The use of the flow-void sign on MRI: highly sensitive sign in detecting bone metastases from renal cell carcinoma

OBJECTIVE

To evaluate a range of pathologically proven malignant bone tumours, including primary bone sarcoma and metastatic bone lesions, referred to a tertiary referral centre for the presence of the flow-void sign on MR imaging.

MATERIALS AND METHODS

A retrospective search was performed using the radiology information system and oncology database in our institution to identify patients over the age of 40 years referred with a solitary bone lesion. Patients with a range of pathologically proven malignant bone tumours, including primary bone tumours and metastatic bone lesions, were included in the study. MRI images were reviewed for the presence of the flow-void sign. The presence and type of the flow-void sign were correlated with lesion size.

RESULTS

Two hundred and sixty-six cases were included in the study. Overall, the flow-void sign was identified in 40.9% of cases. The flow-void sign was most frequently seen in renal cell carcinoma metastasis (90.0%). The sign is highly sensitive (90%) for renal cell carcinoma metastases with a high negative predictive value (98.09%). When the flow-void sign is identified, the lesion is almost three times more likely to represent a renal cell carcinoma metastasis than any other malignant tumour in patients over the age of 40 years with a solitary bone lesion.

CONCLUSION

The flow-void sign is highly sensitive for renal cell carcinoma bone metastases and could negate the need for biopsy in patients with a known history of renal cell carcinoma or in whom an occult renal cell carcinoma is subsequently identified.

Radiological angle assessment of Haglund's deformity: validation on Magnetic Resonance Imaging

PURPOSE

Haglund's deformity, an abnormality at the postero-superior corner of the calcaneus is a common cause of posterior heel pain. To date numerous measurements of radiological angles related to the calcaneus have been proposed to differentiate between symptomatic and asymptomatic patients with the deformity. Traditionally, these measurements have been assessed on plain radiographs. The aim of this study was to identify measurements which can be applied to Magnetic Resonance Imaging (MRI) studies of the ankle.

METHODS

A retrospective cohort analysis of 30 MRI ankle studies from patients with symptomatic Haglund's deformity and 32 normal studies as controls was undertaken. The angle of BRINK, the Achilles angle, Calcaneal pitch, Achilles-plantar fascia angle and soleus calcaneal distance were measured on optimal T2 fat-saturated sagittal slices.

RESULTS

There was a statistically significant difference (p < 0.0001) in the angle of BRINK between the Haglund's and control group. The Area-Under-the-Curve (AUC) was 0.7783 in keeping with good discrimination between the two groups. The angle of BRINK measurement is reproducible, with an intra-observer ICC of 0.837 and an inter-observer ICC of 0.824. There was no statistically significant difference between the two groups for the other measurements. In the Haglund's group the Achilles tendon was more likely to attach to the mid 1/3 of the posterior calcaneus as opposed to the superior 1/3 (p = 0.02), calcaneal oedema was more likely to be present (p < 0.001) and non-insertional tendinopathy was more likely to be present (p < 0.001). The presence of a retrocalcaneal bursa is non-specific (p = 0.602).

CONCLUSION

The angle of BRINK demonstrates good discrimination between normal and Haglund's cases on MRI studies and may improve patient management by supporting surgical decision-making. Future work should correlate the angle of BRINK to long-term outcomes.

The clinical significance of indeterminate pulmonary nodules in patients with primary bone sarcoma: a systematic review

OBJECTIVE

To report the incidence of indeterminate pulmonary nodules (IPN) and the rate of progression of IPNs to metastasis in patients with primary bone cancers. We also aimed to evaluate clinical or radiological parameters that may identify IPNs more likely to progress to metastatic disease and their effect on overall or event-free survival in patients with primary bone sarcoma.

METHODS

A systematic search of the electronic databases Medline, Embase, and Cochrane Library was undertaken for eligible articles on IPNs in patients with primary bone sarcomas, published in the English language from inception of the databases to 2023. The Newcastle-Ottawa Quality Assessment Form for Cohort Studies was utilized to evaluate risk of bias in included studies.

RESULTS

Six studies, involving 1667 patients, were included in this systematic review. Pooled quantitative analysis found the rate of incidence of IPN to be 18.1% (302 out of 1667) and the rate of progression to metastasis to be 45.0% (136 out of 302). Nodule size (more than 5 mm diameter), number (more than or equal to 4), distribution (bilaterally distributed), incomplete calcification, and lobulated margins were associated with an increased likelihood of IPNs progressing to metastasis, however, their impact on overall or event-free survival remains unclear.

CONCLUSION

The risk of IPNs progressing to metastasis in patients with primary bone sarcoma is non-negligible. Large IPNs have a high risk to be an actual metastasis. We suggest that IPNs in these patients be followed up for a minimum of 2 years with CT imaging at 3, 6, and 12 month intervals, particularly for nodules measuring >5 mm in average diameter.

ADVANCES IN KNOWLEDGE

This is the first systematic review on IPNs in patients with primary bone sarcomas only and proposes viable management strategies for such patients.

The T1 Ratio of Marrow (TROM) as a Novel Tool to Identify Metastatic from Nonmalignant Marrow Lesions of the Spine: A Pilot Study

Objective  The purpose of this study was to analyze quantitative values of normal and abnormal marrow on T1-weighted images of spine, to propose a ratio for T1 values of abnormal to normal vertebrae, and to assess whether this ratio could be helpful in predicting presence of neoplastic lesions in the spine. Materials and Methods  One-hundred randomly selected magnetic resonance imagings of lumbar spine without infection, fracture, and tumor were selected to form normal cohort. A second cohort of 100 metastasis of lumbar spine was identified. Ratio of T1 value of vertebral body to the T1 value of the inferior vertebral body was performed for normal cohort from D11 to L5. Ratio of T1 value of metastasis to adjacent normal vertebral body was done for metastatic cohort. Data was analyzed using standard t -test and kappa was performed for intra- and inter-observer reliability. Results  A decline in T1 value of abnormal to normal marrow was seen in patients with metastasis that was statistically significant. We call this the T1 ratio of marrow (TROM). The sensitivity and accuracy with the cutoff value of TROM at 0.7 (92% sensitivity, 97.1% accuracy) are better than at 0.6 (75% sensitivity, 96.2% accuracy) or 0.5 (47% sensitivity, 93.2% accuracy). A subset analysis of the other T1 hypointense benign lesions including atypical hemangiomas and focal marrow hyperplasia, however, revealed overlapping TROM values with the metastatic cohort. Conclusion  Using the TROM on T1-weighted images could not confidently differentiate malignant from benign T1 hypointense lesions of the spine.

