Radiographic, Surgeon and Owner Assessment of the BioMedtrix TATE®Elbow Arthroplasty

Recall Bias in Client-Reported Outcomes in Canine Orthopaedic Patients Using Clinical Metrology Instruments

OBJECTIVE

 The aim of this study was to determine the accuracy of client recollection of their dogs' preconsultation status using clinical metrology instruments such as the Liverpool Osteoarthritis in Dogs (LOAD) and Canine Brief Pain Inventory (CBPI) questionnaires in dogs presenting to a referral orthopaedic clinic.

STUDY DESIGN

 This is a longitudinal prospective cohort study of client-owned dogs presenting for investigations of lameness (n = 217). LOAD and CBPI questionnaires were completed by the owners at the first consultation (T0). Owners were contacted at 2 (T1), 6 (T2), and 12 (T3) months and asked to recall their dogs' T0 status by completing another LOAD and CBPI questionnaire. The agreement between the T0 and recalled LOAD and CBPI scores was determined using the two-way mixed effects intraclass correlation coefficient (ICC). The Wilcoxon signed-rank test was used to determine the difference between scores.

RESULTS

 For the LOAD scores, there was moderate agreement between T0 and T1 (ICC: 0.64) and T0 and T2 (ICC: 0.53) scores and poor agreement between T0 and T3 (ICC: 0.496). For the CBPI Pain Severity Scores, there was poor agreement between T0 and all three subsequent time points (ICC < 0.5). For the CBPI Pain Interference Scores, there was moderate agreement between T0 and T1 (ICC: 0.57) and T2 (ICC: 0.56) scores and poor agreement between T0 and T3 (ICC: 0.43).

CONCLUSION

 The LOAD and CBPI questionnaires are subject to recall bias. Studies reporting retrospectively acquired CMI data should be interpreted with caution.

Clinical effectiveness and safety of intraarticular administration of a 117m Tin radiocolloid (Synovetin OATM ) for treatment of early and intermediate grade osteoarthritis of the elbow in a dose finding study conducted in 44 dogs

Osteoarthritis of the elbow joint secondary to elbow dysplasia is common in dogs. Intraarticular radionuclide injection is thought to suppress both synovitis and inflammatory pain mediators in the joint which are not directly addressed by current treatments. This dose-finding investigation was a longitudinal, prospective, experimental parallel group, post-test study with repeated measures. Forty-four dogs, with low to intermediate-grade osteoarthritis, received a single injection into their most clinically affected elbow joint and were randomized into three treatment cohorts; 37 MBq, 64.75 MBq, or 92.5 MBq (normalized to the body surface area of a 22 kg dog) of 117m Sn radiocolloid. Dogs were assessed monthly by owners, using the canine Brief Pain Inventory (cBPI), and at 1, 3, 6, 9, and 12 months intervals by investigators. Positive responses to treatment were observed by both owners and clinicians in all dose groups with the medium dose group having the highest and most durable response rate based on cBPI scores. The results of this study support the use of 117m Sn radiocolloid as a primary treatment of osteoarthritis in low to intermediate-grade osteoarthritis of the canine elbow.

The use of subchondral bone topography to approximate the center of rotation of the elbow joint in dogs

OBJECTIVES

The aim of this study was to compare the approximate center of rotation in normal and diseased elbows in dogs.

STUDY DESIGN

Cross-sectional study SAMPLE POPULATION: Computer tomography scans of nine dogs with unilateral fragmented medial coronoid process (FMCP).

METHODS

A board certified radiologist confirmed that each dog had unilateral FMCP, and a normal contralateral elbow. Digital 3D models of all elbow joints were uploaded into a surgical planning software package. Four axes approximating the center of rotation (COR) of elbow joints were generated using five geometric shapes based on subchondral topography of the humeral condyle radius and ulna. Images showing the locations where axes exited the medial and lateral cortex of the humeral condyle were captured and imported into a second software package, for measurement of distances between exit points and the origin of a system of axes.

RESULTS

In normal joints 20/27 (74%) axes exited the medial cortex, and 25/27 (93%) axes exited the lateral cortex cranial and distal to the medial and lateral epicondyles, respectively. In diseased joints 22/27 (81%) axes exited medial cortex and 19/27 (70%) axes exited the lateral cortex, caudal and distal to the medial and lateral epicondyles, respectively.

