Trauma and orthopaedics (3): The hip Flashcards
name the bones which fuse to form the hip
ilium
ischium
pubis
do a purpose games
3 main articulations of the hip
- 3 main articulations
- Sacroiliac joints- articulation with the sacrum
- Pubic symphysis- articulation between the left and right bones
- Hip joint- articulation with head of femur
what type of joint is the hip
Ball (femoral head) and socket (acetabulum of hip bone)
the ilium ischium and pubis are separated by
triradiate cartilage
- Fuses begins at 15-17, complete by 20-25
Acetabulum
- Socket of joint
- Where hip bones converge
- Margin of acetabulum is incomplete inferiorly- acetabulum notch (where ligaments attach to produce foramen)
factors which stabilise the hip joint
- Labrum
- Capsule
- Ligaments
the labrum
Fibrocartilaginous rim attached to margin of acetabulum.
- Increases articular contact area by 10%
- More than 50% of head of femur fits in
- Transverse acetabular ligaments strengthens inferior portion of acetabulum
- Where acetabular notch is
joint capsule
- Capsular fibres take a spiral course
- During extremes of movement the fibres are spiralled so can twist, increasing force that draws the joint in
joint ligaments
Capsule is strengthened by 3 strong ligaments
- Illiofemoral- illium and femur
- Pubofemoral- pubis and femur
- Ischiofemoral – ishium and femur
Accessory ligaments
- Ligament of heat of femur- ligamentum teres
- Transverse acetabular ligament
Hip flexion
iliopsoas
assisted. by
- rectus femoris
- sartorius
- pectineus
hip extensors
posterior muscles
- gluteus maximus
- long head of the biceps femoris
- semimembranosus
- semitendinosus
hip adduction
-
Adductor magnus
- 2 portion (adductor and hamstrings)
- Gap in muscle fibres (adductor hiatus)
- Transmits femoral vessels (popliteal fossa)
-
Adductor brevis
- Smallest (briefest)
-
Adductor longus
- Medium
hip abduction
gluteus medius
gluteus minimus
assisted by
- tensor fascia lata
- sartorius
anterior thigh muscles
do purpose games
mainly flexion and adduction
-
Quadriceps
- Rectus femoris
- Vastus lateralis
- Vastus intermedius
- Vastus medialis
- Sartorius
- Gracilis
- Pectinius
-
Adductors
- adductor magus
- adductor brevis
- adductor longus
posterior thigh muscle
do a purpose games
mainly extension and abduction
-
Hamstrings
- semimembranosus (most medial)
- semitendinosus
- bicep femoris
- long head
- and short head
-
Gluteus muscles
- gluteus maximus
- gluteus medius
- gluteus minimus
gluteus muscles (superficial)
gluteus maximus, medius and minimus
gluteus maximus innervated by
inferior gluteal nerve (i know confusing) and artery
gluteus medius and minimus innervated by
superior gluteal nerve and artery
gluteal muscles (deep)
- Lateral rotation of the femur
- Located underneath gluteus minimus
- Also stabilise the hip joint- pulling the femoral head into the acetabulum of the pelvis
Piriformis- important anatomical landmark
- Dived up the gluteal region into an superior and inferior part
-
Sciatic nerve usually enters the gluteal region directly inferior to the piriformis
- Visible as a flat band- 2cm wide
superior gluteal nere damage
Superior gluteal nerve supplies the gluteus medius and minimus- hip abductors
Causes
- Damaged as a complication of hip surgery
- Injections to buttock
- Fracture of greater trochanter
- Dislocation of hip join
Damage to SFN leads to:
- Weakened abduction of lower limb
- Abnormal stance phase of gait
- Trandelenburgs sign
bony landmarks of the proximal femur
hip bony landmarks
blood supply of the femoral head- major source
- Deep femoral (femoral artery)
- Medial circumflex femoral artery
- Lateral circumflex femoral artery
blood supply of the femoral head- minor source (adult)
Ligamentum teres artery- branch of the obturator artery (via ligament of head of femur/ligamentum teres)
Blood supply to the femoral head in children vs adults
In the child, the artery of the ligamentum teres is the major blood supply to the femoral epiphysis (femoral head).
In the adult, after epiphyseal fusion, only a small volume of the femoral head near the fovea is adequately nourished by this artery. The blood supply of the remainder of the femoral head arises primarily from the ascending cervical branches of the medial circumflex femoral artery (MFCA).
