Superficial Blood Clots and DVT: The Odds Behind Hurts' Missed Game
The Eagles say Jalen Hurts' clot is superficial but showed movement on a second scan. Trial numbers show what that can mean, and what nobody outside the team knows.
The Eagles' statement calls Jalen Hurts' clot "superficial." Three sentences later it reports "movement in the small blood clot." Nobody outside the team's medical staff knows what happened between the two.
Hurts will miss Sunday's game against the Panthers, on Oct. 18, while the team decides "the appropriate course of treatment," with no timetable. A superficial clot forms in a vein close to the skin. A deep vein thrombosis, or DVT, forms in the deep veins, the ones not visible through the skin, where a piece can travel to the lungs. In one trial, superficial leg clots given a placebo instead of a blood thinner led to symptomatic DVT or a lung clot in 1.3% of patients within 47 days, yet roughly 1 in 5 patients in pooled studies already had a deep clot when the surface one was found.
The 1.3% comes from the placebo group of the CALISTO trial; the 1 in 5 is an 18.1% average from a 2016 pooled analysis. Neither can say where Hurts' clot sits, and that is the whole question.
What the Eagles' statement leaves out
The dates are the firm ground. Hurts was cleated in the Rams game on Sunday, Oct. 4, and asked for treatment on his calf on Thursday, Oct. 8. The ultrasound came on Saturday, Oct. 10, "out of an abundance of caution," after the flight to London and a walkthrough. It "revealed a superficial blood clot," six days after the injury.
Team doctors and doctors in London "concluded that activity and mobility were important and that Jalen could safely play." He played on Sunday, Oct. 11, in the 19-17 loss to the Jaguars. The follow-up scan, on Wednesday night, Oct. 14, came three days after the game; the statement says London doctors recommended one "within 72 hours of the game and the return flight."
Post by @Eagles
Read all of it and the gaps are plain. No vein, no size in centimeters, no location for the clot; "calf" appears only for the cleat injury and the treatment. It does not say whether the deep veins were scanned, what treatment is under consideration, or when Hurts might return. AP and ESPN write, in their own voices, that the clot is in the calf. That is their description, not the team's.
"Movement" has no public definition. Read plainly, it is a question the second scan answers: is the clot growing, shifting or settling? Dr. Dinesh Dhanaraj, an orthopedic surgeon who told PhillyVoice he is not a vascular surgeon, said that if the clot is "getting bigger or moving," you start worrying about the deep veins. The team has not said which, if any, applies.
Hurts has offered little. On Wednesday, Oct. 14, he called it "a very unique experience, to say the least." In London he stayed out of the tunnel until just before the coin toss, and ESPN reported he rode a stationary bike between series, and that Hurts indicated this and his late entry to the field were related to the calf. NFL Network's Ian Rapoport said on the Pat McAfee Show that he would describe Hurts as "out indefinitely"; the Eagles have not said that. As of Friday morning, Oct. 16, the Eagles had released no further update. Tanner McKee, 26, is expected to start.
The odds, in absolute numbers
A clot in a surface vein usually shows up as a tender, red, warm, hardened vein under the skin; Cleveland Clinic calls it "typically a less dangerous condition than DVT." Deep-vein clots are dangerous, the clinic says, "because they can travel to the lungs and stop blood flow (pulmonary embolism)." The two systems connect. World Thrombosis Day says a superficial clot "can become more serious if they are able to enter deep veins through the perforator veins." The Merck Manual flags the saphenofemoral junction, where a surface vein in the upper leg joins the deep system, as the spot to worry about.
So how often does that happen? Two numbers belong side by side. Among 1,500 people in CALISTO's placebo group, 1.3% developed a DVT or lung clot within 47 days. Yet across 21 pooled studies, 18.1% of patients already had a DVT when the superficial clot was diagnosed. The danger is not only what a surface clot might become. Sometimes the deep clot is already there.
| Study | People | What was counted | Result |
|---|---|---|---|
| CALISTO (NEJM, 2010), placebo group | 1,500 people with leg superficial clots, no blood thinner | DVT or lung clot within 47 days | 1.3% (fondaparinux group: 0.2%) |
| CALISTO, placebo group | same | Combined outcome (death, lung clot, DVT, spread to the junction, or recurrence) | 5.9% (with fondaparinux: 0.9%) |
| POST (Annals, 2010) | 600 people followed three months, 90.5% on blood thinners | Lung clots / DVTs | 3 lung clots, 15 DVTs |
| POST | 844 people at diagnosis | Already had a DVT or symptomatic lung clot | 24.9% |
| Pooled analysis (J Thromb Haemost, 2016) | 4,358 people, 21 studies | Already had a DVT at diagnosis | 18.1% |
Three studies measure different things, so the rows are not directly comparable.
