Arthroscopic-Assisted Toggle Rod Stabilization in Canine Coxofemoral Luxation: A Cadaveric Study

OBJECTIVE

 The aim of this study was to describe an arthroscopic-assisted technique for coxofemoral toggle rod placement, and to report on the feasibility, drill tunnel trajectory and accuracy of tunnel aperture location using this method.

STUDY DESIGN

 Cadaveric pilot study.

SAMPLE POPULATION

 Eight coxofemoral joints.

METHODS

 Craniodorsal coxofemoral joint luxations were artificially created. A simulated open hip reduction and stabilization with a toggle rod were performed through a limited arthrotomy under arthroscopic guidance. Computed tomography scans were performed to evaluate drill hole trajectory across the femoral neck, and joints were disarticulated and photographed. Digital imaging software was used to determine the percent overlap of the drill hole apertures relative to the origin and insertion of the round ligament on the acetabulum and fovea.

RESULTS

 The exit point of the tunnel was entirely within the fovea capitis in five of eight femurs, three of eight femoral drill apertures were only partially within the target area. Of the eight acetabular bone tunnels examined, all were centred occupying the acetabular fossa.

CONCLUSIONS

 Coxofemoral toggle rod placement can be performed under arthroscopic guidance through a limited arthrotomy. Comparable femoral tunnel accuracy with the standard open technique should be achieved with the current method prior to its clinical use.

Open hip reduction using a novel transarticular suture stabilisation technique in 24 dogs: a retrospective study of technique, outcome and complications

CASE HISTORY

Medical records of a single private practice (Illinois, USA) were retrospectively reviewed to identify dogs (n=24) that had an open hip reduction with a transarticular suture stabilisation technique after presenting with a traumatic coxofemoral luxation between April 2003 and December 2018.

CLINICAL FINDINGS

Dogs that met the inclusion criteria were of various breeds with a median body weight of 18.1 (min 4.2, max 54.5) kg and mean age at presentation of 6.5 (min 1, max 11) years. The surgical technique, short term outcome and complications were extracted from the medical records. Long-term (>2 years) follow-up data was obtained by a telephone interview with each owner.

TREATMENT AND OUTCOME

All dogs underwent open hip reduction using a novel transarticular suture stabilisation technique. The outcome was reported by owners to be excellent in (18/24) 75% dogs with full return of limb function. Sixty-six percent (16/24) of owners reported that no lameness was observed 2 months after surgery. No minor complications were noted in this study. The hips of 6/24 (25%) dogs reluxated after surgery (defined as a major complication), which required femoral head and neck excision surgery.

CLINICAL RELEVANCE

Open coxofemoral joint reduction using a novel transarticular suture technique is a viable surgical option to consider in dogs that present with a traumatic coxofemoral luxation.

Complications and outcomes of cats with coxofemoral luxation treated with hip toggle stabilization using ultrahigh-molecular-weight-polyethylene or nylon (2009-2018): 48 cats

OBJECTIVE

To report overall rate and type of complications and outcomes of cats with coxofemoral luxation managed with hip toggle stabilization (HTS), to compare rate of postoperative complications and outcomes of cats treated with ultrahigh-molecular-weight-polyethylene (UHMWPE) or nylon, and to identify risk factors for reluxation and non-excellent outcomes.

STUDY DESIGN

Multi-institutional retrospective cohort study.

SAMPLE POPULATION

Forty-eight client-owned cats.

METHODS

Medical records of cats that underwent HTS from 2008-2018 using UHMWPE or nylon were reviewed. Univariable and multivariable logistic regression was performed to assess for factors associated with reluxation and non-excellent outcome. Final outcome was obtained from owner questionnaire.

RESULTS

Intraoperative and postoperative complications were recorded in two (4.2%) and 11 (24.4%) cats, respectively. The most common postoperative complication was reluxation (n = 5 [11.1%]). Outcome was classified as excellent in 81.1% and good in 16.2% of cats after a median of 445.5 days (range, 53-3720). No difference in rate of complications or outcomes was identified between UHMWPE and nylon. Performance of additional orthopedic procedures, occurrence of intraoperative complications, and non-performance of capsulorrhaphy were associated with reluxation. Performance of additional non-hip procedures (orthopedic/nonorthopedic) was associated with non-excellent outcome.

CONCLUSION

Hip toggle stabilization was associated with a low rate of intraoperative complications and reluxation and excellent long-term outcomes in most cats. No difference in rate of postoperative complications or outcomes of cats treated using UHMWPE or nylon was identified. Cats that underwent additional orthopedic procedures had greater risk of reluxation.

CLINICAL SIGNIFICANCE

Hip toggle stabilization is an effective technique for management of coxofemoral luxation in cats. Comparable results are expected using UHMWPE or nylon.

Traumatic joint luxations in cats: Reduce, repair, replace, remove

PRACTICAL RELEVANCE

Traumatic joint luxations are usually associated with significant trauma and there may be concomitant systemic injury. Joints are unstable as a result of injury to one or more supporting structures and the clinician should aim to determine which structures are damaged with physical examination, diagnostic imaging and careful assessment under sedation/anaesthesia. The aim is to reduce the joint back to its anatomical position, and then to maintain this through repair of damaged structures. However, where this is not possible, replacement or removal (arthrodesis/excision arthroplasty) of the joint remain viable options.

