Can Surgeons Predict What Makes a Good TKA?: Intraoperative Surgeon Impression of TKA Quality Does Not Correlate With Knee Society Scores

Background Surgeons generally agree on what they want to achieve when performing TKA. However, we do not know which technical quality goals are correct, important, or irrelevant to achieve adequate function or durability.

Questions/purposes We asked whether a surgeon can predict postoperative Knee Society scores (KSSs) of TKAs at the time of surgery based on perceived technical quality of surgery.

Patients and Methods We reviewed all 1050 patients undergoing 1193 primary TKAs performed by a single surgeon between 2000 and 2004. The surgeon intraoperatively recorded his impression of the technical quality of surgery based on 15 factors (on a 1-10 scale, with 10 being highest quality) and degree of difficulty (on a 1-10 scale, with 10 being most difficult). We correlated these impressions to KSSs. One hundred thirty-nine of the 1050 patients had technical quality scores of less than 8, including 15 knees with major technical downgrades with clear deficiencies we presumed would affect outcomes. Minimum followup was 24 months (mean, 48 months; range, 24-60 months).

Results We found no difference in mean KSSs between the 1054 TKAs with technical quality scores of more than 8 and the 124 knees with technical quality scores of less than 8. However, mean KSSs were lower in the 15 knees with technical quality scores of less than 6.5 than in the 124 knees with technical quality scores of less than 8, but these 15 knees also had a higher degree of difficulty than the 124 knees.

Conclusions The surgeon’s subjective view of technical quality of surgery did not predict KSSs unless the technical quality score was extremely low. More than one technical problem was associated with lower scores. It is unclear whether this is a question of the subjective ratings or our inability to define quality.

Level of Evidence Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.