Time is Brain, Time is Testicle, Time is…Spine?
CASE
A 56 year-old right hand dominant male presented to the emergency department with weakness in his bilateral hands, worse on the left. For the last several months, he had been having daily neck pain and frequent occipital headaches. He had been dropping things more frequently, but noticed over the previous week that he had increasing difficulty getting dressed in the morning. He used to be very active, but began using a walker last year because of frequent falls from what he described as always “feeling off-balance”. He also endorsed intermittent tingling in all fingers of his left hand. He denied recent trauma, fever/chills, bowel or bladder retention or incontinence, or personal history of cancer. His past medical history was significant only for hypertension. He denied tobacco, alcohol or drug use.
On exam, he was a well-developed middle-aged man. There was no midline spinal tenderness and he had full strength in his upper extremities bilaterally. There was slightly decreased (4/5) strength in lower extremity flexor muscle groups bilaterally, but full strength with extension. Sensation was intact throughout his extremities. He also had hyperreflexia in all of his extremities. Positive Hoffman’s sign on the left upper extremity. Rectal tone was normal. Romberg’s test was positive and he ambulated with wide-based, ataxic gait with his walker.
Figure 1: CT c-spine shows multiple degenerative changes of the cervical spine including loss of vertebral body height, osteophytes, straightening of cervical lordosis and ossification of the posterior longitudinal ligament. Image courtesy of sciencephoto.com
Orthopedic surgery spine service was consulted and requested an MRI to evaluate the cord integrity.
Figure 2: T2 weighted sagittal MRI of the cervical spine showing multi-level epidural encroachment due to osteophyte formation. Hyperintensity of the spinal cord with circumferential absence of CSF signal, concerning for cervical myelopathy. Image courtesy of Iain Kalfas, MD and spineuniverse.com
DIAGNOSIS
Cervical myelopathy
DISCUSSION
Definition and Epidemiology
Cervical myelopathy is a syndrome of spinal cord dysfunction caused by compression of the spinal cord. Cervical myelopathy is most commonly caused by degenerative disease of the spine (spondylosis), but other etiologies include mass effect (tumor or abscess), trauma, ossification of the posterior longitudinal ligament (OPLL), and congenital stenosis. It most commonly affects individuals over the age of 50. The incidence and prevalence of cervical myelopathy are poorly quantified, but studies have estimated them to be 41 and 605 per million in North America, respectively, for degenerative cervical myelopathy alone.
Clinical Presentation
There is not a well-defined pattern of symptoms and neurologic deficits in cervical myelopathy. Patients experience a wide constellation of symptoms, which are typically insidious in onset, and often progress in a stepwise manner. Patients may experience neck pain, weakness or loss of dexterity of their upper extremities, paresthesias, and gait instability. Urinary retention appears late in disease progression. The textbook case might describe gait impairment with bilateral loss of hand dexterity and issues with activities such as buttoning a shirt, writing, or holding small objects.
Clinching the Diagnosis
Symptoms often precede objective exam findings, but exam findings will include:
Motor signs:
Pyramidal weakness
Grip and release test (normally a patient can make a fist and release 20 times in 10 seconds. Myelopathic patients may struggle to do this)
Finger escape sign (when patient holds fingers extended and adducted, the small finger spontaneously abducts due to weakness of intrinsic muscle)
Upper motor neuron signs: hyperreflexia, inverted radial reflex, upgoing Babinski, positive Hoffman’s sign, clonus
Sensory signs:
Decreased pain/temperature sensation
Proprioception dysfunction (Positive Romberg’s test)
L’hermitte sign – electric shock sensation down spine on neck flexion or extension
Wide-based ataxic or spastic gait
Choice of an initial imaging modality should be guided by the suspected etiology of the myelopathy. If trauma is suspected, CT without contrast is the most appropriate radiologic test. However, in all other cases MRI is the best choice to evaluate integrity of the cord, and will likely be needed in traumatic cases after a CT is obtained. On MRI or CT, an anterior-to-posterior canal diameter of less than 10mm is highly suggestive of stenosis, but not specific for myelopathy. Cord signal changes on MRI are highly suggestive of disease, although degree of abnormality may not be correlated with disease severity. Hyperintensity on T2-weighted images in the setting of symptoms likely indicates acute cord edema and/or ischemia. Hypoinensity on T1 weighted images, though less sensitive, is more specific for cervical myelopathy and disease severity. Electromyography and nerve conduction studies are likely not helpful. There is no “gold standard” in imaging for diagnosis, and we must look at the whole clinical picture.
Why Early Diagnosis Matters
Time is spine. Like the brain, the spine has limited capacity for regeneration, and damage is often permanent. However, with early diagnosis, patients can have surgery to halt disease progression and preserve quality of life. Without treatment, patients will have progressive neurological decline. Identifying this as early as possible is critical, as patients with milder symptoms prior to surgery, and less than six months of symptoms have better outcomes.
Treatment
The only definitive treatment is surgery. Non-operative management, including physical therapy, anti-inflammatory medications/injections, and lifestyle modifications may help with symptom relief but will not improve outcomes or halt disease progression.
TAKE AWAYS
There is no well-defined pattern of symptoms in cervical myelopathy; patients can present with varying deficits, which often have an insidious onset, likely contributing to a delay in diagnosis.
Always think about this diagnosis in any patient complaining of unsteady gait or nonspecific weakness or clumsiness of the upper extremities, even if they do not yet have any objective weakness on exam.
MRI is the test of choice to evaluate cord compression, but no imaging modality is the “gold standard” in this disease.
The only definitive treatment is surgery.
Author: Meredith Horton, MD
Faculty Reviewer: Adam Alusio, MD
REFERENCES
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