A patient presents with the skin lesion shown in the image. Based on the characteristic color changes, what is the approximate age of this contusion?

Explanation

## Image Findings * An area of skin discoloration (contusion/bruise) is visible, partially covered by dark blue clothing. * The predominant color of the lesion is **yellowish-green**. * Scattered, smaller, darker purplish-red spots are interspersed within the yellowish-green area. * The skin surface appears intact, without any open wounds or significant swelling. ## Diagnosis **Key Point:** The yellowish-green discoloration of the contusion indicates an approximate age of **5-10 days old**. Bruises undergo characteristic color changes over time due to the enzymatic breakdown of hemoglobin. Initially, extravasated blood appears reddish (due to oxygenated hemoglobin) or bluish-purple (due to deoxygenated hemoglobin). As hemoglobin is metabolized, it is converted to **biliverdin**, which imparts a **green** hue. Subsequently, biliverdin is converted to **bilirubin**, resulting in a **yellow** color. The presence of both green and yellow pigments, creating a distinct yellowish-green appearance, signifies that the bruise is in the later stages of this breakdown process, typically occurring between 5 to 10 days after the injury. ## Differential Diagnosis | Feature | 0-1 day old bruise | 2-3 days old bruise | 5-10 days old bruise (Image) | More than 2 weeks old bruise | | :------------------ | :---------------------- | :---------------------- | :--------------------------- | :--------------------------- | | **Color** | Reddish, bluish-purple | Bluish-purple, greenish | **Yellowish-green** | Faded, brownish, or resolved | | **Hemoglobin state**| Oxygenated/Deoxygenated | Deoxygenated/Biliverdin | **Biliverdin/Bilirubin** | Hemosiderin/Resolution | | **Clinical appearance** | Fresh, tender, swollen | Distinctly discolored | Fading, less tender | Barely visible or gone | ## Clinical Relevance **Clinical Pearl:** Estimating the age of a bruise is crucial in forensic medicine, especially in cases of suspected child abuse, elder abuse, or assault, to correlate injuries with reported events. ## High-Yield for NEET PG **High-Yield:** The sequence of color changes in a bruise is a classic forensic indicator: Red/Blue/Purple (0-5 days) → Green (5-7 days) → Yellow (7-10 days) → Brown/Fading (10-14+ days). **Key Point:** The color changes are due to the breakdown products of hemoglobin: Hemoglobin → Biliverdin (green) → Bilirubin (yellow) → Hemosiderin (golden-brown). ## Common Traps **Warning:** Factors like skin tone, depth of injury, location of the bruise, and individual healing rates can influence the exact timing and intensity of color changes, making precise dating challenging. However, the general sequence remains consistent. ## Reference [cite:Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology, Ch 12]