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Hypervascular or Hypertrophic: (horse hoof)

-  Discussion:
    - hypertrophic non unions are rich in callus and have a rich blood supply in the ends of the fragments;
    - they result from insecure fixation (inadequate stability) or premature wt bearing in a reduced fracture whose fragments are viable; 
    - fracture is capable of mounting a healing response to injury
    - hypertrophic nonunion displays exuberant callus on radiographs
    - there is increased uptake on radionuclide scans;
    - management:
           - may have high incidence of union after rigid ORIF compression plates or medullary nails, and cancellous bone grafts are optional; 
           - handling of the non union site:
                  - note that fibrous scar tissue connecting the bone ends of a hypertrophic nonunion has the capacity to turn into bone;
                  - if angulatory deformity is not present, these nonunions do not have to be opened and debrided (w/ angulatory deformity open debridement
                           of the frx may be necessary because of stiffness and resistance to correction); 
                  - hence debriding the nonunion to excise the fibrous tissue between the bone ends is not required;
                  - opening the medullary canal proximally and distally may promote healing w/o taking down a firm fibrous union;
                  - references:
                          - Technique to Prepare the Bed for Autologous Bone Grafting in Nonunion Surgery
                          - Judet decortication and compression plate fixation of long bone non-union: Is bone graft necessary?
                          - Judet osteoperiosteal decortication for treatment of non-union: the Cornwall experience
           - reaming:
                   - in many cases, however, the medullary canal of the non union site will not allow nail passage and therefore reaming is required;
                   - if reaming is to be performed, then consider opening frx site and reaming under direct vision since it is possible that blind reaming will
                          result in eccentric reaming and cortical perforation; 
           - plate fixation:
                    - providing adequate fracture stability may be all that is necessary to induce fracture stability;
                    - references:
                            - Judet decortication and compression plate fixation of long bone non-union: Is bone graft necessary?
                            - Augmentation Plate Fixation for the Treatment of Femoral and Tibial Nonunion After Intramedullary Nailing
           - external fixation:
                    - references:
                            - Distraction osteogenesis in the treatment of stiff hypertrophic nonunions using the Ilizarov apparatus.
                            - Mechanical and biological treatment of long bone non-unions.