Reorganization of motor and somatosensory cortex in upper extremity amputees with phantom limb pain.
Phantom limb pain (PLP) in amputees is associated with reorganizational changes in the somatosensory system. To investigate the relationship between somatosensory and motor reorganization and phantom limb pain, we used focal transcranial magnetic stimulation (TMS) of the motor cortex and neuroelectric source imaging of the somatosensory cortex (SI) in patients with and without phantom limb pain. For transcranial magnetic stimulation, recordings were made bilaterally from the biceps brachii, zygomaticus, and depressor labii inferioris muscles. Neuroelectric source imaging of the EEG was obtained after somatosensory stimulation of the skin overlying face and hand. Patients with phantom limb pain had larger motor-evoked potentials from the biceps brachii, and the map of outputs was larger for muscles on the amputated side compared with the intact side. The optimal scalp positions for stimulation of the zygomaticus and depressor labii inferioris muscles were displaced significantly more medially (toward the missing hand representation) in patients with phantom limb pain only. Neuroelectric source imaging revealed a similar medial displacement of the dipole center for face stimulation in patients with phantom limb pain. There was a high correlation between the magnitude of the shift of the cortical representation of the mouth into the hand area in motor and somatosensory cortex and phantom limb pain. These results show enhanced plasticity in both the motor and somatosensory domains in amputees with phantom limb pain. (+info)
Phantom movements and pain. An fMRI study in upper limb amputees.
Using functional MRI, we investigated 14 upper limb amputees and seven healthy controls during the execution of hand and lip movements and imagined movements of the phantom limb or left hand. Only patients with phantom limb pain showed a shift of the lip representation into the deafferented primary motor and somatosensory hand areas during lip movements. Displacement of the lip representation in the primary motor and somatosensory cortex was positively correlated to the amount of phantom limb pain. Thalamic activation was only present during executed movements in the healthy controls. The cerebellum showed no evidence of reorganizational changes. In amputees, movement of the intact hand showed a level of activation similar to movement of the right dominant hand in the healthy controls. During imagination of moving the phantom hand, all patients showed significantly higher activation in the contralateral primary motor and somatosensory cortices compared with imagination of hand movements in the controls. In the patients with phantom limb pain but not the pain-free amputees, imagined movement of the phantom hand activated the neighbouring face area. These data suggest selective coactivation of the cortical hand and mouth areas in patients with phantom limb pain. This reorganizational change may be the neural correlate of phantom limb pain. (+info)
Problems with excessive residual lower leg length in pediatric amputees.
We studied six pediatric amputees with long below-knee residual limbs, in order to delineate their functional and prosthetic situations, specifically in relation to problems with fitting for dynamic-response prosthetic feet. Three patients had congenital pseudoarthrosis of the tibia secondary to neurofibromatosis, one had fibular hemimelia, one had a traumatic amputation, and one had amputation secondary to burns. Five patients had Syme's amputations, one had a Boyd amputation. Ages at amputation ranged from nine months to five years (average age 3 years 1 month). After amputation, the long residual below-knee limbs allowed fitting with only the lowest-profile prostheses, such as deflection plates. In three patients, the femoral dome to tibial plafond length was greater on the amputated side than on the normal side. To allow room for more dynamic-response (and larger) foot prostheses, two patients have undergone proximal and distal tibial-fibular epiphyseodeses (one at age 5 years 10 months, the other at 3 years 7 months) and one had a proximal tibial-fibular epiphyseodesis at age 7 years 10 months. (All three patients are still skeletally immature.) The families of two other patients are considering epiphyseodeses, and one patient is not a candidate (skeletally mature). Scanogram data indicate that at skeletal maturity the epiphyseodesed patients will have adequate length distal to their residual limbs to fit larger and more dynamic-response prosthetic feet. (+info)
Patient information on phantom limb pain: a focus group study of patient experiences, perceptions and opinions.
Educating patients about their condition is regarded as a fundamental step in pain management. This study used focus groups with patients to explore their experiences and perceptions of the information on phantom pain that they received before and after amputation, and their views on improving this information. Thirty-one patients with a lower limb amputation attended one of seven focus groups. The majority reported phantom pain although there were individual variations in character, severity and persistence. There were wide variations in what people were told from occasional reports of good information to instances of people reporting little or no information from professionals. There were strong feelings that information should be given before or soon after amputation with a preference for verbal one-to-one explanations. Professionals, particularly nurses and surgeons, were regarded as the best source of information, although peer support was seen to be important. These findings indicate that people require timely up-to-date information on phantom pain which sensitively addresses the variability of the experience and provides the foundation for ongoing pain management. We propose that the information process could be improved by ensuring that professionals use standard information for patients derived from purposefully written sections in national guidelines. (+info)
Limb salvage and amputation in survivors of pediatric lower-extremity bone tumors: what are the long-term implications?
