COMPUTED TOMOGRAPHIC ARTHROGRAPHY OF THE STIFLE FOR DETECTION OF CRANIAL AND CAUDAL CRUCIATE LIGAMENT AND MENISCAL TEARS IN DOGS

Medial joint line tenderness is an indicator for meniscal injuries in dogs

BACKGROUND

Medial meniscal injury is an important aspect of cranial cruciate ligament disease in dogs. This study examines whether caudomedial joint line palpation of the stifle is correlated with medial meniscal injury in canine stifles with concurrent cranial cruciate ligament disease.

METHODS

A total of 91 dogs (97 stifles) presenting with cranial cruciate ligament disease were assessed by palpation of the caudomedial joint line of the affected stifle by a single surgeon. Surgery was then performed to assess for injury to the medial meniscus. The odds of dogs with pain on palpation having a medial meniscal tear were then calculated, with the significance level set at p-value of 0.05.

RESULTS

Dogs showing pain on caudomedial joint palpation had 34.5 times (95% confidence interval 9.7‒125) greater odds of having a medial meniscal tear. Pain on caudomedial joint line palpation had a sensitivity of 0.86, specificity of 0.85, positive predictive value of 0.94, negative predictive value of 0.70 and accuracy of 0.86 for identifying dogs with a medial meniscal tear.

LIMITATIONS

The amount of pressure placed on the caudomedial joint line was not assessed and a control group was not included.

CONCLUSION

Medial joint line tenderness has a significant relationship with medial meniscal tear in dogs with cranial cruciate ligament disease.

Optimal Computed Tomographic Arthrography Protocol for Stifle Ligamentous Structure and Menisci in Dogs

This study aims to establish an optimized CTA protocol for qualitatively evaluating the ligamentous structures and menisci of the canine stifle. CTA of the stifle joint was conducted on six healthy beagle dogs. Each dog underwent a total of nine scans to evaluate various contrast protocols. These protocols involved three different concentrations of iodine (50, 100, and 150 mgI/mL) and three different volumes of contrast media injection (0.2, 0.3, and 0.4 mL/kg). Subsequently, the acquired arthrographic images were qualitatively assessed to determine the visibility of the stifle ligaments. The quantitative evaluation of CTA revealed that the cranial and caudal cruciate ligaments were more clearly visible in groups M2 (100 mgI/mL, 0.3 mL/kg) and M3 (100 mgI/mL, 0.4 mL/kg) in comparison to S1 (50 mgI/mL, 0.2 mL/kg) and L3 (150 mgI/mL, 0.4 mL/kg). The visibility of the medial meniscus was notably lower in S1 and S2 (50 mgI/mL, 0.3 mL/kg), while the lateral meniscus exhibited reduced visibility in S1. Overall, the high contrast settings (M2, M3) generally improved the visualization of the meniscofemoral ligament, meniscotibial ligament, and the intermeniscal ligament. For optimal evaluation of the canine stifle ligament using CTA, it is recommended to use 100 mgI/mL iodine at a dosage of 0.3 mL/kg or 0.4 mL/kg.

Determining predictive metabolomic biomarkers of meniscal injury in dogs with cranial cruciate ligament rupture

OBJECTIVES

This study used hydrogen nuclear magnetic resonance spectroscopy for the first time to examine differences in the metabolomic profile of stifle joint synovial fluid from dogs with cranial cruciate ligament rupture with and without meniscal injuries, in order to identify biomarkers of meniscal injury. Identifying a biomarker of meniscal injury could then ultimately be used to design a minimally invasive diagnostic test for meniscal injuries in dogs.

MATERIALS AND METHODS

Stifle joint synovial fluid was collected from dogs undergoing stifle joint surgery or arthrocentesis for lameness investigations. We used multi-variate statistical analysis using principal component analysis and univariate statistical analysis using one-way analysis of variance and analysis of co-variance to identify differences in the metabolomic profile between dogs with cranial cruciate ligament rupture and meniscal injury, cranial cruciate ligament rupture without meniscal injury, and neither cranial cruciate ligament rupture nor meniscal injury, taking into consideration clinical variables.

