Clinical history: A 26 year-old female presents with lateral foot pain and no prior trauma. Axial T2-weighted (1a) and coronal STIR (1b) images are provided. What are the findings? What is your diagnosis?
Baxter’s nerve (first branch of the lateral plantar nerve) impingement.
Heel pain is a common presenting complaint to the foot and ankle specialist, with a wide differential diagnosis including plantar fasciitis, fat pad atrophy, calcaneal stress fracture or apophysitis, inflammatory arthropathy, neoplasia, and infection1. One of the more elusive diagnostic considerations in heel pain is entrapment of first branch of the lateral plantar nerve (Baxter’s nerve impingement)2,3. Baxter’s nerve is a mixed sensory and motor nerve, providing motor innervation to the abductor digiti minimi (ADM) muscle2,4,5. Baxter’s nerve impingement can produce symptoms indistinguishable from plantar fasciitis6,7,8,9. While this diagnosis has been said to account for up to 20% of heel pain, it is often overlooked relative to other causes of heel pain8,10,11. Weakness of the ADM may be present but is difficult to detect clinically9. Electrodiagnostic studies are invasive and the results in heel pain can be inconclusive9,13,14. MR can be used to detect denervation-related muscle changes in the ADM, confirming the diagnosis of Baxter’s nerve impingement3,6,8,9,12.
Within the ankle tarsal tunnel, the posterior tibial nerve (PTN) bifurcates into medial (MPN) and lateral (LPN) plantar nerves. These nerves exit the tarsal tunnel and continue along the plantar aspect of the foot.
The MPN travels anterior to the LPN, carrying sensory information from the medial two thirds of the plantar foot, and motor innervation to the flexor digitorum brevis, abductor hallucis, flexor hallucis brevis, and first lumbrical9.
The LPN carries sensory information from the lateral plantar aspect of the foot, 5th toe, and lateral half of the 4th toe. Motor innervation involves all the remaining foot muscles, not innervated by the MPN9.
The first branch of the LPN, Baxter’s nerve (also known as the inferior calcaneal nerve), originates from the LPN at various levels beneath the deep fascia of the abductor hallucis muscle. The nerve courses vertically between the abductor hallucis and quadratus plantae muscles, then makes a sharp 90 degree horizontal turn, coursing laterally beneath the calcaneus to innervate the ADM muscle3,5,9,15. Motor innervation supplies the ADM, occasionally to the flexor digitorum brevis and lateral half of the quadratus plantae. Sensory information is carried from the calcaneal periosteum, long plantar ligament, and adjacent vessels3,4,6. While Baxter’s nerve is usually the first branch of the LPN, variation does exist and the nerve can originate directly from the PTN5,14,16.
Two sites of entrapment have been described with Baxter’s nerve impingement. The first site is located as the nerve passes between the deep fascia of the abductor hallucis muscle and the medial plantar margin of the quadratus plantae muscle. The second site is more distally as the nerve passes along the anterior aspect of the medial calcaneal tuberosity2,3,14. A calcaneal plantar enthesophyte3,8 and/or soft tissue changes of plantar fasciitis9 may also contribute to entrapment at this second location.
Similar to entrapment neuropathies elsewhere, resultant effects from nerve compression depend on the severity and chronicity of entrapment. Early diagnosis of a nerve compression syndrome may result in reversible damage, whereas late diagnosis nerve compression damage is not typically reversible17. With motor nerve injuries, skeletal muscle will become edematous in the acute to subacute phases. Left untreated, denervated muscle will eventually undergo volumetric atrophy, ultimately with irreversible fatty infiltration. If dual or redundant innervation exists, these changes may not occur18,19.
Reported risk factors for Baxter’s nerve impingement include advancing age, the presence of a calcaneal spur, plantar fasciitis, underlying mass, vascular enlargement, muscular enlargement (such as in athletes), obesity, and foot hyperpronation3,8,9,20.
