Laparoscopic cryptorchidectomy using a resorbable self-locking loop device in dorsally recumbent horses.

OBJECTIVE: To report the use and feasibility of a self-locking resorbable loop device for cryptorchidectomy. STUDY DESIGN: Clinical prospective study. POPULATION: Twenty horses. METHODS: Horses suspected to have an abdominal testicle/s after admission work-up were enrolled. Horses were anesthetized in dorsal recumbency and a standard laparoscopic technique was performed. The looped device was inserted into the abdomen, glided around the testis/cord and tightened. Then, the spermatic cord was transected prior testis removal. Surgical procedure details and remarks, perioperative complications and total surgical time were recorded. Short- (>3 weeks) and long-term (>6 months) follow-ups were obtained by telephone questionnaire. RESULTS: Median total surgical time was 67 min (range: 43-189 min) and significantly shortened after the first four horses. The loop device was easily glided around 13/20 abdominal testes and required more time and technical skills around larger testes (≥3 years). Excellent intraoperative hemostasis was achieved in 17 horses. Three horses demonstrated mild intraoperative bleeding that required retightening, device replacement or adding a second device, respectively. Three horses developed mild postoperative hemoabdomen identified ultrasonographically and were successfully managed medically. Follow-up revealed no significant complications related to the procedure. One horse was euthanized for colic 4 months after surgery and one died of hemolytic shock 17 months postoperatively. CONCLUSION: This device represents another method to perform equine cryptorchidectomy that requires minimal training and laparoscopic expertise but demands knowledge of the device and application to prevent complications. CLINICAL SIGNIFICANCE: Laparoscopic cryptorchidectomy using this device is an alternative technique for horses <3 years.

Minimally invasive ultrasound-assisted cutting thread tenotomy of the deep digital flexor tendon in horses: An ex vivo study.

OBJECTIVE: To evaluate the feasibility and limitations associated with a minimally invasive ultrasound-assisted cutting thread technique for tenotomy of the deep digital flexor tendon (DDFT) in horses. STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Twenty cadaveric forelimbs. METHODS: Forelimbs were placed on a jig to mimic a standing semiflexed position and the midmetacarpal region was prepared to perform tenotomy of the DDFT using a percutaneous technique with a cutting thread. For that purpose, the thread was placed percutaneously around the DDFT (first dorsally and then palmarly) with the aid of a curved 20 gauge spinal needle. Tendon palpation/manipulation and ultrasonographic assessment assisted thread placement. Procedure time and skin puncture size were recorded. Limbs were then dissected to evaluate the degree of DDFT transection and the presence of any iatrogenic lesions. RESULTS: The DDFT was completely transected in all cases. Minor lesions of the superficial digital flexor tendon were found in 11/20 limbs and considered clinically irrelevant. However, the neurovascular bundle was damaged in 6/20 limbs (four limbs had nerve damage and two limbs had a nerve and either a palmar artery or vein damaged). The skin puncture hole sizes ranged from undetectable to 5 mm long. The average duration of the procedure was 7 min and 38 s (range: 4 min 56 s to 10 min 19 s). CONCLUSION: A DDFT tenotomy can be performed reliably with a percutaneous cutting thread technique. However, refinement of the technique is required to minimize iatrogenic damage. CLINICAL SIGNIFICANCE: The reported technique allows a DDFT tenotomy to be performed in a minimally invasive manner and has the potential to be clinically applicable.

Minimally invasive removal of obstructive ureteral stones by intracorporeal lithotripsy in horses: 3 patients.

