This is a 16 year old with a 1 year history of knee pain. The pre-op x-ray is on the left, and the immediate post op on the right with the Herbert screws. The lower photo shows the healed lesion 3 months later.
This is the arthroscopic view of the lesion seen in the xrays above. The probe indicates the soft bouncy area of the sub-chondral bone. The articular cartilage is intact. The photo on the right is after insertion of the screws.
The question is when to remove these screws.
This make one think of bioabsorbable pins. This is a case of an OCD that had been pinned 17 years ealier. The lesion has healed but the one pin may be proud and causing some problems. He has narrowing of the cartilage space on the medial side. The long standing photos show that the line of weight bearing is through the medial compartment.
The best treatment now, is to remove the pin arthroscopically, and do a valgus osteotomy.