The Hip: Preservation, Replacement and Revision

Universal Large Distractor


- Discussion:
    - length & alignment are restored by use of femoral distractor in saggital plane, w/o need for fracture table;
    - this permits hip and knee to be flexed on the table during nailing;
    - the distractor may be particularly suited to poly trauma patients;
    - disadvantage is that image intensification control is difficult to obtain in the lateral view;

- Proximal Schanz Screw:
    - note that the proximal position of the pin must allow meduallary reaming and subsequent nailing to be carried out w/o interference;
    - horizontal approach:
          - 5 mm half pin is placed laterally into the lesser trochanter, w/ the half pin directed slightly upward (20 deg) from a posterior to anterior direction;
          - pin is directed 90 deg to long axis of femur;
    - vertical approach:
          - proximal screw will pierce the rectus femoris muscle and often will also pierce the lateral edge of the sartorius;
          - the femoral nerve, artery, and vein all lie medial to the screw;
                 - the femoral nerve is closest to the pin, lying 2.5 cm medial;
          - the half pin should be inserted only after the nail is driven into the proximal fragment;
                 - the target is the proximal femur, just medial (and sl distal to) the lesser trochanter;

- Distal Schanz Screw:
    - inserted just proximal to the condylar area in the anterior 1/3 of the femur;
    - distally the Schanz screw must be removed before final nail insertion;
    - pin is directed 90 deg to long axis of femur;

- Femoral Shaft Frx:
    - pressure on the proximal fragment is exerted by the assistant to over-come tendency to extend w/ knee flexion;
    - some manual support of frx is usually needed to control angulation;
    - once the two Schanz screws are in place, the distractor is attached securely, and is threaded length adjustment is used to apply traction across the fracture site;
    - typically mild apex anterior angulation of the fracture is controlled with manual pressure during reduction and nail insertion;
    - alternatively, some surgeons will apply traction to the distractor only in cases in which the reduction cannot be accomplished w/ manual traction alone


Technique of Using the AO Femoral Distractor for Femoral IM Nailing

Intramedullary Nailing of Acute Femoral Shaft Fractures Without a Fracture Table: Technique of Using a Femoral Distractor.



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

Last updated by Data Trace Staff on Friday, August 3, 2012 9:04 am