Does Chemical Shift Magnetic Resonance Imaging Improve Visualization of Pars Interarticularis Defect?

Introduction A unilateral or bilateral pars interarticularis defect (spondylolysis) is a leading cause of axial back pain in adolescent athletes. Currently, a spectrum of imaging modalities is used for assessment of pars interarticularis defects.

Objectives The aim of this study is to compare the accuracy of chemical shift sequence (magnetic resonance imaging [MRI]) technique to conventional MRI sequences in the detection of pars defects.

Patients and Methods Conventional T1, T2, and short tau inversion recovery sagittal and axial, as well as “in-” and “out-” phase chemical shift sagittal MRI sequences of 70 consecutive patients referred for low back pain were reviewed. Demographic details, clinical indication, and presence/diagnosis of pars defects using a 5-point Likert scale on both conventional and chemical shift MRI sequences. Spearman's correlation was used for statistical analysis. Intraclass correlation coefficient analysis was evaluated to assess the intraclass reliability between observers. Data were analyzed using DATAtab web-based statistics software (2022).

Results A total of 70 patients with an average age of 54.34 years with a female predominance were included. There were 11 pars defects in the cohort. Both in and out phases of chemical shift imaging were able to identify pars defect and intact pars. However, out phase was relatively better in delineating pars defects, while the in phase was superior in identifying an intact pars, though this was not statistically significant. There was good intra- and interobserver reliabilities.

Conclusion Chemical shift MRI sequence is a quicker, complementary technique to assess and analyze pars interarticularis confidently than conventionally utilized MRI sequences in patients being evaluated for axial back pain.

Measurement Analysis of Ice Ball Size during CT-Guided Cryoablation Procedures for Better Prediction of Final Ice Ball Size and Avoidance of Complications

Introduction Cryoablation is the destruction of living tissue by the application of extreme freezing temperature. There has been an increase in the use of cryoablation in the management of musculoskeletal lesions, in particular fibromatosis.

Aim This study aimed to measure the average and relative increase in size of the cryoablation ice ball after the first (10 minutes) and second freeze cycles (20 minutes) to accurately predict the size of the ice ball between first and second freezes to help prevent any unwanted damage of the nearby skin and neurovascular structures. This is especially important when ablating in relatively small body parts such as in the appendicular skeleton.

Material and Methods Eight patients treated with cryoablation over a 12-month period for fibromatosis were, included in the study. The size and volume of the ice ball were measured during the first and second cycle of cryoablation.

Results The average patient age of the cohort was 35.6 years old (min 28 and max 43). There was female predominance in the study (3:2, F:M). There was a significant increase (26%) in the linear dimensions and almost doubling in the volume of the ice ball between freeze cycles (p-value = 0.0037 for dimensions and p-value = 0.0002 for volumes).

Conclusion This pilot study is a preliminary attempt to predict the eventual size of the ice ball during cryoablation procedures when treating cases of fibromatosis. This should help in planning cryoablation to ensure decrease morbidity by preventing injury to adjacent critical structures (neurovascular bundle and skin).

Alteration in the Cross-sectional Area (CSA) Ratio of the Paraspinal Muscles following Vertebral Insufficiency Fractures

Background  Vertebral insufficiency fractures in the elderly are associated with increased morbidity and mortality. Early diagnosis is essential to direct patient-specific rehabilitation. Aims  We hypothesize that in patients with vertebral insufficiency fractures, there is atrophy of the psoas and paraspinal muscles with alteration in the cross-sectional area (CSA) of the muscles. Materials and Methods  Magnetic resonance imaging (MRI) studies for 100 consecutive patients, older than 60 years presenting with lower back pain, were included in the study. For each MRI study, the CSA of the psoas and paraspinal muscles (multifidus) at the level of L4/5-disc space was measured to calculate the cross-sectional area ratio (CSAR) by two readers. One reader repeated the measurements after an interval of 2 weeks. We divided the patients ( n  = 100) into various groups based on the number of vertebral fractures. Results  In total, 77 patients with vertebral body fractures (48 with one, 16 with two and 13 with more than two fractures) were identified with a mean age of 73 (range 60-92) years. The ratio of multifidus CSA to psoas CSA was calculated with mean values of each group (1-4) as 2.56, 1.89, 2.09 and 2.16, respectively. There was statistically significance difference of the CSAR between the cohorts ( p -value = 0.0115). Conclusion  Vertebral insufficiency fractures in the elderly are associated not only with atrophy of psoas and the multifidus group of muscles as evident by the CSA values, but they also affect the CSAR depending on the number of fractures. This finding may help to direct targeted patient-specific physiotherapy rehabilitation and interventions to prevent further such fractures.

Optimisation of imaging parameters during CT guided interventional procedures in patients with total hip arthroplasty

Objective

To determine the optimal KV and mAs settings during CT guided injections in the presence of a total hip arthroplasty so that image quality is maintained whist keeping the dose as low as reasonably achievable.

Methods

A total hip arthroplasty phantom with needles with differing gauges was scanned using different CT parameters (from low dose to high dose) and evaluating if this had any effect on needle conspicuity. Conspicuity was graded from 1 to 3 by 2 independent blinded reviewers.

Results

Irrespective of the CT settings used (high dose or low dose parameters) needle conspicuity was not adversely affected by the THA for either scorer, therefore a kVp of 100 mA and a. In addition the needle gauge did not affect the conspicuity of the needle.

Conclusion

CT guided injections in this total hip arthroplasty phantom model can be performed without any adverse effect on the conspicuity of the needle tip on low dose CT settings.

Advancement in knowledge

This paper enables one to optimise the kV and mA while performing interventional procedures.