CLINICAL CHALLENGES

Owing to the small size of feline joints and the severity of damage often seen, surgical management of these cases can be challenging. The first priority is to ensure the patient is systemically well before embarking on any specific surgical treatment of a luxated joint. Cats also present challenges in the postoperative period and a lack of patient and owner compliance can be detrimental to postoperative outcomes.

AIMS

This article aims to help the reader diagnose joint luxations and to assist decision-making with an overview of the management and treatment options available.

EVIDENCE BASE

There are a number of original articles and textbook chapters in the literature covering aspects of different joint luxations, particularly for the more common luxations. This article draws on information from key feline research and, where necessary, extrapolates from relevant canine research. The authors also offer practical guidance based on their own clinical experience.

Crimped monofilament nylon leader for median sternotomy closure in 10 dogs

OBJECTIVE

To describe and report the outcomes after closure of median sternotomies with crimped monofilament nylon leader (MNL) in dogs.

STUDY DESIGN

Retrospective observational study.

ANIMALS

Dogs (n = 10) that underwent intrathoracic surgery through a median sternotomy approach.

METHODS

The median sternotomy was closed in a peristernal figure eight pattern with crimped MNL. Medical records were reviewed for clinical and histopathological findings and complications. Owners or veterinarians were contacted to collect long-term follow-up information.

RESULTS

The technique was simple, with no intraoperative complications. Postoperative infection was documented in one dog, requiring removal of a single MNL and associated crimp clamp. Delayed healing of the surgical incision in one dog was managed conservatively. No other complications were documented throughout long-term follow-up at a median of 488 days (range, 199-608).

CONCLUSION

Median sternotomies were successfully closed with crimped MNL and were associated with a low complication rate.

CLINICAL SIGNIFICANCE

Crimped MNL represents an alternative method to close median sternotomies in dogs.

Risk factors for reluxation after toggle rod stabilization for treatment of coxofemoral luxation in 128 dogs

OBJECTIVE

Evaluate the risk factors for reluxation and outcomes for dogs with a toggle rod construct.

STUDY DESIGN

Retrospective case series.

ANIMALS

One hundred twenty-eight client-owned dogs.

METHODS

Medical records from 2007 to 2018 were reviewed for signalment, history, surgery, and outcome for dogs with a coxofemoral luxation repaired with a commercial toggle rod and nylon monofilament suture construct. Univariate and multiple logistics regression analysis were performed to assess risk factors associated with postoperative luxation. Primary veterinarians and owners were contacted for follow-up via telephone or electronic communication.

RESULTS

The overall complication rate was 24.2%, and the reluxation rate was 14.8%. There was a decreased risk of reluxation when the cause was traumatic in origin (odds ratio [OR] 0.10) or when the lameness was severe at presentation (OR 0.42). Fifteen of 58 (25.9%) owners contacted completed a follow-up survey.

CONCLUSION

Dogs with nontraumatic, low impact luxations were at a higher risk for reluxation.

CLINICAL SIGNIFICANCE

Dogs of any body condition with a traumatic coxofemoral luxation are at lowest risk for reluxation.

Coxofemoral Joint Luxation in Dogs Treated with Toggle Rod Stabilization: A Multi-Institutional Retrospective Review with Client Survey

Coxofemoral luxation is the most common type of joint luxation observed clinically in dogs. This retrospective study determines the complications and outcomes of open reduction and internal fixation of coxofemoral luxations using a toggle rod stabilization in 58 dogs. The purpose of the study was to compare the results with previous studies to ascertain commonalities and differences. A majority of the canine luxations were stabilized using a 4.0 or 3.2 mm commercial toggle rod and either one or two strands of OrthoFiber, FiberWire, or monofilament nylon suture. Postoperative complications developed in 25 of the 58 (43%) dogs, with major complications in 9 cases (15.5%). The most common major complication was reluxation, which occurred in 6 dogs (10%). Five of the 6 cases of reluxation received monofilament suture, although there was not a statistically significant relationship between suture type and reluxation. Owner responses to a questionnaire reported good to excellent results for satisfaction with the procedure in 90% of cases. Results of the present study suggest that toggle rod stabilization remains an effective method for the treatment of coxofemoral joint luxation in dogs.

Biomechanical evaluation of a non-locking pre-manufactured loop suture technique compared to a three-loop pulley suture in a canine calcaneus tendon avulsion model

Objective: The purpose of this cadaveric study was to compare the strength of a non-locking pre-manufactured loop (Speed -Whip™ [SW]) suture pattern using Fiber-wire® with the three-loop pulley (TLP) suture pattern using polypropylene for the surgical repair of canine calcaneal tendon avulsion injuries.

Methods: In vitro biomechanical study using 22 paired tendons collected from 11 canine cadavers. Paired tendons were repaired with either a SW suture pattern using Fiberloop® suture or a TLP suture pattern using polypropylene suture. Tensile loads required to create a 1 mm gap, 3 mm gap, and construct failure were measured.

Results: The mean loads to achieve a 1 mm gap in the TLP and SW constructs were not significantly different. Gap formation at 3 mm occurred at significantly lower loads for the SW (106.4 ± 21.5N) than for the TLP (127.2 ± 27.5N) (p = 0.05). The mean loads to construct failure for the TLP (172.8 ± 39.4N) and SW (131.3 ± 34.3N) were significantly different (p = 0.001).

Clinical significance: The TLP with polypropylene suture is superior to the SW using Fiberloop® at resistance to 3 mm gap formation.