MRI has been shown to be extremely valuable in demonstrating muscular changes associated with denervation. MRI is more sensitive to tissue changes within muscle compared to ultrasound or computed tomography and has advantages compared to electrodiagnostic studies due to its non-invasive nature, superior anatomic detail, ability to demonstrate pathology in muscles with dual innervation18, and ability to exclude alternative diagnoses (fracture, neoplasia, fasciitis). Normal muscle demonstrates intermediate signal on T1 and fluid sensitive sequences.
Acute and subacutely muscle denervation is best evaluated with fluid sensitive sequences, such as T2-weighted imaging with fat suppression (T2FS) or short tau inversion recovery (STIR) images, exhibiting increased signal within the muscle belly compared to normal muscle, related to neurogenic muscular edema18,19. Gadolinium enhancement within muscle will also occur in the acute to subacute phases of denervation18. In the setting of Baxter’s nerve impingement, muscular edema will occur selectively within the ADM, and potentially within the flexor digitorum brevis and quadratus plantae, depending on the innervation anatomy of the patient.
Chronically denervated muscle will eventually undergo volumetric atrophy, and subsequent irreversible fatty infiltration. These findings are best depicted on non-fat-suppressed T1-weighted images18,19. Typically, the atrophy and fatty infiltration occurs homogeneously within the muscle belly. If dual or redundant innervation exists, these changes may not occur or may occur heterogeneously18. In the case of Baxter’s nerve impingement, the ADM is typically involved homogeneously, unless dual innervation exists.
Initial treatment strategy of Baxter’s nerve entrapment is conservative, typically involving a combination of rest, non-steroidal anti-inflammatory medicines, corticosteroid injections, and orthotics1,21,22. If recalcitrant pain exists despite conservative treatment, operative intervention has proven successful1,21,23,24. Neurolysis of Baxter’s nerve is performed with deep fascia release of the abductor hallucis muscle. An impinging heel spur or tight plantar fascia is also partially removed or released, if it is associated with the entrapment2. Endoscopic approaches to the surgery11 and radiofrequency ablation techniques22 have also been described. The first patient above (Figures 1a,1b), underwent decompression of the tarsal tunnel in conjunction with Baxter’s nerve release, completely resolving her lateral foot pain.
Baxter’s nerve impingement is a difficult clinical diagnosis and often overlooked in the presentation of heel pain. MRI can be used to evaluate for denervation effects of Baxter’s nerve impingement by identifying abnormalities of the ADM muscle belly. In addition, potential causes of impingement (e.g. calcaneal spur, soft tissue mass, enlarged vessels) and associated pathology (e.g. plantar fasciitis, tendon pathology) may be seen, and alternative differential diagnoses (e.g. stress fracture) can be excluded.
1 Thomas JL, Christensen JC, Kravitz SR, Mendicino RW, Schuberth JM, Vanore JV, Weil LS Sr, Zlotoff HJ, Bouche R, Baker J, American College of Foot and Ankle Surgeons heel pain committee. The diagnosis and treatment of heel pain: a clinical practice guideline-revision 2010. J Foot Ankle Surg 2010; 49(3 Suppl):S1-19.
2 Baxter DE, Thigpen CM. Heel pain: operative results. Foot Ankle 1989; 5:16-25.
3 Recht MP, Groof P, Ilaslan H, Recht HS, Sferra J, Donley BG. Selective Atrophy of the Abductor Digiti Quinti: An MRI Study. AJR 2007; 189:123-127.
4 Rondhuis JJ, Huson A. The first branch of the lateral plantar nerve and heel pain. Acta Morphol Neerl Scand 1986; 24:269-279.
5 Del Sol M, Olave E, Gsabrielli C, Mandiola E, Prates JC. Innervation of the abductor digiti minimi muscle of the human foot: anatomical basis of the entrapment of the abductor digiti minimi nerve. Surg Radiol Anat 2002; 24:18-22.
