Ultrasound assessment of the posterolateral elbow ulnohumeral gap in normal subjects with and without posterolateral drawer testing.

Background: Posterolateral rotator instability (PLRI) is the most common pattern of recurrent elbow instability, and current imaging to aid PLRI diagnosis is limited. Thus, we sought to define use of ultrasound (US) to determine normal lateral ulnohumeral joint measurements, with and without posterolateral drawer testing to provide an insight into how US may aid diagnosis. Methods: Sixty elbows were evaluated in thirty healthy volunteers. The lateral ulnohumeral gap (LUHG) was measured with US in the resting position while the posterolateral drawer stress test maneuver was applied. Joint laxity was calculated as the difference between maximum stress and average rest measurements. Two independent readers assessed each elbow with comparison performed between stress and rest positions. Results: Differences in the LUHG were evident between stress and rest conditions (reader 1: P < .0001 and reader 2: P = .0002). At rest, median LUHG values were 2.31 mm and 2.05 mm for readers 1 and 2 respectively, while at stress 2.88 mm and 2.9 mm for readers 1 and 2. Median joint laxity was 0.8 mm for reader 1 and 1.1 mm for reader 2. Pearson correlation was r = 0.457 (absolute intraclass correlation coefficient [ICC] = 0.608) while under stress and r = 0.308 (absolute intraclass correlation coefficient [ICC] = 0.417) at rest. Median joint laxity demonstrated a Pearson correlation of r = 0.161 and absolute intraclass correlation coefficient [ICC] = 0.252. Conclusions: This study demonstrates a dynamic US assessment for PLRI, which aimed to assess the usefulness and feasibility of a laxity measurement after the application of a posterolateral drawer stress maneuver in a healthy population. Although establishing concordance between readers in measuring an LUHG under stress, the utility of a laxity measurement alone is not clear as correlation of measurements is not excellent; hence, an upper limit of normal for the ulnohumeral gap under stress may be more useful. Further evaluation of this technique is required in patients with PLRI.

MRI differentiation of low-grade and high-grade chondrosarcoma of the shoulder girdle, chest wall and pelvis: a pictorial review based on 111 consecutive cases.

Approximately 40% of conventional chondrosarcomas arise from the shoulder girdle, chest wall and pelvis. This pictorial review describes the MRI features which may aid in the differentiation of Grade 1 chondrosarcoma (Gd1-CS) from high-grade chondrosarcoma (HG-CS) and dedifferentiated chondrosarcoma (DD-CS) in these locations, based on literature review and assessment of 111 consecutive cases presenting to the senior authors institution over a 13-year period. Of the 111 patients reviewed (71 males and 40 females; mean age 54.3 years; range 17-92 years), 27 were Gd1-CS, 72 were HG-CS and 12 were DD-CS. Tumours arising from the scapula, acetabulum, pubis/ischium and sacrum were more likely to be HG-CS, as were intramedullary tumours. MRI features associated with HG-CS and DD-CS included cortical destruction, bone oedema, soft tissue oedema, tumour necrosis, intermediate T2W SI and joint invasion. The presence of a soft tissue mass became a significant differentiating feature for tumours arising within the medullary cavity, but this was location-specific and did not differentiate between Gd1-CS and HG-CS/DD-CS arising from the sternum or clavicle.

The value of chest and skeletal staging studies in conventional chondrosarcoma.

OBJECTIVE: To determine the value of chest and skeletal staging in patients presenting with conventional chondrosarcoma (CS). MATERIALS AND METHODS: Retrospective review of patients with CS diagnosed between January 2007 and December 2019. Data collected included age, sex, skeletal location and results of chest CT and whole-body bone scintigraphy (WB-BSc) obtained at initial diagnosis. The histological tumour grade based on surgical resection or needle biopsy was classified as low-grade (LGCT), high-grade (HGCT) and dedifferentiated (DD-CS). Findings of chest CT and WB-BSc were correlated with tumour grade. RESULTS: Four hundred twenty patients were included (234 males and 186 females with mean age 54.5 years, range 9-91 years). The major long bones were involved in 205 cases, the flat bones in 166 cases, the mobile spine in 14 cases and the small bones of the hands and feet in 35 cases. Three hundred fifty tumours were central in location, 39 peripheral and 31 on the surface of the bone. There were 151 LGCTs, 196 HGCTs and 73 DD-CSs. Of patients with LGCT, 41.7% underwent chest CT and 25.2% WB-BSc. Of patients with HGCT, 95.4% underwent chest CT and 76.5% WB-BSc. Of patients with DD-CS, 98.6% underwent chest CT and 86.3% WB-BSc. Metastases were diagnosed in 2 (3.3%) chest CT studies and 0 WB-BSc in LGCT, in 8 (4.3%) chest CT studies and 0 WB-BSc in HGCT and in 21 (30%) chest CT studies and 6 (21%) WB-BSc in DD-CS. DISCUSSION: Staging chest CT and WB-BSc is of little or no value except in DD-CS.

