Short-term outcome after treatment of talocrural instability in cats using modified type II transarticular external skeletal fixation

Transarticular external skeletal fixation (TESF) is repeatedly used for temporary stabilisation of tarsal joint in cats. Hence, this study aimed to evaluate the use of temporary modified type II TESF for management of talocrural instability (TCI) in cats without joint arthrodesis and to rate short-term outcomes and complications. Medical records of all cats treated for TCI between January 2012 and December 2021 were reviewed. Information was collected including signalment, degree of lameness, type of TCI, accompanying soft tissue and bone injuries, and post-operative follow-up assessment including time of frame removal, complications, degree of lameness, range of joint motion and ankylosis. Surgical management didn't involve debridement of the articular cartilage. Eighty-five percent of cats had satisfactory joint stability at the time of frame removal. Eighteen cats exhibited minor complications, six cats had major complications, and 8 cats showed persistent lameness. All cats showed reduction of joint motion range by 20°-30° directly after frame removal while returned to normal in 79% of cats 4 weeks later. Variable degrees of joint ankylosis were reported. In conclusion, this study supports the use of temporary modified type II TESF for management of TCI in cats without joint involvement as an excellent alternative to tarsal arthrodesis.

Retrospective evaluation of postoperative joint immobilization using a temporary calcaneotibial screw for medial or lateral tarsocrural joint instability in dogs

OBJECTIVE

To evaluate the use of a temporary calcaneotibial screw (CTS) to immobilize medial or lateral tarsocrural joint instability (TCI) in dogs.

STUDY DESIGN

Retrospective study.

ANIMALS

Twelve dogs (including five active working farm dogs) with TCI.

METHODS

Medical records (January 2015-June 2023) were retrospectively reviewed for cases of TCI managed surgically including temporary joint immobilization using a CTS and external coaptation. Clinical data consisted of medical records and an online survey completed by the owner.

RESULTS

Surgical techniques to address TCI included primary ligamentous repair, synthetic ligament reconstruction, or malleolar fracture repair. Immobilization with a CTS was employed for 6-8 weeks postoperatively. The online survey was completed for 10 dogs. All dogs exhibited good-to-excellent functional outcomes at the follow-up (median, 31 months; range, 4-66). All working farm dogs (5) were able to return to normal or substantial levels of their work. Four distinct complications were reported in three dogs including one CTS breakage and three bandage-related soft-tissue injuries.

CONCLUSION

This retrospective study represents the first report of employing a temporary CTS for TCI in dogs.

CLINICAL SIGNIFICANCE

A temporary CTS was effective in immobilizing the tarsocrural joint for dogs with TCI and the postoperative complication rate in this study was relatively low. A CTS screw and external coaptation is a viable alternative to previously reported methods of tarsocrural joint stabilization.

Treatment of Medial Instability of the Carpometacarpal and Tarsometatarsal Joints Using the Isolock® System in Two Dogs

This case report describes a novel procedure using the Isolock Intrauma® implant system for treating medial instability of the carpometacarpal and tarsometatarsal joints, as demonstrated in in two dogs. A 9-year-old spayed female Spanish greyhound presented with a non-weight-bearing right hindlimb following a trauma. The clinical and radiological findings confirmed medial tarsometatarsal instability consistent with valgus deviation of the tarsus and the opening of the joint line on the medial aspect from the first to the third tarsometatarsal joints. A 4-year-old female Drahthaar presented with a non-weight-bearing left forelimb, swelling of the carpus and valgus instability. Radiological examination revealed a widening of the spaces between the intermedioradial carpal bone, second carpal bone and metacarpal bone II, confirming the medial carpometacarpal instability. In both cases, the Isolock system, an implant including ultra-high-molecular-weight polyethylene suture (UHMWPE), was used to reinforce the medial joint structures. Minor short-term complications were observed, such as swelling of the tarsal surgical site and hyperextension of the carpus, but these resolved spontaneously. No lameness or major complications were reported five months postoperatively. Carpometacarpal and tarsometatarsal instabilities are rare diseases in dogs as compared to subluxations of the other joints of the carpus and tarsus. There are no previous reports regarding the use of a UHMPWE implant for the treatment of these rare joint injuries, though the present case report suggests the validity and efficacy of the Isolock Intrauma® implant for restoring carpal and tarsal stability and preserving joint mobility.

