HIP HIP DISLOCATIONDISLOCATION

Fahad zakwan Fahad zakwan MD5MD5

DefinitionDefinition• A dislocationA dislocation is an injury in which a bone is is an injury in which a bone is displaced from its proper position displaced from its proper position

Traumatic hip dislocation Traumatic hip dislocation • This usually follows a serious violence. The This usually follows a serious violence. The following are the clinical types of dislocation. following are the clinical types of dislocation.

                                i) i) AcuteAcute dislocation dislocation             ii)             ii) Old unreduced Old unreduced dislocation dislocation            iii)            iii) RecurrentRecurrent dislocation dislocation

Dislocations Of The Dislocations Of The HipHip• Complete loss of contact between the articular Complete loss of contact between the articular surfaces forming the joint.surfaces forming the joint.

Classified according to the direction Classified according to the direction of the femoral head to:of the femoral head to:• PosteriorPosterior ( (commonestcommonest).).• AnteriorAnterior..

• CentralCentral (comminuted or (comminuted or displaced fracture of acetabulumdisplaced fracture of acetabulum).).

1.1. POSTERIOR DISLOCATIONPOSTERIOR DISLOCATION

•Mechanism of injury:Mechanism of injury:Road traffic accidentRoad traffic accident when the when the victim thrown forward victim thrown forward striking the knee against the striking the knee against the dashboard with the hip and dashboard with the hip and knee flexed knee flexed forcing the head forcing the head out of the acetabulum, some out of the acetabulum, some time posterior wall fracture time posterior wall fracture happen (fracture dislocation).happen (fracture dislocation).

.Signs & Symptoms of Posterior Hip Signs & Symptoms of Posterior Hip Dislocation :Dislocation :

1. 1. painpain in the hip and buttock area. in the hip and buttock area.

2. The affected limb is 2. The affected limb is shortenedshortened, , adductedadducted, and , and internally rotatedinternally rotated, with the hip and knee held in , with the hip and knee held in slight slight flexionflexion..

3. Patient may be 3. Patient may be unable to walk unable to walk or or adduct the legadduct the leg..

4. Signs of 4. Signs of vascular or sciatic nerve injuryvascular or sciatic nerve injury may be may be present :present :- Pain in hip, buttock, and posterior leg - Pain in hip, buttock, and posterior leg - Loss of sensation in posterior leg and foot - Loss of sensation in posterior leg and foot - Loss of dorsiflexion - Loss of dorsiflexion (peroneal branch) (peroneal branch) or plantar flexion or plantar flexion (tibial branch) (tibial branch) - Loss of DTRs at the ankle.- Loss of DTRs at the ankle.- Local hematoma in vascular injury.- Local hematoma in vascular injury.

Clinical FeaturesClinical Features

• The leg is The leg is shortenedshortened, , adductedadducted, , internally internally rotatedrotated and and flexedflexed at at the hip joint.the hip joint.• Be careful if Be careful if associated with associated with fracture femur (rule).fracture femur (rule).• Always examine for Always examine for signs of sciatic nerve signs of sciatic nerve injury.injury.

Radiographic evaluationRadiographic evaluation

• An An anteroposterior (APanteroposterior (AP)) radiograph of the pelvis is essential, as radiograph of the pelvis is essential, as well as well as lateral view lateral view of the affected hip.of the affected hip.

• On the On the AP view AP view of the pelvisof the pelvis::• The femoral heads should appear similar in size, and the joint spaces should The femoral heads should appear similar in size, and the joint spaces should

be symmetric throughout. In posterior dislocations, the be symmetric throughout. In posterior dislocations, the affected femoral affected femoral head will appear smaller than the normal femoral headhead will appear smaller than the normal femoral head. In anterior . In anterior dislocation, the dislocation, the femoral head will appear slightly larger than the normal hipfemoral head will appear slightly larger than the normal hip because of magnification of the femoral head to the x-ray cassette.because of magnification of the femoral head to the x-ray cassette.

