Hugo Schmökel

Evidensia Academy · Orthopedic and spine surgery

Skeletal disease may hamper the behavior of large predators both living and extinct. We investigated the prevalence of osteochondrosis dissecans (OCD), a developmental bone disease affecting the joints, in two Ice Age predators: the saber-toothed cat Smilodon fatalis and dire wolf Aenocyon dirus. As published cases in modern Felidae and wild Canida...

Objective The aim of this study was to review and describe cases of thoracolumbar (TL) hydrated nucleus pulposus extrusion (HNPE) diagnosed with magnetic resonance imaging and surgery, and compare them to cases of cervical (C) HNPE. Study Design Retrospective, single-center study. Results Thirty-six dogs met the inclusion criteria. Fifteen cases we...

Objectives To evaluate the effectiveness and complication rate of a 1.5- and 2.0-mm titanium locking plate for the treatment of radial and ulnar fractures in small dog breeds and cats without peri-operative antibiotic prophylaxis in a prospective case series. Materials and Methods Medical records and radiographs of closed radial and ulnar fracture...

An 11 mo old intact female German shepherd dog was presented with a 1 day history of vomiting, abdominal pain, and lethargy. A complete gallbladder torsion with secondary bile leakage was diagnosed during exploratory laparotomy. The dog underwent cholecystectomy at the clearly demarcated border of the viable cystic duct and recovered with no compli...

A six-year-old American Staffordshire terrier with proprioceptive deficits of the right thoracic and pelvic limb was referred for further work-up. Cervical computed tomography (CT) and magnetic resonance imaging (MRI) revealed a triple cervical canal stenosis with dorsal spinal cord compression and concomitant compressive myelopathy caused by verte...

OBJECTIVE To estimate the times required for dogs to regain micturition and ambulation following surgical treatment for thoracolumbar Hansen type I intervertebral disk extrusion (IVDE) and determine whether these variables were associated with preoperative modified Frankel score (MFS). DESIGN Retrospective case series with nested cohort study. ANIM...

Objective The aim of this study was to retrospectively review the surgical site infection (SSI) rate in dogs undergoing laminectomies without perioperative antibiotics, and compare those data with the expected infection rate for clean surgical wounds in dogs undergoing similar procedures. Methods This was a retrospective single-centre study compose...

An approach using a complete cranial iliac osteotomy (CCIO) to access the lumbosacral (LS) foramen in dogs from lateral was developed using cadavers and applied in a clinical patient with degenerative lumbosacral stenosis (DLSS). The foraminal enlargement in the cadavers and the patient was documented on postoperative CT scans. The preoperative CT...

Three dogs were presented with lumbosacral hyperesthesia. Computerized tomography scans were performed in all the cases, and magnetic resonance imaging was also performed in cases 1 and 3. There was intervertebral disc (IVD) protrusion causing nerve root compression and epidural gas accumulation in all the three cases. The gas-filled cystic structu...

Objective: To assess the perioperative complications and the outcome when treating small-breed dogs with cranial cruciate ligament insufficiency with tibial tuberosity advancement using the TTA Rapid implant. Materials and methods: 40 dogs (48 stifles) with cranial cruciate ligament insufficiency and body weight of 15 kg or less. Diagnosis was c...

Case summary A 10-month-old, male castrated, domestic shorthair cat was presented with fast-progressing ataxia of the pelvic limbs. MRI and CT were performed, revealing a bony proliferation at T11, with mass effect and laterodorsal compression of the spinal cord. After hemilaminectomy and the removal of the bony mass, the cat recovered uneventfully...

Three German Shepherd Dogs that were presented for investigation of chronic unilateral hindlimb lameness and pain in the lumbosacral region were diagnosed with an intraspinal, extradural synovial cyst and reactive fibrosis protruding into the foramen of the lumbosacral articulation using magnetic resonance imaging and histology. This extradural mas...