Acute limb shortening and modified pantarsal arthrodesis for the treatment of a highly comminuted distal tibial articular fracture in a dog

A three-year-old female spayed Lurcher was referred for the treatment of a highly comminuted distal tibial articular fracture. Resection of the area of comminution with a transverse osteotomy of the tibial diaphysis and talar ridges was performed, followed by modified pantarsal arthrodesis and a calcaneotibial screw. The treatment resulted in 7 cm of tibial shortening, equating to a 28% reduction in the total tibial length. Radiographic union of the arthrodesis was successful. Fair use of the pelvic limb was documented long-term. Combined acute limb shortening and modified pantarsal arthrodesis resulted in an acceptable outcome and could be considered in cases of highly comminuted distal tibial fractures.

Intra-Articular Administration of a Synthetic Lubricin in Canine Stifles

OBJECTIVE

 The aim of this study was to evaluate the functional, systemic, synovial and articular changes after intra-articular administration of a synthetic lubricin within healthy canine stifles.

STUDY DESIGN

 A prospective randomized blinded placebo-controlled study composed of 10 dogs equally divided into either a treatment group (intra-articular synthetic lubricin injection, n = 5) or control group (saline, n = 5). Clinical (orthopaedic examination, gait observation, gait analysis), biochemical (complete blood count and biochemistry profile) and local tissue outcomes (joint fluid analysis, joint capsule and articular cartilage histopathology) were evaluated over a time period of 3 months.

RESULTS

 No significant differences between the treatment group and control group were identified with regard to baseline patient parameters. No clinically significant orthopaedic examination abnormalities, gait abnormalities, biochemical alterations, joint fluid alterations or histopathological alterations were identified over the course of the study.

CONCLUSION

 The synthetic lubricin studied herein is both biocompatible and safe for a single administration within the canine stifle joint. Further research is necessary to evaluate the clinical efficacy of the synthetic lubricin in canine osteoarthritic joints.

Combined internal fixation and transarticular external skeletal fixation to treat traumatic patellar fractures in five dogs

CASE HISTORY

Medical records of dogs (n = 5) that had been treated for patellar fracture with transarticular external skeletal fixation (TA-ESF) to augment internal fixation, at a single referral hospital in the United Kingdom between 2015 and 2017, were reviewed.

CLINICAL FINDINGS AND TREATMENT

At presentation, two dogs had polar patellar fractures, two had comminuted fractures and one dog had a transverse fracture. The median age at the time of the surgery was 21 (min 8, max 132) months and the median body weight was 19.0 (min 8.3, max 28.6) kg. In all cases, TA-ESF (Type IA lateral triangulated or modified Type II) was used in combination with internal fixation with pins and/or orthopaedic wire, supported by nylon leader line (patella-to-tibia mattress suture) and/or absorbable suture in a locking loop and/or circum-patellar pattern. All cases had short-term (6-12 weeks) post-operative radiographic follow-up, which showed evidence of fracture healing in 2/5 cases. All TA-ESF were removed 6 or 7 weeks post-operatively and four dogs had minor complications related to TA-ESF. More than 2 years post-operatively, the owners of all dogs were contacted and questioned using the Liverpool Osteoarthritis in Dogs questionnaire regarding the mobility of their pet. Four of the five cases were re-examined to evaluate their long-term outcomes. Based on the results of goniometric measurement of stifle range of motion, subjective gait assessment and objective gait analysis with a pressure-sensitive walkway, all dogs showed a satisfactory outcome at the final follow-up.

