Review Question - QID 214009

This patient has severe right sided foraminal stenosis with disc protrusion on MRI imagin at the C6-7 level which would cause a C7 radiculpathy. Examination of the hand would show weakness of index and little finger extension > than middle and ring finger.

With a reported incidence of 5.5 per 100,000, cervical disc herniation commonly leads to cervical radiculopathy, defined as radicular pain and sensory deficit with possible weakness following the path of the affected nerve’s dermatomal distribution. In the cervical spine, a disc herniation will affect the nerve root below the herniation (ex. C6/7 herniation will affect the C7 nerve root). Clinical findings suggestive of a C7 cervical radiculopathy include triceps and wrist flexion weakness, diminished triceps reflex, and paresthesia in the middle finger. A C7 cervical radiculopathy is the most commonly affected nerve root. MRI is the imaging modality of choice.

Thoomes et al compared the results of diagnostic tests performed during a physical examination in diagnosing cervical radiculopathy with a reference standard of imaging or surgical findings. They report that only Spurling's test was evaluated in more than one study, with a specificity and sensitivity ranging from 0.89 to 1.00 and 0.38 to 0.97, respectively. No studies were found that assessed the diagnostic accuracy of widely used neurological tests such as key muscle strength, tendon reflexes, and sensory impairments. They concluded that there is limited evidence for accuracy of physical examination tests for the diagnosis of cervical radiculopathy.

Wong et al reviewed the natural history, clinical course, and prognostic factors of symptomatic cervical disc herniations with radiculopathy. They found that most patients with symptomatic cervical disc herniations with radiculopathy initially present with intense pain and moderate levels of disability. They report that substantial improvements tend to occur within the first 4 to 6 months with complete resolution ranging between 24 to 36 months in most patients. They conclude that most patients with symptomatic cervical spine disc herniation with radiculopathy recover.

Figure A are the sagittal and axial MRI images demonstrating right sided foraminal stenosis at C6/7. Illustration A depicts the cervical dermatomes.

Incorrect Answers:
Answer 1: Bicep weakness would suggest a C5 radiculopathy
Answer 2: Brachioradialis weakness would suggest a C6 radiculopathy
Answer 3: Intrinsic hand muscle weakness would suggest a T1 radiculopathy
Answer 4: Wrist extension weakness would suggest a C6 radiculopathy