Common Conditions of the Hip Flashcards
Describe the pelvis
Each hemipelvis has 3 bones - ilium, ischium and pubis
Joined by sacrum posteriorly and pubic symphysis anteriorly
Acetabulum is socket
What is key anatomy of the femur?
Head - articulates with acetabulum
Neck - blood supply
Greater trochanter -attachment for abductor and rotators
Lesser trochanter - attachment for psoas
What is the acetubulum?
Part of pelvis
Cup shape socket
What is the labrum?
Fibrocartilaginous lining of acetabulum
Deepens socket and adds stability
Describe the profunda femoris
Branches of medial and lateral circumflex arteries
MFCA - major contributor of femoral head - ascends to head and transverse to form cruciate anastomose
LFCA - 3 branches - ascending branch to joint capsule, transverse branch to cruciate anastomosis and descending branch
What are the minor contributors to the blood supply of hip?
Artery ligamentum teres
Nutrient arteries of bone
Where does primary blood supply enter neck of femur?
Via capsule
Has clinical significance as fracture to neck of femur
Why does neck of femur fracture have clinical significance with blood supply?
If intracapsular fracture then blood supply disrupted
If extracapsular fracture then blood supply maintained
How many muscles are around the hip joint?
13 muscles
What are the function of bursae?
Fluid filled sacs
Reduce friction between tissues
Describe osteoarthritis
Degenerative change of synovial joints
Progressive loss of articular cartilage
Secondary bone changes
What is osteoarthritis characterised by?
Worsening pain and stiffness of affected joint
Limiting everyday life
Describe trochanteric bursitis
Inflammation of the fluid filled sac sandwiched between hip abductors and ITB
More females then males
What are some of the causes of trochanteric bursa?
Trauma, over use - athletes and repetitive movements, abnormal movements - distant problem like scoliosis or local like muscle wasting from surgery or hip replacement
What is the presentation of trochanteric bursitis?
Pain with point tenderness and on lateral hip
What should be looked for in examination of trochanteric bursitis?
Look for scars of previous surgery and may have wasting muscle in gluteals
Feel for tenderness over greater tuberosity
Move - worst pain in active abduction
What are the investigations used for trochanteric bursitis?
X-ray - may be normal or show OA, THR and spine abnormalities
MRI - soft tissues and fluid
US - can be therapeutic with injection and diagnostic
What is the treatment for trochanteric bursitis?
NSAIDS
Relative rest and activity modification
Physiotherapy
Injection - corticosteroids
Surgery - bursectomy rare
What is avascular necrosis?
Death of bone due to loss of blood supply
Males over females and average age is 35-50 years old
80% bilateral and 3% multifocal
What are the risk factors for avascular necrosis?
Trauma - irradiation, fracture, dislocation and iatrogenic
Systemic - idiopathic, hypercoagulable state, steroids, haematological (sickle cell, lymphoma, and leukaemia), Caisson’s disease and alcoholism
What is a trauma which can cause avascular necrosis?
Injury to femoral head blood supply - intra-capsular fractures
What is an idiopathic cause for avascular necrosis?
Intravascular coagulation is the final common pathway
What is the pathoanatomic cascade of idiopathic avascular necrosis?
Coagulation of intraosseous microcirculation - venous thrombosis - retrograde arterial occlusion - intraosseous hypertension - reduced blood flow to head - cell death - chondral fracture and collapse
What are the symptoms of avascular necrosis?
Insidious onset of groin pain
Pain with stairs, walking uphill and impact activities
Limp
What is seen on examination of avascular necrosis?
Largely normal
May replicate early arthritis - reduced range of motion and stiff joint
What imaging is done for avascular necrosis and what is seen?
X-ray
MRI - can see earlier sings like crescent sign (lytic area under chondral surface)
Later changes are architecture and femur collapse - goes to arthritic stage
What is the non-operative treatment of avascular necrosis?
Reduce weight bearing, NSAIDs, bisphosphonates, anticoagulants and physiotherapy
What is the surgical treatment of avascular necrosis?
Restore blood supply - core depression and vascularised graft
Move lesion away from weight bearing area - rotational osteotomy
Total hip replacement
What is femoracetabular impingement (FAI)?
Hip pathology in younger patients
Secondary osteoarthritis
What is femoroacetabular impingement (FAI)?
Broadly defined into 2 categories - Cam lesion and Pincer
Results in impingement of femoral neck against anterior edge of acetabulum
Describe Cam lesion of FAI
Femoral based impingement - usually young athletic males
Excess bone leading to decreased head to neck ratio and aspherical head
Abutment of lesion on edge of acetabulum - flexion
Describe FAI - pincer
Acetabulum based impingement
Usually in active females
Abnormal acetabulum leading to anterosuperior acetabular rim overhang and protrusion
Abutment of lesion on edge of acetabulum
What are associated injuries to FAI?
Labral degeneration and tears
Cartilage damage and flap tears
Secondary hip OA
What is the presentation of FAI?
Groin pain worse with flexion, mechanical symptoms - block movement and pain with certain manoeuvres (getting out chair, squatting and lunging)
What is seen on examination of FAI?
Reduced flexion and internal rotation
Positive FADIR test - flexion, adduction, and internal rotation
What are the investigations of FAI?
X-ray - identify bony pathology
MRI - useful for assessing associated conditions like labral tears and articular cartilage damage
What is the non-operative treatment of FAI?
Activity modification, NSAIDs, and physiotherapy
What is the operative treatment for FAI?
Arthroscopy - shave down defect, deal with labral tears and resect artic cartilage flaps
Open - resection, periacetabular osteotomy and hip arthroscopy (resurfacing or replacement)
What is the epidemiology of labral tears?
Most commonly anterosuperior tear
All age groups and commonly active females - pincer and more flexible
What are the causes of labral tear?
FAI, trauma, OA, dysplasia and collagen disease - Ehlers-Donlos
What is the presentation of labral tears?
Groin and hip pain
Snapping sensation
Jamming or locking
What is looked for in examination of labral tear?
Can be normal
Positive FABER - flexion, abduction, external rotation - anterior tears
What are the investigations used for labral tears?
Ensure adequate imaging
X-ray - OA and dysplasia
MRI arthrogram
Diagnostic injections under local anaesthetic
What is the non-operative treatment for labral tear?
Activity modification, NSAIDs and physio
Injection of steroids
What is the operative treatment for labral tear?
Arthroscopy - repair and resection