Hence, disruption of the ascending cervical branches (retinacular arteries coming from the MFCA), for example in an intracapsular fracture of the femoral neck, carries a high risk of avascular necrosis of the bone.
areas in the hip region
lumbar plexus
sacral plexus
Lumbar plexus
sacral plexus
‘Salmon is so perfectily pink’
osteology of the femur
do purpose games
- Longest bone in the body
- Can be divided into 3 parts
- Proximal
- Shaft and distal
shaft of the femur
OA of the hip
degenerative joint disease characterised by loss of articular cartilage.
The hip is the second most commonly affected joint, with the knee the most.
RF for hip OA
- Systemic – Increasing age (>45 yrs), obesity, female gender, genetic factors*, vitamin D deficiency
- Local – History of trauma to the hip, anatomic abnormalities, muscle weakness or joint laxity, participation in high impact sports
presentation of Hip OA
- pain in the groin
- aggravated by weight-bearing
- improved by rest
- better in mornings
- stiffness
- grinding
- antalgic gait (trendelenburg gait)
- passive movement painful and range of motion reduced
DD for hip OA
- trochanteric bursitis
- sciatic
- femoral neck fracture
investigations for Hip OA
X-RAY-LOSS
- loss of joint space
- Osteophyte formation
- Sclerosis of the subchondral bone
- Subchondral bone cysts
conservative management of hip OA
- analgeisa (WHO analgesic ladder) to ensure mobility and QoL
- weight loss
- exercise
- smoking cessation
- physio
surgical intervention for hip OA
if conservative fails
either
- total hip replacement
- hemiarthroplasty
surgical approaches for hip replacement
-
Posterior Approach – The most common approach, as rehabilitation is often fast due to preservation of the abductor mechanism, minimising the risk of abductor dysfunction post-operatively
- There is the greatest risk of causing damage to the sciatic nerve and of dislocation
-
Anterolateral Approach (Modified Hardinge approach) – The abductor mechanism is detached to allow excessive adduction and thus full exposure of the acetabulum
- A merit of this method is that the superior retinacular vessels are not interrupted lowering the risk of avascular necrosis, however there is a risk of damage to the superior gluteal nerve
- Anterior Approach (Smith-Petersen approach) – This approach is rarely used in adult arthroplasty in the UK, most commonly used in open washouts of infected native hips
Common post-operative complications after hip replacement
include thromboembolic disease, bleeding, dislocation, infection, loosening of the prosthesis, and leg length discrepancy.
Hip fracture RF
- More common in Caucasian women 70-90 years
- Risk increases with age
- Risk factors
- Medical illness
- Drugs e.g. sedatives
- Dementia
- Physical disability
- Lack of exercise
- Visual impairment
- Cardiac arrhythmias
- Parkinsons
- Electrolyte imbalance
- Neuromuscular
- Loss of padding
- Loss of bone strength
- Corticosteroids
- Smoking
- Vit d deficiency
- Calcium def
- Inactivity
- Immobility
- Malnourishment
- Pagets
- Nulliparous
hip fractures are typically caused by
low energy injuries (the most common type), such as a fall in frail older patient, or high energy injuries, such as a road traffic collision or fall from height and are often associated with other significant injuries.
presentation of hip fracture
- Pain in groinm thigh or referred to the knee
- Unable to weight bear
- Leg shortened and externally rotated
- May only be trivial injury
- May still be weight bearing
- Fracture may occur prior to fall
distal neurovascular deficits are rare in isolated neck of femur fracture
investigation for hip fracture
- X ray
- AP pelvis
- Lateral
- Full length femur- if suggestion of pathology e.g. cancer
- routine bloods: FBC, A and E, coagulation screen, group and save and Creatine kinase (CK)
- urine DIP, CXR and ECG to assess reason for fall and pre-op assessment
NOF fractures can be classified as
intra-capsular
extracapsular
intracapsular NOF
from the subcapital region of the femoral head to basocervical region of the femoral neck, immediately proximal to the trochanters
extracapsular fracture
Extra-capsular – outside the capsule, subdivided into:
- Inter-trochanteric, which are between the greater trochanter and the lesser trochanter
- Sub-tronchanteric, which are from the lesser trochanter to 5cm distal to this point
blood supply to the NOF
Retrograde, passing from distal to proximal along the femoral neck to the femoral head.
This is predominantly through the medial circumflex femoral artery, which lies directly on the intra-capsular femoral neck.
