Which of the following, among axillary lymph nodes, is a terminal group –
**Core Concept**
Axillary lymph nodes play a crucial role in the drainage of the upper limb, breast, and chest wall. The axillary lymph nodes are divided into three groups: pectoral (anterior), apical, and posterior. The terminal group of axillary lymph nodes refers to those that drain into the subclavian lymphatic trunk.
**Why the Correct Answer is Right**
The apical group of axillary lymph nodes is considered the terminal group because they are the last station for lymphatic drainage from the upper limb and breast before it enters the subclavian lymphatic trunk. This group is located at the apex of the axilla and receives lymph from the other two groups. The apical lymph nodes then drain into the subclavian lymphatic trunk, which ultimately empties into the jugulosubclavian junction.
**Why Each Wrong Option is Incorrect**
* **Option A:** The pectoral group is not the terminal group as it primarily receives lymph from the anterior chest wall and breast. Although it is an important group, it does not drain into the subclavian lymphatic trunk.
* **Option B:** The lateral group is not a distinct group of axillary lymph nodes. Instead, it is a collection of lymph nodes that are scattered throughout the axilla and do not form a distinct group.
* **Option D:** The subclavian lymphatic trunk is not an axillary lymph node group but rather a lymphatic trunk that receives lymph from the axillary and other lymph nodes before emptying into the jugulosubclavian junction.
**Clinical Pearl / High-Yield Fact**
When performing axillary dissection or biopsy, it is essential to identify the apical group of axillary lymph nodes as they are a common site for metastatic disease in breast cancer.
**Correct Answer: C. Apical group**