Inflammation of the nerve in the left leg causes symptoms and treatment

Inflammation of the left leg nerve is a health condition that can significantly affect a person's ability to move and perform daily activities, particularly when accompanied by persistent pain, numbness, tingling, or a burning sensation extending from the lower back to the thigh, leg, and foot.The severity of symptoms may vary from one person to another, depending on the affected nerve and the underlying cause. These causes may include a herniated disc, sciatica, peripheral nerve compression, or chronic conditions such as diabetes.The impact of this condition is not limited to pain alone. In some cases, it may progress to muscle weakness, difficulty walking, or loss of sensation in parts of the foot. This makes early diagnosis and choosing the appropriate treatment essential to prevent complications.What are the causes of left leg nerve inflammation? What are its most common symptoms and types? How can it be diagnosed and treated with medication, physical therapy, or surgery? And when does the pain become a warning sign that requires medical attention?We will explore all of this in this article on Dalili Medical.

1. What Is Left Leg Nerve Inflammation?

Problems affecting the nerves in the left leg refer to irritation, compression, or damage to one of the nerves responsible for sensation and movement in the leg. These problems may result from compression of the nerve roots extending from the lower spine to the foot or from peripheral neuropathy.

2. Is Left Leg Nerve Inflammation the Same as Sciatica?

No. Sciatica is a condition caused by irritation or compression of the sciatic nerve, whereas the term "leg nerve inflammation" is used to describe a group of conditions that may affect the sciatic nerve or other peripheral nerves.

3. Does Left Leg Nerve Inflammation Cause Lower Back Pain?

Yes. Problems affecting the nerves in the left leg may be accompanied by lower back pain, particularly when they result from compression of the lumbar nerve roots due to a herniated disc or spinal stenosis.

4. Does Left Leg Nerve Inflammation Cause Numbness and Burning?

Yes. Nerve irritation or damage may cause numbness, tingling, and burning sensations. These symptoms may extend to the toes, depending on the location of the affected nerve and the extent of the damage.

5. Is Left Leg Nerve Inflammation Dangerous?

Not necessarily. Many cases improve with proper diagnosis and treatment. However, certain symptoms may indicate a serious neurological problem, such as progressive muscle weakness, loss of bladder or bowel control, or numbness around the genital area. These symptoms require urgent medical evaluation.

6. How Long Does Recovery from Left Leg Nerve Inflammation Take?

Recovery time varies depending on the underlying cause, severity of the injury, and extent of nerve involvement. Mild cases may improve within a few weeks, while cases involving severe nerve compression or damage may take several months to recover. Some patients may continue to experience numbness or muscle weakness for a longer period.

7. Does Left Leg Nerve Inflammation Cause Muscle Weakness?

Yes. Damage to a nerve responsible for movement may lead to weakness in certain muscles of the thigh, leg, or foot. Patients may have difficulty lifting the foot, climbing stairs, or walking normally, depending on the location of the affected nerve and the extent of its involvement.

8. Can Left Leg Nerve Inflammation Be Prevented?

The risk of some conditions affecting the leg nerves can be reduced by maintaining a healthy weight, exercising regularly, avoiding prolonged sitting without movement, maintaining proper posture, controlling blood sugar levels, and treating vitamin deficiencies when diagnosed.

9. Does Left Leg Nerve Inflammation Affect Sleep?

Yes. Pain, burning, or numbness may worsen at night in some patients, making it difficult to fall asleep or causing frequent awakenings, particularly when symptoms are persistent or severe.

10. Does Left Leg Nerve Inflammation Affect Sensation in the Foot?

Yes. Nerve irritation or damage may lead to reduced sensation, tingling, or numbness in parts of the foot or toes. The location of these symptoms varies depending on which nerve is affected and where the damage occurs.

11. Can Symptoms of Left Leg Nerve Inflammation Return After Treatment?

Yes. Symptoms may return if the underlying cause persists or recurs, such as a recurrent herniated disc or continued pressure on the nerve. Therefore, it is important to treat the underlying cause, follow the doctor's instructions, and adhere to an appropriate rehabilitation program to reduce the risk of symptom recurrence.

