Anterior Tarsal Syndrome

Introduction

Anterior tarsal tunnel syndrome is a relatively rare but significant condition that affects the upper part of the foot due to compression of the deep peroneal nerve. This nerve is responsible for the sensory innervation of the region, running along the upper part of the foot to provide sensation to the toes and surrounding areas. When compressed or irritated, this nerve can cause a series of disturbing symptoms that can affect the patient’s quality of life.

The causes of anterior tarsal tunnel syndrome are diverse and may include anatomical abnormalities, repetitive trauma, inappropriate footwear, local inflammation, and other factors. Anatomical abnormalities, such as ligamentous thickening or variations in the structure of the anterior tarsal canal, can contribute to nerve compression, as can repeated trauma related to certain physical activities. Wearing unsuitable shoes, especially those that put excessive pressure on the upper part of the foot, can also play a role in the development of this condition.

Symptoms of anterior tarsal tunnel syndrome are varied, but typically include localized pain, tingling, burning sensations, and sometimes numbness in the upper part of the foot. These symptoms may be exacerbated when walking, running, or other activities that put strain on the foot area. Sensitivity to touch may also be impaired, and the patient may experience significant discomfort or even a change in gait to avoid worsening symptoms.

Diagnosis of anterior tarsal tunnel syndrome is based on a thorough assessment of symptoms, the patient’s medical history, and specialized physical examinations. Imaging studies, such as magnetic resonance imaging (MRI) or ultrasound, can be used to visualize the internal structures of the foot and confirm nerve compression.

When it comes to treatment, approaches vary depending on the severity of symptoms. Conservative measures such as rest, wearing appropriate shoes, and using orthotics may be recommended initially. Anti-inflammatory medications may be prescribed to relieve pain and reduce inflammation. In some cases, corticosteroid injections may be considered to target local inflammation. If symptoms persist despite these measures, surgery to release the compressed nerve may be considered.

In conclusion, although anterior tarsal tunnel syndrome is a rare condition, it can have a significant impact on the patient’s daily life due to its debilitating symptoms. Management of this condition requires an individualized approach, taking into account the underlying causes and severity of symptoms, in order to optimize treatment results and improve the patient’s quality of life.

Causes

The causes of anterior tarsal tunnel syndrome are diverse and can be linked to anatomical, traumatic, inflammatory or mechanical factors. Here are some of the main causes associated with this condition:

1. Anatomical Abnormalities: Anatomical variations such as ligamentous thickenings, protruding bones, or other abnormalities in the anterior tarsal canal region can result in compression of the dorsal cutaneous nerve.
2. Repetitive Trauma: Repetitive trauma or microtrauma to the upper part of the foot, such as that occurring during sporting activities or improper footwear, can contribute to irritation and compression of the nerve.
3. Unsuitable Footwear: Wearing inappropriate footwear that is too tight or with features that place excessive pressure on the upper part of the foot may play a role in the development of anterior tarsal tunnel syndrome.
4. Local Inflammation: Inflammatory processes, such as synovitis or tenosynovitis, can cause swelling and increased pressure in the area, affecting the dorsal cutaneous nerve.
5. Intense Physical Activities: Certain intense or repetitive physical activities that stress the upper part of the foot, such as running or frequent jumping, can contribute to nerve compression.
6. Congenital Structural Abnormalities: Congenital structural abnormalities of the foot can predispose to nerve compression, thereby increasing the risk of developing anterior tarsal tunnel syndrome.
7. Hypertrophy of Muscles or Ligaments: Abnormal hypertrophy of muscles or anterior tarsal tunnel syndrome manifests with a range of symptoms that primarily affect the upper part of the foot. Symptoms characteristic of this condition may vary in intensity from person to person, but generally include the following:
8. Local Pain: Pain is the predominant symptom of anterior tarsal tunnel syndrome. Individuals may experience localized pain on the upper part of the foot, usually near the base of the toes or the metatarsal. This pain may be described as shooting, burning, or tingling.
9. Tingling and Burning Sensations: Patients may experience tingling or burning sensations along the top of the foot. These abnormal sensations may be intermittent or persistent.
10. Numbness: Some individuals may experience a feeling of numbness in the affected area. The numbness may be more pronounced during certain activities, including walking or standing for prolonged periods.
11. Sensitivity to Touch: The affected area may become more sensitive to touch. Mild stimuli, such as shoe pressure or friction, can trigger or intensify pain.
12. Worsening with Activity: Symptoms of anterior tarsal tunnel syndrome tend to worsen during activities that put strain on the foot area, such as walking, running, or flexing the foot.
13. Swelling: In some individuals, slight swelling of the upper part of the foot may be observed. The swelling is often associated with inflammation resulting from compression of the nerve.
14. Gait Modification: In response to pain and discomfort, some individuals may modify their gait to avoid putting too much pressure on the affected area, which can lead to changes in the way they walk.

