pearls of neurologic injury and exam

1. 1.When assessing sciatica, you ALWAYS perform a straight leg raise, so why
wouldn’t you apply the same logic when evaluating upper extremity complaints? Check
out this quick tutorial to review three simple nerve tension tests to help you differentiate
upper extremity neurogenic complaints.
2.Although generalizations can be dicey since not all conditions adhere to their
Merck manual description; radiculopathy in a patient under age 50 is most likely from
disc lesion, while radiculopathy in a patient over 50 is more likely from degenerative
stenosis. (2)
3.Radicular complaints from disc lesions and degeneration most commonly follow a
C6 or C7 nerve distribution. In fact, 90% of disc lesions occur at C5/6 (C6 nerve root) or
C6/7 (C7 nerve root). (3-5) However, symptoms of TOS follow an ulnar nerve
distribution, i.e. C8 or T1, in 90% of cases. (6,7)
4.Having a patient hold their arm overhead, i.e., Shoulder abduction sign, can help
differentiate cervical radiculopathy from TOS. Patients with cervical radiculopathy will
find relief in this position while those with TOS will likely experience exacerbation of
symptoms.
5.The ulnar nerve innervates all intrinsic hand muscles, except the lateral
two Lumbricals, Opponens pollicis, Abductor pollicis, and Flexor pollicis brevis, which
are innervated by C8 and T1 via the median nerve. (8) Clinicians can differentiate ulnar
radiculopathy, i.e., cubital tunnel syndrome, from C8–T1 radiculopathy by examining
these five (LOAF) hand muscles via pinch grip strength.

2. 6.Bilateral carpal tunnel syndrome is unlikely and should suggest central cord
involvement, until disproven by MRI. (1)
7.Pronator syndrome is the second most frequent cause of median nerve
compression (9.2% of all cases). (9). This condition occurs from entrapment of the
median nerve by the pronator teres muscle. Nocturnal exacerbations are common in
carpal tunnel syndrome but notably absent in pronator syndrome. Pronator syndrome is
the likely diagnosis when symptoms are reproduced within 30 seconds of applying deep
sustained compression over the pronator muscle, i.e. Pronator compression test. (10)
8.Radial tunnel syndrome commonly mimics or coexists with lateral epicondylitis. In
fact, up to 10% of patients diagnosed with lateral epicondylitis actually have radial
tunnel syndrome. Nocturnal pain is more common in radial tunnel patients than those
with lateral epicondylitis. Most notably, the peak area of tenderness for radial tunnel
syndrome is four finger breaths distal to the lateral epicondyle, i.e. Radial tunnel
compression test. (11)
9.The Arm Squeeze Testcan be used to differentiate between a shoulder and neck
complaint. In short, compressing the affected arm will exacerbate radicular symptoms
via compression of hypersensitized nerves. Compression of the arm will not exacerbate
pain that originates from shoulder dysfunction, i.e. rotator cuff impingement. In a study
of over 1500 patients with arm pain, the Arm Squeeze test showed very high sensitivity
(97%), specificity (>91%), and inter/ intraobserver reliability. (12)
10.Sensory disturbances (i.e. sciatica) can occur from simple irritation or
inflammation of a nerve; however, motor or reflex loss generally signifies a true
compression or more significant pathologic process – that almost always deserves a
more significant response. In many cases, the patient must perform MULTIPLE
repetitions before a motor weakness is uncovered. i.e. observing a single heel raise
maneuver will not catch as many S1 deficits as watching what happens on the
10th repetition.