Achieving high flexion after total knee arthroplasty (TKA) is one of the most important clinical results, especially in eastern countries where the high flexion activities, such as kneeling and squatting, are part of the important lifestyle. Numerous studies have examined the kinematics after TKA. However, there are few numbers of studies which examined the kinematics during deep knee flexion activities. Therefore, in the present study, we report analysis of mobile-bearing TKA kinematics from extension to deep flexion kneeling using 2D-3D image matching technique. The subjects were 16 knees of 8 consecutive patients (all women, average age 75.9), who underwent primary mobile-bearing PS TKA (P.F.C. sigma RP-F: Depuy Orthopedics Inc., Warsaw, IN, USA) between February 2007 and May 2008. All cases were osteoarthritis with varus deformity. Postoperative radiographs were taken at the position of extension, half-squatting and deep flexion kneeling 3 month after the surgery, and the degrees of internal rotation of the tibial component was measured by 2D-3D image matching technique. Pre- and post-operative ROM was recorded. Then, we compared the absolute value and relative movement of tibial internal rotation between extension, half-squatting and deep flexion kneeling, and evaluated the correlation of the ROM and the internal rotation.Introduction
Materials and Methods
We evaluated the maturation of grafted bone in
cases of successful fusion after a one- or two-level posterior lumbar interbody
fusion (PLIF) using interbody carbon cages. We carried out a five-year
prospective longitudinal radiological evaluation of patients using
plain radiographs and CT scans. One year after surgery, 117 patients
with an early successful fusion were selected for inclusion in the
study. Radiological evaluation of interbody bone fusion was graded
on a 4-point scale. The mean grades of all radiological and CT assessments
increased in the five years after surgery, and differences compared
to the previous time interval were statistically significant for
three or four years after surgery. Because the grafted bone continues
to mature for three years after surgery, the success of a fusion
should not be assessed until at least three years have elapsed.
There were no significant differences in the longitudinal patterns
of grafted bone maturity between iliac bone and local bone. However,
iliac bone grafting may remodel faster than local bone.
