Prospective Evaluation of a Citrate-Based Biomaterial Wedge for a Modified Maquet Procedure in the Treatment of Cranial Cruciate Ligament Rupture in Dogs.

OBJECTIVE: The aim of this study was to describe short- and mid-term outcomes, complications, implant bioabsorption and owner satisfaction for a modified Maquet procedure (MMP) in which a novel bioabsorbable citrate-based implant is used as the wedge component to treat cranial cruciate ligament rupture in client-owned dogs. STUDY DESIGN: Prospective clinical study of dogs (n = 13) undergoing MMP (n = 15). Intraoperative complications, postoperative complications, clinical follow-up using a 5-point lameness score and radiographs at 8 weeks and 6 months postoperatively were obtained. Mid-term outcome was assessed via physical examination, radiographs, canine orthopaedic index and owner satisfaction questionnaires. RESULTS: No catastrophic complications occurred. Major complications occurred in 3/15 stifles. All were surgical site infections and one case required implant removal. Minor complications occurred in 9/15 stifles. Non-displaced cortical hinge fractures were the most common minor complication, and these occurred intraoperatively (4/15) or postoperatively (2/15). Three dogs achieved full function, eight dogs acceptable function and the outcome was unacceptable in two dogs. Most owners were satisfied with the procedure (11/13). Complete implant bioabsorption was not confirmed on mid-term radiographs. CONCLUSION: The described MMP with a citrate-based implant can produce satisfactory mid-term results. However, the long-term outcome of this procedure must be evaluated and technical modifications need to be implemented prior to larger-scale use of this implant.

A novel tibial tuberosity advancement technique with cranial implant fixation (TTA CF): a pilot study in sheep.

BACKGROUND: Cranial cruciate ligament rupture is the most frequent orthopedic disorder in human and animals. An array of surgical techniques have been described to stabilize the stifle joint in dogs, including intraarticular stabilization, extraarticular stabilization, and tibial osteotomy techniques. Tibial plateau leveling osteotomy and tibial tuberosity advancement with a lot of modifications are the most common. In this study we report the possibility of fixing the novel titanium implant for tibial tuberosity advancement with two screws in a craniocaudal direction. The aim of our study was to improve the clinical benefit of the tibial tuberosity advancement surgical technique where an attempt was made to reduce the number of screws and obtain a strong implant fixation with minimal bone traumatization. This way of attachment allows to distribute the forces evenly on medial and lateral side of osteotomy gap. RESULTS: Tibial tuberosity advancement with cranial implant fixation was performed in four sheep. Complete radiographic and clinical follow up was recorded. All four sheep had a complete osteotomy line healing at a mean of 10 weeks postoperative (range 8-12 weeks). None of the animals had osteotomy gap healing grades of poor. Minor complication included the minimally cracked Maquet hole on the postoperative radiographs, without displacement of the tibial crest which occurred in 2 sheep. Major complication grade 1, major complication grade 2 and catastrophic were not found. CONCLUSIONS: The novel surgical technique for tibial tuberosity advancement with cranial implant fixation is technically comparable to the recent trend in tuberosity advancement techniques, where partial osteotomy of the cranial tibial tuberosity crest is performed. A cranial implant fixation allows to distribute the forces evenly on medial and lateral side of osteotomy gap, which may result in less number of major complications in dogs. A novel titanium implant decreases the tibial traumatisation by reducing the number of screws.

Use of Synthetic Osteochondral Implants to Treat Bilateral Shoulder Osteochondritis Dissecans in a Dog.

CASE DESCRIPTION: An 8-month-old American Bulldog was presented for assessment of bilateral thoracic limb lameness. Computed tomographic imaging revealed large, deep osteochondritis dissecans lesions in both humeral heads. TREATMENT AND OUTCOME: The osteochondritis dissecans lesions were debrided and the exposed subchondral defects were prepared to receive synthetic grafts. Circular implants consisting of a surface layer of polycarbonate urethane and a deep layer of lattice-type titanium were implanted into the osteochondral defects to reconstruct the articular surface topography. Follow-up clinical examination 1.5, 3 and 9months postoperatively revealed a lack of signs of shoulder pain and resolution of thoracic limb lameness. Nine-month follow-up radiographs showed radiographic evidence of osteointegration of both implants. CLINICAL RELEVANCE: Synthetic osteochondral implantation in the caudocentral aspect of the humeral head appeared technically feasible and effective in resolving lameness caused by humeral head osteochondritis dissecans.