6 Delfaut EM, Demondion X, Bieganski A, Thiron MC, Mestdagh H, Cotten A. Imaging of foot and ankle nerve entrapment syndromes: from well-demonstrated to unfamiliar sites. Radiographics. 2003; 23:613-623.
7 Oztuna V, Ozge A, Eskandari MM, Colak M, Golpinar A, Kuyurtar F. Nerve entrapment in painful heel syndrome. Foot Ankle Int 2002; 23: 208-211.
8 Chundru U, Liebeskind A, Seidelmann F, Fogel J, Franklin P, Beltran J. Plantar fasciitis and calcaneal spur formation are associated with abductor digiti minimi atrophy on MRI of the foot. Skeletal Radiol. 2008; 37:505-10.
9 Donovan A, Rosenberg ZS, Cavalcanti CF. MR imaging of entrapment neuropathies of the lower extremity. Part 2. The knee, leg, ankle, and foot. Radiographics. 2010; 30:1001-1019.
10 Baxter DE. Release of the nerve to the abductor digiti minimi. In: Kitaoka HB, ed. Master techniques in orthopaedic surgery of the foot and ankle. Philadelphia, PA: Lippincott Williams and Wilkins; 2002: 359.
11 Lui, TH. Endoscopic decompression of the first branch of the lateral plantar nerve. Arch Orthop Trauma Surg 2007; 127:859-61.
12 Stanczak JD, McLean VA, Yao L. Atrophy of the abductor minimi muscle: marker of neuropathic heel pain syndrome. (abstr) Radiology 2001; 221(P): 522.
13 Schon LC, Glennon TC, Baxter DE. Heel pain syndrome: electrodiagnostic support for nerve entrapment. Foot Ankle 1993; 14:129-135.
14 Alshami AM, Souvlis T, Coppieters MW. A review of plantar heel pain of neural origin: differential diagnosis and management. Manual Therapy 2008; 13:103-111.
15 Louisia S, Masquelet AC. The medial and inferior calcaneal nerves: an anatomic study. Surg Radiol Anat 1999; 21:169-173.
16 Govsa F, Bilge O, Ozer A. Variations in the origin of the medial and inferior calcaneal nerves. Arch Orthop Trauma Surg 2006; 126:6-14.
17 Hochman MG, Zilberfarb JL. Nerves in a pinch: imaging of nerve compression syndromes. Radiol Clin North Am. 2004; 42:221-245.
18 Kim SJ, Hong SH, Jun WS, et al. MR imaging mapping of skeletal muscle denervation in entrapment and compressive neuropathies. Radiographics. 2011; 31:319-32.
19 Fleckenstein JL, Watumull D, Conner KE, et al. Denervated human skeletal muscle: MR imaging evaluation. Radiology. 1993; 187:213-8.
20 Henricson AS, Westlin NE. Chronic calcaneal pain in athletes: entrapment of the calcaneal nerve? Am J Sports Med 1984; 12:152-154.
21 Baxter DE, Pfeffer GB. Treatment of chronic heel pain by surgical release of the first branch of the lateral plantar nerve. Clin Orthop 1992; 279:229-236.
22 Cozzarelli J, Sollitto RJ, Thapar J, Caponigro J. A 12-Year Long-Term Retrospective Analysis of the Use of Radiofrequency Nerve Ablation for the Treatment of Neurogenic Heel Pain. Foot Ankle Spec; 2010 3:338-346.
23 Mesmar M, Amarin Z, Shatnawi N, Bashaireh K. Chronic heel pain due to the entrapment of the first branch of the lateral plantar nerve: analysis of surgical treatment. Eur J Orthop Surg Traumatol 2010; 20:563-567.
24 Goecker RM, Banks AS. Analysis of release of the first branch of the lateral plantar nerve J Am Podiatr Med Assoc 2000; 90:281-286.
What is Baxter's nerve entrapment? Baxter's nerve entrapment occurs when a small nerve (known as Baxter's nerve or, more specifically, the first branch of the lateral plantar nerve) becomes pinched (impinged) between two muscles of the inner foot.
