title: Frequency of Penetration of the Digital Flexor Tendon Sheath and Distal Interphalangeal Joint Using a Direct Endoscopic Approach to the Navicular Bursa in Horses.
abstract: OBJECTIVE
  To evaluate the frequency of inadvertent penetration of the digital flexor tendon sheath (DFTS) and/or distal interphalangeal joint (DIPJ) when using a direct endoscopic approach to the navicular bursa, and to evaluate an alternate direct approach to the navicular bursa.
  
  
  METHODS
  Cadaveric study.
  
  
  METHODS
  Equine cadaver limbs (n = 40 for direct; n = 12 for alternate approach).
  
  
  METHODS
  Four surgeons performed the direct endoscopic approach to the navicular bursa on 10 limbs each. Frequencies of inadvertent synovial penetration and iatrogenic damage were compared between surgeons. Use of an alternate direct approach, adopting a straight parasagittal trajectory, was evaluated by 2 surgeons.
  
  
  RESULTS
  Inadvertent synovial penetration occurred in 45% of limbs (DFTS 37.5%; DIPJ 17.5%; and both structures 10%). Successful bursa entry was achieved on the first attempt in 45% of limbs. Significant variation in frequency of inadvertent synovial penetration was observed between surgeons (range 10-80%). Inadvertent synovial penetration did not occur when using the alternate direct technique. Iatrogenic damage to navicular bone fibrocartilage and/or deep digital flexor tendon occurred in 55% of limbs using the direct endoscopic approach and in 0% of limbs using the alternate direct approach.
  
  
  CONCLUSIONS
  Because of the considerable risk of inadvertent penetration of the DFTS and/or the DIPJ when making a direct endoscopic approach to the navicular bursa, it is advisable to investigate for inadvertent penetration when treating navicular bursa sepsis using a direct approach. The alternate direct technique may reduce the risk of inadvertent penetration; however, the view within the bursa may be restricted.
authors.affiliation: The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Justine
authors.initials: J
authors.lastname: Kane-Smyth
authors.affiliation: The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Sarah Elizabeth
authors.initials: SE
authors.lastname: Taylor
authors.affiliation: The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Eugenio Cillán
authors.initials: EC
authors.lastname: García
authors.affiliation: The Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Richard J M
authors.initials: RJ
authors.lastname: Reardon
mesh_terms: D000818:Animals; D001182:Arthroscopy / Q000009:adverse effects / Q000662:veterinary*; D002061:Bursa, Synovial / Q000293:injuries* / Q000601:surgery; D002102:Cadaver; D005260:Female; D005552:Forelimb / Q000601:surgery; D006614:Hindlimb / Q000601:surgery; D006736:Horses; D007049:Iatrogenic Disease / Q000662:veterinary*; D008297:Male; D013639:Tarsal Bones / Q000601:surgery*; D013708:Tendon Injuries / Q000209:etiology / Q000662:veterinary*