Clinical relevance of positive intraoperative bacterial culture in tibial plateau leveling osteotomy in dogs: a retrospective study.

BACKGROUND: Tibial plateau leveling osteotomy (TPLO) belongs to the most frequently used surgical method for the treatment of cranial cruciate ligament rupture in dogs. Surgical site infection (SSI) is one of the possible postoperative complications. The aim of this study was to evaluate the diagnostic value of intraoperative bacterial culture as a tool for the detection of intraoperative bacterial contamination progressing to infection development in canine TPLO. Electronic patient records from dogs who underwent TPLO between January 2018 to December 2020 were retrospectively reviewed. Intraoperative bacterial culture results, used antimicrobial drugs and presence of SSI were recorded. RESULTS: Ninety-eight dogs were included in the study. SSI rate was 10.2%. All dogs who developed SSI (n = 10) had negative intraoperative bacterial cultures. None of the dogs with positive intraoperative bacterial culture (n = 6) developed SSI. The most cultured bacteria causing SSI was Staphylococcus pseudintermedius (n = 4). CONCLUSIONS: Intraoperative bacterial culture in dogs undergoing TPLO is not suitable as a predictor of surgical site infection.

Dogs with Bilateral Medial Coronoid Disease Can Be Clinically Sound after Unilateral Arthroscopic Fragment Removal-Preliminary Study.

The purpose of this study was to assess the outcome of dogs with bilateral medial coronoid disease (MCD) treated with arthroscopic intervention for the clinically more severely affected side and conservative management for the contralateral side. The medical records of dogs with bilateral medial coronoid disease diagnosed using computed tomography (CT) and treated using arthroscopic intervention on one elbow and conservative management on the other elbow were retrospectively reviewed. The outcome evaluation included clinical re-examination; follow-up radiographic-visible osteophytic lesions; as well as sclerotic changes and Liverpool osteoarthritis in a dogs questionnaire. Data from 48 clinically affected elbow joints (24 dogs) with bilateral MCD diagnosed using CT were included. Every dog underwent arthroscopic intervention on the elbow joint, which was clinically more severely affected, and the other side was treated with conservative management. A fragment of the medial coronoid was diagnosed using CT in all elbows, whereas 19 elbows (39.4%) showed a dislocation of the fragment and the other 29 elbows (60.4%) did not. There are no findings regarding the radioulnar Incongruence. Initially, 86% of all radiographs had the same degree of osteophytes. At the time of follow-up, the arthroscopic-treated limbs had more severe radiological changes in comparison to the conservatively treated limbs. Lameness improved after arthroscopic therapy in walking. The conservative group showed a largely unchanged gait pattern. Radiological changes do not necessarily reflect the severity of clinical signs. Arthroscopic intervention showed an improvement of the clinical gait pattern, even though the radiographic changes worsened.

Novel approach for the treatment of canine elbow hygroma with extracorporeal shockwaves.

A hygroma is a fluid filled cavity, which appears due to repetitive traumata over bony prominences. For canine elbow hygroma there is no satisfactory treatment option available. Small hygromas should not be treated at all. Larger hygromas that restrict the dog in daily life, are infected, painful, or ulcerated should be treated surgically with drainage or total excision. Surgical treatment of hygromas results in long rehabilitation times and is associated with a high complication rate. Extracorporeal shockwave therapy (ESWT) is widely used in human and veterinary rehabilitation medicine since several years. Even the mechanisms of action are not fully understood it has a wide range of indications. ESWT provides anti-inflammatory effects, promotes microcirculation, and is used for pain relief. In this case series of 4 consecutive cases in 3 dogs we treated hygromas with extracorporeal shockwaves each for 3 to 6 times usually on a weekly basis. All hygromas regressed completely and no complications were noted. Overall ESWT seems to provide a safe, easy-to-use, as well as cost-effective alternative treatment option for canine elbow hygroma.

Economic Considerations on Costs and Pricing of Two Surgical Techniques for Treating Cranial Cruciate Disease in Dogs.

