Melorheostosis: A Pediatric Case of a Rare Association With Carpal Tunnel Syndrome.

Melorheostosis is a rare chronic disease commonly affecting long bones of the lower extremity with the typical imaging feature of hyperostosis "candle wax pattern." Typically associated with pain, deformities, stiffness, and joint movement restriction (due to contracture and fibrosis), it may also be asymptomatic. Melorheostosis is considered a benign disease but can be extremely debilitating, especially in a pediatric context where progression can be faster than in adults. An even rarer occurrence seems to be its association with nerve impingement. In this paper, we present the case of an 8-year-old girl with a known condition of melorheostosis of the upper limbs who developed bilateral carpal syndrome. To our knowledge, very few cases of the sort have been described, and even less in a pediatric context.

Osteonecrosis of the Lunate Following Three-Corner Arthrodesis: A Case Report.

Scaphoid lunate advanced collapse (SLAC) is the most frequently encountered cause of wrist osteoarthritis. Proximal row carpectomy (PRC) and four-orner arthrodesis (4CA) are the two main surgical options to address it. Three three-corner arthrodesis (3CA) was introduced in 1997 as an alternative to PRC and 4CA. It is a motion preserving midcarpal arthrodesis easier to perform than 4CA, for which the literature has documented satisfactory outcomes and low complication rates. We report a case of a SLAC wrist treated with 3CA complicated by postoperative osteonecrosis of the lunate. To our knowledge, this complication has not been previously reported. Our patient developed osteonecrosis of the lunate 1 year after 3CA despite a good consolidation of the arthrodesis. In this case study, we discuss reasons this may have occurred, the aetiology of which is likely multifactorial. We are reporting this case to inform surgeons of this potential complication after 3CA. Level of Evidence: Level V (Therapeutic).

Atlas of Sonographic Anatomy of the Hand and Wrist.

Accurate knowledge of the technique of ultrasonographic (US) examination and of normal US appearance is a prerequisite for a successful US examination of the wrist and hand. In this article, we describe our standard US examination as well as the normal US findings of the hand and wrist.

Sonographic and radiographic evaluation of the extensor tendons in early postoperative period after total knee arthroplasty.

OBJECTIVE: To prospectively assess the early changes in the quadriceps and patellar tendons before and after total knee arthroplasty using ultrasound, shear wave elastography, and X-rays. MATERIALS AND METHODS: Radiographs, ultrasound, and shear wave elastography were performed on 23 patients (16 women; aged 51-85, mean 66 ± 9 years) before and after surgery at 6 weeks and on 11 patients at 3 months. Patellar position and patellar tendon lengths were evaluated by radiography; joint effusion or synovitis, quadriceps and patellar tendon lengths, and thicknesses, echogenicity, vascularity, and stiffness were assessed with ultrasound and shear wave elastography. RESULTS: In the early postoperative period, 87% of the patients had joint effusion, and 43% had signs of synovitis. There was a significant thickening of the quadriceps tendon in 51.5% (p < .0001) and of the patellar tendon in 93.8% (p < .0001) of patients with a significant shortening of the patellar tendon in 7.8% (p < .0001). A hypoechoic defect on the medial aspect of the quadriceps tendon was found in 87% of the patients. There was a significant increase in Young's modulus in the quadriceps tendon (p = .0006) but not in the patellar tendon. CONCLUSION: The following should not be considered to be pathological findings at early postoperative imaging: joint effusion, synovitis, increasing of stiffness and thickening of quadriceps tendons by more than 50%, thickening of patellar tendon by more than 90%, focal defect through the medial aspect of the quadriceps tendon, and shortening of the patellar tendon by 8%.

Prevalence and frequency of subchondral bone marrow edema in the lumbar facet joints of asymptomatic and symptomatic individuals.

OBJECTIVE: To prospectively compare the prevalence and frequency of subchondral bone marrow edema (BME) in the lumbar facet joints of low back pain patients and healthy subjects. MATERIALS AND METHODS: Lumbar magnetic resonance imaging (MRI) examinations were performed on 55 asymptomatic participants (18 men; age range 21-63; mean 36 ± 12 years; body mass index (BMI) range 16-31; mean 22.6 ± 3.2 kg/m2) and 79 low back pain patients (36 men; age range 18-77; mean 47 ± 14 years; BMI range 18-40; mean 27.8 ± 4.4 kg/m2). In both groups, facet joint subchondral BME signal was evaluated using T2-weighted STIR imaging, and facet joint osteoarthritis was characterized as mild, moderate, and severe. RESULTS: The BME signal was found in seven asymptomatic participants (12.7%) and 28 low back pain patients (35.4%) (P = 0.003). A significant portion of the patients (15.2%) presented more than one BME signal (P = 0.011). By pooling the ten facet joints of all subjects in each group, a significant difference in osteoarthritis grade distribution was observed between the two groups (P < 0.001). When adjusted for low back pain status, age, BMI, Modic type 1, disk herniation, and facet joint osteoarthritis maximal grade, only the latter was significantly associated with the facet joint BME signal (P < 0.001). CONCLUSION: Despite the higher prevalence and frequency of the BME signal in facet joints of low back pain patients compared to that in healthy subjects, the signal was found to be associated with the severity of the patients' osteoarthritis and not with their low back pain status.

