Virtual Reality Treatment for Phantom Limb Pain

Patients with limb amputations experience the sensation of the missing extremity, which is sometimes coupled with a persistent and debilitating pain in the missing limb, a condition known as phantom limb pain (PLP). This study will test the use of virtual reality (VR) training as a possible treatment of PLP.

Approximately 90% of patients with limb amputations experience the persistent sensation of the missing extremity, a phenomenon known as phantom limb (PL). Most patients with PL also experience a persistent and debilitating pain in the missing limb, a condition known as phantom limb pain (PLP).PLP is often attributed to a disruption of the primary sensory-motor representation, generating "noise" in the representation of the missing extremity, manifesting as pain. If loss of sensory feedback causes degradation of the these cortices, interventions that provide visual feedback about the missing extremity might fine-tune the primary sensory-motor cortices, thereby reducing pain. Within this framework, the present study explores the use of virtual reality (VR) training as a possible treatment of PLP. Twenty-five subjects with lower-limb amputation and chronic PLP will undergo a Virtual Reality (VR) treatment (17 one-hour sessions) consisting in two phases: a Distraction VR phase (5-7 sessions) in which they will explore VR environments using a joystick and a Lower-Limb VR treatment phase (10-12 sessions) in which they will participate in a variety of games and activities using their VR lower-limbs. A comprehensive battery for the assessment of the characteristics, intensity and the daily-life implication of PLP will be presented before and after the treatment and in three follow up testing sessions (1,4, 8 weeks). Furthermore, pain intensity will be assessed before and after each VR session. A dramatic reduction of PLP is expected after the VR treatment and that these beneficial effects remain stable in time.

Lower Limb Amputation Above Knee (Injury), Lower Limb Amputation Below Knee (Injury), Phantom Limb Pain

In the first phase (A), subjects will receive the Distraction VR treatment during 5, 6, or 7 one-hour-long sessions occurring twice weekly. After the A phase, the remaining sessions (B phase) will consist of Lower-Limb VR treatment. This number includes a mean of 6 (range 5-7) phase A sessions and mean of 11 (range 10-12) phase B sessions.

The training sessions consist of Phase 1 (Distractor VR) in which patients will explore VR environments and Phase 2 (Lower limb VR) in which they will play games using their VR lower-limbs.

In the first phase (A), subjects will receive the Distraction VR treatment during 5, 6, or 7 one-hour-long sessions occurring twice weekly. After the A phase, the remaining sessions (B phase) will consist of Lower-Limb VR treatment. This number includes a mean of 6 (range 5-7) phase A sessions and mean of 11 (range 10-12) phase B sessions.

The Brief Pain Inventory is a questionnaire which provide a description of the type and location of pain (question 1-2),the pain severity (question 3-6 pain rating scales with 0-10 range - with 10 indicating severe pain), of the current treatment for pain (question 7-8) and the pain interference in daily life (question 9- range from 0 to 10 with a maximum score of 10 indicating severe interference). A decrease (i.e. reduction in the scores) in pain severity and in the pain interference in daily activity is expected as consequence of the virtual reality training.

The McGill Pain Questionnaire is a questionnaire which provide a description of the type of pain using series of adjectives on of the pain severity, using a visual analogue scale (range of 0-100 range - with 100 indicating severe pain). A decrease in pain severity (decrease in the score in the visual analogue scale) is expected as consequence of the virtual reality training.

The the Frenchay Activities Index is a 15 items questionnaire, which investigate how often people perform certain daily activity (e.g. preparing meals), using a scale from 0 to 3, with a score of 3 indicating that the activity is performed frequently. An increase in the Frenchay Activities Index is expected as consequence of the virtual reality training.

The12-Item Short Form Health Survey is a questionnaire which investigate the quality of emotional and physical heath of individuals. An improvement in the quality of the individuals' health is expected as consequence of the training.

The Hospital Anxiety and Depression Scale measures depression is a 14 questions scale, which measure the level of depression and anxiety (maximum score of 21 indicating abnormal performance). A decrease in the score in this scale is expected as consequence of the virtual reality training

The Limb Deficiency and Phantom Limb questionnaire investigate qualitatively the phantom limb sensations.A reduction in the reported phantom limb sensation is expected as consequence of the virtual reality training

The 13-item Pain Catastrophizing scale assesses the level of negative thoughts and feeling associated with pain using a scale from 0-4 (score of 4 indicating highest frequency; maximum overall score 52). A reduction of the overall score is expected after the virtual reality training

Inclusion Criteria: Subjects will have undergone amputation of one leg (either above or below the knee) at least 4 months before the enrollment in the study; Will have chronic pain in the phantom limb: Exclusion Criteria: History of stroke or traumatic brain injury; Major active psychiatric illness that may interfere with required study procedures or treatments as determined by the PI on the study, who is a behavioral neurologist; Subjects with major medical illness that would be expected to interfere with their ability to complete the study will be excluded. Subjects with implanted electronic devices.

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