Use of a radiofrequency probe for tenoscopic-guided annular ligament desmotomy

Vascularity evaluation of the equine tarsocrural and proximal intertarsal joint septum, and comparative analysis of two arthroscopic transection techniques

OBJECTIVE

To evaluate vascularity of the synovial membrane covered septum (SMS) separating the tarsocrural (TC) and proximal intertarsal (PIT) joints (Part 1) and compare two methods of transection, electrosurgical or Ferris Smith rongeur (FS rongeur) (Part 2).

STUDY DESIGN

Experimental study.

SAMPLE POPULATION

Part 1, 10 SMS (n = 5 horses). Part 2, six horses (n = 12 tarsi).

METHODS

In part 1, SMS harvested postmortem were each divided into eight regions of interest (ROIs), processed for histology, and immunostained with anti-α-actin antibody for blood vessel identification. Vascular density was calculated for each ROI. Data was compared within and between horses. In part 2, six horses underwent TC arthroscopy. Each limb was randomly assigned to undergo either electrosurgical or FS rongeur SMS transection. SMS transection and total operative time were recorded. Intraoperative hemorrhage was scored. Data was compared between both techniques.

RESULTS

Significant interindividual variations in SMS vascular density were detected (p = .02), but there were no differences among ROIs. No differences in the transection time were detected between electrosurgery (4.83 ± 0.54 min) and FS rongeur (4.33 ± 0.67 min). No differences were found in intraoperative hemorrhage scores between techniques.

CONCLUSION

Vascularity within the SMS varies among horses but not within its regions. Electrosurgical or FS rongeur transection of the medial SMS during tarsocrural arthroscopy is a rapid technique and improves surgical access to the dorsal compartment of the PIT.

Ex vivo evaluation of a percutaneous thread-transecting technique for desmotomy of normal palmar/plantar annular ligaments in horses

OBJECTIVE

To develop and describe a minimally invasive, ultrasound-guided, percutaneous technique for the desmotomy of equine palmar/plantar annular ligaments (PALs) using a transecting thread.

STUDY DESIGN

Ex vivo study.

SAMPLE POPULATION

Twenty-one normal equine distal limb specimens.

METHODS

Under ultrasonographic guidance, a surgical thread was percutaneously placed around the PAL through 2 skin punctures (proximal and distal) using a 18 gauge spinal needle in equine limbs (11 forelimbs, 10 hindlimbs) with normal PALs. The ligament was transected by a back-and-forth motion of the thread until the loop emerged from the proximal skin puncture site. Each specimen was dissected and assessed for completeness of transection and iatrogenic damage under direct visualization. Descriptive statistics were reported.

RESULTS

The PAL was completely transected in 17/21 limbs. The mean duration of the procedure was 16 minutes. Superficial needle puncture or subtle abrasion of the superficial digital flexor tendon was noticed in 4 limbs. No iatrogenic injury to other intrathecal structures was identified. After PAL division, the needle entry and exit points had a mean diameter of 1.2 and 1 mm, respectively.

CONCLUSION

Desmotomy of normal PALs in equine limb specimens was performed effectively using the percutaneous thread-transecting technique with minimal iatrogenic damage to adjacent structures.

CLINICAL SIGNIFICANCE

Information from this study will allow refinement of the technique for use in equine clinical cases either in standing or anesthetized horses.

Arthroscopic removal of osteochondral fragments in the dorsal pouch of the proximal intertarsal joint in 29 horses

OBJECTIVE

To describe the radiographic and surgical findings of horses with osteochondral fragments (OCF) in the proximal intertarsal joint (PIJ) and to detail the technique for arthroscopic fragment retrieval and report outcomes.

STUDY DESIGN

Retrospective case series.

ANIMALS

Twenty-nine horses (32 tarsi) with OCF in the PIJ.

METHODS

Medical records of horses with radiographic evidence of OCF in the PIJ were reviewed. Clinical features, number of fragments, location, arthroscopic appearance, and outcome were recorded. Technical modifications with visual aids specific to this arthroscopic technique are described.

RESULTS

Twenty-seven horses (93%) had radiographic evidence of osteochondritis dissecans lesions in the tarsocrural joint (TCJ). OCF were most commonly located distal to the medial trochlear ridge of the talus. In all cases, fragments were successfully retrieved with a technique based on exposing the fragments after resection of the proximal intertarsal joint capsule (PIJC). Fragments were visible from the TCJ prior resection of the PIJC in 4 of 32 tarsi. A third portal was created to access fragments located distal to the lateral trochlear ridge in 3 of 32 tarsi. Moderate intra-articular bleeding occurred when the PIJC was resected in 3 of 32 tarsi. One horse had postoperative swelling that resolved with conservative medical management. All horses with long-term follow-up available (16/29) started training or returned to their athletic career.

CONCLUSION AND CLINICAL SIGNIFICANCE

The arthroscopic technique based on resection of PIJC was effective in retrieving OCF in the PIJ and was associated with minor complications. The clinical relevance of these fragments in the PIJ remains unknown.