CLINICAL RELEVANCE

A combination of internal fixation and TA-ESF for stabilisation of traumatic patellar fractures is a valid treatment option. Further investigations with larger case numbers are necessary to evaluate success and complication rates.

Evaluation of post-operative complications, outcome, and long-term owner satisfaction of elbow arthrodesis (EA) in 22 dogs

The objective of this study was to report post-operative complications and outcomes in canines undergoing elbow arthrodesis (EA) with fixation techniques including bone plate fixation with a non-locking dynamic compression plate (DCP), bone plate fixation with a locking plate (LCP), and external skeletal fixator (ESF). Medical records of twenty-two cases that underwent EA between January 2009-December 2019 from 8 referral hospitals including both private practice and academic institutions were reviewed. Post-operative complications were classified as either minor or major, surgical evaluations were performed 8 weeks post operatively, and a follow-up questionnaire was sent to owners. Of the total 22 cases that met inclusion criteria, a total of 19/22 cases had complications, 12 major and 7 minor. Complications reported in 8/9, 7/9, and 4/4, for the DCP, LCP, and ESF fixation groups, respectively. Mild to moderate mechanical lameness was identified at surgical evaluation in 16/22 cases. Complete radiographic bone healing was achieved after 9 weeks in 19/22 cases. Long term owner follow up was available in 14/22 cases. Owners reported a good to normal quality of life in 13/14 cases and poor in one case. The majority of owners (11/14) reported good to excellent satisfaction with the outcome irrespective of persistent lameness. This study demonstrates that successful EA can be achieved using a variety of fixation methods, but persistent lameness is expected and complication rate is high.

Usefulness of Imaging Techniques in the Diagnosis of Selected Injuries and Lesions of the Canine Tarsus. A Review

Simple Summary

Tarsal joint lesions are uncommon in dogs but may lead to serious health problems. The most common diseases involving the tarsal joint are osteochondrosis, fractures and injuries of the Achilles tendon. The basis for the diagnosis of lesions in the tarsus is a thorough orthopedic examination, sometimes performed under sedation. Imaging modalities such as radiography, ultrasonography, magnetic resonance imaging or computed tomography can facilitate the detection and assessment of lesions in the canine tarsal joint. The aim of this paper is to characterize and compare the usefulness of imaging techniques available in veterinary medicine for the diagnosis and evaluation of lesions and injuries affecting the tarsal joint in dogs.

Abstract

Tarsus lesions are not common in dogs, but they can cause serious health problem. They can lead to permanent changes in the joint and, in dogs involved in canine sports, to exclusion from training. The most common diseases and injuries involving the tarsal joint are osteochondrosis, fractures and ruptures of the Achilles tendon. These conditions can be diagnosed primarily through accurate orthopedic examination, but even this may be insufficient for performing a proper diagnosis. Imaging modalities such as radiography, ultrasonography, magnetic resonance imaging or computed tomography can facilitate the detection and assessment of lesions in the canine tarsal joint. This review paper briefly presents some characteristics of the above-mentioned imaging techniques, offering a comparison of their utility in the diagnosis of lesions and injuries involving the canine tarsus.

Description and outcome of prosthetic ligament placement for stabilization of medial or dorsomedial tarsometatarsal joint luxation in dogs and cats: 16 cases (2004-2017)

OBJECTIVE

To describe prosthetic ligament placement for reduction and stabilization of medial or dorsomedial tarsometatarsal joint luxation in dogs and cats and to report complications and postoperative outcomes for patients that underwent that procedure.

ANIMALS

14 dogs and 2 cats with medial or dorsomedial tarsometatarsal joint luxation.

PROCEDURES

The electronic database of a referral surgery practice was searched to identify records of dogs and cats with tarsometatarsal joint luxation that underwent prosthetic ligament placement between January 2004 and March 2017. For each study subject, information extracted from the medical record included signalment, a description of the tarsometatarsal joint injury, durations of anesthesia and surgery, and intraoperative and postoperative care and complications. Radiographic images were also reviewed. The long-term outcome for study subjects was assessed by administration of a standardized questionnaire to owners.

