Radial Nerve Paralysis in Dogs: Causes, Treatment, and Recovery

If your dog suddenly cannot extend their front leg, is dragging their paw, or walking on the top of their foot, they may be suffering from radial nerve paralysis. This condition affects the largest nerve in your dog's front leg and can be frightening to witness. The good news is that many dogs recover with proper treatment, and even those with permanent nerve damage can regain mobility through orthotic support or, in some cases, live happy lives after amputation and prosthetic fitting.

As a Certified Prosthetist-Orthotist (CPO) with over a decade of experience creating orthotic and prosthetic devices for human patients—including strength-limited veterans recovering from nerve injuries—I bring that same clinical expertise to helping pets. I understand how overwhelming this diagnosis can feel. In this comprehensive guide, I will walk you through everything you need to know about radial nerve paralysis in dogs, including the different types of nerve injuries, what recovery looks like, and how custom orthotic devices can help your dog regain function during the healing process.

What Is the Radial Nerve and Why Does It Matter?

The radial nerve is the largest nerve in your dog's front leg. It originates from the brachial plexus, which is a network of nerves in the shoulder area that receives input from spinal roots C6 through T2. According to neuroanatomical studies, the C8 spinal root contributes approximately 45 percent of the nerve fibers, making it the dominant contributor to radial nerve function.

This nerve has two critical jobs. First, it controls motor function, meaning it tells the muscles of the elbow, wrist, and toes when to extend. Second, it provides sensory function, allowing your dog to feel sensations on the front surface of the forearm and the top of the paw.

The radial nerve travels along the inside of the upper arm bone (humerus), then wraps around the outside through a groove called the musculospiral or spiral groove. This anatomical path is exactly why the radial nerve is so vulnerable to injury. When the humerus fractures, particularly in the middle or lower third, the nerve is frequently damaged.

When the radial nerve is injured, your dog loses the ability to extend the elbow, wrist, and digits. This results in the characteristic presentation of radial nerve paralysis: the leg hangs in a flexed position, the paw knuckles over, and your dog cannot bear weight on the affected limb.

Common Causes of Radial Nerve Injury

Understanding what caused your dog's nerve injury helps your veterinarian predict recovery and plan appropriate treatment. The most common causes include:

Trauma is the leading cause. Motor vehicle accidents, falls from height, bite wounds, and other traumatic injuries can directly damage the nerve or cause fractures that injure it secondarily.

Humeral fractures deserve special attention because of the nerve's path through the spiral groove of the humerus. Mid-shaft and distal third fractures frequently injure the radial nerve.

Brachial plexus avulsion occurs when severe force pulls the front leg away from the body, tearing nerve roots from the spinal cord. This often happens when a dog is hit by a car and the leg is forcibly abducted.

Tumors, particularly nerve sheath tumors like schwannomas and neurofibrosarcomas, can compress or invade the nerve. These tumors most commonly arise from the brachial plexus in dogs.

Iatrogenic causes are injuries that occur during medical procedures. Prolonged positioning during surgery can compress the radial nerve against the operating table, particularly in large, muscular dogs on inadequately padded surfaces. Tourniquet application above the elbow can also cause damage.

Your veterinarian will work to identify the underlying cause, as this significantly impacts prognosis and treatment planning.

Recognizing the Signs of Radial Nerve Paralysis

The clinical signs of radial nerve paralysis are distinctive and typically appear immediately after injury. What you observe depends on where along the nerve the damage occurred.

