Session 3 - Disorders of the hip Flashcards
Superior gluteal nerve injury
How can the nerve become damaged?
- a complication of hip surgery
- injections to the buttock
- fractures of the greater trochanter (site of insertion of gluteus medius)
- dislocation of the hip joint
Superior gluteal nerve injury
Name the 2 muscles that are damaged hence the action of the lower limb that is weakened
- Gluteus medius
- Gluteus minimus
Weakness in abducting the thigh at the hip
Superior gluteal nerve injury
What is the Trendelenburg sign?
Sound side sags
- when asked to stand on the injured limb, the pelvis drops on the undamaged, unsupported side
Osteoarthritis
What is the difference between primary and secondary osteoarthritis?
Primary - the cause is unknown
Secondary - there is a known precipitating cause
Osteoarthritis
Give examples of the risk factors for primary OA
- Age
- Sex (Female>Male)
- Ethnicity (Coloured > Caucs)
- Genetics (OA runs in families)
- Nutrition
Osteoarthritis
Gives some examples of specific causes of secondary OA
- Obesity
- Trauma
- Infection
- Metabolic disorders
- Haematological disorders
Osteoarthritis
What are the symptoms of OA in any joints?
- deep aching joint pain, exacerbated by use
- reduced range of motion and grinding (crepitus)
- stiffness during rest (morning stiffness <1 hour)
Osteoarthritis
Explain the pathology of Osteoarthritis
- Risk factors leads to excessive or uneven loading of the joint and damage to articular hyaline cartilage
- Increased proteoglycan synthesis by chondrocytes in an attempt to repair damaged cartilage
- flaking and fibrillation of cartilage leading to an erosion down to the subchondral bone (reduced joint space)
- Surface changes alter joint biomechanics
Osteoarthritis
Name the 3 effects that altered joint biomechanics leads to due to the surface changes in the cartilage
- Subchondral Sclerosis
(subchondral bone responds with vascular invasion and increased cellularity, becoming thickened and denser at areas of pressure) - Subchondral bone cysts
(cystic degeneration of bone) - Osteophytes
(osseous metaplasia of connective tissue occurs, leading to the irregular outgrowth of new bone)
Osteoarthritis
What are the four cardinal signs of OA on an X-ray?
- Reduced joint space
- Subchondral sclerosis
- Subchondral bone cysts
- Osteophytes
Osteoarthritis of the hip
What are the symptoms of this?
- Joint stiffness that occurs getting out of bed and when standing up after sitting down for a long time
- Pain, tenderness or swelling in the hip, gluteal and groin regions radiating to the knee (via the obturator nerve)
- Mechanical pain (pain accentuated by mobilisation or weight-bearing)
- Crepitus (a grating sound or crunching/crackling sensation of bone rubbing on bone)
- Reduced mobility e.g. difficulty walking, difficulty putting on socks and shoes
getting in and out of a car / the bath etc
Osteoarthritis of the hip
How is this diagnosed?
- clinical presentation (signs and symptoms)
- supported by X-ray changes (cardinal signs)
Osteoarthritis of the hip
What are the initial non-operative/pharmacological treatments used to manage this condition?
- Activity Modification (avoiding activities that worsen symptoms)
- Weight reduction ( if overweight)
- Stick/Walker
- Physiotherapy
Osteoarthritis of the hip
What are the pharmacological treatments used to manage this condition?
- Paracetamol, NSAIDs
- Nutritional supplements
- Corticosteroid injections ( reduce swelling)
- Viscosupplementation ( Hyaluronic acid injections)
Osteoarthritis of the hip
What are the operative treatments used to manage this condition?
Total Hip replacement
replaces the damaged surfaces with implants and helps to relieve pain and restore mobility
Fracture of the femur neck
Name the 2 classifications of fractures that occur at the proximal head of the femur
- Intracapsular (around the neck)
- Extracapsular (intertrochanteric and subtrochanteric)
Fracture of the femur neck
Why is there a high risk of avascular necrosis to head of femur due to an intracapsular fracture compared to extracapsular?
- likely to disrupt the retinacular branches of the medial femoral circumflex artery
- the Artery of the Ligamentum Teres in fovea unable to sustain the metabolic demand of the femoral head
- risk increases if the fracture is displaced
Fracture of the femur neck
In which demographic are intracapsular fractures more common and why does it occur?
- elderly, postmenopausal women with osteoporotic bone
- occur after a minor fall
Fracture of the femur neck
In which demographic are extracapsular fractures more common and why does it occur?
- the young and middle-aged population
- occur as a result of significant traumatic force (road traffic collision)
Fracture of the femur neck
What is the treatment of an intracapsular fracture in an older person?
Surgical replacement of the femoral head
- either hemiarthroplasty [femoral head only]
- or total hip replacement [head and acetabular cup]
Fracture of the femur neck
What are the symptoms of this condition?
- Reduced mobility / sudden inability to bear weight on the limb
- Pain which may be felt in the hip, groin and/or knee
Fracture of the femur neck
What are the signs of this condition during a clinical examination?
- if the fracture is displaced, the affected leg is usually shortened, abducted, and externally rotated.
- the pain worsened on palpation of the greater trochanter
- the pain made worse by rotation of the hip
Hip dislocation
State the 3 ways in which the hip joint can dislocate
- Anterior dislocation
- Posterior dislocation
- Central dislocation
Hip dislocation
What is the most common type of dislocation out of the three and why?
- Posterior dislocation
Ischiofemoral ligament present posteriorly and is the weakest of the three ligaments that hold the hip joint
Hip dislocation
What are the features of the injured limb in a posterior dislocation?
- shortened ( head of the femur is pulled upwards by the strong extensors (gluteus maximus and hamstrings) and adductors of the hip)
- flexed
- adducted
- medial rotation (anterior fibres of the gluteus medius and minimus pull on the posteriorly displaced greater trochanter)
- sciatic nerve palsy sometimes present
Hip dislocation
What are the features of the injured limb in an anterior dislocation?
- external rotation
- abduction
- slight flexion
- rarely cause damage to femoral nerve
Hip dislocation
What are the features of a central dislocation?
The head of the femur is driven into the pelvis through the acetabulum.
It is always a fracture-dislocation.
Hip dislocation
What is palpable during a rectal examination and why is there a high risk of intrapelvic haemorrhage?
The femoral head is palpable on rectal examination and there is a high risk of intrapelvic haemorrhage due to disruption of the pelvic venous plexuses
