Health condition · Clinically reviewed
Hip dislocation, an emergency where minutes and millimetres matter.
Urgent reduction, careful imaging and structured rehabilitation - the modern pathway for traumatic and post-arthroplasty hip dislocation in the UK.
Why trust this guide
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Clinically reviewed
Written by our editorial team and reviewed by a registered UK clinician before publication.
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Sourced from guidance
Checked against BOAST, BOA and peer-reviewed orthopaedic sources you can see at the end.
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Current for 2026
Reflects modern UK trauma pathways including urgent reduction, AVN surveillance and post-arthroplasty dislocation management.
Key facts
Hip dislocation at a glance.
The essentials, in plain English - what it is, the main causes, and how UK trauma teams manage it today.
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What it is
The femoral head is displaced out of the acetabular socket. A time-critical orthopaedic emergency needing rapid reduction.
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Traumatic dislocation
Most often high-energy injury - posterior dislocation (about 90%) from a dashboard-style impact with the hip flexed.
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Post-arthroplasty
The commonest non-traumatic cause - highest risk in the first three months after hip replacement.
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Congenital and paediatric
Developmental dysplasia of the hip (DDH) is a separate but related entity - screened for at birth.
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Urgent reduction
Closed reduction ideally within six hours under anaesthesia reduces the risk of avascular necrosis.
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Feared complication
Avascular necrosis of the femoral head affects roughly 15 to 40% and drives long-term outcome.
Why this guide matters
A time-critical injury, with a well-worn pathway.
The three points below shape everything from the resuscitation room to the physiotherapy gym over the months that follow.
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Reduce it early
Closed reduction within six hours under anaesthesia is the single biggest lever on avascular necrosis risk - the clock starts at the moment of injury.
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Image beyond the plain film
A CT scan looks for acetabular fractures and intra-articular fragments. MRI, in the weeks after, watches for avascular necrosis of the femoral head.
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Different types, different pathways
Traumatic, post-arthroplasty, developmental and neuromuscular hip dislocation share urgency - but each has its own specialist commissioned surgical route.
How the diagnosis is made
From the resuscitation room to a clear plan.
The steps a UK trauma team will normally follow, in order - so you know what to expect and why.
Phase 1 · Assessing
Mechanism, deformity and neurovascular status
Phase 2 · Confirming
X-ray and CT imaging
Phase 3 · Preparing
MRI surveillance and MDT follow-up
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Assessing
Focused trauma history
Mechanism matters - road traffic collision with knee-to-dashboard impact, fall from height, sporting collision, or a low-energy twist after joint replacement.
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Assessing
Limb-position examination
Posterior dislocation: hip flexed, adducted and internally rotated with a shortened leg. Anterior dislocation: abducted and externally rotated.
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Assessing
Neurovascular check
Sciatic nerve function (foot drop, sensation) in posterior dislocations. Femoral pulse, nerve and vein in anterior dislocations.
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Confirming
AP pelvis and lateral hip X-ray
The first-line imaging - confirms the dislocation, direction and any obvious acetabular or femoral head fracture.
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Confirming
CT scan of the hip
Specialist-commissioned imaging after reduction to look for acetabular fractures, intra-articular fragments and joint congruity.
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Preparing
Post-reduction MRI
Assesses labral and cartilage damage and starts the clock on avascular necrosis surveillance in the weeks and months that follow.
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Preparing
MDT and follow-up plan
Orthopaedic trauma team decides on protected weight-bearing, physiotherapy referral and serial MRI intervals.
Typical timeline: from injury to reduction in hours, with imaging and MDT follow-up in the days that follow.
Symptoms
What a dislocated hip looks like.
The classic picture is unmistakable at the bedside - severe pain, a deformed leg, and features that point at once to the direction of the dislocation.
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Sudden, severe hip pain
Inability to bear weight after high-energy trauma or, in a replaced hip, after a specific movement.
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Visible deformity
The leg is held in a fixed abnormal position - the classic clue on arrival in the emergency department.
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Shortened, rotated leg
Posterior: shortened, adducted and internally rotated. Anterior: abducted and externally rotated.
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Loss of movement
Any attempted movement of the hip is exquisitely painful and usually impossible.
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Sciatic nerve signs
Weakness of ankle or toe movement, or altered sensation in the leg - a red flag in posterior dislocations.
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Femoral neurovascular signs
Pale, cool foot, absent pulse, or numbness over the front of the thigh in an anterior dislocation.
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Post-arthroplasty pattern
A replaced hip that pops out on bending, twisting or crossing the legs - especially in the first three months.
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Red flag - open injury or shock
Open wound, unstable vital signs or a cold, pulseless leg means a resuscitation-room emergency.
Treatment
How hip dislocation is treated in the UK.
Urgent reduction first, then imaging-guided decisions on surgery, protected weight-bearing and long-term surveillance for avascular necrosis.
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Urgent closed reduction
Ideally within six hours under general anaesthesia with muscle relaxation - Allis or Stimson manoeuvres are the standard techniques.
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Post-reduction imaging
Check X-ray to confirm concentric reduction, then CT to look for fractures or intra-articular fragments before mobilisation.
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Open reduction
Specialist-commissioned emergency surgery for irreducible dislocations or a trapped intra-articular fragment.
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Fracture-dislocation surgery
Acetabular or femoral head fractures with dislocation are managed by a specialist pelvic and acetabular trauma team.
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Protected weight-bearing
Partial or non-weight-bearing for weeks, guided by fracture pattern, with crutches and a graduated plan.
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Structured physiotherapy
Range-of-motion, gait retraining and hip stabiliser work - see our guide on specialist physiotherapy.
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AVN surveillance MRI
Serial MRI scans over 12 to 24 months to catch early avascular necrosis before the femoral head collapses.
