Hip orthopaedics and trauma

Question 1

What can cause secondary osteoarthritis in the hip?

Answer 1

Trauma

AVN

DDH

Perthes disease

SUFE

Question 2

Where might hip pain present?

Answer 2

Pain in groin, anterior or lateral thigh

Referred pain in the knee

Pain at night

Limp

Stiffness (morning - RA)

Reduced walking distance

Question 3

For most patients, what are the indications for total hip replacement?

Answer 3

Severe pain and disability usually with accompanying radiological changes at the hip, in patients where non-operative treatment has failed or is futile

Question 4

Why is total hip replacement not favoured in younger patients?

Answer 4

Increased risk of loosening

Increased risk of osteolysis

Question 5

What other treatments might be considered in place of total hip replacement in a younger patient?

Answer 5

Osteotomies of pelvis and/or femur

Hip resurfacing

Arthrodesis (with ORIF)

Vascularized fibular graft in early AVN

Question 6

What are some of the symptoms of hip osteoarthritis?

Answer 6

Pain in the hip joint that may include pain in the groin, outer thigh, or buttocks

Difficulty walking or walking with a limp

Pain that worsens with vigorous or extended activity

Stiffness in the hip or limited range of motion

Question 7

What are some of the symptoms of hip rheumatoid arthritis?

Answer 7

Pain in the hip joint that may include pain in the groin, outer thigh, or buttocks

Difficulty walking or walking with a limp

Stiffness in the hip or limited range of motion

Bilateral involvement

Small joints (hands, cervical spine) involvement

Question 8

How do patients with avascular necrosis tend to present?

Answer 8

Groin pain

Question 9

What can avascular necrosis of the femoral head be secondary to?

Answer 9

Alcohol abuse

Hyperlipidaemia

Thrombophilia

Question 10

Which form of imaging might be required to show early changes due to avascular necrosis?

Answer 10

MRI

Question 11

What does this image show?

Answer 11

Femoral head removed during total hip replacement with a loose flap of cartilidge (osteochondritis dessicans) due to avascular necrosis

Question 12

What are the two main causes of hip impingement?

Answer 12

Deformity of head of femur

Deformity of acetabulum

Question 13

What are the symptoms of hip impingement?

Answer 13

Stiffness in groin or front of thigh
Loss of full range of motion of hip

Pain near limit of movement of hip

Question 14

What is bone marrow oedema syndrome?

Answer 14

Transient osteoporosis

Question 15

How might bone marrow oedema syndrome of the hip present?

Answer 15

Worsening hip pain - worse on exercise
Usually unilateral

Question 16

What radiological changes occur in bone marrow oedema syndrome?

Answer 16

Osteoporotic changes on Xray

Bone inflammation on MRI

Question 17

Which patients tend to be affected by bone marrow oedema syndrome?

Answer 17

Middle aged men

Women in third trimester of pregnancy

Question 18

What is the treatment for transient osteoporosis?

Answer 18

Painkillers

Bisphosphonates

(Self-limiting)

Question 19

What kinds of hip impingement are there?

Answer 19

Question 20

What is trochanteric bursitis?

Answer 20

Painful inflammation of the bursa just superficial to the greater trochanter

Question 21

What is snapping hip syndrome?

Answer 21

A condition characterized by a snapping sensation felt when the hip is flexed and extended, which may be associated with an audible snap or pain

Question 22

Which type of snapping hip syndrome is more common?

Answer 22

Lateral extra-articular, involving the snapping of the iliotibial band, the tensor fascia lata or the tendon of the gluteus medius sliding back and forth over the greater trochanter

Question 23

What can untreated snapping hip syndome lead to?

Answer 23

Bursitis

Effusion/inflammation of the area

Muscle trauma

Question 24

What is the pain associated with trochanteric bursitis/gluteal cuff syndrome?

Answer 24

Patients have pain and tenderness in the region of the greater trochanter with pain on resisted abduction

Question 25

What is gluteal cuff syndrome?

Answer 25

Tearing, inflammation and degradation of the tendons of the abductor muscles, particularly gluteus medius, due to the immense strain they are under

Question 26

What are the treatments avaliable for trochanteric bursitis/gluteal cuff syndrome?

Answer 26

Anti-inflammatories Analgesia Physiotherapy Steroid injection

Question 27

What is the treatment for avascular nercosis?

