"COMMUNICATING LYMPHATICS" AND LYMPHO-VENOUS COMMUNICATIONS IN RELATION TO DEEP VENOUS OCCLUSION OF THE LEG

Abstract

Dilatation (ectasia) of the subcutaneous lymphatics and opening up of new lymphatic channels were observed in cases of swollen legs due to deep venous thrombosis of the calf- (Fig. 1) (9, 1, 7). The severer the degree of deep venous occlusion, the more the subcutaneous lymphatics were found to dilate and the more channels to open-up, denoting a direct relationship between the flow of lymph in the subcutaneous lymphatics and the increased venous tension within the musculo-fascial compartment of the leg (3). This points to the existence of some form of mechanism whereby the effects of such an intrafascial deep venous hypertension could be transmitted to the subcutaneous lymphatics across the tough deep fascia of the leg. The following suggestions were put forward for the explanation of such a mechanism:
1. In deep venous hypertension of the calf, the high pressure in the deep veins is "blown-out" into the subcutaneous veins (5). With an increased pressure in the subcutaneous veins, a decreased uptake of normal capillary effusion with an increased tissue pressure would result in the formation of excessive amounts of tissue fluids which, in turn, throws an increased load on the subcutaneous lymphatics.
2. The possible existence in the leg of lymph vessels, which cross the deep fascia, similar to communicating veins. These may help to drain tissue fluids from within the deep fascia outwards into the subcutaneous lymphatics.
3. The possible existence in the leg of functioning lympho-venous communications which could transmit the increased venous tension directly to the subcutaneous lymphatic trunks.

This article embodies a histological and an anatomical search for lymph vessels which traverse the fascia cruris and for lympho-venous communications, as well as an attempt at the assessment of the direction of flow of lymph in the deep and subcutaneous tissues of the human leg.