Lateral cricoarytenoid

Lateral Cricoarytenoid

The lateral cricoarytenoid (LCA) is a muscle located in the larynx, specifically between the cricoid cartilage and the arytenoid cartilage. It plays a crucial role in vocalization and phonation. The LCA is one of the intrinsic muscles of the larynx, responsible for controlling the tension and position of the vocal folds.

Anatomy

The lateral cricoarytenoid muscle originates from the lateral surface of the cricoid cartilage and inserts into the muscular process of the arytenoid cartilage. It is a relatively small muscle, but its actions are vital for vocalization.

Function

The primary function of the lateral cricoarytenoid muscle is to adduct the vocal folds. When the LCA contracts, it brings the arytenoid cartilages closer to the midline, causing the vocal folds to come together. This adduction is essential for producing sound during speech and singing.

Additionally, the LCA also plays a role in controlling the tension of the vocal folds. By adjusting the degree of contraction, the muscle can modulate the pitch and volume of the voice. This fine-tuning ability allows for a wide range of vocal expressions.

Clinical Significance

The lateral cricoarytenoid muscle is crucial for normal vocal function. However, certain conditions can affect its function, leading to voice disorders. For example, if the LCA becomes overly tight or spasms, it can result in a condition called muscle tension dysphonia, characterized by strained or hoarse voice quality.

In some cases, surgical interventions may be necessary to address issues with the lateral cricoarytenoid muscle. Procedures such as vocal fold injection or medialization thyroplasty can help restore proper vocal fold adduction and improve voice quality.

See Also

• Larynx
• Vocal folds
• Muscle tension dysphonia