The incidence and diagnostic relevance of pathological fracture in conventional central chondrosarcoma.

OBJECTIVE: To determine the incidence and diagnostic relevance of pathological fracture in patients with conventional central chondrosarcoma (CC-CS). MATERIALS AND METHODS: Retrospective review of patients with CC-CS diagnosed between January 2007 and December 2019. Data collected included age, sex, skeletal location and the presence of pathological fracture at presentation. Histological tumour grade based on surgical resection or needle biopsy was classified as atypical cartilaginous tumour (ACT)/grade 1 CS (ACT/Gd1 CS), high-grade CS (HG-CS) and dedifferentiated CS (DD-CS). The presence of pathological fracture was correlated with age, skeletal location and tumour grade. RESULTS: Three hundred seventeen patients were included (177 males and 140 females with mean age 55.8 years, range 9-91 years). Mean age of patients without pathological fracture was 54.4 years and those with pathological fracture 62.9 years (p = 0.002). The major long bones were involved in 171 cases, the flat bones in 112 cases, the mobile spine in 7 cases and the small bones of the hands and feet in 27 cases. There were 81 ACT/Gd 1 CS, 168 HGCS and 68 DD-CS. Pathological fracture was evident at presentation in 51 (16.1%) cases, the commonest bones involved being the femur (n = 21; 41.2%), humerus (n = 10; 19.6%) and acetabulum (n = 7; 13.7%). Pathological facture occurred in 7 cases of ACT/Gd 1 CS (13.7%), 23 cases of HGCS (45.1%) and 21 cases of DD-CS (41.2%) (p = 0.001). Following multivariate analysis, both older age and histological grade were independently significant factors. CONCLUSIONS: Pathological fracture was seen in 16.1% of patients with CC-CS. Pathological fractures in the femur, humerus and acetabulum very likely indicate higher tumour grade.

The importance of MRI review following the diagnosis of atypical cartilaginous tumour using image-guided needle biopsy.

OBJECTIVE: To evaluate the role of pre-biopsy MRI for management planning in patients with atypical cartilaginous tumours (ACT) diagnosed on image-guided core needle biopsy (IGCNB). MATERIALS AND METHODS: Retrospective review of patients diagnosed with ACT of the appendicular skeleton based on IGCNB who subsequently underwent surgical curettage or resection. Data collected included age, sex, skeletal location and surgical histology classified as ACT, high-grade chondrosarcoma (HG-CS) and dedifferentiated chondrosarcoma (DD-CS). Pre-biopsy MRI studies were reviewed independently by 2 radiologists blinded to surgical histology results and graded as ACT, HG-CS and DD-CS based on MRI features. RESULTS: The study included 24 males and 28 females (mean age 42.1 years; range 9-76 years). One patient had 2 lesions treated, making a total of 53 lesions. Tumours were located in the femur in 21 cases, humerus in 17, tibia in 9, radius in 4 and ulna and fibula in 1 each. Surgical histology was ACT in 41 cases, HG-CS in 10 and DD-CS in 2, indicating mismatch between IGCNB and surgical histology in 12/53 cases (22.6%). Predicted MRI grade for the 2 readers was ACT in 39 cases each, HG-CS in 13 and 14 cases and DD-CS in 1 and 0 cases. Sensitivity, specificity and accuracy of MRI for predicting HG-CS/DD-CS were 91%, 93% and 92%, respectively. Inter-observer correlation was very good (kappa = 0.94). DISCUSSION: Review of MRI findings in patients with ACT diagnosed on IGCNB is vital for identifying patients with a HG-CS/DD-CS and is recommended when planning surgical management or considering repeat IGCNB.

Chondral tumours: discrepancy rate between needle biopsy and surgical histology.