Types of Nerve Problems Affecting the Left Leg

Problems affecting the nerves in the left leg vary depending on which nerve is affected and where the damage or irritation occurs. They may result from compression of the nerve roots emerging from the spine or injury to one of the peripheral nerves in the leg. The main conditions include:

1. Sciatic Nerve Irritation (Sciatica)

This occurs when the sciatic nerve becomes irritated or compressed. It may cause pain that starts in the lower back or buttocks and radiates through the thigh to the leg and foot. It may also be accompanied by numbness, tingling, or muscle weakness.

2. Peripheral Neuropathy

This condition affects the nerves outside the brain and spinal cord. It may involve the nerves in the left leg or multiple nerves throughout the body. Symptoms include numbness, tingling, burning sensations, and reduced sensation. Muscle weakness may also occur in some cases.

3. Lumbar Radiculopathy

This condition results from irritation or compression of the nerve roots emerging from the lumbar vertebrae in the lower back. It is often associated with a herniated disc or spinal canal stenosis. Symptoms may include pain radiating from the back down the leg, along with numbness or muscle weakness, depending on which nerve root is affected.

4. Common Peroneal Nerve Neuropathy

This condition affects the nerve responsible for certain movements of the foot and toes, as well as sensation in parts of the lower leg and foot. It may cause numbness along the outer part of the lower leg and the top of the foot, along with difficulty lifting the foot upward. This may lead to a condition known as foot drop.

5. Femoral Neuropathy

This condition affects the nerve responsible for sensation in the front of the thigh and certain movements of the knee joint. It may cause pain or numbness in the front of the thigh, as well as weakness in the muscles responsible for straightening the knee, making it difficult to climb stairs or walk.

6. Tibial Neuropathy

This condition affects the tibial nerve, which is responsible for certain foot movements and sensation in the sole. It may cause pain, burning, or numbness in the sole of the foot. These symptoms may result from nerve compression, as occurs in tarsal tunnel syndrome.

7. Sciatic Nerve Injury

The sciatic nerve itself may sustain a direct injury or become compressed along its course; the cause is not necessarily a problem involving the lumbar nerve roots. This may result in pain radiating down the leg, accompanied by numbness or weakness in some of the muscles of the leg and foot, depending on the location and severity of the injury.

Causes of Nerve Problems Affecting the Left Leg

There are several possible causes of pain and nerve problems in the left leg. These may result from compression of the nerve roots in the lower spine, injury to one of the peripheral nerves, or medical conditions that affect nerve function. The most common causes include:

1. Herniated Disc

A bulging or ruptured disc between the lumbar vertebrae may compress the nerve roots that extend toward the left leg. This can cause pain radiating down the leg, sometimes accompanied by numbness, tingling, or muscle weakness.

2. Sciatica

Sciatica occurs when the sciatic nerve or its nerve roots become irritated or compressed. It may cause pain that starts in the lower back or buttocks and radiates through the thigh, leg, and foot. It usually affects one side of the body.

3. Spinal Canal Stenosis

This condition occurs when the space within the spinal canal through which the nerves pass becomes narrowed. This may compress the nerves and cause pain, numbness, or weakness in the leg, particularly when standing or walking for extended periods.

4. Diabetes

Persistently high blood sugar levels may damage peripheral nerves, a condition known as diabetic neuropathy. It can cause numbness, burning, tingling, pain, and reduced sensation in the feet and legs.

5. Vitamin B12 Deficiency

Vitamin B12 deficiency can affect nerve health and function. It may cause numbness, tingling, and reduced sensation in the legs and feet. In some cases, it may also be accompanied by muscle weakness or balance problems.

6. Nerve Injuries

Falls, car accidents, sports injuries, or wounds may compress or damage nerves, causing pain, numbness, or muscle weakness in the area supplied by the affected nerve.

7. Nerve Compression Due to Certain Body Positions

Prolonged pressure on a nerve, such as sitting for extended periods with one leg crossed over the other or maintaining positions that compress the peroneal nerve near the knee, may cause numbness or tingling. Symptoms caused by temporary compression usually improve after changing position. However, persistent symptoms require medical evaluation.

8. Piriformis Syndrome

This condition may occur when the piriformis muscle, located in the buttock region, irritates or compresses the sciatic nerve. It can cause buttock pain that radiates to the back of the thigh and leg, sometimes accompanied by numbness or tingling.