Sonography of the Pronator Teres: Normal and Pathologic Appearances.

The pronator teres muscle is rarely examined during a routine sonographic examination of the elbow joint. Nevertheless, it can be affected by a variety of conditions, including trauma and tumors, and can be implicated in compression of the median nerve. This pictorial essay first illustrates the anatomy and biomechanics of the pronator teres. Then we present the sonographic technique for examination, normal sonographic appearance, and anatomic variations of the pronator teres and adjacent structures as well as sonography of their main disorders. Normal and pathologic sonographic appearances are correlated with magnetic resonance imaging and radiographic results.

Nerves Around the Shoulder: What the Radiologist Should Know?

Peripheral neuropathies of the shoulder are common and could be related to traumatic injury, shoulder surgery, infection or tumour but usually they result from an entrapment syndrome. Imaging plays an important role to detect the underlying causes, to assess the precise topography and the severity of nerve damage. The key points concerning the imaging of nerve entrapment syndrome are the knowledge of the particular topography of the injured nerve, and the morphology as well signal modifications of the corresponding muscles. Magnetic Resonance Imaging best shows these findings, although Ultrasounds and Computed Tomography sometimes allow the diagnosis of neuropathy.

Pulmonary emphysema: effect of lung volume on objective quantification at thin-section CT.

PURPOSE: To prospectively investigate the effect of submaximal inspiration on computed tomographic (CT) indexes used to quantify emphysema and to discriminate between effects of lung tissue loss and increase in total lung capacity (TLC) on these indexes. MATERIALS AND METHODS: In this ethical committee-approved study, 20 control subjects and 16 patients with chronic obstructive pulmonary disease (COPD) who provided written informed consent were included. Three 1-mm-thick sections were obtained from each participant at 100%, 90%, 80%, 70%, and 50% of vital capacity (VC). At each volume, eight percentiles of attenuation distribution, as well as relative area (RA) of lung occupied by attenuation coefficients lower than nine thresholds, were calculated. A linear regression line between TLC and each CT index was plotted for control subjects. Mean distance from data points measured in patients with COPD to the normal regression line was used to reflect the effect of lung tissue loss, regardless of TLC. RESULTS: The RA of lung occupied by attenuation coefficients lower than -950 HU (RA(950)) at any percentage of VC lower than 100% decreased significantly from that at 100% VC (P ≤ .002) in control subjects and patients with COPD; however, between 100% VC and 90% VC, the average difference in RA(950) was only 3% and 2% in control subjects and patients with COPD, respectively. The 1st percentile at any percentage of VC lower than 100% increased from that at 100% VC (P < .001) in control subjects. This percentile did not significantly differ from 100% VC at 90% VC or 80% VC (P = .176 and P = 0.077, respectively), but it did significantly differ from 100% VC at 70% VC and 50% VC (P ≤ .002 for both) in patients with COPD. Slope and mean distance were different from zero for all RAs and percentiles except for mean distance for RAs between RA(900) and RA(920). CONCLUSION: Submaximal inspiration induces underestimation of pulmonary emphysema. Both lung tissue loss and TLC influence CT indexes, suggesting the need to establish normal CT values.

Pulmonary emphysema: size distribution of emphysematous spaces on multidetector CT images--comparison with macroscopic and microscopic morphometry.

PURPOSE: To test the hypothesis that the frequency-size distribution of low-attenuation areas could be a parameter to quantify pulmonary emphysema. MATERIALS AND METHODS: Ethics committee approval and written informed consent were obtained. Multidetector computed tomographic (CT) scans were performed with simultaneous acquisition of four 1-mm sections of the whole chest in 80 patients (57 men, 23 women; age range, 38-79 years) who were referred for surgical resection of lung cancer. From the raw data, 1.25-mm-thick sections were reconstructed at 10-mm intervals. The relative area of lung with attenuation coefficients lower than -960 HU (RA(960)) and the 1st percentile of the distribution of attenuation coefficients were calculated. The cumulative frequency-size distributions of the RA(960) and the 1st percentile, when represented on a log-log plot, followed linear relationships. The slopes of these lines (D(960) and D(p1)) were compared with areas found macroscopically to have emphysema and with two different microscopic measurements assessed on resected specimens. Spearman correlation coefficients of each CT index with macroscopic and microscopic measurements were calculated. RESULTS: The RA(960) and the 1st percentile showed statistically significant correlations with macroscopic and microscopic indexes (P < .001), whereas D(960) and D(p1) did not (P > or = .165). CONCLUSION: The RA(960) and the 1st percentile reflect the extent of emphysema as compared to macroscopic and microscopic measurements, while D(960) and D(p1) do not.

Pulmonary emphysema: radiation dose and section thickness at multidetector CT quantification--comparison with macroscopic and microscopic morphometry.

