There is no single X-ray finding or pain score that determines when a hip or knee replacement is needed. The right time is a personal decision — reached when arthritis is significantly affecting your quality of life, conservative options have been genuinely tried, and you are medically ready for surgery. The decision is always made together.
Quality of Life — The Key Driver
Surgery is considered when arthritis meaningfully impacts your daily life — when pain disrupts sleep, when you can no longer do the activities that matter to you, when conservative management is no longer effective. These are deeply personal thresholds and vary from patient to patient.
X-rays guide diagnosis and severity assessment, but they do not determine when surgery is needed. A patient with severe X-ray changes may function very well; another with moderate changes may be significantly limited. Your symptoms and function are the primary drivers of any surgical decision.
Being Medically Ready
The best surgical outcomes occur when patients are as medically optimised as possible at the time of their operation. This means:
- Blood pressure controlled
- Blood sugar (HbA1c) optimised for diabetic patients
- BMI as low as practical
- Smoking ceased at least 6 weeks prior
- Any active infections (skin, dental, urinary) treated beforehand
"The right time for surgery is always a shared decision. We will get there together at your pace."
— Dr Chien-Wen Liew
Watch Dr Chien-Wen Liew discuss this topic.
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