Patellar Tendinopathy (Jumper's Knee)
Summary
Patellar tendinopathy, commonly known as Jumper's Knee, is an overuse injury affecting the patellar tendon, typically at its insertion on the inferior pole of the patella. It is common in athletes involved in jumping sports (basketball, volleyball) and running. The pathology involves degenerative changes (tendinosis) rather than inflammation, hence "tendinopathy" is the preferred term over "tendonitis". Patients present with anterior knee pain localised to the inferior patellar pole, worsened by jumping, squatting, and prolonged sitting. Treatment is primarily conservative, with eccentric loading exercises (decline squats) being the gold standard. Steroid injections are contraindicated due to rupture risk.
Key Facts
- Definition: Overuse tendinopathy of patellar tendon (inferior pole attachment)
- Demographics: Jumping athletes (basketball, volleyball), Runners
- Pathology: Tendinosis (degenerative, not inflammatory)
- Symptoms: Anterior knee pain at inferior patella, worse with jumping
- Treatment: Eccentric exercises (decline squats) — Gold standard
- Avoid: Steroid injections (rupture risk)
Clinical Pearls
"Tendinopathy, Not Tendonitis": The pathology is degenerative (tendinosis), not inflammatory.
"Decline Squats = Gold Standard": Single-leg decline squat eccentric loading is the most evidence-based treatment.
"No Steroids!": Corticosteroid injections are contraindicated — they increase rupture risk.
"Chronic and Frustrating": Patellar tendinopathy is notoriously slow to heal and prone to recurrence.
Incidence
- 14% of elite basketball players
- 45% of elite volleyball players
Demographics
- Peak: 15-30 years
- M > F
- Jumping athletes (basketball, volleyball, high jump)
- Runners
Risk Factors
| Factor | Notes |
|---|---|
| Jumping sports | High repetitive load |
| Increased training load | Too much, too soon |
| Poor lower limb biomechanics | Reduced ankle dorsiflexion, Hip weakness |
| Hard surfaces | |
| Obesity | Increased tendon load |
Tendinosis (Not Tendonitis)
- Collagen disorganisation
- Increased ground substance (mucoid degeneration)
- Neovascularisation (abnormal blood vessel ingrowth)
- Absence of inflammatory cells (hence not "tendonitis")
Location
- Most commonly at inferior pole of patella (proximal tendon insertion)
- Less commonly mid-tendon or tibial tubercle attachment
Failed Healing Response
- Repeated microtrauma
- Tendon unable to fully heal before next loading cycle
- Progressive degeneration
Symptoms
| Feature | Description |
|---|---|
| Pain | Anterior knee, localised to inferior patellar pole |
| Onset | Gradual, activity-related |
| Worse with | Jumping, Squatting, Stairs, Prolonged sitting ("movie sign") |
| Stiffness | Morning or after rest |
Severity Staging (Blazina Classification)
| Stage | Symptoms |
|---|---|
| 1 | Pain only after activity |
| 2 | Pain during and after activity, but able to perform |
| 3 | Pain during and after, affecting performance |
| 4 | Complete tendon rupture |
Inspection
- May appear normal
- Swelling at inferior pole (sometimes)
Palpation
- Localised tenderness at inferior pole of patella
- Tenderness reproduced with knee in extension
Functional Tests
- Pain with single-leg squat
- Pain with jumping
Imaging
| Modality | Findings |
|---|---|
| Ultrasound | Tendon thickening, Hypoechoic regions, Neovascularisation (Doppler) |
| MRI | Thickened tendon, Increased signal, Peritendinous oedema |
| X-ray | Usually normal; May show calcification or patella alta (if rupture) |
VISA-P Score
- Validated outcome measure for patellar tendinopathy
- Assesses pain and function
Treatment Approach
┌──────────────────────────────────────────────────────────┐
│ PATELLAR TENDINOPATHY MANAGEMENT │
├──────────────────────────────────────────────────────────┤
│ │
│ FIRST-LINE: ECCENTRIC LOADING │
│ • Single-leg decline squat protocol │
│ - 25° decline board │
│ - 3 sets x 15 reps, twice daily │
│ - 12-week programme │
│ • Evidence: Best long-term outcomes │
│ │
│ ADJUNCTIVE: │
│ • Load management (reduce jumping/training volume) │
│ • Isometric exercises (for pain relief) │
│ • Patellar tendon strap (offloading) │
│ • Ice after activity │
│ • NSAIDs (short-term, but don't address pathology) │
│ │
│ SECOND-LINE (IF CONSERVATIVE FAILS): │
│ • Extracorporeal Shockwave Therapy (ESWT) │
│ • PRP injections (mixed evidence) │
│ • High-volume injection (strips neovessels) │
│ │
│ ⚠️ CONTRAINDICATED: │
│ • Corticosteroid injections (risk of rupture) │
│ │
│ SURGICAL (RARE): │
│ • Arthroscopic or open debridement │
│ • Reserved for refractory cases (>6-12 months) │
│ │
└──────────────────────────────────────────────────────────┘
Of Condition
- Chronic pain and disability
- Tendon rupture (rare, but increased with steroids)
- Career-ending in elite athletes
Of Treatment
- PRP: Infection, Pain, No guaranteed benefit
- Surgery: Stiffness, Infection, Prolonged recovery
With Eccentric Loading
- 70-80% improvement at 12 weeks
- Requires compliance
Elite Athletes
- Often prolonged recovery
- May require season modification
Poor Prognostic Factors
- Long symptom duration before treatment
- Severe neovascularisation
- Previous steroid injection
Key Resources
- VISA-P Score: Validated outcome measure
Key Evidence
Eccentric Loading
- RCT evidence supports decline squat protocol
PRP
- Mixed evidence; May help in selected cases
What is Jumper's Knee?
Jumper's knee is a painful condition affecting the tendon that connects your kneecap to your shinbone. It's caused by overuse, especially in sports involving jumping.
What Causes It?
Repeated stress on the tendon (from jumping, running, or squatting) causes small tears that don't fully heal, leading to pain and weakness.
What Are the Symptoms?
- Pain at the front of the knee, just below the kneecap
- Worse with jumping, squatting, or stairs
- Stiffness after sitting for a long time
How is It Treated?
- Exercises: Special "eccentric" exercises (decline squats) are the main treatment
- Rest from aggravating activities: Reduce jumping and high-impact sports
- Avoid steroid injections: These can weaken the tendon
Will It Get Better?
Yes, but it takes time — often 3-6 months of consistent exercise. Some athletes need longer to fully recover.
Primary Resources
- Malliaras P, et al. Patellar tendinopathy: clinical diagnosis, load management, and practical rehabilitation. J Orthop Sports Phys Ther. 2015;45(11):887-898. PMID: 26381484
Key Studies
- Kongsgaard M, et al. Eccentric training increases collagen synthesis rate in Achilles tendinosis. Am J Physiol Regul Integr Comp Physiol. 2007;293(4):R1235-R1242. PMID: 17609315