Answer 27

Pre-collapse: drill holes can be made up the femoral neck and into the abnormal area in the head in an attempt to relieve pressure (decompression), promote healing and prevent collapse Post-collapse: total hip replacement

Question 28

What is the difference between total hip arthroplasty (THA) and total hip replacement (THR)

Answer 28

THA encompasses procedures such as hip resurfacing

Question 29

Which total hip replacement is the 'gold standard' to which all other results must be compared?

Answer 29

Cemented metal/polyethylene THR

Question 30

How long are hip replacements expected to last in a low demand older patient?

Answer 30

Cup - 15 years Stem - 20 years

Question 31

Why does loosening of hip replacements occur?

Answer 31

Wear particles from the bearing surface cause an inflammatory response at the implant-bone/cement-bone interface Macrophages ingest microscopic wear particles and release inflammatory mediators resulting in osteoclastic bone resorption

Question 32

Why are ceramic hip replacements widely used?

Answer 32

Favourable friction properties

Question 33

What problem was caused in a small number of metal-on-metal hip replacements?

Answer 33

There was a reaction to metal debris resulting in the formation of an inflammatory pseudotumour which can cause necrosis of muscle and bone

Question 34

What are the early local complications of hip replacement?

Answer 34

Infection Dislocation Nerve injury (sciatic nerve) Leg length discrepancy

Question 35

What are the late complications of a total hip replacement?

Answer 35

Early loosening Late infection (haematogenous spread from a distant site) Late dislocation (due to component wear).

Question 36

What are the extra risks associated with a revision hip replacement?

Answer 36

Bigger, more complex surgery Substantial blood lose Double the complication rate as primary procedure Poor functional outcome

Question 37

Which acetabulum fracture is associated with hip dislocation?

Answer 37

Posterior wall - this is fractured as the head of the femur is pushed through the wall

Question 38

What kind of injury in which patient is the most common for acetabulum fractures?

Answer 38

High energy injury, young patients Can be low energy injury in older patients

Question 39

What radiological investigations should be requested for an acetabulum fracture?

Answer 39

X-rays - oblique view may help as fracture can be hard to see on AP CT scan - essential for surgical planning

Question 40

How is acetabulum fracture treated? ## Footnote

Answer 40

Undisplaced or small wall fractures can be treated conservitively Displaced or unstable fractures must be treated with anatomic reduction and rigid fixation to prevent development of OA in a younger patient THR can be considered in older patients

Question 41

Which condition are hip fractures generally associated with in the aging population?

Answer 41

Osteoporosis

Question 42

Which is the most common kind of patient to present with hip fracture?

Answer 42

Over 80 years old Female Co-morbidities (cerebrovascular insufficiency, cardiac arrhythmias, postural hypotension etc.) which contribute to falls

Question 43

Which complications are common following surgical fixation of a fractured hip?

Answer 43

Chest infections Respiratory failure MI Acute renal failure DVT

Question 44

What is the mortality rate one year after fixation of a hip fracture?

Answer 44

30%

Question 45

What are the two broad classifications of hip fracture and what is the relevance of this classification?

Answer 45

Intracapsular Extracapsular Related to the blood supply: describes the liklihood of disruption to the femoral blood supply

Question 46

Which kind of hip fracture can disrupt the arterial supply of the femoral head?

Answer 46

Intra-capsular

Question 47

What is the best treatment for intracapsular hip fractures?

Answer 47

Femoral head replacement due to disruption to the arterial supply: either hemi-arthroplasty (replacing just the femoral head) or THR

Question 48

In which patients is an intracapsular hip fracture best treated with a hemi-arthroplasty?

Answer 48

Impaired cognitive function Restricted mobility This is due to greater risk of dislocation with THR

Question 49

What is the best treatment for extracapsular hip fracture?

Answer 49

Internal fixation: compression or dynamic hip screw

Question 50

What is a dynamic hip screw?

Answer 50

This consists of a large screw, inserted into the femoral head across the fracture line, and a plate with a barrel which engages with the lateral end of the screw and is fixed to the femoral shaft As the patient weight bears, the screw is allowed to slide in the barrel of the plate, which results in compression at the fracture site which promotes fracture healing

Question 51

What are the associated complications with intracapsular fracture?

Answer 51

Avascular necrosis Non-union

Question 52

What is the best treatment for subtrochanteris proximal femoral fractures?

Answer 52

Intramedullary nail - avoids further disruption to blood supply