• A A lateral view lateral view of the affected hip may help of the affected hip may help distinguish a posterior distinguish a posterior from an anterior dislocation.from an anterior dislocation.

• Use of 45-degree oblique (Judet) views Use of 45-degree oblique (Judet) views of the hip may be helpful to of the hip may be helpful to ascertain the presence of osteochondral fragments, the integrity of the ascertain the presence of osteochondral fragments, the integrity of the acetabulum, and the congruence of the joint spaces. Femoral head acetabulum, and the congruence of the joint spaces. Femoral head depressions and fractures may also be seen.depressions and fractures may also be seen.

• Computed tomography (CT) scans Computed tomography (CT) scans are usually obtained following are usually obtained following closed reduction of a dislocated hip. If closed reduction is not possible closed reduction of a dislocated hip. If closed reduction is not possible and an open reduction is planned, a computed tomography scan should and an open reduction is planned, a computed tomography scan should be obtained to detect the presence of intra-articular fragments and to be obtained to detect the presence of intra-articular fragments and to rule out associated femoral head and acetabular fracturesrule out associated femoral head and acetabular fractures

• The role of magnetic resonance imaging(MRI) The role of magnetic resonance imaging(MRI) in the evaluation of in the evaluation of hip dislocations has not been established; it may prove useful in the hip dislocations has not been established; it may prove useful in the evaluation of the integrity of the labrum and the vascularity of the evaluation of the integrity of the labrum and the vascularity of the femoral head.femoral head.

ClassificationClassification

•Hip dislocations are classified Hip dislocations are classified based on:based on:

1.1.the relationship of the femoral the relationship of the femoral head to the acetabulum head to the acetabulum

2.2.whether or not associated whether or not associated fractures are present.fractures are present.

Thomson and Epstein Thomson and Epstein ClassificationClassification

of Posterior Hip Dislocationsof Posterior Hip DislocationsType IType I Pure dislocation with/without a small posterior Pure dislocation with/without a small posterior

wall fragment.wall fragment.

Type II Type II Dislocation with large posterior wall fragment.Dislocation with large posterior wall fragment.

Type III Type III Dislocation with comminuted posterior wall.Dislocation with comminuted posterior wall.

Type IV Type IV Dislocation with “acetabular floor” fractureDislocation with “acetabular floor” fracture

Type V Type V Dislocation with femoral head fracture.Dislocation with femoral head fracture.

ManagementManagement

•Dislocated hip is an Dislocated hip is an emergencyemergency..•Goal is to reduce risk of Goal is to reduce risk of •AVASCULAR NECROSIS AVASCULAR NECROSIS •DJDDJD..

•Evaluation and treatment must Evaluation and treatment must be streamlinedbe streamlined

Closed ReductionClosed Reduction• Regardless of the direction of the Regardless of the direction of the dislocation, the reduction can be dislocation, the reduction can be attempted with in-line traction attempted with in-line traction with the patient lying supine. with the patient lying supine. • The preferred method is to The preferred method is to perform a closed reduction using perform a closed reduction using general anesthesiageneral anesthesia, but if this is , but if this is not feasible, reduction under not feasible, reduction under intravenous sedationintravenous sedation is possible. is possible.

There are three There are three popular methods of popular methods of achieving closed achieving closed reduction of the hip:reduction of the hip: 1.1.The The BigelowBigelow maneuver ,maneuver , 2.2.AllisAllis maneuver maneuver and and 3.3.StimsonStimson gravity gravity techniquetechnique

Management of Posterior Hip Dislocation :Management of Posterior Hip Dislocation :

The Bigelow maneuver The Bigelow maneuver and reverse Bigelow and reverse Bigelow

maneuversmaneuversMay be performed with minimal May be performed with minimal assistance with the patient in the assistance with the patient in the supinesupine position . Place the patient position . Place the patient supine on a stretcher that is elevated supine on a stretcher that is elevated to the height of the waist of the to the height of the waist of the practitioner performing the practitioner performing the reductionreduction..

