Influence of post-amputation pain syndrome on blood circulation in the bone residual limb

Abstract

Background. The percentage of unsatisfactory amputation results is still high. The healing of the bone remnant, the main supporting element of the residual limb, is of particular importance. The purpose was to study the effect of post-amputation pain syndrome on the nature of blood circulation in the bone residual limb. ­Materials and methods. Three series of experiments with amputation of the thigh were conducted on 54 rabbits. In the series 1 and 2, a perineural catheter was brought to the stump of the sciatic nerve. In series 1, for 20 days, ­every day for 20 minutes, mechanical irritation of the nerve was done, causing a pain syndrome using the perineural catheter. In series 2, 0.3 ml of 1% lidocaine was injected twice daily for 20 days; series 3 was a control. The follow-up periods were 1, 3, and 6 months. The study method was histological with the infusion of vessels with an ink-gelatin mixture. Results. Animals of the first series developed avascularity of the end of the stump and bone marrow, poor vascularity and absence of cellular composition in the Haversian canals, dystrophic changes in adipose bone marrow, rarefication, spongiosis, resorption, and bone fractures. In series 2, the avascularity passed quickly and by three months, the angioarchitectonics was stabilized. Revascularization of the bone stump occurs due to the preserved sources of blood circulation (intramedullary vascular network, periosteum and surrounding soft tissues) anastomosing vessels and extravascular pathways of microcirculation (increased vascular permeabi­lity, formation of sinusoidal capillaries and tissue cysts). In most observations of series 3, the processes of revascularization were similar to the results of the 1st series. Conclusions. Postamputation pain syndrome causes abrupt macro- and microcirculatory disturbances. Pain syndrome suppression allows to considerably level the arising circulatory disorders in the bone residual limb.