We investigated changes in the axial alignment of the ipsilateral
hip and knee after total hip arthroplasty (THA). We reviewed 152 patients undergoing primary THA (163 hips; 22
hips in men, 141 hips in women) without a pre-operative flexion
contracture. The mean age was 64 years (30 to 88). The diagnosis
was osteoarthritis (OA) in 151 hips (primary in 18 hips, and secondary
to dysplasia in 133) and non-OA in 12 hips. A posterolateral approach
with repair of the external rotators was used in 134 hips and an
anterior approach in 29 hips. We measured changes in leg length
and offset on radiographs, and femoral anteversion, internal rotation
of the hip and lateral patellar tilt on CT scans, pre- and post-operatively. Aims
Patients and Methods
Obtaining a balanced flexion gap with correct
femoral component rotation is one of the prerequisites for a successful
outcome after total knee replacement (TKR). Different techniques
for achieving this have been described. In this study we prospectively
compared gap-balancing versus measured resection
in terms of reliability and accuracy for femoral component rotation
in 96 primary TKRs performed in 96 patients using the Journey system.
In 48 patients (18 men and 30 women) with a mean age of 65 years
(45 to 85) a tensor device was used to determine rotation. In the
second group of 48 patients (14 men and 34 women) with a mean age
of 64 years (41 to 86), an ‘adapted’ measured resection technique
was used, taking into account the native rotational geometry of
the femur as measured on a
pre-operative CT scan. Both groups systematically reproduced a similar external rotation
of the femoral component relative to the surgical transepicondylar
axis: 2.4° . (sd. 2.5) in the gap-balancing group and 1.7°
(. sd. 2.1) in the measured resection group (p = 0.134). Both
gap-balancing and adapted measured resection techniques proved equally
reliable and accurate in determining femoral component rotation
after TKR. There was a tendency towards more
