Medicines and injections
What can a steroid injection achieve?
Separate short-term pain relief from the long-term management plan.
At a glance
- The main goal is short-term symptom control.
- Report diabetes, recent injections and surgery plans.
- Review benefit and adverse effects before repeating.
An injection may make the knee feel better quickly, but it is important to understand what that improvement means. A joint steroid injection treats inflammation and pain. It is not a cartilage-regrowing injection or a treatment everyone should receive repeatedly.
The role of a steroid injection
- 01
Assess
Cause of pain and swelling; glucose risk
- 02
Control
Benefit and duration vary
- 03
Review
Exercise, alternatives and need for repetition
Assessment, short-term control and reassessment
Consider a short-term role
It may be considered when other medicines are unsuitable or insufficient, or when pain relief can support exercise. First assess the reason for current pain and swelling.
NICE describes the expected benefit as generally short term, around 2–10 weeks. This is not a promise of the same duration for everyone; some people obtain little or brief relief.
Less pain does not establish joint repair
Relief can support appropriately adjusted exercise and activity. It does not prove cartilage regeneration or long-term prevention of osteoarthritis progression.
Do not suddenly increase walking or exercise because pain has eased. Record walking, sleep and swelling before and after the injection to discuss its actual benefit.
Check glucose and infection concerns
Blood glucose may rise temporarily in people with diabetes. Agree on monitoring and medicine management. Report anticoagulants, prior injection reactions, suspected infection and planned surgery.
Brief discomfort can occur after an injection, but progressively worsening pain, heat or swelling, fever or feeling unwell needs prompt medical review. Contact the treating clinic or another medical service without delay. Absence of fever does not rule out infection.
Base repetition on response and the wider plan
Review benefit, adverse effects and alternatives rather than scheduling indefinite injections by a fixed calendar. Concerns about joint tissues also matter with prolonged repeated use.
If surgery is being considered, give the surgical team the injection type and date. Reassess diagnosis and other treatment options when repeated injections provide little benefit.
Can I have a joint injection before knee replacement?
If you are planning knee replacement, tell the surgical team what was injected into that knee and when. Discuss avoiding corticosteroid or hyaluronic acid joint injections during the three months before surgery. If you have already had an injection, ask your surgeon about the timing of surgery rather than cancelling it yourself.
A 2019 study of 58,337 knee replacements found higher odds of infection around the prosthesis when an injection had been given within the preceding three months. The odds ratio was 1.21 for corticosteroid and 1.55 for hyaluronic acid. This was an observational study of insurance records. These figures do not establish causation or predict an individual patient’s infection risk.
Common Questions
Does it improve cartilage?
It may reduce pain and inflammation, but it is not described as regrowing worn cartilage.
What happens to blood glucose?
A temporary rise is possible. Plan monitoring and action beforehand if you have diabetes.
How often should I have one?
Timing depends on the treatment, response, risk and surgery plans; there is no universal repeat schedule.
Evidence and references
01When to seek medical care
Each warning sign is a separate reason to seek care. Follow the action below if any one applies.
Emergency department · call 119 in Korea
- Call 119 for sudden breathlessness or chest pain, severe faintness or loss of consciousness. Do not wait for calf swelling to appear.
- Go to an emergency department if you suddenly cannot bear any weight, or if an injured knee swells rapidly or looks deformed. A cold or numb foot after injury also needs immediate assessment.
- Seek emergency care for a hot, swollen and severely painful joint with high fever, shaking chills, confusion or inability to bear weight.
- With back or leg pain, go immediately to an emergency department for new difficulty passing urine, loss of bladder or bowel control, or numbness around the genitals or anus. Severe or rapidly worsening weakness or numbness in both legs also needs immediate assessment.
Same-day assessment
- Arrange assessment today for a newly hot, swollen joint, sudden severe pain, or a knee locked so that it cannot fully straighten. Joint infection can occur without fever.
- Have new swelling or pain in one calf assessed today for a possible blood clot. Call 119 immediately if breathlessness or chest pain develops.
- Severe knee pain or a new limp in a growing adolescent may come from a hip condition such as slipped capital femoral epiphysis. Stop walking and sport and arrange assessment today. Go directly to emergency care if they cannot bear weight.
- Stop running and seek assessment today for new recurring groin pain, pain with walking or at night, or a limp. A femoral neck stress fracture needs to be considered. Keep weight off the painful leg until assessed. Go to emergency care if you cannot bear weight.
Book an outpatient appointment
- If none of the warning signs above is present, book an appointment for pain lasting a few weeks, repeated swelling or reduced daily activity and exercise.