Three client-owned horses diagnosed with obstructive ureteral stones were referred and treated in a minimally invasive manner by retrograde ureteroscopy in conjunction with electrohydraulic lithotripsy (EHL) or laser Holmium:YAG lithotripsy (HYL). For all 3 horses, additional tests revealed variable degrees of azotemia and ureteral obstruction. Ultrasound examination (2 horses) revealed a loss of cortico-medullary distinction consistent with a chronic nephropathy. Ultrasound-guided biopsy of the right kidney in 1 horse revealed moderate glomerulosclerosis and lymphoplasmacytic nephritis. A standing anesthesia with a coccygeal epidural was done for each horse. A perineal urethrotomy was performed in 2 horses before the urethrocystoscopy. One horse was treated with Holmium:YAG laser lithotripsy and 2 others were treated using a electrohydraulic lithotripsy probe. Each procedure was successful. The ureteroscopy was successfully performed and visualization was excellent. Fragmentation of stones seemed easier with the electrohydraulic lithotripsy probe. No complications, pain, or signs of discomfort after the procedure were noticed. All 3 horses were discharged from the hospital. Key clinical message: Obstructive ureteral stones in horses can be successfully treated in a minimally invasive manner by retrograde ureteroscopy accompanied by lithotripsy. This technique is safe, not painful and did not require general anesthesia. Electrohydraulic lithotripsy appeared superior for stone fragmentation.

Exérèse minimalement invasive de calculs urétéraux obstructifs par lithotritie intracorporelle chez le cheval : trois patients. Trois chevaux appartenant à des clients diagnostiqués avec des calculs urétéraux obstructifs ont été référés et traités de manière peu invasive par urétéroscopie rétrograde en conjonction avec une lithotripsie électrohydraulique (EHL) ou une lithotripsie au laser Holmium:YAG (HYL). Pour les trois chevaux, des tests supplémentaires ont révélé des degrés variables d'azotémie et d'obstruction urétérale. L'échographie (deux chevaux) a révélé une perte de distinction cortico-médullaire compatible avec une néphropathie chronique. La biopsie échoguidée du rein droit chez un cheval a révélé une glomérulosclérose modérée et une néphrite lymphoplasmocytaire. Une anesthésie debout avec une péridurale coccygienne était effectuée pour chaque cheval. Une urétrotomie périnéale a été réalisée chez deux chevaux avant l'urétrocystoscopie. Un cheval a été traité par lithotripsie au laser Holmium:YAG et deux autres ont été traités à l'aide d'une sonde de lithotripsie électrohydraulique. Chaque procédure a réussi. L'urétéroscopie a été réalisée avec succès et la visualisation était excellente. La fragmentation des calculs semblait plus facile avec la sonde de lithotripsie électrohydraulique. Aucune complication, douleur ou signe d'inconfort après la procédure n'a été remarqué. Les trois chevaux ont obtenu leur congé de l'hôpital.Message clinique clé :Les calculs urétéraux obstructifs chez les chevaux peuvent être traités avec succès de manière peu invasive par urétéroscopie rétrograde accompagnée de lithotripsie. Cette technique est sûre, non douloureuse et ne nécessite pas d'anesthésie générale. La lithotritie électrohydraulique est apparue supérieure pour la fragmentation des calculs.(Traduit par Dr Serge Messier).

Standing surgery among equine board certified surgeons: Survey regarding current use and trends.

BACKGROUND: Publications about equine standing surgery are flourishing, however, information regarding its use and prevalence among surgeons is still limited. OBJECTIVES: To determine the current use and recent trends for equine standing surgery among board certified surgeons and to identify the main reasons and limitations for performing a procedure standing. STUDY DESIGN: Cross-sectional survey. METHODS: A 139-item questionnaire was sent by email to 733 large animal surgery Diplomates (ACVS and ECVS) from November 2020 to February 2021. The survey collected demographic information and general data regarding standing surgery before being divided into seven identical sections for each body system, involving 36 standing procedures. RESULTS: The survey response rate was 29.7% (218/733). Most respondents (58.9%, 126/214) had performed standing surgery for <10 years regardless of length of time they were board certified (48.2% board certified <10 years and 51.8% >10 years). Most respondents (range: 50.0%-92.9%, mean 69.5%) changed from performing 14/36 surgeries under general anaesthesia (GA) to standing within the previous 10 years and had always performed 8/36 surgeries standing (51.6%-73.9%, mean 61.4%) regardless of board certification time. Surgeons board certified <10 years ago performed more often 3/36 listed procedures standing than those board certified >10 years ago (p < 0.05). Avoiding GA (179/218) and/or reducing procedure cost (111/218) were the two main reasons to perform standing surgeries whereas the horse's behaviour (183/218) and/or the patient size/age (94/218) were the two main limiting factors. MAIN LIMITATIONS: Low response rate. Results biased towards the opinion of a subgroup of surgeons, those performing standing surgery. Some standing procedures were not included in the survey. CONCLUSIONS: The use of standing surgery is well established among board certified surgeons and progressively increasing, especially in the last 10 years and among recent Diplomates. With increased training and awareness, more Diplomates may be encouraged towards performing standing surgeries.