In surgical treatment of cranial cruciate ligament disease in dogs, Tibial Plateau Levelling Osteotomy (TPLO) and Tibial Tuberosity Advancement (TTA) are commonly established procedures and have proven effective in restoring limb function. Unlike clinical outcome, economic aspects have not been studied as extensively. However, the surgical intervention poses an enormous financial burden on patients' owners. In a veterinary practice setting, this study compares prices for TPLO and TTA and examines prices differences as well as potential cost drivers. Charges for veterinary treatments are based on the Gebührenordnung für Tierärztinnen und Tierärzte (GOT), which is mandatory for veterinarians in Germany but allows a certain range in billing. This study found that TPLO is charged at a higher price than TTA; however, this might not cover the additional costs of this procedure. The price is also associated with weight, heavier dogs being more expensive. The underlying strategies for pricing decisions may be based on costs, as efforts for TPLO and heavier dogs are higher in terms of a prolonged surgical time, the number of staff involved and in surgeons' training. Price setting may also be based on a quality promise, suggesting better clinical outcome in a more expensive procedure. Future investigations should involve economic considerations and consider cost-effectiveness analysis when evaluating surgical treatment options.

Comparative evaluation of radiographic and computed tomographic findings in dogs with bilateral medial coronoid disease (MCD) presenting with unilateral forelimb lameness.

OBJECTIVES: The purpose of this study was to compare the radiographic and computed tomographic (CT) findings of dogs with diagnosed bilateral medial coronoid disease, which showed clinically only unilateral lameness of the forelimbs. MATERIALS AND METHODS: Medical records, including radiographs and CT images of dogs with diagnosed bilateral MCD showing only a unilateral forelimb lameness clinically were reviewed retrospectively. Depending on the gait of each dog we established two groups to investigate their radiographs and CT data comparatively. Group I: affected non-lame limb. Group II: affected lame limb. Several evaluation systems were used to assess which factors are important for clinical decision making and a patient tailored therapeutic plan. RESULTS: Data from 84 affected elbow joints (42 dogs) diagnosed with MCD by computed tomography were included. Both the radiological and the CT analysis showed that there are significant differences between Groups I and II. Group I had a lower modified International Elbow Working Group Score (IEWG), the values of the Trochlear notch sclerosis were only slightly deviated, and this group showed less often a dislocation of the fragment compared to group II. Furthermore, the size of the fragment (both the median and the mean value) of the forelimbs from group II was almost twice as big as the one from group I. The following sizes of the fragments were calculated (group I versus (vs.) group II)-median: 0.09 cm2 vs. 0.16 cm2, mean value: 0.112 cm2 vs. 0.202 cm2. It could be shown that a larger fragment is more likely to dislocate than a smaller one. CLINICAL SIGNIFICANCE: This study provides some evidence towards a better understanding of which diagnostic parameters and findings might be important in clinical decision making. Nevertheless, a "decision tree" for the correct therapy of MCD could not be determined in this study.

Characterization of Human, Ovine and Porcine Mesenchymal Stem Cells from Bone Marrow: Critical In Vitro Comparison with Regard to Humans.

For research and clinical use of stem cells, a suitable animal model is necessary. Hence, the aim of this study was to compare human-bone-marrow-derived mesenchymal stem cells (hBMSCs) with those from sheep (oBMSCs) and pigs (pBMSCs). The cells from these three species were examined for their self-renewal potential; proliferation potential; adhesion and migration capacity; adipogenic, osteogenic and chondrogenic differentiation potential; and cell morphology. There was no significant difference between hBMSCs and pBMSCs in terms of self-renewal potential or growth potential. The oBMSCs exhibited a significantly higher doubling time than hBMSCs from passage 7. The migration assay showed significant differences between hBMSCs and pBMSCs and oBMSCs-up to 30 min, hBMSCs were faster than both types and after 60 min faster than pBMSCs. In the adhesion assay, hBMSCs were significantly better than oBMSCs and pBMSCs. When differentiating in the direction of osteogenesis, oBMSCs and pBMSCs have shown a clearer osteogenic potential. In all three species, adipogenesis could only be evaluated qualitatively. The chondrogenic differentiation was successful in hBMSCs and pBMSCs in contrast to oBMSCs. It is also important to note that the cell size of pBMSCs was significantly smaller compared to hBMSCs. Finally, it can be concluded that further comparative studies are needed to draw a clear comparison between hBMSCs and pBMSCs/oBMSCs.

Surgical treatment of cranial cruciate ligament disease in dogs using Tibial Plateau Leveling Osteotomy or Tibial Tuberosity Advancement-A systematic review with a meta-analytic approach.

