Abstract
The mini-midvastus (MV) approach to total knee arthroplasty (TKA) minimizes damage
to the extensor mechanism; however, the mini-subvastus (SV) approach is designed to
avoid such damage. Quadriceps weakness following TKA can have a significant impact
on the activities of daily living, particularly stand-to-sit down (STSD) and sit-to-stand
up (STSU) activities. Fifty-three subjects diagnosed with primary osteoarthritis and
scheduled to undergo TKA were randomized to receive an MV or SV surgical approach
and were given identical postoperative orders. Compared with age-matched controls,
the SV group had a quicker return of normal peak knee extension moment during STSU,
whereas the MV group had a quicker return of normal movement patterns in hip, knee,
and ankle parameters during STSD yet represented the higher functioning subjects as
more MV subjects had difficulty completing the task as instructed. Considering both
movements are required for daily living, neither surgical group was found to have
a significant advantage over the other in functional outcome through 6 months post-TKA.
Keywords
total knee arthroplasty - sit-to-stand - midvastus - subvastus - quadriceps weakness