What does the 85% mean? CALISTO, funded by GlaxoSmithKline, gave 3,002 adults a daily injected blood thinner, fondaparinux, or a placebo for 45 days. The combined outcome fell by a relative 85%, which in absolute terms is 5.9% down to 0.9%, five percentage points. The trial's own line: "A total of 88 patients would need to be treated to prevent one instance of pulmonary embolism or deep-vein thrombosis." Worked out from the 1.3%, the placebo-group risk is about 1 in 77 over 47 days.
The POST study, of 844 French patients with clots at least 5 cm long, found 24.9% already had a DVT or symptomatic lung clot. Of 600 followed for three months, 3 had a pulmonary embolism and 15 a DVT, though 90.5% received anticoagulants. A placebo trial, a specialist cohort and a pooled review: do not add or average them. The participants were average adults, not athletes of Hurts' age: CALISTO's averaged 57, POST's median age was 65, and Hurts is 28. POST ended early because of slow recruitment.
How a clot's size and position decide treatment
This is what the second scan feeds. A Glasgow health-board guideline has most suspected superficial clots get a compression ultrasound, and the choice turns on length and distance from the saphenofemoral junction. A small clot far from the deep system gets warm compresses, elevation, anti-inflammatory drugs, compression stockings and time; Cleveland Clinic says these typically resolve within a few weeks. A clot of 5 cm or more, more than 3 cm from the junction, gets about 45 days of a blood thinner (roughly six and a half weeks). Within 3 cm of the junction, Merck says to treat it like a DVT for six weeks or longer. A true DVT means blood thinners for "at least 3 months," the NHS says.
A doctor also weighs the patient's history: a clotting condition or earlier DVT, in Cleveland Clinic's list. This is a rule set, not a forecast. Hurts' clot size and position are unknown, so he cannot be placed on it.
Why do these clots form at all? Injury to the vein is one named trigger. Cleveland Clinic also lists long sitting as a trigger; the NHS adds journeys of more than four hours and dehydration. The London trip fits that picture, but no one has shown it caused anything: Dr. Alina Mitina, an emergency physician, wrote to Sports Illustrated's Eagles site that "we can't definitively say the flight to London worsened his condition," though she called flying after a leg injury "a high-risk environment." The pooled review cuts the other way too, since recent trauma and younger age went with lower odds of a deep clot being present.
Outside doctors, labeled as guesses
None is reported to have examined Hurts, and the team has confirmed none of it. Dr. Erik Wolters of Tower Health told WFMZ: "In his case, it's superficial. It's downstream of the knee, so there's no concern for a [deep vein thrombosis]." The team never said the clot is below the knee. Dr. Brian Sutterer, on X, started from the other end: "if this has progressed to a deep vein clot instead of lower risk superficial he could be looking at the end of his season." One asserts the premise; the other conditions on it. The statement supports neither.
Dr. Christopher Yi, a vascular surgeon, read the team's silence this way: "They probably need to monitor him for longer or they may be putting him on blood thinners." He added you "can't go back to playing football on blood thinners," which is a doctor's view of the rule, not NFL policy. The sharpest line is Dr. Tom Christ's: "Right now with the limited intel released there's no way to project the rest of his season and time missed."
When a leg clot needs care today
A tender, red, warm, hardened vein in your own leg needs a scan promptly. Ultrasound confirms the diagnosis and checks the deep veins, which, given the pooled numbers, is not a formality. Do not treat yourself with a blood thinner, and do not wait it out.
Throbbing pain in one leg, usually in the calf or thigh, with swelling and red, blue or darkened skin, may be a DVT. The NHS says to seek an urgent appointment, with a hospital ultrasound within 24 hours. Add shortness of breath or chest pain and it becomes an emergency: call 911 in the U.S. or 999 in the U.K. For anyone just back from a long trip, prevention is dull and useful: stand and walk, stay hydrated, and if blood thinners are started, the NHS says to delay flights until at least two weeks after. This is general information, not medical advice.
As of Friday, Oct. 16, the Eagles have promised a treatment decision and no date for it. Sunday's kickoff against the Panthers is two days away.
