Assessment of proficiency and competency in laboratory animal biomethodologies.

Personnel working with laboratory animals are required by laws and guidelines to be trained and qualified to perform biomethodologic procedures. The assessment of competency and proficiency is a vital component of a laboratory animal training program, because this process confirms that the trainees have met the learning objectives for a particular procedure. The approach toward qualification assessment differs between organizations because laws and guidelines do not outline how the assessment should be performed or which methods and tools should be used.

The effects of radiofrequency energy probe speed and application force on chondrocyte viability.

Objective: To determine the thermal effects of monopolar radiofrequency energy (mRFE) on bovine articular cartilage when it was moved at different speeds and using varying application forces.

Methods: Thirty-six fresh osteochondral sections divided into two groups (18 sections/group) were used in this study. The first group was tested at three speed rates of mRFE probe (1 mm/sec, 5 mm/sec and 10 mm/sec) at a constant force (50 g) applied to the probe tip.

Effects of thermal energy on chondrocyte viability.

Objective: To determine the critical temperature that reduces chondrocyte viability and evaluate the ability of chondrocytes to recover after exposure to the critical temperature.

Sample Population: Cartilage explants obtained from the humeral heads of 30 sheep.

Procedures: In a randomized block design, 318 full-thickness cartilage explants were collected from 30 humeral heads of sheep and cultured for up to 14 days.

Comparison of mechanical debridement and radiofrequency energy for chondroplasty in an in vivo equine model of partial thickness cartilage injury.

Objective: The purpose of this study was to develop a long-term model of cartilage injury that could be used to compare the effects of radiofrequency energy (RFE) and mechanical debridement as a treatment.

Methods: Partial thickness fibrillation of patellar cartilage was created in 16 mature ponies. Three months after the initial surgery all injured patellae were randomly selected to receive one of the four treatments (n = 8/treatment): (1) control, (2) mechanical debridement with a motorized shaver, (3) TAC-CII RFE probe, and (4) CoVac 50 RFE probe.

Effect of simulated shoulder thermal capsulorrhaphy using radiofrequency energy on glenohumeral fluid temperature.

Purpose: To determine joint fluid temperatures at different time intervals during treatment with radiofrequency energy (RFE) applied in intermittent and continuous treatment manners under flow or no-flow conditions using a simulated shoulder joint model.

Type Of Study: In vitro measurement of simulated joint fluid temperature during RFE treatment.

Methods: A custom-built jig with a chamber (volume size, 25 mL) was used to mimic the adult human shoulder.

In vivo transplantation of neonatal ovine neocartilage allografts: determining the effectiveness of tissue transglutaminase.

Following transplantation of ovine neocartilage allografts, 26 sheep were divided into groups according to the following weight-bearing schedule: 8-week nonweight bearing (8NWB, n=14), and 8-week nonweight bearing+4-week weight bearing (8NWB+4WB, n=12). In addition, 7 and 6 sheep, respectively, in the 8NWB and 8NWB+4WB groups received tTG treatment after allograft transplantation, whereas the remaining 13 sheep in these groups did not receive tTG. Finally, 8 sheep served as sham-operated controls without allograft transplantation.

Percutaneous injection of recombinant human bone morphogenetic protein-2 in a calcium phosphate paste accelerates healing of a canine tibial osteotomy.

Background: In this study, we evaluated the capacity of a single percutaneous injection of recombinant human bone morphogenetic protein-2 (rhBMP-2) delivered in a rapidly resorbable calcium phosphate paste (alpha-BSM) to accelerate bone-healing in a canine tibial osteotomy model. We hypothesized that the osteotomy sites would heal faster after percutaneous delivery of rhBMP-2/alpha-BSM than they would after injection of alpha-BSM alone or after no treatment.

Methods: Bilateral tibial osteotomy was performed and the sites were stabilized with external fixators in sixteen dogs.

A comparison of joint stability between anterior cruciate intact and deficient knees: a new canine model of anterior cruciate ligament disruption.

Transection of the canine anterior cruciate ligament (ACL) is a well-established osteoarthritis (OA) model. This study evaluated a new method of canine ACL disruption as well as canine knee joint laxity and joint capsule (JC) contribution to joint stability at two time points (16 and 26 weeks) after ACL disruption (n=5/time interval). Ten crossbreed hounds were evaluated with force plate gait analysis and radiographs at intervals up to 34 weeks after monopolar radiofrequency energy (MRFE) treatment of one randomly selected ACL.

