In plain language
A fluid-filled swelling behind the knee, often associated with intra-articular disease in adults.
Clinical Significance & Management
No. A ruptured cyst and deep vein thrombosis can look similar and need prompt assessment, often ultrasound. Chest pain, breathlessness or fainting requires emergency help. Avoid massage or continued exercise.
Symptoms & Clinical Presentation
Posterior fullness or movement discomfort; sometimes no symptoms
Etiology & Injury Mechanisms
- Excess joint fluid, often with arthritis or meniscal disease
Diagnostics & Imaging Guide
Examination and ultrasound; MRI for intra-articular issues if needed
Treatment Options
Observe or treat underlying disease; selective aspiration or other treatment
Rehabilitation Milestones & Timeline
Rehabilitation depends on the diagnosis, procedure and associated injuries. Progression requires assessment of healing, symptoms and function; elapsed time or a single test cannot determine readiness for sport.
Progressive rehabilitation
Restore motion and strength according to knee symptoms
Evidence-Based Clarifications
Recurrence after aspiration may reflect persistent joint fluid production.
Sources & References
Educational clinical definitions synthesized from AAOS, Cleveland Clinic, Mayo Clinic, and HSS. Individual diagnosis and surgery require professional medical evaluation.
Publication date
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