Signs of proximal (upper) radial nerve injury include:

• Dropped elbow with inability to extend the elbow joint
• Complete inability to extend the wrist and digits
• The paw knuckles over, with the dog walking on the top of the foot
• Inability to bear weight on the affected leg
• Dragging of the front paw when attempting to walk
• Loss of sensation on the top of the paw and front of the forearm

Signs of distal (lower) radial nerve injury include:

• Elbow extension is preserved because the triceps muscle still functions
• Paw knuckling from paralysis of wrist and toe extensors
• The dog may be able to bear some weight but the paw collapses

Additional signs that may indicate severe injury:

• Horner's syndrome (droopy eyelid, small pupil, sunken eye, elevated third eyelid) appears in approximately 50 percent of complete brachial plexus injuries
• Loss of the panniculus reflex, where the skin along the trunk normally twitches when touched
• Signs of pain or discomfort, which research shows affects approximately 73 percent of dogs with brachial plexus injuries

If you notice any of these signs, contact your veterinarian immediately. Early diagnosis and treatment improve outcomes.

The Three Types of Nerve Injury: Understanding Your Dog's Prognosis

Not all nerve injuries are equal. The Seddon classification system divides nerve injuries into three categories, and understanding which type your dog has is essential for predicting recovery.

Neuropraxia is the mildest form of nerve injury. The nerve is temporarily stunned but not structurally damaged. Think of it like a bruise to the nerve. All the internal structures remain intact, and the nerve simply cannot conduct signals temporarily due to localized swelling or mild trauma.

Dogs with neuropraxia have an excellent prognosis. Complete recovery typically occurs within days to three weeks. Your veterinarian may recommend rest, anti-inflammatory medications, and supportive care during this time.

Axonotmesis is a more serious injury where the nerve fiber itself (the axon) is disrupted, but the surrounding protective tubes (endoneurium) remain intact. Wallerian degeneration occurs, meaning the portion of the nerve beyond the injury site breaks down. However, because the protective tubes are intact, they provide a pathway for the nerve to regrow.

Nerves regenerate at approximately one to three millimeters per day, or roughly one inch per month. This means recovery from axonotmesis takes one to six months, depending on how far the nerve must regrow to reach its target muscles. The prognosis is guarded to fair, with research suggesting approximately 50 percent of dogs achieve functional recovery.

Neurotmesis is complete nerve transection where every structure, including the axon and all surrounding tissues, is severed. Scar tissue forms at the injury site, blocking regeneration. Without surgical intervention, recovery is extremely unlikely.

Unfortunately, distinguishing between axonotmesis and neurotmesis immediately after injury is impossible. Both appear identical on initial examination. Only time and repeated evaluations can differentiate them. This is why your veterinarian will recommend serial examinations over weeks to months.

How Your Veterinarian Diagnoses Radial Nerve Paralysis

Your veterinarian will perform a thorough neurological examination to diagnose radial nerve paralysis and assess its severity. The diagnostic process typically includes:

Neurological examination evaluates reflexes, muscle tone, and sensation. Your veterinarian will test proprioception by flipping the paw over and seeing if your dog corrects its position. They will also check for deep pain perception, which is an important prognostic indicator.

Electromyography (EMG) is the gold standard diagnostic tool for nerve injuries. It detects abnormal electrical activity in muscles that indicates nerve damage. EMG changes typically appear five to ten days after injury. The optimal time for comprehensive evaluation is two to four weeks post-injury.

Motor nerve conduction studies measure how well the nerve transmits signals. Research from the largest study on traumatic brachial plexus injury found that radial nerve signal amplitude was the strongest predictor of outcome. Dogs with a signal amplitude of 5 millivolts or greater had significantly better chances of recovery.

Advanced imaging such as MRI may be recommended to visualize the nerve, identify tumors, or assess for root avulsion. CT scans can identify bony involvement.

If your dog shows no clinical or electrophysiological improvement by eight weeks, your veterinarian may recommend surgical exploration to directly assess the nerve.

Treatment Options for Radial Nerve Paralysis

Treatment for radial nerve paralysis depends on the type and severity of injury, the underlying cause, and your dog's overall health. Your veterinarian will develop a comprehensive treatment plan that may include multiple approaches.

Conservative Medical Management

Most dogs with radial nerve paralysis begin with conservative treatment while waiting to see if the nerve recovers.

