Medication Summary
The goals of pharmacotherapy are to reduce morbidity and prevent complications.
Antidepressants, TCAs
Class Summary
The analgesic properties of certain agents in this class may improve symptoms if painful paresthesias develop.
Amitriptyline
Amitriptyline is an analgesic for certain chronic and neuropathic pain. It blocks the reuptake of norepinephrine and serotonin, which increases their concentration in the central nervous system (CNS). Amitriptyline decreases pain by inhibiting spinal neurons involved in pain perception. This agent is highly anticholinergic. It is often discontinued because of somnolence and dry mouth. Cardiac arrhythmia, especially in overdose, has been described; monitoring the QTc interval after reaching the target level is advised. Up to 1 month may be needed to obtain clinical effects.
Nortriptyline (Pamelor)
Nortriptyline increases the concentration of serotonin and norepinephrine in the central nervous system by inhibiting their reuptake by the presynaptic neuronal membrane. It has demonstrated effectiveness in the treatment of chronic pain.
Desipramine (Norpramin)
This is the original tricyclic antidepressant used for depression. These agents have been suggested to act by inhibiting reuptake of noradrenaline at synapses in central descending pain modulating pathways located in the brainstem and spinal cord.
Antidepressants, SNRIs
Class Summary
Pharmacologic agents with reuptake inhibition of serotonin and norepinephrine such as duloxetine (Cymbalta) may be helpful in a variety of mood and anxiety disorders. Duloxetine is also cleared for use for chronic musculoskeletal pain, anxiety, and depression. It can be used for neuropathy and has also been used for fibromyalgia.
Duloxetine (Cymbalta, Irenka)
Duloxetine is a potent inhibitor of neuronal serotonin and norepinephrine uptake, and antidepressant action is thought to be due to serotonergic and noradrenergic potentiation in the central nervous system.
Anticonvulsants, Other
Class Summary
Some agents in this category have shown benefit by improving symptoms if painful paresthesias develop.
Pregabalin (Lyrica)
Pregabalin is a structural derivative of gamma-aminobutyric acid (GABA). Its mechanism of action is unknown. The drug binds with high affinity to the alpha2-delta site (a calcium channel subunit). In vitro, it reduces the calcium-dependent release of several neurotransmitters, possibly by modulating calcium channel function. Pregabalin has been approved by the US Food and Drug Administration (FDA) for neuropathic pain associated with diabetic peripheral neuropathy or postherpetic neuralgia and as adjunctive therapy in partial-onset seizures.
Gabapentin (Neurontin)
Gabapentin, a membrane stabilizer, is a structural analogue of the inhibitory neurotransmitter GABA, although, paradoxically, it is thought not to exert an effect on GABA receptors. It appears to exert its action via the alpha2delta1 and alpha2delta2 auxiliary subunits of voltage-gaited calcium channels. Gabapentin is used to manage pain and provide sedation in neuropathic pain.
Hematopoietic Growth Factors
Class Summary
Agents in this class may be used for the treatment of anemia but also has neuroprotective and possibly neurotrophic properties.
Epoetin alfa (Epogen, Procrit)
This is a recombinant erythropoietin that has been shown to accelerate functional recovery after peripheral nerve injury. The proposed mechanism of action is antiapoptotic and anti-inflammatory, promoting cell survival. Erythropoietin is given in 3 doses of 5000 U/kg over 1 week after nerve injury.
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Diagram of ground reaction vector during heel strike.
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Common and superficial peroneal nerves, branches, and cutaneous innervation.
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Deep peroneal nerve, branches, and cutaneous innervation.
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Incisions for Bridle procedure.
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Posterior leg with retrieved posterior tibial tendon above ankle. Window in interosseous membrane is labeled with X.
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Posterior tibial tendon (C) is pulled through slit in anterior tibial tendon (A) and inserted into second cuneiform. Posterior tibial tendon is anastomosed to anterior tibial tendon and distal stump of peroneus longus (B) that has been rerouted anterior to lateral malleolus.
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Gait of patient with foot drop.
