USG Evaluation of Hip and Knee joint

USG EVALUATION OF HIP AND KNEE JOINTAN OVERVIEWDr. H.T.NarayanaProfessor, Dept of Radiology Sri Siddhartha Medical college TumkurChief Radiologist, Navarang Diagnostic centreBangalore 1Hip joint Conventional radiography is the main stay of diagnosis of all pathologies.USG was mostly dedicated to detect DDH of infant hip.With development and advances in the USG technology and the awareness of the capabilities of USG in the assessment of MSK disease indications have increased.2Role of USG in the Hip jointInfant Hip Pediatric hip joint diseases.Adult hip.3Infant HIP Devlopmental Dysplasia of the Hip is aspectrum of disorders. Hip can beDislocatedSubluxated Dislocatable & Subluxatable Instability Dysplastic

4DDH1-2/1000 Live birthsHip instability (phys) at birth: 1-2%Barlow JBJS19621 in 60 born with instability60% resolve in the 1st week88% resolve in 1st 2 monthsRemaining 12% are true dislocations ~1.5/10005Imaging in DDH

6Ultrasound of infant HipHigh Specificity and Sensitivity: >90%Helps in diagnosis of not only Subluxated/ Dislocated hips but also Dysplastic hipsHelps in Monitoring the treatmentReduces the need for Arthrograms / Xrays.

7Natural History

8Ultrasonographic examination

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Normal proximal Femur of infant NeckGreater trochanterNeck cartilageHead cartilaginous10Static coronal view Hip at Rest. Transducer in coronal orientation over the lateral aspect of the hip

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Normal Graf measurementsAlpha angle of bony acetabulum ( N >60)Beta - angle of cartilaginous femoral head coverage (N 50%12

Graf IIa IIc

Critical Zone HipPhysiologic Immaturity13

Graf Type III Eccentric Hip 14Type III a De-centered femoral head pressing against cartilaginous roof

Bony rim is flat, roof is poorCartilage pressed upwards15Graf Type IVHip is decentred and cartilage pressed downwards

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19Children > 2 weeks to < 6 months have ultrasound with Graf classification system ClassAlpha angle DescriptionI>60NormalII60-43Immature/DysplasticIII 6 months have X-rays.DDH - Evaluation20Indications for USG in adult HIPIntra & extra articular fluid collection including bursal and synovial pathology.Guiding aspiration and biopsy.Assessment of muscle and tendon pathology.Assessment of snapping, locking and clicking hip.Assessment of prosthetic hip.

21Hip disorders age wiseElderly - OA , Occult #5th 6th decade OA, Bursitis,3rd to 5th decade AVN, transient bone marrow edema, synovial proliferative disorders.2nd to 3rd decade snapping tendon, labral tears, Osteoid osteoma.22Hip BursaeBursae are fluid filled sacs that are located between tendons and muscles over bony prominences.Bursal inflammation - due to local friction, infection, arthropathies, direct trauma, gait abnormality, obesity, prior surgery.Trochanteric, Ilio-psoas and Ischiogluteal bursae are commonly involved.

23Hip - BursaeGreater trochanteric bursae three bursae Gluteus medius and minimus bursae lie anterior to greater trochanter and Gluteus maximus (largest) lies posterior.Ilio-psoas bursa - Lies between the hip capsule and the Iliacus & psoas major muscles. 5-7cms in length & 2-4 cms in width (largest bursa in the human body) and 15% cases communicate with hip. Ischiogluteal Bursa weavers bottom.

24Hip - bursaBursae are normally collapsed and not visualized unless enlarged pathologically.USG seen as enlarged an-hypoechoic fluid filled sacs with variable internal echoes depending on the etiologies.USG - Differentiates solid masses, inguinal hernia, undescended testis, lymphadenopathy.

