Physical Examination Description of Lipoma
A lipoma on physical exam should be described as a soft, mobile, well-circumscribed subcutaneous mass with a characteristic "doughy" consistency that moves easily under palpation. 1
Essential Physical Characteristics to Document
Texture and Consistency
- Soft and doughy feel is the hallmark characteristic that distinguishes lipomas from other masses 1
- The mass should be rubbery and compressible under palpation 2
- Note whether the lesion demonstrates the "pillow sign" (indentation when pressed with fingers or instruments), which has 98% specificity for lipoma 3
Mobility and Borders
- Mobile and freely movable beneath the skin, not fixed to underlying structures 1
- Well-defined, smooth margins that are easily palpable 1, 4
- The mass should move independently of the overlying skin 2
Size and Shape
- Document exact measurements in centimeters (length, width, depth if palpable) 5
- Most lipomas are small (less than a few inches), but note that masses >5 cm require additional evaluation 6, 7
- Lipomas are typically elongated with their greatest diameter parallel to the skin surface 4
Pain and Tenderness
- Lipomas are typically painless and non-tender on palpation 1
- Any tenderness or pain is atypical and warrants further investigation 6, 7
Location
- Document the anatomic location precisely (most commonly neck, shoulders, back, abdomen, arms, or thighs) 1
- Note whether the mass is superficial (subcutaneous) or deep-seated, as deep location raises concern for atypical lipomatous tumor 6, 3
Critical Red Flags Requiring Advanced Evaluation
Document and escalate if any of the following are present:
- Size >5 cm (giant lipoma or possible malignancy) 6, 7, 5
- Rapid growth or recent change in size 6, 7
- Pain or tenderness (atypical for benign lipoma) 6, 7
- Fixed or immobile mass (suggests deeper involvement) 1
- Firm or hard consistency (inconsistent with lipoma) 1
- Deep-seated location, especially in lower limb (higher risk of atypical lipomatous tumor) 6
Important Clinical Pitfalls
- Physical examination alone is only 85% accurate for diagnosing lipomas, so imaging confirmation is important for atypical presentations 3
- Do not rely solely on clinical impression for masses with any red flag features—these require ultrasound at minimum 6, 3
- A palpable mass that feels like a lipoma but is painful, growing, or >5 cm mandates imaging (ultrasound first, then MRI if concerning features) 6, 7