9. Inflammatory and Autoimmune Diseases Affecting the Nerves

Certain autoimmune or inflammatory diseases may affect peripheral nerves, causing pain, numbness, or impaired sensation and movement. Symptoms vary depending on the type of disease and the nerves involved.

10. Certain Medications

Some medications may cause peripheral nerve damage as a side effect. Examples include certain chemotherapy drugs. Symptoms may include numbness, burning, tingling, or pain in the legs and feet.

Symptoms of Nerve Problems Affecting the Left Leg

The symptoms of nerve problems affecting the left leg vary depending on the affected nerve, the underlying cause, and the severity of the condition. They may appear as pain, sensory disturbances, or muscle weakness. The most common symptoms include:

1. Pain in the Left Leg

The patient may experience sharp or persistent pain in the left leg. It may start in the lower back or buttock area and radiate to the thigh, lower leg, and foot, particularly in cases of sciatic nerve irritation or compression of the lumbar nerve roots.

2. Numbness and Loss of Sensation

The patient may experience numbness, a loss of sensation, or reduced feeling in parts of the leg, foot, or toes, depending on the location of the affected nerve.

3. Recurrent Tingling

A pins-and-needles sensation may occur in the leg or foot. It may be intermittent or persistent.

4. Burning Sensation and Feeling of Heat

The patient may experience a burning sensation or a feeling of heat inside the left leg without any obvious external cause. This is a common symptom of certain types of peripheral neuropathy.

5. Electric Shock-Like Sensations

The patient may experience sudden pain that feels like an electric shock passing through the leg. It may radiate along the entire leg or occur in specific areas.

6. Leg Muscle Weakness

Damage to the nerves responsible for movement may weaken certain muscles in the thigh, lower leg, or foot. This may make it difficult to lift the foot, move the toes, or stand normally.

7. Increased Pain With Certain Movements and Positions

Pain may worsen when walking, bending, or sitting for prolonged periods. It may also become more severe when coughing or sneezing in some cases involving compression of the nerve roots.

8. Difficulty Walking and Moving

Severe pain, muscle weakness, or sensory disturbances may make it difficult to walk, climb stairs, or maintain balance. In more severe cases, the patient may need support while moving.

9. Changes in Skin Sensation

The patient may notice increased sensitivity to touch or reduced sensation in certain areas of the leg. Touching the skin may cause pain, or the patient may fail to notice light touches because of reduced sensation.

Medication Treatment for Nerve Problems Affecting the Left Leg

Medication treatment depends on the underlying cause of the symptoms, the severity of the pain, and the extent of nerve involvement. Treatment may aim to relieve pain, reduce inflammation in certain cases, or manage the condition responsible for affecting the nerves. The main types of medications a doctor may recommend include:

First: Pain Relievers and Anti-Inflammatory Medications

Certain pain relievers and nonsteroidal anti-inflammatory drugs (NSAIDs) may be used to relieve pain, particularly when it is associated with inflammation or a muscular or joint problem in the lower back.

Examples include:

• Ibuprofen.

• Naproxen.

• Diclofenac.

These medications help reduce pain and inflammation, but they do not necessarily treat the underlying cause of nerve compression or damage.

Note: These medications are not suitable for everyone. They may cause stomach irritation, ulcers, or bleeding. They may also affect kidney function or increase the risk of cardiovascular problems in some people. Therefore, they should be used under medical guidance, at the lowest effective dose and for the shortest possible duration.

Second: Medications Used to Treat Neuropathic Pain

Doctors may prescribe certain medications specifically used to manage particular types of nerve pain, especially when the patient experiences burning, tingling, or electric shock-like sensations.

Medications that may be used in some cases of neuropathy include:

• Duloxetine.

• Amitriptyline.

• Pregabalin.

• Gabapentin.

These medications affect how the nervous system processes pain signals and may help relieve certain types of neuropathic pain. However, the choice of medication depends on the diagnosis and the patient's overall health. These medications also do not relieve the mechanical pressure placed on a nerve.

Important Warning: Pregabalin and gabapentin are not recommended for routine treatment of sciatica, as sufficient evidence of their effectiveness for this condition is lacking. Their use may also be associated with side effects such as dizziness and drowsiness.

Third: Muscle Relaxants

Doctors may prescribe muscle relaxants for a short period if the pain is accompanied by muscle tightness or spasms in the lower back or buttocks.

Examples include:

• Baclofen.

