title: Treatment of patella fracture by claw-like shape memory alloy.
abstract: BACKGROUND
  Titanium-nickel shape memory alloy (Ti-Ni SMA) is characterized by shape-memory effect, super-elasticity, excellent fatigue behavior, corrosion resistance, acceptable biocompatibility and high damping capacity.
  
  
  METHODS
  Claw-like Ti-Ni SMA fixator (SMA-claw) has been used to treat transverse fracture of patella. 29 patients (19 males, 10 females) aged from 21 to 71 years old (averaged 43.0 years old) have been received open reduction and internal fixation with SMA-claw from January 2011 to December 2011. After operation, patients have been received gradual knee function exercises, followed by radiographic analysis and Lysholm Knee Score at 1, 2, 3, 6, 9 and 12 months postoperation.
  
  
  RESULTS
  The mean follow-up time was 11.48 months (25 patients finished, 1 lost after 6 months and 3 lost after 9 months). Radiographic bone union occurred at 2 months (7 patients) or 3 months (22 patients). Satisfied range of motion for the knee joint has been observed with 1.90/141.72° (hyperextension/flexion) at 3 months, 4.83/143.97° at 6 months, 4.82/144.82° at 9 months and 5.2/145° at 12 months postsurgery.
  
  
  CONCLUSIONS
  The Ti-Ni SMA-claw fixator produced good osteosynthesis effect by continuous recovery stress with relatively simple and minimally invasive handling process, which can be introduced as an alternative to traditional tension band technique for treatment of patellar transverse fracture.
authors.affiliation: Department of Orthopaedics and Traumatology, Yan'tai YuHuangDing Hospital Affiliated to Qingdao University Medical College, Yan'tai, 264000, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hao
authors.forename: Lugang
authors.initials: L
authors.lastname: Zhou
authors.forename: Yujie
authors.initials: Y
authors.lastname: Sun
authors.forename: Peng
authors.initials: P
authors.lastname: Shi
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Liu
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000497:Alloys; D001860:Bone Plates; D004867:Equipment Design; D005260:Female; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods; D017102:Fracture Healing; D050723:Fractures, Bone / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009532:Nickel; D010329:Patella / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D011446:Prospective Studies; D011859:Radiography; D016059:Range of Motion, Articular; D020127:Recovery of Function; D014025:Titanium; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000497:Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium