yogabook / pathologie / morton’s neuralgia

Morton’s neuralgia / neuroma / metatarsalgia

Definition of

compression-induced reactive swelling of interdigital nerves and their fasciae (perineural fibrosis), which become inflamed in the area of the metatarsal heads. Morton’s neuroma is therefore a nerve compression syndrome. It is characterized by water retention and scarring after inflammation. Morton’s neuroma is the main cause of metatarsalgia and the main cause of metatarsalgia in women. In men, it mainly affects runners who run a lot. Runners are generally affected more frequently. Morton’s neuroma occurs most frequently between the 3rd and 4th rays, and less frequently between the 2nd and 3rd rays. Morton’s neuroma can occur between several beams and also on both sides. Smaller neuromas can remain asymptomatic. W:M 5:1, in 20% on both sides. Morton’s neuromas are often asymptomatic, which is the case in 1/3 of Americans. The transverse arch flattens, especially in splayfoot, and the interdigital nerves can be compressed (entrapment). Neighboring bursae can become entrapped. There are various theories about the exact pathomechanisms. Practice shows that Morton’s neuroma is often overlooked as the cause of metatarsalgia. In MRI they are recognizable from approx. 0.3 cm in size. Depending on the situation, it can be treated up to approx. 0.6 / 0.8 without neurectomy.

ICD G57.6

Cause

1. Splayfoot
2. Perineural fibrosis
3. Vascular proliferation
4. Traumatic contributory causation
5. Intraneural sclerohyalinosis (additional protein is deposited in the nerve)

Predisposing

– Behavior

1. inadequate footwear, especially with high heels or constricting the forefoot, which promotes the development of splayfoot
2. Possibly frequent running
3. prolonged standing
4. Forefoot running or conversion to it

– Musculoskeletal system

1. Splayfoot as a result of flatfoot, fallen arches or hollow foot
2. Hallux valgus
3. Existing arthrosis in the foot
4. Increased pressure load due to reduced flexibility in the OSG, e.g. after supination trauma

– Other factors

1. Overweight

Diagnosis

1. MRI
2. Disappearance of symptoms after local anesthesia
3. Tests and signs: Mulder sign, Gänsslen handgrip, interdigital nerve stretch test

Symptoms

1. Usually begins with pain only after prolonged loading of the foot in the shoe. It usually disappears after the load is removed and the shoe is taken off.
2. Sensitivity disorders in the ball of the toes
3. „Formication in the toe“, tingling
4. „Pea in the shoe feeling“
5. Numbness of the toe(s)
6. furry feeling
7. Later: acute, shooting, burning or stabbing pain, sometimes as far as the toes, which forces you to stop exercising or take off your shoes.
8. later: clicking phenomenon or „snapping“ in the foot. At this stage, pain and neurological abnormalities are usually permanent
9. NO pain at rest or start-up pain, both clearly speak against a Morton’s neuroma
10. Injection with local anesthetic improves in the short term

Therapy

1. Causal (against the causative splayfoot)
2. Training the intrinsic foot muscles and calf muscles only up to the pain threshold
3. Gang school
4. Relieving insert
5. Injection with cortisone and local anesthetic
6. Shock wave therapy, ultrasound, phonophoresis
7. local cryotherapy
8. Iontophoresis
9. Local infiltrations, allopathic or homeopathic
10. Splayfoot tape
11. For runners: reduced sprinting at the beginning, strength and technique training, avoid forefoot running
12. Surgery if necessary: repositioning surgery (nerve decompression) or neurectomy (from approx. 8 mm)