Tibial Plateau Leveling Osteotomy (TPLO) or Tibial Tuberosity Advancement (TTA) are commonly used surgical techniques for correction of cranial cruciate ligament (CCL) rupture in dogs. This systematic review aims to investigate whether one technique is superior to the other. Seventy-two studies on surgical management of CCL rupture have been identified and evaluated in regard of subjective and objective gait analysis criteria, development of osteoarthritis (OA), thigh circumference measurements, goniometry, joint stability, pain and complication rates. Almost half (47.2 %) of the studies were considered of low quality of evidence, leading to high heterogeneity in quality among studies; this posed a major limitation for an evidence-based systematic review of both surgical techniques. Out of 72 studies, there were only eleven blinded randomized clinical trials, of which five were rated with a low overall risk of bias. However, both techniques were considered to be successful management options. Subjective and objective gait analysis revealed no lameness at long-term evaluation for the majority of the patients. However, it appeared that TTA lead to better OA scores up to 6 months postoperatively, while TPLO had a lower rate of surgical site infections. In summary, no method can be clearly preferred, as most of the study evaluated were subpar. Studies with a high level of evidence are therefore urgently needed for such a common surgical procedure.

Performing a Three-Dimensional Finite Element Analysis to Simulate and Quantify the Contact Pressure in the Canine Elbow Joint: A Pilot Study.

OBJECTIVE: The aim of this study was to measure surface pressures and force distribution on radius and ulna in healthy and dysplastic elbow joints in different positions using the finite element analysis (FEA). STUDY DESIGN: FEA was performed on computed tomographic data of healthy and fragmented coronoid process diseased elbow joints of Labrador Retrievers. It considered the articular cartilage, collateral ligaments, triceps and biceps muscle. The analysis of each joint was performed in four positions (standing position: 145 degrees and three positions of the stance phase of gait: beginning: 115 degrees, middle: 110 degrees, end: 145 degrees joint angle) in consideration of different ground reaction forces (standing: 88.3 N; stance phase of gait: 182.5 N). RESULTS: Mean values of total force of 317.5 N (standing), 590.7 N (beginning), 330.9 N (middle) and 730.9 N (end) were measured. The percentual force distribution resulted in a total of 49.56 ± 26.58% on the ulna with a very inhomogeneous distribution. A significant difference was detected between the positions 'standing' and 'end' (p = 0.0497) regardless of the joint condition. In some FEA results, visual assessment of the surface pressures indicated an increase in pressure in the region of the medial compartment without a uniform pattern. An increase in pressure resulted in an area increase in the pressure marks on the joint surface and measurable pressure was increased at a larger joint angle. CLINICAL SIGNIFICANCE: FEA can provide information about the transmission of force in the joint. Prior to the use of FEA in scientific clinical research for the simulation of force, further model improvements are necessary.

Case Report: Unable to Jump Like a Kangaroo Due to Myositis Ossificans Circumscripta.

A male 10-year-old captive red kangaroo (Macropus rufus) was presented with a chronic progressive pelvic limb lameness and reluctance to jump. The general examination revealed a palpable induration of the lumbar epaxial muscles. Magnetic resonance imaging performed under general anesthesia revealed bilateral almost symmetric, well-circumscribed mass lesions in superficial erector spinae muscles. The lesions had irregular to multilobulated appearance with hyper-, hypo-, and isointense areas in T2- and T1-weighted (w) sequences without contrast enhancement. On computed tomography, a peripheral rim of mineralization was apparent. Histopathological analysis of a muscle biopsy showed osseous trabeculae with rare clusters of chondrocytes indicating metaplasia of muscle tissue to bone. No indications of inflammation or malignancy were visible. The clinical, histopathological, and imaging workup of this case was consistent with myositis ossificans circumscripta. This disorder is particularly well-known among human professional athletes such as basketball players, where excessive, chronic-repetitive force or blunt trauma causes microtrauma to the musculature. Metaplasia of muscle tissue due to abnormal regeneration processes causes heterotopic ossification. The kangaroo's clinical signs improved with cyto-reductive surgery, cage rest, weight reduction, and meloxicam without further relapse.