Anti-inflammatory medications such as NSAIDs reduce swelling around the nerve and manage pain. Common options include meloxicam and carprofen.

Neuropathic pain management with gabapentin addresses the abnormal sensations that can cause significant discomfort. Research shows pain affects the majority of dogs with brachial plexus injuries.

Vitamin B complex supplementation has been used in some treatment protocols to support nerve health, though evidence is limited.

Physical Rehabilitation

Physical therapy is crucial for maintaining joint mobility and muscle mass while waiting for nerve recovery.

Passive range of motion exercises involve gently moving the affected joints through their full range multiple times daily. This prevents contracture, which is permanent shortening of muscles and tendons from disuse.

Massage therapy maintains blood flow to affected muscles and can provide comfort.

Hydrotherapy, including swimming and underwater treadmill exercise, allows your dog to maintain muscle mass without full weight-bearing stress on the affected limb.

Neuromuscular electrical stimulation (NMES) artificially contracts muscles to prevent atrophy while voluntary movement is absent. This is particularly valuable for dogs with complete paralysis.

Laser therapy is an emerging modality that may support nerve regeneration, though clinical evidence in veterinary medicine is still developing.

Your veterinarian may refer you to a certified canine rehabilitation therapist for these services.

Orthotic Support and Custom Bracing

Custom orthotic devices play an important role in managing radial nerve paralysis, both during the recovery period and for dogs with permanent partial paralysis.

How carpal orthoses help: A custom carpal brace holds the wrist and digits in extension, preventing the paw from knuckling over. This allows your dog to bear weight on the limb, protects the paw from abrasion injuries caused by dragging, and prevents the development of contractures.

When bracing is appropriate:

• During nerve recovery from neuropraxia or axonotmesis to protect the limb across the observation period
• To prevent secondary injuries from paw dragging
• To prevent muscle contracture during recovery
• For permanent partial paralysis where some function remains
• As a complement to physical therapy

Custom versus off-the-shelf devices: As a CPO, I strongly recommend custom-molded orthotics for radial nerve patients. Custom devices are fabricated from a cast or scan of your dog's specific anatomy, ensuring proper fit and function. They use medical-grade thermoplastics and precisely placed hinges that match your dog's actual joint axis. Off-the-shelf devices come in generic sizes that may not accommodate the extreme anatomical variation between breeds.

Contraindications for bracing: Bracing may not be appropriate if there is active skin breakdown or infection at potential brace contact areas, severe swelling, or if your dog is actively self-mutilating the limb.

If your veterinarian believes your dog may benefit from orthotic support, schedule a consultation with our team to discuss options.

Surgical Options

Surgery may be considered when conservative treatment fails or when specific conditions exist.

Nerve repair (neurorrhaphy) may be attempted for clean transections if performed early.

Tendon transfer surgery is a salvage procedure where functional tendons are relocated to restore some limb function when nerve recovery does not occur.

Carpal arthrodesis fuses the wrist joint in a functional position and may be combined with tendon transfer.

Your veterinarian or a veterinary surgeon will discuss whether any surgical options are appropriate for your dog's specific situation.

What to Expect During Recovery

Recovery from radial nerve paralysis varies dramatically based on the type and severity of injury.

Neuropraxia recovery: Expect improvement within days to three weeks. Full recovery is typical.

Axonotmesis recovery: The main period of nerve regrowth occurs during the first three months. Because nerves regenerate at approximately one inch per month, the distance from the injury site to the target muscles determines how long recovery takes. If no improvement is seen by four to six weeks, the prognosis for spontaneous recovery becomes poor.

Signs that recovery is occurring:

• Return of deep pain perception is the earliest encouraging sign
• Twitching in the extensor muscles
• Reduced knuckling
• Voluntary extension of the wrist and digits
• Return of muscle bulk

Monitoring progress: Your veterinarian will recommend serial examinations, typically every two to four weeks, to track recovery. EMG studies may be repeated to assess nerve regeneration.

