133 / 242
133
Background
When performing total knee arthroplasty
(TKA) in the setting of osteoarthritis with
valgus deformities, the surgeon can choose
whether to approach the joint via a standard
medial parapatellar approach, or via a lateral
parapatellarapproach.Keblish[4]recommended
a lateral parapatellar approach for knees with a
fixed valgus deformity as this method provides
direct access to the lateral structures, facilitating
ligament balance. But for many authors, the
lateral approach is considered difficult, and is
associated with greater complication rates. The
purpose of this single center study was to
compare surgical factors and short-term clinical
and radiographic outcomes of the medial and
lateral approach for TKA in knees with
moderate valgus (<10°).
Methods
Four hundred and twenty four knees undergoing
TKA with a pre-operative valgus deformity
between 3 and 10 degrees were identified
through queries of a prospectively collected
TKA database. 109 knees were treated via a
medial approach and 315 knees were treated
via a lateral approach. The Tornier HLS TKA
system was used for all knees. Intra-operative
variables that were assessed included surgical
time, tourniquet time, the type of lateral releases
that were performed, and whether a tibial
tubercle osteotomy was required. International
Knee Society (IKS) knee and functional scores
and radiographic alignment were compared
post-operative with a minimum of two years
follow-up. Fisher’s exact tests were used to
compare categorical variables, and
t
-tests were
used for continuous variables, with statistical
significance defined as p < 0.05.
Results
Tourniquet time (p=0.25) and surgical time
(p=0.62) were not significantly different
between the two groups. The popliteus tendon
was released more frequently in the medial
approach group (p=0.04), while the iliotibial
band was released more frequently in the lateral
approach group (p<0.001). A tibial tuberosity
osteotomy was performed more frequently in
the lateral approach group than in the medial
approach group (20.8% vs 8%).
At final follow-up, no significant differences in
limb alignment (p=0.78), IKS knee (p=0.32) or
function (p=0.47) scores were noted based on
surgical approach. The complication rates were
similar in the two groups (p=0.53).
Medial Versus Lateral
Parapatellar Approach for
Total Knee Arthroplasty in
Patients with Moderate
Valgus Deformity
R.A. Magnussen, S. Gunst, V. Villa, C. Debette,
O. Reynaud, E. Servien, S. Lustig, P. Neyret