Ex Vivo Evaluation of the Cranial Tibial Artery and Its Compression through Fragment Rotation during Tibia Plateau Levelling Osteotomy: An Angiographic Three-Dimensional Reconstruction.

OBJECTIVE: To illustrate the arterial vascularity of the proximal tibia three-dimensionally and to evaluate the impact of fragment rotation on the cranial tibial artery by tibia plateau levelling osteotomy (TPLO). METHODS: Radiographic angiography and computed tomography (CT) were performed on 12 pelvic limbs from six large-breed canine cadavers before and after TPLO. Three-dimensional (3D) models of the stifle, including osseous and vascular structures, were obtained, and the integrity of the cranial tibial artery was assessed. Post-TPLO CT images were used to analyze compression of the cranial tibial artery by the rotated fragment. RESULTS: The uncompressed cranial tibial artery caliber, measured proximally and distally to the osteotomy, was 9.52 mm2 (6.07-18.90 mm2). In all adequately rotated fragments, the mean caliber of the artery on the level of the osteotomy was 1.57 mm2 (0.89-2.93 mm2) after TPLO. This represented a significant decrease of approximately 81%. Only slight cross-sectional area decrease (8.8%) was seen in one limb, which was revealed to have insufficient fragment rotation (2.83 mm). Another limb only showed signs of stretching of the artery (31.51%), which was under-rotated and medially displaced. Pre-TPLO 3D reconstructions were mainly consistent with previous anatomic studies except for the distance between tibial cortex and cranial tibial artery, which appeared closer. CONCLUSION: Sufficient fragment rotation leads to compression of the cranial tibial artery. Intraoperative hemorrhage can be caused by laceration of the main cranial tibial artery or by multiple small branches reaching craniolaterally.

The effect of steam sterilization on different 3D printable materials for surgical use in veterinary medicine.

BACKGROUND: Different 3D-printed materials polyactic acid (PLA), polyamide (PA), polycarbonates (PC), acrylonitrile butadiene styrene (ABS) and GreenTEC Pro®I have been considered for surgical templates, but there is a sparity of data about how these materials are affected by steam sterilization. The aim of the current study was to test if and how these materials change morphologically when high temperature, pressure and humidity are applied during the steam sterilization process. The overall aim is to create patient-specific sawing templates for performing corrective osteotomies. After the designing process, test-specimens with five different materials: PLA, PC, ABS, PA and GreenTEC Pro® were 3D-printed in two filling grades (30 and 100%). The FDM method was used for printing. After 3D-printing, the test-specimens were steam sterilized with a standard program lasting 20 min, at a temperature of 121 °C and a pressure of 2-3 bar. In order to measure the deviation of the printed model, we measured the individual test-specimens before and after steam sterilization using a sliding gauge. RESULTS: PC, PA and ABS showed great morphological deviations from the template after 3D-printing and steam sterilization (> 1%) respectively. ABS proved unsuitable for steam sterilization. PLA and GreenTEC Pro® demonstrated fewer morphological deviations both before and after sterilization. Therefore, we decided to perform a second test just with PLA and Green-TEC Pro® to find out which material has the highest stability and is probably able to be used for clinical application. The smallest deviations were found with the GreenTEC Pro® solid body. After autoclaving, the specimens showed a deviation from the planned body and remained below the 1% limit. CONCLUSION: Steam sterilization causes morphological deviations in 3D printed objects. GreenTEC Pro® seems to be a suitable material for clinical use, not only for intraoperative use, but also for precise modeling. Microbiological examination, as well as biomechanical tests, should be performed to further assess whether intraoperative use is possible.

Development of a three-dimensional computer model of the canine pelvic limb including cruciate ligaments to simulate movement.