The injured hip is initially held in a position of The injured hip is initially held in a position of adduction and adduction and internal rotationinternal rotation, with one practitioner applying , with one practitioner applying longitudinal longitudinal distraction and an assistant applying pressure on the patient's distraction and an assistant applying pressure on the patient's anterior superior iliac spines anterior superior iliac spines so as to stabilize the patient's pelvis.so as to stabilize the patient's pelvis.

These have been These have been associated with associated with iatrogenic femoral neck iatrogenic femoral neck fractures and are not as fractures and are not as frequently used as frequently used as reduction techniques.reduction techniques.

.

This is most common This is most common used.used.

Under GA, place the Under GA, place the patient in supine patient in supine position.position.While While an assistant an assistant stabilizes the pelvis with stabilizes the pelvis with direct pressuredirect pressure, Flex the , Flex the hip and knee to 90° and hip and knee to 90° and pulls the thigh vertically pulls the thigh vertically upward. upward.

Allis maneuverAllis maneuver

• The patient is placed prone on The patient is placed prone on the stretcher with the affected the stretcher with the affected leg hanging off the side of the leg hanging off the side of the stretcher. stretcher. • This brings the extremity into a This brings the extremity into a

position of hip flexion and knee position of hip flexion and knee flexion of 90 degrees each. In flexion of 90 degrees each. In this position, the assistant this position, the assistant immobilizes the pelvis, and the immobilizes the pelvis, and the surgeon applies an anteriorly surgeon applies an anteriorly directed force on the proximal directed force on the proximal calf. Gentle rotation of the limb calf. Gentle rotation of the limb may assist in reduction may assist in reduction

Stimson gravity Stimson gravity techniquetechnique

After TreatmentAfter Treatment• Type IType I: Traction for 3 weeks then partial wt. bearing.: Traction for 3 weeks then partial wt. bearing.• Type IIType II:: Open reduction and rigid fixation of Open reduction and rigid fixation of posterior wall followed by traction for 6 weeks.posterior wall followed by traction for 6 weeks.• Type IIIType III:: Traction for 6 weeks. Traction for 6 weeks.• Type IV&VType IV&V: : closed reduction may lead to automatic closed reduction may lead to automatic reduction of the fractures, if not open reduction and reduction of the fractures, if not open reduction and internal fixation followed by traction for 6 weeks.internal fixation followed by traction for 6 weeks.• Full weight bearing allowed only after 12 weeks.Full weight bearing allowed only after 12 weeks.

Complications of Posterior Hip Complications of Posterior Hip DislocationDislocation

1. Sciatic nerve injury.1. Sciatic nerve injury.2. Vascular injury 2. Vascular injury (hematoma).(hematoma).

3. Avascular necrosis.3. Avascular necrosis.4. Osteoarthritis.4. Osteoarthritis.5. Myositis ossificans5. Myositis ossificans

.2. Anterior Hip Dislocation :2. Anterior Hip Dislocation :

•These comprise 10% to 15% of These comprise 10% to 15% of traumatic hip dislocations. traumatic hip dislocations. •They result from external rotation They result from external rotation and abduction of the hip.and abduction of the hip.•Anterior dislocation of the hip Anterior dislocation of the hip occurs from a direct occurs from a direct blow to the blow to the posterior aspectposterior aspect of the hip or, of the hip or, more commonly, from a more commonly, from a force force applied to an abducted leg applied to an abducted leg that that displace the hip anteriorly out of the displace the hip anteriorly out of the acetabulum.acetabulum.

