Sequential measurements of the tibial plateau angle in large-breed, growing dogs

Center of rotation of angulation-based leveling osteotomy for stifle stabilization in skeletally immature dogs

OBJECTIVE

To describe short-term outcomes of center of rotation of angulation (CORA)-based leveling osteotomy (CBLO) in skeletally immature dogs with cranial cruciate ligament (CrCL) injury.

STUDY DESIGN

Retrospective case series.

ANIMALS

Fifteen skeletally immature dogs (16 stifles).

METHODS

Medical records of dogs with CrCL injury and radiographically documented open proximal tibial physis and tibial tuberosity apophysis managed with CBLO were reviewed. Clinical assessment, radiographic assessment, and complications were reviewed.

RESULTS

Fifteen dogs (16 stifles) with radiographically documented open proximal tibial physis and tibial tuberosity apophysis and CrCL injury underwent a CBLO. Mean tibial plateau angle (TPA) was 26° preoperatively, 9° postoperatively, and 9° at final recheck. One dog developed 10° recurvatum of the proximal tibia secondary to inadvertent over rotation of the tibial plateau (TPA 3°) to protect primary repair of an insertional CrCL avulsion. Correction of the recurvatum was declined as the dog had full limb function. Two dogs developed a valgus deformity secondary to a plate screw engaging the distolateral aspect of the proximal tibial physis. Owners of these dogs reported normal function but requested surgical revision to prevent long-term problems secondary to abnormal weight bearing. Both dogs regained full function following recovery from revision surgery. At a mean time of 23 months following surgery, all dogs continued to have full function as per phone conversation with owners.

CONCLUSION

With proper preoperative planning, CBLO is an option for skeletally immature dogs with CrCL injury.

Double-cut center of rotation of angulation-based leveling osteotomy for treatment of cranial cruciate ligament deficiency and excessive tibial plateau angle secondary to growth anomaly in two dogs

CASE DESCRIPTION

A 4-year-old female Staffordshire Bull Terrier (dog 1) and a 6-year-old male Yorkshire Terrier (dog 2) were evaluated because of left pelvic limb lameness.

CLINICAL FINDINGS

Both dogs had a partial rupture of the left cranial cruciate ligament associated with a unilateral excessive tibial plateau angle (51° in dog 1 and 41° in dog 2) secondary to a growth anomaly.

TREATMENT AND OUTCOME

Both dogs underwent a double-cut center of rotation of angulation-based leveling osteotomy combining rotation of the proximal fragment with a cranial closing wedge ostectomy. The procedure allowed leveling of the tibial plateau to a final angle of 11° in one dog and 10° in the other without perioperative complications. Both dogs had excellent functional outcomes ≤ 4 months after the surgery. No postoperative complications were reported during follow-up (12 months and 9 months for dogs 1 and 2, respectively).

CLINICAL RELEVANCE

Results for these dogs suggested that double-cut center of rotation of angulation-based leveling osteotomy can be considered as a viable treatment option for cranial cruciate ligament deficiency associated with excessive tibial plateau angle.

Lateral and medial tibial plateau angles in normal dogs. An osteological study

OBJECTIVES

To measure lateral and medial tibial plateau angle values in isolated canine tibiae and to compare lateral and medial tibial plateau angle values between dogs based on sex and breed.

METHODS

Tibiae of 90 dogs from 24 different breeds were used. Photographs were taken of the medial and lateral aspects of the tibiae for measurement of the medial and lateral tibial plateau angles. Additionally, the medial tibial plateau angle was measured from radiographs of the tibiae. Two-way analysis of variance was used to test the effects of side, sex and breed on the medial and lateral tibial plateau angles as measured from photographs as well as the medial tibial plateal angles as measured from radiographs. The photographic and radiographic medial tibial plateau angles were compared by paired t-test, whereas the medial and lateral photographic tibial plateau angles were compared by t-test.

RESULTS

When all dogs were included in the analysis, the difference between the mean medial tibial plateau angle (24.0 ± 3.19°) and the mean lateral tibial plateau angle (25.5 ± 3.84°) as measured from photographs was significant (p <0.05). The difference in the photographic medial tibial plateau angle between male and female dogs was significant (p <0.05), whereas the difference in the photographic lateral tibial plateau angle between sexes was not significant. There was a significant difference between the medial and lateral tibial plateau angles as measured from photographs in male dogs (p <0.05) but not in female dogs. Breed comparisons also showed significant differences for the photographic lateral tibial plateau angle (p <0.05).

CLINICAL SIGNIFICANCE

The axial rotation of the femoral condyles on the tibial plateau is probably affected by the discrepancy between the medial and lateral tibial plateau angles, and this difference in certain breeds might influence the prevalence of cranial cruciate ligament disease.

Effect of anatomic variation in caudal tibial plateau on the tibial plateau angle in dogs: a cadaveric study

OBJECTIVES

To determine the effect of using two different landmarks to identify the caudal point on the joint orientation line in the sagittal plane in tibial plateau angle measurement in dogs: the caudal margin of the medial condyle as the anatomic tibial plateau angle and the tibial insertion of the caudal cruciate ligament as the conventional tibial plateau angle.

METHODS

A total of 170 tibiae from 85 mid- and large-breed dogs were used. The two joint orientation lines were drawn on photographic images of the bones. The angles between the line perpendicular to the tibial axis and the two lines were then measured as the anatomic and conventional tibial plateau angle.

RESULTS

The mean conventional tibial plateau angle (25·2 ±2·60°) and anatomic tibial plateau angle (23·5 ±2·59°) differed significantly (P<0·001), and the degree of this difference varied significantly among seven breeds (P<0·01).

CLINICAL SIGNIFICANCE

The results of this study suggest that the locations of the caudal margin of the medial condyle and the tibial insertion of the caudal cruciate ligament differed, leading to inconsistent identification of the joint orientation line depending on the landmark used.

