Does the external remote controller's reading correspond to the actual lengthening in magnetic-controlled growing rods?

PURPOSE: Magnetic-controlled growing rods (MCGRs) are now routinely used in many centres to treat early-onset scoliosis (EOS). MCGR lengthening is done non-invasively by the external remote controller (ERC). Our experience suggests that there may be a discrepancy between the reported rod lengthening on the ERC and the actual rod lengthening. The aim of this study was to investigate this discrepancy. METHODS: This was a prospective series. Eleven patients who were already undergoing treatment for EOS using MCGRs were included in this study. RESULTS: One hundred and ninety-two sets of ultrasound readings were obtained (96 episodes of rod lengthening on dual-rod constructs) and compared to their ERC readings. Only 15/192 (7.8%) readings were accurate; 27 readings (14.9%) were false positive; and 8 readings (4.2%) were an underestimation while 142 readings (74.0%) were an overestimation by the ERC. Average over-reporting by the ERC was 5.31 times of the actual/ultrasound reading. When comparing interval radiographs with lengthening obtained on ultrasound, there was a discrepancy with an average overestimation of 1.35 times with ultrasound in our series. There was a significant difference between ERC and USS (p = 0.01) and ERC and XR (p = 0.001). However, there was no significant difference between USS and XR (p > 0.99). CONCLUSION: The reading on the ERC does not equate to the actual rod lengthening. The authors would recommend that clinicians using the MCGR for the treatment of early-onset scoliosis include pre- and post-extension imaging (radiographs or ultrasound) to confirm extension lengths at each outpatient extension. In centres with ultrasound facilities, we would suggest that patients should have ultrasound to monitor each lengthening after distraction but also 6-month radiographs. These slides can be retrieved under Electronic Supplementary Material.

Frequently missed findings in acute ankle injury.

Most acute ankle injuries involve the lateral ligament complex. There are several other structures that can be injured during acute ankle trauma and therefore can be responsible for the patient's acute presentation or for continuing pain. Some of these injuries are less common than others and thus can be more frequently missed during the initial patient presentation. Continued pain and disability following acute ankle trauma that is not responding to routine conservative treatment should alert the clinician and the radiologist for the possibility of injuries other than the common lateral ligament sprain. In this article we describe those injuries that are often overlooked during acute ankle assessment. These include the less common ankle ligaments injuries, fractures, and tendon-related abnormalities.

Femoroacetabular impingement: presence of FAI-like features on conventional radiography in young patients presenting to primary care with hip pain.

BACKGROUND: Femoroacetabular impingement (FAI) is a recognized major cause of early osteoarthritis in the hip and tends to present in young and active patients. The presence of morphological parameters associated with, or predisposing to FAI on radiographs can guide referral to a hip specialist for further assessment. PURPOSE: To determine the presence of radiographic findings with a known association with FAI in young patients presenting to primary care with hip pain. MATERIAL AND METHODS: Retrospective review of 223 consecutive patients presenting with hip pain (age range, 20-40 years) who underwent a pelvic radiograph in a 6-month period. Patients with pre-existing hip disease and/or technically inadequate radiographs were excluded from the study. Radiographs were analyzed for the presence of radiographic signs associated with FAI: acetabular cross-over sign; prominent posterior wall sign; coxa profunda; protrusio acetabula; acetabular index; lateral center edge angle; pistol grip deformity; and herniation pits. RESULTS: Of the initial 223 patients, 33 (17 women, 16 men; age range, 21-40 years; mean age, 33 years) were included in the study after strict application of exclusion criteria. Sixty-four of 66 joints (33/34 [97%] female joints and 31/32 [97%] male joints) had at least one abnormal finding associated with FAI. Forty-three of 66 joints (23/34 [68%] female joints and 20/32 [63%] male joints) had two or more parameters associated with FAI. All of these abnormal radiographs had initially been reported as normal. CONCLUSION: Our study demonstrates a high presence of FAI-like radiographic features in a young symptomatic population; these are often not mentioned in the radiology report.

Cam and pincer femoroacetabular impingement: CT findings of features resembling femoroacetabular impingement in a young population without symptoms.

OBJECTIVE: The purpose of this study was to use CT to determine the presence of radiologic parameters associated with cam and pincer femoroacetabular impingement (FAI) in a young population without symptoms. MATERIALS AND METHODS: A retrospective review of 50 patients (age range, 20-40 years) with no current or previous hip disorder who underwent CT of the abdomen and pelvis was conducted. Multiplanar images were reformatted with a soft-tissue and bone algorithm and assessed for the presence of parameters associated with FAI; alpha angle greater than 55°, femoral head-neck offset less than 8 mm, angle of acetabular version less than 15°, lateral center edge angle greater than 40°, acetabular index less than 0°, pistol-grip deformity, acetabular crossover, and prominent posterior wall signs. RESULTS: At least one abnormal parameter was present in 66% of joints, and two or more abnormal parameters were present in 29% of joints. In seven patients the findings were bilateral. Parameters of mixed morphologic characteristics (cam and pincer) were found in 22% of joints. In side-by-side comparison, high alpha angles were seen in 36 joints measured in the radial plane compared with only three joints measured in the axial oblique plane. CONCLUSION: The CT finding of FAI-like features was made with high frequency in a young symptom-free population. Cutoff values for defining morphologic abnormalities associated with FAI may have been set too low in the current literature. Alpha angle measurements in the radial plane may be a more accurate quantitative assessment of asphericity of the femoral head-neck junction than are measurements in the axial oblique plane.

