Kõõluste

Kõõõlused (singular kõõlus; genitive kõõluste) are fibrous connective tissues that attach muscles to bones, enabling movement by transmitting muscle force to skeletal elements. They are essential components of the musculoskeletal system and play a key role in locomotion and stabilization.

Structure and composition: Tendons consist mainly of tightly packed collagen fibers, predominantly type I collagen, aligned in parallel to resist tensile forces. They contain relatively few cells (fibroblasts) and a high extracellular matrix with water and proteoglycans. Many tendons have a protective covering, such as an epitenon or a paratenon, and some possess a synovial sheath to reduce friction during gliding.

Function and mechanics: Tendons function as transmitters of force, converting muscular contraction into movement at joints. They also act as elastic elements that store and release energy during dynamic activities, contributing to efficiency and speed. Their mechanical properties can adapt with training, increasing stiffness and tensile strength, while excessive or abrupt loading can lead to injury.

Healing and pathology: Tendons have relatively limited blood supply, especially in the mid-substance, which can slow healing after injury. Common tendon problems include tendinopathies and tears, often caused by overuse, aging, or improper loading. Symptoms typically include pain, tenderness, and reduced function. Diagnosis relies on clinical assessment and imaging such as ultrasound or MRI. Treatment is usually conservative: activity modification, physical therapy with eccentric loading, and analgesia. Corticosteroid injections may be used cautiously for short-term relief, and surgical repair is considered for refractory or severe tears.

Prevention and prognosis: Gradual progression of load, proper conditioning, and adequate recovery reduce risk. With appropriate rehabilitation, many tendon injuries heal and patients regain function, though recovery can be slow.