Desmotomy of the Accessory Ligament of the Deep Digital Flexor Tendon in Horses: An Update

Desmotomy of the accessory ligament of the deep digital flexor tendon is advocated to allow for lengthening of the deep digital flexor musculotendinous unit and axial realignment of the bones of the digit. This procedure has several indications. It can be performed using either the open or the minimally invasive surgical approach. This article describes both surgical approaches. Corrective shoeing before surgery contributes to success in both surgical approaches. The cosmetic results obtained after the minimally invasive procedure are much better as compared with those after the open surgical procedure. The minimally invasive approach compares favorably with results reported after using an open surgical approach and offers the advantages of minimally invasive surgery including reduced incision length, reduced morbidity, and improved cosmetic outcome. The minimally invasive approach may be also performed on the standing sedated horse.     

Ultrasound-Guided Transection of the Accessory Ligament of the Deep Digital Flexor Muscle (Distal Check Ligament Desmotomy) in Horses

Transection of the accessory ligament of the deep digital flexor muscle (distal check ligament desmotomy) was completed in 44 horses using an ultrasound-guided technique. The technique used real-time ultrasound with a 7.5 MHz transducer to observe the dissection and isolation of the check ligament through a 1 to 1.5 cm incision and to check for complete transection of the check ligament. The technique was effective in correcting flexural deformity of the distal inter-phalangeal joint and the metacarpophalangeal joint in all but three horses. Check ligament desmotomy at a young age (median, 6 months) resulted in more horses with normal foot conformation than when surgery was completed at an older age (median, 12 months). Age at surgery had no effect on subsequent appearance of the surgical site. Based on the authors experience this technique reduced immediate postoperative wound morbidity.     

Medial patellar ligament splitting for the treatment of upward fixation of the patella in 7 equids

OBJECTIVE: To describe a surgical technique for splitting the proximal third of the medial patellar ligament (MPL) in horses and ponies with upward fixation of the patella (UFP), and to report outcome. STUDY DESIGN: Prospective clinical study. SAMPLE POPULATION: Four horses and 3 Shetland ponies. METHODS: With ultrasound guidance, the proximal third of the MPL was split by percutaneous use of a no. 15 scalpel blade. The rationale for this surgical procedure was to induce a localized desmitis with subsequent ligament thickening. No anti-inflammatory drugs were administered, and horses and ponies were exercised the day after surgery. Clinical, radiographic and ultrasonographic follow-up evaluation was obtained. RESULTS: No short-term or long-term complications were observed, and no patients had clinical signs of UFP after surgery. This clinical effect was attributed to a 2- to 3-fold increase in size of the proximal part the MPL from an induced localized desmitis. CONCLUSIONS-Percutaneous splitting of the proximal third of the MPL resolved UFP in equids. CLINICAL RELEVANCE: Splitting of the proximal third of the MPL is effective for treatment of UFP and allows rapid return to normal activity.     

Pilot study of the ultrasonographic examination of the intact and transected medial glenohumeral ligament in dogs

Medial glenohumeral ligament injury is commonly reported during medial shoulder joint instability in dogs. Arthroscopy is considered the gold standard procedure, but it is invasive and requires distension of the joint. Ultrasonographic examination of the medial glenohumeral ligament has been studied as a possible, less invasive alternative to arthroscopy however it has not been considered a useful method of assessment due to the interference of the probe with the pectoral muscles. The aims of this prospective analytical randomized pilot study were to develop a standardized ultrasound protocol for visualizing the canine medial glenohumeral ligament and to compare goniometry and ultrasound findings in cadaver dogs with versus without transection of the medial glenohumeral ligament. Nine adult Beagle cadavers (18 shoulders) were used. The first six shoulders were used in a preliminary study to describe an ultrasound technique to identify the medial glenohumeral ligament. Arthroscopy was performed on the remaining 12 shoulders, with six randomly selected medial glenohumeral ligaments from these shoulders, transected during the procedure. Ultrasound examination was performed after each arthroscopic procedure by an ultrasonographer blinded to the patient group. Four medial glenohumeral ligaments (67%) were correctly identified during the preliminary study. Ultrasonographic examination failed to diagnose the transection of all six medial glenohumeral ligaments in the second part of the study. No difference was observed in the ligament thickness between the dogs with and without a transected medial glenohumeral ligament. Dogs with a transected medial glenohumeral ligament had a wider articular space compared to dogs without a transected ligament (P < 0.001), and an articular space wider than 8.2 mm was discriminatory of a transected medial glenohumeral ligament in all the shoulders. In conclusion, the medial glenohumeral ligament could be identified with a medial ultrasonographic approach of the shoulder and a wider articular space can be a sign of a medial shoulder joint instability. Further studies are needed to confirm these preliminary findings in living dogs, with and without shoulder instability.     