PURPOSE: To prospectively investigate the effects of radiation dose and section thickness on quantitative multidetector computed tomographic (CT) indexes of pulmonary emphysema. MATERIALS AND METHODS: The institutional review board approved this protocol. Written informed consent was obtained from all patients. Seventy patients (49 men, 21 women; age range, 38-79 years) referred for surgical resection of a lung tumor underwent multidetector CT with 4 x 1-mm collimation, 120 kVp, and 20 and 120 effective mAs. At each radiation dose, 1.25-, 5.0-, and 10.0-mm-thick sections were reconstructed at 10-mm intervals. From scans of the lobe or whole lung to be resected, relative areas (RAs) of lung with attenuation coefficients lower than nine thresholds and eight percentiles of the distribution of attenuation coefficients were compared with the histopathologic extent of emphysema, which was measured microscopically--by using the corrected mean interwall distance (MIWD) and the corrected mean perimeter (MP)--and macroscopically. Correlations between the data obtained by using attenuation thresholds and percentiles and the parameters macroscopic extent of emphysema, MIWD, and MP were investigated by using Spearman coefficients. RESULTS: The 1st percentile (r range, -0.394 to -0.675; P < .001) and attenuation coefficients of -980, -970, and -960 HU (r range, 0.478-0.664; P < .001) yielded the strongest correlations with macroscopic extent, MIWD, and MP, regardless of radiation dose or section thickness. The effects of radiation dose and section thickness on RAs of lung with attenuation coefficients lower than -960 HU (P = .007 and P < .001, respectively) and lower than -970 HU (P = .001 and P < .001, respectively) were significant. The effect of section thickness on the 1st percentile was significant (P < .001), whereas the effect of dose was not (P = .910). CONCLUSION: At CT quantification of pulmonary emphysema, the tube current-time product can be reduced to 20 mAs, but both tube current-time product and section thickness should be kept constant in follow-up examinations.

Pulmonary emphysema: objective quantification at multi-detector row CT--comparison with macroscopic and microscopic morphometry.

PURPOSE: To prospectively compare pulmonary function tests and helical computed tomographic (CT) indexes for quantifying pulmonary emphysema with macroscopic and microscopic morphometry. MATERIALS AND METHODS: The investigation was approved by the local ethics committee, and written informed consent was obtained from patients. Multi-detector row CT of the thorax was performed with simultaneous acquisition of four 1-mm sections in 80 patients (57 men, 23 women; age range, 38-79 years) referred for surgical resection of lung cancer. From the raw data, 1.25-mm-thick sections were reconstructed at 10-mm intervals. Relative areas of lung with attenuation coefficients lower than nine thresholds and eight percentiles of the distribution of attenuation coefficients were calculated. Relative areas and percentiles were compared with areas found macroscopically to have emphysema and with two microscopic indexes assessed on resected specimens. Pulmonary function tests were measured 24-48 hours before surgery. Spearman correlation coefficients were calculated between each set of CT data obtained with the nine tested thresholds and eight percentiles with macroscopic and microscopic measurements. RESULTS: For relative lung areas, the strongest correlation with macroscopy was observed with a threshold of -970 HU (r = 0.543, P < .001) and that with microscopy was observed at -960 and -970 HU, depending on the index considered (r = 0.592, P < .001 and r = -0.546, P < .001, respectively). For percentiles, 1st percentile showed the strongest correlation with both macroscopy (r = -0.463, P < .001) and microscopy (r = -0.573, P < .001; and r = 0.523, P < .001 for each microscopic measurement). Forced expiratory volume in 1 second and vital capacity ratio, diffusing capacity of lung for carbon monoxide, and each of the three CT indexes were complementary to predict microscopic indexes. CONCLUSION: Relative lung areas with attenuation coefficients lower than -960 or -970 HU and 1st percentile are valid indexes to quantify pulmonary emphysema on multi-detector row CT scans.

CT quantification of pulmonary emphysema: assessment of lung structure and function.

Accurate diagnosis and quantification of pulmonary emphysema in vivo is important to understand the natural history of the disease, to assess the extent of the disease, and to evaluate and follow-up therapeutic interventions. Because pulmonary emphysema is defined by pathology, new diagnostic methods for quantification should be validated by reference to pathological and histological standards. Recent studies have addressed the capability of computed tomography (CT) to accurately quantify pulmonary emphysema. These studies that have been overviewed in this article have been based on CT scans obtained after deep inspiration or expiration, on subjective visual grading, and on objective measurements of attenuation values by using dedicated software providing numerical data on two-dimensional and on three-dimensional approaches, and compared CT data with pulmonary function tests. More recently, fractal and textural analyses were applied to CT scans to assess the presence, extent, and types of emphysema. Quantitative CT has already been used in patient selection for surgical treatment of pulmonary emphysema and in pharmacotherapeutical trials. However, despite numerous and extensive studies already available, this technique has not yet been standardized, and important questions about how to best use CT for the quantification of pulmonary emphysema remain to be addressed.