LYMPH•LOGISCH · Understand your symptoms
Seroma: a fluid pocket after surgery.
A localised fluid pocket can develop after different operations, including breast surgery, plastic surgery or hip replacement. Learn how a seroma differs from tissue swelling, when monitoring may be enough and when the surgical team should reassess it.
What is a seroma and why does it develop?
Surgery divides small blood and lymph vessels and separates tissue layers. Wound fluid can collect in the resulting space, forming a seroma. Seromas can follow breast and lymph node surgery, plastic surgery and orthopaedic procedures such as hip or knee replacement. After breast surgery the pocket may lie around the operation site or armpit. Unlike diffuse tissue swelling, the fluid is contained in a localised pocket. Both can occur together. [1], [5] [7]
What matters after hip or knee replacement?
A hip replacement, also called a total hip arthroplasty, can be followed by a seroma. A haematoma or infection may look similar. Especially near a prosthesis, a new or increasing fluid collection needs assessment by the surgical team. Ultrasound can help locate it, but cannot reliably exclude infection on its own. Whether observation, aspiration or another treatment is appropriate depends on the findings. [7]
Can it settle on its own?
Yes. As small vessels and tissue layers heal, less fluid may enter the space and the body can gradually absorb the collection. Small seromas causing little discomfort often settle within several weeks. Others take longer or refill. Size alone does not determine treatment: symptoms, wound healing and progress also matter. [1]
When is aspiration appropriate?
If a seroma causes substantial tightness, pain or restricted movement, the treating team may recommend aspiration. A needle is used under sterile conditions to withdraw fluid. This can relieve pressure but does not always stop the pocket refilling, so repeat aspirations may be needed. Small collections causing little discomfort are not automatically aspirated because the procedure carries risks such as infection and bleeding. With an implant, the surgical team weighs the risks carefully; ultrasound guidance can help protect the implant during aspiration. Assessment and aspiration belong with the treating surgical team. [1], [4] [6]
How can physiotherapy contribute?
Physiotherapy supports movement and function of the affected region and addresses symptoms in surrounding tissue. Depending on the operation, this may involve the shoulder and arm or walking and hip or knee movement. You receive exercises adapted to wound healing and surgical instructions. Any additional tissue swelling or lymphoedema is assessed and treated separately. An established seroma is not treated in the same way as lymphoedema: convincing evidence that manual lymphatic drainage clears the pocket or avoids aspiration is currently lacking. Forceful pressure or trying to massage the pocket away is not the treatment goal. [2]
When should the surgical team reassess it?
Redness, warmth, fever, increasing pain, rapid enlargement or leaking wound fluid need prompt medical review. A repeatedly recurring seroma also needs reassessment. Persistent cases may require discussion of further drainage or surgical options. Refilling does not automatically mean another operation is necessary. [1], [5]
Research in context
What do the studies show?
How do physiotherapy and seroma care complement each other?
A controlled study of 89 women compared drainage with active exercise after breast cancer and lymph node surgery. Seroma frequency and aspiration numbers did not differ clearly. The non-randomised study concerned early aftercare rather than targeted treatment of established seromas. The roles are important: the collection needs medical assessment, while physiotherapy may address permitted movement and accompanying symptoms. Aspiration findings do not describe every aim of postoperative care. [2]
What does newer research add?
A 2025 meta-analysis, collected in a 2026 issue, concerns prevention after breast surgery: surgical techniques that secure tissue layers showed benefits. It does not answer how physiotherapy should treat an existing seroma. [3] A large 2026 observational study found an association between aspiration and uncommon later bleeding, especially with antithrombotic medication. This supports careful individual decisions, not avoiding medically needed aspiration. Do not stop prescribed medication yourself. [4]
What is known after joint replacement?
A 2022 narrative review addresses fluid collections after hip and knee replacement. It emphasises distinguishing seroma, haematoma and infection and describes limited evidence for treatment choices. It does not establish that lymphatic drainage resolves a seroma. [7]
Different roles, a shared aim.
With a seroma, I think it is important to keep professional roles clear. Your medical team decides whether observation, aspiration or another measure is needed. In physiotherapy, we can address accompanying symptoms and movement in the affected area. This keeps treatment focused on what it can appropriately contribute.
Studies and clinical sources
- Royal Berkshire NHS (2026)
Patient information on formation, natural course and aspiration of seromas after breast surgery
- de Oliveira et al. (2014)
Controlled non-randomised trial in 89 women: drainage versus active exercises, not a trial treating an established seroma
- Makhseed et al. (2025, Ausgabe 2026)
Systematic review and meta-analysis of 34 studies on prevention, not physiotherapy treatment of established seromas
- Tamminen et al. (2026)
Retrospective cohort of 2,710 mastectomies: bleeding complications associated with aspiration, not a randomised trial
- Papanikolaou et al. (2022)
Retrospective study of 156 seromas needing treatment after varied operations, including many difficult cases
- UCLA Health: Post-Surgical Fluid Collections
Clinical breast-imaging guidance on observation, aspiration and implant protection
- Smith et al. (2022): Postoperative Fluid Collections in Total Joint Arthroplasty
Narrative review of fluid collections after hip and knee replacement, differential diagnosis and management; not a trial of lymphatic drainage
Reviewed: 16 October 2026. A selection of relevant sources, not a systematic review. Information cannot establish a diagnosis or replace an individual assessment.