Tibial wedge ostectomy: complications of 300 surgical procedures

Background   Tibial wedge ostectomy (TWO) is a surgical procedure that aims to give functional stability during weight-bearing in a hindlimb with cranial cruciate ligament deficiency, by reducing the slope of the tibial plateau angle.
Procedure   Advantages of the TWO surgery are that it does not require dedicated equipment and can be performed in young dogs prior to closure of the physis. However, it is a technically demanding procedure and the potential for complications is high.
Results   In this retrospective review of 249 dogs that had unilateral and 51 that had bilateral TWO surgery, the overall complication rate was 31.7% (95/300) and the rate of revision surgery was considerable (37 cases or 12.33%).
Conclusions   The most important clinical complications were postoperative medial meniscal tears, tibial fractures and implant failures, necessitating repeat surgery.     

Arthroscopy of the Coxofemoral Joint of Foals

An arthroscopic procedure for examination of the coxofemoral joint was developed in nine foals (four cadavers, five anesthetized) to determine if access was sufficient for evaluation and surgical treatment of intra-articular lesions. The joint was distended and the arthroscope inserted through the notch (incisura trochanterica) between the cranial and caudal parts of the greater trochanter. This portal allowed examination of the cranial, lateral, and caudal aspects of the joint. Mechanical distraction of the joint through an instrument portal located 2 to 4 cm cranial and 1 to 2 cm ventral to the arthroscope portal allowed examination of the ligament of the head of the femur, the femoral head, and articular and nonarticular surfaces of the acetabulum. Adduction and rotation of the limb improved visualization of the craniomedial and caudomedial portions of the femoral head. Traction applied to the distal limb allowed visualization of the same structures that were observed when mechanical distraction was used. Traction also created space for placement of surgical instruments into the joint through the instrument portal. Access to most regions of the joint was adequate, but access to the caudal and medial aspects of the joint was limited. Three foals were killed while they were anesthetized, and their coxofemoral joints were dissected. Two foals were allowed to recover from anesthesia and were observed for 30 days after surgery. One foal was mildly lame for 2 days after surgery. The other foal was not lame after surgery. The incisions healed, and the coxofemoral joints were radiographically normal by postoperative day 30.     

Complications of tibial plateau levelling osteotomy in dogs

The tibial plateau levelling osteotomy (TPLO) is one of the most common surgical procedures used to treat cranial cruciate ligament disease in dogs. Complications occurring during or after TPLO can range in severity from swelling and bruising to fracture and osteomyelitis. Ten to 34% of TPLO surgical procedures are reported to experience a complication and approximately two to four percent require revision surgery to address a complication. Although the risk factors for many complications have not been fully assessed, the best available evidence suggests that complications of TPLO can be reduced with increased surgeon experience, careful surgical planning, and accurate execution of the surgical procedure. Identification of known or suspected risk factors and intra-operative technical errors allow subsequent action to be taken that is aimed at decreasing postoperative morbidity. There is a need for prospective studies with consistent data reporting in order to fully reveal the incidence risk factors for complications associated with TPLO.     

