Hip-Thigh-Pelvis

Question 1

What bones make up each innominate?

Answer 1

Ilium, pubis, ischium

Question 2

What are the pelvic ligaments? (5)

Answer 2

Sacroiliac, iliolumbar, pubic symphisis, sacrospinous, sacrotuberous

Question 3

What vasculature is relevant to pelvic anatomy?

Answer 3

Abdominal Aorta, Posterior venous plexus (injured during pelvic fractures)

Question 4

Pelvis Imaging

Answer 4

AP of pelvis (trauma standard), Inlet and outlet views

Question 5

What are some of the relevant landmarks in a pelvic AP?

Answer 5

SI joint, iliac crest, ASIS, AIIS, PSIS, PIIS, Superior ramus, Obturator foramen, Ischial Tuberosity, Pubic symphisis, Fovea, Greater/lesser trochanters, Femoral head/neck/fovea, acetabulum, Greater sciatic notch, 5th Lumbar vertebrae, sacrum

Question 6

Describe the Anatomy of the Hip

Answer 6

Socket (acetabulum) is formed by fusion of ilium, ischium and pubis. It is abducted 45* and anteverted 15*. The joint capsule is thick anteriorly.

Question 7

Compare Femoral Blood supply in child vs adult

Answer 7

0-4 years: medial and lateral femoral circumflex and ligamentum teres; Adults: medial femoral circumflex artery

Question 8

Name the five muscle groups acting on the hip

Answer 8

extensors, flexors, abductors, adductors, external rotators

Question 9

Acetabular Labrum

Answer 9

acts to deepen the acetabulum and increase hip stability

Question 10

Hip Examination

Answer 10

Inspection ( leg length discrepancy, gait abnormality, trendelnburg), Palpation, Neurovascular exam, ROM, Special tests

Question 11

Trendelenburg Test

Answer 11

Abductor weakness causing contraleral hip drop when standing on the affected limb

Question 12

FADIR

Answer 12

Flexion, ADduction, Internal Rotation; Positive in femoralacetabular impingement (FAI)

Question 13

FABER

Answer 13

Flexion, ABduction, External Rotation; Positive for SI joint disease

Question 14

Ober

Answer 14

Lateral decubitis, hip extended then abducted; Tight IT Band

Question 15

FAI (Femoralacetabular Impingement)

Answer 15

characterized by abnormal contact b/n femur and acetabulum. 2 types: Cam impingement and Pincer Impingement; premature hip degradation

Question 16

Cam Impingement

Answer 16

Type of FAI that is femur based due to broad femoral neck (young athletes) and usually involves superolateral aspect; AP Hip: pistol grip deformity

Question 17

Pincer Impingement

Answer 17

Type of FAI that is acetabular based due to anterosuperior overhang (middle-aged women); AP Hip: crossover sign

Question 18

FAI Presentation

Answer 18

Sx: Hip/groin pain with flexion, sitting and occasionally mechanically. Exam: reveals limited hip flexion and internal rotation. AP Hip. Frog leg lateral view. MRI for cartilage/labrum assessment.

Question 19

What is considered a + finding on Frog-legged lateral hip?

Answer 19

A angle. Line 1- center of head and neck, line 2- center of head and bump. >55* indicates possible deformity

Question 20

FAI Treatment

Answer 20

PT, rest, NSAIDs for minimally sx. Surgical tx for sx patients WITH mechanical sx WITHOUT arthritis. Arthoscopic labral debridement/repair with osteoplasty (remove neck bump or overhang)

Question 21

Piriformis Syndrome

Answer 21

• Compression of the sciatic nerve by the piriformis muscle. • Compression occurs anterior to the piriformis • Other variations may exist • Bipartite piriformis • Aberrant sciatic nerve • Pain in posterior gluteal region with variable neurogenic symptoms • FADIR places piriformis on stretch and may reproduce symptoms. • Treatment is rest, stretching, NSAIDS, occasional injection and rarely surgery to release the piriformis

Question 22

Snapping Hip (Coxa Saltans)

Answer 22

1. External snapping hip – IT band over the greater trochanter 2. Internal snapping hip – Iliopsoas over the femoral head or iliopectineal ridge 3. Intra-articular snapping hip – loose bodies • Exam – observe IT band over GT, may hear internal snapping • X-rays and MRI to rule out other pathology. Consider dynamic ultrasound • Treat with activity modification, NSAIDS, PT • Surgery for recalcitrant cases