Signs & Symptoms of Anterior Hip Dislocation :Signs & Symptoms of Anterior Hip Dislocation :

1. 1. PainPain in the hip area and in the hip area and inabilityinability to walk or adduct the legto walk or adduct the leg2. The leg is 2. The leg is externally rotatedexternally rotated, , abductedabducted, and , and extended extended at the hip.at the hip.3. The 3. The femoral head femoral head may be palpated anterior to the pelvis.may be palpated anterior to the pelvis. Signs of injury to the Signs of injury to the femoral nerve or arteryfemoral nerve or artery may be may be present:present:

femoral nerve :femoral nerve :Paresis of lower extremity Paresis of lower extremity Weak or absent DTR at knee Weak or absent DTR at knee Paresthesias of lower extremityParesthesias of lower extremity

femoral artery:femoral artery:dull aching pain, pallor, paresthesias, and coldness.dull aching pain, pallor, paresthesias, and coldness.

Anterior Dislocation: Extreme external rotation, less-pronounced abduction and flexion

Unclassical presentation (posture) ifUnclassical presentation (posture) if

1.1. Femoral head or neck Femoral head or neck fracturefracture

2.2. Femoral shaft fractureFemoral shaft fracture3.3. Obtunded patientObtunded patient

Classification Classification

Management of Anterior Hip Dislocation :Management of Anterior Hip Dislocation :

• ReductionReduction : almost identical : almost identical to posterior dislocation, except to posterior dislocation, except while the thigh is pulled while the thigh is pulled upward it should be upward it should be adducted then an assistant adducted then an assistant helps by applying lateral helps by applying lateral traction traction to the thigh.to the thigh.

Complications of Anterior Hip Complications of Anterior Hip Dislocation :Dislocation :

1.1. Avascular necrosis.Avascular necrosis.2.2. femoral nerve injury.femoral nerve injury.3.3. femoral artery femoral artery

injury.injury.

3. Central Hip Dislocation :3. Central Hip Dislocation :

The third type of hip The third type of hip dislocation is a central dislocation is a central dislocation in which a dislocation in which a direct direct impact to the lateral impact to the lateral aspect aspect of the hip of the hip forces the forces the hip centrally hip centrally through the through the acetabulum acetabulum into the pelvis. into the pelvis. This is a This is a fracture -fracture -dislocationdislocation..

Indications for Open Reduction :Indications for Open Reduction :

1. 1. IrreducibleIrreducible dislocation by closed means dislocation by closed means2. 2. PersistentPersistent instability of the joint following instability of the joint following reduction reduction (e.g fracture-dislocation of the posterior (e.g fracture-dislocation of the posterior acetabulum)acetabulum)3. 3. FractureFracture of the femoral head or shaft of the femoral head or shaft4.4.NeurovascularNeurovascular deficits that occur after closed deficits that occur after closed reductionreduction5.5.Non concentric reductionNon concentric reduction6.6.Fracture of the acetabulum or femoral head Fracture of the acetabulum or femoral head requiring excision or open reduction and internal requiring excision or open reduction and internal fixation.fixation.7.7.Ipsilateral femoral neck fractureIpsilateral femoral neck fracture..

•Management after closed or open reduction ranges Management after closed or open reduction ranges from short periods of bed rest to various durations from short periods of bed rest to various durations of skeletal traction. No correlation exists between of skeletal traction. No correlation exists between early weight bearing and osteonecrosis. Therefore, early weight bearing and osteonecrosis. Therefore, partial weight bearing is advised.partial weight bearing is advised.• If reduction is concentric and stable: If reduction is concentric and stable: A short A short

period of bed rest is followed by protected weight period of bed rest is followed by protected weight bearing for 4 to 6 weeks.bearing for 4 to 6 weeks.• If reduction is concentric but unstable: If reduction is concentric but unstable: Skeletal Skeletal

traction for 4 to 6 weeks is followed by protective traction for 4 to 6 weeks is followed by protective weight bearing.weight bearing.

PrognosisPrognosis• The outcome following hip dislocation ranges from an essentially The outcome following hip dislocation ranges from an essentially

normal hip to a severely painful and degenerated joint.normal hip to a severely painful and degenerated joint.

• Most patients 70% to 80% have good or excellent outcome in simple Most patients 70% to 80% have good or excellent outcome in simple posterior dislocations. When posterior dislocations are associated posterior dislocations. When posterior dislocations are associated with a femoral head or acetabular fracture, however, the associated with a femoral head or acetabular fracture, however, the associated fractures generally dictate the outcome.fractures generally dictate the outcome.