Intra-articular Graftpasser

The over-the-top placement of prosthetic materials for repair of the cranial cruciate ligament in dogs necessitates much tissue dissection and trauma. Instruments often are stressed beyond their limits, resulting in damage to the instrument. Therefore, an instrument was designed for easier passing of the graft. This graftpasser conforms to the anatomy of the caudal surface of the lateral condyle of the stifle, and facilitates rapid positioning of the graft in close contact with the bone. The instrument was successfully used for this purpose in several surgical cases.     

Desmotomy of the accessory ligament of the superficial digital flexor tendon in the horse with use of a tenoscopic approach to the carpal sheath

Objective— To describe a tenoscopic approach to the carpal sheath for desmotomy of the accessory ligament of the superficial digital flexor tendon. Study Design— The surgical procedure was developed with use of normal forelimbs from equine cadavers and experimental horses. Animals or Sample Population— Twelve equine cadaveric forelimbs, 4 forelimbs from 2 horses anesthetized for terminal surgical laboratories, and 10 forelimbs from five experimental horses were used. Methods— The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal was made approximately 2 cm proximal to the distal radial physis for arthroscope insertion. An instrument portal was made approximately 0.2 cm proximal to the distal radial physis. After flexion of the limb to 90°, the accessory ligament of the superficial digital flexor tendon was palpated and desmotomy was performed. Cadaveric limbs were dissected to confirm complete desmotomy. Experimental horses were monitored for short- (perioperative) and long- (4 weeks) term postoperative complications. Results— A tenoscopic approach to the carpal sheath provided adequate surgical access to the accessory ligament of the superficial digital flexor tendon for desmotomy. Most of the accessory ligament of the superficial digital flexor tendon could be easily seen within the sheath, except for the proximal 2 cm that could be readily palpated and subsequently transected. Important technical considerations were location of the arthroscope portal, adequate sheath distention, limb flexion to 90°, and desmotomy location. It was beneficial, but apparently not essential, to avoid the proximal perforating vessel. Postoperatively, some horses had swelling but were not lame and had normal range of motion of the carpus. Conclusions— Desmotomy of the accessory ligament of the superficial digital flexor tendon could be performed by using a lateral tenoscopic approach to the carpal sheath. Clinical Relevance— Desmotomy of the accessory ligament of the superficial digital flexor tendon by using a tenoscopic approach to the carpal sheath is an alternative technique to the medial incisional approach.     

Evaluation of a tenoscopic approach for desmotomy of the accessory ligament of the deep digital flexor tendon in horses

Objective: To develop a tenoscopic approach for desmotomy of the accessory ligament of the deep digital flexor tendon (AL‐DDFT) in horses. Study Design: Experimental. Animals: Cadaveric forelimbs (n=10) and 4 forelimbs from 2 horses anesthetized for terminal teaching procedures, and 12 forelimbs of 6 experimental horses. Methods: Saline distention of the carpal flexor sheath facilitated insertion of an arthroscope into the distal medial aspect of the sheath between the AL‐DDFT and deep digital flexor tendon (DDFT). Location of an instrument portal on the lateral aspect of the metacarpus was identified with a needle. The lateral aspect of the AL‐DDFT was transected and the arthroscope and instrument were switched to transect the remaining fibers on the medial aspect. Cadaveric specimens were dissected for evaluation. Experimental horses were monitored for 30 days postoperatively. Results: Minor complications including incomplete division of the AL‐DDFT and shallow incision into the suspensory ligament were observed in some cadaver specimens. The AL‐DDFT was completely transected in all experimental horses with no suspensory ligament damage. Mean±SD surgical time (incision to skin closure) was 28.3±11.8 minutes. On ultrasonographic examination, transection of the AL‐DDFT was complete in all experimental horses. Minor DDFT fiber disruption was noted in 1 limb during ultrasound examination at day 30. Conclusions: A tenoscopic approach through the carpal flexor sheath provided adequate access for desmotomy of the AL‐DDFT.     

