Effect of weight bearing on the joint angles of the fore- and hind limb of the dog

Reconstruction of the flexor carpi ulnaris tendon with a fascia lata autograft in two dogs with carpal hyperextension

OBJECTIVE

To describe the outcome of two dogs treated with fascia lata autografts to repair carpal hyperextension caused by flexor carpi ulnaris (FCU) tendon injury.

ANIMALS

Two dogs with traumatic carpal hyperextension.

STUDY DESIGN

Case report.

METHODS

Radiographic abnormalities were detected in the antebrachiocarpal joint of each dog. Damage to the FCU tendon were located at the ulnar head on ultrasonographic and intraoperative examinations. Each injured tendon was reconstructed with a fascia lata graft. The radius and metacarpal bones were immobilized by a type I external skeletal fixation for 6 weeks.

RESULTS

No difference was detected between the operated and contralateral limbs on postoperative examination, including range of motion, and angles of the carpus during standing or extension stress. No recurrence of carpal hyperextension was observed over 36 months after surgery.

CONCLUSION

Carpal hyperextension was successfully treated by primary repair of the damaged area and reinforcement with fascia lata and maintained long-term joint mobility in two dogs.

Mechanical Evaluation of Two Hybrid Locking Plate Designs for Canine Pancarpal Arthrodesis

Hybrid locking pancarpal arthrodesis plates were designed with either a round (RH) or an oval (OH) radiocarpal hole, the latter allowing varied screw positioning. Due to concerns about potential decreased structural properties of the OH design, our aim was to compare the mechanical behavior of the contrasting plates using combined finite element analysis (FEA) and mechanical testing. Pancarpal arthrodesis plates with RH or OH design were assigned to three fixation techniques (n = 6), prebent at 20°, and fixed to canine forelimb models with simulated radius and radiocarpal and 3rd metacarpal bones. OH plates were instrumented with a radiocarpal screw inserted either most proximal (OH-P) or most distal (OH-D). Specimens were axially loaded to 300 N over 10 ramped cycles at 0.5 Hz. Plate strains were measured with strain gauges placed at areas of highest deformations as predicted by FEA under identical loading conditions. FEA predicted the highest strains (μm/m) adjacent to the radiocarpal hole (2,500 [RH], 2,900 [OH-P/OH-D]) and plate bending point (2,250 [RH], 1,900 [OH-P/OH-D]). Experimentally, peak radiocarpal hole strains were not influenced by the OH screw position (3,329 ± 443 [OH-P], 3,222 ± 467 [OH-D]; P = 0.550) but were significantly higher compared to the RH design (2,123 ± 154; P < 0.001). Peak strains at the bending point were significantly lower for OH-P (1,792 ± 174) and OH-D (1,806 ± 194) versus RH configurations (2,158 ± 114) (P ≤ 0.006). OH plates demonstrated highest peak strains next to the radiocarpal hole and were associated with more heterogenous plate strain distribution. Structural weakening associated with radiocarpal OH plate design could result in decreased fixation strength and increased risk of plate fatigue failure.

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.

Comparison of Outcome and Complications in Dogs Weighing Less Than 12 kg Undergoing Miniature Tibial Tuberosity Transposition and Advancement versus Extracapsular Stabilization with Tibial Tuberosity Transposition for Cranial Cruciate Ligament Disease with Concomitant Medial Patellar Luxation

OBJECTIVE

 The aim of this study was to describe a technique for performing miniature tibial tuberosity transposition and advancement (mTTTA). The secondary objective of this study was to compare the short-term outcome and complications in small breed dogs weighing less than 12 kg undergoing surgical correction of cranial cruciate ligament disease with concurrent medial patellar luxation via either extracapsular stabilization with tibial tuberosity transposition (ECS + TTT) or mTTTA.

STUDY DESIGN

 This is a retrospective case comparison study.

RESULTS

 There was no significant difference in overall outcome between the ECS + TTT group and the mTTTA group when comparing 8-week postoperative radiographic healing scores as well as 2- and 8-week postoperative lameness scores.

CONCLUSION

 This study concluded that the mTTTA procedure was feasible and the overall outcome and complications for the dogs that underwent ECS + TTT and those that underwent mTTTA were comparable.

