34th Annual Scientific Meeting proceedings

Objectives:

We report on type, location and incidence of soft tissue and bone pathology and describe their interrelations as observed on MRI. We hypothesized, MRI precisely and completely delineates menisco-cruciate, meniscotibial, meniscofemoral and collateral desmopathies and tibial-femoro-patellar lesions as lameness source. We also hypothezise that MRI confirms pathology co-existence, reveals lesions missed or underdiagnosed on traditional diagnostics and therefore, may influence treatment.

Methods:

MRI-scans after positive stifle-blocks without abnormalities or clear findings on other diagnostics, were reviewed. Breed, age, gender, duration and grade of lameness, MRI-anesthesia-time and findings were recorded. Several MRI-sequences were acquired in dorsal/sagittal/transverse planes. Arthroscopy was performed if pathology was accessible. Retrospectively, MRI-findings were compared to radiographic/ultrasonographic/arthroscopic examinations.

Results:

230 horses met inclusion criteria (WB=58,7%;QH=13%;Ponys=5,7%;others=22,6%;age=11,5yrs[Ø];lameness-duration=25,2wks[Ø];grade=3/5[Ø]). Significantly more soft-tissue than bone lesions were detected. Anesthesia-time averaged 62min. Meniscopathies occurred more frequently medial (48,3%) than lateral (37,4%),[tears>degenerations/fibrillations/displacements]). Cruciate desmopathy was significantly more observed cranially (75,6%) than caudally (27%). Menisco-tibial ligaments were more damaged (62,6%) than collateral/menisco-femoral/patellar (degenerations/fibrillations > tears). Frequently, soft-tissue lesions co-existed. Femoral/tibial/patellar remodeling/sclerosis/bone-marrow-lesions were observed in descending order. Meniscopathy co-existed in 50% of bone-cysts. Retrospectively, ultrasonographic/radiographic examinations commonly failed to identify/follow lesions. Although arthroscopy allowed probing/revision of superficial lesions, degree/extent of meniscal tears/degenerations, cruciate desmopathies/bone-marrow-lesions was unreliably/incompletely confirmed.

Conclusions:

Single and co-existent soft-tissue and bone-pathology contributed to lameness but conventional diagnostics missed or underdiagnosed pathology. Conversely, MRI portrayed lesions more reliably and thus, may influence therapy. Combining MRI and arthroscopy appeared useful for better understanding of stifle pathology, treatment and prognosis.