Hip-Thigh-Pelvis Flashcards
What bones make up each innominate?
Ilium, pubis, ischium
What are the pelvic ligaments? (5)
Sacroiliac, iliolumbar, pubic symphisis, sacrospinous, sacrotuberous
What vasculature is relevant to pelvic anatomy?
Abdominal Aorta, Posterior venous plexus (injured during pelvic fractures)
Pelvis Imaging
AP of pelvis (trauma standard), Inlet and outlet views
What are some of the relevant landmarks in a pelvic AP?
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
Describe the Anatomy of the Hip
Socket (acetabulum) is formed by fusion of ilium, ischium and pubis. It is abducted 45* and anteverted 15*. The joint capsule is thick anteriorly.
Compare Femoral Blood supply in child vs adult
0-4 years: medial and lateral femoral circumflex and ligamentum teres; Adults: medial femoral circumflex artery
Name the five muscle groups acting on the hip
extensors, flexors, abductors, adductors, external rotators
Acetabular Labrum
acts to deepen the acetabulum and increase hip stability
Hip Examination
Inspection ( leg length discrepancy, gait abnormality, trendelnburg), Palpation, Neurovascular exam, ROM, Special tests
Trendelenburg Test
Abductor weakness causing contraleral hip drop when standing on the affected limb
FADIR
Flexion, ADduction, Internal Rotation; Positive in femoralacetabular impingement (FAI)
FABER
Flexion, ABduction, External Rotation; Positive for SI joint disease
Ober
Lateral decubitis, hip extended then abducted; Tight IT Band
FAI (Femoralacetabular Impingement)
characterized by abnormal contact b/n femur and acetabulum. 2 types: Cam impingement and Pincer Impingement; premature hip degradation
Cam Impingement
Type of FAI that is femur based due to broad femoral neck (young athletes) and usually involves superolateral aspect; AP Hip: pistol grip deformity
Pincer Impingement
Type of FAI that is acetabular based due to anterosuperior overhang (middle-aged women); AP Hip: crossover sign
FAI Presentation
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.
What is considered a + finding on Frog-legged lateral hip?
A angle. Line 1- center of head and neck, line 2- center of head and bump. >55* indicates possible deformity
FAI Treatment
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)
Piriformis Syndrome
• 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
Snapping Hip (Coxa Saltans)
- 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
Pelvic Ring Injuries
• 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.
Young-Burgess Classification
• 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%)
Pelvic Ring Injury Evaluation
Xray: AP, Inlet, Outlet; CT; Labs
Pelvic ring Injury Treatment
Resucitation, pelvic binder, external fixation, ORIF
ORIF (treatment)
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
Acetabular Fractures
• 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
Evaluation of Acetabulum Fractures
• AP pelvis and Judet views (45° rotated) • Obturator oblique – anterior column/posterior wall • Iliac oblique – posterior column/anterior wall • CT of the pelvis
Radiograph Eval of Ace Fracture
Radiographic evaluation • Ilioischial line – posterior column • Iliopectineal line – anterior column
Non-operative Tx of Ace Fracturs
• Protected weight bearing 6-8 weeks • Indicated for high surgical risk patients • Minimally displaced or stable fractures
Hip Dislocation
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
Tx of Hip Dislocation
• Closed reduction within 6 hours • Risk of avascular necrosis (AVN) • Up to 40% • Increases with delay • Post reduction of the hip • Protected weight bearing
Femoral Neck Fracture
• 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)
Garden Classification
• Type I – incomplete, valgus impacted • Type II – complete, non-displaced • Type III – complete, partially displaced • Type IV – complete, displaced
Treatment of Femoral Neck Fractures
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)
Intertrochanteric Femur Fractures
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
Tx of Intertrochanteric Femur Fracture
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)
Femoral Shaft Fractures
• 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
Tx of Femoral Shaft Fractures
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)
Hip Osteoarthritis
• 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
Femoral Head Avascular Necrosis
• 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
Direct Avascular Femoral Head Necrosis
irradiation, trauma, blood disorders (leukemia, lymphoma), decompression sickenss, sickle cell disease
Indirect Avascular Femoral Head Necrosis
Alcoholism, hypercoaguable states, steroids, Systemic Lupus erythematosus, transplants, viral disorder, protease inhibitor, idiopathic
Evaluation and Tx of Fem Head Avascular Necrosis
Evaluation includes radiographs and MRI • Ficat Classification • Treatment • Pre-collapse: core decompression • Post-collapse: total hip arthroplasty
Total Hip Arthroplasty- Direct Anterior
• Interval between fascia lata and sartorius • Does not violate the abductor musculature • Lower risk of dislocation (compared to posterior)
Total Hip Arthroplasty- Direct Lateral
• Splits the vastus lateralis and the gluteus medius • May lead to postoperative limp
Total Hip Arthroplasty- Posterior Approach
• Releases the short external rotators • Risk of dislocation reduced with repair
Total Hip Rehab
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
Total Hip Complications
• 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
