, power and agility drills should be incorporated gradually and become increasingly specific to the demands of the sport.
6. Medial Collateral Ligament Injury
The medial collateral ligament is located on the inner side of the knee joint and makes connections between the femur and tibia to provide stability by resisting forces from the outside, directed towards the inside of the knee. Injury might occur when there is direct contact with the outer side of a partially bent knee, when the foot is in contact with the ground.
Characterised by: Swelling and pain on the inner side of the knee. In moderate to severe cases the knee might feel varying degrees of instability.
Treatment:
In the vast majority of cases, a non-surgical approach is recommended. A knee brace can provide support and protection during the first 4 to 6 weeks of rehab. As with ACL and meniscus rehab, in the early stages, the aim is to decrease swelling and restore flexion and extension range of motion. Quadriceps, hamstring, gluteus and calf muscle strength should be progressed until similar levels of strength is achieved between injured and uninjured sides. If the goal is to return to sport then balance, power and agility drills should be incorporated gradually and become increasingly specific to the demands of the sport.
How To Prevent Knee Injury
Educate yourself – get a better understanding of the physical activity you participate in, so that you can identify the positions, movements and situations that cause knee injury. Predicting these before they happen can help you effectively avoid injury.
Train smart – Avoid big increases in intensity, duration and frequency of activities that stress your knee. Progress gradually, especially after taking a break from activity.
Rest and recover – Take rest days, especially between higher intensity training sessions. Work to reduce stress and improve sleep, nutrition & hydration.
Top 3 Exercises To Help Strengthen Your Knee
We recommend the following exercises to help strengthen your knee.
1. Leg extensions
The quadriceps is arguably the most important muscle group to rehabilitate for most knee injuries because of the high demands placed on it during activity. The leg extension is the best exercise for isolating the function of the quads.
2. Leg curls
The hamstrings need to be in balance with the quads in order for the knee to function optimally. Leg curls are excellent at increasing hamstring strength for this purpose.
3. Single leg squats
This is one of the most functional exercises because of its carry over to many different sporting movements and daily activities. Incorporating single leg squats into your routine will help you coordinate the use of individual muscles as a cohesive unit to improve your function.
Get A Professional Diagnosis
Relying solely on Doctor Google to diagnose your injury can sometimes be more harmful than helpful. We recommend seeing a professional to help you identify the cause and provide you with a tailored rehabilitation plan. If you have any questions, feel free to contact us here or book an appointment with one of our Biokineticists.
Disclaimer: This content is not medical advice and is intended for general education purposes only. It should not be used to self-diagnose or self-treat any medical condition. Do not use this information to avoid going to your own healthcare professional or to replace the advice they give you. Dhansay & Roberts Biokineticists makes no representations about the accuracy or suitability of this content.