Table II.
Clinical scores.
| Variable | TKA | bi-UKA | p-value* |
|---|---|---|---|
| Median NKSS knee (IQR) | |||
| Preoperative | 41 (37.5 to 47.5) | 42 (36.5 to 50.0) | 0.602* |
| 3 mths | 48 (41.5 to 53.0) | 46 (38 to 52) | 0.838* |
| 1 yr | 51.5 (42 to 56) | 48 (43.0 to 55.5) | 0.635* |
| Median NKSS function (IQR) | |||
| Preoperative | 52 (40.0 to 73.5) | 56 (44.75 to 80.5) | 0.379* |
| 3 mths | 102 (80.5 to 120.0) | 90 (67 to 115) | 0.318* |
| 1 yr | 109.5 (82.5 to 137.5) | 102.5 (77.0 to 120.8) | 0.085* |
| Median NKSS total (IQR) | |||
| Preoperative | 99 (81.0 to 118.5) | 102 (81.2 to 124.3) | 0.369* |
| 3 mths | 148 (122.0 to 170.5) | 140 (115 to 166) | 0.384* |
| 1 yr | 159 (127.5 to 192.8) | 156 (119.3 to 167.3) | 0.122* |
| Median OKS (IQR) | |||
| Preoperative | 18.5 (14.00 to 26.75) | 19 (14.0 to 25.5) | 0.751 |
| 3 mths | 35 (27 to 42) | 34 (25 to 39) | 0.523 |
| 1 yr | 37 (29 to 45) | 39 (30.5 to 43.0) | 0.970 |
| Mean pain VAS (SD) | |||
| Preoperative | 7.0 (2.0) | 6.6 (2.2) | 0.744 |
| 3 mths | 2.1 (2.0) | 2.4 (2.4) | 0.932 |
| 1 yr | 1.9 (1.9) | 1.6 (2.0) | 0.443 |
| Mean stiffness VAS (SD) | |||
| Preoperative | 6.9 (2.1) | 6.6 (2.0) | 0.374 |
| 3 mths | 3.2 (2.4) | 3.1 (2.2) | 0.938 |
| 1 yr | 2.4 (2.3) | 2.1 (2.3) | 0.357 |
| Median FJS (IQR) | |||
| Preoperative | N/A | N/A | N/A |
| 3 mths | 16 (5.5 to 24.0) | 12 (4 to 25) | 0.961 |
| 1 yr | 20.5 (10.25 to 28.75) | 19.0 (14.25 to 31.00) | 0.525 |
| Mean EQ-5D-3L VAS (SD) | |||
| Preoperative | 69.8 (16.91) | 72.2 (15.3) | 0.491 |
| 3 mths | 82.5 (12.56) | 78.0 (21.18) | 0.768 |
| 1 yr | 78.9 (15.7) | 74.9 (22.3) | 0.723 |
| Mean EQ-5D-3L index (SD) | |||
| Preoperative | 0.45 (0.31) | 0.44 (0.30) | 0.896 |
| 3 mths | 0.71 (0.27) | 0.68 (0.3) | 0.395 |
| 1 yr | 0.76 (0.21) | 0.73 (0.32) | 0.638 |
| Mean ROM, ° (SD) | |||
| Preoperative | 95.6 (23.3) | 101.1 (18.7) | 0.407* |
| 3 mths | 96.0 (20.0) | 95.2 (14.21) | 0.392* |
| 1 yr | 110.7 (9.4) | 107.1 (12.9) | 0.369* |
| Median UCLA activity scale (IQR) | |||
| Preoperative | 3 (3 to 4) | 3 (3 to 5.25) | 0.359 |
| 3 mths | 4 (3 to 6) | 4 (3 to 6) | 0.796 |
| 1 yr | 5 (4 to 6) | 5.5 (3 to 6) | 0.734 |
| Satisfied, Y:N | |||
| Preoperative | N/A | N/A | N/A |
| 3 mths | 32:9 | 23:8 | 0.702‡ |
| 1 yr | 32: 9 | 28:4 | 0.295‡ |
| Mean Timed Up and Go, secs (SD) | |||
| Preoperative | 14.2 (8.3) | 14.1 (6.2) | 0.665 |
| 3 mths | 10.5 (2.8) | 13.2 (11.6) | 0.550 |
| 1 yr | 11.2 (5.9) | 10.9 (5.6) | 0.914 |
| Mean Stair Climb Test, secs (SD) | |||
| Preoperative | 28.0 (14.2) | 26.0 (13.2) | 0.667 |
| 3 mths | 24.2 (12.3) | 22.5 (8.2) | 0.805 |
| 1 yr | 19.8 (9.1) | 17.1 (6.6) | 0.271 |
| Mean quadricep strength, Nm (SD) | |||
| Preoperative | 71.1 (37.8) | 78.5 (33.0) | 0.261 |
| 3 mths | N/A | N/A | N/A |
| 1 yr | 91.5 (39.6) | 85.6 (32.1) | 0.568 |
*
Independent-samples t-test.
†
Mann-Whitney U test.
‡
Chi-squared test.
bi-UKA, bi-unicompartmental knee arthroplasty; EQ-5D-3L, EuroQol five-dimension three-level questionnaire; FJS, Forgotten Joint Score; IQR, interquartile range; N/A, not available; NKSS, New Knee Society Score; Nm, Newton metres; OKS, Oxford Knee Score; ROM, range of motion; SD, standard deviation; TKA, total knee arthroplasty; UCLA, University of California, Los Angeles; VAS, visual analogue scale.