The largest study on traumatic brachial plexus injury followed 226 dogs and cats and found that among non-amputated dogs, 40 percent recovered motor function within three months. Recovery level remained stable through twelve-month follow-up, meaning if significant improvement has not occurred by three months, it likely will not occur.

When Amputation Becomes Necessary

For some dogs with radial nerve paralysis, amputation of the affected limb may be the best option. I know this is difficult to hear, but it is important to discuss openly.

Amputation may be recommended when:

• Self-mutilation of the insensate limb occurs, which happens because the strange sensations during attempted nerve regeneration drive some dogs to chew or bite the affected leg
• Chronic non-healing wounds develop from persistent paw dragging
• No functional recovery occurs after three to six months of treatment
• Complete nerve root avulsion is confirmed, as no treatment can repair nerves torn from the spinal cord
• Persistent neuropathic pain impairs quality of life despite medical management

Research on amputation rates: One study of 30 dogs with brachial plexus injury found that 50 percent underwent amputation, 30 percent showed no recovery but were not amputated, and only 20 percent recovered motor function. Dogs without deep pain perception had a nine times higher likelihood of amputation.

Life after amputation: Most dogs adapt remarkably well to life as a tripod. For many dogs, amputation provides better quality of life than chronic management of a painful, non-functional limb. Some dogs may be candidates for custom prosthetic limbs after amputation, which can help with balance and mobility.

If your veterinarian discusses amputation, please know this recommendation comes from a place of wanting the best quality of life for your dog.

Working With Your Veterinary Team

Managing radial nerve paralysis requires a team approach. Your veterinarian is the expert and primary decision maker for your dog's care. They may involve veterinary neurologists, surgeons, and rehabilitation specialists.

At SoCal Pet Brace, we work alongside your veterinary team to provide custom orthotic solutions when bracing is part of the treatment plan. We never recommend devices without veterinary guidance, and we communicate directly with your vet to ensure the orthotic supports your dog's overall treatment goals.

If you have questions about whether your dog might benefit from orthotic support during recovery from radial nerve paralysis, talk to your veterinarian first. If they believe a custom device could help, contact our team for a consultation. We serve pet owners throughout Southern California, including Los Angeles, Orange County, San Diego, and the Inland Empire.

Frequently Asked Questions

Can a dog recover from radial nerve paralysis?

Recovery depends on the type of nerve injury. Dogs with neuropraxia typically recover fully within weeks. Dogs with axonotmesis have approximately a 50 percent chance of functional recovery over one to six months. Dogs with neurotmesis rarely recover without surgical intervention.

How long does radial nerve paralysis take to heal?

Neuropraxia heals in days to three weeks. Axonotmesis requires one to six months because nerves regrow at approximately one inch per month. If no improvement occurs by six to eight weeks, the prognosis becomes poor.

Is radial nerve paralysis painful for dogs?

Research shows approximately 73 percent of dogs with brachial plexus injuries experience signs of pain or discomfort. Your veterinarian can prescribe medications like gabapentin to manage neuropathic pain.

What is the difference between neuropraxia, axonotmesis, and neurotmesis?

Neuropraxia is temporary nerve stunning with excellent prognosis. Axonotmesis involves damage to the nerve fiber but intact surrounding tissue, allowing regrowth with guarded prognosis. Neurotmesis is complete nerve transection with poor prognosis for spontaneous recovery.

Can a brace help a dog with radial nerve paralysis?

Yes, custom orthotic devices can support dogs with radial nerve paralysis by holding the paw in proper position, preventing knuckling and paw dragging, and protecting against secondary injuries during the recovery period.

When should a dog's leg be amputated after nerve damage?

Amputation may be considered if no recovery occurs after three to six months, if the dog is self-mutilating the limb, if chronic wounds develop, or if persistent pain impairs quality of life. Your veterinarian will help you make this decision.