Lateral meniscal tears and stifle osteochondrosis in three dogs

Novel crescentic, medial-closing, medially translating, centre-of-rotation-of-angulation-based, levelling osteotomy for lateral compartment stifle disease with partial cranial cruciate ligament tear in two dogs

CASE HISTORY

Two mature, large breed dogs presented with chronic lameness and discomfort localised to the stifle.

CLINICAL FINDINGS

No hindlimb deformities were present on physical examination or radiographic evaluation. No stifle instability was present. Arthroscopy revealed severe (grade 5/5 modified Outerbridge score) cartilage erosion in the lateral compartment (femorotibial), marked degeneration of the lateral meniscus and early cranial cruciate ligament disease in both patients.

TREATMENT AND OUTCOME

Medial-closing, medially translating, centre-of-rotation-of-angulation-based, levelling osteotomy (mcmtCBLO) was performed in both patients. The procedure aims to shift the pelvic limb's mechanical axis medially to reduce pressure in the lateral compartment while also reducing craniocaudal shear forces by lowering the tibial plateau angle.Eight weeks after surgery one patient's lameness had resolved while the other had improved significantly. Second-look arthroscopy performed at this time revealed fibrocartilage formation in the lateral compartment without progression of cruciate disease in both cases. At long-term follow-up (approximately 3 and 5 years), favourable outcomes (no or minimal lameness, mild or moderate osteoarthritis) were identified on the long-term owner survey, lameness examination and radiographs.

CLINICAL RELEVANCE

mcmtCBLO reduced or eliminated short- and long-term lameness in these two cases afflicted by concurrent lateral compartment and early cranial cruciate ligament disease.

Ex vivo cadaveric study of a laterally placed Leipzig stifle distractor for arthroscopic evaluation of the lateral meniscus in dogs

OBJECTIVE

To evaluate safety and accuracy of lateral pin placement for the use of a Leipzig stifle distractor (LSD) and to assess improvements in visualization and treatment of the lateral meniscus in the canine stifle.

STUDY DESIGN

Ex vivo cadaveric study.

SAMPLE POPULATION

Paired canine cadaveric hind limbs (n = 10).

METHODS

Pins for the LSD were placed from lateral to medial in the distal femur and proximal tibia. Safety and accuracy of lateral pin placement were evaluated via anatomical dissection, computed tomography (CT), and arthroscopy. In every case, distraction of the lateral compartment of the femorotibial joint space was evaluated arthroscopically, and the meniscus was probed. Afterward, the limbs were assigned to 1 of 2 groups, and a partial meniscectomy was attempted with or without distraction. Stifles were disarticulated to evaluate the meniscectomy and iatrogenic cartilage damage.

RESULTS

Computed tomography revealed some variation in pin placement, although sufficient distraction was achieved for all stifle joints. No damage to the surrounding structures was observed during anatomical dissection, CT, or arthroscopy. Disarticulation provided evidence that using an LSD allowed for complete caudal horn meniscectomies and less articular cartilage damage than when meniscectomy was attempted with manual distraction.

CONCLUSION

Lateral placement of an LSD proved to be safe and effective for the distraction of the lateral femorotibial joint space and the examination and treatment of the lateral meniscus in dogs weighing 18-42 kg.

CLINICAL SIGNIFICANCE

Canine lateral meniscus pathology, although rare, leads to severe pain. A laterally placed LSD improves arthroscopic evaluation and treatment of this pathology.

Articular cartilage lesions associated with complete lateral meniscal tears in the dog

OBJECTIVE

To describe articular cartilage (AC) lesions associated with complete lateral meniscal tears in dogs.

STUDY DESIGN

Observational series.

ANIMALS

Seventeen dogs with arthroscopic evidence of a complete lateral meniscal tear and associated AC lesions.

METHODS

Medical records of dogs with arthroscopic evidence of complete lateral meniscal tear and associated AC lesions between March 2006 and December 2017 were examined for arthroscopic findings.

RESULTS

The cranial cruciate ligament (CrCL) was intact in 11 of 17 dogs, partially ruptured but competent in 4 of 17 dogs, and completely ruptured in 2 of 17 dogs. All dogs had grossly normal caudal cruciate ligament, medial meniscus, and AC of the medial compartment. In each dog, a complete radial tear of the caudal body of the lateral meniscus was associated with degenerative osteoarthritis (OA) of the lateral compartment of the stifle. The Outerbridge score of the lateral tibial condyle and lateral femoral condyle was 5 of 5 in 15 dogs, 3 of 5 in 1 dog, and 4 of 5 in 1 dog.

CONCLUSION

Dogs with complete tears of the lateral meniscus developed degenerative OA of the lateral compartment of the stifle leading to AC loss and clinical dysfunction.

CLINICAL SIGNIFICANCE

Complete lateral meniscal tears may occur as isolated injuries in dogs with a functional CrCL.

Systematic review of the prevalence, risk factors, diagnosis and management of meniscal injury in dogs: Part 1. [corrected]

OBJECTIVE

To systematically evaluate the evidence reporting the frequency and risk factors of meniscal injury in dogs with cranial cruciate ligament failure.

STUDY DESIGN

Systematic literature review.

MATERIALS AND METHODS

Research questions were defined. An electronic database search of PubMed and CAB Abstracts was performed during November 2013. Data were extracted for study participants, design, intervention, outcome measures and results. Studies were evaluated using a validated instrument for assessing methodological quality and assigned a quality index score. A level of evidence was then assigned to each study.

RESULTS

Sixty-two studies were identified. The median quality index score was 14 out of a possible 26. Twenty-four studies were prospective case series, 37 retrospective case series and 1 animal research study. There were no class I or class II studies, 24 class III studies and 38 class IV studies.

CLINICAL SIGNIFICANCE

Despite a large number of publications the quality of evidence was generally low. No one study or combination of studies provided high quality evidence to establish the true frequency or risk factors for meniscal injury in dogs with cranial cruciate ligament failure.