The aim of this study was to assess the results of bilateral total knee replacement (TKR) staged one week apart during one hospital admission and compare these results with those of bilateral sequential TKRs and bilateral TKRs performed in 2 separate admissions by a single surgeon using a single prosthesis. Between 5th November 1997 and 10th August 2004, 104 patients underwent bilateral LCS TKRs using the Anteroposterior glide (APG) tibial component. The patients were analysed in 3 groups. The patients in Group 1 underwent bilateral sequential TKR under the same anaesthetic. The patients in Group 2 underwent bilateral TKRs under 2 separate anaesthetics, 7 days apart, during the same admission. The patients in Group 3 underwent bilateral TKR under 2 separate admissions, essentially 2 unilateral TKRs. The patients in Group 1 had shorter operations (p<
0.0001) and shorter hospital stays (p<
0.0001). Patients in Group 2 had less blood loss (p=0.004) but were not transfused any less than the other groups. The complication rate was low and comparable in all groups. There were no in hospital or 30 day deaths in any of the groups. Those patients in Group 3 had worse AKS function scores (p=0.02) and those patients in Group 2 had a significantly better HSS score (p=0.02). There was no significant difference between the groups in terms of range of motion or the AKS Knee score. This study has confirmed a shorter operation and hospital stay when the bilateral TKRs are carried out under the same anaesthetic. These patients also bled the most postoperatively. There was little difference in terms of complications and clinical outcome at a mean follow up of 4 years. With appropriate patient selection, both same anaesthetic and same admission bilateral TKR are safe methods to treat bilateral arthritis.
Average estimated peri-operative blood loss for the standard incision group was 3.45 units and for the minimal incision group was 3.05 units (statistically significant, p-value 0.039, 95%CI). One patient after minimal incision had a superficial wound infection, which responded to oral antibiotics. There was one dislocation (standard incision).
The overall 1-year mortality was 31.4% (235/748) and the sex distribution (male 73/153 [47.7%] female 162/595 [27.2%]). 27/748 patients who did not undergo surgical intervention had a 1-year mortality of 85.2%. Factors which were associated with an increased 1 year mortality were: male sex (p<
0.0005), High ASA score (p<
0.0005), low Barthel score (p<
0.0005), poor mental score (p<
0.0005), decreased mobility (p<
0.0005), increased dependency in home circumstances (p<
0.0005), increased age (p<
0.0005), increased delay to surgery (p<
0.0005) and living alone (p<
0.0005). Marital status, fracture type and type of operative intervention had no statistical effect on mortality. Using logistic regression male sex, high ASA score, increased age, increased delay to surgery and poor mental score all remained independently associated with an increased mortality at 1 year.