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Not medical advice. Verify clinically important information against current local guidance.

Surgical Approaches to the Hip and Pelvis

Operative SurgeryApproaches & Principles
Approaches & PrinciplesAdvanced

Surgical Approaches to the Hip and Pelvis

An advanced orthopaedic guide to choosing and describing surgical approaches around the hip, acetabulum and pelvis, including relevant anatomy, imaging, exposure selection, operative steps and complications.

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Peer-reviewed · 2026-06-01

Surgical Approaches to the Hip and Pelvis

High-yield overview

Choose the exposure that reaches the pathology safely

Targetthe pathology decides the exposure
Intervalknow the true plane before cutting
Repairclosure is part of the approach
Approach Families
Hip arthroplasty
PatternAnterior, anterolateral, direct lateral and posterior approaches.
TreatmentChosen by surgeon experience, patient habitus, implant plan, stability needs and revision requirements.
Acetabular fracture
PatternAnterior, intrapelvic, posterior, extended or combined exposures.
TreatmentChosen by the reduction target, column involvement, quadrilateral surface displacement and femoral head status.
Pelvic ring injury
PatternAnterior ring, posterior ring, percutaneous corridors and open posterior approaches.
TreatmentChosen by haemodynamic state, instability pattern, reduction need and safe screw corridors.
Hip preservation
PatternSmith-Petersen, surgical dislocation, periacetabular and paediatric medial or anterior exposures.
TreatmentChosen to correct morphology while protecting femoral head blood supply and growth structures.
Critical Must-Knows
  • Do not start an approach description with the incision alone. Start with position, landmarks, interval, structures at risk, exposure target and closure.
  • The same skin incision can be safe or dangerous depending on where the deep dissection goes.
  • Approach choice follows the target: acetabulum, femur, femoral head, anterior ring, posterior ring or pelvic brim.
  • Danger structures should be named before the incision: LFCN, femoral nerve, femoral vessels, obturator bundle, corona mortis, sciatic nerve and superior gluteal bundle.
  • Good exposure is not the same as aggressive exposure. The safest approach gives enough access with the least avoidable soft-tissue and neurovascular harm.
Clinical Pearls
  • “
    Direct anterior hip uses the Smith-Petersen interval between sartorius and TFL; the LFCN is vulnerable near the ASIS.
  • “
    Direct lateral and anterolateral hip approaches risk abductor dysfunction and superior gluteal nerve injury if the split is too proximal.
  • “
    Posterior hip and Kocher-Langenbeck approaches require active sciatic nerve awareness and careful posterior repair when used for arthroplasty.
  • “
    Modified Stoppa gives intrapelvic access to the pelvic brim, quadrilateral surface and medial acetabular displacement, but corona mortis and obturator structures must be controlled.
Approach choice is not a popularity contest

The best approach is the one that reaches the operative target safely in that patient. A familiar approach used for the wrong fracture, wrong implant problem or wrong soft-tissue situation becomes a liability.

At a Glance Table


Primary THA
Likely target
Femoral neck, acetabulum and proximal femur
Common approach family
Anterior, anterolateral, direct lateral or posterior
Main danger
Approach-specific nerve injury, instability or abductor dysfunction
Revision THA
Likely target
Implant, cement, bone loss, trochanter or acetabulum
Common approach family
Often posterior or extensile lateral, with ETO when needed
Main danger
Sciatic nerve, abductor mechanism, bone loss and instability
Posterior wall acetabular fracture
Likely target
Posterior wall, posterior column and marginal impaction
Common approach family
Kocher-Langenbeck
Main danger
Sciatic nerve and heterotopic ossification
Anterior column acetabular fracture
Likely target
Pelvic brim and anterior column
Common approach family
Ilioinguinal, modified Stoppa or pararectus
Main danger
External iliac vessels, femoral nerve and corona mortis
Medial quadrilateral surface displacement
Likely target
Intrapelvic medial wall
Common approach family
Modified Stoppa or pararectus
Main danger
Obturator bundle and corona mortis
Pelvic ring instability
Likely target
Anterior ring, posterior ring or sacroiliac complex
Common approach family
Anterior plating, percutaneous screws, posterior fixation or lumbopelvic fixation
Main danger
Bleeding, malreduction and neural injury
Hip and Pelvis Approach Selection
ProblemLikely targetCommon approach familyMain danger
Primary THAFemoral neck, acetabulum and proximal femurAnterior, anterolateral, direct lateral or posteriorApproach-specific nerve injury, instability or abductor dysfunction
Revision THAImplant, cement, bone loss, trochanter or acetabulumOften posterior or extensile lateral, with ETO when neededSciatic nerve, abductor mechanism, bone loss and instability
Posterior wall acetabular fracturePosterior wall, posterior column and marginal impactionKocher-LangenbeckSciatic nerve and heterotopic ossification
Anterior column acetabular fracturePelvic brim and anterior columnIlioinguinal, modified Stoppa or pararectusExternal iliac vessels, femoral nerve and corona mortis
Medial quadrilateral surface displacementIntrapelvic medial wallModified Stoppa or pararectusObturator bundle and corona mortis
Pelvic ring instabilityAnterior ring, posterior ring or sacroiliac complexAnterior plating, percutaneous screws, posterior fixation or lumbopelvic fixationBleeding, malreduction and neural injury
Mnemonic

PILOTApproach Description

P
Position
Supine, lateral or prone position; table choice; fluoroscopy and reduction access.
I
Interval
True internervous or intermuscular plane, or the muscle split being used deliberately.
L
Landmarks
ASIS, greater trochanter, iliac crest, pubic symphysis, sacrum and intended incision.
O
Obstacles
Scar, obesity, open wound, vascular repair, implants, soft-tissue flap or distorted anatomy.
T
Threats
Nerves, vessels, blood supply, abductors, sciatic nerve, corona mortis and skin bridges.

Hook:A safe approach is piloted before it is performed.