• Tizanidine.

• Cyclobenzaprine.

These medications help relieve certain muscle spasms, but they do not directly treat the affected nerve. They may also cause drowsiness and dizziness. Therefore, they should only be used when there is a clear medical indication and under a doctor's supervision.

Fourth: Corticosteroids (Cortisone)

Corticosteroids may be used in specific cases to reduce inflammation. The doctor determines whether they are necessary based on the underlying cause and severity of the symptoms.

They may be administered as:

• Oral tablets or medications in selected cases.

• Epidural injections near the nerve roots in some cases of pain caused by a herniated disc.

These injections may provide limited, short-term relief for some patients, but they are not suitable for every case and do not guarantee relief of nerve compression.

Note: Corticosteroids should not be used without medical supervision. They may increase blood sugar and blood pressure, affect immune function, and increase the risk of certain complications.

Fifth: Vitamins That Support Nerve Health

Doctors may recommend vitamin supplements if tests confirm a deficiency that affects nerve health. The most important include:

• Vitamin B12: Essential for maintaining nerve health and producing blood cells. A deficiency may cause numbness and sensory disturbances.

• Vitamin B1: Helps support nervous system function, and a deficiency may lead to neurological problems.

• Vitamin B6: Plays a role in nervous system function. However, taking high doses or using it for prolonged periods may cause nerve damage, resulting in numbness and tingling.

Experiencing nerve pain in the leg does not automatically mean that vitamin supplements are necessary. A deficiency should first be identified, and the appropriate dose and duration should be determined based on the doctor's assessment.

Surgical Treatment for Nerve Problems Affecting the Left Leg

Surgery is not necessary in every case of nerve inflammation or neuropathy affecting the left leg. The decision to operate depends on the underlying cause of the symptoms, the degree of nerve compression, pain severity, and whether muscle weakness or impaired movement is present.

Doctors may recommend surgery when there is significant nerve compression caused by a herniated disc or spinal canal stenosis, or when a peripheral nerve has been injured or compressed. Surgical procedures are generally divided into spinal surgeries and peripheral nerve surgeries.

First: Spinal Surgeries to Relieve Nerve Compression

These procedures are used when pain in the left leg is caused by compression of the nerve roots emerging from the lumbar vertebrae. The main procedures include:

1. Discectomy

This procedure is performed to treat certain cases of herniated discs that compress the lumbar nerve roots, causing pain that radiates from the lower back into the left leg. It may also be accompanied by numbness or muscle weakness.

How the Procedure Is Performed:

1. The patient is given anesthesia, usually general anesthesia.

2. A surgical incision is made in the lower back to access the affected vertebra.

3. The surrounding muscles and tissues are moved aside to reach the affected area.

4. The compressed nerve root is identified.

5. The protruding or herniated portion of the disc pressing on the nerve is removed, while preserving as much healthy disc tissue as possible.

6. The surgeon confirms that the nerve has been decompressed and controls any bleeding.

7. The surgical incision is closed.

Goal of the Procedure: To relieve pressure on the nerve root, reduce pain radiating into the leg, and preserve spinal stability as much as possible.

2. Microdiscectomy

Microdiscectomy is a surgical technique used to remove the herniated portion of a disc that is compressing a nerve. It is performed in some cases of sciatica caused by a herniated disc. The surgeon uses an operating microscope to obtain a magnified, detailed view of the tissues and nerves.

How the Procedure Is Performed:

1. The patient is given anesthesia, usually general anesthesia.

2. A relatively small incision is made in the lower back.

3. An operating microscope is used to visualize the disc and nerve root clearly.

4. The tissues surrounding the nerve are carefully moved aside to access the site of compression.

5. The herniated portion of the disc pressing on the nerve root is removed.

6. The surgeon confirms that the nerve has been decompressed and that no significant pressure remains.

7. The surgical incision is closed.

Advantages: This technique allows the surgeon to access the affected area with greater precision while minimizing disruption to the surrounding muscles and tissues in suitable cases. It may help relieve pain radiating into the leg.

3. Laminectomy to Decompress the Spinal Canal

This procedure is used to treat certain cases of spinal canal stenosis that cause nerve compression. The condition may lead to pain, numbness, or weakness in the legs, particularly when standing or walking.

