Sub-calcaneal plantar fat pad assessment using dual-energy computed tomography: First experience in the diabetic foot.

BACKGROUND: This study assessed the use of dual-energy computed tomography (CT) to evaluate sub-calcaneal plantar fat pad changes in people with diabetic neuropathy. METHODS: Dual-energy CT scans of people with diabetic neuropathy and non-diabetic controls were retrospectively included. Average CT values (in Hounsfield Units) and thickness (in centimeters) of the sub-calcaneal plantar fat pad were measured in mono-energetic images at two energy levels (40 keV and 70 keV). The CT values measured in patients with diabetic neuropathy were correlated to barefoot plantar pressure measurements performed during walking in a clinical setting. FINDINGS: Forty-five dual-energy CT scans of people with diabetic neuropathy and eleven DECT scans of non-diabetic controls were included. Mean sub-calcaneal plantar fat pad thickness did not significantly differ between groups (diabetes group 1.20 ± 0.34 cm vs. control group 1.21 ± 0.28 cm, P = 0.585). CT values at both 40 keV (-34.7 ± 48.7 HU vs. -76.0 ± 42.8 HU, P = 0.013) and 70 keV (-11.2 ± 30.8 HU vs. -36.3 ± 27.2 HU, P = 0.017) were significantly higher in the diabetes group compared to controls, thus contained less fatty tissue. This elevation was most apparent in patients with Type 1 diabetes. CT values positively correlated with the mean peak plantar pressure. INTERPRETATION: Dual-energy CT was able to detect changes in the plantar fat pad of people with diabetic neuropathy.

The efficacy of flexor tenotomy to prevent recurrent diabetic foot ulcers (DIAFLEX trial): Study protocol for a randomized controlled trial.

Foot ulcers are a frequent and costly problem in people with diabetes mellitus and can lead to amputations. Prevention of these ulcers is therefore of paramount importance. Claw/hammer toe deformities are commonly seen in people with diabetes. These deformities increase the risk of ulcer development specifically at the (tip of) the toe. Percutaneous needle tenotomy of the tendon of the m. flexor digitorum longus (tendon tenotomy) can be used to reduce the severity of claw/hammer toe deformity with the goal to prevent ulcer recurrence. The main objective of this randomized controlled trial is to assess the efficacy of flexor tenotomy to prevent recurrence of toe ulcers in people with diabetes and a history of toe (pre-)ulcers. Additionally, we aim to assess interphalangeal joints (IPJ) and metatarsophalangeal joint (MTPJ) angles in a weight-bearing and non-weight-bearing position, barefoot plantar pressure during walking, cost-effectiveness and quality of life before and after the intervention and compare intervention and control study groups. Sixty-six subjects with diabetes and claw/hammer toe deformity and a recent history of (pre-)ulceration on the tip of the toe will be included and randomized between flexor tenotomy of claw/hammer toes (intervention) versus standard of care including orthosis and shoe offloading (controls) in a mono-center randomized controlled trial. Clinicaltrialsgov registration: NCT05228340.

Preliminary evaluation of dual-energy CT to quantitatively assess bone marrow edema in patients with diabetic foot ulcers and suspected osteomyelitis.

OBJECTIVES: The purpose of this study is to evaluate the value of dual-energy CT (DECT) with virtual non-calcium (VNCa) in quantitatively assessing the presence of bone marrow edema (BME) in patients with diabetic foot ulcers and suspected osteomyelitis. METHODS: Patients with a diabetic foot ulcer and suspected osteomyelitis that underwent DECT (80 kVp/Sn150 kVp) with VNCa were retrospectively included. Two observers independently measured CT values of the bone adjacent to the ulcer and a reference bone not related to the ulcer. The patients were divided into two clinical groups, osteomyelitis or no-osteomyelitis, based on the final diagnosis by the treating physicians. RESULTS: A total of 56 foot ulcers were identified of which 23 were included in the osteomyelitis group. The mean CT value at the ulcer location was significantly higher in the osteomyelitis group (- 17.23 ± 34.96 HU) compared to the no-osteomyelitis group (- 69.34 ± 49.40 HU; p < 0.001). Within the osteomyelitis group, the difference between affected bone and reference bone was statistically significant (p < 0.001), which was not the case in the group without osteomyelitis (p = 0.052). The observer agreement was good for affected bone measurements (ICC = 0.858) and moderate for reference bone measurements (ICC = 0.675). With a cut-off value of - 40.1 HU, sensitivity was 87.0%, specificity was 72.7%, PPV was 69.0%, and NPV was 88.9%. CONCLUSION: DECT with VNCa has a potential value for quantitatively assessing the presence of BME in patients with diabetic foot ulcers and suspected osteomyelitis. KEY POINTS: • Dual-energy CT (DECT) with virtual non-calcium (VNCa) is promising for detecting bone marrow edema in the case of diabetic foot ulcers with suspected osteomyelitis. • DECT with VNCa has the potential to become a more practical alternative to MRI in assessing the presence of bone marrow edema in suspected osteomyelitis when radiographs are not sufficient to form a diagnosis.

Metatarsophalangeal and interphalangeal joint angle measurements on weight-bearing CT images.