Overview/Epidemiology


Hip and pelvic approaches are high-stakes because the region combines deep joints, major vessels, large nerves, powerful muscles and complex three-dimensional bony anatomy. The approach is not just a route to bone; it affects reduction quality, implant position, dislocation risk, abductor function, nerve injury, bleeding, infection risk and future revision options.

The common clinical settings are:

  • primary and revision total hip arthroplasty
  • femoral neck fracture arthroplasty
  • acetabular fracture fixation
  • pelvic ring fixation
  • hip preservation surgery
  • infection, tumour or complex reconstruction
  • paediatric hip exposure for selected conditions

The same named approach may mean different things in different settings. A Kocher-Langenbeck exposure for the posterior acetabulum is related to posterior hip exposure but is not the same operation as a routine posterior arthroplasty approach. A Smith-Petersen exposure can be used for direct anterior THA, femoral head work and some hip preservation operations, but the deep releases and objectives differ.

Name the target before naming the approach

Approach selection should start with the pathology: posterior wall, anterior column, quadrilateral surface, unstable pelvic ring, femoral head, acetabulum or femoral stem. Once the target is clear, the approach options become logical.

Anatomy/Biomechanics


The hip and pelvis are approached through a limited number of safe windows. The surgeon must know which structures are being protected and which structures are being deliberately released or repaired.

Table of structures at risk by hip and acetabular approach
The structures at risk for each hip and acetabular approach - name them before describing the incision. Direct anterior hip: the lateral femoral cutaneous nerve, and the femoral nerve and vessels medially. Lateral hip: the superior gluteal nerve and the abductor repair. Posterior hip: the sciatic nerve and the posterior capsule and short external rotators. Anterior acetabulum (ilioinguinal): the external iliac vessels, the femoral nerve and the corona mortis. Posterior acetabulum (Kocher-Langenbeck): the sciatic nerve and the superior gluteal vessels.Credit: OrthoVellum

Hip arthroplasty approach anatomy

Direct anterior
Deep plane
Sartorius and tensor fascia lata interval
Key structures
LFCN, ascending lateral femoral circumflex vessels, femoral nerve and vessels medially
Practical consequence
Low posterior instability risk but LFCN symptoms and femoral exposure challenges can occur
Anterolateral
Deep plane
Watson-Jones interval between TFL and gluteus medius
Key structures
Superior gluteal nerve, abductors, femoral nerve medially
Practical consequence
Good anterior-lateral access; abductor handling affects gait
Direct lateral
Deep plane
Split or detach anterior gluteus medius and vastus lateralis sleeve
Key structures
Superior gluteal nerve and abductor repair
Practical consequence
Stable exposure but Trendelenburg risk if abductor repair fails
Posterior
Deep plane
Gluteus maximus split and short external rotator release
Key structures
Sciatic nerve, posterior capsule, short external rotators
Practical consequence
Excellent femoral and acetabular exposure; posterior repair improves stability
Hip Arthroplasty Approaches
ApproachDeep planeKey structuresPractical consequence
Direct anteriorSartorius and tensor fascia lata intervalLFCN, ascending lateral femoral circumflex vessels, femoral nerve and vessels mediallyLow posterior instability risk but LFCN symptoms and femoral exposure challenges can occur
AnterolateralWatson-Jones interval between TFL and gluteus mediusSuperior gluteal nerve, abductors, femoral nerve mediallyGood anterior-lateral access; abductor handling affects gait
Direct lateralSplit or detach anterior gluteus medius and vastus lateralis sleeveSuperior gluteal nerve and abductor repairStable exposure but Trendelenburg risk if abductor repair fails
PosteriorGluteus maximus split and short external rotator releaseSciatic nerve, posterior capsule, short external rotatorsExcellent femoral and acetabular exposure; posterior repair improves stability

Acetabular and pelvic anatomy

The acetabulum is a ring-like structure with anterior column, posterior column, anterior wall, posterior wall and quadrilateral surface components. An approach must reach the surface that needs reduction and fixation.

Key danger structures:

  • External iliac vessels: anterior approaches and pelvic brim work.
  • Femoral nerve: lateral to femoral vessels and vulnerable in anterior windows.
  • Corona mortis: vascular connection over the superior pubic ramus; it may bleed severely if missed.
  • Obturator nerve and vessels: medial acetabular and quadrilateral surface work.
  • Sciatic nerve: posterior acetabular exposure, posterior hip dislocation and posterior column manipulation.
  • Superior gluteal bundle: exits above piriformis and can be injured with proximal posterior exposure or excessive abductor split.
Exposure must protect the next operation

Incisions, external-fixator pins and flap choices can make later definitive fixation or soft-tissue cover harder. The first approach should not compromise the reconstructive plan.

Internervous Plane


hip surgical approaches internervous planes
Internervous planes of hip approaches: only Smith-Petersen (anterior) has a true plane (femoral n. vs superior gluteal n.); Watson-Jones, Hardinge and Kocher-Langenbeck/posterior have no true internervous plane.Credit: OrthoVellum illustration

An internervous plane is safe because the muscles on either side are supplied by different nerves. Some hip and pelvic approaches are true internervous planes; others are muscle-splitting or tendon-release approaches that are safe only if the split, release and repair are controlled.