RESULTS

Prosthetic ligament placement successfully stabilized the luxated tarsometatarsal joint in all 16 patients. Six patients developed minor postoperative complications, which included bandage-associated dermatitis or ulceration (n = 5) and orthopedic wire failure (1). No major or catastrophic complications were reported. All 13 owners who completed the questionnaire perceived that the described technique resulted in satisfactory long-term function for their pets.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that prosthetic ligament placement was a technically simple procedure that achieved satisfactory long-term stabilization of the tarsometatarsal joint in small animal patients with medial or dorsomedial luxation of the joint. Prosthetic ligament placement may be an alternative to arthrodesis for tarsometatarsal joint stabilization in appropriate patients.

Biomechanical comparison of four prosthetic ligament repair techniques for tarsal medial collateral ligament injury in dogs

OBJECTIVE

To compare joint stability and ultimate strength among 4 prosthetic ligament constructs for repair of tarsal medial collateral ligament (MCL) injury in dogs.

SAMPLE

13 canine cadavers (26 hind limbs).

PROCEDURES

Each limb was stripped of all soft tissues except those associated with the tarsal joint and assigned to 1 of 4 prosthetic ligament constructs. The AN construct consisted of 3 bone anchors connected with monofilament nylon suture. The AU construct consisted of low-profile suture anchors connected with multifilament ultrahigh-molecular-weight polyethylene (UHMWPE) suture. The TN and TU constructs involved the creation of 3 bone tunnels and use of nylon or UHMWPE suture, respectively. Each limb underwent biomechanical testing before and after MCL transection and before and after cyclic range-of-motion testing following completion of the assigned construct. Tarsal joint stability (extent of laxity) was assessed with the joint in each of 3 positions (75°, 135°, and 165°). After completion of biomechanical testing, each limb was tested to failure to determine the ultimate strength of the construct.

RESULTS

Relative to intact tarsal joints, joint laxity was significantly increased following completion of all 4 constructs. Construct type was not associated with the magnitude of change in joint laxity. Ultimate strength was greatest for the UHMWPE-suture constructs.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that all 4 constructs effectively stabilized MCL-deficient tarsal joints. Implants used for the TU, TN, and AU constructs had a lower profile than those used for the AN construct, which may be clinically advantageous. In vivo studies are warranted.

Biomechanical comparison of a modified three-loop pulley technique and a three-level self-locking technique for repair of patellar tendon rupture in dogs

OBJECTIVE

To compare use of a 3-level self-locking suture (3LSLS) technique with use of a previously described modified 3-loop pulley (M3LP) technique to repair rupture of the proximal aspect of patellar tendons in limbs from canine cadavers.

SAMPLE

Paired hind limbs of 6 adult mixed-breed dogs.

PROCEDURES

A limb from each pair was randomly assigned to be repaired by the 3LSLS technique or M3LP technique with size-2 ultrahigh-molecular-weight polyethylene and size-0 monofilament polypropylene suture, respectively. Limbs were prepared, and each patellar tendon was transected at a site chosen to simulate rupture at the proximal aspect. Tendons were repaired with the assigned techniques and mechanically tested with a biaxial servohydraulic test system; the clamp was distracted until the repair failed. Force at 1 -mm gap formation, 3-mm gap formation, and repair failure and gap size at failure were measured and compared between methods. Mode of failure was recorded.

RESULTS

There was no significant difference between methods for the force required to produce a 1 - or 3-mm gap in the repair. The 3LSLS technique required a significantly higher load for complete failure; gap formation immediately before failure was significantly greater for this method than for the M3LP technique. Four of 6 repairs with the M3LP technique and 0 of 6 repairs with the 3LSLS technique failed by suture breakage.

CONCLUSIONS AND CLINICAL RELEVANCE

The 3LSLS technique with size-2 ultrahigh-molecular-weight polyethylene suture was as effective at resistance to 1 - and 3-mm gap formation as the M3LP with size-0 monofilament polypropylene suture.

