Thigh Knee SINGAPORE NOTES

Thigh and Knee Ultrasound

Stephen Bird Quadriceps Insertion Quadriceps Insertion

3 Layers • Superficial: (Rectus Femoris) • Middle: (Vastus Medialis / Vastus Lateralis) • Deep: (Vastus Intermedius)

• Partial tears commonly involve superficial layer only • Axial scans required to independently assess VM and VL involvement Quadriceps Tendon Layers Rectus Femoris Anatomy Rectus Femoris Anatomy Rectus Femoris Central Tendon Rupture Rectus Femoris Central Tendon Rupture Rectus Femoris Central Tendon Rupture Hamstring Ultrasound

Stephen Bird Hamstring

Origin : Enthesis / Tendon

Belly : MTJ x 2 / Myo-fascial Boundary

Insertion : Enthesis / Tendon

Bursae : Ischial, Semimemb, Pes Anserine

Adjacent Structures : Sciatic Nerve ,

Sacrotuberous Lig Hamstring Muscle and Tendon Units Ischial Tub

BF Medial L/H Lateral SM

BF S/H

Knee Hamstring Muscle and Tendon Units Ischial Tub

ST BF Medial L/H Lateral SM BF S/H

SN Knee Hamstring Navigation Rules

• In the standard Bakers cyst plane the Semitendinosus tendon lies stacked on top of the Semimembranosus tendon • The distal Semimembranosus tendon is short while the proximal tendon is long • The distal Semitendinosus tendon is long while the proximal tendon is short • Semitendinosus has the “inscription” Hamstring Navigation Rules

• Sciatic Nerve always sits deep to the long head of Biceps Femoris • In the proximal hamstring the Semimembranous tendon (pseudo-sciatic nerve) always sits deep to the Semitendinous muscle belly • In the distal hamstring the Long Head of Biceps Femoris tendon sits superficial to the short head muscle • Adductor Magnus forms the floor Hamstring Navigation Rules • The first muscle to form as you head distal from the iscial tuberosity is semitendinosus • The biceps femoris long head and semitendinosus unite proximally to form the conjoint tendon • The conjoint tendon occupies the medial 2/3 of the ischial tuberosity • The proximal semimembranosus tendon occupies the lateral 1/3 of the iscial tuberosity • The common peroneal nerve sits against the medial edge of the short head of biceps femoris Origins What do we see Sonographically ?

At the Ischial Tuberosity Note : C.T. = Conjoint Tendon (Semitend and Biceps Fem Long Head) Medial Lateral

C.T. BF ST

S.M.

SN What do we see Sonographically ?

1cm Below the Ischial Tuberosity

Medial C.T. Lateral

S.M. SN What do we see Sonographically ?

2cm Below the Ischial Tuberosity

Lateral Medial ST C.T.

S.M. SN What do we see Sonographically ?

3cm Below the Ischial Tuberosity

ST BF Medial (L/H) Lateral SM

Common MTJ Injury Site What do we see Sonographically ?

3cm Below the Ischial Tuberosity

Medial ST BF (L/H) Lateral

Common MTJ Injury Site What do we see Sonographically ?

• 1/3 of the way from Ischial Tuberosity to Knee

BF Medial ST Lateral (L/H)

SM SN

Adductor Magnus What do we see Sonographically ?

• 2/3 of the way from Ischial Tuberosity to Knee

ST Medial BF Lateral (L/H) SM BF (S/H)

SN What do we see Sonographically ?

• Just above the Knee

ST BF (L/H) Medial BF Lateral (S/H) SM What do we see Sonographically ?

• At the Knee

ST Medial Lateral BF SM Hamstring Origin Pathology

• Tendinosis • Enthesopathy • Avulsion with preservation of the sacrotub ligament • Complete avulsion with rupture of sacroptub ligament • Proximal MTJ tear • Proximal central tendon rupture

• Piriformis / Lateral Rotators • Sciatic Nerve • Ischial Bursa • Sacrotuberous Ligament Myofacial Vs MTJ Vs Central Tendon The MTJ Hot Spot Cohens Triangle Insertions

G T S

Pes Anserine Sartorius Gracilis Semitendinosus Pes Anserine Navigation Rules

• Follow the MCL to its distal insertion (6-7cm below medial joint line) • Observe the 3 small tendons passing superficial to the MCL in short axis • Rotate almost 90 degrees with the posterior end of the transducer a little proximal relative to the distal end • Locate one of the tendons in LAX Pes Anserine Navigation Rules

• Scan inferiorly until the tendons disappear • Slowly scan proximally identifying the 3 tendons individually • The order from proximal to distal is ST, Gr, Sart • The Pes Anserine bursa lies between the 3 tendons and the underlying MCL Biceps Femoris Insertion Intimate with FCL Semimembranosus Insertion Semimembranosus Insertion Knee

80% of patients with effusions >10mm have internal derangement. 14% of patients with effusions <10mm had derangement. Haemarthrosis

3 Layers •Superficial Layer Deep Fascia •Middle Layer Tibial Collateral Lig •Deep Layer Capsular Lig MCL Tear Pellegrini Stieda Meniscus

FCL Anatomy Bakers Cyst Anatomy