Direct anterior hip
Plane
Sartorius/femoral nerve side and TFL/superior gluteal nerve side
Why it matters
A true interval, but LFCN and femoral exposure remain important risks
Watson-Jones
Plane
TFL and gluteus medius interval
Why it matters
Useful anterolateral access; avoid drifting into abductor injury
Direct lateral
Plane
Transgluteal split or abductor sleeve
Why it matters
Not a pure internervous plane; abductor repair determines function
Posterior hip
Plane
Gluteus maximus split and short rotator release
Why it matters
Muscle split/release approach; sciatic nerve and posterior repair are key
Kocher-Langenbeck
Plane
Between gluteus maximus and abductors with short rotator release
Why it matters
Posterior acetabular access; sciatic nerve and superior gluteal bundle define the safe limits
Modified Stoppa
Plane
Extraperitoneal intrapelvic plane
Why it matters
Not an internervous limb plane; safety depends on bladder, corona mortis and obturator bundle protection
Planes and Why They Matter
ApproachPlaneWhy it matters
Direct anterior hipSartorius/femoral nerve side and TFL/superior gluteal nerve sideA true interval, but LFCN and femoral exposure remain important risks
Watson-JonesTFL and gluteus medius intervalUseful anterolateral access; avoid drifting into abductor injury
Direct lateralTransgluteal split or abductor sleeveNot a pure internervous plane; abductor repair determines function
Posterior hipGluteus maximus split and short rotator releaseMuscle split/release approach; sciatic nerve and posterior repair are key
Kocher-LangenbeckBetween gluteus maximus and abductors with short rotator releasePosterior acetabular access; sciatic nerve and superior gluteal bundle define the safe limits
Modified StoppaExtraperitoneal intrapelvic planeNot an internervous limb plane; safety depends on bladder, corona mortis and obturator bundle protection
Mnemonic

NERVEDanger Structures

N
Nerve baseline
Document sciatic, femoral, obturator and LFCN symptoms when relevant.
E
External iliac system
Respect external iliac vessels in anterior acetabular and pelvic brim surgery.
R
Retropubic vessels
Expect corona mortis during intrapelvic and superior pubic ramus work.
V
Vulnerable abductors
Protect and repair abductors in lateral and anterolateral hip approaches.
E
Exit points
Remember sciatic nerve below piriformis and superior gluteal bundle above piriformis.

Hook:Before the incision, name the structures that can change the operation.

Clinical Assessment


Clinical assessment for an approach is not a generic history; it is a surgical access assessment.

Patient factors

  • Body habitus and soft-tissue depth.
  • Prior scars and previous approaches.
  • Infection risk and skin quality.
  • Vascular disease, anticoagulation and pelvic bleeding risk.
  • Neurological baseline, especially sciatic, femoral and obturator function.
  • Bone quality and osteoporosis.
  • Ability to tolerate lateral, prone or supine positioning.

Injury or disease factors

  • Open wound location and contamination.
  • Hip dislocation direction and time to reduction.
  • Femoral head damage, marginal impaction or intra-articular fragments.
  • Acetabular column and wall involvement.
  • Pelvic ring stability and haemodynamic state.
  • Revision implants, cement, screws, plates, cages or pelvic discontinuity.

Examination points to document

  • Distal pulses and limb perfusion.
  • Femoral, sciatic, obturator and lateral femoral cutaneous nerve symptoms where relevant.
  • Abductor function if planning lateral or revision hip surgery.
  • Skin scars and planned incision conflicts.
  • Compartment or soft-tissue swelling in trauma.

Investigations


Imaging determines the target and the safe corridor.

Plain radiographs

  • AP pelvis for global alignment, hip joint status, pelvic ring asymmetry and implants.
  • AP and lateral hip for arthroplasty planning, femoral morphology and component position.
  • Judet oblique views for acetabular column and wall assessment when CT is not yet available.
  • Inlet and outlet pelvis views for pelvic ring displacement and posterior ring assessment.

CT

CT is central for acetabular and pelvic ring surgery. It shows:

  • anterior versus posterior column involvement
  • posterior wall fragment size and marginal impaction
  • quadrilateral surface displacement
  • intra-articular fragments
  • sacral fracture morphology
  • safe iliosacral and transsacral screw corridors
  • existing implant position or bone loss in revision surgery
Acetabular fracture radiographs, CT images and operative planning sequence
A worked acetabular fracture case, from planning to fixation. (a) AP pelvis and (b) axial CT define the fracture pattern and the reduction target; (c, d) the operative exposure and reduction through the chosen approach; and (e-g) post-operative radiographs and CT confirming anatomical reduction and plate-and-screw fixation - the sequence of imaging, approach selection and fixation that every acetabular plan follows.Credit: Keel MJ et al. via Eur J Trauma Emerg Surg via Open-i (NIH) (Open Access CC BY)

CT angiography

Use when there is suspected arterial injury, expanding haematoma, pelvic bleeding concern, absent pulses, revision cup migration near vessels, tumour surgery or intrapelvic hardware migration.

MRI

MRI is not routine for fracture approach selection but can help in tumour, infection, osteonecrosis, soft-tissue abscess and hip preservation planning.

Classification Systems


Classifications help define the target; they do not choose the approach alone.

Non-anatomical acetabular classification and approach selection graphic
Acetabular classification and approach selection follow the reduction target: posterior wall or column, anterior column or wall, quadrilateral surface or a complex combined pattern.Credit: OrthoVellum
Letournel-Judet acetabular classification
What it tells you
Column and wall pattern
Approach relevance
Posterior wall and posterior column favour Kocher-Langenbeck; anterior column and quadrilateral displacement favour anterior or intrapelvic exposure
AO/OTA acetabular classification
What it tells you
Fracture group and complexity
Approach relevance
Useful for communication and research; still requires CT-based reduction target planning
Young-Burgess pelvic ring classification
What it tells you
Mechanism and instability direction
Approach relevance
Helps anticipate anterior ring, posterior ring and vascular priorities
Tile/AO pelvic ring classification
What it tells you
Rotational and vertical stability
Approach relevance
Unstable posterior ring injuries require posterior fixation strategy, not anterior plating alone
Paprosky acetabular bone loss
What it tells you
Revision THA bone defect pattern
Approach relevance
May require extensile exposure, augments, cages, cup-cage, custom implant or pelvic discontinuity strategy
Classifications That Influence Approach Choice
SystemWhat it tells youApproach relevance
Letournel-Judet acetabular classificationColumn and wall patternPosterior wall and posterior column favour Kocher-Langenbeck; anterior column and quadrilateral displacement favour anterior or intrapelvic exposure
AO/OTA acetabular classificationFracture group and complexityUseful for communication and research; still requires CT-based reduction target planning
Young-Burgess pelvic ring classificationMechanism and instability directionHelps anticipate anterior ring, posterior ring and vascular priorities
Tile/AO pelvic ring classificationRotational and vertical stabilityUnstable posterior ring injuries require posterior fixation strategy, not anterior plating alone
Paprosky acetabular bone lossRevision THA bone defect patternMay require extensile exposure, augments, cages, cup-cage, custom implant or pelvic discontinuity strategy

Limitations

Classifications describe patterns, not the whole patient. Approach choice can change because of obesity, previous scars, open wounds, vascular injury, infection, surgeon experience, implant inventory, associated fractures and whether a second team is needed.

