The use of computed tomography to assist orthopaedic surgery in 86 horses (2002-2010)

Abstract

Summary Imaging‐assisted orthopaedic surgery is becoming part of routine orthopaedic practice in horses and several techniques have been reported. However, there are no published reports describing the use of intraoperative computed tomography (CT) for surgical guidance and immediate post operative control in the horse. This use of CT in equine orthopaedics is currently limited because of the logistic problems associated with availability of CT scans in surgical theatres as well as concerns over radiation safety. The aim of this report was retrospectively to report CT assisted orthopaedic surgical cases in our practice through identifying the types of surgery where it was used, to list the technical problems that were encountered, to describe solutions to these, and to discuss the applications of the technique. All surgical procedures were performed with the assistance of a peripheral quantitative computed tomography (pQCT) scanner. CT assisted orthopaedic surgery in 86 patients during the study period. Reasons for CT included: 1) use of CT at the beginning of the surgical procedure to document the lesion and identify surgical landmarks (n = 75); 2) pre, intra‐ and post operative use of CT in comminuted fractures of the middle or proximal phalanx to guide and control internal fixation (n = 7); and 3) post operative use of CT to monitor the results of the surgical procedure (n = 4). Proper planning in both the draping steps and the use of polyvinyl splints to stabilise the limb allowed for movements of the gantry around the limb. The time required to obtain one slice was not dissimilar to the time that is necessary to take and process a single digital radiograph. The radiation dose with the pQCT described here is <0.5 µSv and its acquisition time should be balanced against radiation risks of conventional CT systems.

Standing MRI for surgical planning of equine fracture repair

“…Moreover, such timing would preclude the informed consent from the owner prior to general anesthesia provided by the sMRI. In contrast to CT, MRI cannot be used intraoperatively to confirm adequate positioning of screws. Moreover, metallic implants preclude postoperative sMRI.…”

Interventional computer tomography – a new dimension in horse medicine – Part 1: CT assisted drilling and filling of subchondral cystic lesions in the horse

“…Nur eine Arbeit beschreibt die intraoperative Nutzung eines Computertomographen in vivo beim Pferd. Perrin et al (2011) (Fürst et al 1997, von Rechenberg et al 1998. SKZ kommen sowohl mit als auch ohne Gelenkbeteiligung vor (Petterson und Reiland 1969).…”

Clinical Use of Computed Tomography and Surface Markers to Assist Internal Fixation Within the Equine Hoof

“…While conceptually simple, internal fixation of the DP and DSB remains challenging because of deep encapsulation by the hoof wall and extremely narrow anatomic margin for errors . These repairs have been accomplished with 2D imaging techniques but recent reports have documented the superiority and simplicity of 3D imaging for preoperative planning, intraoperative control, and postoperative evaluation …”

“…Preoperative and intraoperative planning generally consists of image series taken with radiopaque markers attached to the hoof wall . This can be accomplished before general anesthesia with specially modified equipment .…”

“…Intraoperative 3D imaging allows greater control of drilling distance and direction than 2D imaging . It has proven to yield more accurate implant placement in DP fractures in vitro .…”