**History/Background and/or General Information**

Peripheral nerves can be the cause of pain in a variety of conditions.
Examples may include: post-herniorrhaphy pain
(ilioinguinal/iliohypogastric/genitofemoral), iliac crest harvest syndromes
(cluneal nerve, lateral femoral cutaneous nerve), carpal tunnel syndrome
(median nerve), Morton's neuroma, facial pain and headaches (trigeminal and
occipital nerve).

Peripheral nerve blocks may be used for both diagnostic and therapeutic
purposes. Diagnostically, a peripheral nerve block allows the clinician to
isolate the specific cause of pain in an individual patient. The injection of
local anesthetic, with or without steroid may also provide an extended
therapeutic benefit. If the patient does not achieve sustained relief a
denervation procedure via chemical, cryoneurolysis or radiofrequency may be
effective at providing long term relief.  
  
 **Covered Indications**

Peripheral nerve blocks will be considered medically reasonable and necessary
for conditions such as the following diagnostic and therapeutic purposes:

  1. When the patient's pain appears to be due to a classic mononeuritis but the neuro-diagnostic studies have failed to provide a structural explanation, selective peripheral nerve blockade can usually clarify the situation. 
  2. When peripheral nerve injuries/entrapment or other extremity trauma leads to complex regional pain syndrome. 
  3. When selective peripheral nerve blockade is used diagnostically in those cases in which the clinical picture is unclear. 
  4. When an occipital nerve block is used to confirm the clinical impression of the presence of occipital neuralgia. Chronic headache/occipital neuralgia can result from chronic spasm of the neck muscles as the result of either myofascial syndrome or underlying cervical spinal disease. It may be unilateral or bilateral, constant or intermittent. Nerve injury secondary to a blow to the back of the head or trauma to the nerve from a scalp laceration can also cause this condition. Most commonly it is caused by an entrapment of the occipital nerve in its course from its origin from the C2 nerve root to its entrance into the scalp through the mid portion of the superior nuchal line. Blockage of the occipital nerve can confirm the clinical impression of occipital neuralgia particularly if the clinical picture is not entirely typical. If only temporary relief of symptoms is obtained, neurolysis of the greater occipital nerve may be considered via multiple techniques including radiofrequency and cryoanalgesia. In addition, the lesser and third occipital nerves can be involved in the pathology of headaches, and can be treated in a similar manner.
  5. When the suprascapular nerve block is used to confirm the diagnosis of suspected entrapment of the nerve. Entrapment of the suprascapular nerve as it passes through the suprascapular notch can produce a syndrome of pain within the shoulder with weakness of supraspinatus and infraspinatus muscles. When the history and examination point to the diagnosis, a suprascapular nerve block leading to relief of pain can confirm it. This may be followed by injection of depository steroids that sometime provide lasting relief.
  6. When the trigeminal nerve is blocked centrally at the trigeminal ganglion, along one of the three divisions or at one of the many peripheral terminal branches (i.e., supraorbital nerve).
  7. Nerve blocks as preemptive analgesia
    1.  When a single injection peripheral nerve block provides post-surgical pain control 
      1. during the transition to oral analgesics
      2. in those procedures which cause severe pain normally uncontrolled by oral analgesics
      3. in cases otherwise requiring control with intravenous or parenteral narcotics.
      4. in cases where the patient cannot tolerate treatment with narcotics due to allergy or side effects, etc. 
    2. When a continuous peripheral nerve block provides the same as above, and furthermore may provide extended (i.e., one to five or more days) relief as a result of chronic administration of anesthetic.

Preemptive analgesia starts before surgery, and a presumption of medical
necessity is being made before the fact. Therefore, based on generally
accepted clinical standards and evidence in peer reviewed medical literature
the surgical procedure must be of such nature that the patient would benefit
from the preemptive analgesia.

Medical management using medications, behavioral therapy, and physical therapy
should be used (when appropriate) in conjunction with peripheral nerve block.

Injection of depository steroids, may offer only temporary relief. In some
cases, neurolysis may be appropriate to provide lasting relief.  
  
 **Limitations**

  1. The signs and symptoms that justify peripheral nerve blocks should be resolved after one to three injections at a specific site. More than three injections per anatomic site (e.g., specific nerve, plexus or branch as defined by the CPT code description) in a six month period will be denied.
  2. More than two anatomic sites (e.g., specific nerve, plexus or branch as defined by the CPT code description) injected at any one session will be denied. If the patient does not achieve progressively sustained relief after receiving two to three repeat peripheral nerve block injections on the same anatomical site, then alternative therapeutic options should be explored.
  3. There is insufficient evidence to support the use of peripheral nerve blocks in the treatment of diabetic peripheral neuropathy.
  4. The use of nerve blocks with or without the use of electrostimulation, and the use of electrostimulation alone for the treatment of multiple neuropathies or peripheral neuropathies caused by underlying systemic diseases is not considered medically reasonable and necessary. Medical management using systemic medications is clinically indicated for the treatment of these conditions.
  5. At present, the literature and scientific evidence supporting the use of peripheral nerve blocks with or without the use of electrostimulation, and the use of electrostimulation alone for neuropathies or peripheral neuropathies caused by underlying systemic diseases is insufficient to warrant coverage. These procedures are considered investigational and are not eligible for coverage for the treatment of neuropathies or peripheral neuropathies caused by underlying systemic diseases.
  6. More than three injections per anatomic site (specific nerve, plexus or branch as defined by the CPT code description) in a six month period will be denied.
  7. More than two anatomic sites (specific nerve, plexus or branch as defined by the CPT code description) injected at any one session will be denied.

As published in the CMS IOM Publication 100-08, _Medicare Program Integrity
Manual_ , Chapter 13, Section 13.5.4, an item or service may be covered by a
contractor LCD if it is reasonable and necessary under the Social Security Act
Section 1862 (a)(1)(A). Contractors shall determine and describe the
circumstances under which the item or service is considered reasonable and
necessary.