Abstract
A significant number of patients are affected by localized articular damage that is
appropriate neither for traditional arthroplasty nor for biological repair. A focal
resurfacing system using a matched contoured articular prosthetic (HemiCAP) has been
introduced for the treatment of such cases. Independent long-term results of these
implants are limited. We retrospectively evaluated the use of this resurfacing system
in 14 patients (13 males, 1 female), with a mean age of 40.3 years (range: 28–49),
with focal femoral condyle defects. The same consultant orthopaedic surgeon performed
all procedures. Our primary outcome measure was revision rate. Secondary outcome measures
included radiographic evaluation (prosthesis migration signs, radiolucency), patient-reported
functional evaluation (knee injury and osteoarthritis outcome scores), and complications.
A total of 10 patients were treated on the medial femoral condyle, 2 were treated
on the lateral condyle, and 2 received bicondylar implants (14 in total). Average
follow-up was 107 months (range: 59–135). Three patients were lost to follow-up at
the time of study. One patient was excluded from the study. Of the 10 left, 2 had
to be revised, leading the survival rate to be 80% at 9.4 years. In four contactable
patients, average Knee injury and Osteoarthritis Outcomes score at 121 months postsurgery
(9.75 years) was 92.9 (as compared with 57.7 preoperatively). There were no complications.
This series demonstrates that focal resurfacing is a safe, suitable, and useful temporizing
step in knee arthroplasty surgery. The use of the focal resurfacing implant in this
way allows the delay in transition to knee arthroplasty. This series shows an excellent
functional outcome for remaining implants at average 10 years, with low complication
rates.
Keywords
HemiCAP - osteochondral plug - osteoarthritis - knee