609 Metachronous Osteoid Osteoma of the Mid-Diaphysis of the Fibula and Distal Humerus: A Case Report

A 7-year-old boy presented with a 4-week history of pain and swelling of the right leg. He had a history of mucoepidermoid carcinoma of the parotid gland, treated by surgical resection without any complication. There was no other significant past medical history. A radiograph of the right leg showed a lytic lesion of the right diaphysis of the fibula with periosteal reaction. An MRI of the right leg showed osteoid osteoma of the fibula with marked cortical thickening with osseous and soft tissue oedema. The patient subsequently had a Jamshidi biopsy and curettage of the lesion, with the histopathological results of the biopsy showing fragments of a typical osteoid osteoma nidus with irregular calcified bony lamellae. His symptoms had significantly improved after the procedure, and he was ambulating without any discomfort or pain. The patient remained asymptomatic until he returned seven years later with right elbow swelling, pain and reduced range of movement over 2–3 months. A radiograph of the elbow joint had shown a large effusion with a sclerotic lesion on the coronoid fossa of the distal humerus in keeping with an osteoid osteoma. The patient had a confirmational biopsy and subsequently radiofrequency ablation of the lesion with complete resolution of pain. To our knowledge, our case is an atypical presentation of osteoid osteoma in two widely separate bones, between the lower and the upper limb separated by seven years disease-free interval.

The influence of site on the incidence and diagnosis of solitary central cartilage tumours of the femur. A 21st century perspective

OBJECTIVE

To determine the incidence of central cartilage tumours (CCTs) in the femur and the impact of site (proximal, mid and distal thirds) on tumour grade. To compare study results with historically published data.

MATERIALS AND METHODS

Retrospective review of solitary CCTs arising in the femur over the past 13 years. Data collected included location (proximal, mid and distal thirds) and final diagnosis in terms of tumour grade based on imaging features ± histology. Case material collected from three bone tumour textbooks provided historical data.

RESULTS

430 solitary CCTs were included in the femur. 73% cases arose in the distal, 3.7% in the mid and 23% in the proximal femur. The ratio of "benign" (combining enchondroma and atypical cartilaginous tumour (ACT)) to higher grade chondrosarcoma (CS) was 11:1 in the distal, 1:1 in the mid and 1:1.5 in the proximal femur, the distribution of benign to malignant tumours being significantly different between the regions (F test, p < 0.05). Comparison with historical data showed a reversal of the benign (enchondroma) to malignant (ACT and higher grade CS) of 30%:70%-84%:16% in the current series.

CONCLUSIONS

The site of origin of a CCT in the femur has an impact on final diagnosis with CS uncommon in the distal as compared with the mid and proximal femur. This is in contradistinction to historical data where the incidence of CS exceeded that of enchondroma at all sites.

Metachronous Osteoid Osteoma of the Mid-Diaphysis of the Fibula and Distal Humerus: A Case Report

Osteoid osteomas are mostly solitary. We report a case of metachronous osteoid osteoma of mid-diaphysis of fibula followed by distal humeral osteoid osteoma after a 7-year interval.

Can Non-Contrast 3T MRI scans predict the type of labral procedure in hip arthroscopy?

PURPOSE

The study proposed a simple classification system that aimed at predicting the labral procedure during hip arthroscopy using images from unenhanced 3T MRI scans.

PATENTS AND METHODS

Forty patients undergoing hip arthroscopy had their MRI scans reviewed pre-operatively by one of two senior radiologists and classified into: type 1: stable labrum with intra-substance degeneration (no labral repair required), type 2: unstable labrum, no intra-substance degeneration (labral repair required), or type 3: unstable labrum with intra-substance degeneration (Labral repair not feasible). Hip arthroscopy is carried out by one of two surgeons and classified accordingly while blinded to the radiologists' assessment.

RESULTS

The pre-operative radiological classification managed to predict the labral procedure in 29 cases out of 40 (72.5%). The gamma value was 0.83, and the kappa value was 0.46 denoting moderate agreement. The inter-class correlation coefficient was 0.52 indicating moderate reliability.

CONCLUSION

The proposed classification showed a moderate agreement between the radiological findings and arthroscopic findings. As we cannot accurately correlate the MRI findings with the type of surgical management, the surgeon should be prepared for all scenarios of labral procedures.

LEVEL OF EVIDENCE

Level IV (case series).

The Linear Hallux Valgus Offset- A novel way to measure Hallux Valgus

INTRODUCTION

Hallux Valgus (HV) is a complex deformity involving the first ray of the forefoot and a common cause of forefoot pain. Several radiological measurements such as Hallux Valgus Angle (HVA), First Metatarsophalangeal Angle (IMA) and Distal metatarsal articular angle (DMAA) exist to calculate the severity of HV and direct patient management. However, these are angular measurements are prone to error with variable intra- and inter-observer reliability.

PURPOSE

To describe a new radiological linear hallux valgus offset (LHVO) to measure HV deformity.

PATIENT AND METHODS

We performed a retrospective cohort study looking at Antero-posterior, weight-bearing foot radiographs of 100 consecutive patients with forefoot pain referred to our foot and ankle clinic. Demographic details, clinical indication, HVA (hallux valgus angle) and LHVO were measured for each patient and data were analyzed using the student t-test. Intraclass Correlation Coefficient (ICC) analysis was evaluated to assess the intra-class reliability between observers.

RESULTS

There was a female predominance of approximately 2:1, with 51.3 years (range 13-86 years). There was a statistically significant difference of LHVO between normal and hallux valgus cohorts with a p-value of 0.0001. The LHVO gave moderate intra-observer and inter-observer reliability on ICC analysis of 0.7.

CONCLUSION

The LHVO can be an additional measure of assessing severity of hallux valgus. In contrary to the traditional angular measurements, this linear measure is easier to calculate and reproducible on plain, weight bearing radiographs. LHVO measurement has shown a moderate inter-observer reliability in the study to complement traditional radiological evaluation of hallux valgus alignment.

Isolated pathologies of Tensor Fasciae Latae: Retrospective cohort analysis from a tertiary referral centre

INTRODUCTION

Tensor Fasciae Latae (TFL) and the iliotibial band (ITB) act as a single functional unit in maintaining pelvic stability whilst standing, walking, or running in human beings. The Tensor Fasciae Latae (TFL) muscle acts across the hip and the knee joint. Consequently, though its pathologies traditionally present with lateral hip pain, identifying the precise clinical diagnosis can be a challenge.