Physical rehabilitation after total joint arthroplasty in companion animals.

Patients who have total joint arthroplasty have varying needs related to rehabilitation. In the short term, rehabilitation should be used in all dogs to identify high-risk patients and to minimize the likelihood of postoperative complications. Many patients undergoing total hip replacement recover uneventfully without needing long-term physiotherapy. All patients undergoing total knee replacement and total elbow replacement need rehabilitation to restore limb use and maximize their functional recovery. This article presents rehabilitation considerations for companion animals undergoing total hip replacement, total knee replacement, and total elbow replacement; postoperative complications and how to mitigate risks; and anticipated patient outcomes.

Ex vivo kinematic studies of a canine unlinked semi-constrained hybrid total elbow arthroplasty system.

OBJECTIVES: Introduction of the Sirius® canine total elbow arthroplasty system, and presentation of the results of a passive range-of-motion analysis based on ex vivo kinematic studies pre-and post-implantation. MATERIALS AND METHODS: Thoracic limbs (n = 4) of medium sized dogs were harvested by forequarter amputation. Plain orthogonal radiographs of each limb were obtained pre- and post-implantation. Limbs were prepared by placement of external fixator pins and Kirschner wires into the humerus and radius. Each limb was secured into a custom-made box frame and retro-reflective markers were placed on the exposed ends of the pins and wires. Each elbow was manually moved through five ranges-of-motion manoeuvres. Data collected included six trials of i) full extension to full flexion and ii) pronation and supination in 90° flexion; a three-dimensional motion capture system was used to collect and analyse the data. The Sirius elbow prosthesis was subsequently implanted and the same measurements were repeated. Data sets were tested for normality. Paired t-tests were used for comparison of pre- and post-implantation motion parameters. RESULTS: Kinematic analysis showed that the range-of-motion (mean and SD) for flexion and extension pre-implantation was 115° ± 6 (range: 25° to 140°). The range-of-motion in the sagittal plane post-implantation was 90° ± 4 (range: 36° to 130°) and this reduction was significant (p = 0.0001). The ranges-of-motion (mean and SD) for supination and pronation at 90° were 50° ± 5, whereas the corresponding mean ranges-of-motion post-implantation were 38° ± 6 (p = 0.0188). CONCLUSION: Compared to a normal elbow, the range-of-motion was reduced. Post-implantation, supination and pronation range-of-motion was significantly reduced at 90° over pre-implantation values. CLINICAL RELEVANCE: These results provide valuable information regarding the effect of the Sirius system on ex vivo kinematics of the normal canine elbow joint. Further, this particular ex vivo model allowed for satisfactory and repeatable kinematic analysis.

Advances in total joint replacement in small animals.

Total joint replacement is now considered a routine surgical option for small animals with advanced joint disease. This review highlights the current state of the art in total hip, elbow and knee replacement in small animals, as well as the potential for application to other joints such as the intervertebral discs, hock and shoulder. Advances in cementless fixation, the use of less-invasive, bone-sparing procedures, and the development of custom implant options for revision surgery and oncologic reconstruction will be discussed. As growth in this field continues, it is important that future developments in total joint replacement are built on a foundation of detailed laboratory evaluation of new implant designs and surgical techniques, objective assessment of clinical outcomes, and a comprehensive, coordinated retrieval program that evaluates both well-functioning and failed joint replacements.

The first case of a Staphylococcus pseudintermedius infection after joint prosthesis implantation in a dog.

We have reported a bacterial infection in a dog with progressive dysplasia of the hips. Orthopedic surgery was performed. Seven weeks prior to the surgery, the patient was bitten by another dog. The postimplantation wound exuded for four days after the surgery. Microbiological analysis performed by standard identification techniques showed the presence of Staphylococcus intermedius, but an additional molecular analysis indicated S. pseudintermedius. This was followed by an evaluation of antibiotic susceptibility of the strain which showed cefoxitin, ciprofloxacin, clindamycin, trimethoprim/sulfamethoxazole, doksycycline, erythromycin, and gentamicin resistance. Minimal inhibitory concentration (MIC) values for selected antibiotics were reported. Resistance for cefoxitin indicates that methicillin resistant S. pseudintermedius (MRSP) strains were present in individual macroorganisms, but they can expand and persist the colonization of other hosts.