• Anterior dislocations of the hip are noted to have a higher incidence Anterior dislocations of the hip are noted to have a higher incidence of associated femoral head injuries (transchondral or indentation of associated femoral head injuries (transchondral or indentation types). The only patients with excellent results in most cases are types). The only patients with excellent results in most cases are those without an associated femoral head injury.those without an associated femoral head injury.

ComplicationsComplicationsOsteonecrosis:Osteonecrosis:•This is observed in 5% to 40% of injuries, with increased risk This is observed in 5% to 40% of injuries, with increased risk associated with increased duration of dislocation (>6 to 24 hours); associated with increased duration of dislocation (>6 to 24 hours); however, some authors suggest that osteonecrosis may result from the however, some authors suggest that osteonecrosis may result from the initial injury and not from prolonged dislocation. Osteonecrosis may initial injury and not from prolonged dislocation. Osteonecrosis may become clinically apparent up to 5 years after injury. Repeated become clinically apparent up to 5 years after injury. Repeated reduction attempts may also increase its incidence.reduction attempts may also increase its incidence.

Posttraumatic osteoarthritis:Posttraumatic osteoarthritis:•This is the most frequent long-term complication of hip dislocations; This is the most frequent long-term complication of hip dislocations; the incidence is dramatically higher when dislocations are associated the incidence is dramatically higher when dislocations are associated with acetabular fractures or transchondral fractures of the femoral headwith acetabular fractures or transchondral fractures of the femoral head

Recurrent dislocation:Recurrent dislocation:• This is rare (<2%), although patients with decreased femoral This is rare (<2%), although patients with decreased femoral

anteversion may sustain a recurrent posterior dislocation, whereas anteversion may sustain a recurrent posterior dislocation, whereas those with increased femoral anteversion may be prone to recurrent those with increased femoral anteversion may be prone to recurrent anterior dislocations.anterior dislocations.

Neurovascular injury: Neurovascular injury: • Sciatic nerve injury occurs in 10% to 20% of hip dislocations. It is Sciatic nerve injury occurs in 10% to 20% of hip dislocations. It is

usually caused by a stretching of the nerve from a posteriorly usually caused by a stretching of the nerve from a posteriorly dislocated head or from a displaced fracture fragment. Prognosis is dislocated head or from a displaced fracture fragment. Prognosis is unpredictable, but most patients 40% to 50% full recoveryunpredictable, but most patients 40% to 50% full recovery

• Injury to the femoral nerve and femoral vascular structures has Injury to the femoral nerve and femoral vascular structures has been reported with anterior dislocations.been reported with anterior dislocations.

Femoral head fracturesFemoral head fractures::• These occur in 10% of posterior dislocations (shear fractures) and These occur in 10% of posterior dislocations (shear fractures) and

in 25% to 75% of anterior dislocations (indentation fractures).in 25% to 75% of anterior dislocations (indentation fractures).

Heterotopic ossification:Heterotopic ossification:• This occurs in 2% of patients and is related to the initial muscular This occurs in 2% of patients and is related to the initial muscular

damage and hematoma formation. Surgery increases its incidence. damage and hematoma formation. Surgery increases its incidence. Prophylaxis choices include indomethacin for 6 weeks or use of Prophylaxis choices include indomethacin for 6 weeks or use of radiation.radiation.

Thromboembolism:Thromboembolism:• This may occur after hip dislocation owing to traction-induced This may occur after hip dislocation owing to traction-induced

intimal injury to the vasculature. Patients should be given adequate intimal injury to the vasculature. Patients should be given adequate prophylaxis consisting of compression stockings, sequential prophylaxis consisting of compression stockings, sequential compression devices, and chemoprophylaxis, particularly if they are compression devices, and chemoprophylaxis, particularly if they are placed in traction.placed in traction.