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Revision arthroplasty
For recurrent post-replacement dislocation - options include dual-mobility bearings and constrained liners under a specialist commissioned surgeon.
What this guide is based on
The sources behind every claim on this page.
UK national guidance and specialist society standards, current at the time of last review.
Key references
Guidelines and standards we relied on.
A quiet reminder
This guide is for information, not medical advice.
Your orthopaedic surgeon or trauma team knows your imaging and your injury in full - they can tell you which parts apply to you. If in doubt, get seen.
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British Orthopaedic Association Standards for Trauma (BOAST). Management of traumatic hip dislocation.
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British Orthopaedic Association (BOA). Guidance on hip fracture and dislocation care.
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NICE. Fractures (complex): assessment and management (NG37).
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Royal College of Surgeons of England. Standards for the initial management of severe injuries.
Red flags
When hip dislocation needs urgent specialist input.
Every dislocated hip is urgent - but these are the features that push the pathway from routine trauma care to complex, specialist commissioned surgery.
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Sciatic nerve palsy
New foot drop or numbness in the foot after a posterior dislocation - an indication for urgent orthopaedic review and prompt reduction.
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Femoral neurovascular compromise
Absent pulse or a cold, pale leg in an anterior dislocation is a vascular emergency needing immediate senior input.
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Irreducible dislocation
Failure of closed reduction under anaesthesia means an open procedure - do not delay while trying repeated attempts.
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Intra-articular fragment
Bone or cartilage trapped in the joint prevents concentric reduction and needs specialist commissioned surgery.
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Acetabular or femoral head fracture
Fracture-dislocation patterns are managed by dedicated pelvic and acetabular teams - not by a general trauma unit alone.
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Recurrent post-arthroplasty dislocation
More than one dislocation of a replaced hip warrants revision assessment - dual-mobility or constrained bearings may be needed.
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Suspected avascular necrosis
Increasing hip pain months after reduction, with MRI change, needs specialist review before femoral head collapse.
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Paediatric or DDH concern
A dislocatable or dislocated hip in an infant is a paediatric orthopaedic emergency - see our guide to hip dysplasia.
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Neuromuscular hip at risk
Progressive migration in cerebral palsy or spinal cord injury needs surveillance - see our guide to cerebral palsy.
Living with it
A hip injury with a long shadow, and a clear roadmap.
Four things that make the biggest difference in the months after reduction - respecting the timeline, keeping physiotherapy, watching for avascular necrosis, and knowing your hip precautions.
A quiet reminder
Rehabilitation is where outcomes are won.
Reduction is the start, not the end - steady physiotherapy over months does more than any single procedure.
- 01 Recovery
Respect the timeline
Reduction is only the start - it can take three to six months to feel steady, and hip precautions matter for weeks.
- 02 Movement
Physiotherapy is non-negotiable
Structured rehabilitation restores range and stability - book the first appointment before you leave hospital.
- 03 Watch
Keep an eye on the femoral head
Avascular necrosis can appear months later - stick to your MRI follow-up appointments even if pain settles.
- 04 Replaced
Know your precautions
After a hip replacement dislocation, revisit the movements to avoid - and speak up if you feel unstable.
Frequently asked
Everything we get asked about hip dislocation.
Quick answers on emergency reduction, avascular necrosis, post-arthroplasty dislocation and return to activity.
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Is a dislocated hip an emergency?
Yes - a dislocated hip is a time-critical orthopaedic emergency. Closed reduction is ideally performed within six hours to reduce the risk of avascular necrosis of the femoral head, and the leg is fully assessed for nerve and vascular injury before anything else.
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What are the main types of hip dislocation?
Traumatic (posterior in around 90%, anterior in the remainder), post-arthroplasty (after a hip replacement), congenital and developmental (DDH), and pathological (as in cerebral palsy or spinal cord injury). Each has a different management pathway, but urgent reduction and specialist assessment are common to all.
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How is a dislocated hip put back in?
Under general anaesthesia with muscle relaxation, using a controlled manoeuvre such as the Allis or Stimson technique. A check X-ray confirms concentric reduction, and a CT scan is then used to look for fractures or intra-articular fragments before mobilisation is started.
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What is avascular necrosis and why does it matter?
Avascular necrosis is loss of blood supply to the femoral head, leading to bone collapse and secondary arthritis. It affects roughly 15 to 40% of traumatic hip dislocations and is the reason serial MRI surveillance is arranged in the months after reduction.
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What if my hip replacement keeps dislocating?
Recurrent post-arthroplasty dislocation is managed by a specialist revision surgeon. Options include a change of components, a dual-mobility bearing, or a constrained liner. Alongside surgery, physiotherapy and clear hip precautions reduce the risk of further dislocation.
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When can I go back to normal activities?
Most people follow protected weight-bearing for weeks, then progress under physiotherapy guidance over three to six months. Return to sport, driving and heavy work depends on fracture pattern, imaging findings and how the femoral head looks on follow-up MRI.
Related content
Keep reading.
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Hip fracture
Fracture patterns and pathways that often coexist with dislocation.
Learn more -
Hip dysplasia
Developmental hip disease and paediatric dislocation.
Learn more -
Hip arthritis
Long-term joint disease after AVN or fracture-dislocation.
Learn more -
Hip complications
Wider look at hip problems including instability.
Learn more -
Cerebral palsy
Neuromuscular hip at risk and surveillance.
Learn more -
Hip replacement surgery
Primary and revision arthroplasty for hip disease.
Learn more -
Hip arthroscopy
Keyhole options for labral and cartilage injury.
Learn more -
Private MRI scan
Detailed imaging for post-reduction and AVN follow-up.
Learn more