Arthroscopic surgery of the carpal and digital tendon sheaths

Chronic active tenosynovitis of the digital sheath can become increasingly complicated by intrathecal mass and adhesion development, annular ligament constriction, and secondary linear clefting or flattening of the tendons. Endoscopic techniques (tenoscopy) provide a minimally invasive mechanism for thorough digital sheath examination, resection of masses and adhesions, transection of the annular ligament, and debridement of frayed edges after secondary damage. Use of a torniquet, an arthroscope entry point distal to the annular ligament, and instrument portals over the proximal cul-de-sacs of the sheath provide access for tendon and tendon sheath repair. The surgery in advanced cases can be challenging but improvement in work capability and cosmetic appearances are frequently positive. Similarly, a complex form of carpal sheath tenosynovitis can develop from intrusions of bony exostoses and osteochondroma from the radius, tears of the flexor tendons, overextension of the carpus, or fracture of the accessory carpal bone. Tenoscopic examination and debridement within the carpal sheath can assist in rehabilitation. Additionally, the proximal check ligament can be easily transected using carpal sheath tenoscopic techniques. A lateral arthroscope entry proximal to the accessory carpal bone provides access to most clinically relevant regions within the carpal sheath. Instrument portals are made after spinal needle insertion to establish the most appropriate path to the lesion. Removal of bone protrusions and tenosynovial masses, debridement of flexor tendon damage, and release of the carpal retinaculum all offer better chances of improved work capability in a variety of carpal sheath diseases. The examination of the carpal sheath and its contents is more complete than that following open approaches, and a return to rehabilitation exercise programs can be quickly initiated after surgery.     

The incidence and severity of intercarpal ligament damage in the equine carpus

SUMMARY The arthroscopic findings in 104 intercarpal joints in 76 horses were reviewed to determine the incidence and severity of changes in the medial intercarpal ligament. Damage to the intercarpal ligament was observed in 43 joints in 35 horses, ranging from mild fraying of the edges of the ligament to complete disruption of all fibres. This represented an incidence of 41% of joints being affected. In 9 joints examined arthroscopically primarily as a further diagnostic procedure, ligament damage was evident in all cases. In horses undergoing arthroscopic surgery primarily for the treatment of osteochondral chip or slab fractures, there was some correlation between the severity of articular cartilage damage and the presence of ligament damage.     

Ultrasonographic examination of the palmar aspect of the pastern of the horse: Sesamoidean ligaments

The suspensory apparatus is composed of the third interosseous muscle (TIOM) or suspensory ligament, the proximal sesamoid bones, palmar ligament and distal sesamoidean ligaments (DSL). Of these structures, the suspensory ligament is the most frequently implicated in conditions seen in race and sport horses; nevertheless, DSL lesions are not rare and often associated with other injuries that can modify patient prognosis and management. Ultrasonography has been shown to be valuable in the assessment of DSL desmitis. In contrast to the metacarpal area, the pastern region has been considered technically more difficult to scan because of the small and irregular contact surface and frequent artefacts. Advances in imaging techniques with adapted ultrasound probes and the use of magnetic resonance imaging (MRI) for equine lameness evaluation have revealed that distal sesamoidean ligament injuries are more frequently implicated in lameness than previously suspected.     

Intestinal Entrapment and Strangulation Caused by Rupture of the Duodenocolic Ligament in Four Dogs

Objective — The purpose of this study was to describe four dogs with intestinal entrapment and strangulation caused by a rupture of the duodenocolic ligament.
Study Design — This case series documents historical findings, physical examination findings, diagnostic workup, surgical intervention, and outcome of four dogs confirmed at surgery with duodenocolic ligament rupture.
Results — Three of four dogs were German shepherds, and two of three German shepherds were intact males. The history, clinical signs, and physical examination findings were not specific for intestinal entrapment. The clinical signs in three of four dogs included chronic vomiting, diarrhea, anorexia, and lethargy. In the remaining dog, the clinical signs were vomiting and peracute collapse. This dog rapidly deteriorated over a few hours because of strangulation of the entrapped intestines. In two of four dogs, abdominal radiographs showed a distended colon displaced to the right side of the abdominal cavity. Surgery involved transection of the remaining ventral remnant of the duodenocolic ligament and replacing the colon into its normal anatomic position. The three dogs with chronic clinical signs were either still alive, or were euthanatized for unrelated problems. The dog with strangulation of the entrapped intestines was euthanatized at the time of surgery.
Conclusions and Clinical Relevance — Duodenocolic ligament rupture with secondary bowel entrapment can occur in dogs. The prognosis for these animals is favorable provided there is no vascular compromise of the entrapped bowel segments. The peracute history, progression of the disease process, and outcome of the fourth dog in this study indicate that surgery should be performed as an emergency procedure.     