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Hip Bursa Distended bursa over the greater trochanter.26Prosthetic Hip assessmentTo detect collections like haematoma / seroma, joint effusions and guide aspirations Distension of pseudo capsule >3.2mms at the native lateral femoral neck an indicator of infection.Detection of para-articular collections which can not be seen on arthrography. CT / MRI are not suitable to detect due to metallic prosthesis.27

NORMALPOST OPHIP PERIPROSTHETIC SEPSISStaph Aureus Kochs Fungal 28ASSESSMENT OF MUSCLE AND TENDON PATHALOGYHamstring tendinopathy.Avulsion of Ischial Apophysis.Injury to adductor muscles, iliopsoas, anterior superior and inferior iliac crest and their associated tendinous insertions.Instability at the site of an apophyseal avulsion.29Snapping Hip 1.External causes a. Ilio-tibial band syndrome USG & MRI2. Internal causes a. Intraarticular bodies USG & Arthrogram b. Synovial osteochondromatosis X-Ray, CT, MRI & USG c. Labral Tears USG, MR Arthrography d. Articular surface abnormality MR, X-Ray e. Intermittent subluxation of the femoral head. f. Snapping ilio-psoas Syndrome USG, bursography

30External Snapping Hip syndrome Painful and audible snap during hip motion or walking.External snapping occurs when thickened area at the posterior border of the iliotibial band or anterior edge of the gluteus maximus muscle snaps forward over the greater trochanter during dynamic hip flexion or during passive movement from adducted internally rotated hip to flexion and external rotation.Examiner can sense the snap during dynamic examination.

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HIP IN ADDUCTION &EXTENSION

ILIOTIBIAL BAND OVER THE GREATER TROCHANTERHIP IN FLEXION

ILIOTIBIAL BAND JERKS ANTERIOR TO THE GREATER TROCHANTER32

HIP IN ADDUCTION &EXTENSION Gluteus maximus is posterior to greater trochanter and partly inserted into the iliotibial band HIP IN FLEXION

GLUTEUS MAXIMUS JERKS ANTERIOR TO GREATER TROCHANTER33External snapping Ilio-Psoas tendon Ilio-psoas tendon snapping over the ilio-pectineal eminence

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Hip flexed, abductedExternally rotatedIPT moves laterallyIn relation to Iliopectineal eminenceHip in extension IPT Impinges on Iliopectineal eminenceAnd at some point Moves abruptly medially35Femoral nerve impairmentPeriniguinal region direct and indirect trauma, Hemorrhage due to coagulopathyIatrogenic causes vessel cannulation, transection or compression during internal bone fragment fixation with compression plates, during inguinal hernia repair, chronic diseases.Dx - Clinical / ENMG studies / CT or MR imaging / High resolution sonography.36

Normal femoral nerveTwo cases of femoral nerveImpairment 37Joint effusionsHypoanechoic collection with variable echogenecity depending on nature of the fluid serous / bloody / infection.Best seen along the femoral neck capsule and ilio-femoral ligament bulge away from the neck due to fluid.Difference in joint distension of >2mms between the symptomatic and normal hip.Anterior joint capsule thickening >7mms.38Hip effusion Septic arthritis US guided aspirationAVN correlate with MRI & RadiogramsInflammatory and non-inflammatory arthritis (Aseptic effusions) correlate with history & X-raysHemorrhage H/o trauma / bleeding diathesisTumors PVNS & Synovial osteochondromatosis correlate with MRI & X-Rays.

39Hip effusionAdvantages of USG in Dx & AspirationAvoiding a painful dry tap.Detection of extra articular collectionAspiration under direct visualisation.Solid masses like PVN & amyloid can be recognized and biopsied.Power Doppler distinguishes inflammatory from non-inflammatory.40

Transient Synovitis in the right hip of a child.E=Epiphysis, M=Metaphysis, C= Joint CapsuleRIGHTRIGHTRIGHTLEFT NORMAL HIP

