Posttraumatic TKA Can Have Bad Outcomes

An individual may feel that his (or her) osteoarthritic knee was in about as bad a shape as a knee could be before surgery. But a study has found that a posttraumatic total knee arthroplasty (TKA) has worse outcomes than does an osteoarthritis total knee arthroplasty.

Doctors at the Mayo Clinic, Rochester, Minnesota, performed a retrospective review based on the clinic’s total joint database. They identified 23, 609 patients who had had a TKA between 1990 and 2012. Of these, 531 had a history of distal femur or proximal tibia fractures. Within this group, 341 had experienced a tibia fracture and 190 had had a femur fracture.

The researchers followed the experience of the patients until they either died or the prosthesis failed. The mean was a period of six years. The mean age of the posttraumatic group was 62 years, 60% of the subjects were female and 52% of them were obese. Fifty-six of the patients in the fracture group underwent revision surgery during the course of the study. Reasons for the surgery were infection, instability, loosening of the implant, and periprosthetic fracture.

The revision-free survival rate was significantly worse for the fracture patients than it was for those with osteoarthritis. The risk of revision in the posttraumatic group went up among patients 60 years old or younger as well as among patients who developed an infection, a hematoma, or deep venous thrombosis following their TKA.

Matthew Houdek, M.D., who presented the study results at the American Academy of Orthopaedic Surgeons (AAOS) annual convention, noted that obese or morbidly obese patients were at an increased risk for a post operative infection. Other risk factors included a history of fracture, malunion or nonunion, development of a post-operative hematoma or delayed wound healing following a TKA.

Houdek urged that patients planning to undergo TKA for post traumatic arthritis “should be counseled about the complications and complexities that may arise after surgery.”