Is mirror therapy associated with progressive muscle relaxation more effective than mirror therapy alone in reducing phantom limb pain in patients with lower limb amputation?

Mirror therapy is a widely used treatment for phantom limb pain (PLP) relief in patients with limb loss. Less common is progressive muscle relaxation (PMR), used mostly in other medical conditions (psychological, terminal cancer pain, etc). The purpose of this study is to evaluate the efficacy of a mirror therapy preceded by PMR intervention compared to mirror therapy preceded by unguided generic relaxation-mirror therapy in patients with lower limb amputation suffering from PLP. This pilot study was a single-blind, controlled, randomized trial. Thirty lower limb amputees suffering from PLP were recruited and randomly assigned to three groups respectively undergoing a PMR-mirror therapy rehabilitative intervention, generic relaxation-mirror therapy, and conventional physiotherapy (ConvPT). Selected items from Prosthesis Evaluation Questionnaire (PEQ) and the Brief Pain Inventory (BPI) were used to test the pain features at the beginning and 1 week after 3 weeks of intervention. A decrease of about 65% was found in the rate and duration of PLP at the PEQ in PMR-mirror therapy with respect to generic relaxation-mirror therapy (about 30%) and ConvPT (about 6%). A decrease of about 90% in intensity (worst and average) of PLP in PMR-mirror therapy when compared to generic relaxation-mirror therapy (about 45%) and ConvPT (about 20%) was found at the BPI. We preliminary concluded, albeit with limitations due to the small sample of patients, that mirror therapy can improve PLP when associated with PMR. Further studies are required to confirm that PMR could be an effective technique for more successful PLP management.