and Thigh Ultrasound Disclosures: with MRI Correlation • Consultant: Bioclinica • Advisory Board: GE, Philips Jon A. Jacobson, M.D. • Book Royalties: Elsevier Professor of Radiology • Not relevant to this talk Director, Division of Musculoskeletal Radiology University of Michigan Note: all images from the textbook Fundamentals of Musculoskeletal Ultrasound are copyrighted by Elsevier Inc.

Hip: anterior recess Pathology: • Anterior and posterior layers • Joint abnormalities – Fibrous tissue + minute layer of synovium • Bursal pathology – Hyperechoic Radiology – Each 2 - 4 mm thick 1999; 210:499 • Muscle and tendon injury • Snapping hip syndrome • Miscellaneous pathology

Hip: anterior recess Hip Effusion: • Separation of anterior and posterior layers1 • Capsule distention at femoral neck > 7 mm or Anterior difference of 1 mm from opposite side2 Posterior Femur • Extension & abduction improves visualization3 • Do not internally rotate hip: capsule thickens

1Radiology 1999; 210:449 2Scand J 1989; 18:113 3Acta Radiologica 1997; 38:867

1 Hip Joint: septic effusion Hip Effusion: misconception • It is incorrect to assume that joint fluid may not be seen anterior due to gravity • Native hip: joint fluid distributes around * femoral neck • In no cases was fluid only seen posterior FH * Neck • Exception: after hip surgery * * Long Axis Moss et al. Radiology 1998; 208:43

Hip Joint: aseptic effusion Hip Joint: aseptic effusion

FH * Neck Acet FH * Neck Femoral Neck

Sagittal Axial

Hip Effusion: Pitfall: capsule thickening • Cannot predict • Internal rotation of hip: infection by ultrasound – Anterior hip capsule • Negative power color * – Thicker, convex anterior Doppler does not exclude infection* Head * • Guided aspiration Neck

External Rotation Internal Rotation * AJR 1998; 206:731

2 Pigmented Villonodular Juvenile Idiopathic Arthritis

Head Head

Erosion

Labral Tear and Paralabral Cyst Hip Labrum Chondrocalcinosis • Normal: – Hyperechoic, triangular • Degeneration: hypoechoic • Tear: – Anechoic cleft – Most common anterior Labral Tear – Possible paralabral cyst – Sensitivity 82%, specificity 60%* Acetab

Femoral Courtesy of D. Fessell, Ann Arbor, MI *Jin W et al. J Ultrasound Med 2012; 31:439 Head

CAM Impingement Femoroacetabular Impingement:

• Pincer-type: deep acetabulum • Cam-type – Broad irregular femoral neck – Possible cortical irregularity at US • Associated with anterior labrum tear • Consider dynamic evaluation Note: labral tear (yellow arrow) and Radiology 2005; 236:588 osseous bump (white arrow)

Courtesy of M. van Holsbeeck, Detroit, MI

3 Total Hip Hip Arthroplasty: Arthroplasty: • Ultrasound cannot differentiate small effusion • Metal components from post-op change1 demonstrate posterior • Suspect infection: reverberation A Acet Femur – Pseudocapsule > 3.2 mm: 2 • Artifact occurs deep to H Neck suspect infection prosthesis away from > 3.2 – Extra-articular fluid Head mm fluid collection (unlike collection MRI, CT) – Not visualized with Neck arthrography if non- communication 1Weybright PN et al. AJR 2003; 181:215 2AJR 1994; 163:381

Hip Arthroplasty: infection Hip Arthroplasty: infection

Superior Inferior

Femur

Native Coronal Radiograph Femur Teaching Point: Always screen soft tissues about an arthroplasty Sagittal prior to fluoroscopic joint aspiration

