Baxter’s neuritis is a condition causing heel pain, often mistaken for more common foot problems. It involves the irritation or compression of a specific nerve in the foot, leading to discomfort that can affect daily activities. Understanding this condition is key to finding relief.
Understanding Baxters Neuritis
Baxter’s neuritis, also known as Baxter’s nerve entrapment, is a condition where the inferior calcaneal nerve becomes compressed. This nerve is the first branch of the lateral plantar nerve, originating from the tibial nerve in the ankle. It extends along the inside of the heel, providing sensation to parts of the foot and motor innervation to the abductor digiti minimi muscle.
The entrapment occurs in one of two locations: either between the deep fascia of the abductor hallucis muscle and the quadratus plantae muscle, or near the medial calcaneal tuberosity where the nerve can be pressed against bone or bone spurs. This compression leads to inflammation and irritation of the nerve, resulting in chronic heel pain.
Recognizing the Symptoms
Individuals with Baxter’s neuritis experience a sharp or burning pain, primarily on the inner side of the heel. This discomfort can extend into the arch of the foot, sometimes accompanied by numbness or tingling sensations. Unlike plantar fasciitis, which causes severe “first-step” pain in the morning that lessens with activity, Baxter’s neuritis pain worsens throughout the day and with prolonged activity like standing, walking, or running.
The pain may also be felt higher on the foot and more towards the inside, rather than directly on the bottom of the heel. Tenderness is localized along the inner heel. Sometimes, weakness in the abductor digiti minimi muscle, which the nerve supplies, may be present.
Causes and Risk Factors
Several factors can contribute to the development of Baxter’s neuritis, leading to the compression of the inferior calcaneal nerve:
Anatomical predispositions, such as flat feet (pes planus) or high arches (pes cavus), which can cause excessive strain or pressure on the nerve.
A tight abductor hallucis muscle fascia or its close proximity to the medial calcaneal tuberosity.
Repetitive stress from activities like prolonged standing, running, or high-impact sports, which can inflame and swell the area.
Improperly fitting footwear, especially shoes lacking adequate arch support or having a tight toe box.
Bony growths called heel spurs, which can press directly on the nerve.
Conditions like obesity and chronic plantar fasciitis, which increase stress on the foot or cause inflammation affecting the nerve.
Diagnosis and Treatment
Diagnosis of Baxter’s neuritis begins with a thorough physical examination, where a healthcare professional assesses tenderness, foot alignment, and pain response to nerve compression. While a physical exam can be challenging for detecting inferior calcaneal nerve compression, pain may be felt along the arch or on the outer aspect of the bottom of the foot where the abductor digiti minimi muscle is located. Imaging studies, such as X-rays, are used to rule out other bone-related issues like fractures or heel spurs.
Magnetic Resonance Imaging (MRI) or ultrasound can help identify nerve inflammation, soft tissue compression, or structural abnormalities, and may show changes in muscle due to nerve damage. Sometimes, an ultrasound-guided injection of a local anesthetic near the nerve’s origin can serve as a diagnostic test; if pain decreases, Baxter’s entrapment is likely.
Treatment begins with conservative approaches aimed at reducing nerve compression and inflammation. These include:
Rest, applying ice, and taking non-steroidal anti-inflammatory drugs (NSAIDs) to manage pain and swelling.
Physical therapy, with stretching exercises for the plantar fascia and calf muscles, to improve flexibility and reduce tension.
Custom orthotics or supportive footwear with proper arch support, recommended to correct foot biomechanics and redistribute pressure.
Corticosteroid injections around the nerve to provide relief from pain and inflammation.
If conservative treatments do not provide relief, surgical intervention may be considered. Procedures like nerve decompression surgery involve making a small incision to release the entrapped nerve. If a heel spur is the cause of compression, its removal may be necessary. Recovery after surgery involves initial rest and limited weight-bearing for a few weeks, followed by a gradual return to activity with physical therapy.