BACKGROUND:
In 1985, the senior author (C.S.R.) developed a new soft-tissue release
technique to balance valgus knees to avoid unacceptably high rates of
late-onset instability and the need for primary constrained implants. This
report describes the soft-tissue release technique and its long-term results
when performed in primary total knee arthroplasty in patients with a severe
valgus knee deformity.
METHODS:
Four hundred and ninety consecutive total knee arthroplasties were
performed by one surgeon between January 1988 and December 1992. In this
group, seventy-one patients (eighty-five knees) had a valgus deformity of
10°. Thirty-two patients (thirty-six knees) died, and four patients (seven
knees) were lost to follow-up, leaving thirty-five patients (forty-two knees)
followed for a minimum of five years. These twenty-seven women and eight men
had a mean age of sixty-seven years at the time of the index operation. The
technique included an inside-out soft-tissue release of the posterolateral
aspect of the capsule with pie-crusting of the iliotibial band and resection
of the proximal part of the tibia and distal part of the femur to provide a
balanced, rectangular space. Cemented, posterior stabilized implants were used
in all knees. Clinical and radiographic evaluations were performed at one,
five, and ten years postoperatively.
RESULTS:
The mean modified Knee Society clinical score improved from 30 points
preoperatively to 93 points postoperatively, and the mean functional score
improved from 34 to 81 points. The mean range of motion was 110° both
preoperatively and postoperatively. The mean coronal alignment was corrected
from 15° of valgus preoperatively to 5° of valgus postoperatively.
Three patients underwent revision surgery because of delayed infection,
premature polyethylene wear, and patellar loosening in one patient each. There
were no cases of delayed instability.
CONCLUSIONS:
The inside-out release technique to correct a fixed valgus deformity in
patients undergoing primary total knee arthroplasty is reproducible and
provides excellent long-term results.