Morphometric characteristics of the pelvic limbs of Labrador Retrievers with and without cranial cruciate ligament deficiency

OBJECTIVE-To evaluate skeletal characteristics of pelvic limbs with and without cranial cruciate ligament (CCL) deficiency in Labrador Retrievers. ANIMALS-30 adult purebred Labrador Retrievers. PROCEDURES-Pelvic limbs (n = 28) of 14 dogs without CCL deficiency were classified as control limbs, whereas the limbs of 16 dogs with CCL deficiency were considered affected by (18 limbs) or predisposed to (10 contralateral limbs of dogs with 1 affected limb) CCL deficiency. Skeletal characteristics were evaluated via physical examination, radiography, and computed tomography. Radiographic and computed tomographic variables were compared among limb groups by use of a mixed-model ANOVA. RESULTS-The tibial plateau slope was steeper in CCL-deficient limbs but not in predisposed limbs, compared with the slope in control limbs. The angle between diaphyseal and proximal tibial axes was increased in both CCL-deficient and predisposed limbs. The relative width of the proximal portion of the tibia and the inclination of the patellar ligament did not differ among limb groups. The overall and distal femoral anteversion angles were greater in CCL-deficient and predisposed limbs, whereas the femoral condyle trochanteric angle was decreased in those limb groups, compared with findings in control limbs. CONCLUSIONS AND CLINICAL RELEVANCE-Cranial angulation of the proximal portion of the tibia, excessive steepness of the tibial plateau, and distal femoral torsion appeared more likely to be associated with CCL deficiency than femoral angulation, tibial torsion, intercondylar notch stenosis, and increased inclination of the patellar ligament.

Radiographic measurement of canine tibial angles in the sagittal plane

OBJECTIVE

To describe a method for radiographic measurement of the mechanical joint angles of the tibia in the sagittal plane and report reference ranges for a population of dogs with cranial cruciate ligament disease, and specifically for Labrador Retrievers.

STUDY DESIGN

Retrospective evaluation of radiographs.

ANIMALS

Canine tibia (n=150) of dogs evaluated for cranial cruciate ligament disease; 104 tibiae were from Labrador Retrievers, 46 tibiae were from other medium- to large-breed dogs.

METHODS

Medial-lateral radiographs were used to establish anatomic landmarks and measure the mechanical cranial distal tibial angle (mCrDTA) and mechanical caudal proximal tibial angle (mCaPTA).

RESULTS

For all tibiae mean mCrDTA was 81.6 degrees and mCaPTA, 63.6 degrees . For Labrador Retriever tibiae mean mCrDTA was 81.7 degrees and mCaPTA, 63.8 degrees . For non-Labradors, means mCrDTA was 81.5 degrees and mCaPTA, 63 degrees . Labrador Retrievers were significantly younger than non-Labradors in our study population. No significant differences were noted between Labrador Retrievers and non-Labradors for mCrDTA or mCaPTA and correlations between mCrDTA and mCaPTA were neither strong nor significant.

CONCLUSION

A method was established for radiographic measurement of mechanical joint angles of the canine tibia in the sagittal plane. Reference ranges are reported for a population of Labrador Retrievers and a population of non-Labradors with cranial cruciate ligament disease.

CLINICAL RELEVANCE

Measurement method and reference ranges provided for mechanical tibial angles may be used to aid in diagnosis, surgical planning, and postoperative critique for hindlimb angular deformities.

Radiographic measurement of the proximal and distal mechanical joint angles in the canine tibia

OBJECTIVE

To describe a method for radiographic measurement of proximal and distal mechanical joint angles of the canine tibia. Normal ranges were established for a population of dogs, and specifically, Labrador retrievers, with cranial cruciate ligament rupture.

STUDY DESIGN

Retrospective study.

SAMPLE POPULATION

Tibiae (n=105) of dogs evaluated for cranial cruciate ligament rupture; 70 tibiae were from Labrador retrievers, 35 tibiae were from other breeds.

METHODS

Anatomic landmarks were established and craniocaudal radiographs were used to measure the mechanical medial proximal (mMPTA) and distal (mMDTA) tibial angles in the frontal plane.

RESULTS

Means (+/-SD) for all tibiae were mMPTA, 93.30+/-1.78 degrees, and mMDTA, 95.99+/-2.70 degrees. For Labrador retrievers, means were mMPTA, 93.38+/-1.81 degrees, and mMDTA 96.34+/-2.51 degrees. No significant differences were detected between Labrador Retrievers and non-Labrador retrievers with respect to mMPTA (power=0.5) or mMDTA (power=0.342). Labrador Retrievers were significantly younger than non-Labradors (P=.003).

CONCLUSION

A method for measurement of the mechanical joint angles of the canine tibia in the frontal plane was established and reference ranges for a population of dogs and Labrador Retrievers with cranial cruciate ligament rupture are reported.

CLINICAL RELEVANCE

The established method of measurement and references ranges can be used to aid in diagnosis, determining indications, and surgical planning for angular limb deformities of the tibia, especially when affected bilaterally. The methodology and reference values may also be used for postoperative critique.

Tibial Plateau Symmetry and the Effect of Osteophytosis on Tibial Plateau Angle Measurements

A novel technique was developed to estimate the caudal medial tibial plateau landmark in the face of osteophytosis to improve accuracy in tibial plateau angle measurements. Using this technique, tibial plateau angles were evaluated in 31 normal dogs before and 8 months after right cranial cruciate ligament transection. There was no significant difference in mean tibial plateau angle before or after induction of osteophytosis. Additionally, it was determined that 90% of dogs had a difference of =2° between right and left tibial plateau angles, which was considered symmetrical.