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- Discussion:
    - plays a role in intertroch stability;
    - evaluate size & displacement of lesser troch before judging instability;
    - lesser troch has a postero-medial location and when this structure is frx & displaced, defect results at post medial aspect of frx surfaces;
    - axial loading studies of Unstable frx have confirmed that posteromedial frag (PMF) is keystone to mechanical stability and attempts should be made to include this fragment w/ internal fixation;
- Radiographs:
    - medial defect promotes varus angluation
    - posterior defect promotes retroversion
    - either of these may cause bending, breaking, or cutting out of implant;
- Treatment:
    - when anatomic reduction is possible, fixation of the PMF becomes progressively more important as its size increases;
    - need to treat these fractures as unstable