Baxter's nerve entrapment is responsible for 20% of chronic heel pain cases. Since the condition is often overlooked and misdiagnosed as plantar fasciitis, it is common for treatment to be delayed and the pain to last for months or even years.
The inferior calcaneal nerve or Baxter's nerve is the first branch of the lateral plantar nerve. It innervates the abductor digiti quinti muscle. Entrapment of this nerve has been implicated as a cause of anterior heel pain (Baxter and Pfeffer, 1992; Schon et al., 1993; Park and Del Toro, 1996).
Surgical Treatment Options:
When pain levels fail to improve with conservative treatment or cease for a short time after injection therapy only to return, surgery for Baxter's Nerve Entrapment known as neurolysis may be indicated and may also be combined with a plantar fascia release.
If a nerve is pinched for only a short time, there's usually no permanent damage. Once the pressure is relieved, nerve function returns to normal. However, if the pressure continues, chronic pain and permanent nerve damage can occur.
The most frequently recommended treatment for a pinched nerve is rest for the affected area. Your doctor will ask you to stop any activities that cause or aggravate the compression. Depending on the location of the pinched nerve, you may need a splint, collar or brace to immobilize the area.
The most common complaint in the foot and ankle region is heel pain. The most of these problems, however, are related to plantar fasciitis. Up to 20% of cases of chronic heel pain are caused by Baxter's nerve entrapment. However, it's an often-overlooked source of heel pain.
Six weeks after surgery, patients may resume full activity. With mild and/or intermittent symptoms, relief of numbness, tingling, and pain is often immediate. With long-standing or severe cases, relief of symptoms and return of muscle function may be more gradual and over the course of many months.
physical exam the heel by palpating the proximal and distal plantar fascia. palpate and percuss the tibial and medial calcaneal nerve. palpate the abductor hallucis origin. clinically, to differentiate baxter's nerve entrapment from other heel pain.
Lateral plantar nerve entrapment has similar symptoms to Plantar fasciitis and Tarsal tunnel syndrome. These include: Pain over the inside of the ankle and heel. Pressing in (palpating) along the inside of your foot and ankle, especially near the heel bone may reproduce symptoms.
The most common cause for LPN was trauma and the most common site of injury was at the passage of the lateral plantar nerve through the abductor tunnel at the instep of the foot.
- Take care of your feet, especially if you have diabetes. Check daily for blisters, cuts or calluses. ...
- Exercise. ...
- Quit smoking. ...
- Eat healthy meals. ...
- Avoid excessive alcohol. ...
- Monitor your blood glucose levels.
Your surgeon can remove the damaged section and reconnect healthy nerve ends (nerve repair) or implant a piece of nerve from another part of your body (nerve graft). These procedures can help your nerves regrow.
- Maintain a healthy weight. Extra weight can put extra stress on your plantar fascia.
- Choose supportive shoes. Buy shoes with a low to moderate heel, thick soles, good arch support and extra cushioning. ...
- Don't wear worn-out athletic shoes. ...
- Change your sport. ...
- Apply ice. ...
- Stretch your arches.
That said, a trapped nerve can be excruciatingly painful. In some instances pain can be so severe that movement is utterly impossible, and people can get “stuck” in one position.
When symptoms of cervical radiculopathy persist or worsen despite nonsurgical treatment, your doctor may recommend surgery. The primary goal of surgery is to relieve your symptoms by decompressing, or relieving pressure on, the compressed nerves in your neck. Other goals of surgery include: Improving neck pain.
Nerve impingement, known to some as a pinched nerve, occurs where there is too much pressure applied to a nerve by surrounding tissues such as bone, tendon, cartilage, or muscles.
Nerve impingement, or nerve entrapment, indicates that one single nerve is directly compressed. This occurs in the peripheral nerves that have branched out from the spinal cord and spinal nerve roots. Nerve root encroachment refers to the crowding of the space in and around the spinal column through which nerves pass.
