What can result from unilateral muscle relaxation in a patient receiving regional anesthesia?

• A. Severe dehydration
• B. Scoliosis
• C. Increased heart rate
• D. Lowered blood pressure

Answer: (B)

Unilateral muscle relaxation as a result of regional anesthesia can indeed lead to scoliosis. This occurs because the relaxation affects only one side of the muscle group, which can create an imbalance. For instance, if one side of the back muscles becomes relaxed while the other side remains tense, it can lead to a lateral curvature of the spine, known as scoliosis. This curvature occurs due to the unequal forces acting on the vertebrae and can influence the alignment of the spine temporarily during the period of muscle relaxation.

The other options do not have a direct relationship with unilateral muscle relaxation caused by regional anesthesia. Severe dehydration is unrelated to muscle relaxation; increased heart rate may occur from other physiological responses but is not directly caused by the relaxation of muscles on one side; and lowered blood pressure may occur in general anesthesia where vasodilation is more prominent but is not a typical consequence of unilateral muscle relaxation in regional anesthesia. Hence, the connection between unilateral muscle relaxation and scoliosis stands out as the most plausible outcome in this context.