[Numerical investigations of the strain adaptive bone remodelling in the periprosthetic canine femur]. / Numerische Untersuchungen zum beanspruchungsadaptiven Knochenumbau im periprothetischen caninen Femur.

After surgical treatment of severe hip diseases with artificial joint prostheses aseptic loosening of the implants can occur. Unphysiologic load distribution in the periprosthetic femur and stress shielding by the prosthesis can result in bone remodelling processes. In particular a cutback of the bone mass is followed by an aseptic loosening of the prosthesis. In this context the understanding of bone remodelling processes in the prothetically treated femur is of outstanding interest for the optimisation of canine hip joint prostheses in the future. Therefore the main aim of this sudy was the numerical investigation on the change in the load distribution in the canine periprosthetic femur and the resulting bone remodelling after implantation of the cemented stem Bioméchanique. The investigations within this study were carried out using the Finite Element Analysis (FEA). The calculated bone density of the periprosthetic femur and the evolution of the mass loss show relevant stress shielding areas in different analysis regions. Therefore possible regions of aseptic loosening are indicated particularly in the proximo-medial femur. The here demonstrated numerical results are in agreement with clinical findings. For this reason the FEA-based method is a valuable tool for the prediction of bone remodelling processes.

Complications of orthopaedic surgery in horses.

Complications are a price all surgeons eventually pay. Experience and increasing skill will decrease many of them but certainly not all. The most important thing is for the surgeon to react correctly to a complication. Acknowledge the mistake (or bad luck) quickly and take whatever steps you can to correct the problem. Because so many equine orthopaedic cases have the potential for complications, recognizing and responding properly to these complications are imperative for successful outcomes. Discussion of the most common complications, their prevention and corrections, is presented.

Excision arthroplasty of the interphalangeal joint as an alternative to digit amputation in two dogs.

Excision arthroplasty of the interphalangeal joint was used as an alternative to digit amputation for comminuted fractures of the phalangeal bones in two dogs. Both patients had return of pain-free use of the affected limb, even though both weight-bearing digits were involved in one case. This type of surgery might prove to be superior to the more invasive digit amputation, salvaging the digits and providing a better functional outcome.

Short-term outcome after total elbow arthroplasty in dogs with severe, naturally occurring osteoarthritis.

OBJECTIVE: To evaluate limb function in client-owned dogs before and after total elbow arthroplasty (TEA) for severe, naturally occurring osteoarthritis (OA). STUDY DESIGN: Prospective clinical evaluation comparing limb function before and after surgery. ANIMALS: Twenty adult, large breed dogs with elbow OA. METHODS: Physical, radiographic, and force platform gait examinations were performed on all dogs before surgery. TEA was performed, and examinations were repeated at 3, 6, and 12 months after surgery. Pre- and postoperative findings were compared. RESULTS: TEA led to a satisfactory outcome in 16 dogs. In dogs with a satisfactory outcome, function in the operated limb increased over time, with mean peak vertical force (PVF) and vertical impulse (VI) 1 year after surgery being nearly twice the presurgical value. Serious complications encountered included infection (n = 2), luxation (n = 1), and fracture of the humeral condyle (n = 1). CONCLUSIONS: Although TEA, as presented, has significant limitations, it can be successfully performed in dogs with naturally occurring elbow OA. Improvements in technique and implant design should lead to improved prognosis. CLINICAL RELEVANCE: Based on 1-year data, TEA can be successfully performed in dogs and should be considered as a treatment alternative for adult dogs with lameness from severe OA of the elbow joint.

Radiologic, mechanical, and histologic evaluation of 2 glenoid prosthesis designs in a canine model.