Comparison of two methods for evaluation of anatomical parameters of elbow joints in Bernese Mountain Dogs. Radiographic analysis. Nine hundred and thirty-one radiographs of elbow joints from 305 Bernese Mountain Dogs. The angles OL, PA, RA and UL were measured according to the Mues method and the Radius of the humeral condyle, Opening angle beta,...

In medicine N-methylpyrrolidone (NMP) has a long track record as constituent in FDA approved medical devices and thus can be considered as safe and biological inactive small chemical. In the present study we report on the newly discovered pharmaceutical properties of NMP as it enhances bone regeneration in a rabbit calvarial defect model in vivo. A...

In medicine, N-methyl pyrrolidone (NMP) has a long track record as a constituent in medical devices approved by the Food and Drug Administration and thus can be considered as a safe and biologically inactive small chemical. In the present study, we report on the newly discovered pharmaceutical property of NMP in enhancing bone regeneration in a rab...

To describe the perioperative complications and the six weeks and eight to 12 months outcome of cases of canine cranial cruciate ligament damage treated with a tibial tuberosity advancement. The medical records including the six weeks' postoperative re-evaluation and radiographs of dogs with a tibial tuberosity advancement (70 operated stifles) wer...

We here present an evaluation of the carrier performance of nanoparticles that are biofunctional, i.e. derivatized to provide a controlled biological activity, and environmentally responsive, since they respond to the presence of oxidants. In particular, we focus on the possibilities (a) to make the nanoparticles detectable and (b) to control their...

Bioresorbable scaffolds made of poly(L-lactic acid) (PLA) obtained by supercritical gas foaming were recently described as suitable for tissue engineering, portraying biocompatibility with primary osteoblasts in vitro and interesting mechanical properties when reinforced with ceramics. The behavior of such constructs remained to be evaluated in viv...

Activation of vascular endothelial growth factor (VEGF) receptor-3 (VEGFR-3) by VEGF-C initiates lymphangiogenesis by promoting lymphatic proliferation and migration. However, it is unclear whether VEGFR-3 signaling is required beyond these initial stages, namely during the organization of new lymphatic endothelial cells (LECs) into functional capi...

The aim of the here described case series was to develop and evaluate the minimally invasive percutaneous osteosynthesis for the plate fixation of tibial fractures in dogs and cats. Six dogs and four cats with shaft fractures of the tibia were treated using minimally invasive percutaneous osteosynthesis. Follow-up radiographs four to six weeks afte...

We present here the biological performance in supporting tissue regeneration of hybrid hydrogels consisting of genetically engineered protein polymers that carry specific features of the natural extracellular matrix, cross-linked with reactive poly(ethylene glycol) (PEG). Specifically, the protein polymers contain the cell adhesion motif RGD, which...

Little is known about the magnetic resonance imaging (MRI) appearance of canine meniscal lesions. The aim of this study is to describe the MR appearance of meniscal lesions in dogs with experimentally induced cranial cruciate ligament (CCL) deficiency. The pilot study revealed dogs weighing approximately 10 kg to be too small for meniscal evaluatio...

Delivery of biodegradable nanoparticles to antigen-presenting cells (APCs), specifically dendritic cells (DCs), has potential for immunotherapy. This study investigates the delivery of 20, 45, and 100nm diameter poly(ethylene glycol)-stabilized poly(propylene sulfide) (PPS) nanoparticles to DCs in the lymph nodes. These nanoparticles consist of a c...

The aim of the present study was (1) to test whether or not platelet-rich plasma (PRP) or commercially available fibrin can increase bone regeneration compared with non-treated defects and (2) to test whether or not PRP or fibrin increases bone regeneration when used as a delivery system for recombinant human bone morphogenetic protein-2 (rhBMP-2)....

IL-1 and TNF are important proinflammatory cytokines implicated in both antimicrobial host defense and pathogenesis of diseases with an immune-mediated and/or inflammatory component. Respective studies in the dog have been hampered by the unavailability of reagents allowing the specific measurement of canine cytokine proteins and the effect of cani...