Management Algorithm


Approach selection is a sequence:

  1. Define the pathology and reduction target.
  2. Decide whether the patient needs damage-control, definitive fixation or staged reconstruction.
  3. Review imaging in axial, coronal, sagittal and three-dimensional terms.
  4. Identify danger structures and previous surgical planes.
  5. Choose the least harmful exposure that gives enough access.
  6. Plan fixation, implant removal, grafting, flap cover and closure before incision.
  7. Have an extensile or bailout plan.

Approach choice is mainly driven by surgeon experience, patient habitus, dislocation risk, femoral exposure, implant plan and ability to repair soft tissues. Anterior, lateral and posterior approaches can all produce good results when performed well.

Choose the approach that lets you reduce the displaced column or wall under direct control. Posterior wall and posterior column injuries usually need posterior access. Anterior column, quadrilateral surface and medial displacement often need anterior or intrapelvic access.

A haemodynamically unstable patient may need binder, resuscitation, packing, external fixation or angioembolisation before definitive open fixation. Definitive approach depends on anterior ring disruption, posterior ring instability and safe percutaneous corridors.

Plan the approach around implant removal, femoral exposure, acetabular bone loss, abductor status, infection, soft-tissue envelope and the need for an extended trochanteric osteotomy or intrapelvic vascular control.

A good answer includes the bailout

When describing an approach, include what you will do if exposure is inadequate: extend the approach, change position, add a second window, use trochanteric osteotomy, call vascular or plastic surgery, or stage the operation.

Patient Positioning


Positioning is part of the approach. It determines access, fluoroscopy, reduction ability, anaesthetic safety and whether a second approach remains possible.

Supine
Typical use
Direct anterior hip, ilioinguinal, modified Stoppa, anterior pelvic ring, many percutaneous pelvic screws
Checks before incision
Image intensifier access, abdominal prep, traction options and vascular access
Lateral decubitus
Typical use
Posterior THA, direct lateral THA, selected Kocher-Langenbeck exposure
Checks before incision
Pelvis must be stable; check pressure areas, sciatic nerve baseline and leg manipulation access
Prone
Typical use
Many posterior acetabular and posterior pelvic exposures
Checks before incision
Airway, abdomen free, pressure areas, fluoroscopy and ability to manage blood loss
Staged or repositioned
Typical use
Combined anterior/posterior acetabular or pelvic reconstruction
Checks before incision
Plan draping, antibiotics, imaging, blood loss and sequence before starting
Positioning Choices
PositionTypical useChecks before incision
SupineDirect anterior hip, ilioinguinal, modified Stoppa, anterior pelvic ring, many percutaneous pelvic screwsImage intensifier access, abdominal prep, traction options and vascular access
Lateral decubitusPosterior THA, direct lateral THA, selected Kocher-Langenbeck exposurePelvis must be stable; check pressure areas, sciatic nerve baseline and leg manipulation access
ProneMany posterior acetabular and posterior pelvic exposuresAirway, abdomen free, pressure areas, fluoroscopy and ability to manage blood loss
Staged or repositionedCombined anterior/posterior acetabular or pelvic reconstructionPlan draping, antibiotics, imaging, blood loss and sequence before starting
Do not position yourself out of the bailout

If a case may require vascular control, second approach, traction, external fixation, image intensifier access or conversion to arthroplasty, the starting position must allow that plan or make repositioning safe.

Approach Atlas


Direct anterior uses the anterior internervous plane between sartorius and tensor fascia lata. It is useful for supine arthroplasty and can reduce posterior instability risk, but femoral exposure can be demanding and LFCN symptoms are common.

Anterolateral uses the Watson-Jones interval and provides anterior-lateral hip access. It avoids posterior soft-tissue release but still demands abductor protection.

Direct lateral splits or detaches the anterior abductor sleeve. It is stable and extensile but can cause abductor weakness if the repair fails or the superior gluteal nerve is injured.

Posterior provides excellent femoral and acetabular access. The sciatic nerve, posterior capsule and short external rotators must be respected; posterior repair is part of modern stability strategy.

Kocher-Langenbeck is the workhorse posterior acetabular approach for posterior wall and posterior column fixation. It requires careful sciatic nerve protection and short external rotator handling.

Ilioinguinal reaches the anterior column and pelvic brim through lateral, middle and medial windows. It is demanding because the external iliac vessels, femoral nerve and inguinal canal structures are close.

Modified Stoppa provides intrapelvic access through the space of Retzius to the pelvic brim, quadrilateral surface and medial acetabular displacement. Corona mortis and obturator structures are key hazards.

Extended iliofemoral gives broad access but at the cost of greater soft-tissue injury and heterotopic ossification risk. It is reserved for selected complex patterns and experienced teams.

Anterior ring exposure often uses a Pfannenstiel or anterior intrapelvic route for symphyseal plating, ramus fixation or anterior column access.

Posterior ring fixation may be percutaneous iliosacral or transsacral screw fixation if reduction and safe corridors are adequate.

Open posterior exposure is considered for sacroiliac disruption, posterior ilium fracture, failed closed reduction or spinopelvic fixation needs.

External fixation and C-clamp are damage-control tools. They are not substitutes for definitive posterior stability when the posterior ring remains unstable.

Smith-Petersen can expose the anterior hip, femoral head-neck junction and acetabular rim for selected preservation procedures.

Surgical hip dislocation allows circumferential femoral head and acetabular access while protecting the deep branch of the medial femoral circumflex artery when performed correctly.

