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The knee joint

The knee joint

The knee is the largest and one of the most complex joints in the human body. It connects the thigh bone (femur) with the shin bone (tibia) and allows a wide range of movements that are essential in daily life, in sport and at work. It also carries the body’s weight and provides stability when standing, walking, running and jumping.

Function & biomechanics

The most complex joint in the human body

Function

The knee allows:

  • Flexion and extension (the main movement)
  • Rotation (when the knee is bent)
  • Sideways movement (only to a very limited degree)

This freedom of movement is essential for everyday activities such as running, climbing stairs or standing up.

Biomechanics

Load:

  • Standing: about 1× body weight
  • Walking: up to 5×
  • Jumping: up to 9×

Load distribution:

The menisci and cartilage distribute the pressure evenly.

Movement control:

The cruciate ligaments guide the rolling and gliding of the joint surfaces.

Kneecap mechanics:

The patella acts as a lever and increases muscle power during extension.

Health & prevention

The knee is susceptible to:

  • Osteoarthritis
  • Meniscus damage
  • Ligament injuries (for example a cruciate ligament tear)
  • Kneecap instability

Prevention:

  • Regular exercise
  • Strengthening the thigh muscles
  • Avoiding incorrect loading and excess weight
  • Good footwear and correct leg alignment during sport

In summary

The knee is a masterpiece of human anatomy and biomechanics. Keeping it healthy in the long term depends on movement, targeted training and having symptoms assessed early.

The team at Sportklinik Freiburg will be glad to help you with this.

Common causes of knee pain

Illustration of Anterior cruciate ligament tear
Conditions
Anterior cruciate ligament tear
A tear of the anterior cruciate ligament is one of the most common knee injuries – often painful, but very treatable.
Illustration of Meniscus injuries
Conditions
Meniscus injuries
Meniscus injuries are a common cause of knee complaints and can develop suddenly or gradually.
Illustration of Cartilage damage
Conditions
Cartilage damage
Cartilage damage in the knee often results from injury or wear and can cause severe pain.
Illustration of Patellar dislocation
Conditions
Patellar dislocation
In a patellar dislocation the kneecap slips out of its normal position and causes severe pain.
Illustration of Leg axis correction
Conditions
Leg axis correction
Leg axis correction is an effective option for younger patients who, despite progressive joint wear, do not yet need a replacement.
Illustration of Posterior cruciate ligament tear
Conditions
Posterior cruciate ligament tear
A posterior cruciate ligament tear is a rare but serious knee injury, often caused by heavy impact or accidents.
Illustration of Cruciate ligament re-rupture
Conditions
Cruciate ligament re-rupture
In a re-rupture the reconstructed ligament tears again, often after sporting activity.
Illustration of Knee osteoarthritis (gonarthrosis)
Conditions
Knee osteoarthritis (gonarthrosis)
Knee osteoarthritis is one of the most common joint conditions of all. It describes the progressive wear of the joint cartilage in the knee.

Our knee specialists

Experienced consultants caring for your knee health

Prof. Dr. med. Gerrit Bode

Prof. Dr. med. Gerrit Bode

Consultant in Orthopaedics and Trauma Surgery, additional qualification in specialist trauma surgery

Prof. Dr. med. Matthias Feucht

Prof. Dr. med. Matthias Feucht

Consultant in Orthopaedics and Sports Medicine

Dr. med. Friedrich Quarck

Dr. med. Friedrich Quarck

Consultant in Orthopaedics and Trauma Surgery

Dr. med. Ralph Mayer

Dr. med. Ralph Mayer

Consultant in Orthopaedics, specialist orthopaedic surgery