Lymphatics of the upper body

The lymphatic drainage of the upper limb is by a superficial intermeshing network of vessels just below the skin, and by deep lymphatic channels below the deep fascia. The larger lymph vessels contain numerous valves which allow lymph to move only in a proximal direction. Both groups of vessels drain proximally and end by passing through some of the 25 to 30 lymph nodes in the axilla. This mass of lymph nodes serves to filter the lymph contained in the system and acts as an important defence mechanism in preventing the spread of infection.

The axillary lymph nodes are distributed in the axillary fat throughout the axilla but can be divided into five groups, four of which lie below pectoralis minor and one(the apical group) above pectoralis major. Ultimately, all lymph from the upper limb passes through the apical group of nodes, from where the efferent lymph channels condense to form the subclavian trunk. On the left hand side, the subclavian trunk joins the thoracic duct, while on the right it drains into the subclavian vein directly or via the right lymphatic duct.

The superficial nodes and lymph vessels

The superficial lymph vessels are found in the skin and drain lymph from the superficial tissues. In the hand a fine meshwork of vessels exists, which drain into progressively larger channels as they pass up the arm. The only superficial lymph vessels which have any consistent course are the larger ones which follow the major superficial veins. These end by passing into the axilla.

In the cubital fossa one or two lymph nodes lie medial to the basilic vein, receiving lymph from the medial fingers and ulnar half of the hand and forearm. These are also one or two lymph nodes in the infraclavicular fossa associated with the cephalic vein. These receive vessels from the shoulder and breast. A single node may be found in the deltopectoral groove.

The deep nodes and lymph vessels

The deep lymph vessels of the upper limb are less numerous than the superficial vessels with which they have many connections. Lying below the deep fascia, they accompany the major arteries in the arm. Most pass directly to the lateral group of axillary nodes. Small nodes may occur along both the radial and ulnar arteries and deep within the cubital fossa. Efferents from all of these nodes lie alongside the axillary vein, and from the pectoral and subscapular nodes pass along the lateral thoracic and subscapular arteries respectively. A central group of nodes is formed above the floor of the axilla. Although all the group receives lymph from all areas, the main drainage of the limb is to the lateral group. Drainage of the breast and anterior chest wall is to the pectoral nodes, that of the scapular region and upper back is to the subscapular nodes. Efferents from these groups pass to the central and then the apical group of nodes, the latter also receiving efferents from the superficial infraclavicular nodes.

Application

The fact that the larger lymph vessels contain valves is important during massage techniques aimed at reducing oedema. The massage strokes are applied from distal to proximal, ending at the axilla, with sufficient depth to compress the lymph vessels and encourage drainage.

Active muscle contraction will also cause compression of the lymph vessels and encourage drainage proximally. This effect can be further enhanced by placing an elastic compressive support or bandage on the upper limb and encouraging active rhythmical contraction of the arm muscles. Elevation of the arm above the level of the axilla will allow gravity to assist the lymphatic drainage.

Pneumatic splints which apply a rhythmically alternating compressive force to the arm, using a small electric compressor pump, can also achieve the effect of increasing lymphatic flow proximally, utilizing the same principles as massage.