BACKGROUND: The aim of this study was to present and evaluate methods of measuring toe joint angels using joint-surface based and inertial axes approaches. METHODS: Nine scans of one frozen human cadaveric foot were obtained using weight-bearing CT. Two observers independently segmented bones in the forefoot and measured metatarsalphalangeal joint (MTPJ) angles, proximal and distal interphalangeal joint (PIPJ and DIPJ) angles and interphalangeal angles of the hallux (IPJ) using 1) inertial axes, representing the long anatomical axes, of the bones and 2) axes determined using centroids of articular joint surfaces. RESULTS: The standard deviations (SD) of the IPJ/PIPJ and DIPJ angles were lower using joint-surface based axes (between 1.5˚ and 4.1˚) than when the inertial axes method was used (between 3.3˚ and 16.4˚), for MTPJ the SD's were similar for both methods (between 0.5˚ and 2.6˚). For the IPJ/PIPJ and DIPJ angles, the width of the 95% CI and the range were also lower using the joint-surface axes method (95% CI: 2.0˚-4.1˚ vs 3.2˚-16.3˚; range: 3.1˚-7.4˚ vs 3.8˚-35.8˚). Intra-class correlation coefficients (ICC) representing inter- and intra-rater reliability were good to excellent regarding the MTPJ and IPJ/PIPJ angles in both techniques (between 0.85 and 0.99). For DIPJ angles, ICC's were good for the inertial axes method (0.78 and 0.79) and moderate for the joint-surface axes method (0.60 and 0.70). CONCLUSION: The joint-surface axes method enables reliable and reproducible measurements of MTPJ, IPJ/PIPJ and DIPJ angles. For PIPJ and DIPJ angles this method is preferable over the use of inertial axes.

It's a thin line: development and validation of Dixon MRI-based semi-quantitative assessment of stress-related bone marrow edema in the wrists of young gymnasts and non-gymnasts.

PURPOSE: To assess reliability and clinical utility of evaluating stress-related metaphyseal water distribution using a semi-quantitative Dixon MRI-based method for early diagnosis of physeal stress injuries in adolescent gymnasts. METHODS: Twenty-four gymnasts with clinically suspected overuse injury of the distal radial physis, 18 asymptomatic gymnasts, and 24 non-gymnast controls aged 12 ± 1.5 years prospectively underwent hand radiographs and 3T MRI of the wrist including coronal T1-weighted and T2-weighted Dixon sequences. Two raters measured metaphyseal water signal fraction in 13 radial and ulnar regions of interest (ROI). Inter- and intrarater reliability, interslice (between 3 middle radial slices), and inter-ROI (between 3 ROIs on same level) reliability were assessed using intraclass correlation coefficients (ICC). Water signal fractions and their within-person ratios in distal versus most proximal ROIs were compared between groups using one-way analysis of variance. RESULTS: Inter- and intrarater ICCs were 0.79-0.99 and 0.94-1.0 for T1-weighted, and 0.88-1.0 and 0.88-1.0 for T2-weighted Dixon. Interslice and inter-ROI ICCs were 0.55-0.94 and 0.95-0.97 for T1-weighted, and 0.70-0.96 and 0.96-0.97 for T2-weighted Dixon. Metaphyseal water signal fraction in symptomatic gymnasts was higher in six distal ROIs compared with asymptomatic gymnasts and in nine ROIs compared with non-gymnasts (p < 0.05). Metaphyseal water score (ratio of distal versus most proximal ROIs) was 1.61 in symptomatic gymnasts and 1.35 in asymptomatic gymnasts on T2-weighted Dixon (p < 0.05). CONCLUSION: Semi-quantitative Dixon MRI-based water signal fraction assessment has good to excellent reproducibility and shows increased metaphyseal water scores in symptomatic gymnasts compared with asymptomatic gymnastic peers. KEY POINTS: • The proposed Dixon MRI-based semi-quantitative method for assessment of metaphyseal bone marrow water content is reliable, with off-the-shelf availability and short scan times. • The metaphyseal water score allows comparisons between gymnasts using a within-person reference area for unaffected metaphyseal bone. • As metaphyseal water score was increased in symptomatic gymnasts compared with asymptomatic gymnasts, this semi-quantitative method can potentially be used as an indicator of bone marrow edema in the early diagnosis of gymnastic physeal stress injury.

A core questionnaire for the assessment of patient satisfaction in academic hospitals in The Netherlands: development and first results in a nationwide study.

BACKGROUND: Patient satisfaction is one of the relevant indicators of quality of care; however, measuring patient satisfaction had been criticised. A major criticism is that many instruments are not reliable and/or valid. The instruments should have enough discriminative power for benchmarking of the results. OBJECTIVE: To develop a "core questionnaire for the assessment of patient satisfaction in academic hospitals" (COPS) that is reliable and appropriate for benchmarking patient satisfaction results. RESEARCH DESIGN: The development of COPS, the testing of its psychometric quality and its use in eight Dutch academic hospitals in three national comparative studies in 2003, 2005 and 2007 are described in this study. Results were reported only if they were significant (p<0.05) and relevant (also Cohen d>0.2). RESULTS: The questionnaire was returned in 2003 by 40,678 patients (77,450 sent, 53%) and by 40,248 patients (75,423 sent, 53%) in 2005. In 2007, the questionnaire was returned by 45,834 patients (87,137, 53%). The six dimensions have good Cronbach α's, varying from 0.79 to 0.88.The results of every item were reported to the individual hospital. A benchmark overview showed the overall comparison of all specialties of the eight hospitals for the clinic and outpatient departments. The 2007 measurement showed relevant differences in satisfaction on two dimensions in the clinical setting. CONCLUSIONS: COPS is shown to be a feasible and reliable instrument to measure the satisfaction of patients in Dutch academic hospitals. It allows comparison of hospitals and gives benchmark information on a hospital as well as data on specialty levels and previous measurements, including best practices.