Watch the video version of this Q&A episode on YouTube - https://youtu.be/8knJDlwD0lU 

A patient reports numbness and tingling in the palmar aspect of the thumb, index, and middle fingers. Examination findings reveal pain with resisted pronation and a negative Tinel’s sign at the wrist. Which of the following conditions should the therapist MOST likely suspect?
 
1. Carpal tunnel syndrome
2. Pronator syndrome
3. Anterior interosseous syndrome
4. Cubital tunnel syndrome

Transcript

Welcome back to the Scorebuilders’ Question and Answer Podcast! This podcast provides members of the Scorebuilders’ team with the opportunity to explore challenging multiple-choice examination questions with students actively preparing for the licensing examination. My name is Scott Giles and I will be your host for today’s journey.

Ready? Let’s go!

A patient reports numbness and tingling in the palmar aspect of the thumb, index, and middle fingers. Examination findings reveal pain with resisted pronation and a negative Tinel’s sign at the wrist. Which of the following conditions should the therapist MOST likely suspect?
 
1. Carpal tunnel syndrome
2. Pronator syndrome
3. Anterior interosseous syndrome
4. Cubital tunnel syndrome

The question offers three specific findings that can be used to determine the most likely clinical condition. 

1. numbness and tingling in the palmar aspect of the thumb, index, and middle fingers

A student should recognize that this pattern of sensory disturbance is consistent with the median nerve distribution.

Median Nerve Distribution
2. pain with resisted pronation

The pronator teres muscle is innervated by the median nerve. In addition, the median nerve can become entrapped between the two heads of the pronator teres muscle, often producing pain. 

3. negative Tinel’s sign at the wrist

Tinel’s Sign at the Wrist
A negative test when assessing Tinel’s sign at the wrist would be indicated by the absence of a tingling sensation extending into the palm of the hand. 

The image depicts a positive Tinel’s sign at the wrist.

Now let’s explore each option using the discussed clinical findings.

Option 1 - Carpal tunnel syndrome 
Carpal tunnel syndrome occurs when the median nerve is injured by compression within the carpal tunnel at the wrist. Although the patient in this scenario is reporting paresthesias in the distribution of the median nerve, Tinel’s sign at the wrist was negative. 

Additionally, pain with resisted pronation would not be anticipated with carpal tunnel syndrome. Provocative testing findings for carpal tunnel syndrome typically include a positive Tinel’s sign at the wrist and a positive Phalen’s test.

Option 2 - Pronator syndrome 
Pronator syndrome is an entrapment of the median nerve at the elbow. It’s often associated with activities that require repetitive pronation while grasping an object. Other potential risk factors include underlying conditions such as hypothyroidism and diabetes. 

The paresthesias in the distribution of the median nerve would be expected with both pronator syndrome and carpal tunnel syndrome. However, the negative Tinel’s sign at the wrist and pain with resisted pronation are more typical of pronator syndrome. 

Option 3 - Anterior interosseous syndrome 
Anterior interosseous syndrome is a neuropathy resulting in an isolated palsy of the muscles innervated by this motor branch of the median nerve. The three muscles innervated by the anterior interosseous nerve are in the deep layer of the anterior forearm and include flexor pollicis longus, index and long fingers of the flexor digitorum profundus, and pronator quadratus. 

The classic sign of anterior interosseous syndrome is an inability to perform the “OK” sign by approximating the tip of the index finger to the tip of the thumb. 

Option 4 - Cubital tunnel syndrome 
Cubital tunnel syndrome is an entrapment of the ulnar nerve at the elbow where the nerve passes between the medial epicondyle of the humerus and the olecranon process of the ulna. 

Typical findings would include pain or paresthesias in the distribution of the ulnar nerve (i.e., ring and little fingers) and a positive Tinel’s sign at the elbow.

The correct answer is Option 2

Let’s explore the all student data:
19% of students selected Option 1, Carpal tunnel syndrome
60% of students selected Option 2, Pronator syndrome, the correct response
14% of students selected Option 3, Anterior interosseous syndrome
7% of students selected Option 4, Cubital tunnel syndrome

System Classification
This question is a Neuromuscular and Nervous Systems question which represents approximately 24% of all exam items.

Content Outline Classification
This question is a Foundations for Evaluation, Differential Diagnosis, and Prognosis question which represents approximately 33% of all exam items.

Level Classification
This question is a Level 2 question since the question requires students to integrate numerous pieces of information or to apply knowledge in a given clinical scenario. Remediation of Level 2 questions occurs by increasing flexibility with academic content and by carefully analyzing decision making processes when answering applied examination questions.

Thanks for joining us on the Scorebuilders Q and A podcast! See you next week!