Collateral ligament reconstruction in two horses following traumatic avulsion fracture using a knotless suture anchor construct

This case report describes a technique for repair of medial collateral ligament avulsions in two horses. Both horses sustained traumatic injuries resulting in avulsion fractures at the origin of their medial tarsal and carpal collateral ligaments. This report describes the use of a knotless suture anchor to mechanically reconstruct medial collateral ligament avulsion injuries in two horses. The first horse, a 9‐year‐old Hannovarian Warmblood gelding presented for an acute nonweightbearing lameness in the right hindlimb. The injury was localised to the medial malleolus of the tibia and an avulsion fracture of the origin of the short medial collateral ligament of the tibiotarsal joint with disruption of the ligament was found on radiographs and ultrasound. The horse was taken to surgery and a reconstruction of the short medial collateral ligament was performed with a modified single row construct using a biocompatible, multistrand, long chain ultra‐high molecular weight polyethylene braided composite suture tape (2 mm Fibertape) and a single knotless suture anchor (5.5 × 19.1 mm PEEK SwivelLock C). The second horse, a 5‐year‐old Thoroughbred gelding presented for an acute nonweightbearing lameness in the left forelimb. The injury was localised to the medial styloid process of the radius and an avulsion fracture of the origin of the medial collateral ligament of the antebrachial carpal joint was found on radiographs and ultrasound. The horse was taken to surgery and a similar reconstruction procedure was performed to the collateral ligament. Both horses were recovered in a Robert Jones bandage without the use of casts or splints and recovered without incident. Both horses are sound and returned to previous level of athletic performance at 18 months and 8 months, respectively.     

Intraoperative depression of the bulla of the maxillary septum as a method of improving sinus drainage without epistaxis in horses

Current methods of creating sinus drainage and allowing egress of a sinus pack at the end of surgery create significant haemorrhage. Given that haemorrhage is already a concern in some sinus surgeries, the method described allows for a significant reduction in blood loss. The objective was to describe a method of enlarging the nasomaxillary aperture in horses to allow egress of a sinus pack, and subsequent endonasal treatment, without incurring significant haemorrhage. The bulla of the maxillary septum is depressed using a gloved finger (through a sinus flap or trephine hole) or using a long curved Peine instrument under sinoscopic control before fenestration. No major operative or post-operative complications have been encountered. Satisfactory widening of the nasomaxillary aperture has been accomplished in all cases, although at times, when the bulla is under the floor of the dorsal conchal sinus, it can be difficult to compress. It is imperative that this procedure be performed before fenestration. If performed after fenestration, the most rostral edge of the fenestration can be difficult to identify, and this becomes an impediment to widening the nasomaxillary aperture. Enlarging the nasomaxillary aperture with a finger or blunt instrument allows improvements in sinus drainage without the complication of severe epistaxis. Depression of the bulla of the maxillary septum, before surgical fenestration into the rostral maxillary and ventral conchal sinuses, allows opening of the nasomaxillary aperture with minimal haemorrhage. Thereafter, the sinus pack can be egressed via this route, which is also large enough to perform sinus lavage and post-operative treatments endonasally without the risk of disturbing the external surgical site.     

