RheumaView Insights
Osteoarthritis, the Calusa, and the oldest version of my job
South Florida is built on shells. Drive or paddle the coast below Tampa and you pass mounds of them, some enormous, piled up over centuries by the people who lived here long before the resorts. The largest belong to the Calusa, who dominated southwest Florida for roughly two thousand years and ran a whole society on fish and shellfish without farming. I spent part of a trip thinking about them, not for the shells but for the bone mixed into the same ground, and for what a bone can still say about a joint long after its owner is gone.
This is, in a sense, my own work pushed back a thousand years. I spend my days reading joints, usually on a radiograph of a living patient. But the features I look for are laid down in bone, and bone keeps them long after the soft tissue is gone. The field that reads them in the dead is paleopathology, and its core move is the same one I make on a screen: infer the history of a joint from the marks it carries.
Who the Calusa were
The Calusa lived along the estuaries and barrier islands of what are now Lee, Charlotte, and Collier counties, west and south of present-day Fort Myers. Their capital was at Mound Key, an island in Estero Bay made almost entirely of shell and clay. They were not the people of the Keys proper, a common mix-up, but of the southwest coast, and they were among the few complex societies anywhere to build that complexity on fishing rather than agriculture. Estimates put their numbers somewhere between several thousand and ten thousand at their height. They engineered canals, some cut clear across islands for canoe travel, accumulated the great shell mounds that still dot the coast, and held political sway over much of southern Florida until European disease and warfare destroyed them by the late eighteenth century.
Before going any further I want to be plain about something. The skeletal remains of Indigenous people are not specimens to be discussed casually. In the United States they are protected under federal law, and the trend in the field, correctly, is toward consultation with descendant communities and repatriation rather than display. So I am writing here about method and principle, about what bone can reveal in general and what has been documented in the broader archaeological record of the region, not about putting any particular ancestor on a table.
What osteoarthritis leaves behind
Osteoarthritis is, at its core, a mechanical disease of cartilage, and that is exactly why it leaves a durable record. Cartilage itself does not survive in the ground, but the bone underneath it does, and the bone reacts to the loss of its cushion in ways that outlast everything soft.
The most telling sign is eburnation. When cartilage wears through completely, bone grinds on bone, and the surface polishes to a dense, ivory-smooth sheen, sometimes grooved in the direction the joint moved. For a paleopathologist it is close to a definitive marker of osteoarthritis, the finding that settles the diagnosis where softer evidence is ambiguous. Around it are the same features I read on film: osteophytes, the bony lips and spurs at joint margins; porosity, a fine pitting of the surface; subchondral remodeling under load. A skeletal report and a radiology report end up using more or less the same words.
There is a second category of marking that interests me just as much, because it sits closer to the soft-tissue rheumatology I deal with: entheseal changes. An enthesis is the point where a tendon or ligament anchors into bone. Heavy, repetitive loading of a muscle can leave its attachment site roughened, built up, or pitted, and these marks have been studied since the 1980s as musculoskeletal stress markers, used to reconstruct what people habitually did with their bodies. The logic is appealing: a lifetime of paddling, hauling nets, or diving for shellfish should write itself into the shoulders and elbows.
The honest caveat
This is where the paleopathologist and the rheumatologist run into the same wall. For a long time the assumption was that more arthritis and heavier entheseal change meant a harder physical life, and that you could read someone’s occupation off their skeleton. It turned out to be messier than that. Age drives both osteoarthritis and entheseal change, often more strongly than activity does. Body size, sex, genetics, and metabolic factors all feed in. Two people who did the same work for the same years can end up with very different joints. The marks are real but multifactorial, and treating them as a simple log of labor asks more of the bone than it can give.
That is not an academic point for me; it is the caution I work with in clinic. A radiograph showing severe osteoarthritis does not tell me how much pain the patient is in, and someone in real pain may have a film that looks close to normal. Structure and experience are related but not the same, in a skeleton from Estero Bay as much as in a seventy-year-old in my office. Bone records what happened to the joint, not what it felt like to live in.
What the coast would have done to a body
Within those limits, the regional archaeology of the southeastern United States does support some careful, broad readings, and the Calusa way of life points one direction. A people who lived from the water, in canoes, working nets and lines and diving the estuaries, would have loaded the upper body hard and often. Comparative studies of prehistoric southeastern populations, and of marine foragers in general, tend to find degenerative and entheseal change clustered in the shoulders, elbows, and spine. Those are the joints a competitive rower or a commercial fisherman wears out now, for the same mechanical reasons.
The osteoarthritis I diagnose on a modern film is not a modern disease. It shows up in animals that predate humans, and in essentially every human population ever examined, including ones with none of the things we like to blame for it: no desk work, no processed food, no long old age. Mostly it is what joints do when they are used for a lifetime. The Calusa got it in shoulders worn down by paddling. My patients get it in knees, hips, and hands. It is the same process I am trying to pin down in a radiographic report.
Why this is the oldest version of RheumaView
What a paleopathologist does with a skeleton and what I am trying to systematize with imaging come down to the same act. You take a joint that cannot answer questions, describe the structural marks on it precisely, and reason backward to what happened. The terms carry over almost unchanged between a bioarchaeology monograph and a musculoskeletal radiology report. What differs is the time elapsed, and whether the patient is still around to argue with the reading.
I came to south Florida for the water and the quiet. But the shells are full of bone, the bone is full of joints, and a worn shoulder a thousand years old is still legible to anyone who knows the marks. That it can be read with the same vocabulary I use on a screen on a Tuesday afternoon is most of the reason the trip stuck with me. The Calusa fishermen are long gone. The record their joints kept is not.
Olga Goodman, MD · RheumaView Insights