Why does the Achilles tendon hurt?
The tendon can withstand enormous loads, but recovers poorly due to the relatively poor blood supply, especially in the area a few centimeters above the insertion site. When the volume of load increases faster than the tissue has time to rebuild, microdamage accumulates: fibers lose order, vessels and nerve endings grow into the tissue, which causes pain. The classic situation is that a person sharply increased their mileage, returned to running after a break, changed their shoes, or started training uphill. There are two locations: in the middle part of the tendon and at the point of attachment to the heel, and the treatment for them is slightly different.
- Poor blood supply to the mid tendon
- Microdamage due to overload
- Tissue remodeling instead of classic inflammation
- Shape in the middle part of the tendon
- Shape at the point of attachment to the calcaneus
Risk factors
The most common is increasing the load too quickly. To this are added technical and biomechanical features: shortened calf muscles, weakness of the lower leg and buttock muscles, excessive pronation of the foot, flat feet. Shoes with worn out soles or too hard heels, running on hard surfaces and uphill, and lack of warm-up are important. General factors deserve special attention: age after forty years, excess weight, diabetes mellitus, lipid metabolism disorders. It is especially worth remembering about taking fluoroquinolone antibiotics and glucocorticosteroids, which increase the risk of damage and rupture of the tendon.
- A sharp increase in the volume and intensity of training
- Running on hard surfaces and uphill
- Worn or ill-fitting shoes
- Shortening of the calf muscles
- Flat feet and overpronation
- Overweight
- Age after 40 years
- Diabetes mellitus and lipid metabolism disorders
- Taking fluoroquinolones and glucocorticosteroids
Symptoms
The pain is localized in the tendon area above the heel or right at the insertion site. Morning stiffness is very typical: the first steps after waking up are difficult, but then it becomes easier. At the beginning of training, the pain intensifies, when warming up it can decrease, and after exercise and the next day it returns stronger. Over time, the tendon thickens, a painful spindle-shaped compaction appears when palpated, and sometimes a slight crunch is felt when the foot moves. It is important to distinguish this condition from a rupture: with a rupture, the pain occurs suddenly, often with a sensation of a blow from behind, and the person cannot stand on his toes.
- Pain 2–6 cm above the heel or at its insertion
- Morning stiffness and pain during the first steps
- Increased pain at the beginning of exercise
- Increased pain the day after exercise
- Thickening and tenderness of the tendon
- Limitation of toe rise
Diagnostics
In most cases, the diagnosis is made during examination: the doctor evaluates pain along the tendon, its thickness, range of motion in the ankle joint and flexibility of the calf muscles. Be sure to rule out a rupture using a special test, in which compression of the calf muscle normally causes movement of the foot. Ultrasound of soft tissues shows thickening of the tendon, changes in structure, the appearance of blood vessels and the presence of fluid in the surrounding membranes; the method is accessible and allows observation in dynamics. MRI is used when the picture is unclear and before surgery. With bilateral lesions in a young person, especially in combination with back pain, inflammatory diseases of the spine should be excluded.
- Inspection and palpation of the tendon
- Calf raise assessment
- Tendon integrity test
- Ultrasound of soft tissues and ankle joint
- MRI for unclear picture
- Examination for spondyloarthritis with bilateral lesions
Treatment
A key method with proven effectiveness is eccentric exercises: slowly lowering the heel below the level of support while standing on a step, performed daily according to a certain pattern for several months. They stimulate the restructuring of tendon tissue. The load is adjusted, but complete rest is not recommended: it weakens the tendon. In the acute period, reduce running volumes, switch to swimming and cycling, and use cold after exercise. Heel pads, properly fitting shoes, and stretching of the calf muscles are helpful. For persistent pain, shock wave therapy and other physical therapy methods are added. Injections of glucocorticosteroids directly into the tendon are not used due to the risk of rupture. Surgery is rarely required.
- Eccentric exercises as the basis of treatment
- Reducing but not stopping the load
- Swimming and cycling during the recovery period
- Calf stretch
- Cold after exercise
- Heel pads and suitable shoes
- Shockwave therapy for persistent pain
- Avoidance of hormone injections into the tendon
- Gradual return to running