PATIENTS AND METHODS

A retrospective search for the keyword 'Tensor Fasciae Latae'/iliotibial band (ITB) was performed of our Radiology Information System (RIS) and Picture Archiving and Communication System (PACS), Computerised Radiology Information System (CRIS) at our tertiary orthopaedic referral centre of a for orthopaedic oncology over a period of 13 years (2007-2020). Data was collected from RIS, oncology database and local histopathology laboratory records. Patient demographics, clinical characteristics, complementary imaging and clinical management outcome were documented.

RESULTS

We identified 35 patients with a mean age of 66 years (range 19-94 years). There were 18 female and 17 male patients. Lateral hip lump and pain were the most frequent clinical finding/presentation features. A variety of pathologies such as benign and malignant tumours, including vascular and tumour mimic lesions involving the TFL muscle were identified. Atrophy and pseudohypertrophy of TFL was the commonest pathology found; accounting for two thirds of the cases.

CONCLUSION

Tensor Fasciae Latae (TFL) can be afflicted with a broad spectrum of pathologies. Radiological imaging especially cross-sectional imaging modality is crucial in guiding appropriate patient management of TFL conditions. Our analysis suggests isolated TFL lesion are more likely to be benign conditions, presenting commonly as hip pain and swelling.

Isolated Complete Distal Biceps Femoris Tendon Tears: Case Series and Literature Review

The Biceps femoris is a vital component of the posterolateral corner of the knee. We report two cases of isolated rupture of the biceps femoris, discuss the possible mechanism of injury, and review the literature.

Spontaneous Isolated Iliopsoas Tendon Tear in Elderly-Case Report and Review of Literature

Iliopsoas tendon tears are rare. These typically occur in young and can be associated with avulsion fractures of lesser trochanter. We report a case of full thickness rupture of iliopsoas tendon in 87-year-old male without avulsion of the lesser trochanter.

A Rare Presentation of Osteoid Osteoma in a 77-Year-Old Patient, Treated with Computer Tomography-Guided Percutaneous Radiofrequency Ablation

Osteoid osteoma (OO) is a benign bone forming tumor characterized by small size and a disproportionate amount of pain. They are most commonly seen between the ages of 5 and 30 years; however, they can be seen in the older patient albeit infrequently. The hands and feet are the least common site of OO among the extremity bones. We present a case of an OO in the hand of a 77-year-old man who underwent successful treatment with computed tomography–guided percutaneous radiofrequency ablation. We believe this is the oldest recorded patient in the medical literature with a histologically confirmed OO. The condition should therefore be considered in the differential diagnosis of a painful sclerotic bone lesion in this age group to avoid a delay in diagnosis and subsequent treatment.

Prevalence of Enchondromas of the Proximal Femur in Adults as an Incidental Finding on MRI of the Pelvis

Objective  To determine the prevalence of enchondroma in adults as an incidental finding in the proximal femur on magnetic resonance imaging (MRI). Materials and Methods  A retrospective review of the MRI scans of the pelvis in a series of adult patients was conducted. All presented with nononcological musculoskeletal complaints. The site, size, and appearances of the enchondromas were identified according to criteria from previous studies. Results  A total of 1,209 proximal femora in 610 patients were reviewed and a total of 9 enchondromas were identified. These ranged from 0.6 to 2.5 cm in length (mean 1.3 cm). None showed aggressive features suggestive of malignancy. Three cases (33%) underwent follow-up MRI scans which showed no change in size or morphology. Conclusion  The prevalence on MRI of incidental enchondromas arising in the proximal femur is 0.7%. This is three to four times less common than seen in the proximal humerus and around the knee.

Vasovagal reactions in ultrasound guided musculoskeletal injections: A study of 2,462 procedures

OBJECTIVE

to determine the rate of the vasovagal reaction (VVR) in ultrasound guided musculoskeletal injections (USGIs) and to investigate effect of injection site, age, and gender on this rate.

MATERIAL AND METHODS

Retrospective analysis of all USGIs performed from the 1st of January 2019 to the 31st of December 2019 in single tertiary orthopaedic hospital. Two thousand four hundred and sixty two consecutive subjects undergoing USGIs were included. Statistical analysis used to determine the rate of the overall VVR in USGIs and to determine if site of the injection or joint injected has an effect on this rate as well as age and gender effect.

RESULTS

Overall rate of VVR was 2.3% with shoulder and small joints of the hands and feet are more commonly affected than other sites. Females and patients aged younger than 65 years may be subjected to higher rate of VVR.

CONCLUSIONS

VVR has an overall low occurrence in USGI. The higher rate of VVR for shoulder and small joints of hands and feet procedures. Care should be taken when positioning a patient prior to the procedure to allow for a VVR in case it happens. VVR are more likely to occur in females and less likely in age more than 65 years.

Global perspective of familial hypercholesterolaemia: a cross-sectional study from the EAS Familial Hypercholesterolaemia Studies Collaboration (FHSC)

BACKGROUND

The European Atherosclerosis Society Familial Hypercholesterolaemia Studies Collaboration (FHSC) global registry provides a platform for the global surveillance of familial hypercholesterolaemia through harmonisation and pooling of multinational data. In this study, we aimed to characterise the adult population with heterozygous familial hypercholesterolaemia and described how it is detected and managed globally.

METHODS

Using FHSC global registry data, we did a cross-sectional assessment of adults (aged 18 years or older) with a clinical or genetic diagnosis of probable or definite heterozygous familial hypercholesterolaemia at the time they were entered into the registries. Data were assessed overall and by WHO regions, sex, and index versus non-index cases.