OBJECTIVE: To determine the reliability of image-guided core needle biopsy (IGCNB) for the diagnosis and grading of chondral tumours of bone compared with surgical histology. MATERIALS AND METHODS: Retrospective review of patients with a chondral tumour of bone who underwent IGCNB and surgical resection between January 2007 and December 2017. Data collected included age, sex, skeletal location, technique used for IGCNB, IGCNB result including histological grade and comparison with surgical histology. RESULTS: A total of 237 patients were included (135 males and 102 females with mean age 53.7 years, range 9-89 years). A total of 174 IGCNBs were CT-guided, 57 ultrasound-guided and 6 fluoroscopic-guided. Two hundred thirty-six of 237 (99.6%) IGCNBs were diagnostic for a chondral tumour, although grade could not be determined in 13 (5.5%) due to necrosis. A positive correlation for tumour grade between IGCNB and surgical histology was achieved in 181 cases (76.4%). In 36 patients (15.2%), IGCNB under-graded the tumour, while in 6 (2.5%), IGCNB over-graded the tumour. Discrepancy between IGCNB and surgical histology was significantly greater for surface/peripheral lesions (p = 0.02) and lesions arising from the flat bones or spine (p = 0.002). DISCUSSION: IGCNB can achieve a diagnosis of a chondral tumour in a high proportion of cases when compared with final diagnosis from surgical resection specimens. However, correlation of tumour grade between IGCNB and resection histology is less reliable with discordance seen in almost one-quarter of cases, most commonly at non-appendicular sites. Therefore, IGCNB results should not be considered in isolation of imaging and clinical features when planning surgical management.

Anatomic Considerations for Injection of the Lateral Atlanto-Axial Joint.

OBJECTIVE: We aimed to define the potential complications of intra-articular steroid injections into the lateral C1-2 articulations and safety margins to the relevant structures. METHODS: A total of 488 contrast-enhanced computed tomography angiogram (CTA) "arch to vertex" studies were retrospectively reviewed for theoretical intersection of the vertebral artery or thecal sac and distance of the named structures from the anticipated/theoretical trajectory of injection into the lateral C1-C2 joint. RESULTS: Patients were 60.4±15.8 years old and 55.5% male. In total, seven vertebral arteries and 11 thecal sac theoretical intersections were found. In cases without a direct intersection, the distance from the trajectory (range) was 0.71±0.18 (0.22-1.44) cm to the vertebral artery and 0.6±0.22 (0.14-1.8) cm to the thecal sac. CONCLUSIONS: Although injection of steroid into the lateral C1-C2 articulation for pain management has historically been reported to carry risk of severe complications due to close proximity and location variability of surrounding structures, our study quantifies the potential risk of such injections. Further, our analysis suggests that preprocedural imaging should be considered.

Hypertrophic Cardiomyopathy (HCM): New insights into Coronary artery remodelling and ischemia from FFRCT.

INTRODUCTION: Angina, myocardial ischemia, and coronary artery physiology in hypertrophic cardiomyopathy (HCM) are poorly understood. However, coronary computed tomography angiography (CCTA) with fractional flow reserve from CT (FFRCT) analysis offers a non-invasive method for evaluation of coronary artery volume to myocardial mass ratio (V/M) that may provide insight into such mechanisms. Thus, we sought to investigate changes in V/M in HCM. METHODS: A retrospective analysis was performed on 37 HCM patients and 37 controls matched for age, sex, and cardiovascular risk factors; CCTA-derived coronary artery lumen volume (V) and myocardial mass (M) were used to determine V/M. FFRCT values were calculated for the left anterior descending (LAD), left circumflex (LCx) and right coronary (RCA) arteries as well as the 3-vessel cumulative FFRCT values. RESULTS: HCM patients had significantly increased myocardial mass (176 ±â€¯84 vs. 119 ±â€¯27 g, p < 0.0001) and total coronary artery luminal volume (4112 ±â€¯1139 vs. 3290 ±â€¯924 mm3, p < 0.0001) that resulted from increases in segmented luminal volumes of both the left and right coronary artery systems. However, HCM patients had significantly decreased V/M (23.8 ±â€¯5.9 vs. 26.5 ±â€¯5.3 mm3/g; p = 0.026) which was further decreased when restricting V/M analysis to those HCM patients with septal hypertrophy (22.4 mm3/g, p = 0.01) that was mild-moderately predictive of HCM (AUC = 0.68). HCM patients also showed significantly lower nadir FFRCT values in the LCx (0.87 ±â€¯0.06 vs. 0.91 ±â€¯0.06, p = 0.02), and cumulative 3-vessel FFRCT values (2.58 ±â€¯0.18 vs. 2.63 ±â€¯0.14, p = 0.006). CONCLUSIONS: HCM patients demonstrate significantly greater coronary volume. Despite this, HCM patients suffer from decreased V/M. Further prospective studies evaluating the relationship between V/M, angina, and heart failure in HCM are needed.