Treatment of Infrapatellar Bursitis in a Teenager
Initial treatment should consist of scheduled NSAIDs combined with activity modification, ice, and rest, as this conservative approach effectively manages most cases of infrapatellar bursitis in adolescents. 1, 2
Initial Conservative Management
Start with scheduled NSAIDs as first-line therapy, which provide both analgesic and anti-inflammatory effects. 1, 3 For teenagers, naproxen is an appropriate choice at approximately 10 mg/kg/day divided into two doses (5 mg/kg twice daily), though the specific dosing for acute bursitis is 500 mg initially, followed by 250 mg every 6-8 hours as needed. 3
Adjunctive Conservative Measures
- Apply ice, elevation, and rest to the affected knee, particularly in the acute phase. 2, 4
- Modify activities that involve repetitive kneeling or direct pressure on the infrapatellar region, as chronic microtrauma is the most common cause of superficial bursitis. 2
- Consider compression to reduce swelling and provide support. 4
Physical Therapy Considerations
Physical therapy is conditionally recommended for teenagers who have or are at risk for functional limitations, focusing on maintaining range of motion and strengthening periarticular muscles. 1, 5 This is particularly important if the bursitis is limiting mobility or athletic participation.
When to Escalate Treatment
Rule Out Underlying Inflammatory Conditions
Be vigilant for signs of juvenile idiopathic arthritis (JIA), as infrapatellar bursitis can occur as an isolated finding or concurrently with knee joint synovitis in JIA patients. 6 Red flags include:
- Multiple joint involvement
- Morning stiffness
- Systemic symptoms (fever, fatigue)
- Persistent symptoms despite conservative treatment 7
If JIA with enthesitis is suspected, NSAIDs remain first-line, but TNF inhibitors are conditionally recommended over methotrexate or sulfasalazine for persistent symptoms despite NSAIDs. 1, 5
Corticosteroid Options for Refractory Cases
For bursitis persisting despite 2-4 weeks of NSAIDs and conservative measures, consider:
- Direct corticosteroid injection into the deep infrapatellar bursa may be needed, as this bursa does not communicate with the knee joint. 6 Two cases in the literature showed complete resolution with targeted bursal injections. 6
- A limited course of oral glucocorticoids (<3 months) can be used as bridging therapy, particularly with high disease activity or significant functional limitation. 1, 7
Diagnostic Imaging When Indicated
MRI should be obtained if:
- Clinical suspicion for concurrent knee joint synovitis exists
- Diagnosis is uncertain
- Symptoms persist despite appropriate conservative treatment 6
MRI can confirm the diagnosis, detect concurrent pathology, and guide targeted treatment (such as distinguishing isolated bursitis from combined synovitis). 6
Critical Pitfalls to Avoid
Do not aspirate microtraumatic bursitis routinely, as this increases the risk of iatrogenic septic bursitis. 2 Aspiration is reserved for:
- Suspected septic bursitis (perform Gram stain, culture, cell count, crystal analysis)
- Acute traumatic/hemorrhagic bursitis where aspiration may shorten symptom duration 2
Avoid intrabursal corticosteroid injections as routine first-line treatment, as high-quality evidence demonstrating benefit for microtraumatic bursitis is unavailable. 2 Reserve this for refractory cases or when underlying inflammatory arthritis is present.
Do not dismiss insidious onset knee pain as simple overuse without ruling out inflammatory arthritis, as early DMARD therapy is crucial for JIA to prevent permanent joint damage. 7
Avoid prolonged oral glucocorticoids as monotherapy—they should only be used for short-term bridging (<3 months) during initiation of other therapies. 7, 1
Treatment Timeline
- Evaluate response after 2-4 weeks of conservative management with NSAIDs. 2, 4
- If no improvement by 6-8 weeks, consider imaging, rheumatology referral, or escalation to corticosteroid injection. 6, 8
- Chronic or recurrent cases may ultimately require surgical excision of the bursa, though this is rarely needed in teenagers. 8, 9