Phantom Limb Pain.Care & specialists in New Zealand

• •Pre-amputation pain in the limb — predicts severity of post-amputation phantom pain in cohort studies
• •Insufficient perioperative analgesia, including failure to use regional anesthesia where appropriate
• •Early-onset phantom pain in the first 24-72 hours after surgery (predicts chronic phantom pain at 2 years)
• •Concurrent depression, anxiety, or post-traumatic stress symptoms in the perioperative period
• •Slow or limited engagement with prosthetic fitting and rehabilitation

Phantom limb pain is a clinical diagnosis based on the history of amputation and a characteristic post-amputation pain pattern referred to the missing body part. There is no specific imaging or laboratory test. The diagnostic workup focuses on distinguishing phantom limb pain from residual limb pain (common but treatable causes include neuroma, prosthesis fit, heterotopic ossification, infection, ischemia), characterizing severity and impact, identifying modifiable contributing factors, and screening for psychological comorbidities. History captures onset, character, frequency, duration, triggers, position of the phantom, and prior treatments. The Brief Pain Inventory, Numeric Rating Scale, painDETECT (for neuropathic features), and amputation-specific instruments such as the Trinity Amputation and Prosthesis Experience Scales (TAPES) measure interference and prosthetic use. Examination evaluates the residual limb for surgical site healing, suture line, neuroma (Tinel sign at residual nerve ending), heterotopic ossification, vascular status, and prosthetic fit. Imaging is reserved for suspected residual limb pathology: ultrasound or MRI for neuroma localization, plain radiograph for heterotopic ossification, and Doppler studies for vascular compromise. Psychological screening with PHQ-9, GAD-7, and PCL-5 is standard given the high comorbidity. Multidisciplinary assessment in an amputee or pain clinic produces an integrated treatment plan combining pain medicine, prosthetics, physical therapy, and behavioral health.

• ✓Gabapentin (900-3600 mg/day divided) or pregabalin (150-600 mg/day divided)
• ✓Tricyclic antidepressants (amitriptyline, nortriptyline, desipramine 10-100 mg at bedtime)
• ✓SNRIs (duloxetine 60-120 mg, venlafaxine XR 75-225 mg)
• ✓Topical lidocaine 5% patch

Peripheral nerve injury and neuroma formation

When a nerve is cut during amputation, the proximal end attempts to regenerate but the absent target produces a disorganized neuroma. Neuromas develop hyperexcitability, generating spontaneous discharges and amplified responses to mechanical and chemical stimuli. They contribute to both residual limb pain and central reorganization that underlies phantom pain. Targeted muscle reinnervation surgery prevents neuroma formation by giving the cut nerve a new target.

Cortical reorganization in primary somatosensory cortex

After amputation, the cortical region representing the missing limb is invaded by representations of adjacent body parts. The face cortex expands into the deafferented hand cortex following arm amputation. The degree of remapping correlates with phantom pain intensity on fMRI. Mirror therapy and graded motor imagery aim to normalize this reorganization.

Dorsal root ganglion and spinal cord sensitization

Peripheral injury increases excitability of dorsal root ganglion neurons supplying the limb and produces central sensitization in spinal cord dorsal horn. NMDA receptor activation, glial activation, and altered inhibitory transmission underpin chronic neuropathic pain components.

Pre-amputation pain memory

Pain present in the limb before amputation often persists as a similar-quality pain after surgery, as if the central nervous system has 'memorized' the pre-amputation pain state. Effective preoperative pain control reduces this risk.

Inadequate perioperative pain management

Several systematic reviews suggest that regional anesthesia (epidural in lower-limb, peripheral nerve catheter in upper-limb amputation) and multimodal analgesia for at least 48-72 hours perioperatively reduce phantom pain incidence at 6 months. Findings vary across trials but the principle is incorporated into modern guidelines.

Psychological factors (catastrophizing, depression, PTSD)

Pain catastrophizing, depression, and post-traumatic stress disorder are independent risk factors for severe and persistent phantom limb pain. They modulate central pain processing and behavioral response. Integrated mental health care reduces phantom pain interference.

Severe pre-amputation pain in the limbmodifiable

Patients with high pre-amputation pain levels have 2-3x higher rates of chronic phantom limb pain. Pre-amputation regional anesthesia and aggressive pain management may reduce this risk.

Upper-limb amputationnon-modifiable

Phantom limb pain is more common after upper-limb (75-85%) than lower-limb (60-80%) amputation, possibly because of the larger and more elaborate cortical representation of the hand and arm.

Bilateral amputation or proximal amputationnon-modifiable

Bilateral amputees and patients with proximal amputations (above-knee, above-elbow) have higher and more persistent phantom pain rates than distal amputees.

Age at amputationnon-modifiable

Amputation before age 2 produces phantom pain in 10-20% of cases; after age 8 the rate matches adult risk. Age over 50 at amputation may also increase persistent pain risk through dysvascular comorbidities.

Diabetes mellitus and peripheral vascular diseasemodifiable

Diabetes accounts for 54% of US amputations and predisposes to peripheral neuropathy, which itself increases neuropathic pain risk independent of the amputation.

Depression, anxiety, and PTSDmodifiable

• •Mediterranean-style eating pattern, associated with lower inflammatory markers and modest benefits across chronic pain conditions
• •Adequate protein intake (1-1.2 g/kg) to support residual limb wound healing and muscle conditioning
• •Vitamin D and calcium-rich foods for bone health, especially important in lower-limb amputees with reduced weight-bearing
• •For diabetic amputees, follow individualized medical nutrition therapy to maintain glycemic control

• •Excess alcohol — worsens sleep, interacts with neuropathic pain medications, and amplifies depression
• •Tobacco — impairs wound healing, accelerates vascular disease in the contralateral limb, and worsens pain perception
• •Excess caffeine that disrupts sleep when phantom pain already affects rest
• •High-glycemic-load diet in diabetic patients, which worsens neuropathy and limb-loss risk in the contralateral limb