Comparison of three methods of gluteal muscle attachment to an allograft/endoprosthetic composite in a canine model.

This study used radiography, gait analysis, gluteal muscle mass, mechanical testing, and qualitative histology to compare three methods of gluteal muscle attachment to an allograft/endoprosthetic composite of the proximal 25% of the femur in an in vivo canine model. The three methods of gluteal muscle attachment were identical to those used clinically in human patients for hip revision and proximal femoral limb salvage: the host gluteal tendon sutured to the allograft tendon (tendon group), the host greater trochanter with intact gluteal tendons secured to the allograft with a cable-grip system (grip group), and periosteally vascularized proximal femoral bone onlay with intact tendons wrapped around the allograft (wrap group). On the basis of radiographs taken every 2 months, the tendon group had more graft fractures than did the grip or wrap group.

Effect of intramedullary polymethylmethacrylate and autogenous cancellous bone on healing of frozen segmental allografts.

This study was designed to compare bone mineral density, periosteal callus production, new bone formation, bone porosity, histologic appearance, and union of mid-diaphyseal segmental allografts of the femur stabilized with an interlocking nail technique in a canine model 6 months after the procedure. An in vivo study was performed to compare the effects of augmenting interlocking nail fixation with an interlocking nail alone, intramedullary polymethylmethacrylate, intramedullary polymethylmethacrylate and autogenous cancellous bone applied to the periosteal surface of the host-allograft junction, autogenous cancellous bone applied to the endosteal surface of the allograft, autogenous cancellous bone applied to the periosteal surface of the host-allograft junction, and autogenous cancellous bone applied to the periosteal surface of the host-allograft junction and to the endosteal surface of the allograft. There were no differences among treatments for bone mineral density at any time interval.

Effect of nonablative laser energy on the joint capsule: an in vivo rabbit study using a holmium:YAG laser.

Background And Objective: The nonablative application of holmium:yttrium-aluminum-garnet (Ho:YAG) laser energy to the joint capsule of patients with glenohumeral instability has been found to shrink capsular tissue and to help stabilize the joint. The purpose of this study was to evaluate the effect of nonablative laser energy on the short-term histological properties of joint capsular tissue in an in vivo rabbit model.

Study Design/materials And Methods: Eighteen mature New Zealand white rabbits were used in this study.

The effect of thermal heating on the length and histologic properties of the glenohumeral joint capsule.

The purpose of this study was to evaluate the effect of temperature on shrinkage and the histologic properties of glenohumeral joint capsular tissue. Six fresh-frozen cadaveric shoulders were used for this study. Seven joint capsule specimens were taken from different regions from each glenohumeral joint and assigned to one of seven treatment groups (37 degrees, 55 degrees, 60 degrees, 65 degrees, 70 degrees, 75 degrees, 80 degrees C) using a randomized block design.

The effect of nonablative laser energy on joint capsular properties. An in vitro histologic and biochemical study using a rabbit model.

The purpose of this study was to evaluate the effect of laser energy at nonablative levels on joint capsular histologic and biochemical properties in an in vitro rabbit model. The medial and lateral portions of the femoropatellar joint capsule from both stifles of 12 mature New Zealand White rabbits were used. Specimens were divided into three treatment groups (5 watts, 10 watts, and 15 watt) and one control group using a randomized block design.

The effect of nonablative laser energy on the ultrastructure of joint capsular collagen.

This study was designed to evaluate the effect of laser energy at nonablative levels on the ultrastructure of joint capsular collagen. The femoropatellar joint capsules of six mature New Zealand white rabbits were harvested immediately after death. Specimens were divided into three treatment groups (5, 10, and 15 watts) and one control group.

Treatment of inflammatory arthritis by synovial ablation: a comparison of the holmium: YAG laser, electrocautery, and mechanical ablation in a rabbit model.

Background And Objective: Although the majority of patients with immune-mediated inflammatory arthritis are managed conservatively, some patients may require synovectomy if they have persistent pain secondary to chronic unresponsive swelling of a joint. In this study, three methods of synovial ablation using laser energy, electrocautery, and mechanical debridement were compared in an in vivo chronic synovitis rabbit model. STUDY DESIGN/MATERIALS, AND METHODS: In the first phase of this study, the optimal laser energy/pulse frequency combination for synovial ablation in this model was determined.

Atrophic nonunion can be predicted with dual energy x-ray absorptiometry in a canine ostectomy model.

