The peripheral lymphatic system
reacts to penetrating microorganisms and self-antigens released from tissues and cells damaged by trauma or intracellular pathogens. The response of regional lymph nodes to tissue trauma has not been thoroughly studied. We investigated the changes in lower limb lymphatics and nodes after fractures and soft tissue injuries. This type of injury is frequently complicated by limb edema
. Posttraumatic edema
of lower limbs is characterized by long-lasting swelling of the limb, erythema, and increased skin temperature at the site of injury. This suggests that a local inflammatory process is proceeding, even though the process of bone or soft tissue healing is considered to be completed.
Twenty-one patients with closed lower limb bone fractures and soft tissues injuries were studied by means of isotope lymphography.
Dilated lymphatics of the entire limb were found in all patients, and 62% of them showed enlarged inguinal lymph nodes. Venous thrombosis was found in 24% of cases. There was no correlation between the degree of lymphatic dilatation, lymph node enlargement, and bone fracture or soft tissue injury or venous thrombosis. Surgical intervention was not an independent factor for lymph node enlargement.
This study has shown that although the fracture or injured tissues are clinically healed, local inflammatory reaction at the site of injury persists and cytokine signals are sent to the regional lymph nodes.