Craniodorsal hip luxation is a common problem in dogs. For various reasons, open reduction techniques are often employed to restore hip integrity and function. The Knowles toggle pin technique is a popular method of achieving stability because it
- Allows immediate limited weight-bearing
- Does not require greater trochanteric osteotomy
- Requires minimal instrumentation to perform
This technique begins by resecting the remnants of the round ligament and drilling a hole through the ligament's origin in the acetabular fossa, just ventral to the articular surface. Protecting the surrounding tissues (femoral head, acetabulum, and associated soft tissues) is important to preventing iatrogenic injury to those structures during drilling of the hole.
While drill guides are commercially available, a less expensive option is to use a tuberculin syringe barrel for an impromptu, DIY drill sleeve.
- Cut the tip off a tuberculin syringe barrel (where the needle attaches) using a scalpel blade to open the full barrel diameter
- Hold the remaining portion in your nondominant hand or, alternatively, with an Allis or similar forcep
- Place the enlarged syringe tip against the acetabular fossa in the desired location to begin predrilling your hole
Drill bits as large as 4.5mm will fit through the syringe barrel. The guide can also be re-used by sterilizing it with steam, ethylene oxide, or plasma sterilization methods.
Tip submitted by Mark Rochat, DVM, MS, DACVS - Oklahoma State University, Stillwater, OK