Distal biceps tendon ruptures occur when lifting an object which exceeds your ability, causing the elbow to extend in the process. Sometimes there’s a “pop”. Pain need not be excessive.
During elbow flexion and supination (palm up) rotating the wrist against resistance, pain is felt generally. Migration of the biceps muscle towards the shoulder may be seen. Alternatively, partial tears and complete tears with an intact lacertus fibrosis will not demonstrate this deformity of the upper arm.
Partial tears can be managed expectantly, but are often recalcitrant.
In active individuals, digital repair is considered to optimize supination and flexion strength, as well as endurance. A single mini-incision and modern fixation techniques usually promote rapid rehabilitation and return to form and function.