Polvinivellen

Polvinivellen is the knee joint in Finnish anatomical terminology. It is the largest synovial joint of the leg and a central site for weight bearing, movement, and load transfer during standing, walking, and running. The term polvinivellen is used in Finnish medical texts to refer to the knee joint in a general sense, and polvinivel or polvinivelen appear in more specific grammatical forms.

Anatomically, the knee consists of two articulations: the femorotibial joint, where the femur meets the tibia, and the patellofemoral joint, where the patella glides over the femur. The joint is surrounded by a fibrous capsule and lined with a synovial membrane. Articular cartilage covers the ends of the bones to reduce friction. The menisci (medial and lateral) act as shock absorbers and help stabilize the joint by distributing loads. Stability is provided by ligaments, including the cruciate ligaments (ACL and PCL) inside the joint capsule and the collateral ligaments (MCL and LCL) on the sides, as well as surrounding tendons and muscles such as the quadriceps, hamstrings, and the patellar tendon.

Movement is primarily flexion and extension, with small degrees of rotation when the knee is flexed. The knee relies on a balance of skeletal alignment, ligament integrity, and muscular control to maintain stability during dynamic activities.

Clinical relevance includes injuries such as ligament tears, meniscal injuries, and patellofemoral pain, as well as degenerative conditions like osteoarthritis. Diagnosis typically involves physical examination and imaging (X-ray or MRI). Treatment ranges from rest and physical therapy to injections or surgical procedures (arthroscopy, ligament reconstruction, or partial/total knee replacement) depending on severity and patient factors.