RESULTS

A total of 154 samples of canine synovial fluid were included in the study. Sixty-four metabolites were annotated to the hydrogen nuclear magnetic resonance spectroscopy spectra. Six spectral regions were found to be significantly altered (false discovery rate adjusted P-value <0.05) between groups with cranial cruciate ligament rupture with and without meniscal injury, including three attributed to nuclear magnetic resonance mobile lipids [mobile lipid -CH3 (P=0.016), mobile lipid -n(CH3 )3 (P=0.017), mobile unsaturated lipid (P=0.031)].

CLINICAL SIGNIFICANCE

We identified an increase in nuclear magnetic resonance mobile lipids in the synovial fluid of dogs with meniscal injury which are of interest as potential biomarkers of meniscal injury.

Associations between meniscal tears and various degrees of osteoarthritis among dogs undergoing TPLO for cranial cruciate ligament rupture

OBJECTIVE

The aim of this study was to evaluate the association between meniscal lesions and severity of osteoarthritis (OA) among dogs that underwent Tibial Plateau Leveling Osteotomy (TPLO) for stabilization of cranial cruciate ligament rupture (CrCLR) at the University of Tennessee in 2011-2017.

RESULTS

There were a total of 252 meniscal tears. Factors associated with diagnosis of medial meniscal tears (MMT) in dogs were severe OA in comparison to no OA (3.8 OR, 2.0-8.0 95% CI, 0.001 p-value), sporting and mixed breed group compared to other breed (3.6 OR, 1.7-7.6 95% CI, 0.004 p-value; 3.2 OR, 1.6-6.6 95% CI, 0.019 p-value, respectively), increasing age (1.1 OR, 1.0-1.2 95% CI, 0.018 p-value), complete CrCLR compared to partial (3.3 OR, 2.1-5.0 95% CI, < 0.001 p-value), and arthrotomy compared to arthroscopy (2.2 OR, 1.4-3.1 95% CI, 0.002 p-value). The factors that did not have significance in predicting MMT were weight, sex, lameness period, and side affected.

Orthopedic Imaging: A Practical Clinical Guide

Many imaging options are available to the practitioner both in-house and on a referral basis to help make a definitive diagnosis for orthopedic injuries. To guide treatment, a complete understanding of the nature and extent of the injury is ideal. While a thorough orthopedic physical examination is the first step, a complete diagnostic work-up will include at least one and often more than one imaging modality. The goal of this article is to discuss the imaging options for some of the more common orthopedic issues encountered in dogs to help guide the practitioner through the selection of which should be considered to accomplish a diagnosis.

Ex vivo comparison of 3 Tesla magnetic resonance imaging and multidetector computed tomography arthrography to identify artificial soft tissue lesions in equine stifles

OBJECTIVE

To determine the diagnostic performance of computed tomographic arthrography (CTA) and 3 Tesla magnetic resonance imaging (MRI) for detecting artificial meniscal, meniscotibial ligament (MTL) lesions and cruciate ligament (CL) lesions in horses.

STUDY DESIGN

Ex vivo controlled laboratory study.

ANIMALS

Nineteen stifles from adult horses.

METHODS

Stablike defects (n = 84) (16 mm long, 10 mm deep) were created in the menisci (n = 35), CLs (n = 24), and MTLs (n = 25) via arthroscopy prior to MRI and CTA (80 mL contrast at 85 mg/mL per joint). Two radiologists, unaware of the lesions, reached a consensus regarding the presence of lesions, based on 2 reviews of each study. Sensitivity and specificity of MRI and CTA were determined using arthroscopy as a reference and compared with McNemar's tests.

RESULTS

The sensitivity and specificity of MRI (41% and 86% respectively) and CTA (32% and 90% respectively) did not differ (P = .65). The sensitivity (MRI: 24%‐50%; CTA:19%‐40%) and specificity (MRI: 75%‐92%; CTA 75%‐100%) of imaging modalities did not differ when detecting lesions of the menisci, MTLs, and CLs (P = .1‐1.0). The highest sensitivities were achieved when MTLs were evaluated with MRI (50%) and CLs with both modalities (40%).

CONCLUSIONS

The diagnostic performance of CTA was comparable with that of MRI, with a low to moderate sensitivity and high specificity.

CLINICAL SIGNIFICANCE

Computed tomographic arthrography should be considered as an adjunct to diagnose CL injuries. This is important for equine clinicians, as the CL cannot be visualized adequately using basic imaging techniques preoperatively.