The past four decades have seen tremendous progress in the treatment of pediatric and adolescent cancers. As a consequence, there are increasing numbers of adult childhood cancer survivors. This has prompted investigation into the long-term consequences of cancer treatments. One group that merits special study is the survivors of lower-extremity bone tumors. Their function and quality of life may depend in part on both the surgery and the age at which it was performed. Comparisons between studies are difficult because small numbers of patients and the use of varying research designs and methods have limited research in this area. The purpose of this article is to review the major surgical approaches to lower-limb bone tumors and their impact on pediatric patients. The results show that survival is equivalent between amputation and limb salvage. Complications occur more frequently in limb salvage. The long-term outcomes of those undergoing amputation and limb salvage have not been found to be substantially different in regard to quality of life. In conclusion, prospective long-term follow-up of pediatric patients with lower-limb tumors is needed to (1) determine in a uniform manner the long-term complications, quality of life, and functionality of this population and describe differences within this patient population based on age at diagnosis and surgical procedure, (2) identify areas of concern that are amenable to intervention, and (3) provide clinicians and future patients a better understanding of the surgical options. (+info)
Size and blood flow of central and peripheral arteries in highly trained able-bodied and disabled athletes.
In a cross-sectional study, central and peripheral arteries were investigated noninvasively in high-performance athletes and in untrained subjects. The diastolic inner vessel diameter (D) of the thoracic and abdominal aorta, the subclavian artery (Sub), and common femoral artery (Fem) were determined by duplex sonography in 18 able-bodied professional tennis players, 34 able-bodied elite road cyclist athletes, 26 athletes with paraplegia, 17 below-knee amputated athletes, and 30 able-bodied, untrained subjects. The vessel cross-sectional areas (CSA) were set in relation to body surface area (BSA), and the cross-section index (CS-index = CSA/BSA) was calculated. Volumetric blood flow was determined in Sub and Fem via a pulsed-wave Doppler system and was set in relation to heart rate to calculate the stroke flow. A significantly increased D of Sub was found in the racket arm of able-bodied tennis players compared with the opposite arm (19%). Fem of able-bodied road cyclist athletes and of the intact limb in below-knee amputated athletes showed similar increases. D of Fem was lower in athletes with paraplegia (37%) and in below-knee amputated athletes proximal to the lesion (21%) compared with able-bodied, untrained subjects; CS-indexes were reduced 57 and 31%, respectively. Athletes with paraplegia demonstrated a larger D (19%) and a larger CS-index in Sub (54%) than able-bodied, untrained subjects. No significant differences in D and CS-indexes of the thoracic and abdominal aorta were found between any of the groups. The changes measured in Sub and Fem were associated with corresponding alterations in blood flow and stroke flow in all groups. The study suggests that the size and blood flow volume of the proximal limb arteries are adjusted to the metabolic needs of the corresponding extremity musculature and underscore the impact of exercise training or disuse on the structure and the function of the arterial system. (+info)
Education, employment, insurance, and marital status among 694 survivors of pediatric lower extremity bone tumors: a report from the childhood cancer survivor study.
BACKGROUND: With increasing numbers of childhood cancer survivors, direct sequelae of cancer therapy and psychosocial outcomes are becoming more important. The authors described psychosocial outcomes (education, employment, health insurance, and marriage) for survivors of pediatric lower extremity bone tumors. METHODS: The long-term follow-up study of the Childhood Cancer Survivor Study is a multiinstitutional cohort study comprising 14,054 individuals who have survived for 5 or more years after treatment for cancer diagnosed during childhood or adolescence. Baseline demographic and medical information were obtained. Six hundred ninety-four survivors had osteosarcoma or Ewing sarcoma of the lower extremity or pelvis and were classified by amputation status and by age at diagnosis. The median age at diagnosis was 14 years old with a median of 16 years of follow up since diagnosis. Demographic characteristics were used to analyze the rates of psychosocial outcomes. RESULTS: Amputation status and age at diagnosis did not significantly influence any of the measured psychosocial outcomes. Education was a significant positive predictor of employment, having health insurance, and being currently in their first marriage. Male gender predicted ever being employed and female gender predicted having health insurance and marriage. When compared with siblings, amputees had significant deficits in education, employment, and health insurance. CONCLUSIONS: Overall, no differences between amputees and nonamputees were found. However, gender and education play a prominent role. When compared with siblings, amputees in this cohort may benefit from additional supports. (+info)
Left and right hand recognition in upper limb amputees.
Previous research suggests a close similarity in brain activity between mental simulation of a movement and its real counterpart. To explore this similarity, we aimed to assess whether imagery is affected by the loss of a limb or of its motor skills. We examined the performance of 16 adult, upper limb amputees (and age-matched controls) in a left/right hand judgement task that implicitly requires motor imagery. The experimental group included subjects who had suffered the amputation of the dominant or the non-dominant limb. Although responding well above chance, amputees as a group were slower and less accurate than controls. Nevertheless, their response pattern was similar to that of controls, namely slower response times and more errors for stimuli depicting hands in unnatural orientations, i.e. postures difficult to reach with a real movement. Interestingly, for all stimuli, amputees' performance was strongly affected by the side of limb loss: subjects who underwent amputation of their preferred limb made more errors and required greater latencies to respond as compared with amputees of the non-dominant limb. In a further analysis we observed that the habit of wearing an aesthetic prosthesis significantly interfered with the ability to judge the corresponding hand. Our data lead to three main conclusions: (i) loss of a single limb per se does not prevent motor imagery but it significantly enhances its difficulty; (ii) these subjects apparently perform the hand recognition task using a strategy in which they initially mentally simulate movements of their dominant limb; (iii) wearing a prosthesis, devoid of any motor function, seems to interfere with motor imagery, consistent with the view that only 'tools' can be incorporated in a dynamic body schema. (+info)