Periacetabular osteotomy exposure is a specialised pelvic osteotomy exposure that must protect the hip abductors, femoral nerve, vessels and acetabular blood supply.

Paediatric medial or anterior exposures are used for selected DDH or paediatric hip pathology and require growth-plate and vascular awareness.

The Extended Trochanteric Osteotomy (ETO) - the Revision Workhorse Extensile Exposure

The ETO is repeatedly referenced above ("with ETO when needed", "trochanteric osteotomy") as the bailout for revision femoral exposure but is never described - and examiners expect you to be able to explain it:

  • Indications: removal of a well-fixed cemented or cementless femoral stem, cement/distal cement-plug removal, access to a varus-remodelled or deformed proximal femur, and improved acetabular exposure in difficult revisions.
  • Key technical principle - keep the fragment vascularised: the osteotomy is lateral-based, taking roughly the lateral one-third of the femoral circumference, and the bone fragment is kept in continuity with the vastus lateralis distally and the abductors (gluteus medius) proximally - this preserves its blood supply and the abductor lever arm. The length is tailored to the stem/cement to be removed (commonly around 12-14 cm), with the distal corner rounded to reduce stress-riser fracture.
  • Repair/fixation: the trochanteric-abductor fragment is reduced and fixed back with cerclage cables/wires (often two or more), restoring abductor tension; union rates are high (typically reported around or above 90%) when the soft-tissue sleeve is preserved.
  • Pitfalls: an under-vascularised or over-thin fragment risks non-union/migration; too short an osteotomy fails to relieve the implant; a square distal corner creates a fracture stress riser.

Exam point: the ETO is a lateral-based, vastus-and-abductor-pedicled osteotomy of about one-third the femoral circumference, used to remove well-fixed stems/cement and access femoral deformity, repaired with cables with a high union rate - it is the extensile bailout for the revision femur.

Surgical Technique


The surgical technique section describes approach principles. Individual operations still require detailed procedure-specific planning.

Confirm indication, imaging, side, implants, patient position and bailout plan. Mark ASIS, iliac crest, greater trochanter, femoral shaft, pubic symphysis and sacrum where relevant.

Plan image intensifier access before sterile prep. Prep widely enough for extension, traction, vascular control or a second approach if needed. Check neurovascular baseline before and after positioning.

Position supine. Mark ASIS and tensor fascia lata. Develop the interval between sartorius medially and tensor fascia lata laterally.

Protect the LFCN by staying in the correct interval and avoiding aggressive subcutaneous dissection near ASIS. Control ascending lateral femoral circumflex branches. Expose the capsule and perform capsulotomy or capsulectomy as planned.

For femoral work, release capsule and soft tissue sufficiently to elevate the femur safely. Close fascia carefully and avoid compressive closure around the nerve region.

Position lateral or supine depending surgeon preference. Centre incision over the greater trochanter and split fascia lata in line with the femur.

Develop the anterior abductor sleeve or split, avoiding excessive proximal extension. Expose anterior capsule while protecting abductors. Repair gluteus medius, minimus and vastus sleeve securely to reduce Trendelenburg risk.

Position lateral decubitus with stable pelvic supports. Incise centred on the posterior greater trochanter and femoral shaft. Split gluteus maximus in line with fibres.

Identify and protect the sciatic nerve region with awareness and gentle retraction rather than unnecessary dissection. Tag piriformis and short external rotators as required, open posterior capsule, expose the hip and repair posterior capsule and short external rotators when feasible.

Position prone or lateral depending fracture pattern and team preference. Incise from posterior iliac region toward greater trochanter and down femoral shaft as required.

Split gluteus maximus. Identify the sciatic nerve region and release or tag short external rotators to improve safe exposure. Expose posterior column, posterior wall and retroacetabular surface. Reduce marginal impaction and wall fragments under direct vision. Avoid excessive superior dissection toward the superior gluteal bundle.

For ilioinguinal exposure, position supine, incise along the iliac crest and inguinal region, then develop lateral, middle and medial windows. Protect femoral nerve, external iliac vessels and spermatic cord or round ligament.

For modified Stoppa exposure, use a Pfannenstiel or midline lower abdominal route, enter Retzius extraperitoneally, identify corona mortis and protect bladder, obturator nerve and obturator vessels. Expose pelvic brim, quadrilateral surface and medial acetabulum.

Technique depends on resuscitation status and instability. Acute care may require binder, anterior external fixation or C-clamp. Definitive anterior ring surgery may use Pfannenstiel exposure for symphyseal plating.

Posterior ring management may use percutaneous iliosacral or transsacral screws after reduction and safe corridor confirmation, open posterior reduction for irreducible sacroiliac disruption or lumbopelvic fixation for spinopelvic dissociation.

Complications


LFCN neuropraxia
Where it occurs
Direct anterior hip
Prevention and recognition
Respect interval near ASIS; counsel that numbness or dysaesthesia can occur
Femoral nerve or vessel injury
Where it occurs
Anterior hip and anterior acetabular approaches
Prevention and recognition
Know medial danger zone, use careful retractors and avoid blind instrumentation
Sciatic nerve injury
Where it occurs
Posterior hip and posterior acetabulum
Prevention and recognition
Document baseline, avoid traction, protect during posterior column work
Abductor weakness
Where it occurs
Anterolateral and direct lateral hip
Prevention and recognition
Limit proximal split and repair abductors securely
Dislocation
Where it occurs
All THA approaches, pattern differs by approach
Prevention and recognition
Component position, soft-tissue repair, head size, offset and patient education
Corona mortis bleeding
Where it occurs
Anterior pelvis and modified Stoppa
Prevention and recognition
Identify, clip or ligate; do not sweep blindly over superior pubic ramus
Heterotopic ossification
Where it occurs
Acetabular fracture surgery, extended approaches and head injury patients
Prevention and recognition
Minimise soft-tissue trauma and consider prophylaxis according to risk and local protocol
Malreduction
Where it occurs
Acetabular and pelvic ring fixation
Prevention and recognition
Use CT planning, adequate exposure, reduction aids and intraoperative imaging
Complications by Approach Family
ComplicationWhere it occursPrevention and recognition
LFCN neuropraxiaDirect anterior hipRespect interval near ASIS; counsel that numbness or dysaesthesia can occur
Femoral nerve or vessel injuryAnterior hip and anterior acetabular approachesKnow medial danger zone, use careful retractors and avoid blind instrumentation
Sciatic nerve injuryPosterior hip and posterior acetabulumDocument baseline, avoid traction, protect during posterior column work
Abductor weaknessAnterolateral and direct lateral hipLimit proximal split and repair abductors securely
DislocationAll THA approaches, pattern differs by approachComponent position, soft-tissue repair, head size, offset and patient education
Corona mortis bleedingAnterior pelvis and modified StoppaIdentify, clip or ligate; do not sweep blindly over superior pubic ramus
Heterotopic ossificationAcetabular fracture surgery, extended approaches and head injury patientsMinimise soft-tissue trauma and consider prophylaxis according to risk and local protocol
MalreductionAcetabular and pelvic ring fixationUse CT planning, adequate exposure, reduction aids and intraoperative imaging
Heterotopic Ossification - Grade It, Risk-Stratify It, Prophylax It