Moving Beyond the Limits of Detection: The Past, the Present, and the Future of Diagnostic Imaging in Canine Osteoarthritis

Osteoarthritis (OA) is the most common orthopedic condition in dogs, characterized as the chronic, painful end-point of a synovial joint with limited therapeutic options other than palliative pain control or surgical salvage. Since the 1970s, radiography has been the standard-of-care for the imaging diagnosis of OA, despite its known limitations. As newer technologies have been developed, the limits of detection have lowered, allowing for the identification of earlier stages of OA. Identification of OA at a stage where it is potentially reversible still remains elusive, however, yet there is hope that newer technologies may be able to close this gap. In this article, we review the changes in the imaging of canine OA over the past 50 years and give a speculative view on future innovations which may provide for earlier identification, with the ultimate goal of repositioning the limit of detection to cross the threshold of this potentially reversible disease.

Association of meniscal injury to joint space width on standard tibial plateau leveling osteotomy lateral radiographic projections of the canine stifle

Up to 70% of dogs with cranial cruciate ligament tears have concurrent meniscal injury, and these injuries can increase the risk of developing osteoarthritis and persistent lameness. Studies assessing joint space width on knee radiographs in people have indicated associations between joint space width and meniscal injuries. The aim of this prospective analytical study was to determine if there was an association between stifle joint space width on three different radiographic projections (the standard tibial plateau leveling osteotomy projections and a standing lateral projection) and meniscal injuries identified at surgery in dogs. There was a significant association between dogs with a meniscal tear and the corresponding joint space width on standard tibial plateau leveling osteotomy lateral radiographic projections (P-value = .0028). Based on receiver operator characteristic curve analysis, joint space widths measuring less than 3.43 mm may indicate a meniscal tear, with a corresponding 89.5% specificity and 40.5% sensitivity in dogs weighing 31 kg. Joint space narrowing is seen with meniscal tears in dogs, and radiography may be a noninvasive way to identify meniscal tears prior to surgery.

High-frequency ultrasound, computed tomography and computed tomography arthrography of the cranial cruciate ligament, menisci and cranial meniscotibial ligaments in 10 radiographically normal canine cadaver stifles

BACKGROUND

Bilateral non-traumatic cranial cruciate disease is frequently seen in originally unilateral cruciate pathology. Untreated cranial cruciate ligament disease and concurrent meniscal lesions cause progressive osteoarthritis and pain of the stifle joint. Early presurgical diagnosis is important, but remains difficult. The purpose of this ex vivo study was (1) to describe the ultrasonographic appearance of the canine cranial cruciate ligament (CrCrL), menisci and meniscal ligaments using a high-frequency linear transducer, (2) to determine the length of the CrCrL seen on ultrasonography (US) and (3) to describe and compare the appearance of the CrCrL, menisci and meniscal ligaments on US, computed tomography (CT) and computed tomography arthrography (CTA).

RESULTS

US and CT examinations were performed on 10 radiographically normal cadaveric stifles of adult dogs weighing more than 15 kg, followed by macroscopic and histologic evaluations. The CrCrL had a parallel hyperechoic fibrillar pattern at the insertion on the tibia and a hypoechoic structure more proximally in all stifles. This pattern was visible over 35% (median) of the total length of the ligament, with 50% (median) of the total length CrCrL that could be outlined. All medial menisci and 8 out of 10 of the lateral menisci showed hypoechoic lines within their bodies oriented obliquely to the direction of the ultrasound beam. Fifteen of the 20 cranial meniscotibial ligaments were detected, showing a hyperechoic fibrillar pattern. Normal macro- and microscopic appearance was observed in all menisci, with the radial bundles of collagen fibers at the level of and with similar orientation as the intrameniscal hypoechoic lines on US. The CrCrL, menisci and meniscal ligaments were of intermediate density on CT, but marked improvement of the border detection was obtained using CTA. Contrast within the CrCrL was observed in 4/10 stifles using CT and confirmed in 3/4 stifles on histology. One of these ligaments had a partial tear (5-10%) on macroscopic evaluation. None of the menisci showed any abnormalities on CTA.

CONCLUSIONS

Normal canine menisci are heterogeneous on high-frequency US and a fibrillar pattern may be observed in the cranial meniscotibial ligaments and the distal portion of the CrCrL. Linear areas of contrast may be detected within the cranial cruciate ligament of radiographically normal stifles.

