Knee OA – A GP’s perspective

12th October 2018, Dr Chee L Khoo

Imagine a 55 year gentleman come in with right knee pain. He was an active football player from years gone by and suffered the usual meniscal tears here and there over the years. He is now a storeman in the local factory and takes his dog for a walk most days. Yes, he’s put on some weight over the years and he has usual mild hypertension, mild hypercholesterolaemia and maybe borderline glucose. Life goes on.

Plain x-ray of the right knee 2 years ago showed a little more than mild degenerative arthritis of the medial compartment. Not unexpected, considering the previous meniscal injuries he had. He gets the odd pain by the end of the week. Worse if he does a bit of gardening. Over the last few weeks (actually months), his right knee has been bothering him more. More painful, more swollen and stiffer. Every so often, it locks up and he limps a bit more for a few hours. He doesn’t remember injuring his knee. You would have called that a flare up of his arthritis, wouldn’t you?

You examined him. He walked with a limp, not being able to put full weight on his right knee. There was moderate effusion in the knee. He had lost full extension and full flexion was painful. There was a suggestion of postero-medial joint line tenderness. The medial condyle was slightly tender. No laxity of the cruciate ligaments but then it’s swollen and painful to examine thoroughly. But no major trauma to suspect an ACL tear really.

Clinically, it may be a medial meniscal tear. It could be a loose body giving rise to those locking episodes. Maybe, it is a flare up of the arthritis. But then why would a knee with no injury suddenly flare up. What flares up anyway? Something would have to be further injured to be responsible for the flare up. Let’s organise another plain x-ray again. What do you think it’s going to show? More of the same – mild to moderate arthritis from two years ago. Not likely to be significantly worse in two years. That is very unlikely to help us in our management anyway.

Let’s work on the clinical diagnosis of a medial meniscal tear and send him for physiotherapy and for good measure, an exercise physiologist (EP) after that. We will see him in 6 weeks. He’s back and no better. Still limping heavily. He has been taking panadeine extra (by the way, he needs more prescriptions since they are no longer available over the counter). Maybe the odd nurofen but they don’t do much and the chemist told them that they may make his hypertension worse.

We could organise an MRI of the knee. But wait, from November 2018, MRI for the knees for over 50 is not medicare rebatable! There are other changes to MRI entitlements as well. He now has more tenderness in the posterior horn area. There is still a significant effusion. ROM is still limited. You can see some quadriceps wasting already because it’s been months since he had the flare up.

Click here to see the changes from November.

We could give him a cortisone injection if all else fails. But it’s not going to be cheap as cortisone injection item number has been removed from GP. The local radiology charges >$100 for the procedure since he is not on a pension or health care card.

We could send him off to see the orthopaedic surgeon. He is definitely too young for a knee replacement. We could do an arthroscopy but wait, that’s frown upon now because studies apparently show that arthroscopy does not affect the long term outcomes of patients who have degenerative arthritis waiting to have their TKR done. So, we should not waste money on them while waiting for a TKR. What do we do then?

He doesn’t want to keep coming to get his panadeine extra prescriptions. He can’t take NSAIDs. He can’t afford ongoing physiotherapy or EP (five visits don’t last long). The surgeon can’t do anything till he is closer to 65 years old. His quadriceps are wasting away. His right knee is getting more unstable. His back is now painful because of his abnormal gait. He no longer walks the dog because he can’t.

Perhaps, the meniscal tear could be trimmed and give him some relief. Perhaps, if we could do an MRI. We may see not just the meniscal tear but also possible loose bodies. That could be a reason the orthopaedic surgeon can use to organise an arthroscopy (maybe).

I have no answers to this common clinical scenario that you and I see at the practice. This case illustrate the idiocy of cutting out those items because someone read some abstract somewhere and the bureaucrats seize on them to cut costs. This patient will gain weight and his medication list will pile up. Diabetes might be coming too. The cost of his health care will be enormous soon. Looks like we will have to refer these patients to the orthopaedic surgeon and he will probably order an MRI anyway.

His knee will be a wreck by the time he has a TKR in 8 years’ time (ok not quite 65 but close enough). This is how OA is managed in general practice. Sad.