FINDINGS

Of the 61 612 individuals in the registry, 42 167 adults (21 999 [53·6%] women) from 56 countries were included in the study. Of these, 31 798 (75·4%) were diagnosed with the Dutch Lipid Clinic Network criteria, and 35 490 (84·2%) were from the WHO region of Europe. Median age of participants at entry in the registry was 46·2 years (IQR 34·3-58·0); median age at diagnosis of familial hypercholesterolaemia was 44·4 years (32·5-56·5), with 40·2% of participants younger than 40 years when diagnosed. Prevalence of cardiovascular risk factors increased progressively with age and varied by WHO region. Prevalence of coronary disease was 17·4% (2·1% for stroke and 5·2% for peripheral artery disease), increasing with concentrations of untreated LDL cholesterol, and was about two times lower in women than in men. Among patients receiving lipid-lowering medications, 16 803 (81·1%) were receiving statins and 3691 (21·2%) were on combination therapy, with greater use of more potent lipid-lowering medication in men than in women. Median LDL cholesterol was 5·43 mmol/L (IQR 4·32-6·72) among patients not taking lipid-lowering medications and 4·23 mmol/L (3·20-5·66) among those taking them. Among patients taking lipid-lowering medications, 2·7% had LDL cholesterol lower than 1·8 mmol/L; the use of combination therapy, particularly with three drugs and with proprotein convertase subtilisin-kexin type 9 inhibitors, was associated with a higher proportion and greater odds of having LDL cholesterol lower than 1·8 mmol/L. Compared with index cases, patients who were non-index cases were younger, with lower LDL cholesterol and lower prevalence of cardiovascular risk factors and cardiovascular diseases (all p<0·001).

INTERPRETATION

Familial hypercholesterolaemia is diagnosed late. Guideline-recommended LDL cholesterol concentrations are infrequently achieved with single-drug therapy. Cardiovascular risk factors and presence of coronary disease were lower among non-index cases, who were diagnosed earlier. Earlier detection and greater use of combination therapies are required to reduce the global burden of familial hypercholesterolaemia.

FUNDING

Pfizer, Amgen, Merck Sharp & Dohme, Sanofi-Aventis, Daiichi Sankyo, and Regeneron.

The Haleem-Marks-Botchu classification: a novel CT-based classification for intracanal rib head penetration

PURPOSE

Intracanal rib head penetration is a well-known entity in dystrophic scoliotic curves in neurofibromatosis type 1. There is potential for spinal cord injury if this is not recognised and managed appropriately. No current CT-based classification system is currently in use to quantify rib head penetration. This article aims to propose and evaluate a novel CT-based classification for rib head penetration primarily for neurofibromatosis but which can also be utilised in other conditions of rib head penetration.

MATERIALS AND METHODS

The grading was developed as four grades: normal rib head (RH) position-Grade 0, subluxed extracanal RH position-Grade 1, RH at pedicle-Grade 2, intracanal RH-Grade 3. Grade 3 was further classified depending on the head position in the canal divided into thirds. Rib head penetration into proximal third (from ipsilateral side)-Grade 3A, into the middle third-Grade 3B and into the distal third-Grade 3C. Seventy-five axial CT images of Neurofibromatosis Type 1 patients in the paediatric age group were reviewed by a radiologist and a spinal surgeon independently to assess interobserver and intraobserver agreement of the novel CT classification. Agreement analysis was performed using the weighted Kappa statistic.

RESULTS

There was substantial interobserver correlation with mean Kappa score (k = 0.8, 95% CI 0.7-0.9) and near perfect intraobserver Kappa of 1.0 (95% CI 0.9-1.0) and 0.9 (95% CI 0.9-1.0) for the two readers.

CONCLUSION

The novel CT-based classification quantifies rib head penetration which aids in management planning.

Diagnostic accuracy of ultrasound and magnetic resonance imaging in detecting Stener lesions of the thumb: systematic review and meta-analysis

This study assesses the diagnostic accuracy of ultrasound and magnetic resonance imaging (MRI) in diagnosing Stener lesions of the thumb. MEDLINE, PubMed, Embase and Cochrane CENTRAL were searched for studies using ultrasound or MRI to detect Stener lesions following suspected thumb ulnar collateral ligament injuries. The reference standard was surgical exploration or clinical joint stability. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. A random-effects bivariate meta-analysis was used to estimate pooled sensitivity and specificity. Forest plots were generated. Nine ultrasound (315 thumbs) and six MRI (107 thumbs) studies were included in meta-analysis (all high risk of bias). Pooled sensitivity and specificity for ultrasound were 95% and 94%, and for MRI were 93% and 98%. Both ultrasound and MRI demonstrate high diagnostic accuracy in detecting Stener lesions. Ultrasound is an appropriate first-line imaging modality.

A radiological diagnostic approach to tumours and tumour-like lesions of the calcaneus

OBJECTIVE

The calcaneus is a rare location for the development of primary bone tumours. The purpose of the study is to review the imaging findings in a cohort of patients presenting with tumours and tumour-like lesions of the calcaneus and to develop a more structured approach to the diagnosis of calcaneal lesions.

METHODS

A retrospective study with a collection of 167 cases of calcaneal tumours and tumour-like lesions from our tertiary orthopaedic oncology institution over a period of 13 years. Cases were reviewed by two consultant musculoskeletal radiologists and the location of the lesion within the calcaneus and demographics of the patient were noted for each case. A diagnostic algorithm, which is based on patient age and tumour location, was then extrapolated.

RESULTS

Out of the 167 cases, we identified 24 different calcaneal pathologies which included both tumours and tumour-like lesions. The most common being simple bone cysts (18.3% of cases) and intra-osseous lipoma (15% of cases) sited in the diaphyseal equivalent of the calcaneus. A diagnostic algorithm was formulated, which describes the most common location of the different pathologies including both benign and malignant pathologies, subdivided by age.

CONCLUSION

Our algorithm should help the radiologist narrow down the differential diagnosis when evaluating calcaneal lesions.

ADVANCES IN KNOWLEDGE

This article provides a radiological approach to calcaneal lesions.

Birmingham Intervention Tent Technique (BITT): A Technical Note

Objective We describe a novel and safe CT biopsy technique that we have termed the “Birmingham intervention tent technique (BITT).” This technique is ideal for biopsying osseous lesions where a direct approach is not possible due to difficult positioning.

Methods The BITT uses a plastic surgical forceps clamp attached at an angle to the biopsy needle, creating a tent shape. The finger rings of the forceps is stabilized on the table.

Results In our institution, we have already used the BITT successfully in over 10 cases.

Conclusion The BITT is an inexpensive and reproducible technique.

