Sign-in to Ask A Doctor - 24x7
OR
Sign in with Google
What Causes Numbness In The Right Foot?
Question: My son had sudden numbness in his right foot and the outside of lower right leg. He then developed excruciating pain in the middle of his back. He can barely walk and has no control of his foot as it "gives out" on him. What could these be symptoms of?
Brief Answer:
Disk herniation
Detailed Answer:
I read your question carefully and I understand your concern.
Given the relation of the symptoms in the lower limb with the back pain the most likely cause would be compression of a nerve root in his back. Compression is usually from a bulging of one of the cartilage disks situated between the vertebrae, a disk herniation. At times it may also be due to chronic arthritis changes, but that is unlikely given his young age. Because the nerves exiting the lumbar spine reach the foot symptoms involve pain from the back where the compression happens radiating to the foot, with sensory symptoms like numbness and motor weakness of the areas and muscles controlled by that nerve.
Usually first only rest, pain killers and gradually physical therapy is recommended, more aggressive approach like surgery only if symptoms persist over weeks. So usually MRI can wait as it doesn't change approach.
Reasons for urgent imaging would be symptoms like fever and weight loss which could indicate another cause such as infection as well as symptoms like bladder control issues weakness of both lower limbs which might indicate severe compression of the nerve roots bundle, the cauda equina .
However one cause to speed imaging up would also be if the compression causes marked motor weakness due to the fear for a permanent weakness, so if his foot persists giving out on him, imaging and surgery considerations should be done earlier then other cases (with only pain and numbness).
I remain at your disposal for other questions.
Disk herniation
Detailed Answer:
I read your question carefully and I understand your concern.
Given the relation of the symptoms in the lower limb with the back pain the most likely cause would be compression of a nerve root in his back. Compression is usually from a bulging of one of the cartilage disks situated between the vertebrae, a disk herniation. At times it may also be due to chronic arthritis changes, but that is unlikely given his young age. Because the nerves exiting the lumbar spine reach the foot symptoms involve pain from the back where the compression happens radiating to the foot, with sensory symptoms like numbness and motor weakness of the areas and muscles controlled by that nerve.
Usually first only rest, pain killers and gradually physical therapy is recommended, more aggressive approach like surgery only if symptoms persist over weeks. So usually MRI can wait as it doesn't change approach.
Reasons for urgent imaging would be symptoms like fever and weight loss which could indicate another cause such as infection as well as symptoms like bladder control issues weakness of both lower limbs which might indicate severe compression of the nerve roots bundle, the cauda equina .
However one cause to speed imaging up would also be if the compression causes marked motor weakness due to the fear for a permanent weakness, so if his foot persists giving out on him, imaging and surgery considerations should be done earlier then other cases (with only pain and numbness).
I remain at your disposal for other questions.
Note: For further queries, consult a joint and bone specialist, an Orthopaedic surgeon. Book a Call now.
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
Get personalised answers from verified doctor in minutes across 80+ specialties