Question 23

Pelvic Ring Injuries

Answer 23

• Very high morbidity and mortality. • 15% for closed fractures, 50% for open fractures • High energy blunt trauma • Often associated with chest injuries, long bone fractures, spine fractures, urologic, head and abdominal injuries  • “Ring” made of sacrum and two
innominate bones stabilized by strong
ligamentous structures
• Displacement occurs when ring is
disrupted in two separate places
• Posterior sacroiliac complex is
important
• Posterior venous plexus responsible for
most hemorrhaging.

Question 24

Young-Burgess Classification

Answer 24

• APC (Anterior-Posterior compression) • I: symphysis widening 2.5 cm • III: dislocation of the SI joint • LC (Lateral Compression) • I: oblique rami fractures • II: rami fractures and ilium fracture/dislocation • III: ipsilateral LC with contralateral APC (“windswept”) • VS (Vertical Shear) • Hypovolemic shock and mortality (25%)

Question 25

Pelvic Ring Injury Evaluation

Answer 25

Xray: AP, Inlet, Outlet; CT; Labs

Question 26

Pelvic ring Injury Treatment

Answer 26

Resucitation, pelvic binder, external fixation, ORIF

Question 27

ORIF (treatment)

Answer 27

If pubic diastasis is > 2.5 cm, SI joint displacement > 1 cm, open fractures, or post-partum diastasis > 4-6 cm. • Displaced and unstable fractures • Surgical approach depends on fracture type and pattern • Clinical outcomes closely associated with reduction of the articular surface

Question 28

Acetabular Fractures

Answer 28

``` • High energy trauma in young adults or low energy falls in older adults • Anatomy • 45° lateral inclination and 15° anteversion • Supported by two “columns” of bone • Anterior and Posterior • Corona mortis – anastamosis between external iliac (epigastric) and internal iliac (obturator) arteries ```

Question 29

Evaluation of Acetabulum Fractures

Answer 29

• AP pelvis and Judet views (45° rotated) • Obturator oblique – anterior column/posterior wall • Iliac oblique – posterior column/anterior wall • CT of the pelvis

Question 30

Radiograph Eval of Ace Fracture

Answer 30

Radiographic evaluation • Ilioischial line – posterior column • Iliopectineal line – anterior column

Question 31

Non-operative Tx of Ace Fracturs

Answer 31

• Protected weight bearing 6-8 weeks • Indicated for high surgical risk patients • Minimally displaced or stable fractures

Question 32

Hip Dislocation

Answer 32

``` Rare; Posterior (90%) • Occurs with axial loading the femur with hip flexion and adduction Anterior • Abduction and external rotation of the hip • Inferior – obturator • Superior – pubic Radiographs and CT to determine direction • CT should be obtained post-reduction • Femoral head fractures, loose bodies, acetabulum fractures ```

Question 33

Tx of Hip Dislocation

Answer 33

• Closed reduction within 6 hours • Risk of avascular necrosis (AVN) • Up to 40% • Increases with delay • Post reduction of the hip • Protected weight bearing

