The Color of Life
Red is the color. So much depends on red. Healthy red blood is the essence of all tissues and even the determinant of the health of bone. I look at life through this prism and notice the shades suggestive of this injury or that disease. I read those signals to predict outcomes.
As a surgeon, I live in a world of red. My first encounter with a patient starts with a handshake, a smile, and a look into their eyes. When the hand is warm, the smile and gaze are often warm too. The chill of waiting in an exam room is quickly replaced by a dialogue, a dance of information and inquiry. And then a physical exam. If my hands are cold, I warm them first. Rubbing them together causes the blood to rush to the surface. Patients always appreciate warm hands.
The skin of patients tells me so much. Dry, scaly, cold skin is not worrisome to the orthopaedic surgeon. But hot skin, reddened by swelling, indicates an injury is being suffused with healing blood—or that an infection is brewing. Red flashes a warning when it is too bright.
The tissues on the inside of the body have their own shades of red and health. The meniscus—that key shock absorber protecting the knee from arthritis—appears mostly white, with an outer margin of blood vessels penetrating to only one-third of the tissue’s width. When torn in the outer edge, it bleeds well and heals well when sutures are applied. The inner portion requires novel techniques to bring a new blood supply to the injured tissues. When done successfully, even edge-to-edge inner tears can heal well—but only when reddened.
The surface of the ACL is swathed in a plexus of red and blue vessels. This silken coat of synovium brings nutrients to this crucial ligament, permitting the extension, flexion, and rotation of the knee joint. When ruptured during skiing, football, or soccer; the vessels burst, sometimes filling the joint with fresh blood. If left alone, this new blood forms a dark red clot around the torn tissue as it tries desperately to provide a healing scaffold for the liberated platelets and stem-cell-derived self-repair cells to migrate into. Those cells stimulate fibrocytes to lay down new collagen fibers. These new matrices, unfortunately, usually lead to scar formation rather than to a successful new ligament.
A donor ACL graft, having been washed in detergents to remove any potential contaminants, is as white as a glossy wall. In the past, we used to just lead this dead string through the knee, replacing the torn ligament. Today we preload the tissue with growth factors from platelets which jumpstart the healing process. If they are to last, these white ligaments must evolve into a reddish perfused graft surrounded by a new jacket of synovium.
The bone we encounter in joints with injured cartilage is often exposed and hardened. Though it was once covered by a smooth, white articular cartilage layer, impact injuries can knock off this cap and the pressure of load-bearing deforms the underlying bone. When we are young, our joint bones are often reddish-brown: filled with marrow and fat, stem cells and blood cells. When injured and/or aged, the color shifts to yellow. I’ll even see darker, iron-colored bone, especially at the joint surface. But a fresh supply of healthy marrow blood can often be induced to perfuse these areas and guided to restore the cartilage surface. If left alone, bone death ensues.
Red is the color of life. So much of what we do medically is to bring red to white, red to brown, red to dead, in the hopes of resurrection, repair, regeneration, and replacement. When I see red, I am happy.
