Outcomes and complications reported from a multiuser canine hip replacement registry over a 10-year period

Abstract

Objective: To report outcomes and complications associated with total hip replacements (THR) using a multiuser canine hip registry (CHR) and owner-administered questionnaire.

Study design: Prospective longitudinal clinical study.

Animals: Dogs (n = 1852).

Methods: Total hip replacement cases submitted to a CHR were reviewed. An online questionnaire including an adapted "Liverpool Osteoarthritis in Dogs" (LOAD) score was e-mailed to owners. Data were analyzed to determine associations between clinical variables and the agreement by veterinary surgeons and owners for complications.

Results: A group of 1329 (72%) dogs had unilateral THRs and another group of 523 (28%) dogs had bilateral THRs, resulting in 2375 THRs. Indications included hip dysplasia and osteoarthritis (n = 2028/2375, 85%). Implants were manufactured by Kyon (n = 1087, 46%), BioMedtrix CFX (n = 514, 22%), BioMedtrix hybrid (n = 264, 11%), BioMedtrix BFX (n = 221, 9%), and Helica (n = 107, 4.5%). Median veterinary surgeon and owner follow up were 1328 and 900 days respectively. Postoperative LOAD scores (21 ± 9) reported by 461 owners improved compared to preoperative scores (11 ± 9) (P < .001). Veterinary surgeons reported complications in 201/2375 (8.5%) THRs and owners in 107/461 (23%) THRs, with moderate agreement (weighted kappa = 0.44). No associations were identified between complications and weight, age, sex, or breed. BioMedtrix BFX and Helica implants were associated with increased complications (P = .031) when used for revisions of femoral head and neck excisions.

Conclusion: Excellent outcomes, including improved canine mobility, were reported after THRs. Complications were underreported by veterinary surgeons compared to owners in this first multiuser CHR.

Clinical significance: Canine THRs are safe, effective procedures but THR implants should be carefully selected when revising femoral head and neck excisions.

FIGURE 1

A flowchart representing the number of THR surgeries registered on the CHR database. THR, total hip replacement; CHR, canine hip registry

FIGURE 2

The most commonly presented dog breeds on the CHR database that have had THRs

FIGURE 3

The numbers of implants from different THR systems present on the CHR database. THR, total hip replacement, CFX, Cemented fixation, BFX, Biologic fixation.

FIGURE 4

The increase in the number of dogs over the years in relation to the implant type on the CHR database. CFX, Cemented fixation, BFX, Biologic fixation.

FIGURE 5

Indications for THR on the CHR database. THR, total hip replacement.

FIGURE 6

Percentage of complications reported by veterinary surgeon on the CHR database. Complications were categorized according to severity (major/minor/catastrophic). CHR, canine hip registry. VS, veterinary surgeon

FIGURE 7

Veterinary surgeon reported complications related to different THR implant systems. THR, total hip replacement. VS, veterinary surgeon, CFX, Cemented fixation, BFX, Biologic fixation.

FIGURE 8

Length of time owners of dogs registered on the CHR database replied to the online annual questionnaire following THR. CHR, canine hip registry; THR, total hip replacement

FIGURE 9

Minimum to maximum values of preoperative (n = 424) and postoperative (n = 458) LOAD scores. There is a significant difference between the preoperative and postoperative LOAD scores (P < .0001). Significance is set at P < .05. LOAD, Liverpool Osteoarthritis in Dogs

FIGURE 10

Minimum to maximum values of preoperative and postoperative LOAD scores within different time frames since the date of the initial THR. Significance is set at P < .05. Submission from owners include: pre 0‐12 (n = 47), post 0‐12 (n = 47), pre 12‐24 (n = 94), post 12‐24 (n = 93), pre 24‐36 (n = 92), post 24‐36 (n = 99), pre 36‐48 (n = 91), post 36‐48 (n = 92), pre 48‐60 (n = 54), post 48‐60 (n = 59), pre 60‐72 (n = 17), post 60‐72 (n = 26), pre 72‐82 (n = 7), post 72‐82 (n = 15), pre 82‐96 (n = 14), post 82‐96 (n = 16), pre 96‐108 (n = 10), post 96‐108 (n = 11), pre 108‐120 (n = 8), post 108‐120 (n = 10). LOAD, Liverpool Osteoarthritis in Dogs. Pre, preoperative LOAD score. Post, postoperative LOAD score. THR, total hip replacement

FIGURE 11

Percentage of complications reported by both veterinary surgeon and owners when the same number of dogs were compared. Complications were categorized according to severity (major and minor). O, owner. VS, veterinary surgeon.

FIGURE 12

Owner reported complications related to different THR implant systems. THR, total hip replacement, CFX and BFX