Question 34

Femoral Neck Fracture

Answer 34

``` • U.S. has highest incidence of hip fractures • Increasing due to aging population • 25-30% mortality at one year • Closely related to pre-injury mobility • Blood supply of femoral head is through the medial femoral circumflex artery; Disrupted with fracture Presentation • Depends on the fracture pattern and displacement • Pain in hip or groin • Limb shortened and externally rotated • May present with ipsilateral femoral shaft fracture (5% of the time) ```

Question 35

Garden Classification

Answer 35

• Type I – incomplete, valgus impacted • Type II – complete, non-displaced • Type III – complete, partially displaced • Type IV – complete, displaced

Question 36

Treatment of Femoral Neck Fractures

Answer 36

Non-operative treatment (Reserved for non-surgical candidates), ORIF (Young patients with displaced fracture • Considered surgical emergency • Reduction must be anatomic to reduce risk of AVN), Cannulated screw fixation (Garden I and II in older patients), Hemiarthroplasty (partial hip replacement, Debilitated, elderly patients • Without pre-existing arthritis), Total hip arthroplasty (Garden III and IV in older patients • Results more predictable than hemiarthroplasty)

Question 37

Intertrochanteric Femur Fractures

Answer 37

Extracapsular fracture of the proximal femur between the greater and lesser trochanters • Mostly lower energy falls in older patients • Present with painful shortened, externally rotated limb • Surgical timing • Within 48 hours will decrease mortality at one year • Must be performed when medically stabilized/optimized with medical comanagement

Question 38

Tx of Intertrochanteric Femur Fracture

Answer 38

Non-operative treatment (Reserved for non-surgical candidates), Sliding hip screw (Failure related to the tip-apex distance >25 mm), Intramedullary hip screw (Equivalent outcomes • More indications in more severe fractures)

Question 39

Femoral Shaft Fractures

Answer 39

• High energy injuries, high speed motor vehicle crashes, younger patient population • Associated with femoral neck fracture (5%) • Often “missed” (up to 30%) • Evaluation similar to trauma evaluation • Present with pain in thigh • Record neurovascular examination • Radiographs • Should include entire femur including the hip

Question 40

Tx of Femoral Shaft Fractures

Answer 40

Antegrade intramedullary nail (Considered the “gold standard” • Performed within 24 hours will decrease pulmonary complications • Exception in the setting of head injury and multitrauma), Retrograde intramedullary nail (ipsilateral femoral neck fracture • Floating knee (ipsilateral tibial shaft fracture) • Ipsilateral acetabulum fracture), External fixation (Temporary fixation in multi-trauma, vascular injury, severe open fracture)

Question 41

Hip Osteoarthritis

Answer 41

• Pain in the hip and groin region leading to functional limitations • Limited ROM, pain with motion, limb shortening • Radiographs: joint space narrowing, osteophyte formation, subchondral sclerosis and cysts. • Treatment: NSAIDS, cane or stick, weight loss, activity modification, injections • If recalcitrant, consider hip resurfacing in young patients and total hip arthroplasty in older patients

Question 42

Femoral Head Avascular Necrosis

Answer 42

• Disruption of the blood supply of the femoral head leading to bone necrosis • Present in 10% of total hip arthroplasties; Bilateral in 80%; Direct or indirect

Question 43

Direct Avascular Femoral Head Necrosis

Answer 43

irradiation, trauma, blood disorders (leukemia, lymphoma), decompression sickenss, sickle cell disease

Question 44

Indirect Avascular Femoral Head Necrosis

Answer 44

Alcoholism, hypercoaguable states, steroids, Systemic Lupus erythematosus, transplants, viral disorder, protease inhibitor, idiopathic

Question 45

Evaluation and Tx of Fem Head Avascular Necrosis

Answer 45

Evaluation includes radiographs and MRI • Ficat Classification • Treatment • Pre-collapse: core decompression • Post-collapse: total hip arthroplasty

Question 46

Total Hip Arthroplasty- Direct Anterior

Answer 46

• Interval between fascia lata and sartorius • Does not violate the abductor musculature • Lower risk of dislocation (compared to posterior)

Question 47

Total Hip Arthroplasty- Direct Lateral

Answer 47

• Splits the vastus lateralis and the gluteus medius • May lead to postoperative limp

Question 48

Total Hip Arthroplasty- Posterior Approach

Answer 48

• Releases the short external rotators • Risk of dislocation reduced with repair

Question 49

Total Hip Rehab

Answer 49

Depends on approach • Posterior: avoid flexion beyond 90, extreme internal rotation, adduction beyond midline • Lateral: avoid extension, extreme external rotation, adduction • Anterior: avoid bridging, extension, extreme external rotation, adduction; Pain management with multimodal approach • Physical therapy until patient is independent with ADLs, ambulation, transfers

Question 50

Total Hip Complications

Answer 50

• Aseptic Loosening • Loosening of the femoral component due to osteolysis • Begins with prosthesis micromotion, particular wear debris, then macrophageactivated osteolysis • Pain with weightbearing • Radiographs of the hip reveal a 2 mm rim of lucency around the femoral component • Labs often normal (ESR, CRP) • Bone scan will reveal increased uptake • Treat with revision THA if symptomatic