The complication table lists heterotopic ossification (HO) but the examinable detail - grading, the approach-dependent risk gradient, and the actual prophylaxis options - is worth holding explicitly:

  • Grading (Brooker): I = islands of bone in soft tissue; II = bone spurs from pelvis/proximal femur with at least one cm between opposing surfaces; III = spurs with less than one cm between surfaces; IV = apparent radiographic ankylosis. Higher grades correlate with functional loss.
  • Risk is approach-dependent: HO is highest with the extended iliofemoral approach and with extensive abductor/gluteus stripping, intermediate with the Kocher-Langenbeck, and lowest with the ilioinguinal / anterior intrapelvic approaches (which spare the gluteal muscle mass). Head injury, male sex, delayed surgery and muscle debridement add risk.
  • Prophylaxis (two equally-recognised options): (1) single-dose radiotherapy (commonly around 700-800 cGy) given within roughly 24-72 hours of surgery; or (2) indomethacin or another NSAID for several weeks postoperatively. Reserve prophylaxis for higher-risk approaches/patients - weigh NSAID effects on fracture/bone healing and the practicalities of perioperative radiotherapy.

Exam point: for acetabular/hip approaches say you would grade HO by Brooker, recognise the extended-iliofemoral/abductor-stripping approaches as highest-risk (intrapelvic lowest), and offer single-dose radiotherapy or an NSAID course as prophylaxis in selected high-risk cases.

Postoperative Care


Postoperative care depends on the operation, but approach-specific points matter.

Hip arthroplasty

  • Check sciatic, femoral and peroneal nerve function.
  • Check wound, haematoma and infection risk.
  • Use approach-specific dislocation precautions where the surgeon considers them appropriate.
  • Protect abductor repair after lateral approaches according to local protocol.
  • Confirm component position and leg length on postoperative radiographs.

Acetabular and pelvic fixation

  • Repeat neurological examination after surgery.
  • Monitor haemoglobin, drains, wound swelling and pelvic bleeding risk.
  • Use postoperative CT when reduction or screw placement needs confirmation.
  • Weight-bearing depends on fracture stability, fixation quality and associated injuries.
  • Monitor for DVT, heterotopic ossification, infection, nonunion and post-traumatic arthritis.

Outcomes/Prognosis


Outcomes depend more on pathology, surgical execution and patient factors than the name of the approach alone.

For THA, modern evidence suggests that direct anterior, lateral and posterior approaches can all achieve excellent outcomes when performed by experienced surgeons. Differences tend to involve early recovery patterns, dislocation direction, nerve symptoms, abductor morbidity, fracture risk and learning curve rather than a universal winner.

For acetabular fractures, reduction quality remains a major determinant of outcome. An approach that gives inadequate reduction access is worse than a larger approach chosen deliberately. Posterior wall comminution, marginal impaction, femoral head damage, delayed surgery, nerve injury and imperfect reduction worsen prognosis.

For pelvic ring injuries, outcome is influenced by haemodynamic injury, posterior ring reduction, neurological injury, associated trauma, chronic pain and rehabilitation access.

Evidence Base


Every card below is anchored to a verified PubMed-indexed source. Read the statistics carefully: they are exam-quotable because they come from the actual papers, not from approximations.

Evidence

Direct anterior versus posterior THA - pooled cohort and RCT data

Level III (systematic review and meta-analysis)
Wang H, Liu JF, Wang F, et al. • Medicine (Baltimore) (2024)
Key Findings:
  • 33 studies, 14,478 patients (4,911 direct anterior, 9,567 posterior).
  • Direct anterior gave lower day 1 and day 2 pain scores and more cups within the Lewinnek safe zone (RR 1.13).
  • Direct anterior carried higher intraoperative fracture (OR 2.18) and lateral femoral cutaneous nerve injury (RR 7.84).
  • Dislocation rate, blood loss and heterotopic ossification did not differ significantly.
Clinical implication: Direct anterior offers earlier pain relief and component-position advantages but trades off higher intraoperative fracture and LFCN injury - counsel and select accordingly.
Verify on PubMed (PMID 39121305)
Evidence

Direct anterior versus conventional approaches - randomized-trial synthesis

Level II (meta-analysis of RCTs)
Liu R, Zhao Y, Yu Z, et al. • Journal of Orthopaedic Surgery and Research (2025)
Key Findings:
  • 17 RCTs, 1,575 patients (4 Level I, 13 Level II).
  • Direct anterior prolonged operative time by a mean of 14.5 minutes.
  • Direct anterior reduced day 1 pain and improved 1-month Harris Hip Score (MD 3.41).
  • Nerve injury risk was markedly higher with direct anterior (RR 7.37); fracture, dislocation, infection and thrombosis did not differ.
Clinical implication: Restricting to randomized data confirms the same pattern: an early-recovery benefit for direct anterior at the cost of longer surgery and more nerve injury. No approach is universally superior.
Verify on PubMed (PMID 41013681)
Evidence