Physical therapy as a method of treating pinched nerve is more effective than other non-surgical methods like administering drugs and steroidal injections because the former brings about much more than just pain relief.
If you believe you may be suffering from a pinched nerve, you should always visit an orthopedic surgeon near you to ensure that is the problem and rule out any more serious spinal issues. These doctor visits can also help determine if a more chronic ailment, like spinal arthritis, is to blame.
Gradual onset of numbness, prickling or tingling in your feet or hands, which can spread upward into your legs and arms. Sharp, jabbing, throbbing or burning pain. Extreme sensitivity to touch.
A person may experience pain on the bottom of the foot that worsens when walking, particularly in tight high heels. The pain may fade during rest or after removing the shoes. The pain may be burning, stabbing, or tingling, or it may feel like an electric shock.
Pinched nerves occur when excessive pressure is placed on a nerve by the surrounding tissues. This can happen in the feet due to an injury, from wearing poorly fitted shoes, or from having flat feet, bone spurs, or arthritis, among many other possible causes.
Keep your foot or feet elevated as much as possible. This is especially important in the first 48 hours. IT IS IMPORTANT TO WALK AT LEAST 40 TO 50 FEET PER HOUR TO KEEP THE NERVES FROM GETTING STUCK IN SCAR TISSUE.
According to Spine-Health, the success rate of pinched nerve surgery is high, with approximately 90 percent of patients experiencing relief of pain. A majority of patients with acute or severe back pain can benefit more from a microdiscectomy or laminectomy.
The operation is carried out under general anaesthetic, which means you'll be asleep during the procedure and won't feel any pain. The whole operation takes at least an hour, but it may take much longer, depending on its complexity. The exact level of decompression required will be determined using an X-ray.
Nerve conduction studies, including an Electromyogram (EMG) may be performed on individuals suffering with nerve pain symptoms. These studies use electrical impulses to determine the level of damage. A final diagnosis will be made by your physician through the help of one or all of these tests.
Foot and ankle neuropathy and nerve entrapment symptoms
Numbness. Sharp or burning pain. Tingling sensations or feeling that your foot has fallen “asleep” Weakness in your foot, toes or ankle.
Patients suffering from plantar fasciitis typically have pain directly beneath the heel bone where the plantar fascia attaches. In the case of Baxter's neuritis, the pain on examination is higher on the foot and more to the inside, rather than the bottom—where the nerve is actually inflamed or entrapped.
Your doctor may suggest a combination of NSAIDs, physical therapy, and rest. Another possible nonsurgical approach is injection therapy. Cortisone injections may help reduce inflammation and remove the pressure on your nerve, and stem cellinjections may help your body heal.
- Rest. Many of the conditions that cause leg and foot numbness, such as nerve pressure, improve with rest.
- Ice. Ice can help reduce swelling that can put pressure on nerves. ...
- Heat. ...
- Massage. ...
- Exercise. ...
- Supportive devices. ...
- Epsom salt baths. ...
- Mental techniques and stress reduction.
Treatment may include injecting anesthetics, steroids, or anti-scarring materials at the entrapment points. In some cases, surgery can be performed on the affected area. In addition, avoiding the repetitive behaviors that cause the entrapment can help.
- numbness and tingling in the feet or hands.
- burning, stabbing or shooting pain in affected areas.
- loss of balance and co-ordination.
- muscle weakness, especially in the feet.
Plantar fasciitis typically causes a stabbing pain in the bottom of your foot near the heel. The pain is usually the worst with the first few steps after awakening, although it can also be triggered by long periods of standing or when you get up from sitting.
Plantar fasciitis usually causes an achy pain in your heel or along the bottom of your foot. The pain can change depending on what you're doing or the time of day. Some types of pain you might feel include: Pain when you stand up after sleeping or sitting down.
Tramadol. Tramadol is a powerful painkiller related to morphine that can be used to treat neuropathic pain that does not respond to other treatments a GP can prescribe. Like all opioids, tramadol can be addictive if it's taken for a long time.
