Femoral Nerve Radiculopathy From Lower Back Injury

Introduction

Femoral nerve pain associated with lower back injury typically results from compression or irritation of the nerve roots that contribute to the femoral nerve (L2-L4). Such compression can occur due to lumbar disc injury, spinal stenosis, or other degenerative spinal conditions causing radiculopathy.

Symptoms

When the femoral nerve is affected by a lower back injury, patients may experience a combination of symptoms that include:

1. Lower Back Pain: Generalised pain in the lumbar region, often exacerbated by movement or prolonged sitting.

2. Radiating Pain: Sharp, shooting pain that travels from the lower back down the front of the thigh, potentially reaching the medial side of the leg and foot. This pain pattern follows the path of the femoral nerve.

3. Motor Deficits: Weakness in the quadriceps muscle group, leading to difficulty with knee extension. This can make tasks such as climbing stairs, rising from a seated position, or walking challenging.

4. Sensory Changes: Numbness, tingling, or a burning sensation in the anterior and medial thigh. There may also be decreased sensation in these areas.

5. Reflex Changes: Reduced or absent patellar reflex (knee-jerk) is a common sign of femoral nerve involvement.

Diagnosis

Diagnosis typically involves a thorough clinical examination, including assessment of muscle strength, sensory function, and reflexes. Imaging studies such as MRI or CT scans of the lumbar spine can identify disc herniation, spinal stenosis, or other structural abnormalities contributing to nerve compression. Electromyography (EMG) and nerve conduction studies may also be used to assess the extent of nerve damage.

Treatments

Treatment for femoral nerve pain due to a lower back injury can be conservative or surgical, depending on the severity and underlying cause.

Conservative Treatments

1. Physiotherapy:

• Exercises: Strengthening and stretching exercises targeting the lumbar spine and thigh muscles can help improve stability, reduce nerve compression, restore pain free range of motion and improve symptoms

• Manual Therapy: Techniques such as spinal mobilisation and soft tissue release can relieve pressure on the nerve roots, relieve muscle spasm, reduce pain and restore range of motion.

2. Activity Modification: Avoiding activities that exacerbate symptoms and adopting ergonomic practices can prevent further irritation.

3. Medications:

• Under the guidance of your GP, NSAIDs, Muscle Relaxants and Neuropathic Pain Medications may be prescribed to help reduce inflammation, relieve muscle spasms, and manage pain

4. Epidural Steroid Injections: Corticosteroid injections into the epidural space of the spine can reduce inflammation and provide significant pain relief.

Surgical Treatments

Surgery is considered when conservative treatments fail, or if there is significant nerve compression causing severe pain or functional impairment.

1. Discectomy: Removal of a herniated disc that is pressing on the nerve root.

2. Laminectomy: Removal of part of the vertebra to create more space for the nerves.

3. Spinal Fusion: Stabilising the spine by fusing two or more vertebrae, often used in cases of severe spinal instability.

Prognosis

The prognosis for femoral nerve pain associated with lower back injury varies. Many patients experience significant improvement with conservative treatments, although recovery can take several weeks to months. 2 year outcomes for surgical vs. non-surgical interventions in treatment of lower back pain with radiculopathy were the same (Zhang, Wang & McAlonan 2012). Early diagnosis and treatment are critical for optimal outcomes and to ensure recovery and prevent recurrence. 

If you’re experiencing these symptoms and this condition, we can help at Brisbane Physiotherapy!