Use of Clinical Audits to Evaluate Timing of Preoperative Antimicrobials in Equine Surgery at a Veterinary Teaching Hospital.

Based on human surgical guidelines, intravenous antimicrobials are recommended to be administered within 60 min of surgical incision. Achieving this target in horses is reportedly challenging and influenced by hospital policies. The objectives of this study were to evaluate and improve: (1) the timing of antimicrobial administration to surgical incision (tAB-INC), (2) contributions of anesthesia pre-induction (tPRI) and surgical preparation (tPREP) periods to tAB-INC, and the (3) completeness of antimicrobial recording. Two clinical audits were conducted before and after the policy changes (patient preparation and anesthesia record keeping). tPRI, tPREP, and tAB-INC were calculated and compared for elective arthroscopies and emergency laparotomies within and between the audits. The percentage of procedures with a tAB-INC <60 min was calculated. Antimicrobial recording was classified as complete or incomplete. A median tAB-INC <60 min was achieved in laparotomies (audit 1; 45 min, audit 2; 53 min) with a shorter tPREP than arthroscopies (p < 0.0001, both audits). The percentage of procedures with tAB-INC <60 min, tAB-INC, tPRI, and tPREP durations did not improve between the audits. There was a positive correlation between the number of operated joints and tPREP (audit 1, p <0.001, r = 0.77; audit 2, p < 0.001, r = 0.59). Between audits, antimicrobial recording significantly improved for elective arthroscopies (82-97%, p = 0.008) but not emergency laparotomies (76-88%, p = 0.2). Clinical audits successfully quantified the impact of introduced changes and their adherence to antimicrobial prophylaxis guidelines. Antimicrobial recording was improved but further policy changes are required to achieve a tAB-INC <60 min for arthroscopies.

Diagnostic needle arthroscopy of the scapulohumeral joint in standing sedated horses.

OBJECTIVE: To describe the technique to perform diagnostic standing scapulohumeral joint needle arthroscopy with a 1.2-mm-diameter arthroscope in horses. STUDY DESIGN: Experimental study. ANIMALS: Eight thoracic limbs in phase 1 and six horses in phase 2. METHODS: In phase 1, the feasibility of the technique was evaluated by using a craniolateral arthroscopic approach. An evaluation of the visible structures of the scapulohumeral joint was performed with both a needle arthroscope and a 4-mm-diameter arthroscope. In phase 2, the technique was performed in six healthy sedated horses to validate the technique in live animals and to report any complications or limitations. RESULTS: In phase 1, joint evaluation was similar between arthroscopes and allowed complete evaluation of approximately the lateral half of the humeral head and the lateral glenoid rim. In phase 2, all joints were successfully accessed, and fluid extravasation was mild. Arthroscopic visualization was complete for the centrolateral aspect of the joint in all horses and either complete (3/6) or partial (3/6) for the craniolateral and caudolateral structures, respectively. The procedure was rapidly performed and well tolerated, and no postoperative complications occurred. CONCLUSION: The described technique was simple and allowed direct inspection of the scapulohumeral joint. Nonetheless, the standing nature of the technique prevents evaluation of the medial aspect of the humeral head and most of the glenoid cavity. CLINICAL SIGNIFICANCE: Needle arthroscopy of the scapulohumeral joint is feasible in horses and offers a diagnostic technique that may improve the surgeon's diagnostic ability for certain shoulder pathologies.

Needle arthroscopy of the radiocarpal and middle carpal joints in standing sedated horses.

