title: Using pre-operative MRI to predict intraoperative hamstring graft size for anterior cruciate ligament reconstruction.
abstract: OBJECTIVE
  Large variation in tendon size between individuals makes hamstring graft diameter for anterior cruciate ligament (ACL) reconstruction unpredictable. Inadequate graft diameter may necessitate an alternative source of tissue requiring pre-operative planning. The purpose of this study was to determine whether magnetic resonance image (MRI) measurements and clinical anthropometric data are predictive of hamstring tendon graft diameter.
  
  
  METHODS
  Data from 109 patients having ACL reconstruction with semitendinosus-gracilis (STGT) autograft were retrospectively evaluated. Cross-sectional area (CSA) of the gracilis tendon (GT) and semitendinosus tendon (ST) were determined from pre-operative MRI scans. Variables included pre-operative height, weight, body mass index (BMI), age and gender; and intra-operative graft diameter.
  
  
  RESULTS
  Correlations between anthropometric variables, hamstring tendons CSA and intra-operative graft diameter were calculated. Multiple stepwise regression was performed to assess the predictive value of these variables to graft diameter. Sensitivity and specificity were calculated to evaluate the utility of MRI CSA measurements in accurately identifying inadequate graft diameter (<8 mm). All anthropometric variables were positively correlated with intraoperative graft diameter (p < 0.01). Semitendinosus-gracilis tendon CSA (p < 0.001) and STGT CSA and weight (p < 0.001) were significantly predictive models of graft diameter. Sensitivity and specificity were 79 and 74 %, respectively.
  
  
  CONCLUSIONS
  The strongest indicators of a four-stranded STGT graft for primary ACL reconstruction were STGT CSA on MRI plus weight. Measurement of graft diameter can be performed pre-operatively via MRI to identify tendons that may be of inadequate size for ACL reconstruction. This can assist with surgical planning to determine the most appropriate graft choice.
  
  
  METHODS
  III.
authors.affiliation: Department of Surgery, University of Manitoba, Winnipeg, Canada. jleiter@panamclinic.com.|Pan Am Clinic Foundation, 75 Poseidon Bay, Winnipeg, MB, R3M 3E4, Canada. jleiter@panamclinic.com.
authors.forename: Jeff
authors.initials: J
authors.lastname: Leiter
authors.affiliation: Department of Surgery, University of Manitoba, Winnipeg, Canada.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Elkurbo
authors.affiliation: Pan Am Clinic Foundation, 75 Poseidon Bay, Winnipeg, MB, R3M 3E4, Canada.
authors.forename: Sheila
authors.initials: S
authors.lastname: McRae
authors.affiliation: Department of Surgery, University of Manitoba, Winnipeg, Canada.|Pan Am Clinic, Winnipeg, Canada.
authors.forename: James
authors.initials: J
authors.lastname: Chiu
authors.affiliation: Pan Am Clinic, Winnipeg, Canada.
authors.forename: Warren
authors.initials: W
authors.lastname: Froese
authors.affiliation: Department of Surgery, University of Manitoba, Winnipeg, Canada.|Pan Am Clinic, Winnipeg, Canada.
authors.forename: Peter
authors.initials: P
authors.lastname: MacDonald
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries / Q000000981:diagnostic imaging / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D000886:Anthropometry; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D000070633:Hamstring Muscles / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D000070632:Hamstring Tendons / Q000000981:diagnostic imaging* / Q000473:pathology / Q000637:transplantation; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D012189:Retrospective Studies; D014182:Transplantation, Autologous; D055815:Young Adult
keywords: ACL; Autograft; Gracilis; MRI; Pre-operative planning; Semitendinosus