Hereditary sensory motor neuropathy (HSMN)

Hereditary sensory motor neuropathy (HSMN) constitutes a cluster of inherited disorders that target the peripheral nervous system, leading to the gradual deterioration of both motor and sensory nerves.

Among these conditions are genetic ailments like Charcot-Marie-Tooth disease and peroneal muscular atrophy, each presenting its own set of challenges that significantly influence individuals' daily functioning.

Our team of neuro specialists at Advocate Health Care provide insights into HSMN, devising a personalized treatment plan aimed at helping you manage this condition effectively and enhancing your overall quality of life.

Types of hereditary motor sensory neuropathy

Hereditary motor sensory neuropathy symptoms

Hereditary motor sensory neuropathy has a range of symptoms that affect both sensory and motor functions. HSMN symptoms can vary in severity and presentation but include disturbances in sensation and movement.

Motor symptoms

Motor symptoms of HSMN typically present themselves as weakness, muscle wasting and difficulties with coordination and balance.

Affected individuals may have trouble walking, running or performing tasks that require fine motor skills. Muscle weakness can progress over time and may lead to significant impairments in mobility.

Sensory symptoms

Sensory symptoms of HSMN often involve changes to feeling and perception. If you have HSMN, you may experience:

• Numbness
• Tingling sensations
• Reduced ability to feel pain or temperature changes

Sensory symptoms can affect various parts of the body, including the hands, feet and limbs.

While certain symptoms may be common, such as sensory abnormalities and muscle weakness, the severity and how they present themselves can vary widely.

Hereditary motor sensory neuropathy symptoms

Hereditary motor sensory neuropathy has a range of symptoms that affect both sensory and motor functions. HSMN symptoms can vary in severity and presentation but include disturbances in sensation and movement.

Motor symptoms

Motor symptoms of HSMN typically present themselves as weakness, muscle wasting and difficulties with coordination and balance.

Affected individuals may have trouble walking, running or performing tasks that require fine motor skills. Muscle weakness can progress over time and may lead to significant impairments in mobility.

Sensory symptoms

Sensory symptoms of HSMN often involve changes to feeling and perception. If you have HSMN, you may experience:

• Numbness
• Tingling sensations
• Reduced ability to feel pain or temperature changes

Sensory symptoms can affect various parts of the body, including the hands, feet and limbs.

While certain symptoms may be common, such as sensory abnormalities and muscle weakness, the severity and how they present themselves can vary widely.

Diagnosis of hereditary motor sensory neuropathy

Diagnosing HSMN involves a combination of a physical exam, review of your medical history and symptoms, neurological tests and digital imaging.

Your provider will begin by taking a detailed medical history, including symptoms experienced and any family history of neurological and genetic disorders. During your physical exam, your provider will perform a neurological exam to assess muscle strength, sensation, reflexes and coordination.

Your provider may recommend nerve function and imaging tests to identify the type, location and extent of any nerve damage. In rare cases, a nerve biopsy may be recommended to examine a small sample of nerve tissue under a microscope.

Genetic testing

Genetic testing can confirm the presence of specific gene mutations associated with HSMN, such as mutations in genes related to Charcot-Marie-Tooth disease or peroneal muscular atrophy. Genetic testing may involve taking blood samples or other tissue samples to identify mutations.

Nerve function tests

• Electromyography (EMG): A electromyography test evaluates the electrical activity of muscles. It can help differentiate between muscle disorders and nerve disorders by detecting abnormalities in muscle response to nerve stimulation.
• Nerve conduction studies (NCS): NCS are commonly used to assess the function of peripheral nerves. This test involves applying small electrical shocks to nerves and recording the speed and strength of the nerve signals. Abnormalities in nerve conduction can indicate nerve damage, a characteristic of HSMN.

Imaging tests

• MRI: An MRI of the spine can reveal tumors or nerve root compression, also known as a pinched nerve, that could be causing your peripheral neuropathy.
• CT scan: CT scans of the spine can show herniated discs, spinal stenosis (narrowing of the spinal canal), tumors and bone irregularities that may affect nerves.

Treatment for hereditary motor sensory neuropathy

While there is no cure for HMSN, various interventions and therapies can help alleviate symptoms and slow disease progression.

Treatment for HMSN is a multidisciplinary approach and may involve a physical therapist, neurologist, orthopedic specialist, and a mental health provider. Your care team will focus on managing symptoms, improving functions, and enhancing quality of life.

Some common HMSN treatment options include:

• Mobility aids: Assistive devices such as canes, walkers, or wheelchairs may be necessary for individuals with significant mobility impairments.
• Occupational therapy: Occupational therapy focuses on maximizing independence and function in daily activities.
• Pain management: Pain management strategies may include over-the-counter pain medications such as ibuprofen or naproxen or prescription medications such as antidepressants or anti-seizure medications.
• Physical therapy: Physical therapy plays a crucial role in managing HMSN by improving muscle strength, flexibility, and coordination.
• Using orthotic devices: Orthotic devices such as braces and splints can provide support and stability, helping to improve gait and function.

Your care team will work together to address symptoms comprehensively and focus on individualized care.

Living with hereditary sensory motor neuropathy

There are many challenges you’ll face while living with HSMN. However, with proper management and support, you can lead a fulfilling life.

While HSMN is a progressive condition, the long-term outlook varies depending on the specific type of HSMN you have and individual factors. Some individuals may experience mild symptoms that remain stable over time, while others may face more significant challenges with mobility and function.

Early intervention is crucial in managing HSMN effectively. Your care team at Advocate Health Care will be with you every step of the way and help address your individual needs.