Aseptic loosening of glenoid components is a common problem associated with total shoulder arthroplasty. A new glenoid design aimed at improving fixation outcomes was compared with conventional keeled glenoids in weight-bearing canine shoulders. Radiographic, histologic, and mechanical tests were performed at 3 postoperative intervals (0, 3, and 6 months). The uncemented pegged glenoid achieved bone ingrowth around the peg flanges in each case. This result was confirmed histologically and radiographically. Mechanical results indicated that mean fixation strength increases significantly between 0 and 3 months after surgery and remains strong through 6 months. In contrast, conventional keeled glenoids were found to have partial or complete radiolucent lines around the keel in each instance, and mechanical testing demonstrated that mean fixation strength weakens significantly between 0 and 3 months after surgery and remains weak through 6 months. These results show that stem design changes can improve implant fixation. A cementless fluted peg stem was superior to a conventional cemented keel design in achieving osseous integration and fixation in a weight-bearing animal model.

Evaluation of a canine total-elbow arthroplasty system: a preliminary study in normal dogs.

OBJECTIVE: Short-term, in vivo evaluation of a total-elbow arthroplasty (TEA) system in normal dogs. STUDY DESIGN: Prospective evaluation comparing pre- and postoperative findings. ANIMALS: Six normal, skeletally mature, large-breed dogs. METHODS: Physical, radiographic, and force-plate gait examinations were performed on all dogs before surgery. TEA was performed in the dogs using a canine TEA system. Examinations were repeated every 8 weeks for 24 weeks, with an additional examination at 52 weeks. Pre- and postoperative findings were compared. RESULTS: The TEA led to an excellent outcome in 3 of 6 dogs. Force-plate gait examination found that the dogs continued to improve over time and had a peak vertical force (PVF) in the surgical limb that was 99.6% of normal (range, 95.8% to 106.4%) 52 weeks after surgery. Major problems encountered during the postoperative time period were non-weight-bearing lameness (1 dog), osteomyelitis (1 dog), and fracture of the ulna (1 dog). CONCLUSIONS: TEA can be successfully performed in dogs. CLINICAL RELEVANCE: Based on 1-year data, TEA can be successfully performed in dogs and could be considered as a treatment alternative for adult dogs with severe osteoarthritis and lameness of the elbow joint.

Biomechanical properties of braided polyester tapes intended for use as intra-articular cranial cruciate ligament prostheses in dogs.

OBJECTIVE: To determine the in vitro structural and material properties of braided, multifilament, nonabsorbable polyester tapes, used for intra-articular stabilization of cranial cruciate ligament- (CCL-) deficient stifle joints in dogs, and compare those with properties of multifilament polyamide tapes. SAMPLE POPULATION: 30 polyester tapes (width, 4 mm), 10 polyester tapes (width, 7 mm), and 30 polyamide tapes (width, 4 mm) were tested to failure. Cyclic loading experiments were also performed, using 3 polyester tapes of each width. PROCEDURE: Tapes were mounted in a tensile tester as single loops, simulating intra-operative conditions, and elongated to failure at 1,000 mm/min. Additionally, the behavior of polyester tapes was tested at different elongation rates. In a second series of experiments, biomechanical variables of the polyester tapes were measured after 25 sets of 2,000 cycles between physiologic force limits. RESULTS: Mean (+/- SD) ultimate loads of the 4-mm wide polyamide tapes, 4-mm wide polyester tapes, and 7-mm wide polyester tapes were 266.48 +/- 13.19 301.78 +/- 16.92, and 726.40 +/- 37.74 N, respectively. Corresponding stiffnesses were 15.57 +/- 0.49, 21.63 +/- 2.19, and 34.85 +/- 2.66 N/mm, respectively. Failure properties of polyester tapes were affected by previous cyclic loading. CONCLUSIONS AND CLINICAL RELEVANCE: Polyester tapes of 4- or 7-mm widths should be able to resist forces resulting from weight bearing in dogs, suggesting that these tapes will be effective for stabilization of the stifle joint in dogs with a ruptured CCL.

Collateral ligament prosthesis for the repair of subluxation of the metatarsophalangeal joint in a jersey cow.

A two-and-a-half-year-old Jersey cow had been moderately lame in its right hindlimb for one month. Clinical and radiographic examinations revealed an incomplete lateral luxation of the metatarsophalangeal joint. The medial condyle of the metatarsal bone was locked in the condylar groove of the medial first phalanx. The subluxation was reduced, the joint carefully debrided and irrigated, and the torn ligament was replaced with a synthetic prosthesis which was fixed with titanium alloy staples. One year after surgery, the joint was slightly swollen but the cow was not lame.