Iyengar-Botchu (IB) confluence of the medial knee- anatomy and clinico-radiological review

The Iyengar-Botchu confluence is a quadrilateral space on the medial side of the knee. Due to the presence of unique anatomical structures, this region is prone to injuries. The aim of this pictorial review is to illustrate an anatomical description of the structures, which form the IB complex confluence. Clinico-pathological correlation of common conditions associated with these structures will increase awareness of injuries in this area. A complementary imaging guidance will support clinical diagnosis and appropriate patient management.

Myositis ossificans revisited - The largest reported case series

INTRODUCTION

Myositis ossificans (MO) is a condition characterised by the formation of non-neoplastic heterotropic ossification in extraskeletal soft tissues.

MATERIAL AND METHODS

We performed a retrospective study of our radiology databases within our tertiary orthopaedic centre to identify all cases of MO, reported on X ray, Magnetic resonance imaging (MRI) and Computed tomography (CT) over the past 13 years (2007-2020).

RESULTS

We identified 68 cases of MO, which were included into our cohort. The average age of our patients was 36 years (range 4-84 years). 73% of cases (n = 50) were found to affect the lower limb muscles with the majority in the quadriceps.

CONCLUSION

We report the largest case series of MO and discuss the demographics, diagnoses and management.

COVID-19 pandemic and medical education

COVID-19 has had significant impact on medical students and medical education. In this article, we discuss the effect on medical education and general well-being based on survey and measures to mitigate the same.

Imaging review of normal anatomy and pathological conditions involving the popliteus

Popliteus is an integral component of the posterolateral corner of the knee. We review the anatomy and various pathologies affecting the popliteus.

Spinal collision lesions

Collision lesions are rare neoplasms often described in the hepatobiliary system, genitourinary system and adrenal glands. Vertebral haemangiomas (VH) are the most common lesions involving the vertebral bodies. VHs are usually asymptomatic and considered as "Do not touch" lesions. Rarely they can be symptomatic. Imaging findings of typical and atypical haemangiomas, variant forms of haemangioma such as aggressive haemangiomas are well known. Collision lesions involving VHs are extremely rare. This article presents a series of cases with collision lesions of the vertebral body involving VHs.

ADVANCES IN KNOWLEDGE

This Case series demonstrates the various collision lesions in spinal haemangioma.

Can MRI be used as a safe and expedient option for calculating Spinal Instability Neoplastic Score for patients with metastatic spinal cord compression?

AIMS

The aim of this study was to assess the reliability of using MRI scans to calculate the Spinal Instability Neoplastic Score (SINS) in patients with metastatic spinal cord compression (MSCC).

METHODS

A total of 100 patients were retrospectively included in the study. The SINS score was calculated from each patient's MRI and CT scans by two consultant musculoskeletal radiologists (reviewers 1 and 2) and one consultant spinal surgeon (reviewer 3). In order to avoid potential bias in the assessment, MRI scans were reviewed first. Bland-Altman analysis was used to identify the limits of agreement between the SINS scores from the MRI and CT scans for the three reviewers.

RESULTS

The limit of agreement between the SINS score from the MRI and CT scans for the reviewers was -0.11 for reviewer 1 (95% CI 0.82 to -1.04), -0.12 for reviewer 2 (95% CI 1.24 to -1.48), and -0.37 for reviewer 3 (95% CI 2.35 to -3.09). The use of MRI tended to increase the score when compared with that using the CT scan. No patient having their score calculated from MRI scans would have been classified as stable rather than intermediate or unstable when calculated from CT scans, potentially leading to suboptimal care.

CONCLUSION

We found that MRI scans can be used to calculate the SINS score reliably, compared with the score from CT scans. The main difference between the scores derived from MRI and CT was in defining the type of bony lesion. This could be made easier by knowing the site of the primary tumour when calculating the score, or by using inverted T1-volumetric interpolated breath-hold examination MRI to assess the bone more reliably, similar to using CT. Cite this article: Bone Joint J 2021;103-B(5):971-975.

Iliotibial band enthesopathy: an unusual cause of lateral knee pain post total knee replacement

Iliotibial band (ITB) pathology is one of the main causes of lateral knee pain. The enthesopathy of the ITB at its insertion post total knee replacement (TKR) is a rare cause of lateral knee pain. We describe a series of cases of ITB enthesopathy with sonographic findings and management.

Lesions of the heel fat pad

OBJECTIVE

The heel fat pad (HFP) is a specialized soft tissue structure formed of adipose tissue that overlies the inferior and posterior aspect of the calcaneus and provides the cushioning effect of the heel. Lesions of the HFP are rare and can be a cause of debilitating heel pain that may often pose a challenge to clinicians. This study provides a series of lesions identified within the HFP.

METHODS AND MATERIALS

A retrospective review of heel pad lesions over a 12 year period was conducted at our tertiary orthopaedic oncology centre. All lesions of the heel fat pad were included in the study. Plantar fasciitis was excluded.

RESULTS

There were 17 heel pad lesions identified, of which the majority (n = 15) were benign.

CONCLUSION

We highlight a wide spectrum of pathologies that can occur in the HFP. Although rare, clinicians should be aware of these lesions, to initiate appropriate management.

Tumours of the odontoid peg revisited

Introduction

Tumours of the odontoid peg are rare but can potentially cause significant morbidity and mortality.

Methods

A retrospective review of oncology and radiology database of tertiary orthopaedic oncology centre for all lesions affecting the odontoid peg over the last 12 years was performed.

Results

We identified a total of 15 tumours involving the odontoid peg, majority being malignant. Myeloma was the most common tumour.

Conclusion

Tumours of the odontoid peg are rare. Spinal surgeons and Radiologists need to be aware of them.

