Skin Swelling and Soft Tissue Swelling: What It Means

What skin swelling means

Swelling happens when something adds volume to the skin or the tissue below it. The most common cause is edema, fluid that has leaked out of small blood vessels into the spaces between cells. Other causes are inflammation from an infection or injury, bleeding into the tissue (a bruise or hematoma), allergic reactions, and solid or fluid-filled lumps such as cysts.

Doctors describe swelling by its pattern:

• Localized: one area, such as a bite, a sprained wrist or an abscess.
• Generalized: both legs, the face and hands, or the whole body. This points to a body-wide problem.
• Pitting: pressing for 5 seconds leaves a dent. Typical of fluid edema.
• Non-pitting: firm swelling that does not dent, as in lymphedema, thyroid-related skin changes or angioedema.

For a detailed explanation of the types of skin edema and how they are treated, see the skin swelling condition guide.

What does "soft tissue swelling" mean?

"Soft tissue swelling" is a phrase radiologists often use on X-ray, ultrasound or MRI reports. Soft tissues are everything around the bone: skin, fat, muscle, tendons, ligaments and joint lining. The report means these tissues look thicker or puffier than normal.

It is a description, not a diagnosis. The cause is usually:

• a recent injury such as a sprain, strain or bruise
• inflammation of a tendon or joint lining (tendinitis, synovitis, arthritis)
• infection of the skin or deeper tissue
• a fluid collection such as a bursitis or cyst

Dorsal wrist soft tissue swelling

"Dorsal" means the back of the wrist, the side with the knuckles. Swelling here on an X-ray is common after a fall on the outstretched hand. It can hide a small fracture, especially of the triquetrum or scaphoid bones, or come from a wrist sprain or tendon inflammation. A soft, rounded swelling on the back of the wrist without injury is often a ganglion cyst. "Questionable" swelling on a report means the radiologist is unsure whether it is truly abnormal. Your doctor will match it to your symptoms and may repeat the X-ray in 10 to 14 days or order an MRI if pain persists.

Soft tissue swelling in the shoulder or other muscles

Swelling in a muscle usually follows a strain, a direct blow or heavy exercise. Less often it comes from infection, a blood collection, or a soft tissue lump. A muscle swelling that keeps growing, is larger than about 5 cm (2 inches), or is deep and firm should be scanned.

Causes of skin swelling by pattern

Medicines that cause swelling

Calcium channel blockers (such as amlodipine), steroids, NSAIDs, some diabetes medicines (pioglitazone), hormone therapy and some nerve-pain medicines can cause ankle swelling. ACE inhibitors can cause angioedema, even after years of use.

When to worry about skin swelling

Get help quickly for swelling that affects breathing or swallowing, swelling in one leg with pain, rapidly spreading red skin, or swelling after an injury with numbness or coldness of the limb. Generalized swelling that comes on over weeks also needs a check, because it can be the first sign of heart, kidney or liver disease.

A doctor will ask when the swelling started, whether it is one-sided, whether it itches or hurts, and about medicines, travel, injuries and other symptoms. They will press the swelling to check for pitting and look at the skin, joints and lymph nodes. Depending on the pattern, tests may include blood tests (kidney, liver, thyroid, albumin), a urine test for protein, a D-dimer or ultrasound for clots, an X-ray for injuries, or an echocardiogram for the heart.

Treatment and home care

Treat the cause. In the meantime:

• Injury: rest, ice wrapped in a cloth for 15 to 20 minutes every few hours in the first 48 hours, a compression bandage and elevation above heart level.
• Bites and mild allergy: a cold compress and a non-drowsy antihistamine, following the label.
• Leg swelling from standing or heat: raise your legs, walk regularly, and consider graduated compression stockings after checking with a doctor (they are unsafe with poor circulation).
• Cut back on salt if swelling is from fluid retention.
• Do not stop prescribed medicines that may cause swelling without speaking to your doctor first.

Infections need antibiotics, clots need anticoagulants, and heart, kidney or liver causes need specific treatment, sometimes with diuretics (water pills).

Frequently asked questions

What is skin swelling?

Skin swelling is enlargement or puffiness of the skin and the tissue under it. It is usually caused by fluid leaking from small blood vessels (edema), inflammation from injury or infection, an allergic reaction, or a lump under the skin. The pattern of the swelling points to the cause.

What does soft tissue swelling of the wrist mean?

It means the skin, fat, tendons or ligaments around the wrist bones look swollen on an X-ray or scan. It is usually from a sprain or bruise, but after a fall it can be the only sign of a small hidden fracture, so a follow-up X-ray or MRI may be advised if pain continues.

How do you treat soft tissue swelling in the wrist?

Rest the wrist, use ice for 15 to 20 minutes several times a day, keep it raised and use a wrist splint for support. Over-the-counter pain relievers help, following the label. If pain is near the base of the thumb, or does not improve within 1 to 2 weeks, ask for a repeat X-ray or MRI.

Is skin edema serious?

Mild edema from heat, long sitting or a minor injury is not serious. Edema of both legs that persists, swelling of the face and throat, or swelling of one leg with pain can be serious and needs medical assessment.

How can I tell swelling from fat?

Swelling usually comes on over days or weeks, may leave a dent when pressed, and often varies through the day. Fat is soft, even, painless and does not change from morning to evening. Lipedema, a fat disorder in the legs, is an exception that can be tender and needs a doctor's assessment.