OBJECTIVE: To develop a technique for standing diagnostic needle arthroscopy of the radiocarpal and middle carpal joints in standing sedated horses. STUDY DESIGN: Experimental study. ANIMALS: Six cadaveric forelimbs (phase 1) and six healthy horses (phase 2). METHODS: In phase 1, six cadaveric forelimbs were used to assess needle arthroscopic evaluation of both joints. Six healthy horses were subsequently enrolled in phase 2 to validate the procedure in live animals. The joint was maintained in flexion with a custom-made splint and base. RESULTS: In phase 1, needle arthroscopy allowed thorough evaluation of the dorsal and palmar recesses of both joints with traditional arthroscopic portals. In phase 2, joint evaluation was also thorough but only dorsal approaches were performed. All horses underwent radiocarpal joint arthroscopy, whereas the middle carpal joint was evaluated in only three of six horses because of limb movement. The technique was quickly performed and well tolerated by all horses. Complications included moderate movement, mild iatrogenic cartilage damage, and mild hemarthrosis. CONCLUSION: Standing needle arthroscopy allowed thorough evaluation of the dorsal aspect of both joints, although only three of six middle carpal joints were assessed because of movement limitations. CLINICAL SIGNIFICANCE: The proposed technique offers an alternative diagnostic tool for radiographically silent intra-articular lesions of the carpus while initially avoiding the cost and risks associated with general anesthesia. Arthroscopy of a single joint is recommended to minimize risks associated with movement during the procedure.

Diagnostic tenoscopy of the carpal sheath with a needle arthroscope in standing sedated horses.

OBJECTIVE: To investigate the use of a needle arthroscope for diagnostic tenoscopy of the carpal sheath in standing horses. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Six forelimbs for the cadaveric part of the study and six horses for the in vivo part of the study. METHODS: Six cadaveric limbs were used to perform carpal sheath tenoscopy with a 1.2-mm-diameter needle arthroscope (65 and 100 mm long), followed by tenoscopy with a 4-mm arthroscope through a standard proximolateral approach. Then, unilateral standing carpal sheath tenoscopy was performed in six healthy sedated horses with a 65-mm-long needle arthroscope. Limbs were maintained in flexion during the procedure by using a custom-made splint and base. Degree of tenoscopic evaluation, safety, horse tolerance, and complications were recorded. RESULTS: Visibility at the most distal aspect of the sheath was absent for the needle arthroscopes vs a standard arthroscope. The maneuverability with a 65-mm needle arthroscope was excellent and allowed exhaustive visualization of the proximal region of the carpal sheath in cadaveric limbs and standing horses (six of six). However, visualization of the intertendinous recess was partial in most horses (four of six) vs cadavers (complete in six of six) because of remaining flexor tendon tension in standing horses. No major complications were encountered. CONCLUSION: Standing carpal sheath tenoscopy allowed a safe and thorough evaluation of most structures in the proximal region of the sheath and offers an alternative diagnostic technique. CLINICAL SIGNIFICANCE: Horses with unrewarding results after traditional imaging or that require an accurate diagnosis before treatment may benefit from this alternative procedure.

Diagnostic needle arthroscopy of the tarsocrural joint in standing sedated horses.

OBJECTIVE: To develop and assess a needle arthroscopic technique to diagnose conditions of the tarsocrural joint (TCj) in standing sedated horses. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Six cadaveric hind limbs (phase 1) and six healthy horses (Phase 2). METHODS: In phase 1, each TCj was examined with a 1.2-mm-needle arthroscope. Suitability of the needle arthroscope and degree of joint visualization with traditional arthroscopic approaches were assessed. In phase 2, the feasibility of the procedure was assessed in six standing healthy horses. A custom-made splint and base were developed to maintain joint flexion during the procedure. RESULTS: Thorough evaluation of the dorsal intra-articular structures of the TCj via dorsomedial and dorsolateral approaches was possible in both phases. The procedure was feasible, quickly performed, and well tolerated by all horses. Complications consisted of moderate movement (2/6 horses) and hemarthrosis (3/6 horses). CONCLUSION: Diagnostic standing needle arthroscopy of the TCj allowed thorough evaluation of the dorsal aspect of the joint while avoiding the cost and risks associated with general anesthesia. Inadvertent puncture of the dorsomedial vasculature with the cannula and obturator led to significant hemarthrosis. CLINICAL IMPACT: Needle arthroscopy of the TCj offers an alternative diagnostic tool when traditional imaging techniques (radiography and ultrasonography) are unrewarding or nondiagnostic. The technique is conceived mainly for diagnostic purposes, but its use during short interventions warrants investigation.

