title: Muscle function and functional outcome following standard antegrade reamed intramedullary nailing of isolated femoral shaft fractures.
abstract: OBJECTIVE
  To evaluate the functional outcomes and long-term effects on muscle strength of femoral shaft fractures treated with intramedullary (IM) antegrade nailing using a standard piriformis start point.
  
  
  METHODS
  Retrospective Outcome Study.
  
  
  METHODS
  Tertiary Level Teaching Hospital and Referral Centre for the Province of British Columbia.
  
  
  METHODS
  Twenty-one patients (7 female, 14 male; mean age 34.5 years, range 16-56 years) with isolated femoral shaft fractures who were treated with standard antegrade reamed interlocking IM nailing and who had a minimum 1-year follow-up were identified through the Orthopaedic Trauma Database. All patients had isokinetic muscle testing of their hip abductors, hip extensors, and knee extensors using the KinCom muscle testing machine. Of the patients, 10 underwent formal gait lab analysis. All of the patients answered a questionnaire and completed the Short Form (SF)-36 and Musculoskeletal Functional Assessment outcome measures.
  
  
  METHODS
  Antegrade reamed interlocking IM nailing of femoral shaft fractures using a standard trochanteric fossa (also referred to as piriformis fossa) starting point.
  
  
  METHODS
  Examination of muscle strength, using 2 different objective measures (KinCom and gait analysis). The KinCom muscle testing machine was used for isokinetic muscle testing of hip abductors, hip extensors, and knee extensors. Outcome questionnaires were used to evaluate function (Musculoskeletal Functional Assessment) and general health (SF-36).
  
  
  RESULTS
  Isokinetic muscle testing showed a statistically significant lower peak torque generation by the hip abductors (P=0.003) and hip extensors (P=0.046) from the uninjured contralateral side. The gait lab analysis did not show important changes in gait pattern. Scores for the SF-36 were 51.77+/-7.55 and 53.73+/-8.70. Scores for the Short Musculoskeletal Functional Assessment (S-MFA) were 7.74 and 8.66. Both scores did not indicate any significant disability.
  
  
  CONCLUSIONS
  Antegrade reamed interlocking IM nailing of femoral shaft fractures using a standard trochanteric fossa starting point is associated with a mild hip abductor muscle-strength deficit. Gait pattern returns to normal following femoral shaft fracture treated with this technique, and functional outcomes are good.
authors.affiliation: Department of Orthopaedics, Balgrist University Hospital, Forchstrasse, Zurich.
authors.forename: Nader
authors.initials: N
authors.lastname: Helmy
authors.forename: Victor T
authors.initials: VT
authors.lastname: Jando
authors.forename: Thomas
authors.initials: T
authors.lastname: Lu
authors.forename: Holman
authors.initials: H
authors.lastname: Chan
authors.forename: Peter J
authors.initials: PJ
authors.lastname: O'Brien
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D001858:Bone Nails; D005260:Female; D005264:Femoral Fractures / Q000503:physiopathology* / Q000534:rehabilitation / Q000601:surgery; D005594:Fracture Fixation, Intramedullary / Q000295:instrumentation* / Q000379:methods; D017102:Fracture Healing / Q000502:physiology; D005684:Gait; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D053580:Muscle Strength; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000503:physiopathology*; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012189:Retrospective Studies; D016896:Treatment Outcome