A Bloody Shin, Homeostasis and Automaticity

On Saturday morning, while working out in my gym and attempting to complete a series of twenty jumps on to a 24-inch box, I momentarily took my eyes off the target, stumbled, and hit my shin on the jagged edge of the box. I almost fell to the left, recovered, and completed my workout. A few minutes later, after catching my breath and downing a bottle of water, I looked down to see that a 2-inch long, bleeding gash had magically appeared; the force of the blow had pulled a small skin fold away from the open wound; it lay on the right, forming a hairy, matted, bloody, sweaty mess on my leg.  It smarted a bit, and given the potential for the intermingling of various bacterial life-forms, dirt, and the body fluids of those who had previously used the box,  it was probably best to administer a little first-aid, so after washing the wound, I walked over to our handy medical kit, swabbed the area with alcohol, applied an antiseptic cream, laid on a cotton gauze patch, taped it over, and went home.

Two days on, as I gleefully look forward to the prospect of an interesting scar (always good for a story or two), and wait for a scab to form so that the healing process can accelerate, and I can dispense with the nuisance of bandaging, I’m struck again by how injuries and the homeostatic process of healing that follows their disruption of the steady-state equilibrium of the inner and outer layers of skin, provide salutary reminders about the exquisite biochemistry of the body, about consciousness, physical sensations, and attention, and the curious mixture of automaticity and autonomy that seemingly constitutes our bodies and our selves.

I barely felt the blow that caused that wound; at that moment, a host of other sensations–my legs burned from the effort required to explosively jump up on the box–crowded out that momentary trauma caused by the impact on the splintered, sharp edge, and forced my conscious attention elsewhere. The bleeding came to a halt soon enough as platelets and fibrin-containing clots set to work to repair damaged blood vessels; and voila, the always-magical process of wound healing began.

And as that series of complex maneuvers kick off, the admixture that we are is brought front and center: I do not issue conscious directives for this healing to begin, it has ‘a mind of its own.’ I can intervene (my first aid attempts for instance), disrupt and aggravate (by exposing the wound to more trauma) or facilitate (by changing bandage dressings), but the commencement of this exercise was not under my control. Equilibria disturbed; normal service is sought to be resumed. Stand back and marvel; one is given a glimpse of the humming factory that runs 24/7 just beneath, and even on top of, our skins.

Sometimes you can pay attention to the way you sweat on a hot day; and sometimes you need a smack upside the head–or a scrape on the shin, to remind you of the finely pitched control maintained by this fantastically intricate bag of skin, bones, and blood, striving constantly to maintain its integrity against all that presses in on it from the ‘outside.’