The Lateral Plantar Nerve

more nerves

The lateral plantar nerve is branch of the posterior tibial nerve, which originates from the sciatic nerve. Around the medial side of the ankle, close to the tarsal tunnel, the posterior tibial nerve divides into the medial and lateral plantar nerves. anatomy

Thickening of the flexor retinaculum will cause compression of the posterior tibial nerve, which is called tarsal tunnel syndrome. When drawing a line between the medial malleolus and the calcaneus, the posterior tibial nerve divides into branches within 2 cm from this axis. The lateral plantar nerve is interesting because its branches give innervation to most of the intrinsic muscles in the foot—similar to the ulnar nerve in the hand. The lateral plantar nerve is also important due to its first branch being the Baxter’s nerve. baxter

This nerve is always mentioned in nerve entrapment in running athletes and is associated with chronic heel related pain. The pain associated with the Baxter’s nerve is very similar to the pain associated with plantar fasciitis; the pain is in the same location, the mechanical symptoms are the same, and there is nerve pain unassociated with weight-bearing.

The first branch of the lateral plantar nerve gets compressed between the fascia of the abductor hallucis muscle and the medial side of the quadratus plantae muscle. This condition may require surgical release of the abductor hallucis fascia if conservative treatments and injections do not produce any effect.

In summary, the lateral plantar nerve:

  • Is similar to the ulnar nerve in the hand
  • Supplies most of the intrinsic muscles of the foot
  • Supplies the Baxter’s nerve branch
  • Can be injured during surgery (rod placement from the heel).

sustainAnother point of interest when it comes to the lateral plantar nerve is the hardware placement. Hardware placement prominent to the sustentaculum tali can injure the flexor hallucis longus tendon and the lateral plantar nerve.

Compartment Syndrome in Children

armswell

Compartment Syndrome in children can go unrecognized due to how difficult it can be to examine a child. Children have a poor perception of numbness and paresthesia and they tend to cry from injuries or fear. The actual amount of pain that a child feels cannot be estimated. It can also be challenging to remove splints or dressings in order to examine a child. In adults, well established compartment syndrome is historically defined by the 5 P’s:fivep

  1. Pain/Swelling
  2. Pulselessness
  3. Paresthesia
  4. Pallor
  5. Paralysis

These 5 P’s occur in established compartment syndrome and when these findings are present it is usually too late. These findings are considered late presentation. If the pressure is not released within 6-8 hours from its onset, there is irreversible damage to the muscles. Note for the diagnosis of impending Compartment Syndrome: it is better to diagnose compartment syndrome when it is impending rather than when it is established. The majority of clinicians will depend on a high index of suspicion supplemented by the clinical diagnosis and pressure measurements. Usually the clinician’s findings of impending Compartment Syndrome are—pain greater than after surgery or injury, tense swelling, and pain with passive stretch. pressure measureIf compartment syndrome is suspected, measure the compartment pressure if you can. If the compartment pressure is greater than 30mHg (absolute measurement), or within 30mmHg of the diastolic pressure, then an immediate fasciotomy should be performed. These clinical findings are different in children and physicians are usually not familiar with how compartment syndrome presents itself in children.

Clinical findings in children include:

  • Increased pain with an increase in pain medication
  • Increased agitation
  • Increased anxiety of the child, parents, and nurses

For example, if a doctor goes on the floor and finds the nurses are with the parents in the room of the child and the child is in pain and everyone else is quiet, then there is a problem. The doctor should begin with removing the dressing and checking the extremity. Bivalving the cast will decrease the pressure significantly. When in doubt, measure the pressure. Objective findings, such as measuring the pressure, may be necessary to exclude the presence of compartment syndrome in children. The doctor may rely on his clinical judgment alone to diagnose compartment syndrome and perform a fasciotomy. However, the doctor should not rely on their clinical judgment alone to exclude compartment syndrome, especially if the patient has other findings of compartment syndrome.

dressing

Areas of concern for the development of compartment syndrome in children are: high energy fractures, multiple fractures in the same extremity (such as: floating elbow), multiple closed reductions, and/or the use of a fibroblast cast—which can be two times tighter than plaster. It is important to fix the fracture and provide post-operative monitoring with a possible delay in feeding the patient. A delay in diagnosis may lead to a poor outcome.

The use of an ACell can help with skin graft regeneration and may be used in an outpatient basis to cover the defect. The use of a VAC is always helpful.

Stinger/Burner Nerve Injury

A “stinger” or “burner” is a common transient injury that occurs in contact sports such as football. The injury occurs from stretching the upper trunk of the brachial plexus or compression of the C5-C6 nerve root.

contactStretching of the brachial plexus is the mechanism of injury typically seen in high school aged athletes suffering from this condition. This injury occurs from a direct blow, causing the shoulder to be depressed and forcing the neck into lateral flexion, causing the neck to bend toward the opposite side.

stretchingCompression of the nerve root is the basis of injury most often associated with older athletes. It is not a cervical cord injury and it is not a transient quadriplegia.

compressionThe patient will complain of burning pain, numbness, and weakness with painful symptoms starting above the shoulder, going down to the arm. Symptoms will begin immediately after the trauma occurs and can last from several minutes up to several weeks after the accident, but they will usually resolve themselves. A stinger or burner is a transient, intensely painful nerve injury that may result in time loss from competition.

burner pain

When the injury occurs, the athlete should stop participating in sports until full recovery of strength, sensation, and pain-free range of motion is reestablished to the cervical spine. Treatment consists of alternating between ice and heat, anti-inflammatory medications, and rehabilitation exercises. An MRI may be necessary to rule out a herniated disc. Surgery is usually not necessary for a Stinger/Burner injury.