Long-term Outcome of Standing Medial Patellar Ligament Splitting to Manage Horses Exhibiting Delayed Patellar Release: 64 Horses

A standing surgical technique for splitting the medial patellar ligament is described, and the long-term (average 4.5-years) efficacy of the procedure in horses exhibiting delayed patellar release is reported. Medical records of 64 horses that underwent a standing medial patellar ligament splitting surgery performed to treat delayed patellar release were analyzed retrospectively. Horses were sedated in standing stocks. A number 15 scalpel blade was used to percutaneously split the medial patellar ligament from just proximal to its insertion on the tibial tuberosity to its attachment on the parapatellar fibrocartilage, with the goal of inducing a localized desmitis and subsequent thickening of the ligament. Aftercare consisted of oral antibiotics, 14 days stall rest with hand walking, light exercise for 14 days, and full work at 4 weeks. Follow-up information was obtained through telephone calls to owners and/or clinical evaluation by a veterinarian. Results showed that 89% of horses benefitted from the procedure, with complete resolution in 58% of horses and improvement in 31% of horses. A total of 73% of horses were able to perform at the desired level following the procedure; 63% of horses showed signs of improvement or resolution within 30 to 60 days. Two horses had complications following the procedure: 1 horse had an incisional infection, and 1 had a medial patellar ligament rupture. This study shows that standing medial patellar ligament splitting is a successful, long-term surgical option for treatment of delayed patellar release. The procedure has few complications and allows rapid return to desired performance.     

Endoscopic surgery in the treatment of contaminated and infected synovial cavities

REASONS FOR PERFORMING STUDY: Contamination and infection of synovial cavities are a common occurrence in clinical practice and, if inadequately treated, may have career or life threatening consequences for affected horses. HYPOTHESIS: The objectives in treating contamination and infection of joints, tendon sheaths and bursae are most effectively met by endoscopic surgery. METHODS: Over a 6 year period, cases of synovial contamination and infection admitted to a referral clinic were evaluated and treated endoscopically. The horses received local and systemic antimicrobial drugs with minimal nonsteroidal anti-inflammatory medication but no other medical or surgical treatment. All arthroscope and instrument portals and, whenever possible, all traumatic wounds were closed. Diagnostic information, endoscopic observations and results of treatment were evaluated retrospectively. RESULTS: A total of 140 affected animals were referred and 121 cases were treated endoscopically. These involved 70 joints, 29 tendon sheaths, 10 bursae and in 12 cases a combination of synovial cavities. The most common aetiologies were open wounds (n = 54) and self-sealing punctures (n = 41). Foreign material was identified endoscopically in 41 but predicted prior to surgery in only 6 cases. Osteochondral lesions were evident at surgery in 51 and recognised before surgery in 25 cases; 32 horses had intrathecal tendon or ligament defects. Follow-up information was obtained for 118 animals; 106 (90%) survived and 96 (81%) returned to their preoperative level of performance. The presence of osteitis/osteomyelitis, other osteochondral lesions and marked deposits of pannus were associated with nonsurvival. For those animals which survived, non-Thoroughbred horses, a combination of synovial structure involvement and regional i.v. antimicrobial administration were associated with reduced post operative performance. Marked pannus, regional i.v. antimicrobial administration and duration of systemic antimicrobial administration were associated with a group combining nonsurviving animals and those with reduced post operative performance. CONCLUSIONS: Endoscopic surgery makes a valuable contribution to the management of synovial contamination and infection. POTENTIAL RELEVANCE: The information obtained from and therapeutic options offered by endoscopy justify its early use in cases of synovial contamination and infection.     

Laparoscopic nephron-sparing surgery for the treatment of canine dioctophymosis

This paper reports on two cases of laparoscopic nephrotomy employed in the treatment of canine dioctophymosis, which is considered a unusual procedure and a new treatment proposal heretofore not performed in veterinary medicine. Two patients were treated, one with a history of hematuria and the other with incidental finding of the parasite in the abdominal cavity during elective ovariohysterectomy. Both dogs were subjected to abdominal ultrasound, which produced images indicating the presence of the parasite in the right side kidney, but with partial parenchymal preservation. The patients were therefore subjected to laparoscopic nephrotomy. The surgical procedure was effective in treating dioctophymosis and enabled minimum tissue invasion during surgery, in addition to preservation of the kidney.