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Please ask a qualified health professional about symptoms, treatment decisions, or concerns about your own condition.
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Bones & Joints
Patellar tendinitis (jumper's knee) is an overuse injury causing pain at the bottom of the kneecap where the patellar tendon attaches, most commonly affecting jumping athletes (basketball, volleyball, netball players) due to repetitive stress during landing and takeoff. The condition develops from accumulated microtrauma to the tendon causing degenerative changes (tendinosis—collagen breakdown and failed healing) rather than acute inflammation, presenting as anterior knee pain that worsens with jumping, running, squatting, or stairs and is tender to touch just below the kneecap. Patellar tendinopathy progresses through stages from pain only after activity (Stage 1) to constant pain affecting sport performance (Stage 3-4), classified by the Blazina system. Treatment focuses on load management and eccentric strengthening exercises (heavy slow resistance training shown to stimulate tendon remodeling), with 70-80% achieving good results over 3-6 months of conservative management, though 10-20% develop chronic symptoms requiring surgical intervention (debridement or tendon scraping) for refractory cases not responding to 6-12 months of physiotherapy.
What it is and why it happens
Patellar tendinitis (jumper's knee) is an overuse injury causing pain at the bottom of the kneecap where the patellar tendon attaches, most commonly affecting jumping athletes (basketball, volleyball, netball players) due to repetitive stress during landing and takeoff. The condition develops from accumulated microtrauma to the tendon causing degenerative changes (tendinosis—collagen breakdown and failed healing) rather than acute inflammation, presenting as anterior knee pain that worsens with jumping, running, squatting, or stairs and is tender to touch just below the kneecap. Patellar tendinopathy progresses through stages from pain only after activity (Stage 1) to constant pain affecting sport performance (Stage 3-4), classified by the Blazina system. Treatment focuses on load management and eccentric strengthening exercises (heavy slow resistance training shown to stimulate tendon remodeling), with 70-80% achieving good results over 3-6 months of conservative management, though 10-20% develop chronic symptoms requiring surgical intervention (debridement or tendon scraping) for refractory cases not responding to 6-12 months of physiotherapy.