The video shown in Figure V shows a Lhermitte maneuver which is a provocative maneuver used in the diagnosis of cervical myelopathy. When it is positive the patient will complain of electric shock-like sensations that radiate down the spine and into the extremities.
The Lhermitte sign was originally describe in 1917 to describe the “pins and needles” sensations that passed through the extremities when the neck is flexed. The test is highly specific, but not sensitive, for cervical spinal cord compression or myelopathy. It may be positive in multiple conditions, including multiple sclerosis.
Uchihara et al. studied the relationship between pain with compression of the brachial plexus (BP) and cervical spine pathology. They found pain with compression of the brachial plexus (BP) was quite sensitive and reasonably specific to detect compressive neuropathies of the cervical spine.
Rhee et al. looked at the sensitivity and specificity of different physical exam findings for cervical myelopathy. They found sustained clonus was poorly sensitive (13%) but highly specific (100%) for cervical myelopathy. Given that 20% of myelopathic patients may not have typical exam findings (ie. clonus, babinski, hyperreflxia), they recommend that appropriate patient management be guided by individual history, physical exam and imaging findings.
Figure V demonstrates the Lhermitte provocative maneuver
Answer 2: Involuntary thumb IP joint contraction is associated with a Hoffman’s pathologic reflex
Answer 3: Spontaneously abduction of the 5th digit (finger escape sign) is associated with weak intrinsic muscles in the setting of cervical myelopathy
Answer 4: Spontaneous extension of the great toe may be associated with a pathologic upper motor neuron reflex (i.e. Babinski sign)
Answer 5: Unilateral arm pain and paresthesias in a dermatomal distribution is consistent with cervical radiculopathy and may be elicited with the Spurling test.
Rhee JM, Heflin JA, Hamasaki T, Freedman B. Prevalence of physical signs in cervical myelopathy: a prospective, controlled study. Spine (Phila Pa 1976). 2009 Apr 20;34(9):890-5. doi: 10.1097/BRS.0b013e31819c944b. PubMed PMID: 19352222.
PMID:19352222 (Link to Abstract)
Uchihara T, Furukawa T, Tsukagoshi H. Compression of brachial plexus as a diagnostic test of cervical cord lesion. Spine (Phila PA 1976). 1994 Oct 1;19(19):2170-3
PMID:7809749 (Link to Abstract)