Week 5

This week I continued to see patients and observe surgeries with Dr. Bostrom. I was able to see some fairly complex revision surgeries. One patient had practically every complication that typically makes you a poor candidate for surgery in addition to the reasons she was getting a revision. She had already had two revisions, multiple back surgeries, PE, DVT, diabetes, heterotopic ossification, and a stress reaction at the distal end of the femoral stem of the implant. They placed a bone strut next to the femur to add support around the stress reaction to prevent it from developing into a fracture. Another patient was undergoing a total hip replacement, but already had a plate near the acetabulum. When the acetabulum was being reamed, flakes of metal from the plate were coming out with the bone. The acetabular component that was used was held in place by screws, which then had to be carefully placed so they avoided the metal plate but were still anchored in bone.

There were some interesting knee revisions as well. For one of them, the plan was to leave the femoral component alone and just switch out the spacer. However, once the knee was opened up they found that the femoral component was visibly loose and needed to be replaced as well. Along with the loosening, there was a lot of bone loss beneath the implant, so the new femoral component had an extra spacer underneath the medial side to compensate.

I have also been doing a lot of reading for my research project to learn more about how PTH influences bone formation. I have been looking into how mechanical loading changes formation in conjunction with PTH treatment, and whether different types of loading can affect the PTH related changes.