Knee Bursae: A Comprehensive Review of Clinical Evaluation, Imaging Differentiation, and the Expanding Role of Biologic Therapies.

In 30 seconds

This PRISMA-guided systematic review examined anatomy, presentation, imaging, treatment, and outcomes across 11 knee bursae, drawing on 76 human studies published in English from 2000 to 2024. Evidence quality varied by bursal type: randomized trials were available mainly for pes anserine and osteoarthritis-related bursitis, whereas rare bursae were represented largely by imaging reviews and case series. Corticosteroid injections were associated with recurrence rates of 20% to 40%. Platelet-rich plasma, alone or with hyaluronic acid, showed improved pain relief and reduced recurrence in selected bursae, but treatment protocols were heterogeneous.

Key findings

• Corticosteroid injections had reported recurrence rates of 20% to 40%.
• PRP and PRP+HA showed improved pain relief and reduced recurrence in selected bursae, with heterogeneous protocols.
• Evidence for rare bursae, including LCL and deep infrapatellar bursae, was primarily from Level III-IV imaging reviews and case series.

Why it matters

Recognizing bursae as potential sources of pain across several knee regions may support more targeted evaluation and imaging differentiation. The review also indicates that treatment evidence is uneven: biologic approaches appear promising for selected refractory cases, but findings should be interpreted in light of heterogeneous protocols and limited evidence for less-studied bursae.

What to keep in mind

Evidence was limited for several bursal types, with rare bursae represented mainly by imaging reviews and case series; PRP protocols were heterogeneous.