Subacute Toe Numbness in a 70 year old

By

Kenneth A. Vatz, M.D.

70 year old female with numbness in the toes of both feet for the past few months without significant back pain or sciatica, and without a history of diabetes or hypothyroidism or ethanol abuse.

 The directed clinical neurologic examination of the lower extremities was essentially normal, including vibratory and position sense.

 Non-enhanced MRI scan of the lumbar spine was essentially unremarkable, and nothing to explain the diffuse denervation in the paraspinal musculature.

Non-enhanced MRI scan of the thoracic spine showed diffuse degenerative changes from about T6-T12 but no cord compression.

Questions:

1) Do the EMG/NCS findings warrant a CSF study to rule out an infiltrative process such as lymphoma?

 2) Does the study suggest a peripheral neuropathic process instead of or in addition to radiculopathies? (Note the preserved sural sensory potential in the foot.)

Motor Nerve Study

1)Right Peroneal Nerve

Rec Site: EDB             Lat (ms)           Dur (ms)                   Amp (mV)                 Dist (mm)                     C.V. (m/s)

STIM SITE

Ankle                             4.6                   6.5                              3.9                                0                                                                                             
Fib.Head                       12.0                  6.9                              2.8                             300                                40.2                        
Pop.Fos.                       13.6                  6.4                              2.4                               70                                45.7                        
 

2)Right Tibial Nerve

Rec Site: ADQ             Lat (ms)          Dur (ms)                   Amp (mV)                 Dist (mm)                     C.V. (m/s)
STIM SITE
Ankle                              4.7                  2.9                             0.900                             0                                                                                             
Pop.Fos.                       13.3                  4.6                             0.467                         410                              47.7                        

 

Sensory Nerve Study

1) Right Peroneal Nerve

Rec Site: dors.ft            Lat (ms)         Pk Lat (ms)               Amp (uV)            Dist (mm)
STIM SITE
Lower leg                         2.8                  3.8                             3.1                      140                         

 

2)Right Sural Nerve

Stim Site: calf                Lat (ms)         Pk Lat (ms)               Amp (uV)           Dist (mm)
REC SITE
Ankle                                3.3                 3.8                             4.5                      140                         

 

3)Right Sural foot Nerve

Stim Site: Ankle             Lat (ms)         Pk Lat (ms)              Amp (uV)             Dist (mm)
REC SITE

dors.ft                              3.9                  4.3                             4.6                        0                              

 

EMG Study

Name                                      Ins Act     Fibs        PSW       Fascics      Polyph      MU Amp       MU Dur      Recruit        Nascents              
R. Tibialis An                            norm      none        none         none           inc            norm               inc            decr              none
R. Peroneus Ln                          norm     none        none          none          inc             norm              inc             norm            none
R. Gastroc.Med        Normal                                                                                                                                                  
R. Rectus Fem.         Normal                                                                                                                                                  
R. Gluteus Med         Normal                                                                                                                                                  
L. Tibialis An                             norm     none        none          none          inc             norm              inc             norm            none
L. Peroneus Ln                           norm     none        occ           none          none          norm              norm          decr             none
L. Gastroc.Med         Normal                                                                                                                                                  
L. Gluteus Med                           inc        none        none          none          none          norm              norm          norm           none
R. LumbarParas                          norm     none        3+             none                                                                               
L. LumbarParas                           norm     none        2+             none                                                                                
R. UpperThorPa                          norm     none        2+             none

 

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(c) 2001 Medical College of Georgia

Revised 09/24/2001