The association of infrapatellar fat pad oedema with patellar maltracking: a case-control study.

OBJECTIVE: To look for any association between oedema in the superolateral portion of the infrapatellar fat pad and patellar maltracking. MATERIALS AND METHODS: We compared two groups of knee MRI with regard to five patellar maltracking parameters. The first group included 100 knees with evidence of oedema in the superolateral aspect of the infrapatellar fat pad (the study group). The second group included another 100 knee MRI that had a normal infrapatellar fat pad (the control group). The five patellar maltracking parameters assessed were the trochlear depth, tibial tuberosity-trochlear groove distance (TTTG), patellar translation, patellofemoral angle (PFA) and the Insall-Salvati index. RESULTS: There was a statistically significant difference in the Insall-Salvati index, patellar translation and PFA between the two groups (p value of <0.001, <0.001 and 0.004 respectively, Student's t test). There was a higher prevalence of patella alta, lateral patellar displacement (LPD) and lateral patellar tilt in the study group (p value of <0.001, <0.001 and 0.011 respectively, Fisher's exact test). Sixty out of 100 knees in the study group had at least one abnormal patellar maltracking parameter in comparison to 16 out of 100 knees in the control group (p < 0.001, Fisher's exact test). CONCLUSION: Oedema in the superolateral portion of Hoffa's fat pad, the MRI feature of fat pad impingement, is associated with patellar maltracking.

Incidence of pars defects in adolescent idiopathic scoliosis: an MRI study.

OBJECTIVE: In this study, our aim was to present the incidence rate of pars defect in patients with adolescent idiopathic scoliosis, based on MRI findings. METHODS: Two-hundred twenty adolescent idiopathic scoliosis (AIS) patients with MRI scans, taken either as a preoperative investigation or due to other symptoms between 2006 and 2008, were included in the study. The scans were reviewed for pars defect independently by two experienced musculoskeletal radiology consultants. RESULTS: Among the 220 patients, 9 patients (4.09%; 8 female, 1 male) were found to have a pars defect. The mean age of the affected patients was 14 (range: 11-20) years. We noted two lumbar/thoracolumbar curves (Lenke 5), four King Type 1, one King Type 2 and two King Type 3 curves. All scoliotic deformities were non-structural. Bilateral pars defect was noted in eight (89%) of these patients. All of the pars defects were at the L5 vertebral level. CONCLUSION: Our study revealed a 4.09% incidence rate of pars defect in AIS patients which appeared similar to those previously reported in roentgenographic studies.

Persistent ankle pain following a sprain: a review of imaging.

The initial diagnosis of an "ankle sprain" is not always correct. Prolonged pain, swelling and disability sufficient to limit the activity and refractory to treatment following an ankle injury are not typical of an ankle sprain and should alert the clinician of the possibility of an alternative or an associated diagnosis. There are several conditions that can be misdiagnosed as an ankle sprain and those include ankle syndesmosis injuries, sinus tarsi syndrome, ankle and hind foot fractures, osteochondral lesions, posterior tibialis and peroneal tendons abnormalities, spring ligament damage, impingement syndromes and reflex sympathetic dystrophy. In this review, we discuss the imaging features of these conditions that can clinically mimic an ankle sprain. It is crucial to remember that unresolved ankle pain following an injury is not always just due to a "sprain".

Proximal ulna stress fracture and stress reaction of the proximal radius associated with the use of crutches: a case report and literature review.

We report a case of complete stress fracture of the ulna and stress reaction of the radius resulting from the use of crutches in an overweight patient with severe lower extremity arthritis. Plain radiograph showed an undisplaced complete fracture of the proximal metaphysis of the ulna. Magnetic resonance imaging (MRI) was performed to exclude a pathological cause in view of the unusual fracture site, which confirmed the plain radiographic findings and additionally demonstrated a stress reaction in the proximal radius. There are three cases of stress fracture of the ulnar diaphysis resulting from the use of crutches reported previously in the English literature and a further case of bilaterally symmetrical ulnar diaphysial fracture reported in the Danish literature. We report the first case of ulnar metaphysis stress fracture with concomitant stress reaction of the radius.

Hyperdense pericardial effusion in dermatomyositis and contrast induced nephropathy.

Pericardial involvement in dermatomyositis is rare and usually asymptomatic. In many instances, a diagnosis of pericardial involvement is not found until autopsy. Renal failure associated with connective tissue disorders can result in or potentially exaggerate pericardial inflammation. We report an unusual case of high-density pericardial effusion in a patient with dermatomyositis consequent upon contrast nephropathy as demonstrated by computed tomography. High-density pericardial effusion can be a result of an insidious cause such as pericardial inflammation rather than the more usual causes such as coronary or cardiac perforation.

