Knee injuries

Knee injuries are among the most common sporrts injuries. Due to the importance of the knee joint for our function, daily- and sports activities knee injuries should be evaluated by a specialised knee surgeon.


Dependent on the sport performed and the mechanism of injury a variety of different injuries of ligaments, menisci, cartilage or bone are present. In the following you find a review of the most common ones.


Tear of anterior or posterior cruciate ligament

A tear of the anterior cruciate ligament (ACL) is a common sports injury. About 3000 patients have to undergo surgery in Switzerland each year.


Typical symptoms of a torn ACL are an unstable feeling and giving way symptoms. The knee feels to give way in daily and sport activities.

Due to the instability of the knee a significant number of patients suffers then from additional lesions of the meniscus or cartilage. Hence, patients who like to do pivoting sports, an ACL reconstruction is indicated. 


A considerable number of ACL injuries are not isolated, meaning there are associated lesions of other structures. Most frequently the medial collateral ligament, menisci or the cartilage is affected.These should always be addressed in surgery. Here it is important to restore as much meniscus as possible.

In particular the state of the meniscus and cartilage is a good predictor for OA after ACL injury, whether reconstructed or not.


A tear of the posterior cruciate ligament (PCL) is rare when compared to ACL injuries. PCL tears can be treated non-surgical in sedentary patients and in the case of isolated lesions. An arthroscopic reconstruction of the PCL is indicated when there is a persistent instability and in patients who ambitously undergo sports.


Tears of medial or lateral collateral ligament

Generally injuries of the medial collateral ligament can be treated non surgically. However, in the case of a bony avulsion or a more complex knee injury a surgical reconstruction or repair is indicated. It can also become necessary after insufficent healing in a non-surgical treated knee.


Injuries of the lateral collateral ligament should be treated early by repair or reconstruction of the ligament. Generally in these cases a more complex knee injury is present, meaning more ligaments, the meniscus or cartilage is affected. 


Meniscal injuries

Meniscal lesions are among the most common injuries of the knee. These can occur during sports injuries (traumatic) and due to degenerative changes in daily activites without a clear trauma.


It is decisive for an optimal treatment to assess the type, size, course and quality of each meniscal lesion.

Generally as much meniscus tissue as possible should be  preserved as it is a significant shock absorber for the knee.


Mechanically unstable tears of the meniscus need to be treated surgically. A suture of the meniscus can be successfully performed if the meniscus tissue is of sufficient quality. The tear of the meniscus should not be older than 3 weeks.

If this is not the case a careful partial resection (partial meniscectomy) of the torn meniscus should be done.


In the image here you can see a torn medial meniscus seen during arthroscopy.


After partial or subtotal meniscectomy in young or older sportive patients with no osteoarthritis a meniscal substitution or transplantation should be discussed.


Cartilage injuries

Focal cartilage defects have to be differentiated from osteoarthrits, which typically affects the whole knee joint.


Cartilage lesions vary in size and depth as well as the quality of the remaining cartilage. One has to distinguish between a pure cartilage from an osteochondral lesion.


For treatment of such cartilage lesions a variety of differtent treatment options are available. These range from microfracturing, over cell free collagen membrane associated procedures (MACI) to autologous chondrocyte transplantation (ACT). In case of an osteocondral lesion an osteochondral repair surgery is performed.


Patella dislocation

Numerous causes can be attributed for a patellar dislocation. A traumatic (trauma related) can be distinguished from a non-traumatic (dysplastic) patellar instability.


Typically the knee cap dislocates externally out of the trochlear groove. In this case the patient suffers from heavy knee pain. Reduction of the knee cap occurs when the knee is brought into extension.


A dislocation of the knee cap might cause tear of the medial patellofemoral ligament, cartilage lesions or osteochondral fractures. Hence, it is important to undergo extensive diagnostics including clinical examination, radiographs and MRI.


Treatment depends on the cause of patellofemoral instability, the injury pattern and associated lesions. 



Sport injuries can lead to breaking of different bones.


The most commonly fractured bones are the shin bone and the ankle joint. Ins some cases of heavy trauma the tibial plateau can break.