Posterior capsular repair lowers early dislocation

Level III (comparative cohort)
White RE, Forness TJ, Allman JK, Junick DW • Clinical Orthopaedics and Related Research (2001)
Key Findings:
  • Capsulectomy group: 52 of 1,078 hips dislocated within 6 months (4.8%).
  • Formal posterior capsular and short-rotator repair group: 3 of 437 hips (0.7%).
  • The reduction in early dislocation was statistically significant.
  • The main repair-group complication was greater trochanteric avulsion (0.9%).
Clinical implication: Formal posterior soft-tissue repair, not the skin incision, is what makes the modern posterior approach low-dislocation - it is part of the approach, not an afterthought.
Verify on PubMed (PMID 11764346)
Evidence

Side-to-side capsular repair technique and dislocation

Level III (single-surgeon comparative cohort)
Hernandez NM, Steele JR, Wu CJ, et al. • Arthroplasty Today (2020)
Key Findings:
  • 841 posterior-approach THAs by one surgeon (605 transosseous-to-trochanter repair, 236 side-to-side soft-tissue repair).
  • All 22 dislocations occurred in the transosseous group; zero in the side-to-side repair group.
  • Increasing age independently raised dislocation odds (OR 1.04 per year).
  • Repair technique, not just the fact of repair, influenced stability.
Clinical implication: How the posterior capsule is repaired matters - a robust side-to-side construct can further reduce early dislocation.
Verify on PubMed (PMID 32995415)
Evidence

LFCN lesions after the direct anterior approach

Level IV (systematic review of Level II-IV studies)
Dahm F, Aichmair A, Dominkus M, Hofstaetter JG • Orthopaedics & Traumatology, Surgery & Research (2021)
Key Findings:
  • 45 studies reviewed; reported LFCN lesion rates ranged from 0 to 83%.
  • Studies primarily focused on the LFCN reported a mean rate of 31%, versus 3.8% when the nerve was not the focus.
  • There is no uniform definition of a postoperative LFCN lesion.
  • Reported incidence has risen over time as awareness increased.
Clinical implication: LFCN disturbance is frequent and historically under-reported - consent specifically for it and protect the interval near the ASIS rather than dissecting blindly in subcutaneous tissue.
Verify on PubMed (PMID 33962046)
Evidence

Direct anterior versus posterolateral - randomized evidence

Level II (meta-analysis of RCTs)
Yang XT, Huang HF, Sun L, et al. • Orthopaedic Surgery (2020)
Key Findings:
  • Pooled RCTs: 932 patients (467 direct anterior, 465 posterior).
  • LFCN injury was far more common with direct anterior (RR 38.97).
  • Direct anterior gave less early pain and earlier discontinuation of walking aids.
  • Operative time, hospital stay and intraoperative blood loss did not differ.
Clinical implication: Even in randomized data the LFCN signal is striking - the early-mobilisation benefit of direct anterior is real but must be weighed against nerve symptoms.
Verify on PubMed (PMID 32558261)
Evidence

Ilioinguinal versus modified Stoppa for acetabular ORIF

Level III (meta-analysis, 3 RCTs and 7 retrospective studies)
Srivastava A, Rajnish RK, Kumar P, Haq RU, Dhammi IK • Archives of Orthopaedic and Trauma Surgery (2022)
Key Findings:
  • 10 studies, 717 patients.
  • Modified Stoppa: shorter surgery, less blood loss, fewer overall complications (OR 2.14) and lower infection (OR 2.17).
  • Ilioinguinal gave better radiographic reduction quality (OR 0.59 favouring ilioinguinal).
  • Vascular injury, nerve injury, heterotopic ossification and clinical outcome were equivalent.
Clinical implication: Modified Stoppa is faster and lower-morbidity, while ilioinguinal may give marginally better reduction - choose by fracture pattern and team familiarity, not dogma.
Verify on PubMed (PMID 35138428)
Evidence

Updated Stoppa versus ilioinguinal synthesis

Level III (updated systematic review and meta-analysis)
Shigemura T, Murata Y, Yamamoto Y, et al. • Orthopaedics & Traumatology, Surgery & Research (2022)
Key Findings:
  • 6 studies pooled.
  • Modified Stoppa achieved a higher anatomical reduction rate (OR 1.75), shorter operative time and lower blood loss.
  • Nerve injury, vascular injury, infection and heterotopic ossification rates did not differ.
  • Excellent or good clinical scores were comparable between approaches.
Clinical implication: A second independent synthesis supports modified Stoppa for efficiency and reduction quality in anterior-column and quadrilateral-surface patterns.
Verify on PubMed (PMID 35066214)
Evidence

Contemporary epidemiology and outcomes of acetabular fractures

Level III (meta-analysis, 8,389 fractures)
Kelly J, Ladurner A, Rickman M • Injury (2020)
Key Findings:
  • Mean patient age rose from 38.6 to 45.2 years over two decades.
  • Anterior-column-based patterns have increased; the anterior intrapelvic approach has become relatively common.
  • Iatrogenic nerve injury, particularly sciatic, has fallen substantially.
  • Post-traumatic osteoarthritis (Matta grade III/IV in 16.9%) remains the dominant complication.
Clinical implication: The acetabular fracture population is ageing toward anterior patterns - hence the rise of intrapelvic exposure - but reduction quality still drives long-term arthritis risk.
Verify on PubMed (PMID 32646650)
Evidence

Safe surgical dislocation of the hip (Ganz)

