Case Study: Computer navigated Primary Knee replacement

A 59 year-old lady who was seen in our clinic as a new patient for her right knee. She describes having pain in her knee that has lasted almost 2 years at the point we saw her, and although she leads a relatively sedentary lifestyle, she has noticed significant increases in her levels of pain over the last 6 months. She works as a librarian in a small town, and she has noticed even getting around the library to be troublesome, especially towards the end of the day.

She had been prescribed anti-inflammatory medication by her GP which has helped somewhat, and although she had not attempted any physiotherapy, she had purchased knee braces which she wears at work every day. Although they helped initially, she doesn’t feel like they are effective any more.

Her medical history was significant for psoriasis, anxiety and previous gall bladder surgery. She has an allergy to penicillin and is an ex-smoker, having quit 2 decades ago.

Her knee examination was unremarkable, although she was visibly uncomfortable during it. Her X-rays reveal varus osteoarthritis with significant posterior disease as compared to more anteriorly.

We explained to Mrs. JN she would likely require a knee replacement to relieve her symptoms as the normal non-operative modalities have all become ineffective for her. She agreed and consented to a Total Knee Replacement. We explained to her we would be using a technique known as Navigation, with a computer helping us complete the procedure.

During her surgery, we used a special instrument designed to help the computer build a 3D picture of her knee. Once the picture is completed with enough reference points, the computer then communicates with sensors on other instruments that tell us the exact position and orientation the cutting guides need to be in for the bone cuts to be aligned accurately.

We completed her knee replacement with the aid of the computer navigation system. She recovered well and left hospital the day after her surgery.

She regained most of her knee strength within 3 months of her surgery, and is still happy with how her knee feels 2 years after her replacement was done.

Pre op

Computer-navigated primary knee replacement.

Post-op

Computer navigated primary knee-replacement.