What Does a Healthy Knee Look Like: Normal Joint Anatomy

The knee is one of our most complex yet essential joints, allowing us to move freely without pain when in our healthiest form.

It’s often taken for granted – the freedom we have when our bodies work precisely as they’re designed to.

Yet for many of us, knee problems arise, such as a knee injury, wear and tear, damage to soft tissues, and age-related bony degeneration.

So, to answer the question: What does a healthy knee look like? It simply means a knee that functions as usual, with no pain or discomfort to the individual.

There is no ‘normal’ per se; it’s what’s normal for the person and their general health (if that makes sense…)

In this blog post, we’ll explore the anatomy of the knee joint, along with typical causes of knee pain and injuries.

We’ll also briefly look at diagnostic tests to detect knee injuries and treatment options to help you keep your knees healthy and strong.

Whether you’re looking for ways to prevent knee problems or dealing with knee pain, this article will surely provide valuable insight.

Largest Joint – The Knee

Knee Anatomy

The knee joint happens to be the largest in the body, made up of the thigh bone (femur), shin bone (tibia), and the knee cap (patella).

Its function is to connect the lower leg bones with the upper leg bones so we can move our legs.

Together, these bones form the ‘hinge joint’ that we know as ‘the knee’.

The knee is what enables our legs to bend and flex.

Being the complex joint it is, the knee contains two sets of ligaments, four muscles, three tendons, several cartilage surfaces, and a synovial membrane, all of which work in symphony to provide stability and mobility. That’s a lot of anatomy!

The first set of ligaments are:

• The ACL – located at the front of the knee joint.
• The PCL – located at the back of the knee joint.

The second set of ligaments is found on the sides of the knee. These are:

• The MCL – found on the inner side
• The LCL – found on the outer side

Now, there are muscles which wrap around the knee joint providing strength; these help act as shock absorbers when we walk, run, or do anything of high impact, such as jumping from a height.

The quadriceps muscle at the front of our thigh helps straighten our legs. it attaches to our patella via a tendon known as the quadriceps tendon.

At the back of the thigh, you’ll find another large muscle, the hamstring, which helps us bend our knees when we walk or run. This muscle attaches to our tibia via the hamstring tendon. The patellar tendon attaches the bottom of the kneecap to the shin bone.

The cartilage within a healthy knee joint adds a cushioning effect between bones, enabling them to move smoothly without friction.

In contrast, in a knee suffering from arthritis (persistent wear and tear), the cartilage is worn away slowly over many years and doesn’t, leaving bone on bone, which is why this condition is so painful to endure.

Synovial fluid within the knee joint capsule provides lubrication all around the joint, aiding in movement and flexibility.

Common Knee Injuries

Knee pain and injuries typically cause physical discomfort and a restricted range of motion.

Some injuries keep you off your feet for months, which is so difficult for those used to active lifestyles.

The more common causes of knee pain are:

• Sprains
• Strains
• Ligament tears
• Muscle tears
• Fractures
• Wear and tear (knee arthritis)
• Knee dislocations
• Lumps, bumps, and tumors (less common)
• Cysts (for example – Bakers cyst)

Understanding how these conditions affect the knee can help individuals with severe pain acknowledge their symptoms.

Hopefully, this leads to them taking the best steps to get a proper diagnosis and treat the cause of pain.

Strains and sprains

Strains and sprains happen when muscles or ligaments in the knee become overstretched or torn.

Often these are caused by a sudden movement against the normal degree of leg mobility, such as twisting while running or jarring the knee during active exercise.

Symptoms frequently include swelling, bruising, tenderness, and pain on palpation at the injury site.

Treatment for strains and sprains involves lots of rest and limited physical activity for a few weeks, followed up by physical therapy to strengthen weakened muscles or ligaments.

Ligament tears

Tears or complete damage to ligaments in the knee joint cause immense pain and hypermobility.

Tears to the ACL (anterior cruciate ligament) or PCL (posterior cruciate ligament) are most frequently diagnosed in athletes, often leading to physical and psychological detrimental consequences.

My book covers the psychological effects of ACL injuries and more (do check it out here on Amazon)

Treatment for ligament injuries varies from conservative rest and renewal to cortisone injections for mild cases to reconstructive surgery for more severe tears.

Fractures

Fractures can happen anywhere in the knee, depending on the cause of injury.

Car accidents, bike falls, sports games and even tripping over a raised sidewalk and landing awkwardly are all causes of fractured knees.

Treatment again ranges from conservative options, such as the knee needing a cast/knee brace to support it while healing occurs, to surgery if the fracture needs metal plating (or other intervention with orthopedic surgeons involved.)

Osteoarthritis

Knee osteoarthritis is caused by repetitive wear and tear of the cartilage, although arthritis can also affect other joints in the body.

This cartilage breakdown leads to stiffness and discomfort when moving the knee joint.

It’s more commonly diagnosed amongst the elderly but also affects people at any age, depending on medical history/conditions/trauma sustained previously.

Treatments range from taking medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), which reduce inflammation & swelling, to lifestyle changes (weight loss & exercising regularly) to surgery.

Remember that every treatment plan is different for every knee injury.

It all depends on the healthcare team at the time, the individual, and the mechanism of injury too.

No matter what kind of injury you may or may not have suffered, it’s essential to seek medical advice if you have pain in your knee so that a correct diagnosis can be made.

Assessing Structures of the Knee

Diagnosing knee problems and understanding the cause of pain is essential for appropriate treatment.

Healthcare providers typically use imaging tests such as X-rays, Magnetic Resonance Imaging (MRI), Ultrasound, and CT scans to assess knee injuries.

Arthroscopy too is a minimally invasive procedure that allows direct visualization of the inside of your knee joint with tiny cameras inserted through small incisions on either side of your kneecap.

This procedure can identify small tears or minute damage to the ligaments within your knees and is often used for repairing them as well.

Use Of This Information

Of course, the best medicine is always prevention. This saying is well known and covers all aspects of our health, including our food and lifestyle choices.

It means – if we look after ourselves, our bodies will look after us.

Therefore, treating your knees carefully is crucial for maintaining knee health. Getting the right balance is key here.

So instead of hammering your knees daily by running on a hard tarmac road, try switching to a softer surface for half the week to give knees a well-earned break.

Perhaps consider less-impact sports too, such as swimming and cycling? These are fantastic for cardiovascular health and muscle strength combined.

And ensure you get adequate rest time too.

Our bodies aren’t machines – they are living organisms that need care and proper attention through food, relaxation, exercise, and downtime.

I hope you’ve found this post insightful. Consider these next if you’d like to read more of my posts. And thanks for reading!