Which is not a feature of pilonidal sinus?
**Core Concept**
Pilonidal sinus is a chronic, painful skin condition characterized by a small, usually infected, cyst or abscess in the natal cleft of the buttocks. It is often associated with hair follicles and can lead to significant morbidity if not treated properly.
**Why the Correct Answer is Right**
The correct answer is a feature of pilonidal sinus because it is a common presentation of the condition. Pilonidal sinus often presents with a tender, fluctuant mass in the natal cleft, which may be associated with a sinus tract or multiple tracts. This can be accompanied by symptoms such as pain, swelling, and discharge.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option may be incorrect because pilonidal sinus is not typically associated with a palpable mass in the inguinal region.
* **Option B:** This option may be incorrect because pilonidal sinus is not typically associated with a history of trauma to the genital area.
* **Option C:** This option may be incorrect because pilonidal sinus is not typically associated with a painful, swollen scrotum.
**Clinical Pearl / High-Yield Fact**
Pilonidal sinus is often associated with a "tail of hair" or a tuft of hair protruding from the sinus tract, which can be a diagnostic clue. This is due to the hair follicle being a common site for the development of the pilonidal sinus.
**Correct Answer: C. A painful, swollen scrotum.**