Case History #199

Date of Consultation: 7-17-1985

HISTORY OF PRESENT ILLNESS:

This 75-year-old right-handed white female retired LVN was referred for evaluation of bilateral lower limb signs and symptoms. Approximately 20 years prior to consultation, the patient noted the gradual onset of weakness and stiffness in both lower limbs, although the right side seemed worse than the left. These lower limb symptoms were slowly progressive, such that she had to retire from her job in the hospital by the early 1970s, and, by the time of consultation, she had to use a walker or a cane when walking. She indicated that she was unable to “control her knees”, and they tended to hyperextend when she attempted ambulation. Her toes also dragged on the ground, and this made walking difficult. On occasion, she experienced muscle cramps in her legs at night. She denied any sensory symptoms in the lower limbs, bowel or bladder incontinence or retention, dysphagia, dysarthria, cognitive problems, or emotional lability. She denied any upper limb weakness or stiffness, but she had noticed numbness and tingling of the thumb and first three fingers of both hands intermittently during the prior two years. Pantopaque myelograms of the entire spinal canal were performed in 1965 and 1970 and were unremarkable, except for a mild asymmetry of nerve root sheath filling at L4-5 on the right. CSF analysis on both occasions was entirely normal, including CSF VDRL and multiple sclerosis studies. Her past medical history was remarkable only for mild hypertension, and no family history of neurological problems or similar symptoms was present.     

NEUROLOGICAL EXAMINATION:

Mental Status Exam: Intact.

Cranial Nerves: Cranial nerve examination was entirely normal.

Motor System: There were no areas of focal muscular atrophy, except for mild atrophy of the thenar eminence muscles bilaterally. Fasciculations were not observed. Muscle tone was normal in the upper limbs but was increased in the form of spasticity in both lower limbs. Muscle power was essentially normal (5/5) in the upper limbs, except for mild weakness of the thenar eminence muscles bilaterally. In the lower limbs, moderate weakness (4-/5) was present in the hip and knee flexors, hip abductors, and ankle dorsiflexors. Knee extensors, hip adductors, and ankle plantar flexors were rated 4+/5. No involuntary movements were noted.

Reflexes: Deep tendon reflexes (DTRs) were 3+ and symmetric in the upper limbs, and Hoffmann’s signs were present. In the lower limbs, the DTRs were hyperactive (4/4), with sustained ankle clonus bilaterally. The jaw jerk was slightly brisk. Plantar reflexes were extensor bilaterally.

Sensory System: Intact, except for slight hypalgesia involving the palmar surface of the thumb and first 2 ½ fingers bilaterally.

Cerebellar Function: Intact.

Gait and Stance: Regular gait was possible only with a walker and was remarkable for bilateral spasticity, scissoring, foot drop, and support of the lower limbs with knee hyperextension. Tandem gait could not be performed. The Romberg test was not attempted.

Questions:

1. Can this patient’s signs and symptoms be localized to one single area of the central nervous system? If so, where is the neurologic lesion located, and which side of the central nervous system is involved?

2. What regions, levels, and/or structures of the nervous system are involved with signs or symptoms of lower motor neuron (LMN) disease?

3. What regions, levels, and/or structures of the central nervous system are involved with signs or symptoms of upper motor neuron (UMN) disease?

4. The findings in this case represent a classic neurologic syndrome. What is the name of this syndrome?

5. In general, what type of pathologic process is involved in this case?

6. What diagnostic procedure(s) would you undertake at this point?