Consequently, displaced intra-capsular fractures disrupt the blood supply to the femoral head and, therefore, the femoral head will undergo avascular necrosis (even if the hip is fixed). Patients with a displaced intra-capsular fracture therefore require joint replacement (arthroplasty), rather than fixation.
intracapsular fractures can be further classifef by
Garden classification
why order a Creatinine kinase test for NOF
if a long lie time could have occurred, a creatinine kinase (CK) level would be recommended to assess for any significant rhabdomyolysis.
management of NOF
- A-E to stabilise patient
- adequare anagesia
- definitve surical management
surgical options for hip fracture
non-op conservative management of NOF
rarely recommended, as the benefits of surgical intervention nearly always outweigh the potential conservative management.
post op complications of hip surgery
pain, bleeding, leg-length discrepancies, and potential neurovascular damage, all of which should be consented for pre-operatively.
avascular necrosis and NOF fracture
- Bone death
- Interruption of blood supply e.g. medial femoral circumflex
- Many causes inc
- Trauma
- Idiopathic
- Steroids
- Alcohol
- Presentation
- Severe pain
- More sudden onset than OA
internal fixation for NOF pros and cons
Internal fixation for intracapsular fracture
-
Pros
- Preserve femoral head (reduced chance of acetabular erosion)
- Lower refracture
- Lower risk of infection, blood loss
- Avoids disclocation
- Lower mortality
- Shorter operative
-
Cons
- Non union 20-30%
- AVN 10-20%
- Re-op rates 25-30%
Hemiarthroplasty/arthroplasty for NOF pros and cons
for intracapsular fracture
- Pros
- Avoids non union
- Avoids AVN
- Re-operation rates lower
- Cons
- Infection
- Dislocation
- Acetabular erosion
- Loosing
- Refracture
- longer
image of garden classification
describe: Garden stage III NOF fracture
complete fracture, partial displacement
femoral shaft fracture cause and presentation
cause
- hight energy trauma
- may be open or associated with neurovascular injury due to high impact
presentation
- pain and swelling
- unable to weight bear
- deformity
- look for open
- neuro exam
femoral shaft fracture investigations and management
investigations
- ATLS protocol
- urgent bloods (coag, group and save)
- imaging
- plain film radiograph
- CT if polytrauma suspected
management
- A-E (via ATLS)
- adequate analgesia (opioid +- regional blockade e.g. fascia iliaca block)
- immediate reduction and immobilisation
- using in line traction to ensure appropriate haematoma formation and reduce pain
Traction Splinting
Traction splinting, such as a Kendrick traction splint, are used in suspected or isolated fractures of the mid-shaft femur, acting to hold the femur in correct position against action of the large thigh muscle mass.
These are most commonly used in the pre-hospital setting and importantly are not recommended to remain in place any longer than absolutely necessary, due to the risk of skin necrosis at the groin. Traction splints should be changed to skin traction by an orthopaedic specialist as soon as possible.
Contraindications for traction splinting include hip or pelvic fractures, supracondylar fractures, fractures of ankle or foot, or partial amputation.
surgical management of femoral shaft fracture
surgically fixed within 38 hours (sooner if open)
- antegratde intramedullary nail
in unstable polytrauma
- external fixation (delayed conversion to intramedullary nail) to ensure patient is physiologically optimised
Common complications following femoral shaft fracture include:
-
Nerve injury or vascular injury
- Pudendal nerve injury (around 10%) or femoral nerve injury (rare)
-
Mal-union (or rotational mal-alignment), delayed union, or non-union
- Mal-union occurs in around 30% and 10% of proximal and distal fractures respectively
- Infection, especially with open fractures
- Fat embolism
distal femur fractures
fractures extending from the distal metaphyseal-diaphyseal junction of the femur to the articular surface of the femoral condyles.
classification of distal femur fracture
The classification is commonly used to classify distal femur fractures into extra-articular (type A), partial articular (type B), and complete articular (type C).
presentation of distal femur fracture
- following a fall or traumatic injury
- severe pain
- inability to weight bear
- deformity, swelling and ecchymosis
- look for open fracture (ATLS)
investigation for distal femur fracture
if major trauma → ATLS
- urgent bloods (Coag, G and S, myeloma screen)
- AP and lateral plain film radiograph
managamnet of distal femur fracture
Initial management
Any significant malalignment of the fracture will warrant initial realignment in A&E (with analgesia / sedation) and then immobilised using skin traction. Any evidence of an open fracture needs to be managed accordingly.
The majority of distal femur fractures are managed surgically.
Non-operative management requires a long period of immobilisation and non-weight bearing, however is sometimes indicated for fractures with minimal displacement in a non-ambulatory or very co-morbid patient.
Surgical Management of distal femur fracture
The mainstay of surgical management for distal femur fractures is retrograde nailing or open reduction internal fixation (ORIF).
Retrograde intramedullary nailing is indicated in more proximal extra-articular fractures or simple intra-articular fractures, whilst an ORIF with a distal femoral plate is often indicated for more distal fractures or complex intra-articular fractures
In certain cases, external fixation may be used in severe comminuted or open fractures.
