This single-institution retrospective study evaluates 247 GMRS rotating-hinge knee megaprostheses implanted for bone tumors at the distal femur and proximal tibia between 2003 and 2010. It asks whether implant survivorship, failure mode distribution, and functional outcomes differ by anatomic site and by primary versus revision reconstruction.
When counseling a patient facing limb salvage with a knee megaprosthesis, you need real numbers — and this paper provides the largest single-institution dataset for the modern GMRS rotating-hinge system.
Infection is the failure mode that will most likely end the implant's life, not mechanical breakage. With a rotating-hinge design, structural failure is essentially zero. Budget for an infection rate around 9-11% in primary cases, and counsel patients accordingly.
The proximal tibia looks scarier on raw numbers (36.7% total failure rate), but survival curves are statistically equivalent to the distal femur. Aggressive soft tissue coverage with a gastrocnemius flap in every proximal tibial case is the practice this paper validates.
When a patient presents with a failed prior reconstruction (allograft, older prosthesis, or composite), converting to a GMRS revision megaprosthesis achieves significantly better survival than a primary implant in a virgin field (80% vs. 60% at 5 years). This counterintuitive finding should inform your expectations: the revision setting is not automatically worse.
This single-institution retrospective study evaluates 247 GMRS rotating-hinge knee megaprostheses implanted for bone tumors at the distal femur and proximal tibia between 2003 and 2010. It asks whether implant survivorship, failure mode distribution, and functional outcomes differ by anatomic site and by primary versus revision reconstruction.
When counseling a patient facing limb salvage with a knee megaprosthesis, you need real numbers — and this paper provides the largest single-institution dataset for the modern GMRS rotating-hinge system.
Infection is the failure mode that will most likely end the implant's life, not mechanical breakage. With a rotating-hinge design, structural failure is essentially zero. Budget for an infection rate around 9-11% in primary cases, and counsel patients accordingly.
The proximal tibia looks scarier on raw numbers (36.7% total failure rate), but survival curves are statistically equivalent to the distal femur. Aggressive soft tissue coverage with a gastrocnemius flap in every proximal tibial case is the practice this paper validates.
When a patient presents with a failed prior reconstruction (allograft, older prosthesis, or composite), converting to a GMRS revision megaprosthesis achieves significantly better survival than a primary implant in a virgin field (80% vs. 60% at 5 years). This counterintuitive finding should inform your expectations: the revision setting is not automatically worse.