Again noted is the circumferential solid periosteal new bone formation around the proximal tibial diaphysis. There is a focal intramedullary region of low T1, high STIR signal in the proximal third of the tibial diaphysis indicating a focal fluid collection. At this site, there is a collection of heterogenous T1/STIR signal posteriorly which most likely represents evolving late sub-acute and chronic blood and/or proteinaceous cellular debris.
A cloaca extends from this lesion through the involucrum to a draining sinus tract anteromedially.
No definitive sequestrum is identified.