When people either imagine they have foot drop or actually have it but a cause has not yet been diagnosed, ALS may swoop into their minds like a vulture.
Normally, when a person notices what fits the bill for foot drop, they will not think of ALS unless they are in the midst (or were once in it) of an ALS panic groove.
This is because anyone who googles about muscle twitching will come upon ALS sites, read up on this killer disease and learn about its signature foot drop.
If the anxiety is bad enough, then every stubbed toe, difficulty getting on a shoe, foot slipping off the pedal of a stationary bike – every little nuance in one of their feet will mean the beginnings of foot drop – caused by ALS.
Ironically, there are numerous causes for foot drop other than ALS.
You first need to know about the peroneal nerve: It innervates the muscles that control dorsiflexion: flexing the foot upward (as you do when walking, trimming your toenails or moving from one pedal to the other while driving). In foot drop, dorsiflexion is impaired or not possible.
Harmless Causes of Foot Drop: Don’t Obsess Over ALS – Check out These Benign Culprits
Leg crossing if habitual. This can irritate the peroneal nerve.
Yoga. Pressure from various positions (namely prolonged sitting on the heels) can irritate the peroneal nerve.
Bungee jumping. Pressure from the cord can cause peroneal nerve palsy.
Weight loss: significant. The rapid reduction of the fatty protective cushion around the peroneal nerve can cause palsy.
Chronic exertional compartment syndrome. The acute version can cause permanent muscle damage, but chronic cases are more easily resolved. CECS is caused by exercise and affects muscles and may impair peroneal nerve function.
Sciatica. The sciatic nerve originates in the lower spine and extends down the leg to the foot.
Lumbar disc herniation
More Serious Causes of Foot Drop
Lumbar synovial cyst
Pelvic hydatid cyst
Anterior tibialis tendon rupture. The anterior tibialis is the main muscle in the front of the lower leg, responsible for dorsiflexion.
Spinal stenosis (narrowing of the spinal canal)
Neurofibromatosis. A genetic disorder, usually diagnosed in childhood, that a person may not know they have until they’re a young adult and symptoms are bothersome enough to seek medical evaluation. Benign tumors form on nerve tissue.
Life Threatening Causes of Foot Drop other than ALS and MS
Diabetes. Though one can live a long life if their diabetes is well-managed, improper management can be fatal.
Meningioma. A benign tumor of the meninges, it can encroach upon the brain and for that reason is considered a brain tumor.
Stroke. Some strokes are very small, but having a small stroke means you’re at high risk for a future massive stroke without medical management.
Foot drop from stroke is extremely rare, but when it happens, it’s sudden.
DVT: deep vein thrombosis. A venous blood clot in the pelvis or limb isn’t life-threatening in and of itself, but if a piece of it breaks off and travels to the lungs, it can kill within minutes.
Lymphoma (type of cancer) of the sciatic nerve
Brain tumor metastasis from a distant primary site such as the lungs
Though a few of these more serious causes of foot drop would be devastating to hear, they’d still be more welcome than to hear a diagnosis of ALS.