Gait analysis as subjective visual assessment forms the foundation of the veterinarian's lameness examination. Pelvic limb lameness is frequently seen in dogs and the stifle joint with its cruciate ligaments, is a main cause of lameness due to cruciate ligament deficiency. In this study, we developed an open-source three-dimensional musculoskeletal pelvic limb model of a 30 kg Labrador Retriever including cruciate ligaments, simulating the gait cycle of the walking movement with the open-source programs NMSBuilder (Institutio Ortopedico Rizzoli, Bologna, Italy) and OpenSim (National Center for Simulation in Rehabilitation Research (NCSRR), Stanford, CA, USA). The computer model generated muscle activations based on motion data. The computed activations were similar to experimental electromyogram data. Highest joint torque was in extension/flexion in the stifle joint at 54 Nm at 14% of the gait cycle with cruciate ligaments. Highest stifle joint reaction force was 408 N at 16% of the gait cycle and was reduced after adding cruciate ligaments. Especially the cranial cruciate ligament loads up to 102 N (34% body weight). Cranial cruciate ligament forces increase with stifle extension and decrease with stifle flexion. On the contrary, the caudal cruciate ligament loads up to 27 N (9% body weight) during the swing phase with a flexed stifle joint. The model was validated with electromyogram data. The model's predictions are plausible because joint torques and forces match the applied ground reaction forces in curve progression and in timing. This model forms a basis for further investigations into stifle surgery after cruciate ligament deficiency.

Treatment of the Clinical Symptoms of Osteoarthritis in the Elbow Joints of Dogs Using Nuclear Magnetic Resonance Therapy: A Randomized, Double-Blinded Trial.

Objectives: To evaluate the effects of nuclear magnetic resonance therapy (MBST®) on the clinical symptoms of osteoarthritis (OA) in the elbow joints of dogs. Methods: In this double-blind study, 28 dogs with lameness caused by OA in the elbow joint were randomly allocated to two groups: 14 dogs received nuclear magnetic resonance (NMR) therapy [treatment group (TG)], and 14 dogs received a placebo [placebo group (PG)] over a period of 7 consecutive days. Visual and objective gait analyses were performed before treatment (M1) and at 3 (M2) and 6 months (M3) after treatment. At M2 and M3 Symmetry indices (SI) of the peak vertical force (PVFz) and the vertical impulse (IFz), lameness scores, and pain scores were compared with their values at M1 to calculate the overall treatment effectiveness (OTE) score. We also documented additional pain medication and medical physiotherapy during the time of study. Finally, we measured the range of motion (ROM) in order to evaluate the functional development of the joint. Results: The median OTE score of dogs in the TG indicates no change after 3 month and was improved after 6 months of treatment. There was an improvement of the median OTE score of dogs in the PG after 3 months of treatment. Further, the OTE scores of dogs in the PG were actually worse after 6 months. Nevertheless, there were no significance differences in SIPVFz, SIIFz, ROM, and lameness- and pain scores between the TG and PG at M1, M2, and M3. When considering all collected parameters (excluding the ROM) to calculate the OTE, no significant difference between groups was measurable for the OTE. Conclusion: There was a positive effect of NMR therapy (MBST®) on the treatment of OA in dogs. However, future studies should investigate the mechanisms underlying NMR therapy and the pathophysiology of OA to provide optimal treatments for patients. Clinical Significance: Our results demonstrated that the response to NMR treatment was individualized for each dog. As an integral way of treating dogs with chronic OA, NMR therapy may be an alternative therapeutic approach to support traditional medications.

Diagnosis and treatment of infraspinatus tendon-bursa ossification in a Eurasian Dog.

A 4-year-old male Eurasian Dog presented at our veterinary clinic with a history of perpetual forelimb lameness in both thoracic limbs. In the clinical exploration, direct pressure over the infraspinatus tendon of insertion caused pain in both thoracic forelimbs and a firm band-like structure was palpable. No improvement was observed after treatment with rest, non-steroidal anti-inflammatory drugs and an intralesional injection of a long-acting glucocorticoid. Radiographic examination, ultrasonographic exploration and computed tomography were performed, identifying ossified structures lateral to the proximal humerus and an irregular roughened periosteum at the insertion and tendon of the infraspinatus muscle on both sides. There were more distinct alterations on the right thoracic limb. The imaging results led to a diagnosis of an infraspinatus tendon-bursa ossification accompanied by a chronic tendinopathy/tendovaginitis, accentuated on the right side. The dog was subjected to physiotherapy and autologous conditioned plasma (ACP) was injected into the insertion of the infraspinatus muscle of both thoracic limbs. After 5 months of physiotherapy and two injections of ACP with an interval of one week in both forelimbs, the dog showed no signs of lameness. This case report describes the diagnosis and management of infraspinatus tendon-bursa ossification in a Eurasian Dog. To the authors' knowledge, this condition has previously not been described in this breed of dog.