Diagnosis of osteoarthritis (OA) is based upon the clinical orthopaedic examination and the radiographic assessment, both of which can be non-specific and insensitive in early joint disease. The aim of our study was to investigate if there is an increase in serum levels of C-reactive protein (CRP) in degenerative joint disease (DJD) and if CRP coul...

Most growth factors naturally involved in development and regeneration demonstrate strong binding to the extracellular matrix and are retained there until being locally mobilized by cells. In spite of this feedback between cell activity and growth factor mobilization in the extracellular matrix, this approach has not been extensively explored in th...

To test a non-glycosylated recombinant human bone morphogenetic protein-2 (ngly-rhBMP-2)/fibrin composite, which has been shown experimentally to enhance healing of bone defects in rodents, in a clinical case series of dogs and cats undergoing treatment for fracture non-unions and arthrodesis. A ngly-rhBMP-2/fibrin composite was applied in 41 sites...

Arthrodesis is often necessary as the definitive treatment of degenerative joint disease. In the horse, the extended bone healing period presents particular challenges and requires long rest periods. In the last years bone growth factors were isolated, which then have been shown to accelerate bone healing after arthrodesis in dogs. This report docu...

Five cats with large, distal extremity abrasion wounds were treated with an autogenous, full-thickness, mesh skin graft. Survival of the mesh grafts in all five cats was considered between 90 and 100%. Successful grafting requires asepsis, an adequately prepared recipient bed consisting of healthy granulation tissue, proper harvesting and preparati...

Cell interactions with the extracellular matrix play important roles in guiding tissue morphogenesis. The matrix stimulates cells to influence such things as differentiation and the cells actively remodel the matrix via local proteolytic activity. We have designed synthetic hydrogel networks that participate in this interplay: They signal cells via...

A novel form of recombinant human bone morphogenetic protein-2 (BMP-2) was explored for effective incorporation and long-term retention into fibrin ingrowth matrices. The solubility of native BMP-2 is greatly dependent on its glycosylation. To enhance retention of BMP-2 in fibrin matrices, a nonglycosylated form (nglBMP-2), which is less soluble th...

An open multi-centre veterinary clinical trial, comparing conditions before and after treatment with a herbal dietary supplement consisting of a natural resin extract of Boswellia serrata, was conducted by 10 practicing veterinarians in Switzerland. This traditional plant-based supplement is known for its anti-rheumatic and anti-inflammatory proper...

To report the results of the treatment of nonunions with nonglycosylated recombinant human bone morphogenetic protein-2 (nglBMP-2) delivered from a designed fibrin matrix. Experimental trial in rodents and prospective clinical study in dogs and cats with nonunion fractures. Twenty adult female, albino, Sprague-Dawley rats; 8 client-owned cats and d...

The tibial plateau angles (TPA) of dogs with andwithout cranial cruciate ligament (CrCL) injuries wereevaluated and further compared to the TPAs of dogsfrom a previous population and of wolves. Similar TPAmeasurements were found in all groups, suggestingthat any possible changes in breeding practises,breed preferences, nutrition or other factors ha...

Tarsal injuries occur commonly in the cat and the dog, often due to motor vehicle accidents. In two cases a talocalcaneocentral luxation was associated with lateral talocrural instability. The surgical fixation of the talocalcaneocentral luxation, employing Kirschner pins in a cat and a DC plate in a dog, together with stabilisation of the lateral...

The tibial plateau angles (TPA) of dogs with and without cranial cruciate ligament (CrCL) injuries were evaluated and further compared to the TPAs of dogs from a previous population and of wolves. Similar TPA measurements were found in all groups, suggesting that any possible changes in breeding practises, breed preferences, nutrition or other fact...

Local, controlled induction of angiogenesis remains a challenge that limits tissue engineering approaches to replace or restore diseased tissues. We present a new class of bioactive synthetic hydrogel matrices based on poly(ethylene glycol) (PEG) and synthetic peptides that exploits the activity of vascular endothelial growth factor (VEGF) alongsid...