How the Procedure Is Performed:

1. The patient is given anesthesia, usually general anesthesia.

2. A surgical incision is made in the lower back.

3. The surrounding muscles are moved aside to access the affected vertebra.

4. Part of the posterior bony arch of the vertebra, known as the lamina, is removed. Portions of thickened ligaments may also be removed when necessary.

5. The space available for the nerves is enlarged to relieve pressure on them.

6. The surgeon confirms that the nerves have been decompressed and controls any bleeding.

7. The surgical incision is closed.

Goal of the Procedure: To relieve pressure on the nerves and improve symptoms associated with spinal canal stenosis, such as pain, numbness, and difficulty walking.

4. Foraminotomy (Nerve Root Decompression)

This procedure is performed when the bony opening through which a nerve root exits between the vertebrae becomes narrowed, placing pressure on the nerve and causing pain or numbness that radiates into the left leg.

How the Procedure Is Performed:

1. The patient is given anesthesia according to the nature of the surgical procedure.

2. A surgical incision is made to access the affected vertebrae.

3. The opening through which the nerve root passes is identified.

4. Small portions of bone, ligaments, or other tissues causing compression are removed.

5. The nerve root opening is enlarged, and the surgeon confirms that the nerve is no longer compressed.

6. The surgical incision is closed.

Goal of the Procedure: To enlarge the space around the nerve root and relieve pressure on it, which may help reduce pain and numbness in the left leg.

5. Endoscopic Nerve Decompression

This procedure is used in some cases of herniated discs or foraminal stenosis. It allows the surgeon to access the affected area through a small incision using an endoscope equipped with a camera and specialized instruments.

How the Procedure Is Performed:

1. The patient is given anesthesia. The type of anesthesia is determined according to the procedure and the patient's health condition.

2. A small incision is made to insert the endoscope and surgical instruments.

3. The endoscope is guided toward the herniated disc or site of nerve compression using appropriate imaging techniques.

4. The herniated portion of the disc or the bone and tissues compressing the nerve are removed, depending on the underlying cause.

5. The surgeon confirms that the nerve has been decompressed and that pressure on it has been relieved.

6. The endoscope is removed, and the incision is closed.

Advantages: The procedure involves a relatively small incision and may reduce disruption to the surrounding muscles and tissues in suitable cases. Its suitability depends on the location and nature of the problem, as well as the surgeon's expertise.

6. Lumbar Spinal Fusion

This procedure may be used when nerve compression is accompanied by spinal instability or vertebral slippage, or when severe degenerative changes make spinal stabilization necessary.

How the Procedure Is Performed:

1. The patient is given anesthesia, usually general anesthesia.

2. The surgeon accesses the affected vertebrae through the appropriate surgical approach.

3. The damaged disc or compressive tissues are removed when necessary.

4. A bone graft or an interbody cage is placed between the vertebrae to help them fuse.

5. The vertebrae are stabilized using metal screws and rods when necessary.

6. The surgeon confirms spinal stability and closes the surgical incision.

Goal of the Procedure: To stabilize the vertebrae and reduce abnormal movement between them. It may be performed alongside nerve decompression surgery.

Important Note: Spinal fusion is not a routine treatment for sciatica or an isolated herniated disc. It is performed only when there is a clear medical indication, such as spinal instability.

Second: Peripheral Nerve Surgeries in the Left Leg

If the pain is caused by an injury to or compression of a peripheral nerve in the buttock, thigh, or leg, the patient may need specialized surgery to release or repair the nerve rather than spinal surgery.

The main procedures include:

7. Neurolysis (Surgical Release of a Nerve From Surrounding Adhesions and Scar Tissue)

This procedure is used in certain cases where a nerve is compressed by adhesions or surrounding scar tissue, which may impair its function and cause pain, numbness, or movement difficulties.

How the Procedure Is Performed:

1. The patient is given anesthesia according to the nerve's location and the nature of the procedure.

2. A surgical incision is made to access the affected nerve.

3. The surgeon identifies the adhesions or scar tissue compressing the nerve.

4. The surrounding tissues are carefully separated using specialized surgical instruments.

5. The nerve is released from the compressive tissues while preserving its integrity.

6. The surgeon confirms that the compression has been relieved and closes the incision.

In some cases, the surgeon may need to release scar tissue within the nerve sheath, a procedure known as internal neurolysis. This is determined according to the nature of the injury and the surgeon's assessment.