Prosthesis design of animal models of periprosthetic joint infection following total knee arthroplasty: A systematic review

BACKGROUND

The number of periprosthetic joint infections (PJI) after total knee arthroplasty (TKA) is increasing annually. Animal models have been used to clarify their clinical characteristics and the infection mechanism of pathogenic bacteria, However, since the prosthesis design of animal models is not uniform, it is difficult to simulate the environment of clinical PJI.

OBJECTIVES

To retrospect the progress on the prosthesis design of animal models of PJI after TKA and to summarize the criteria for evaluating a clinically representative model of PJI.

METHODS

This systematic review was reported on the basis of Systematic Reviews and Meta-Analyzes (PRISMA). Pubmed, EMbase, Cochrane Library, Web of Science, Wanfang Data and China National Knowledge Infrastructure were researched for animal models of PJI after TKA from database establishment to April 2019 according to Chinese and English retrieval words, including "periprosthetic joint infections and total knee arthroplasty," "periprosthetic joint infections and model," "periprosthetic joint infections and biofilm," and "total knee arthroplasty and model."

RESULTS

A total of 12 quantitative studies were enrolled in our study finally: 8 representative studies described prosthesis designs used in PJI animal models, 4 studies described prosthesis designs in non-infected animal models which were suitable for infection models. The major problems need to be dealed with were prosthesis, installation location, material, the function of separating the articular and medullary cavity, fixation manner, and the procedure of preserving the posterior cruciate ligament.

CONCLUSION

A highly representative design of the animal prosthesis of PJI should meet the following criteria: the surface of the prosthesis is smooth with the formation of biofilm, composed of titanium-6Al-4V or cobalt-chromium-molybdenum alloy; prosthesis can bear weight and is highly stable; and it can connect the joint cavity and medullary cavity simultaneously. To reach a more reliable conclusion, further experiments and improvements are required.

Stifle arthrodesis in two cats

Two Domestic Shorthaired cats were admitted after sustaining multiligamentous injuries of the stifle joint. In one cat, prosthetic ligamentous reconstruction was unsuccessful at maintaining normal stifle stability. Both cats were treated with stifle arthrodesis using internal fixation with a plate and screws without external coaptation. In one case, arthrodesis was achieved using a 2.7 mm 16-hole dynamic compression plate placed medially. In the second case, a 2.7 mm 14-hole dynamic compression plate was placed cranially. No major complications were noted, and both cats were able to return to good levels of activity in the medium term.

Shoulder arthrodesis in 14 dogs

OBJECTIVES

To report surgical technique and clinical outcome of shoulder arthrodesis in dogs.

STUDY DESIGN

Multicenter clinical case series.

ANIMALS

Dogs (n = 14).

METHODS

Shoulder arthrodesis featured craniolateral plate and screw application, with application of a 2nd plate and screws craniolaterally or caudolaterally in 5 shoulders. Implants included the locking string of pearls (SOP)™ plate in 7 shoulders. Subjective preoperative, 5-8 weeks postoperative, and 11-16 weeks postoperative clinical and radiographic findings were documented. Owner questionnaire evaluation of outcome was performed 6-20 months postoperatively.

RESULTS

Mean angle of arthrodesis was 114° (range 102°-122°). Progression of arthrodesis was noted in 13/14 cases at both the 5-8 and 11-16 weeks postoperative radiographic assessments. Nine complications occurred in 7/14 dogs, graded as catastrophic in 2/9, major in 2/9, and minor in 5/9. Where morbidity was successfully managed, 11-16-week and 6-10-month postoperative limb function was positive on both veterinary and owner evaluations in almost all cases, and in several, functional lameness was considered sufficiently mild as to be imperceptible on subjective veterinary evaluation. Where present, limb circumduction was noted as the major feature of persistent lameness.

CONCLUSIONS

Shoulder arthrodesis in dogs results in acceptable limb function and should be considered for the management of debilitating shoulder pathology despite a high incidence of complications. Application of the SOP plate to aid shoulder arthrodesis warrants further study.

Traumatic Luxations of the Appendicular Skeleton

Traumatic luxation of joints of the appendicular skeleton is common.Timely and accurate identification of the luxation is essential to restoring normal function. Physical examination and radiographic assessment are commonly utilized for accurate identification and categorization. Conservative and surgical techniques are employed for treatment of luxations solely and in combination. Selection of appropriate reparative techniques is dependent on the joint injured as well as on other joint- and injury-specific factors.