The neuromuscular junction is the site of the signal exchange. The steps of this process in vertebrates occur as follows:(`) The action potential reaches the axon terminal. (2) Voltage-dependent calcium gates open, allowing calcium to enter the axon terminal.he neuromuscular junction is the site of the signal exchange. The steps of this process in vertebrates occur as follows:(`) The action potential reaches the axon terminal. (2) Voltage-dependent calcium gates open, allowing calcium to enter the axon terminal.
Sudden onset pain on the outer side of the foot can be from a fracture of the 5th Metatarsal and injuries to this bone are a common sports injury. Causes of pain on the outside of the foot are listed here: 1  Midtarsal Joint Sprain A mid tarsal joint sprain is an injury to the ligaments holding the mid tarsal joint together causing pain in the outside middle of the foot. 2  Peroneus Brevis Tendon Injury The Peroneus Brevis tendon inserts into the 5th matatarsal bone on the outside of the foot.
Sciatica. Any disorder of the sciatic nerve will cause lower back and leg pain. Sciatica is characterized by leg numbness, tingling feet and toes, pain or weakness on the foot or leg on one side and sometimes even on both sides.Pain in the buttocks and the lower back is also to be expected.There are different causes of sciatic pain.eg Numbness Treatment. Most cases of foot and leg numbness, tingling and pain cannot be resolved if the cause is not treated. Treatments differ for each case, ranging from altering the patientâs activities, to taking in medication for the pain and inflammation, to surgery, or a combination of these.