The intertubercular groove is a shallow groove on the anterior surface of the proximal humerus. It is located between the greater and lesser tubercles, which are the sites of insertion for the supraspinatus and infraspinatus muscles, respectively. The intertubercular groove runs obliquely from the greater tubercle to the lesser tubercle, and it provides a passage for the long head of the biceps brachii tendon. The intertubercular groove is also related to the pectoralis major muscle, which inserts onto the greater tubercle, and the coracobrachialis muscle, which inserts onto the lesser tubercle.
Structure of the Intertubercular Groove of the Humerus
The intertubercular groove of the humerus is a deep, narrow groove located on the anterior surface of the proximal humerus, between the greater and lesser tubercles. It runs obliquely from the lateral to the medial side of the proximal humerus and is bounded by the medial and lateral lips of the groove. Here’s a more detailed breakdown of its structure:
1. Shape and Dimensions:
- The intertubercular groove is typically narrow and V-shaped in cross-section.
- It is approximately 2-3 cm in length and 0.5-1 cm in width.
2. Boundaries:
- Medial Lip: The medial lip is formed by the medial margin of the greater tubercle and the medial surface of the proximal humerus.
- Lateral Lip: The lateral lip is formed by the lateral margin of the lesser tubercle and the lateral surface of the proximal humerus.
3. Surface Features:
- The floor of the groove is smooth and slightly concave.
- It contains multiple foramina (small openings) for the passage of nutrient arteries and veins.
4. Muscles and Tendons:
- The intertubercular groove provides a passageway for the tendons of the following muscles:
- Subscapularis muscle: Inserts into the lesser tubercle.
- Supraspinatus muscle: Inserts into the greater tubercle.
- Infraspinatus muscle: Inserts into the greater tubercle.
- Teres minor muscle: Inserts into the greater tubercle.
5. Clinical Significance:
- The intertubercular groove is a common site for entrapment of the long head of the biceps tendon, a condition known as biceps tendinitis.
- Fractures involving the intertubercular groove can damage the tendons passing through it, leading to shoulder dysfunction.
Table Summarizing the Structure:
| Feature | Description |
|---|---|
| Shape | Narrow, V-shaped |
| Dimensions | 2-3 cm in length, 0.5-1 cm in width |
| Boundaries | Medial lip formed by greater tubercle, lateral lip formed by lesser tubercle |
| Surface Features | Smooth, concave floor with foramina |
| Muscles | Subscapularis, supraspinatus, infraspinatus, teres minor |
| Clinical Significance | Entrapment of biceps tendon, fractures |
Question 1:
What is the purpose of the intertubercular groove of the humerus?
Answer:
The intertubercular groove of the humerus serves as a passageway for the long head of the triceps brachii muscle and radial nerve.
Question 2:
Where is the intertubercular groove of the humerus located?
Answer:
The intertubercular groove of the humerus is located on the posterior aspect of the proximal humerus, between the greater and lesser tubercles.
Question 3:
What are the anatomical landmarks associated with the intertubercular groove of the humerus?
Answer:
The intertubercular groove of the humerus is bordered by the greater tubercle laterally and the lesser tubercle medially. The groove runs obliquely from the posterior aspect of the humerus towards the anterior aspect.
Alright folks, that’s all there is to know about the intertubercular groove of the humerus. I know it’s a bit of a mouthful, but hopefully, you’ve found this article helpful. Thanks for sticking with me through all the anatomical jargon! I hope this has helped you appreciate the complexity and beauty of the human body. If you’re interested in learning more about the humerus or any other part of the human anatomy, be sure to check back soon. I’ll be posting new articles regularly, so stay tuned!