Subvastus approach for total knee arthroplasty: a prospective, randomized, and observer-blinded trial.

A prospective, randomized, and blinded trial was conducted with 89 consecutive primary knee arthroplasties comparing standard medial parapatellar arthrotomy with the subvastus approach. All patients received the same prosthesis (Insall-Burstein II) inserted by one surgeon using an identical technique with the only difference being the approach. The parapatellar approach (group I) was used in 43 knees, and in the remaining 46 knees the subvastus approach (group II) was used. Assessment revealed significantly earlier return of straight-leg raise (3.2 days vs 5.8 days, P <.001), lower consumption of opiates in the first week (78 mg vs 102 mg, P <.001), less blood loss (527 mL vs 748 mL, P <.001), and greater knee flexion at 1 week (78 degrees vs 55 degrees, P <.001) in group II (subvastus approach). The subvastus approach offers early advantages over the standard parapatellar arthrotomy. It preserves the integrity of the vastus medialis and peripatellar plexus of vessels. We advise its wider use in primary total knee arthroplasty.