Standing Needle Arthroscopy of the Metacarpophalangeal and Metatarsophalangeal Joint for Removal of Dorsal Osteochondral Fragmentation in 21 Horses.

OBJECTIVE: The aim of this study was to report the technique, experience and outcome of standing arthroscopic removal of dorsal osteochondral fragmentation of the metacarpophalangeal and metatarsophalangeal joint using a 1.2-mm needle arthroscope. STUDY DESIGN: This was a prospective clinical study. MATERIALS AND METHODS: All horses referred for standing arthroscopic removal of dorsoproximal first phalanx fragments or fragments embedded in the distal aspect of the synovial plica were included. Relevant information from the cases was recorded. Follow-up was obtained by a telephone questionnaire. RESULTS: Twenty-one horses with a mean age of 4.5 years old were included. Osteochondral fragments removed were from the proximal margin of first phalanx in 18 horses (24 joints), in the synovial plica in 2 horses (2 joints) or free-floating fragment in 1 horse (1 joint). Fifteen out of twenty-one horses were unilaterally affected and 6/21 bilaterally. Fifteen out of twenty-seven affected joints were forelimbs and 12/27 hindlimbs. All articular structures within the dorsal recess of the joint were visible. The arthroscope was deemed easy to use and manoeuvre. Only minor complications occurred during the procedure. Surgery time was 15 to 20 minutes for most patients. CONCLUSIONS: All fragments were successfully removed and needle arthroscopy allowed a thorough evaluation of the dorsal aspect of the joint. The technique offers an alternative for standing fetlock arthroscopy for surgeons concerned about equipment damage or portability.

Concurrent or sequential tibial subchondral cystic lesions in 4 horses with medial femoral condyle subchondral cystic lesions.

CASE DESCRIPTION 4 horses were examined because of signs of chronic hind limb lameness. CLINICAL FINDINGS 3 horses had a history of lameness for > 6 months; specific duration was unknown for 1 horse. On initial evaluation, grade 3 to 4 (on a scale from 1 to 5) hind limb lameness was present in all 4 horses. Radiography of the stifle joint of the affected limb revealed medial femoral condyle subchondral lucencies or subchondral cystic lesions (SCLs) in all 4 horses, medial femorotibial osteoarthritis in 3 horses, and medial tibial condyle SCLs in 3 horses. TREATMENT AND OUTCOME 2 horses were treated medically (stall rest and oral NSAID administration), and 2 horses were treated surgically by means of medial femoral transcondylar lag screw placement through the medial femoral condyle SCLs. The 2 horses treated medically did not improve and were euthanized. Necropsy confirmed the presence of medial femoral condyle and medial tibial condyle SCLs. Surgical treatment did not resolve the lameness in 1 horse with SCLs in the medial tibial condyle and medial femoral condyle, and euthanasia was performed 150 days after surgery. In the second horse, a medial tibial condyle SCL was evident on radiographs obtained 3 months after surgery; however, this was not addressed surgically, and signs of lameness resolved 11 months after surgery. CLINICAL RELEVANCE Results of this small case series suggested that SCLs in the medial tibial condyle can occur in association with SCLs of the medial femoral condyle, with a poor prognosis for return to athletic function in affected horses. Further investigation is indicated.

Comminuted fracture of the accessory carpal bone removed via an arthroscopic-assisted arthrotomy.

A 16-year-old American paint horse gelding was presented for evaluation of a left forelimb lameness grade III/V. Radiographs and computed tomography revealed a comminuted fracture of the accessory carpal bone involving the entire articulation with the distal radius and the proximal aspect of the articulation with the ulnar carpal bone. Multiple fragments were present in the palmar pouch of the antebrachiocarpal joint. An arthroscopic-assisted open approach was necessary to remove all fractured fragments. Subsequently the horse was re-admitted for lameness and was treated successfully with antibiotics and long-term supportive bandaging.