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.

Erosion of the medial compartment of the canine elbow: occurrence, diagnosis and currently available treatment options

Erosion of the medial compartment of the elbow joint refers to full thickness cartilage loss with exposure of the subchondral bone (modified Outerbridge grades 4–5) of the medial part of the humeral condyle (MHC) and the corresponding ulnar contact area. This finding may appear in the absence of an osteochondral fragment or a cartilage flap, or in combination with fragmentation of the medial coronoid process (MCP) or osteochondritis dissecans (OCD) of the MHC. With regard to the prognosis, it is important to diagnose these severe erosions. Imaging of cartilage lesions by means of radiography, ultrasonography, computed tomography or magnetic resonance imaging is challenging in dogs. In contrast, direct arthroscopic inspection provides detailed information about the cartilage.

The treatment of these severe erosions is difficult because of the limited regenerative capacity of cartilage and presumed mechanical or physical triggering factors. Several conservative and surgical treatment methods have been proposed to treat elbows with severe cartilage defects. However, due to irreversible loss of cartilage, the prognosis in these cases remains guarded.

Accuracy of 3 Tesla magnetic resonance imaging using detection of fiber loss and a visual analog scale for diagnosing partial and complete cranial cruciate ligament ruptures in dogs

Canine cranial cruciate ligament rupture is often bilateral and asymmetrical, ranging from partial to complete rupture. The purpose of our diagnostic accuracy study was to assess the accuracy of 3 Tesla magnetic resonance imaging (MRI) detection of fiber loss and use of a visual analog scale in the diagnosis of complete versus partial cranial cruciate ligament rupture in 28 clinical dogs with unilateral complete rupture and contralateral partial rupture. Three Tesla MRI was performed on 56 stifles using sagittal sequences (T2-weighted fast spin echo with fat saturation, proton density fast spin echo, and T2-weighted 3D fast spin echo CUBE). Two MRI observers assessed the cranial cruciate ligament for fiber loss and completed a visual analog scale. The MRI data were compared to arthroscopy and clinical status. Accuracy classifying partial or complete rupture was assessed using receiver operating characteristic analysis. Compared to arthroscopy, for complete cranial cruciate ligament rupture, sensitivity, specificity, and accuracy of MRI detection of fiber loss were 0.78, 0.50-0.60, and 0.68-0.71, respectively, and, for partial tears, specificity was 1.00. An MRI visual analog scale score ≥79 was indicative of complete cranial cruciate ligament rupture (sensitivity 0.72-0.94 and specificity 0.71-0.84). Using a visual analog scale cut-point ≥79, observers achieved good accuracy discriminating clinical status of partial or complete cranial cruciate ligament rupture (area under the curve 0.87-0.93). MRI evaluation for fiber loss and use of a visual analog scale are specific in stifles with clinically stable partial cranial cruciate ligament rupture. In stifles with clinically unstable complete cranial cruciate ligament rupture, both MRI tests are sensitive though not specific compared to arthroscopy. As a diagnostic imaging method, MRI may help guide treatment in patients with cranial cruciate ligament damage, particularly for stable partial rupture.

A modified tibial compression test for the detection of meniscal injury in dogs

OBJECTIVE

To assess diagnostic efficacy of a modified tibial compression test in predicting medial meniscal injury in dogs with cranial cruciate ligament failure.

METHODS

Dogs admitted for surgical stabilisation of stifles with cranial cruciate ligament failure were examined by five preoperative physical tests to assess medial meniscal injury. Results of each physical test were compared with findings at arthrotomy and used to calculate sensitivities, specificities, positive and negative predictive values.

RESULTS

None of the physical tests were accurate in reflecting meniscal integrity for dogs with cranial cruciate failure. Out of the five tests, the modified tibial compression test exhibited the highest concordance and sensitivity for the detection of medial meniscal tears. A palpable click during the modified tibial compression test had a sensitivity and specificity up to 63 and 77%, respectively, for the detection of medial meniscal lesions. Concordance values were up to 40% for the modified tibial compression test, followed by the range of motion test (up to 25%), while all other physical tests had concordance values below 10%.

