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Updated: Feb 5, 2026

Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
No differences in patient-reported outcomes between medial pivot insert and symmetrical insert in total knee
Kohei Nishitani1, Moritoshi Furu1, Shinichiro Nakamura1
1Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Background:
Although total knee arthroplasty (TKA) using a medial pivot insert reportedly improves kinematics compared with a symmetrical insert, improvements in patient-reported outcomes have not yet been reported. The aim of this study was to determine whether insert designs influenced patient-reported outcomes.
Methods:
Seventy TKAs for osteoarthritis were randomly allocated to a symmetrical dish insert (SD group: 35 knees) or medial pivot insert (MP group: 35 knees). Thirty-two of the SD group (74.4 ± 6.6 years old) and 33 of the MP group (73.8 ± 6.0 years old) completed the two-year follow-up. The knee range of motion (ROM) and 2011 Knee Society score (2011KSS) were analyzed pre-operatively and postoperatively.
Results:
There was no difference in pre-operative ROM or 2011KSS (Symptom: 7.3 ± 5.9 in SD group, 8.4 ± 5.4 in MP group, P = 0.432; Satisfaction: 12.6 ± 6.9 in SD group, 11.8 ± 5.9 in MP group, P = 0.581; Activity: 35.8 ± 18.1 in SD group, 35.2 ± 18.6 in MP group, P = 0.883). At two years, although both group showed good improvement, there were no differences in ROM or 2011KSS (Symptom: 19.3 ± 5.0 in SD group, 18.3 ± 4.1 in MP group, P = 0.351; Satisfaction: 24.0 ± 7.6 in SD group, 22.9 ± 7.9 in MP group, P = 0.548; Activity: 60.3 ± 14.8 in SD group, 54.3 ± 17.3 in MP group, P = 0.137).
Conclusions:
The medial pivot insert was not superior to the symmetrical insert in patient-reported outcomes at two years after TKA.
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