Why would a knee replacement be redone in two stages, weeks apart?
Dr. Mahajan is Chairman Orthopaedics, Joint Replacement & Chief Robotic Joint Replacement at Max Smart Super Speciality Hospital, Saket.
A man with diabetes needed his knee replacement redone, and Dr Ramneek Mahajan planned it in two stages, with the patient's blood sugar brought under control first.
Which operation did the patient need?
Dr Mahajan says the patient had a revision knee replacement, an operation to redo an earlier knee replacement, done in two stages.
What made the operation harder, and how was the patient prepared?
Dr Mahajan says the patient's family was told why managing the patient's diabetes and controlling his blood sugar matter so much before a replacement. Patients with diabetes need to control their blood sugar, improve their diet and keep up with exercise.
How was the operation done in two stages?
Dr Mahajan describes the steps.
In the first stage, the diabetes was brought under control and the implant was taken out; the implant is the artificial joint put in at the first replacement. The knee was then washed thoroughly. An antibiotic spacer, a temporary block that carries medicine against infection and holds the joint's place between the two stages, was then put into the knee.
After six weeks the knee was free of infection, and there was a wait of another six weeks.
Tests before the second stage showed no infection and the sugar under control: HbA1c, a blood test that shows the average blood sugar over the past two to three months, had come down below 6, and blood sugar was around 90.
Then the second stage was done.
How did the patient recover?
Dr Mahajan says that, about a week to ten days after the operation, the patient is standing and walking, and is ready to fly home.
What should a patient with diabetes ask before a knee replacement is redone?
This is one man's story, not a promise: what an operation can do for you depends on your own case.
Ask what HbA1c and blood sugar readings your surgeon wants to see before the operation.
Ask whether the operation will be done in one stage or two, and how long the wait between them is.
What this case teaches
An antibiotic spacer stays in the knee through a course of antibiotics, often 6 weeks or longer, the American Academy of Orthopaedic Surgeons explains.
People with diabetes were about 50% more likely to have a complication after a first hip or knee replacement, a 2025 one-centre study found.
In first hip and knee replacements, complication risk rose with HbA1c, and fell sharply when a high HbA1c came back down, the same study found.