Effect of a calcaneo-tibial screw on medial and lateral stability of the canine tarsocrural joint ex vivo

Objective: To evaluate the use of a temporary calcaneo-tibial screw for stabilization of the tarsocrural joint in dogs with surgically treated collateral ligament injury.

Methods: The degree of varus and valgus laxity of the tarsocrural joint in various states of injury and stabilization was measured in paired cadaveric limbs of Greyhound dogs. The angle of varus or valgus laxity was calculated following simulated collateral ligament injury (long collateral ligament only, long and short collateral ligaments, and bilateral long and short collateral ligaments) and stabilization with a calcaneo-tibial screw.

Results: The joint was significantly more stable after placement of a calcaneo-tibial screw compared to limbs with any combination of injured collateral ligaments. There was not a significant difference between stability of the intact limb compared to the injured limb with calcaneo-tibial screw fixation.

Clinical significance: Calcaneo-tibial screw fixation appears to be an adequate method of stabilizing the tarsocrural joint following collateral ligament injury, and warrants clinical evaluation as a less expensive alternative to external skeletal fixation application. It is likely that this method would need to be supplemented with a cranial half cast to prevent screw failure during weight bearing.

Comparison of radiography and computed tomography to evaluate fractures of the canine tarsus

Detection and accurate classification of traumatic tarsal fractures are important for identifying cases requiring surgical intervention. The aim of this prospective, experimental, methods comparison study was to directly compare the accuracy, sensitivity, and specificity of tarsal computed tomography (CT), ten-view and two-view digital radiographs for detecting traumatic fractures of the canine tarsus. The working hypothesis was that tarsal fractures would be detected with higher accuracy, sensitivity, and specificity using CT imaging compared to radiography, and a ten-view would be superior to a two-view radiographic study. Ten cadaver hind limbs of medium to large dogs received a CT scan and ten-view radiographic study before and after induction of fractures with a hydraulic press. All bones included in the radiographic images were assessed for fractures by two observers and gross dissection was used as the gold standard. The two-view radiographic study (dorsoplantar, lateromedial) was created from the ten-view study and reviewed 2 years later. All limbs sustained fractures, the most common locations were the talus and calcaneus (n = 7). The sensitivity of CT was greater than ten-view radiographic study (77% vs. 57%), while the specificity was similar (97% vs. 98%). The sensitivity and specificity of the ten-view and two-view radiograph studies were similar (57% vs. 55%; both 98%). Computed tomography images were reassessed postdissection to determine if failure to identify fractures resulted from observer error. Overall, CT was better than radiography for detecting fractures of the canine tarsus, however there was little improvement with ten-view compared to two-view radiographic studies.

Postoperative complications associated with external skeletal fixators in cats

OBJECTIVES

The objective of this study was to quantify complications associated with external skeletal fixators (ESFs) in cats and to identify potential risk factors.

METHODS

A retrospective review of medical records and radiographs following ESF placement was performed.

RESULTS

Case records of 140 cats were reviewed; fixator-associated complications (FACs) occurred in 19% of cats. The region of ESF placement was significantly associated with complication development. Complications developed most frequently in the femur (50%), tarsus (35%) and radius/ulna (33%). Superficial pin tract infection (SPTI) and implant failure accounted for 45% and 41% of all FACs, respectively. SPTI occurred more frequently in the femur, humerus and tibia, with implant failure more frequent in the tarsus. No association between breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, degree of fracture load sharing, and the incidence or type of FAC was identified. No association between region of placement, breed, age, sex, weight, fracture type (open vs closed), ESF classification, number of pins per bone segment, fracture load sharing and the time to complication development was identified.

CONCLUSIONS AND RELEVANCE

Complication development is not uncommon in cats following ESF placement. The higher complication rate in the femur, tarsus and radius/ulna should be considered when reviewing options for fracture management. However, cats appear to have a lower rate of pin tract infections than dogs.