Heterotopic ossification is a frequent complication in patients who have suffered head and neck traumas or have undergone total hip replacement. In this report, stable folding variants of the natural occurring osteoinductive BMPs were shown to act as inhibitors for heterotopic ossification. The most effective BMP folding variant construct performed...

A trend toward minimally invasive procedures in the treatment of fractures in human patients is apparent in recent publications. Percutaneous plating is one method of fracture fixation, conceived to minimise soft tissue damage and preserve soft tissue and bone vascularity. The use of fewer screws, in longer bridging plates, is also a relatively new...

We have engineered synthetic poly(ethylene glycol) (PEG)-based hydrogels as cell-ingrowth matrices for in situ bone regeneration. These networks contain a combination of pendant oligopeptide ligands for cell adhesion (RGDSP) and substrates for matrix metalloproteinase (MMP) as linkers between PEG chains. Primary human fibroblasts were shown to migr...

Endoscopic ultrasound was developed initially in humans to overcome limitations of conventional ultrasound in examining certain internal organs due to intervening bone or air-filled structures. Endoscopic ultrasound has been used most widely in investigation of the gastrointestinal tract in humans, but many intrathoracic applications as well as end...

Synthetic hydrogels have been molecularly engineered to mimic the invasive characteristics of native provisional extracellular matrices: a combination of integrin-binding sites and substrates for matrix metalloproteinases (MMP) was required to render the networks degradable and invasive by cells via cell-secreted MMPs. Degradation of gels was engin...

The purpose of this study was to assess radiographically the healing process in dogs which had undergone dorsal pancarpal arthrodesis with autologous cancellous bone grafting. The medical records of 17 dogs that had undergone dorsal pancarpal arthrodesis with complication-free dynamic compression plate fixation were reviewed. Postoperative healing...

Graft copolymers were designed that could spontaneously bind to biological surfaces and block subsequent recognition and adhesion at those surfaces. Phenylboronic acid (PBA) moieties in the polymer backbone provided binding to surfaces, forming reversible covalent complexes with cis-diols found in many biological molecules. Pendant poly(ethylene gl...

Meniscal injuries are currently under much clinical investigation. With regard to tissue engineering strategies for meniscal repair or replacement, the direct measurement of forces applied on the meniscus, during range of motion, could provide important information. This in vitro study using canine cadaver limbs evaluated the possibility of measuri...

The surgical treatment of talocrural luxation in nine cats was evaluated. Stabilisation of the joint was achieved by internal fixation of fractures and ligament replacement. A splint provided external support in eight cats and an external fixator was used in one. The support remained in place for three to seven weeks in five cats (group #1) but is...

The enzyme activities of alkaline phosphatase (AP), aspartate aminotransferase (AAT) and lactate dehydrogenase (LDH) were analysed in synovial fluid of normal and pathologic canine joints. The activities of the AP and the AAT overlapped too much in normal and pathologic joints to be a helpful clinical test. LDH activity in synovial fluid of joints...

In a seven months old German Shepherd dog an elbow dysplasia was diagnosed with a step between the radius and the coronoid processes of the ulna, a sclerosis of the trochlear notch because of an overloading of the medial coronoid process and a subluxation of the ulna. A midshaft ulnaostectomy was performed and stabilised with an external fixator wi...

The combination of a fracture of the proximal tibia (Salter-Harris type II) with an avulsion of the tibial tuberosity is a rare injury in the growing dog. Internal fixation of the tibial plateau with K-wires, in some cases combined with a tension band wire for the avulsed tuberosity, resulted in complete healing. There is the possibility of develop...

ABSTRACTA retrospective study of 21 surgically treated feline tarsal injuries showed that the degree of soft tissue trauma was the main parameter influencing the long term outcome. Generally, tarsal fractures could be successfully reconstructed and managed by internal fixation. Simple rupture of a collateral ligament could be sutured or treated wit...