Upright weight-bearing CT of the knee during flexion: changes of the patellofemoral and tibiofemoral articulations between 0° and 120°

Hirschmann, Anna; Buck, Florian M.; Herschel, Ramin; Pfirrmann, Christian W. A.; Fucentese, Sandro F.

doi:10.1007/s00167-015-3853-8

Cited by 27 publications

(22 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A second validation was performed to increase validity of our FE model further. Patellar position at 0 • , 30 • and 60 • from five upright weight-bearing CT scans of healthy knees were extracted and compared with our simulated patellar positions of the same knees (Hirschmann et al, 2017). The starting position of the patella was hereby determined from the 0 • CT images.…”

Section: Tablementioning

confidence: 99%

Patellofemoral instability in trochleodysplastic knee joints and the quantitative influence of simulated trochleoplasty – A finite element simulation

Kaiser

Trummler

Götschi

et al. 2021

Clinical Biomechanics

Self Cite

View full text Add to dashboard Cite

Background: Patellofemoral instability is a debilitating condition mainly affecting young patients and has been correlated with trochlear dysplasia. It can occur when the patella is insufficiently guided through its range of motion. Currently, there is no literature describing patellofemoral stability in trochleodysplastic knees and the effect of isolated trochleoplasty on patellofemoral stability. Methods: The effect of isolated trochleoplasty in trochleodysplastic knees of patients with symptomatic patellofemoral instability was investigated using a quasi-static finite element model. MRI data of five healthy knees were segmented, meshed and a finite element analysis was performed in order to validate the model. A second validation was performed by comparing simulated patellofemoral kinematics to in-vivo values obtained from upright-weight bearing CT scans. Subsequently, five trochleodysplastic knees were modelled before and after simulated trochleoplasty. The force necessary to dislocate the patella by 10 mm and to fully dislocate the patella was calculated in various knee flexion angles between 0 and 45 •. Findings: The developed models successfully predicted outcome values within the range of reference values from literature. Lateral stability was significantly lower in trochleodysplastic knees compared to healthy knees. Trochleoplasty was determined to significantly increase the force necessary to dislocate the patella in trochleodysplastic knees to comparable values as in healthy knees. Interpretation: This is the first study to investigate lateral patellofemoral stability in patients with symptomatic patellofemoral instability and dysplasia of the trochlear groove. We confirm that patellofemoral stability is significantly lower in trochleodysplastic knees than in healthy knees. Trochleoplasty increases patellofemoral stability to levels similar to healthy.

show abstract

Section: Tablementioning

confidence: 99%

Patellofemoral instability in trochleodysplastic knee joints and the quantitative influence of simulated trochleoplasty – A finite element simulation

Kaiser

Trummler

Götschi

et al. 2021

Clinical Biomechanics

Self Cite

View full text Add to dashboard Cite

show abstract

“…Although the measurements performed at 120° flexion were conducted without WB conditions due to technical limitations, the study reached excellent interreader agreement for most measurements. 54 The internal rotation of the tibia relative to the femur increased alongside the increase of flexion angles, whereas patellofemoral rotation tended to decrease from external to almost horizontal position. TTTG and patellofemoral distance likewise decreased.…”

Section: Kneementioning

confidence: 93%

“…However, regarding the lateral side, the contact point was central (31%-60%) at 0° flexion for most volunteers, gradually shifting to posterior during flexion and located more posteriorly than on the medial side (91%-100%). 54…”

Section: Kneementioning

confidence: 99%

Weight-Bearing Cone Beam Ct Scans and Its Uses in Ankle, Foot, and Knee: An Update Article

Lôbo

Bordalo-Rodrigues

2021

Acta ortop. bras.

View full text Add to dashboard Cite

Imaging plays a key role in the preoperative diagnosis, surgical planning, and postsurgical assessment of the foot, ankle, and knee pathologies. Interpreting diagnostic imaging accurately is crucial for the clinical practice of orthopedic surgeons. Although among the most used imaging modalities, radiographic assessments are amenable to errors for various technical reasons and superposition of bones. Computed tomography (CT) is a conventional imaging procedure that provides high-resolution images, but fails in considering a truly weight-bearing (WB) condition. In an attempt to overcome this limitation, WB cone beam CT technology has being successfully employed in the clinical practice for the past decade. Besides economically viable and safe, the WB cone beam CT considers WB conditions and provides high-quality scans, thus allowing an equitable and correct interpretation. This review aims to address extensive description and discussion on WBCT, including imaging quality; costs; time consumption; and its applicability in common foot, ankle, and knee, conditions. With this technology increasing popularity, and considering the extensive literature on medical research, radiologists and orthopedic surgeons need to understand its potential applications and use it optimally. Level of Evidence III, Systematic review of level III studies.

show abstract

“…New developments in motion correction (11)(12)(13)(14)(15)(16)(17) have enabled imaging of weight bearing subjects with higher image quality. Weight bearing CT has been used previously to detect joint space width (18,19), knee alignment (18,20), and features of osteoarthritis (21) in bones, but examples of measurement of soft tissue morphology in the knee are limited due to difficulties in segmenting soft tissues from CT images. In addition, new methods of assessing cartilage integrity using contrast agent diffusion are being developed (4,5,8,(22)(23)(24)(25)(26)(27).…”

Section: Original Articlementioning

confidence: 99%

Validation of watershed-based segmentation of the cartilage surface from sequential CT arthrography scans

Hall¹,

Black²,

Gold³

et al. 2022

Quant Imaging Med Surg

View full text Add to dashboard Cite

Background: This study investigated the utility of a 2-dimensional watershed algorithm for identifying the cartilage surface in computed tomography (CT) arthrograms of the knee up to 33 minutes after an intraarticular iohexol injection as boundary blurring increased.Methods: A 2D watershed algorithm was applied to CT arthrograms of 3 bovine stifle joints taken 3, 8, 18, and 33 minutes after iohexol injection and used to segment tibial cartilage. Thickness measurements were compared to a reference standard thickness measurement and the 3-minute time point scan.Results: 77.2% of cartilage thickness measurements were within 0.2 mm (1 voxel) of the thickness calculated in the reference scan at the 3-minute time point. 42% fewer voxels could be segmented from the 33-minute scan than the 3-minute scan due to diffusion of the contrast agent out of the joint space and into the cartilage, leading to blurring of the cartilage boundary. The traced watershed lines were closer to the location of the cartilage surface in areas where tissues were in direct contact with each other (cartilage-cartilage or cartilage-meniscus contact). Conclusions:The use of watershed dam lines to guide cartilage segmentation shows promise for identifying cartilage boundaries from CT arthrograms in areas where soft tissues are in direct contact with each other.

show abstract

Upright weight-bearing CT of the knee during flexion: changes of the patellofemoral and tibiofemoral articulations between 0° and 120°

Cited by 27 publications

References 40 publications

Patellofemoral instability in trochleodysplastic knee joints and the quantitative influence of simulated trochleoplasty – A finite element simulation

Patellofemoral instability in trochleodysplastic knee joints and the quantitative influence of simulated trochleoplasty – A finite element simulation

Weight-Bearing Cone Beam Ct Scans and Its Uses in Ankle, Foot, and Knee: An Update Article

Validation of watershed-based segmentation of the cartilage surface from sequential CT arthrography scans

Contact Info

Product

Resources

About