Developing an in-depth understanding of the prevalence, risk factors and treatment recommendations for phantom limb pain, and patient-generated care priorities for people who have undergone lower limb amputations

Introduction: Phantom limb pain is a common complication in people who have undergone limb amputation, with prevalence estimates ranging between 29% and 85.6%. Current systematic-review evidence suggests that recommended treatments are no more effective than placebo for reducing Phantom Limb Pain (PLP). Moreover, there is evidence suggesting that people with amputations may not be getting the treatment they want at different time-points after amputation. In consideration of these points, a research project comprised of a series of interconnected studies aimed to develop an in-depth understanding of the global burden of PLP and patient care priorities after limb amputations, and generate expert recommendations on the best management of PLP in people with amputations. Methods: The research project is comprised of a series of four interconnected studies addressing the four primary aims of the project. A systematic review and meta-analysis were conducted to determine the pooled prevalence estimate and risk factors for PLP in people with amputations. A cross sectional study was conducted to determine the prevalence and risk factors for PLP in people who had undergone lower limb amputations at Groote Schuur Hospital. An expert Delphi study was conducted to reach expert consensus and make recommendations on the effective treatments for PLP in people with limb amputations. Lastly, a patient Delphi study was conducted to generate patient consensus on care priorities for people who have had lower limb amputation for a year or less and for those who have had lower limb amputations for more than a year. Results: The systematic review and meta-analysis of 39 studies revealed a pooled PLP prevalence estimate of 64% [95%CI: 60.01 – 68.05], with a significantly higher prevalence estimate in studies conducted in developed countries 66.55% [95% CI: 62.02 –71.64] than those conducted in developing countries 53.98% [95% CI: 44.79–63.05] (U = 57, p = 0.03). Risk factors that were consistently positively associated with PLP included having an amputation of a lower limb, stump pain, non-painful phantom sensations, persistent pre-amputation pain, proximal site of amputation, and diabetic cause of amputation. The cross-sectional study using a sample of African people with amputations showed a PLP prevalence of 50.78% [95% CI: 41.80 – 59.72] during the week preceding data collection. In this group of patients, persistent pre-operative pain was the only risk factor associated with PLP in the multivariate logistic regression analysis [OR 2.25 (1.03 – 5.05); P=0.04]. In the expert Delphi study, consensus was reached on one pharmacological (amitriptyline) and six nonpharmacological (Graded Motor Imagery, mirror therapy, Cognitive Behavioural Therapy, virtual reality training, sensory discrimination training, use of a functional prosthesis) treatments that were considered effective for managing PLP, and on two treatments [citalopram (60%) and Pulsed Radiofrequency Stimulation of the dorsal root ganglion (70%)] that were considered ineffective. In the patient Delphi study, consensus was reached on 24 short-term care priorities and 12 long-term care priorities. The general consensus among the participants was that pre-amputation, they wanted education support to help them manage their expectations and prepare for life after amputation. In the early stage after amputation, they wanted help with dealing with the psychological trauma of having lost a limb. In the long-term, however, the participants prioritised the need for living a functional and normal life, with respect and dignity like everyone else. Conclusion: The prevalence of PLP in people with limb amputations is high, and awareness of this condition needs to be raised among healthcare professionals to implement evidence-based strategies for alleviating PLP by targeting the relevant underlying mechanisms and modifiable risk factors. Evidence-based medicine indicates that PLP is best managed using non-pharmacological and noninterventional treatments addressing biopsychosocial contributors for PLP. Finally, preparing people for life after amputation and helping them deal with the psychological trauma of having lost a limb may contribute to improved clinical outcomes that may enable them to live a functional and normal life, with respect and dignity