Impact of the COVID-19 pandemic on radiologists

COVID-19 pandemic is one of the biggest crises faced by health-care systems in the recent times. The aim of this study was to assess the impact of the COVID-19 pandemic on radiology workflow, working pattern, training and continuing professional development (CPD) activities, as well as personal well-being of the radiologists during the pandemic. Material and Methods: Questionnaire designed to gather the opinions regarding the impact of the COVID-19 pandemic was distributed to radiologists throughout the world in electronic format. Anonymized responses were obtained and analyzed. Two hundred radiologists, working in 17 different countries, responded to our questionnaire. Majority of the respondents were from India (72.8%) and 70% of the them were in the age group of 25–45 years. About 80% of respondents felt that they were well protected or moderately well protected in terms of the personal protective equipment (PPE), however, most of them felt that the use of PPE had affected their ability to work. Similar number of radiologists felt that there was significant reduction in the radiology workload. More than half of the respondents felt that their working patterns were altered by the pandemic with drastic impact on teaching, CPD activities, and personal well-being. COVID-19 pandemic has had profound impact on the radiologists all over the world. Learning from the experiences of the first wave should be used to provide innovative solutions to some of the challenges posed to provide better radiology services, training, and improve the well-being of radiologists if we encounter a similar situation in the future. COVID-19 pandemic had significant impact on radiologists. Radiologists felt that they were well or moderately well protected with PPEs; however, PPEs affected their ability to work. Radiology workflow was significantly reduced in the pandemic with more radiologists working from home. COVID-19 pandemic had deleterious effect on radiologist’s well-being, education, and CPD activities.

Exploring the correlation between increased femoral anteversion and pars interarticularis defects in the lumbar spine: A single center experience

Introduction

Altered femoral version can result in lumbar hyperlordosis and hip spine syndrome. We conducted a retrosepctive study to evalute if there is correlation between altered femoral version and pars defect.

Materal and Methods

A cohort of pateints with CT rotational profile and MR of lumbar spine over a 12 year period were included in the sutdy. The femoral version was calculated and the MR was evaluated for pars defect.

Results

130 patients had CT rotational profile and MR of lumbar spine with a female predomiannce (94 female and 36 males) and average age of 24.3 years. There were 6 patients with bilateral pars defects involving L5 (3 with increased femoral version, 2 with decreased version and one had normal version).

Conclusion

Increased femoral anterversion is not associated with increased prevalence of pars defects.

The Haleem-Botchu classification: a novel CT-based classification for lumbar foraminal stenosis

PURPOSE

No clinical CT-based classification system is currently in use for lumbar foraminal stenosis. MRI scanners are not easily available, are expensive and may be contraindicated in an increasing number of patients. This study aimed to propose and evaluate the reproducibility of a novel CT-based classification for lumbar foraminal stenosis.

MATERIALS AND METHODS

The grading was developed as four grades: normal foramen-Grade 0, anteroposterior (AP)/superoinferior (SI) (single plane) fat compression-Grade 1, both AP/SI compression (two planes) without distortion of nerve root-Grade 2 and Grade 2 with distortion of nerve root-Grade 3. A total of 800 lumbar foramen of a cohort of 100 random patients over the age of 60 who had undergone both CT and MRI scans were reviewed by two radiologists independently to assess agreement of the novel CT classification against the MRI-based grading system of Lee et al. Interobserver(n = 400) and intraobserver agreement(n = 160) was also evaluated. Agreement analysis was performed using the weighted kappa statistic.

RESULTS

A total of 100 patients (M:F = 45:55) with a mean age of 68.5 years (range 60-83 years were included in the study. The duration between CT and MRI scans was 98 days (range 0-540, SD-108). There was good correlation between CT and MRI with kappa scores (k = 0.81) and intraobserver kappa of 0.89 and 0.98 for the two readers.

CONCLUSION

The novel CT-based classification correlates well with the MRI grading system and can safely and accurately replace it where required.

Imaging of the lesions in the lateral muscle compartment of the forearm, alias mobile wad of Henry: Demographics, radiological anatomy and surgical relevance

INTRODUCTION

Mobile wad of Henry (MOH) is a preferred surgical term used to describe the lateral compartment muscles of the forearm consisting of brachioradialis, extensor carpi radialis longus and brevis. The lesions in this compartment are uncommon. In this paper, we describe the largest series of the MOH lesions including their demographics, imaging appearances and importance of surgical anatomy whilst managing MOH lesions via radiological or surgical interventions.

METHODS

A retrospective search of oncology database for lesions in MOH at our tertiary orthopaedic oncology institute was performed for the last 12 years (2007-2019) after obtaining institutional review board approval. We further analyse data to obtain further clarity of various neoplasms occurring at this particular anatomical site.

RESULTS

We identified 28 patients with MOH lesions with an age range of 8 to 84 years and a male predominance. Imaging-wise, majority of lesions were benign following characteristics of lipomatous tumours, lipomas being the commonest. Other relatively uncommon benign lesions were nodular fasciitis, myositis ossificans and brachioradialis muscle injury; whereas aggressive MOH soft tissue neoplasms included synovial sarcoma and fibrohistiocytoma.

CONCLUSION

Although majority of MOH lesions are benign, one needs to be aware of spectrum containing uncommon benign and aggressive MOH lesions. When posed with dilemma, the MOH lesions require multidisciplinary approach with close collaboration of the radiologist, the surgeon and the pathologist to decide further management.

Hamstring origin-anatomy, angle of origin and its possible clinical implications

INTRODUCTION

The posterior compartment of the thigh is composed of three major muscles collectively known as the hamstring muscles. These consist of the biceps femoris short and long head, semimembranosus and semitendinosus. Excluding the short head of biceps femoris, the hamstrings contribute to the movement of the hip and the knee joints as they span across both joints. Our hypothesis is that the nature of the conjoint tendon -ischial angle predisposes to an increased risk of tearing in this hamstring component. We therefore aim to look at the anatomy of the hamstring origin at the ischial tuberosity and spatial relationship between the long head of biceps, semitendinosus and semimembranosus in the form of vector angles.

MATERIAL AND METHODS

100 consecutive pelvic MRIs in patients under the age of 40 years were reviewed by musculoskeletal radiology fellow and a consultant musculoskeletal radiologist with more than 10 years' experience in musculoskeletal radiology and measured the angle of origin of conjoined tendon and semimembranosus at its ischial origin. P value using a paired t-test was less than 0.0001 confirming that the difference in the vector angle of the different hamstring components was statistically significant.

RESULTS

The median angle of origin of conjoined tendon was 12° and for semimembranosus was 6°. Applying the concept of Newton's second law to the angles calculated we demonstrated that an increase of 9% force applied to the conjoint tendon origin when compared to the semimembranosus tendon.