Pathophysiology

The pathophysiology of anterior tarsal tunnel syndrome is based on compression of the dorsal cutaneous nerve of the foot within the anterior tarsal tunnel. Understanding the underlying mechanisms helps explain the specific symptoms associated with this condition. Here are the main aspects of the pathophysiology of anterior tarsal tunnel syndrome:

1. Anatomy of the Anterior Tarsal Canal: The anterior tarsal canal is a bony structure located on the upper part of the foot. It houses the dorsal cutaneous nerve, which is responsible for sensory innervation of the upper part of the foot, including the toes.
2. Nerve Compression: Dorsal cutaneous nerve compression can occur due to various factors, such as anatomical abnormalities, degenerative changes, repeated trauma, or local inflammation. This compression leads to an impairment of the normal function of the nerve.
3. Irritation and Inflammation: Compression of the dorsal cutaneous nerve can cause irritation and inflammation of the nerve fiber. This inflammation can increase the sensitivity of the nerve, contributing to pain, tingling, and other abnormal sensations.
4. Nervous Ischemia: Prolonged compression of the nerve can result in decreased blood supply to the nerve fiber, causing ischemia. Ischemia can worsen symptoms and contribute to deterioration of nerve function.
5. Abnormal Nervous Responses: In response to compression, the dorsal cutaneous nerve can send abnormal nerve signals to the brain, interpreted as sensations of pain, tingling, or numbness. These signals can be exacerbated during physical activity or other situations that put stress on the foot.
6. Changes in Skin Sensitivity: Compression of the dorsal cutaneous nerve can cause changes in skin sensitivity on the upper part of the foot. Some individuals may experience hypersensitivity, while others may experience a decrease in sensation.

Diagnosis and Treatment

Diagnosis of Anterior Tarsal Tunnel Syndrome:

1. History: The doctor collects detailed information about the patient’s medical history, specific symptoms, precipitating factors, and duration of symptoms.
2. Clinical Examination: A thorough physical examination is performed to assess tenderness, pain, mobility, and possible signs of nerve compression in the upper part of the foot.
3. Neurological Tests: Neurological tests may be performed to assess nerve function, including skin sensitivity, reflexes and muscle strength.
4. Medical Imaging: Imaging studies, such as magnetic resonance imaging (MRI) or ultrasound, can be used to visualize the internal structures of the foot, identify nerve compression, and rule out other potential causes of symptoms.

Treatment of Anterior Tarsal Tunnel Syndrome:

1. Conservative Measures:
   • Rest and Elevation: Resting and elevating the foot can help reduce inflammation and relieve nerve compression.
   • Proper Footwear: Wearing well-fitting, supportive shoes is essential to minimize pressure on the upper part of the foot.
2. Drugs :
   • Nonsteroidal anti-inflammatory drugs (NSAIDs): These may be prescribed to reduce inflammation and relieve pain.
   • Analgesics: Analgesic medications may be used for symptomatic relief.
3. Orthotics and Aids: Custom orthotics may be recommended to support the foot and reduce pressure on the nerve. Protective pads or splints may also be used.
4. Corticosteroid Infiltrations: Corticosteroid injections may be considered to reduce local inflammation and relieve symptoms.
5. Physical Therapy: Specific exercises may be prescribed to strengthen muscles, improve stability and promote mobility of the foot.
6. Surgical Intervention: In cases of severe nerve compression or when conservative treatments fail, surgical release of the dorsal cutaneous nerve may be considered.

