PreOp Planning for Removal of Cemented Stems

- Evaluate Proximal Stem:
    - decide whether trochanteric osteotomy is required;
    - it is essential to avoid a proximal femoral frx while extracting the stem;
    - direct extraction of a femoral stem can be blocked by excessive cement or proximal bony overgrowth medial to the greater trochanter;
    - this situation is worsened if the femoral stem is curved;
    - surgical options are to remove the impedeing bone or cement which overly the lateral aspect of the stem (using high speed burr or osteotomes) or
          to perform a trochanteric osteotomy;
    - in either case, the lateral aspect of the stem shold be visualized prior to stem removal;

- Evaluate Distal Stem:
     - note areas cement fragmentation;
     - note on lateral view, where the femur begins to curve anteriorly;
     - this will indicate how far distally cement chisels may pass;
     - note amount of distal cement plugging;
     - in the past 2 cm of distal plugging was recommended, often because the stems were end bearing;
     - w/ more than 1-2 cm of cement, the procedure becomes much more complex;

- Surgical Instruments:

- Visualization:
     - arthroscopic lamp;
     - windowing of the femur;
          - trochanteric osteotomy:
          - offers more complete access to proximal femur but comprimises stability provided greater trochanter to press fit system;
          - flouroscopy:
               - image intensification is extremely useful in avoiding bone damage, but it introduces increased risks of potential contamination of the surgical site

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, September 7, 2011 4:25 pm