CONCLUSION

We hypothesis that the difference in the angle of origin of the components of hamstrings might be one of the reasons for the difference in the incidence and patterns of the injuries of the various muscles of the hamstrings.

MRI assessment of anatomy and pathology of the iliofemoral ligament

The iliofemoral ligament is strongest ligament of the body. We review the magnetic resonance imaging (MRI) appearances of the iliofemoral ligament, and discuss the disease entities that may affect this region.

Standard operating procedure of image-guided intervention during the COVID-19 pandemic: a combined tertiary musculoskeletal oncology centre experience

AIM

To evaluate the response measures in continuing an image-guided intervention service in two tertiary-level musculoskeletal oncology centres during the COVID-19 pandemic.

MATERIALS AND METHODS

This study was a retrospective review of all patients undergoing image-guided intervention in the computed tomography (CT) and normal ultrasound (US) rooms from 24 March 2020 to 24 May 2020 (during the COVID-19 pandemic peak) at Royal National Orthopaedic Hospital, London, and Royal Orthopaedic Hospital, Birmingham, UK. Measures were put in place to address air pressures, airflow direction, aerosol generation, and the safe utilisation of existing scanning rooms and work lists for interventional procedures.

RESULTS

Three hundred and thirty-one patients (164 at Royal National Orthopaedic Hospital and 167 at Royal Orthopaedic Hospital) underwent image-guided procedures at both sites in the CT and US rooms. At the Royal National Orthopaedic Hospital, 40% of all procedures were performed under general anaesthesia. These consisted of 47 CT biopsies, 7 CT radiofrequency ablations (RFAs), and 12 US biopsies. At the Royal Orthopaedic Hospital, 86% of all procedures were performed under local anaesthetic, with no general anaesthetic procedures. These consisted of 61 CT biopsies and 83 US biopsies. All 256 patients having procedures in the CT room had no post-procedural complications or COVID-19-related symptoms and morbidity on follow-up.

CONCLUSION

By adopting a pragmatic approach with meticulous planning, a limited, but fully functional image-guided interventional list can be run without any adverse patient outcomes.

•

COVID-19 has had a significant impact on CT interventional procedures.

•

Air pressures and appropriate ventilation systems need to be considered.

•

A pragmatic and meticulous approach is crucial in operating a functional service.

Power Doppler in musculoskeletal ultrasound: uses, pitfalls and principles to overcome its shortcomings

Power Doppler (PD) is used widely in musculoskeletal ultrasound, especially in the assessment of structures for evidence of inflammation and in evaluating soft tissue neoplasms. We reinforce and delineate the three cardinal principles of optimising PD assessment in order to avoid false positive or false negative results; namely (1) Optimal gain settings (2) Adequate transducer pressure, and (3) Proper patient/anatomical structure-of-interest positioning with complete tissue relaxation.

An imaging protocol for the management of central cartilage tumours of the proximal fibula

AIM

To retrospectively review a series of solitary central cartilage tumours (CCTs) of the proximal fibula and propose an imaging protocol for their management.

MATERIALS AND METHODS

Over 11 years, 48 patients were identified with a CCT of the proximal fibula. The initial magnetic resonance imaging (MRI) and follow-up imaging were assessed for tumour length, endosteal scalloping, or aggressive/malignant features. Each case was categorised according to the Birmingham Atypical Cartilage Tumour Imaging Protocol (BACTIP). The final diagnosis and outcome were reviewed to establish an appropriate imaging protocol for the management of similar cases in the future.

RESULTS

The final diagnosis based on imaging alone or imaging and histopathology was enchondroma in 46 cases (96%) and atypical cartilage tumour (ACT)/low-grade chondrosarcoma in two (4%). Using the BACTIP classification, the majority were type IC (48%) with type IA the second commonest (24%). Of 19 that underwent follow-up MRI, only two revealed any increase in length, neither of which was shown to be malignant. No cases re-presented later with evidence of malignant transformation.

CONCLUSION

There has been a significant increase in the number of CCTs of the proximal fibula referred to Royal Orthopaedic Hospital, Birmingham, over the past decade. This can largely be attributed to the increased use of MRI. The majority were benign with only 4% classified as an ACT. A modified BACTIP, the Fibular Atypical Cartilage Tumour Imaging Protocol (FACTIP) is presented, indicating which cases would benefit from follow-up imaging and which require referral to a specialist orthopaedic oncology service.

Ectopic breast tissue presenting as an enlarging abdominal mass

Ectopic breast tissue (EBT) is an uncommon entity that occurs in about 6% of the population, more frequently in Asian people. It manifests as a nonspecific soft tissue mass that can develop in any location along the "milk-line," with the axilla being the most frequently reported location. As with normal breast tissue, both benign and malignant processes can arise from EBT. Therefore, imaging plays an important role in the adequate assessment of these soft tissue lesions, characterizing its shape, borders, internal components, and vascularity, as well as its relationship with the deep fascia and adjacent structures. Here we present a case of a 33-year-old female Indian patient with an 8 cm soft tissue mass in the upper left abdominal quadrant with a recent increase in size. Clinical and imagiological evaluation were nonspecific but established the nonaggressive behavior of the lesion. To ultimately exclude malignancy, an ultrasound-guided biopsy was performed providing the histological diagnosis of EBT. This case report illustrates the value of clinical, radiological, and histological correlation in the approach of indeterminate soft-tissue tumors, with special focus on lesions in close proximity to the native breasts, where EBT should not be forgotten amongst differentials.

Anatomy and pathology of facet joint

Facet joints are the only synovial joints in the spine and can be involved in a large number of pathological processes including arthropathy, infection, inflammation, trauma and tumour. In this review article, we present a spectrum of pathologies that arise from or involve facet joints that we have encountered in our tertiary orthopaedic and spinal centre. The objective of this review is to create an aide memoire for the general radiologist who may encounter facet joint pathology, which they may not be familiar with.

Myositis ossificans of mobile wad of Henry-Tennis elbow mimic

Lateral epicondylitis also known as “tennis elbow” is the most common cause of lateral elbow pain. Several pathologies can mimic symptoms of tennis elbow. We present a case of myositis ossificans within the mobile wad of Henry (MWH), which presented with symptoms of tennis elbow and believe this to be the first reported case in literature.