Pelvis, Hip and Thigh Conditions Flashcards
What is the aetiology of pelvic fracture?
- High energy injuries in the young - typically RTA or fall from height
- Frailty fractures of older osteoporotic bone
What is the pathophysiology of pelvic fracture?
- Bony ring disruption usually affects more than one site, so they are usually multiple (either bones or symphysis/SI joints)
- Joints more likely to be affected in high energy injuries
- Young-Burgess classification is used to classify pelvic ring fractures
What is the presentation of pelvic fracture?
Pain and inability to bear weight
What are the investigations for a high energy pelvic fracture?
- If pelvis is the only site of injury → x-ray first
- In polytraumatic patients → CT first
- CT can also provide details of fractures already shown by x-ray
What are the investigations for a low energy pelvic fracture?
- These fractures are often undisplaced, with normal x-rays
- CT is more sensitive than x-ray, especially when fractures start to heal
- MRI is the most sensitive - test of choice
What is the management of pelvic fractures?
- Initial management for high energy mechanisms - pelvic binder (controls circulatory loss)
- Conservative - analgesia, weight bearing as tolerated
- Operative - ORIF, external fixators, internal fixators
What is the aetiology of a pelvic soft tissue injury?
- Sports related pelvic soft tissue injury is common
- Acutely this is typically due to muscle tear or tendon avulsion
- Chronic overuse can cause bone or soft tissue pain at site of tendon or ligament attachment
- Can also occur secondary to pelvic fracture
What are the investigations of pelvic soft tissue injuries?
- US can show acute injuries affecting superficial structures
- MRI is imaging method of choice as it provides a more complete assessment of all soft tissues and bones
What is the management of pelvic soft tissue injuries?
Rest, ice, compression, elevation (RICE)
What is the aetiology of hip dislocations?
Typically due to impact during RTA or contact sports with the hip flexed
What is the pathophysiology of hip dislocations?
- Most commonly posterior
- Force is driven along the femur proximally, so femoral head typically dislocates posteriorly with an acetabular rim fracture
- Associated fractures - posterior acetabular wall, femoral
What is the presentation of hip dislocations?
Flexed, internally rotated and adducted knee
What are the investigations of hip dislocations?
- Neurovascular assessment (particularly sciatic nerve)
- X-ray
- CT after reduction if further injury suspected
What is the management of a hip dislocation?
Immediate
- Urgent reduction
- Stabilise in tractions if required
Definitive
- Fixation of associated pelvic fractures
- Fixation of other injuries in poly-trauma patients
What are the complications of a hip dislocation?
- Sciatic nerve palsy
- AVN femoral head
- Secondary OA of hip
What are the risk factors for hip fractures?
- Osteoporosis
- Smoking, alcohol use
- Malnutrition
- Neurological impairment
- Impaired vision
- Low BMI
What is the aetiology of hip fractures?
- Typical mechanism of injury is a low impact fall in the elderly
- 92% patients are over 60
- Often associated with osteoporosis
- 73% of patients are female
- Young adults - caused by high energy trauma
What is the pathophysiology of hip fractures?
- 30% mortality at one year
- Fractures are classified as either intracapsular or extracapsular
What are intracapsular hip fractures and how are they categorised?
- Occur proximal to the intertrochanteric line
- Involve the femoral head and neck
- Subdivided into subcapital and transcervical fractures
- Can be displaced or undisplaced
- Prone to femoral head AVN and non-union
- Intracapsular fractures can damage the medial femoral circumflex artery
- Intracapsular fractures are classified using the Garden classification - predicts union and risk of AVN, which influences treatment
What are the extracapsular hip fractures?
- Occur distal to the intertrochanteric line
- Subdivided into basicervical, intertrochanteric, reverse oblique and subtrochanteric fractures
- Blood supply to the head of femur is intact, so AVN and non-union is rare
What is the presentation of hip fractures?
- Hip/groin pain
- May be swelling
- Unable to weight bear
- Lower limb on affected side may be shortened and externally rotated
- Assess neurology and vascular status of the lower limb
- Assess for cognitive impairment
- Assess for any missed injuries
- Assess for dehydration (some patients may have been on the floor for a long time)
What are the investigations for hip fractures?
X-ray
- Most are easy to see on x-ray - pelvis and lateral hip
- Loss of contour of Shenton’s line in pelvic x-ray indicates hip fracture
- Fractures to femoral neck do not always cause loss of Shenton’s line
MRI
- Fractures to femoral neck do not always cause loss of Shenton’s line
- Some undisplaced fractures are subtle/invisible on x-ray
- Where clinical suspicion persists patients undergo either a repeat x-ray after 10 days or an immediate MRI
Others
- ECG
- Bloods
What is the management for a high functioning patient with a intracapsular hip fracture?
Displaced -> Total Hip Replacement
Undisplaced -> CHS screw
What is the management for a low functioning patient with a intracapsular hip fracture?
Hemi-arthroplasty
What is the management of a intertrochanteric extracapsular hip fracture?
DHS screw
What is the management of a subtrochanteric extracapsular hip fracture?
IM nail
What is idiopathic transient osteonecrosis of the hip?
Local hyperaemia and impaired venous return with marrow oedema and increased intramedullary pressure
What is the aetiology of idiopathic transient osteonecrosis of the hip?
- Higher incidence in males
- 2 groups: middle age men, pregnant women in third trimester
What is the presentation of idiopathic transient osteonecrosis of the hip?
- Progressive groin pain over several weeks
- Difficulty weight bearing
- Usually unilateral
What are the investigations of idiopathic transient osteonecrosis of the hip?
- Elevated inflammatory markers
- X-ray - osteopenia of the femoral head and neck, thinning of the cortices, preserved joint pain
- MRI - gold standard
- Bone scan
What is the management of idiopathic transient osteonecrosis of the hip?
- Self limiting condition that resolves in 6-9 months
- Analgesia
- Protected weight (crutches) bearing to avoid stress fracture
What is trochanteric bursitis?
Repetitive trauma caused by iliotibial band tracking over trochanteric bursa which causes inflammation of the bursa
What is the aetiology of trochanteric bursitis?
- Female patients
- Young runners and older patients
- May be linked to gluteal cuff syndrome
- The broad tendinous insertion of the abductor muscles (predominantly the gluteus medius) is under considerable strain and is subject to tendonitis and degeneration leading to tendon tears
What is the presentation of trochanteric bursitis?
- Pain on the lateral aspect of the hip
- Pain on palpation of the greater trochanter
- Pain on restricted abduction
What are the investigations of trochanteric bursitis?
- Clinical diagnosis
- X-rays usually unremarkable
- Visible on MRI but not usually needed
What is the management of trochanteric bursitis?
- Analgesia - NSAIDs
- Physiotherapy (to strengthen other muscles and avoid abductor weakness)
- Steroid injection
- No proven benefit from surgery
What is the aetiology of a femoral shaft fracture?
Typically high energy injuries, major trauma patients and is often associated with other injuries
What is the management of a femoral shaft fracture?
- Initial management - Thomas splint for temporary stabilisation
- Conservative management not typically used
- Operative - IM nail, plate fixation (ORIF/MIPPO)
What are the complications of a femoral shaft fracture?
- Can result in significant blood loss
- Risk of fat embolus