Nervive Pain Relieving Cream is formulated with maximum strength levels of Lidocaine HCL and Menthol to block nerve pain signals. Feel the non-greasy pain relieving cream start working in less than 5 minutes.
Berries, peaches, cherries, red grapes, oranges and watermelon, among others, are loaded with antioxidants, which help to decrease inflammation and reduce nerve damage. Plus, grapes, blueberries and cranberries have been found to be full of a powerful anti-inflammatory compound called resveratrol.
Nerve damage. Temporary facial flushing. Temporary flare of pain and inflammation in the joint. Temporary increase in blood sugar.
Does an MRI scan show nerve damage? A neurological examination can diagnose nerve damage, but an MRI scan can pinpoint it. It's crucial to get tested if symptoms worsen to avoid any permanent nerve damage.
As a specialist in peripheral nerve surgery, Dr. Seruya wants his patients to know that after a period of 12-18 months nerve damage can become permanent.
Cortisone does not replace the need for supportive shoes, foot orthoses, calf stretching, and other physical measures. Cortisone is typically injected at 2 month intervals, until the condition resolves or 3 injection have been administered, whichever comes first.
Far from being a permanent or chronic condition, plantar fasciitis typically responds well to treatment. Most people recover completely with a few months of conservative treatment. And, you have lots of options available to you. Many cases of plantar fasciitis respond positively to conservative treatment strategies.
Experts suggest that you try at least 6 months of other treatment before you consider surgery. Surgery may be right for you if you keep having bad heel pain after 6 to 12 months of home treatment. You might also think about surgery if heel pain is affecting your ability to work or do moderate exercise.
Symptoms of Pinched Nerves
Pain in the area of compression, such as the neck or low back. Radiating pain, such as sciatica or radicular pain. Numbness or tingling. "Pins and needles" or a burning sensation.
In many cases, the cause is a herniated disk slipping out between vertebrae in the spinal cord and pressing on the spinal nerve that goes down the leg. Most pinched nerves originate in the neck (cervical radiculopathy), upper middle back (thoracic radiculopathy) or lower back (lumbar radiculopathy).
Background: Baxter's neuropathy is a nerve entrapment syndrome that results from the compression of the inferior calcaneal nerve. The causes of Baxter's neuropathy include altered foot biomechanics such as flatfoot, plantar calcaneal enthesophytes, and plantar fasciitis.
Pinched Nerve Pain is Usually Short-Lived
In most cases, symptoms improve and nerve function resumes to normal within 6 to 12 weeks of conservative treatment. Conservative treatment options include physical therapy, and non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen.
The compression of a spinal nerve root due to a herniated disc is one of the most common examples of a pinched nerve. A pinched nerve is also referred to as nerve compression, nerve impingement, nerve root encroachment, radiculopathy and/or sciatica.
Compression of the root nerve in the back is one of the few physical disorders of back pain that are counted as disability in the Blue Book of Impairments.
Qualifying for Disability Due to Spinal Nerve Root Compression. The Social Security Administration (SSA) recognizes that severe nerve root compression can be debilitating, and as a result, the agency has created an official impairment listing in its "Blue Book" of impairments.
If your history and symptoms suggest a pinched nerve, tests such as these can confirm the diagnosis: Electromyography and nerve conduction studies: These tests measure the electrical signals in your muscles and can indicate whether you have nerve damage.
- Braces or splints. These devices keep the affected limb, fingers, hand or foot in the proper position to improve muscle function.
- Electrical stimulator. Stimulators can activate muscle served by an injured nerve while the nerve regrows. ...
- Physical therapy. ...
- Take care of your feet, especially if you have diabetes. Check daily for blisters, cuts or calluses. ...
- Exercise. ...
- Quit smoking. ...
- Eat healthy meals. ...
- Avoid excessive alcohol. ...
- Monitor your blood glucose levels.