EFFUSION41

Hip EffusionSeptic ArthritisComplex collection around the dislocated hip42

Pseudo aneurysm.US guided manual compression is the first line of treatment.US guided injection of thrombin 43Imaging of Knee Disorders of the knee are the common source of referral for imaging.Plain radiograms, MRI, CT & USG are the modalities employed.Plain X-ray and MRI are the modalities of choiceUSG indications are - to assess tendon disease, bursal inflammation, synovial abnormality or capsular disease.USG advantage are Dynamic imaging, HRSG for internal tendon structure and ability to differentiate fluid form solid masses.44Knee examination I phase patient in supine, foot on the examination table and knee flexed at 30- anterior aspect of the knee in Trans & Long planes with emphasis on Quadriceps and patellar tendon and suprapatellar recess.II phase patient in supine, leg on the table and knee fully extended. Medial and lateral aspects of the knee are imaged.III phase patient in prone, postero- medial aspect of the knee is imaged.

45Bony landmarks in the kneeLateral knee Gerdys Tubercle on Tibia. Sulcus for popliteal tendon on the femur.

Medial knee Femoral epicondyle. Sulcus for semimembranosus tendon on the posteromedial aspect of the tibia.

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Sonographic landmarks A- Gerdys tubercle and iliotibial band.B sulcus for popliteal tendon, LCL and biceps tendon.C & D MCL.E pes ansoriniusF Semimembranous tendon 47

Ist Phase - Anterior knee Quadriceps Tendon knee in flexion 20 -3048Ist Phase - Anterior knee

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Ist Phase - Anterior knee50

Ist Phase - Anterior knee Patellar Tendon51

IInd Phase - Medial collateral ligament and pes anserinus tendon52

IInd Phase Lateral collateral ligament 53

IIIrd Phase - Posterior knee54

IIIrd Phase - Semimembranosus and Gastrocnemius bursa55

IIIrd Phase - Popliteal neurovascular bundle 56

IIIrd Phase - Posterolateral corner and biceps femoris57

IIIrd Phase - Peroneal nerve58Imaging of KneeCommon clinical subgroups :- Acute injury.Chronic dysfunction.Focal masses.Anterior knee pain.Post operative knee.59USG IN Acute IDKUltrasound showed good sensitivity, ranging from 76% for the ACL to 90% for the medial meniscus, and excellent specificity, ranging from 92% for the medial meniscus to 100% for the ACL. Accuracy ranged from 86% for the ACL to 98% for the lateral meniscus. These figures were comparable to the MRI findings.

Ultrasound is a simple, accurate, inexpensive and non-invasive way of assessing internal knee disorders. There is a learning curve, but results are similar to MRI.60Knee TraumaAnterior cruciate ligament disruption seen as a hypoechoic haematoma at its femoral attachment Posterior cruciate ligament injury can be assesed through posterior approach in the popliteal fossa.61

Normal USG appearance of Posterior Cruciate Ligament62

PCL Tear 63Collateral Ligament TraumaMedial collateral ligament trauma USG reveals thickened and heterogeneous ligament.Partial tear involves meniscofemoral ligament with avulsed bony fragment.Healed femoral insertion tear result in painful calcification Pellagrini-Steida lesion.64Collateral Ligament TraumaLateral collateral ligament tear is rare and is usually associated with severe intra articular trauma.MRI is usually preferred for accurate evaluation of associated ACL injury. 65Quadriceps traumaSecond most common injury to extensor mechanism.Spectrum ranges from tendinosis to partal thickness tear to complete rupture.

Full thickness tear of the Quadriceps

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Quadriceps traumaPartial thickness tear of the Quadriceps67

Menisci Normal triangular, homogeneously echogenic with no internal heterogeneous echo changes or differences.68

Meniscal rupturelinear or echogenic areas or clefts extending to the articular margins, sudden cahnges in the contours, blunting of the medial surfaces.69

Meniscus degeneration Loss of homogeneous echo structure, linear or nodular hypoechoic / echogenic areas which do not involve an articular surface.

