What it is
The triceps runs down the back of the upper arm, and its three heads join into one tendon that attaches to the point of the elbow (the olecranon); it straightens the elbow. Triceps tendinopathy, often called triceps tendonitis, is a gradual ache at the back of the elbow, worse straightening it against resistance. A tear can be partial, with some of the tendon still attached, or complete.
Sources 1, 2
How rare it isEmerging evidence
Tears are rare. In US emergency departments over 20 years, triceps tendon ruptures were about 0.5% of the tendon ruptures seen, about 1 in 200, at 0.02 per 100,000 people a year, with men at 12 times the rate of women and an average age of 44. Not everyone with a tear goes to an emergency department, so this probably undercounts them. In US active-duty military personnel the rate was 1.1 per 100,000 a year, and in a region of Slovakia 0.46 per 100,000.
The tendon has a broad, strong attachment, so it tears less often than other tendons, and reviews call tears rare or exceedingly rare. Triceps tendinopathy without a tear is described as very rare, with little published about it.
Sources 3, 4, 5, 1, 6, 2
Who gets it, and whyEmerging evidence
Most tears come from pushing a heavy load, in lifting or sport, or from a fall onto an outstretched hand, often as the triceps contracts while being forced to bend. In the US National Football League, 37 tears needed repair over 10 seasons, 86% of them in linemen, who missed 165 days on average. In another series of 19 professional players, 7 had warning pain before the tear.
Some things weaken the tendon: anabolic steroids, steroid injections, kidney disease, diabetes, an overactive parathyroid gland and a bursitis at the point of the elbow. In a review of 262 operated tears, kidney disease (10%) and anabolic steroid use (7%) were the commonest conditions, and 5 of the 19 football players had had a cortisone injection. These are links, not proof that each one caused the tear.
Sources 1, 7, 8, 9, 10, 11
Fluoroquinolone antibioticsMixed evidence
The UK's Medicines and Healthcare products Regulatory Agency (MHRA) warns that fluoroquinolone antibiotics can damage tendons, especially the Achilles tendon but also others, within 48 hours of starting or months after stopping, more often over 60, with kidney problems, after an organ transplant or when taken with steroid tablets. A UK study found the link only for Achilles ruptures (about 3 times the usual rate, and about 19 times with steroid tablets too), with no link to ruptures of the biceps or other tendons. No study looked at the triceps.
Sources 12, 13, 14
How it's told apart
An examination tells these apart. These are the usual patterns.
- Triceps tendonitis: an ache at the tip of the elbow or just above it, tender on the tendon, worse with dips, close-grip presses, skull crushers and push-ups.
- A tear: sudden sharp pain and swelling at the back of the elbow, bruising down the back of the elbow and forearm, a gap you can feel above the point of the elbow, and weakness straightening the elbow, especially overhead. Weakness isn't always obvious at first, and tears are often missed while the elbow is swollen: 10 of 23 in one series.
- Olecranon bursitis: a soft swelling on the point of the elbow, often after leaning on it.
- In throwers: pain at the back of the elbow as the arm straightens can be bone spurs or a stress fracture of the elbow tip.
- A snapping triceps: a snap over the inner elbow as it bends, usually with an unstable ulnar nerve (58 of 64 reported cases), sometimes with tingling in the little finger.
Sources 1, 7, 15, 16, 17
Scans: when they helpEmerging evidence
With a suspected tear, an X-ray can show a small fleck of bone pulled off with the tendon (in 61% to 88% of operated tears in one review), and an ultrasound or magnetic resonance imaging (MRI) scan confirms the tear and how much of the tendon is involved, which guides treatment.
For tendon pain without a tear, a scan is rarely needed, and pain-free elbows often look abnormal: in 205 MRI scans every triceps tendon showed a line of bright signal, which the authors think is normal, and 9 of 26 pain-free professional baseball pitchers had changes where the triceps attaches.
Sources 1, 10, 18, 19
How it usually goes
There are no studies of how triceps tendonitis settles. In a case report, a climber's back-of-elbow pain went from 4 to 0 out of 10 over 10 weeks of shoulder-blade and triceps exercises, and she returned to her previous level. Of 10 partial tears in professional American football players, 6 healed without surgery, 1 later tore completely and 3 had repairs after the season for ongoing pain and weakness. The American Academy of Orthopaedic Surgeons (AAOS) says results without surgery are often satisfactory when less than half the tendon is torn, while bigger tears usually leave some lasting weakness.
Sources 20, 8, 1