Case Study: Boomer
Modified Cranial Closing Wedge Osteotomy
Deformity Assessment
Boomer presented with a grade IV/IV medial patella luxation with a concurrent cranial cruciate ligament tear. Upon CT scan, the surgeon requested both a DFO and an mCCWO. This case study will only focus on the mCCWO procedure. Pre-operation measurements showed that the tibia needed to be corrected in all 3 planes (frontal, sagittal and transverse).
Before
After
Before
After
Before
After
Planned
Correction
TPA was corrected by removing a neutral wedge. mMPTA was corrected by taking out a concurrent wedge. The tibial tuberosity was rotated to be parallel to the ankle. Post-op model was created according to surgeon requirements, as shown to the left.
Reduction Guide Design
The surgeon requested a cranially-based reduction guide to allow for the placement of a single, medially-positioned bone plate. This reduction guide was designed to avoid impinging on the patella ligament.
Ostectomy Guide Design
The ostectomy guide was designed to be placed on the medial side of the tibia. In order to locate properly, the guide grabs the cranial part of the tibia along with portions of the caudal aspect. The cutting planes of the ostectomy guide were made thick enough to prevent defection during the cutting operations to ensure accurate measurements.
Completed Bone & Guide Prints
We printed two reduction guides and two osteotomy guides in biocompatible resin and one pre-op and one post-op bone model in standard non-biocompatible resin. We drilled out the holes in the guides to ensure appropriate clearance fits with the pins. The osteotomy guide fit the pre-op bone as anticipated, and the reduction guide could slide easily onto the post-op bone.
Surgical Outcome
This was a very difficult case due to the need for correction in three separate planes. The surgeon reported that the guides worked as intended and the surgery was satisfactory.