8. Peroneal Nerve Decompression

This procedure is performed when the common peroneal nerve is compressed near the head of the fibula, the bone located on the outer side of the knee.

Compression of this nerve may cause numbness along the outer part of the lower leg and the top of the foot, as well as difficulty lifting the foot upward, a condition known as foot drop.

How the Procedure Is Performed:

1. The patient is given anesthesia according to the individual case.

2. A surgical incision is made near the outer side of the knee.

3. The course of the peroneal nerve and the site of compression are identified.

4. The nerve is released from any surrounding ligaments or tissues compressing it.

5. The surgeon confirms that the nerve has been decompressed and that no significant pressure remains.

6. The surgical incision is closed.

Goal of the Procedure: To relieve pressure on the nerve and improve the chances of recovering sensory and motor function, depending on the severity and duration of the injury.

9. Nerve Repair Surgery

This procedure is used when a nerve has been severed due to an accident, wound, or direct injury, provided that there is a clear interruption in the nerve's continuity and its ends can be brought together and repaired without excessive tension.

How the Procedure Is Performed:

1. The patient is given anesthesia.

2. The injured portion of the nerve is exposed, and both nerve ends are identified.

3. The nerve tissue is assessed, and healthy portions are identified.

4. Damaged tissue is removed when necessary.

5. The two nerve ends are brought together and sutured using fine surgical sutures. An operating microscope may be used.

6. The surgeon ensures that there is no excessive tension at the repair site.

7. The incision is closed, and a rehabilitation program is started according to the doctor's instructions.

Goal of the Procedure: To reconnect the two ends of the nerve and allow the possibility of recovering some motor and sensory functions, depending on the nature of the injury.

10. Nerve Grafting

This procedure is used when there is a gap between the two ends of an injured nerve, making direct reconnection impossible without excessive tension.

How the Procedure Is Performed:

1. The injured portion of the nerve is exposed, and the damaged area is identified.

2. Damaged tissue is removed, and the length of the gap between the two ends is determined.

3. A suitable nerve graft is selected. It may be taken from another nerve in the patient's body or obtained from an alternative graft source, depending on the case.

4. The graft is placed between the two ends of the injured nerve.

5. The graft is connected to both ends using fine surgical sutures.

6. The surgeon ensures that the connections are secure and free from excessive tension.

7. The incision is closed, and follow-up care and rehabilitation are initiated.

Goal of the Procedure: To provide a pathway through which nerve fibers can gradually grow across the injured area, potentially helping restore some nerve functions.

11. Nerve Transfer Surgery

This procedure is used in certain severe nerve injuries when direct repair of the damaged nerve is not possible or when the chances of functional recovery are limited. It involves connecting a healthy nerve branch to another nerve or part of a nerve to restore a specific function.

How the Procedure Is Performed:

1. The injured nerve and the motor or sensory function to be restored are identified.

2. A healthy nerve branch is selected, while preserving as much of its original function as possible.

3. The selected portion of the nerve is carefully divided.

4. It is connected to the target nerve or nerve branch.

5. The connection is secured using fine surgical sutures. An operating microscope may be used.

6. The patient undergoes a rehabilitation program to retrain the muscles and improve functional recovery.

Goal of the Procedure: To provide an alternative source of nerve supply that may help restore some lost functions. Outcomes vary depending on the type, timing, and location of the injury.

12. Tendon Transfer Surgery

This procedure may be used in certain cases of severe nerve damage that result in foot drop, particularly when nerve function cannot be restored or when recovery is insufficient to improve foot movement.

How the Procedure Is Performed:

1. The patient is given anesthesia according to the nature of the procedure.

2. The surgeon identifies a suitable tendon and muscle that can compensate for the lost movement.

3. The tendon is released from its original attachment while preserving as much of the muscle's primary function as possible.

4. The tendon is transferred to a new location to help lift the foot.

5. The tendon is secured to the appropriate bone or tissue.

6. The foot is immobilized using a splint or supportive device for a period determined by the surgeon.

7. Physical therapy is gradually started once the surgeon considers it appropriate.

Goal of the Procedure: To improve the ability to lift the foot while walking and reduce tripping and falls. However, this procedure does not repair the damaged nerve itself; instead, it compensates for some of the functions of muscles that have lost their ability to move.