[Comparison of clinical results between high-flexion and standard cruciate-stabling prostheses in total knee arthroplasty].

OBJECTIVE

To compare the clinical results between high-flexion and standard cruciate-stabling prostheses in total knee arthroplasty (TKA) by using the 36-item short form health survey (SF-36).

METHODS

Between August 2007 and January 2009, 98 patients (106 knees) underwent TKA with standard cruciate-stabling prostheses (standard group), and 46 patients (50 knees) underwent TKA with high-flexion prostheses (high-flexion group). In standard group, there were 30 males (32 knees) and 68 females (74 knees) with an age of (70.0 +/- 3.5) years, including 78 cases (82 knees) of osteoarthritis (OA) and 20 cases (24 knees) of rheumatoid arthritis (RA) with a disease duration of (14.5 +/- 3.3) years; the Hospital for Special Surgery Scoring System (HSS) and the range of motion (ROM) were 56.1 +/- 21.6 and (89.0 +/- 16.1) degrees, respectively. In high-flexion group, there were 8 males (10 knees) and 38 females (40 knees) with an age of (68.6 +/- 8.9) years, including 44 cases (47 knees) of OA and 2 cases (3 knees) of RA with a disease duration of (13.9 +/- 4.1) years; the HSS and ROM were 58.9 +/- 25.3 and (91.0 + 19.3) degrees, respectively. There was no significant difference in the general data (P > 0.05) between 2 groups, so the clinical data of 2 groups had comparability.

RESULTS

In standard group, poor wound healing and persistent headache caused by cerebrospinal fluid leakage occurred in 1 case, respectively. In high-flexion group, transient common peroneal nerve palsy occurred in 1 case. There was significant difference (P < 0.05) in the hospitalization expense between standard group [yen(39,000 +/- 6000)] and high-flexion group [yen (52,000 +/- 8 000)]. The follow-up time was 12-26 months (18 months on average) in standard group (91 cases, 98 knees) and 11-19 months (13 months on average) in high-flexion group (44 cases, 47 knees). The SF-36 showed significant difference in role-physical score (P < 0.05), but no significant difference in other 7 indices scores (P > 0.05). At the final follow- up, the ROM was (129.1 +/- 19.2) degrees in high-flexion group and (123.6 +/- 16.7) degrees in standard group; showing significant difference (P < 0.05). The HSS was 91.2 +/- 17.6 in high-flexion group and 92.5 +/- 14.5 in standard group; showing no significant difference (P > 0.05).

CONCLUSION

After TKA, the ROM in high-flexion group is superior to that in standard group, but there is no obvious advantages in terms of the HSS and SF-36 outcomes.