Progressive coxa vara by eccentric growth tethering in immature pigs.
The present study tested progressive coxa vara by eccentric growth tethering that might be used to correct coxa valga in cerebral palsy. Eight young pigs received screw fixation at inferior portion of right femoral head at age 4 months and were killed at age 7.25 months for bilateral femurs for comparison. The neck-shaft angle at the tethered side was significantly less than that at the control side (129.8 vs. 138.3 degrees , P<0.05). Histological study showed bony bar formation. Eccentric growth tethering by one screw resulted in a reduction of neck-shaft angle by 8.5 degrees and shortening of femoral length by 4%.
Chang
Chia-Hsieh
CH
Department of Orthopedic Surgery, Chang Gung Children Hospital, Taoyuan, National Taiwan University, Taipei, Taiwan. chiahchang@yahoo.com.tw
Chi
Chau-Hwa
CH
Lee
Zhon-Liau
ZL
D000818:Animals; D001863:Bone Screws; D005269:Femur / Q000473:pathology*; D005270:Femur Head / Q000473:pathology; D007103:Immobilization / Q000662:veterinary*; D023421:Models, Animal; D013552:Swine / Q000254:growth & development*; D013553:Swine Diseases / Q000209:etiology