CLINICAL SIGNIFICANCE

Physical tests are highly available, affordable and can be easily performed, but their efficacy in diagnosing medical meniscal injury is low. Meniscal clicks associated with meniscal tears were more frequently elicited during the modified tibial compression test when compared with other traditional tests.

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.

Systematic review of the prevalence, risk factors, diagnosis and management of meniscal injury in dogs: Part 2

OBJECTIVE

To systematically evaluate the evidence reporting the diagnosis and management of meniscal injury in dogs with cranial cruciate ligament failure.

STUDY DESIGN

Systematic literature review.

MATERIALS AND METHODS

Research questions relating to the accuracy of diagnostic techniques for meniscal injury and the effects of meniscal treatment were defined. An electronic database search of PubMed and CAB Abstracts was performed during March 2015. 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

Eighty-nine studies were identified. The median Quality Index score was 14 out of a possible 26. Twenty-seven studies were prospective case series, 31 retrospective case series, 16 animal research and 15 cadaveric studies. There were no class I or class II studies, 27 class III and 62 class IV studies.

CONCLUSIONS

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 support one diagnostic or surgical intervention over another for meniscal injuries in dogs with cranial cruciate ligament failure.

Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) stifle joint

Background

The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the stifle joint of a Bengal tiger (Panthera tigris) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images.

Results

MR images showed the bone, articular cartilage, menisci and ligaments of the normal tiger stifle. SE T1-weighted sequence provided excellent resolution of the subchondral bones of the femur, tibia and patella compared with the GE STIR T2-weighted MR images. Articular cartilage and synovial fluid were visualised with high signal intensity in GE STIR T2-weighted sequence, compared with SE T1-weighted sequence where they appeared with intermediate intensity signal. Menisci and ligaments of the stifle joint were visible with low signal intensity in both sequences. The infrapatellar fat pad was hyperintense on SE T1-weighted images and showed low signal intensity on GE STIR T2-weighted images.

Conclusions

MRI provided adequate information of the bony and soft tissues structures of Bengal tiger stifle joints. This information can be used as initial anatomic reference for interpretation of MR stifle images and to assist in the diagnosis of diseases of this region.

Fast presurgical magnetic resonance imaging of meniscal tears and concurrent subchondral bone marrow lesions. Study of dogs with naturally occurring cranial cruciate ligament rupture

Meniscal tears and subchondral bone marrow lesions have both been described in dogs with cranial cruciate ligament rupture, but their possible concurrence has not been evaluated. In a population of 14 dogs exhibiting signs of stifle pain with surgically confirmed cranial cruciate ligament rupture, a short presurgical 1.5T magnetic resonance (MR) imaging protocol including dorsal proton density, dorsal T1-weighted gradient recalled echo, and sagittal fat-saturated dual echo sequences was tested to further investigate these features and illustrate meniscal tears. Interobserver agreement for detection of medial meniscal tears (k=0.83) and bone marrow lesions (k=0.87) was excellent. Consensus MR reading allowed detection of nine out of 12 surgically confirmed medial meniscal tears and there was no false positive. All dogs had cruciate ligament enthesis-related bone marrow lesions in the tibia, femur or both bones. Additionally, among the 12 dogs with confirmed medial meniscal tears, subchondral bone marrow lesions were present in the caudomedial (9 dogs) and caudoaxial (11 dogs) regions of the tibial plateau, resulting in odds ratios (13.6, p=0.12, and 38.3, p=0.04, respectively) that had large confidence intervals due to the small group size of this study. The other two dogs had neither tibial bone marrow lesions in these locations nor medial meniscal tears. These encouraging preliminary results warrant further investigation using this clinically realistic preoperative MR protocol. As direct diagnosis of meniscal tears remained challenging in dogs even with high-field MR, identification of associated signs such as subchondral bone marrow lesions might indirectly allow suspicion of an otherwise unrecognized meniscal tear.

Diagnostic imaging of the canine stifle: a review

The stifle joint, a common location for lameness in dogs, is a complex arrangement of osseous, articular, fibrocartilaginous, and ligamentous structures. The small size of its component structures, restricted joint space, and its intricate composition make successful diagnostic imaging a challenge. Different tissue types and their superimposition limit successful diagnostic imaging with a single modality. Most modalities exploit the complexity of tissue types found in the canine stifle joint. Improved understanding of the principles of each imaging modality and the properties of the tissues being examined will enhance successful diagnostic imaging.