Comparison of two cold compression therapy protocols after tibial plateau leveling osteotomy in dogs.

OBJECTIVE: To evaluate two different protocols of cold compression therapy (CCT) for pain management and functional recovery in dogs undergoing tibial plateau leveling osteotomy (TPLO). MATERIAL AND METHODS: A total of 27 adult dogs (n = 30 stifles; staged bilateral procedures: n = 3) undergoing routine TPLO were randomly allocated to three groups (n = 10/group). Dogs of group I received CCT once before and immediately after surgery. In dogs of group II CCT was performed postoperatively four times at 6-hour intervals. Dogs of the control group did not receive CCT. Circumference of the stifle joint and the following pain-related parameters were measured by a single blinded observer before surgery and 1, 10 and 42 days after surgery: stifle joint range of motion (ROM), subjective degree of lameness, and score of a modified Glasgow Pain Scale (GPS). RESULTS: Both CCT groups showed significantly greater ROM and lower GPS scores 24 hours after surgery compared to the control group. Ten days after surgery there was a significantly lower degree of lameness in both CCT groups compared to the control group. Fourty-two days after surgery a significantly greater ROM was observed in both CCT groups compared to the control group. Group II also showed a significant improvement in the degree of lameness and GPS. There were no significant differences in any of the parameters between the two CCT groups at any time point. CONCLUSION: CCT applied preoperatively and immediately postoperatively showed similar short- and long-term beneficial results compared to a previously established protocol of applying CCT four times postoperatively. This protocol may be more suitable for practical use. CLINICAL SIGNIFICANCE: The reported data can be used to establish the new protocol of CCT in a clinical surrounding and to support postoperative rehabilitation of the canine patient.

Clinical, radiographic, and magnetic resonance imaging findings of gastrocnemius musculotendinopathy in various dog breeds.

OBJECTIVES: To describe clinical, radiographic, and magnetic resonance imaging (MRI) findings in 16 dogs diagnosed with gastrocnemius musculotendinopathy. METHODS: Retrospective evaluation of medical records, radiographs, and MRI results, as well as follow-up completed by telephone questionnaire. RESULTS: Most dogs had chronic hindlimb lameness with no history of trauma or athletic activities. Clinical examination revealed signs of pain on palpation without stifle joint instability. Seven dogs had radiographic signs of osteophyte formation on the lateral fabella. Magnetic resonance imaging revealed T2 hyperintensity and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. Changes were found in the lateral and medial heads of the gastrocnemius. Conservative treatment resulted in return to full function in 11 dogs. Two dogs showed partial restoration of normal function, one dog showed no improvement. Two dogs were lost to follow-up. CLINICAL SIGNIFICANCE: Gastrocnemius musculotendinopathy is a potential cause of chronic hindlimb lameness in medium to large breed dogs. A history of athletic activity must not necessarily be present. Magnetic resonance imaging shows signal changes and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. A combination of T1 pre- and post-contrast administration and T2 weighted sequences completed by a fat-suppressed sequence in the sagittal plane are well-suited for diagnosis. Conservative treatment generally results in return to normal function.

Radiographic location of the origin and insertion of the canine medial glenohumeral ligament. / Radiographische Lokalisation der Ansatz- und Ursprungspunkte des medialen glenohumeralen Bandes beim Hund.

OBJECTIVE: To define the radiographic origin and insertion of the canine medial glenohumeral ligament (MGHL) at the scapula and the humerus of dogs as radiographic aim points for the surgical ligament reconstruction. MATERIAL AND METHODS: The forelimbs (n = 20) from 10 adult, orthopaedically unaffected dogs (> 20 kg body weight) were used. Radiopaque markers (1 mm steel bullet) were placed into the visual origin and insertion of the MGHL. Finally, virtual digital radiographs were produced in medio-lateral and cranio-caudal projection and the location of the origin and insertion points were expressed using four different methods (4x4 grid box method, percentage position in the grid box for the medio-lateral projection, the percentage position orientated at different landmarks and the clock-face scale method). RESULTS: The relative positions of the centre of origin and insertion points of the MGHL were located constantly in radiographs in relation to anatomical landmarks in the canine shoulder. Therefore the described methods are useful for determination. CONCLUSION: The radiographic location of the origin and insertion points of the MGHL can be consistently predicted in radiographs of dogs with a body weight above 20 kg. CLINICAL SIGNIFICANCE: The reported data can be used to verify the correct placement of the insertion of bone anchors for stabilising a medial shoulder instability by ligament reconstruction in dogs.