70Popliteal artery entrapmentIt is an uncommon entity. Prevalence of 0.16% Typically affects young athletic males who present with symptoms of calf claudication.Caused by an anomalous relationship of muscle and artery in the popliteal fossa resulting in extrinsic arterial compression. Repetitive insult to the popliteal artery can cause arterial damage and lead to aneurysm, thromboembolism and arterial thrombosis. Awareness of this entity and a high index of suspicion are important as tailored imaging studies are required to make the diagnosis and plan surgical intervention. 71

Popliteal artery entrapmentNormal popliteal artery is adjacent to and lateral to medial head of Gastrocnemius muscle, which is normally attached just superior to medial femoral condyle. 72

Medial head of gastrocnemius muscle is attached more laterally Anomalous muscle band is responsible for abnormal attachment. 73

Popliteal artery may take abnormal course mediallyFibrous band is responsible for entrapment. 74

Leg in neutral position shows normal triphasic waveform Plantar flexion of foot shows compression of popliteal artery with absence of flow 75

Medial angulation of popliteal artery course Nonocclusive acute thrombus of popliteal artery with embolization to distal tibial vessels.

Occlusion of popliteal artery76Chronic Localised Knee PainAnterior Chrondromalacia Patella.Pre & infra patellar bursal disease.Hoffas fat pad inflammation.Quadriceps tendinopathy.Patellar tendinopathy.

Medial & Lateral Meniscal tear / cyst.Intra articular ganglion.Iliotibial band friction syndrome.Pes anserinus bursitis.Peroneal neuropathy.

Posterior Bakers cyst.Semimembranosus bursitis.

77Pre & Supra patellar bursa

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Patella fracture with joint effusion79Iliotibial band friction syndrome Fibrous flat band in the lateral aspect of the thigh extending from anterolateral aspect of iliac crest to anterolateral aspect of tibia (Gerdys tubercle)Repetitive abrasion and friction of the ITB across lateral femoral condyle.Long distance runners, cyclists, weight lifters.

80Jumpers Knee chronic patellar tendinosisActivity related pain / soreness at the patellar tendon insertion into the patella.Overuse of patellar extensor mechanism.Volley ball & Basket ball players.USG widened tendon with hypoechoic areas and neovascularisation.

81Peroneal neuropathyEntrapment of common peroneal nerve in the restricted space between the bone and fascia as the nerve winds around the back of the fibular neck.

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Peroneal entrapmentPressure during sleep or cross leg position.SOLs ganglion cysts, soft tissue tumors, osseous masses, large fabella, # dislocation, cast / tight bandage83Bakers cystDistended gastrocnemiosemimembranosus bursa.Fluid originates from the knee joint.Communication between knee joint & bursa - increasing age. - thinning of the joint capsule. - synovial effusion. - increased intra-articular pressure. - internal derangements.Composite of Two bursae84Bakers cyst

Ruptured cyst Cyst with septation85Bakers cyst D/DMyxoid liposarcomaMeniscal cyst

86Rheumatoid arthritisSynovial thickening.Joint effusion.Alteration in the articular cartilage blurred margins and thinning.Bakers cyst.

USG very helpful to identify the joint involvement and to monitor the response to therapy87

Rheumatoid arthritisNormal articular cartilage Eroded and thinned out irregular cartilage

88Post-op knee Screening for infection.Rupture of extensor tendon.Detection of intra articular particles of bone, cement, metal, loosening of hardware & staples.Wear& delamination of the polyethylene liners in the TKR arthroplasty prosthesis.Evaluation of arthrofibrosis

89Knee imaging The main strength of knee ultrasound is the assessment of para-articular disease. The specific structures best suited for ultrasound assessment include tendons, muscles and ligaments, as well as periarticular soft tissue masses. Joint effusions, synovial thickening, bursal fluid collections, intra-articular loose bodies, ganglion cysts, ligament and tendons tears, tendonitis and occult fractures can be diagnosed. With experience, ultrasound is a time-efficient, economical imaging tool for assessment of the knee.

9091Thank you for your attention92