TY - JOUR
T1 - Lower limb alignment and laxity measures before, during and after total knee arthroplasty
T2 - a prospective cohort study
AU - Clarke, Jon V.
AU - Deakin, Angela H.
AU - Picard, Frederic
AU - Riches, Philip E.
PY - 2017/5/26
Y1 - 2017/5/26
N2 - Background. This study compared knee alignment and laxity in patients before, during and after total knee arthroplasty, using methodologically similar procedures, with an aim to help inform pre-operative planning.Methods. Eighteen male and 13 female patients were recruited, mean age 66 years (51-82) and mean body mass index of 33 (23-43). All were assessed pre- and postoperatively using a non-invasive infrared position capture system and all underwent total knee arthroplasty using a navigation system. Knee kinematic data were collected and comparisons made between preoperative clinical and intraoperative measurements for osteoarthritic knees, and between postoperative clinical and intraoperative measurements for prosthetic knees. Findings. There was no difference in unstressed coronal mechanical femoral-tibial angles for either osteoarthritic or prosthetic knees. However, for sagittal alignment the knees were in greater extension intraoperatively (osteoarthritic 5.2° p<0.001, prosthetic 7.2° p<0.001). For osteoarthritic knees, both varus and valgus stress manoeuvres had greater angular displacements intraoperatively by a mean value of 1.5° for varus (p=0.002) and 1.6° for valgus (p<0.001). For prosthetic knees, only valgus angular displacement was greater intraoperatively (0.9°, p=0.002).
AB - Background. This study compared knee alignment and laxity in patients before, during and after total knee arthroplasty, using methodologically similar procedures, with an aim to help inform pre-operative planning.Methods. Eighteen male and 13 female patients were recruited, mean age 66 years (51-82) and mean body mass index of 33 (23-43). All were assessed pre- and postoperatively using a non-invasive infrared position capture system and all underwent total knee arthroplasty using a navigation system. Knee kinematic data were collected and comparisons made between preoperative clinical and intraoperative measurements for osteoarthritic knees, and between postoperative clinical and intraoperative measurements for prosthetic knees. Findings. There was no difference in unstressed coronal mechanical femoral-tibial angles for either osteoarthritic or prosthetic knees. However, for sagittal alignment the knees were in greater extension intraoperatively (osteoarthritic 5.2° p<0.001, prosthetic 7.2° p<0.001). For osteoarthritic knees, both varus and valgus stress manoeuvres had greater angular displacements intraoperatively by a mean value of 1.5° for varus (p=0.002) and 1.6° for valgus (p<0.001). For prosthetic knees, only valgus angular displacement was greater intraoperatively (0.9°, p=0.002).
KW - total knee arthroplasty
KW - lower limb alignment
KW - soft tissue laxity
KW - non-invasive infrared tracking
KW - computer assisted surgery
UR - http://www.sciencedirect.com/science/journal/02680033
U2 - 10.1016/j.clinbiomech.2017.05.013
DO - 10.1016/j.clinbiomech.2017.05.013
M3 - Article
JO - Clinical Biomechanics
JF - Clinical Biomechanics
SN - 0268-0033
ER -