Effects of hypothermia and re-warming on the inflammatory response in a murine multiple hit model of trauma.

INTRODUCTION: Although, hypothermia is a frequent event after trauma, it is unclear whether its beneficial or detrimental effects are more important. This study aims to quantify the effects of hypothermia and re-warming on the inflammatory response after fracture/hemorrhage and subsequent fracture stabilization with resuscitation. MATERIALS AND METHODS: Eighty-one male C57Bl/6 mice (aged 8-10 weeks, weighing 22.0+/-3.0 g) underwent femoral fracture and hemorrhage followed by resuscitation and splint fixation of the fracture. Animals were sacrificed 3h after induction of hemorrhage and fracture. Besides a sham group (n=6), four experimental groups were created: A: normothermia (n=12), B: hypothermia after trauma (n=21), C: re-warming after resuscitation and before stabilization (n=21), and D: hypothermia before trauma (n=21). Groups B-D were further subdivided into three subgroups according to the degree of hypothermia (subgroup 1: 35-33 degrees C, subgroup 2: 32.9-30.0 degrees C, and subgroup 3: 29.9-27.0 degrees C). Plasma cytokine (TNF-alpha, IL-6, and IL-10) and chemokine (MCP-1) concentrations were determined by ELISA, pulmonary permeability changes were quantified, and histological analysis of lung and liver tissues was performed. RESULTS: Normothermia resulted in a significantly increased early mortality rate. A significantly increased pro-inflammatory and decreased anti-inflammatory responses were also observed in normothermia as compared to hypothermia. The extent of these changes was most pronounced in the severe hypothermic group. Re-warming after mild hypothermia resulted in a pro-inflammatory response comparable to normothermia. CONCLUSION: Hypothermia has a beneficial effect on early survival after trauma, which appears to be independent of the level of hypothermia and re-warming. Re-warming, however, enhanced the pro-inflammatory response. Further studies with a longer posttraumatic observation period are required to investigate the long term effects of the hypothermia and re-warming-induced changes on the pro- and anti-inflammatory responses.

Secondary effects of femoral instrumentation on pulmonary physiology in a standardised sheep model: what is the effect of lung contusion and reaming?

Intramedullary nailing is the treatment of choice for patients with femoral shaft fractures. However, there is an ongoing debate in multiple trauma patients with associated lung contusion when primary or secondary definitive stabilisation of the long bone fracture should be performed, as nailing is thought to play an important role in the pathogenesis of adult respiratory distress syndrome (ARDS). In a standardised sheep model, this study aimed to quantify the development of acute pulmonary endothelial changes, to assess the activation of polymorphonuclear leucocytes (PMNL) and to observe the effects on the coagulation system associated with the reamed nailing procedure. Furthermore, the effect of coexisting lung contusion in an experimental model was evaluated. The animals were randomly assigned to one of four different groups (6 animals/group). In control groups, only a sham operation (thoracotomy) was performed, whereas in study groups, lung contusion was induced prior to femoral stabilisation either by external fixation or reamed femoral nailing. Using bronchoalveolar lavage (BAL) pulmonary permeability changes were quantified and PMNL activation was assessed by chemiluminescence. Additionally PMNL diapedesis and interstitial lung oedema were determined by histological analysis. All animals were sacrificed 4 h after the start of the femoral instrumentation. Without an associated lung injury, instrumentation of the femoral canal with the reamed nailing technique induced a transient increase in pulmonary permeability. In the face of an induced lung contusion, reamed femoral nailing resulted in significant increases in PMNL activation, pulmonary permeability and interstitial lung oedema, compared with external fixation. Without pulmonary contusion, reaming of the femoral canal was associated with a transient increase in pulmonary permeability. This was exacerbated in the presence of lung contusion along with increased PMNL activation. External fixation did not provoke similar changes. The findings of this study support the view that reaming of the femoral canal should be avoided in polytrauma patients with severe chest trauma as it could act as an additional stimulus for adverse outcome. Temporary external fixation appears to be a safe method for fracture stabilisation until inflammatory and coagulatory disturbances after trauma have been normalized.