Pseudoaneurysm of the internal mammary artery as an unusual cause of post-sternotomy hemorrhage: the role of multislice computed tomography in the diagnosis and treatment planning.

Pseudoaneurysm of the internal mammary artery (IMA) following median sternotomy is extremely rare. To date, the reported cases are only in single figures. The majority of these pseudoaneurysms were suspected from the clinical presentation, echocardiography or computed tomography (CT) but were only confirmed on contrast angiography. This case report demonstrates the current ability to carry out detailed vascular imaging on a 16-slice CT scanner. This accurate delineation of the pseudoaneurysm allowed targeted therapeutic embolization to be performed without unnecessary angiographic imaging.

Platelet indexes in relation to target organ damage in high-risk hypertensive patients: a substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT).

OBJECTIVES: We sought to investigate the relationship between target organ damage (TOD) in hypertension and a prothrombotic/hypercoagulable state, using a new technique of "platelet lysis" to quantify the amount of P-selectin per platelet (pP-sel), and to correlate it with other platelet markers (e.g., mass, volume and granularity, soluble P-selectin [sP-sel], and beta-thromboglobulin [beta-TG]). BACKGROUND: The increased risk of TOD in hypertension may be related to a prothrombotic/hypercoagulable state, with abnormalities in platelets, such as increased expression of P-selectin. METHODS: We studied 199 patients (mean age 68 years, 75% men) with hypertension. Of these, 125 had TOD (e.g., stroke, previous myocardial infarction, angina, left ventricular hypertrophy). Values obtained were compared with those from 59 healthy normotensive control subjects (mean age 68 years, 58% men). RESULTS: Hypertensive patients had a higher mean platelet volume, mass, pP-sel, sP-sel, and beta-TG and lower platelet granularity (all p < 0.01), but a similar platelet count, as compared with controls. Within the hypertensive group, those with evidence of TOD had significantly larger platelets with greater mass but had lower granularity, sP-sel, and pP-sel levels than those without TOD, possibly reflecting increased aspirin use. On multivariate analysis, aspirin use was a determinant of pP-sel (p = 0.03) and sP-sel (p = 0.01), but the use of other drugs or other co-morbidity (e.g., diabetes, smoking) did not influence either P-selectin value. CONCLUSIONS: Patients with hypertension have evidence of changes in platelet physiology, as reflected by a higher level of pP-sel. Patients with TOD also had larger platelets, with greater mass, and the use of aspirin lowered pP-sel and sP-sel levels. These changes may have implications for the pathophysiology of cardiovascular and cerebrovascular disease in hypertension.

A prospective randomized trial of aspirin-clopidogrel combination therapy and dose-adjusted warfarin on indices of thrombogenesis and platelet activation in atrial fibrillation.

OBJECTIVES: This study was designed to investigate whether or not combination aspirin-clopidogrel therapy would reduce markers of thrombogenesis and platelet activation in atrial fibrillation (AF), in a manner similar to warfarin. BACKGROUND: Dose-adjusted warfarin is beneficial as thromboprophylaxis in AF, but potentially serious side effects and regular monitoring leave room for alternative therapies. METHODS; We randomized 70 patients with nonvalvular AF who were not on any antithrombotic therapy to either dose-adjusted warfarin (international normalized ratio 2 to 3) (Group I) or combination therapy with aspirin 75 mg and clopidogrel 75 mg (Group II). Plasma indices of thrombogenesis (fibrin D-dimer, prothrombin fragment 1+2) and platelet activation (beta-thromboglobulin [TG] and soluble P-selectin) were quantified, along with platelet aggregation responses to standard agonists, at baseline (pretreatment) and at six weeks posttreatment. RESULTS; Pretreatment levels of fibrin D-dimer (p = 0.001), beta-TG (p = 0.01) and soluble P-selectin (p = 0.03) were raised in patients with AF, whereas plasma prothrombin fragment 1+2 levels and platelet aggregation were not significantly different compared with controls. Dose-adjusted warfarin reduced plasma levels of fibrin D-dimer, prothrombin fragment 1+2 and beta-thromboglobulin levels at six weeks (all p < 0.001), enhanced plasma levels of soluble P-selectin (p < 0.001) and had no significant effect on platelet aggregation. Aspirin-clopidogrel combination therapy made no difference to the plasma markers of thrombogenesis or platelet activation (all p = NS), but the platelet aggregation responses to adenosine diphosphate (p < 0.001) and epinephrine (p = 0.02) were decreased. CONCLUSIONS: Aspirin-clopidogrel combination therapy failed to reduce plasma indices of thrombogenesis and platelet activation in AF, although some aspects of ex vivo platelet aggregation were altered. Anticoagulation with warfarin may be superior to combination aspirin-clopidogrel therapy as thromboprophylaxis in AF.