[Are There any Differences in Quality or Complication Rate in Total Knee Arthroplasty after Establishing a Centre for Endoprosthesis?].

Background: The aim of the study is to show whether there are any changes in quality or incidence of complications in total knee arthroplasty (TKA) after establishing a centre for endoprothesis (EPZ).

Material And Methods: We conducted a retrospective study comparing 100 TKAs one year before establishing an EPZ (Group I) with 100 TKAs one year after establishing an EPZ (group II). Data were collected by analysing our electronic documentation system, and the report of the rehabilitation hospital. The following parameters were documented which are necessary to establish an EPZ: existence of X-rays before and after operation. Existence of full length weight bearing X-ray before operation or using a navigation device. Existence of preoperative planning, duration of TKA below 100 minutes. The following complications were documented: Periprosthetic infections, occurrence of periprosthetic fissures/fractures, thrombembolism, neurologic complications, patients' satisfaction rate with the hospital stay and mortality rate. Additionally femorotibial angle, femoral angle, tibial angle and tibial slope were measured. Statistical analysis was performed with SPSS 22.0. using the Kolmogorov-Smirnov test, the Qui-Square test and the Mann-Whitney U test.

Results: There were no statistical differences in local or systemic complications. The mean duration of operation was 82.9 min in group I (min.: 55, max.: 141) und 81.5 min in group II (min.: 57, max.: 129; p > 0.05). In group I, there were 20/100 cases (20%) with operation time longer than 100 minutes, in group II 13/100 cases (13%; p < 0.001). Analysis of anatomical femorotibial angle, femur angle, tibial angle and tibial slope showed no significant differences. The rate of documented survey of patients' satisfaction rate improved from 62% in group I to 98% in group II (p < 0.001).

Conclusion: By establishing an EPZ, we achieved a significant improvement in the parameters operation time > 100 minutes and documented survey of patients' satisfaction rate, but not in complication rate.