This study demonstrated that dual energy x-ray absorptiometry can be used to distinguish between normal union and atrophic nonunion, with high sensitivity and high negative predictive value, by 8 weeks after surgery in a canine model. Eighteen adult mixed-breed dogs were divided into two equal groups: normal union and atrophic nonunion. In the normal union group, a 5 mm mid-diaphyseal transverse ostectomy was performed in the right tibia, and the bone was stabilized with a unilateral external fixator.

Comparison of allograft/endoprosthetic composites with a step-cut or transverse osteotomy configuration.

This study was designed to compare the biomechanical and functional characteristics of allograft/endoprosthetic composites of the proximal 25% of the femur repaired with either a transverse or a step-cut osteotomy, using a canine model (10 dogs, five with each type of osteotomy). Serial radiography and weight-bearing studies were performed monthly, and mechanical testing was done 6 months after surgery. The femora were tested in torsion and compared with the contralateral control (insertion of a femoral component but no osteotomy).

The effect of nonablative laser energy on joint capsular properties. An in vitro mechanical study using a rabbit model.

To evaluate the effect of laser energy at nonablative levels on the mechanical properties of joint capsular tissues, we tested the femoropatellar joint capsules of 12 mature New Zealand White rabbits. Specimens were divided into three treatment groups (5, 10, and 15 watts) and one control group. All specimens were first nondestructively mechanically tested to determine stiffness and viscoelastic properties and then treated with laser energy or served as a control.

Comparison of healing of allograft/endoprosthetic composites with three types of gluteus medius attachment.

This study compared three methods of gluteus medius tendon attachment to an allograft/endoprosthetic composite of the proximal 25% of the femur in a canine model. The three methods were bone to bone, tendon to bone, and tendon to tendon attachment. In an in vivo study, 24 dogs were assigned to three groups of eight dogs each, and serial radiography and weight-bearing analyses were performed throughout the study.

Dual-energy x-ray absorptiometry and force-plate analysis of gait in dogs with healed femora after leg-lengthening plate fixation.

Dual-energy x-ray absorptiometry was used to measure bone mineral density of four regions in healed femora of nine dogs after fracture fixation with a leg-lengthening plate. Six to 85 months (mean, 46 months) after surgery, the bone mineral density of healed femora was not significantly different from the contralateral uninjured femora (P > .05; power = 0.

Dual-energy X-ray absorptiometry of canine femurs with and without fracture fixation devices.

The effect of 5 fracture fixation methods on bone mineral density (BMD) measurement of femurs, using dual-energy X-ray absorptiometry (DXA) was determined in a canine model. Six regions of interest were measured, including the entire femur, the diaphysis of the femur, and small regions centered over the middiaphysis of the bone (lateral middiaphyseal cortex, medial middiaphyseal cortex, middiaphyseal medullary canal, and total middiaphysis). Eight unpaired femurs were collected and scanned by use of DXA before (5 separate scans/femur) and after (5 separate scans/femur) fixation by use of 1 of 5 fixation methods.

The effect of increasing gap width on localized densitometric changes within tibial ostectomies in a canine model.

Dual-energy X-ray absorptiometry (DXA) was used to quantitate the localized densitometric changes that occur early (0-16 weeks) in a tibial ostectomy model of three different gap widths in 15 dogs. Dogs were divided into three equal groups. A 5-mm (group 1), 15-mm (group 2), or 25-mm (group 3) unilateral tibial ostectomy was performed and stabilized with a unilateral external skeletal fixator in each dog.

Dual energy x-ray absorptiometry of implanted femora after cemented and press-fit total hip arthroplasty in a canine model.

The effect of a press-fit and cemented titanium alloy endoprosthesis on the measurement of bone mineral density (BMD) of the proximal femur in a canine model with dual energy x-ray absorptiometry (DXA) was determined. Seven regions of interest, corresponding to zones 1-7 according to Gruen et al., were measured.

Recovery of soluble dietary fiber is dependent on the method of analysis.

The effects of different methods on the distribution of total neutral sugars (TNS), uronic acids (UA), and beta-glucans (beta G) between the soluble (S) and insoluble (I) fractions of dietary fiber (DF) were determined for peas, kidney beans, oat bran, rice, and macaroni. Incorporation of a protease step into the Theander method "A" modestly increased, and addition of a pepsin digestion further increased the proportion of total fiber recovered in the S fraction. The effect of extraction method on the distribution of TNS, UA, and beta G between the S and I fractions varied with the food.