Metal-on-Metal Arthroplasty: pseudotumor Pathology: • Joint abnormalities

Troch • Bursal pathology Cup • Muscle and tendon injury

Neck Cup • Snapping hip syndrome • Miscellaneous pathology Anterior Lateral

4 Trochanteric Syndrome: • Most commonly caused by gluteus Trochanteric Bursal Fluid: minimus and medius tendon • Bursal fluid not normally seen abnormalities1 • Trochanteric : uncommon • Fluid distention: – 20% of symptomatic patients2 – simple fluid: anechoic – Not actually inflamed3 – complicated fluid: mixed echogenicity – Not associated with pain4 1Kong A et al. Eur Rad 2007; 17:1772 2Long SS et al. AJR 2013; 201:1083 3Sylva F et al. Clin Rheumatol 2008; 14:82 4Blankenbaker DG et al. Skeletal Radiol 2008; 37:903

Greater Trochanter Greater Trochanter

Yellow arrow = White arrow = Inferior 12 gluteus minimus

Axial MRI FACETS: AF = anterior; LF = lateral; SPF = superoposterior; PF = posterior 3 Superior 4 Pfirrmann et al. Radiology 2001; 221:469

Greater Trochanter Greater Trochanter Gluteus Medius Gluteus Minimus

Trochanteric TFL ITB Bursa ITB Gmed Gmin Glut Max

AF Subgluteus LF Minimus Bursa PF Gmax

Subgluteus AF: anterior facet Anterior Posterior Medius LF: lateral facet Bursa PF: posterior facet Yellow arrow = gluteus medius White arrow = gluteus minimus Note: ITB is formed by from and tensor fascia latae

5 Gluteus Minimus and Medius: Long Axis Gluteus Minimus: Long Axis

Gluteus Gluteus Medius Minimus

Gmed Gmed Gmed

AF

Anterior Anterior Facet Facet

From: Philippon et al. Orth J Sports Med 2014

Gluteus Medius: Long Axis Trochanteric Bursitis

Iliotibial Tract

LF

PF Lateral Facet

Transverse Coronal

Trochanteric Bursitis Bursa: • Hip joint communication in 10% – Increased with hip joint pathology • May extend cephalad into abdomen • May be mistaken for abscess: – Look for hip joint communication

Radiology 1995; 197:853

6 Iliopsoas Bursal Fluid Ischial or ischiogluteal Bursa • Uncommon • “Weaver’s Bottom” • Between ischial tuberosity and gluteus maximus

IP

Femoral Head Axial T1w post-gadolinium

Pathology: Gluteal Tendon Pathology: • Joint abnormalities • Tendinosis: hypoechoic, no defects • Bursal pathology • Partial tear: anechoic clefts • Complete tear: discontinuous tendon • Muscle and tendon injury • >2 mm cortical irregularity is associated with • Snapping hip syndrome tendon tear • Miscellaneous pathology – Positive predictive value = 90% (xray)*

*Steinert et al. Radiology 2010; 257:754

Gluteus Medius Tendinosis: Gluteus Medius

LF LF Short Axis Long Axis AF LF SPF

7 Tendinosis: Gluteus Minimus Tear: Gluteus Medius

AF LF AF AF LF LF

>2 mm cortical irregularity depth (x-ray) = 90% positive predictive value for gluteus tendon tear

Steinert et al. Radiology 2010; 257:754

Post-operative: Gluteus Medius Calcific Tendinosis: Gluteus Medius

AF LF LF AF LF SPF LF

Long Axis Short Axis

Semimembranosus: tendinosis Conjoined Tendons: tendinosis

Conjoint Conjoint Tendon Tendon

Ischium

Ischium SM

Long Axis Short Axis Conjoint Tendon Semimembranosus

Long Axis

8 Semimembranosus Tear Semimembranosus: remote tear

Conjoint Conjoint Tendon Tendon

ST ST

BF

SM

Sciatic Nerve Tear Normal Short Axis

Rectus Femoris: anatomy Aponeurosis Tear (Indirect Head): Rectus Femoris

Short Axis Long Axis Courtesy of Y. Morag, Ann Arbor, MI

Rectus Femoris Tear: full-thickness tear Calcific Tendinosis: rectus femoris

AIIS

Long Axis Abnormal Normal Long Axis

9 Direct Rectus Femoris Tear: full tear, pseudomass Calcific Tendinosis Head • Ultrasound-guided lavage and aspiration • 20 gauge spinal Long Axis needle

