Caused by increased tension and pressure due to repetitive traction by the patellar tendon on the lower pole of the patella (still partly cartilaginous in adolescents) during contraction of the quadriceps muscle. This leads to cartilage damage, swelling and pain, especially after exertion of force, and later to tendon thickening and fragmentation of the lower pole of the patella and sometimes to bursitis, i.e. inflammation of a bursa situated between the tendon and the patella.
The syndrome is seen in adolescents typically between 10 and 14 years of age, but most often in males who play sports (football, running, volley ball, gymnastics)
- Clinically it is characterized by pain, which increases when the patellar is loaded during flexion, subpatellar swelling and functional limitation.
- Pain localized to the lower pole of the patella
Ultrasound (USG):Can depict all the manifestations of this disorder
- Swelling of the cartilage
- Tendon thickening
- Fragmentation of the lower pole of the patella
- Osgood-Schlatter disease (OSD)
- Patellar sleeve avulsion (PSA) fractures
Therapy is mainly rest and abstention from sports activity for at least 1–2 months, particularly football and running that may be replaced by swimming and other sports which exert less pressure on the quadriceps femoris muscle. The evolution is usually benign with spontaneous recovery; thanks to the physiological regeneration full recovery usually takes 12–24 months. When the patella is completely ossified the pain disappears and complications are rare