Conclusion

In conclusion, anterior tarsal tunnel syndrome represents a specific pathology of the foot, defined by compression of the dorsal peroneal nerve. This condition causes a variety of symptoms affecting the upper part of the foot, such as pain, tingling, burning sensations and numbness. The pathophysiology of this condition involves compression of the nerve, often attributable to anatomical factors, trauma or local inflammation.

Diagnosis of anterior tarsal tunnel syndrome requires a thorough evaluation including a medical history, a detailed physical examination, and sometimes imaging studies to confirm nerve compression. In terms of treatment, varied approaches, ranging from conservative measures to more invasive interventions, are available depending on the severity of symptoms and the patient’s response to treatments.

Successful management of this pathology relies on an individualized approach, taking into account the diversity of contributing factors and clinical presentations. Close collaboration between healthcare professionals and the patient is crucial to develop an optimal treatment plan and improve the quality of life of the patient affected by anterior tarsal tunnel syndrome.

In short, in-depth understanding of the pathophysiology, early diagnosis and implementation of appropriate therapeutic strategies are essential for effective management of this specific foot condition. Continuing research in the medical field helps expand our knowledge and refine diagnostic and therapeutic approaches to optimize outcomes in patients with anterior tarsal tunnel syndrome.

References

1. Calvo-Lobo C, Painceira-Villar R, López-López D, García-Paz V, Becerro-de-Bengoa-Vallejo R, Losa-Iglesias ME, Palomo-López P.  Tarsal  Tunnel  Mechanosensitivity Is Increased in Patients with Asthma: A Case-Control Study. J Clin Med. 2018 Dec 12;7(12) [ PMC free article ] [ PubMed ]2.
2. Stødle AH, Molund M, Nilsen F, Hellund JC, Hvaal K. Tibial Nerve Palsy After Lateralizing Calcaneal Osteotomy. Foot Ankle Spec. 2019 Oct;12(5):426-431. [ PubMed ]3.
3. Zuckerman SL, Kerr ZY, Pierpoint L, Kirby P, Than KD, Wilson TJ. An 11-year analysis of peripheral nerve injuries in high school sports. Phys Sportsmed. 2019 May;47(2):167-173. [ PubMed ]4.
4. Rinkel WD, Castro Cabezas M, van Neck JW, Birnie E, Hovius SER, Coert JH. Validity of the Tinel Sign and Prevalence of Tibial Nerve Entrapment at the  Tarsal  Tunnel  in Both Diabetic and Nondiabetic Subjects: A Cross-Sectional Study. Plast Reconstruction Surg. 2018 Nov;142(5):1258-1266. [ PubMed ]5.
5. Hong CH, Lee YK, Won SH, Lee DW, Moon SI, Kim WJ. Tarsal  tunnel  syndrome  caused by an uncommon ossicle of the talus: A case report. Medicine (Baltimore). 2018 Jun;97(25):e11008. [ PMC free article ] [ PubMed ]6.
6. Komagamine J. Bilateral  Tarsal  Tunnel  Syndrome . Am J Med. 2018 Jul;131(7):e319. [ PubMed ]7.
7. Schuh A, Handschu R, Eibl T, Janka M, Hönle W. [ Tarsal  tunnel  syndrome ]. MMW Fortschr Med. 2018 Apr;160(6):58-59. [ PubMed ]8.
8. Mansfield CJ, Bleacher J, Tadak P, Briggs MS. Differential examination, diagnosis and management for tingling in toes: fellow’s case problem. J Man Manip Ther. 2017 Dec;25(5):294-299. [ PMC free article ] [ PubMed ]9.
9. Tu P. Heel Pain: Diagnosis and Management. Am Fam Physician. 2018 Jan 15;97(2):86-93. [ PubMed ]