Short Axis Short Axis Axial T1w post-gado Before After

Rectus Femoris Tear: full tear, pseudomass Hematoma: adductors

Long Axis Axial Axial T2w

Seroma Thigh Splints: • Adductor insertion avulsion syndrome • Proximal - mid femur • Sports-related injuries • Stress fracture, edema

AJR 2001; 177:673 Sagittal

10 Adductor Insertion Avulsion Adductor Insertion Avulsion

Femur Femur

Coronal Plane Transverse

Morel-Lavallée Lesion Morel-Lavallée Lesion:

• Thigh and hip region Sub-Q Fat • Fluid collection: – Between subcutaneous fat and fascia – Closed de-gloving injury Muscle • Trauma Muscle Muscle

Mellado, AJR 2004; 182:1289 Coronal Transverse Normal

Pathology: Snapping Hip Syndrome • Joint abnormalities • Painful snap with hip motion • Bursal pathology • Intraarticular • Muscle and tendon injury • Extraarticular: • Snapping hip syndrome – Anterior: iliopsoas tendon • Miscellaneous pathology – Lateral: or gluteus maximus

11 Iliopsoas Complex A Snapping Hip Syndrome: iliopsoas AIIS • Image long axis to inguinal ligament superior A Ilium to femoral head B • Extension of flexed abducted and externally rotated hip • Abrupt movement of iliopsoas as iliacus muscle interposed between tendon and

Pubis bone moves Red: psoas major Femoral Deslandes et al. AJR 2008; 190:576 Orange: medial iliacus fibers Head Short Axis Purple: lateral iliacus fibers From: Guillin R. et al. Eur Rad 2009; 19:995

Snapping Hip Syndrome: iliopsoas Snapping Hip: lateral • Transverse over greater trochanter • Hip external rotation / flexion • Abrupt motion of iliotibial tract or gluteus maximus over greater trochanter

Snapping Gluteus Maximus / Iliotibial Band

Gluteus Iliotibial Band Medius TFL Gluteus Maximus Pathology: Gluteus Maximus Gmin • Joint abnormalities • Bursal pathology • Muscle and tendon injury • Snapping hip syndrome • Miscellaneous pathology

12 Polymyositis: sartorius Inflammatory Myositis • Acute: variable echogenicity, swollen • Late: – Hyperechoic: fatty infiltration A – Decreased size V • Possible hyperemia • Infection, dermatomyositis, polymyositis Normal Abnormal Transverse

Transection Transection Neuroma: Neuroma: • Neuroma formation: sciatic – Disorganized and tangled nerve end – Normal response to nerve transection – US important to determine if symptomatic

J Clin Ultrasound 1997; 25:85

Lymph Node: Lymph Node: malignant • Normal: echogenic hilum • Gray scale: – Interfaces with fluid-filled sinuses – Absent echogenic hilum – Not due to fat – Narrow hilum with thick cortex • Abnormal: enlarged, short axis >1.5 cm – Round shape (not oval)

Radiology 1992; 183:215 Radiology 1992; 183:215

13 Lymph Node: reactive Lymph Node: malignant • Power Doppler: – Dense vascularity – Spotted, mixed, or peripheral (not hilar) – High resistance

AJR 1998; 171:503

Lymph Node: angiosarcoma metastasis Pseudohypertrophy XX • Thigh: tensor fascia lata • Denervation: spine, chronic • Pseudomass appearance:

XX – Enlarged muscle – Fat infiltration

Petersilge, J Comput Assist Tomogr 1995; 19:596

Tensor Fascia Lata: pseudohypertrophy Tensor Fascia Lata: pseudohypertrophy

Transverse Longitudinal

14 Take-home points: hip

• Effusion: anterior hip • Greater trochanteric pain syndrome: – Not bursitis, usually tendinosis • Trochanter anatomy: facets • Snapping hip syndrome – Iliopsoas, iliotibial band / gluteus maximus Syllabus on line and other educational material: www.jacobsonmskus.com Twitter handle: @jjacobsn

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