College of Massage Therapists of British Columbia (CMTBC) Practice Exam

Ape Hand Deformity is a result of which nerve palsy?

1. Ulnar Nerve

2. Median Nerve

3. Radial Nerve

4. Musculocutaneous Nerve

The correct answer is: Median Nerve

Ape Hand Deformity is primarily associated with median nerve palsy. This condition arises from the functional impairment of the muscles innervated by the median nerve, which includes the thenar muscles that control thumb opposition and flexion. As a result, the individual may exhibit a hand posture where the thumb is positioned in a plane parallel to the other fingers, leading to the characteristic apes-like appearance. The median nerve's role extends to providing the ability to grasp objects by enabling fine motor control of the thumb. When the nerve is damaged or compromised, the thenar muscles atrophy over time, significantly affecting the hand's functional capabilities. The absence of thumb opposition drastically limits the ability to perform tasks requiring a grip, resulting in the deformity observed. Knowledge of the specific upper limb nerve functions and the associated deformities upon their injury is crucial for diagnosing and formulating effective rehabilitation plans, particularly within the context of massage therapy and supportive care.