CONCLUSION

Based on CT- derived geometry, the COR of elbow affected with FMCP was generally more caudal than normal.

CLINICAL SIGNIFICANCE

External landmarks approximating the location of the elbow COR are provided, and while not validated, may assist in planning, creation, and assessment of procedures for FMCP.

Serum acute-phase protein concentrations following uncomplicated total hip arthroplasty in dogs

OBJECTIVES

To establish preoperative and postoperative serum C reactive protein (CRP) and serum amyloid A (SAA) levels in dogs undergoing uncomplicated total hip arthroplasty (THA).

STUDY DESIGN

Prospective clinical trial.

ANIMALS

Eighteen client-owned dogs.

METHODS

Dogs undergoing THA were recruited. Serum CRP and SAA levels were measured in all dogs the day prior to surgery, and 3 and 6 months following surgery. All dogs received a physical examination and underwent radiography at each visit, and dogs with complications were excluded from the study. For continuous numeric data, histograms were generated and evaluated for normality. A 1-way repeated measures ANOVA was performed to find differences between time points.

RESULTS

No complications were encountered in any of the recruited dogs. Median age was 30 months (12-66), and the median bodyweight was 27.3 kg (22.3-40.2). Mean CRP concentrations in the preoperative, 3-month, and 6-month periods were 3.8 mg/L ± 4.4, 0.8 mg/L ± 1.9, and 1.4 mg/L ± 1.4, respectively. The mean SAA concentrations in the preoperative, 3-month, and 6-month periods were 13.9 mg/L ± 8.8, 14.1 mg/L ± 12.6, and 18.4 mg/L ± 15.1, respectively. There were no differences for each parameter between time points.

CONCLUSION

C-reactive protein and SAA levels were consistent with levels previously established for noninflammatory and normal conditions in dogs.

CLINICAL SIGNIFICANCE

Postoperative CRP and SAA concentrations were low by 3 months following uncomplicated THA.

Canine Elbow Dysplasia: Medial Compartment Disease and Osteoarthritis

Erosion of the articular cartilage of the medial compartment of the elbow (the humeroulnar articulation) secondary to incongruency associated with elbow dysplasia or traumatic injury has been termed, medial compartment disease. When nonsurgical strategies to manage osteoarthritis (OA) fail, surgical solutions may be warranted. Surgical strategies reduce pain through off-loading of the medial compartment by load-shifting osteotomies of the humerus or ulna. Other strategies involve replacement of portions or all of the articular surface of the medial compartment. With global elbow joint OA (medial and lateral compartment), a total elbow replacement may be required.

Evaluation of the milling technique on the component-bone interface in the TATE elbow

OBJECTIVE

To determine whether the surgeon can influence the accuracy of milling during the TATE elbow arthroplasty by applying force to the milling arm during the milling procedure.

STUDY DESIGN

In vitro study on Sawbone specimens.

SAMPLE POPULATION

Thirty identical solid foam models of the canine right humerus, elbow joint, and antebrachium (size large).

METHODS

TATE elbow arthroplasty was performed on 30 elbows equally divided into 3 types of forces applied to the milling arm: (1) no force, (2) a maximally converging force, and (3) a maximally diverging force using the center of rotation post as a reference point. The resulting component-bone interface and post fit were quantified with digital photography.

RESULTS

The component-bone interface gap differed between techniques for most angles. The application of convergent or divergent milling forces frequently increased the component-bone interface gap. Post fit was also influenced by the milling technique, application of a convergent or divergent milling force affecting the fit of multiple posts. Interface gaps tended to be greater on the lateral aspect, an area that is not visible to the surgeon intraoperatively.

CONCLUSION

In this bone model study, application of convergent or divergent forces during milling frequently resulted in greater component-bone interface gaps and poorer post fit than when a neutral position was maintained.

CLINICAL SIGNIFICANCE

Surgeons may affect implant fit within the constraints of the current arthroplasty system if they do not maintain a neutral position during milling. Greater component-bone interface gaps and poorer post fit may affect component osseointegration and lead to aseptic implant loosening.