Cortisone injections: what they do, what they don't, and when they help

Cortisone is one of the more useful tools in sport and exercise medicine. It is also one of the most frequently misrepresented, both by people who think it cures everything and by people who think it should never be used. The truth sits somewhere more practical than either position.

What cortisone actually is

Cortisone is a corticosteroid: a synthetic version of a hormone the body produces naturally in the adrenal glands. When injected directly into a joint, bursa, or soft tissue, it acts as a potent anti-inflammatory. It is not the same as the anabolic steroids associated with performance enhancement in sport. The mechanism is entirely different and the clinical purpose is entirely different.

At this clinic, ultrasound guidance is used for corticosteroid injections where it improves accuracy. This means the needle is placed under real-time imaging, which can improve the accuracy and consistency of delivery compared with a landmark-based injection. Many patients find the procedure quicker and more comfortable than they expect, though this varies between people and procedures.

What it does well

Cortisone is most useful when the primary problem is inflammation. The conditions where it tends to be most effective include:

Bursitis (subacromial, trochanteric, olecranon, prepatellar and others)
Acute flares of osteoarthritis in a joint that has become acutely inflamed
Plantar fasciitis that has not responded to load management and physiotherapy
De Quervain's tenosynovitis (inflammation of the wrist tendon sheath)
Morton's neuroma
Certain types of shoulder pathology including calcific tendinopathy

In these situations, cortisone can reduce pain and inflammation to a point where rehabilitation becomes possible. This is the real value: not that the injection fixes the problem, but that it creates a window where the therapeutic work can happen.

What it does not do

Cortisone does not repair structural damage. If a tendon is torn, a cartilage defect exists, or a nerve is compressed by a structural problem, cortisone can reduce the inflammation around that problem but it cannot address the underlying structure. Pain reduction after an injection in these cases is temporary unless the structural issue is also managed.

For certain tendinopathies, particularly mid-portion Achilles tendinopathy, corticosteroid injection is generally not recommended. There is reasonable evidence that it can weaken the tendon tissue in this location and worsen outcomes in the medium term. This is a condition where other approaches, including load management and specific rehabilitation programmes, have a stronger evidence base.

Cortisone is also not appropriate when infection is a possibility, or in certain patients where systemic effects would be a concern. These are things a clinical assessment will determine.

How many is too many

The question of how many cortisone injections are reasonable into a single site is one that comes up regularly in clinic. The general guidance is that three injections into a single joint in a calendar year is a reasonable upper limit, and most clinical scenarios require considerably fewer than that.

Beyond a certain number, the evidence for benefit becomes thinner and the theoretical concerns about effects on cartilage and tendon tissue increase. In practice, if a joint requires repeated cortisone injections to remain comfortable, that is a signal that the injection is managing a symptom rather than contributing to a solution, and a different approach to the underlying problem is warranted.

The clinical conversation about whether to proceed with an injection, and how it fits into a broader management plan, is part of what the consultation covers. An injection is rarely the only recommendation. See the injection therapies page for more on what the clinic offers.

What to expect after an injection

A cortisone flare is a recognised phenomenon where the injected area becomes more painful for 24 to 48 hours after the procedure. It affects a minority of patients and typically resolves without treatment. Ice and simple analgesia can help during this period.

The anti-inflammatory effect generally builds over several days to two weeks. Patients often notice gradual improvement in that window rather than immediate change. If there is no improvement at two weeks, it is worth reviewing whether the diagnosis and injection target were appropriate.

Returning to full activity immediately after an injection is generally not recommended. The exact advice depends on the site and the clinical picture. This is discussed at the time of the procedure.

For a full list of injection therapies available at the clinic, including PRP, see the injection therapies page.