Fracture comminutive de l'os du carpe accessoire enlevé à l'aide d'une arthrotomie assistée par arthroscopie. Un cheval American Paint Horse âgé de 16 ans a été présenté pour l'évaluation d'une boiterie de la jambe avant gauche de grade III/V. Les radiographies et la tomodensitométrie ont révélé une fracture comminutive de l'os du carpe accessoire touchant toute l'articulation avec le radius distal et l'aspect proximal de l'articulation avec l'os du carpe cubital. Des fragments multiples étaient présents dans la poche palmaire de l'articulation antébrachio-carpienne. Une approche ouverte assistée par arthroscopie a été nécessaire pour retirer tous les fragments fracturés. Le cheval a ensuite été réadmis pour boiterie et a été traité avec succès à l'aide d'antibiotiques et de pansements de soutien à long terme.(Traduit par Isabelle Vallières).

Ex vivo equine medial tibial plateau contact pressure with an intact medial femoral condyle, with a medial femoral condylar defect, and after placement of a transcondylar screw through the condylar defect.

OBJECTIVE: To determine ex vivo contact data on the equine medial tibial plateau loaded by an intact medial femoral condyle (MFC), by an MFC with an osteochondral defect, and with a screw inserted in lag fashion through the MFC defect. STUDY DESIGN: Ex vivo experiment. ANIMALS: Stifles (n = 6). Horses (n = 4). METHODS: Stifle joints were axially loaded to 1800 N at 155°, 145°, and 130°, under 3 conditions: Intact, MFC with a 15 mm circular osteochondral defect, and with a transcondylar screw inserted in lag fashion through the defect. An electronic pressure sensor (Tekscan®) on the medial tibial plateau recorded contact area, force, peak pressure, and contact maps. Stress load (N/cm(2) ) was calculated for the entire medial plateau and in 3 sub-regions; cranial, caudal, and central. Significance was set at P ≤ .05. RESULTS: Flexion increased force, contact area, and stress load for all conditions. An MFC defect significantly reduced force at both flexion angles and contact area at 145°. The transcondylar screw returned force to intact values at 130° and reduced contact area in extension. Intact MFC contact maps revealed pressure peaks on the central cartilage at all angles and contact pressure and area expansion and caudal movement with flexion. Contact maps with an MFC defect amplified the caudal and abaxial pressure movement during flexion, and the screw did not further change them. CONCLUSIONS: Stifle flexion increases force, contact area, and stress load on the medial tibial plateau and is most pronounced caudally. An MFC defect alters load on the medial tibial plateau, and a transcondylar screw may reverse some of those changes.

Minimally invasive repair of a calcaneus fracture in a Standardbred foal.

CASE DESCRIPTION: A 4-month-old Standardbred colt was examined because of a fractured right calcaneus of 8 days' duration with increased distraction of the fracture fragment evident on sequential radiographs. CLINICAL FINDINGS: The foal was severely lame with diffuse periarticular tarsal swelling. Radiographically, a complete, displaced long oblique fracture of the right calcaneal body was evident. Because the fracture gap was increasing with time and lameness remained severe, despite medical management, surgical repair was recommended. TREATMENT AND OUTCOME: The foal was anesthetized, and minimally invasive fracture reduction and internal fixation were achieved by use of two 4.5-mm cortical screws placed in lag fashion via stab incisions over the lateral aspect of the calcaneus. External coaptation with a Robert-Jones bandage only was used after surgery. The foal recovered well and the fracture healed appropriately, but at 8 weeks following surgery, tenosynovitis of the tarsal sheath had developed. This was attributed to the tip of the distal screw encroaching on the sheath. The screw was removed under anesthesia and the tarsal sheath drained. The tenosynovitis resolved with rest and bandaging. Fourteen months after surgery, the colt was free of lameness. CLINICAL RELEVANCE: Findings suggested that a minimally invasive internal fixation technique for treatment of a calcaneus fracture in horses may be successful and may be associated with decreased morbidity, compared with the use of open reduction and plate fixation.