Technique of Torsion Measurement of the Lower Extremity Using Computed Tomography

Widjaja, P. M.; Ermers, J. W. L. M.; Sijbrandij, S; Damsma, H.; Klinkhamer, Adrianus C.

doi:10.1097/00004728-198505000-00009

Cited by 21 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To date, computed tomography (CT) is considered the gold standard for the clinical workup of lower extremity malalignment [ 9 – 11 ]. Non-contrast-enhanced CT is widely available, fast, and cost-effective compared to other methods such as magnetic resonance imaging (MRI).…”

Section: Introductionmentioning

confidence: 99%

Diagnostic accuracy of ultra-low-dose CT for torsion measurement of the lower limb

et al. 2020

View full text Add to dashboard Cite

Objectives The study aimed to investigate the diagnostic performance of simulated ultra-low-dose CT (ULD-CT) for torsion measurement of the lower limb. Methods Thirty retrospectively identified patients were included (32.3 ± 14.2 years; 14 women, 16 men). ULD-CT simulations were generated at dose levels of 100%, 10%, 5%, and 1% using two reconstruction methods: standard filtered back projection (FBP) and iterative reconstruction (ADMIRE). Two readers measured the lower limb torsion in all data sets. The readers also captured image noise in standardized anatomical landmarks. All data sets were evaluated regarding subjective diagnostic confidence (DC; 5-point Likert scale). Effective radiation dose of the original data sets and the simulated ULD-CT was compared. Results There was no significant difference of measured lower limb torsion in any simulated dose level compared to the original data sets in both readers. Dose length product (DLP) of the original examinations was 402.1 ± 4.3 mGy cm, which resulted in an effective radiation dose of 4.00 ± 2.12 mSv. Calculated effective radiation dose in ULD-CT at 1% of the original dose was 0.04 mSv. Image noise increased significantly with dose reduction (p < 0.0001) and was dependent on the reconstructional method (p < 0.0001) with less noise using ADMIRE compared to FBP. Both readers rated DC at doses 100%, 10%, and 5% with 5.0/5: there were no ratings worse than 3/5 at 1% dose level. Conclusions The results suggest that radiation dose reduction down to 1% of original CT dose levels may be achieved in CT torsion measurements of the lower limb without compromising diagnostic accuracy. Key Points • Modern CT delivers exceptional high image quality in musculoskeletal imaging, especially for evaluation of osseous structures. • Usually, this high image quality is accompanied by significant radiation exposure to the patient and may not always be required for the intended purpose, e.g., pure delineation of cortical bone of the lower limb. • This study shows the tremendous prospects of radiation dose reduction without compromising diagnostic confidence in CT torsion measurement of the lower limb.

show abstract

Section: Introductionmentioning

confidence: 99%

Diagnostic accuracy of ultra-low-dose CT for torsion measurement of the lower limb

et al. 2020

View full text Add to dashboard Cite

show abstract

“…The validity of CT measurements of tibial torsion was determined in cadaveric studies [3,11]. Its use has been advocated in numerous studies [2,3,7,11,12,25]. Other methods such as MRI [17,18,24] and ultrasound [2,10] also are valid tools for measuring the level of tibial torsion and can be used as reference standards.…”

Section: Discussionmentioning

confidence: 99%

Tibial Torsion in Cerebral Palsy: Validity and Reliability of Measurement

Lee¹,

Chung²,

Park

et al. 2009

Clinical Orthopaedics &Amp; Related Research

View full text Add to dashboard Cite

Physical examinations of tibial torsion are used for preoperative planning and to assess outcomes of tibial osteomy in patients with cerebral palsy (CP). The thigh-foot angle (TFA) and transmalleolar axis (TMA) are commonly used, and the second toe test recently was introduced. However, the validity and reliability of the three methods have not been clarified. This study was performed to evaluate the validity and reliability of these physical measures. We recruited 18 patients (36 limbs) with CP. During reliability sessions, three raters with various levels of orthopaedic experience independently measured tibial torsion using the three different methods during one day before surgery. Validity was assessed by performing a correlation study between physical examination and two-dimensional computed tomographic (CT) findings. Interobserver reliability was greatest for the TMA followed by TFA and then by the second toe test with intraclass correlation coefficients of 0.92, 0.74, and 0.57, respectively. In terms of the concurrent validity, the correlation coefficients (r) for the CT measurements were 0.62, 0.52, and 0.55. When depicting tibial torsion by physical examination, all three methods had substantial validity, but test reliability and validity were highest for TMA measurements.

show abstract

“…Furthermore, in the present review, data describing the levels of the slices and anatomical landmarks used to create the condylar axis are lacking, thus making it difficult to draw any recommendations. 58 In the literature, other techniques using 2D CT have been proposed, reflecting the difficulty of using axial scan slice(s) to define accurately the landmarks needed to determine the 'femoral neck line' 46,58,[60][61][62][63] (see Fig. 2) and the condylar line.…”

Section: Femoral Anteversionmentioning

confidence: 99%

Validity and reliability of radiological methods to assess proximal hip geometry in children with cerebral palsy: a systematic review

Pons

Rémy-Néris

Médée

et al. 2013

Develop Med Child Neuro

View full text Add to dashboard Cite

AIM The aim of this systematic review was to assess the current validity and reliability of radiological methods used to measure proximal hip geometry in children with cerebral palsy.METHOD A search was conducted using relevant keywords and inclusion/exclusion criteria of the MEDLINE, CINALH Plus, Embase, Web of Science, Academic Search Premier, The Cochrane Library, and PsychINFO databases. RESULTSThe migration percentage using X-rays showed excellent reliability and concurrent validity with three-dimensional (3D) measurements from computed tomography (CT) scans. The acetabular index, measured using X-rays had good reliability but moderate concurrent validity with 3D CT measurements; 3D CT scan indexes had greater reliability. The measurement of the neck shaft angle using X-rays showed excellent concurrent validity with measurements from 3D CT scans and excellent reliability. Regarding femoral anteversion, one study found an excellent correlation between two-dimensional CT and clinical assessment and excellent reliability. Two others showed less evidence for the use of CT ultrasounds.INTERPRETATION Most of the X-ray-based measurements showed good to excellent metrological properties. More metrological evidence is needed for the assessment of femoral anteversion. Magnetic resonance imaging and ultrasound-based measurements have great potential although very little metrological evidence is available.Hip deformities occur in over one-third of children with cerebral palsy (CP) and are the second most common musculoskeletal deformity after equinus.

show abstract

Technique of Torsion Measurement of the Lower Extremity Using Computed Tomography

Cited by 21 publications

References 0 publications

Diagnostic accuracy of ultra-low-dose CT for torsion measurement of the lower limb

Diagnostic accuracy of ultra-low-dose CT for torsion measurement of the lower limb

Tibial Torsion in Cerebral Palsy: Validity and Reliability of Measurement

Validity and reliability of radiological methods to assess proximal hip geometry in children with cerebral palsy: a systematic review

Contact Info

Product

Resources

About