Level IV (landmark technique and prospective case series)
Ganz R, Gill TJ, Gautier E, Ganz K, Krugel N, Berlemann U • Journal of Bone and Joint Surgery (British) (2001)
Key Findings:
  • 213 hips over 7 years using a trochanteric flip osteotomy through a posterior approach.
  • The external rotators are not divided so the medial femoral circumflex artery is protected by an intact obturator externus.
  • Femoral head perfusion was verified intraoperatively; no case developed avascular necrosis.
  • Morbidity was low and the technique gives circumferential access to head and acetabulum.
Clinical implication: Surgical hip dislocation is safe only because of medial femoral circumflex protection - the deep branch must never be jeopardised when releasing the short rotators.
Verify on PubMed (PMID 11764423)
Evidence

The Bernese periacetabular osteotomy (Ganz)

Level IV (landmark technique and preliminary results)
Ganz R, Klaue K, Vinh TS, Mast JW • Clinical Orthopaedics and Related Research (1988)
Key Findings:
  • Reorientation osteotomy performed through a single Smith-Petersen approach.
  • The acetabular fragment can be tilted around all three axes and medialised while the posterior column stays mechanically intact.
  • Stability is achieved by simple screw fixation, allowing early mobilisation without a cast.
  • Reported complications included intra-articular extension, transient femoral neuropraxia, nonunion and heterotopic ossification.
Clinical implication: The Bernese PAO remains the reference acetabular reorientation for symptomatic dysplasia in the skeletally mature hip; abductors, femoral nerve, vessels and joint blood supply must all be respected.
Verify on PubMed (PMID 3383491)
Evidence

Corona mortis - cadaveric prevalence in the intrapelvic approach

Level V (cadaveric anatomical study)
Sambhav K, Nayyar AK, Elhence A, Gupta R, Ghatak S • Mymensingh Medical Journal (2022)
Key Findings:
  • 62 hemipelvises (31 cadavers) dissected via the anterior intrapelvic approach.
  • A corona mortis anastomosis was present in 80.6% of hemipelvises.
  • The venous variant (40.3%) was more common than the arterial variant (16.1%).
  • Venous bleeding behind the superior pubic ramus is harder to control than arterial.
Clinical implication: Expect a corona mortis in most pelves during intrapelvic work; identify, clip or ligate it deliberately rather than sweeping blindly over the superior pubic ramus.
Verify on PubMed (PMID 35780370)

Clinical Scenarios

Practise clinical reasoning and management decisions out loud

Viva scenarioChallenging
Posterior wall acetabular fracture
Clinical prompt

“A young adult has a posterior hip dislocation reduced in emergency. CT shows a displaced posterior wall fracture with marginal impaction.”

Viva scenarioAdvanced
Elderly anterior column fracture with medialisation
Clinical prompt

“An older patient has an acetabular fracture with anterior column involvement, quadrilateral surface displacement and medial femoral head migration.”

Viva scenarioStandard
Primary THA approach discussion
Clinical prompt

“A patient asks which approach is best for primary total hip replacement.”

Viva scenarioCritical
Unstable pelvic ring
Clinical prompt

“A patient has an unstable pelvic ring injury with symphyseal diastasis and posterior sacroiliac disruption.”

Controversies & Areas of Uncertainty


These are the live debates an examiner uses to test judgement rather than recall. A safe answer acknowledges genuine equipoise and then states a defensible position.

Is direct anterior the best primary THA approach?
Arguments for
Earlier pain relief, more cups in the Lewinnek zone, lower posterior instability risk
Arguments against
Higher intraoperative fracture and LFCN injury, longer operative time, real learning curve
Pragmatic position
No universal winner; choose the approach you perform safely and counsel approach-specific risks
Modified Stoppa or ilioinguinal for anterior-column fractures?
Arguments for
Stoppa is faster, less blood loss, fewer complications and gives medial quadrilateral access
Arguments against
Ilioinguinal may give marginally better radiographic reduction and more lateral iliac access
Pragmatic position
Pattern-driven choice; many units now default to anterior intrapelvic with a lateral window when needed
Percutaneous versus open posterior pelvic ring fixation
Arguments for
Percutaneous iliosacral or transsacral screws are low-morbidity if reduction and corridors are adequate
Arguments against
Sacral dysmorphism narrows safe corridors; malreduction cannot be corrected through a screw
Pragmatic position
Reduce first; fix percutaneously only with a safe corridor, otherwise open or navigate
Acute total hip replacement versus ORIF in older acetabular fractures
Arguments for
Avoids two operations, allows early weight-bearing, addresses poor bone and head damage
Arguments against
Technically demanding, fixation of columns still required, limited long-term data
Pragmatic position
Reserve for selected elderly patients with comminution, impaction or head injury in experienced hands
Intraoperative navigation and robotics for pelvic screws
Arguments for
May improve screw accuracy and reduce neural breach in difficult corridors
Arguments against
Cost, availability, radiation and workflow time; fluoroscopy in expert hands remains reliable
Pragmatic position
Useful adjunct for dysmorphic sacra and transsacral screws, not a substitute for anatomy knowledge
Open Debates in Hip and Pelvis Approaches
ControversyArguments forArguments againstPragmatic position
Is direct anterior the best primary THA approach?Earlier pain relief, more cups in the Lewinnek zone, lower posterior instability riskHigher intraoperative fracture and LFCN injury, longer operative time, real learning curveNo universal winner; choose the approach you perform safely and counsel approach-specific risks
Modified Stoppa or ilioinguinal for anterior-column fractures?Stoppa is faster, less blood loss, fewer complications and gives medial quadrilateral accessIlioinguinal may give marginally better radiographic reduction and more lateral iliac accessPattern-driven choice; many units now default to anterior intrapelvic with a lateral window when needed
Percutaneous versus open posterior pelvic ring fixationPercutaneous iliosacral or transsacral screws are low-morbidity if reduction and corridors are adequateSacral dysmorphism narrows safe corridors; malreduction cannot be corrected through a screwReduce first; fix percutaneously only with a safe corridor, otherwise open or navigate
Acute total hip replacement versus ORIF in older acetabular fracturesAvoids two operations, allows early weight-bearing, addresses poor bone and head damageTechnically demanding, fixation of columns still required, limited long-term dataReserve for selected elderly patients with comminution, impaction or head injury in experienced hands
Intraoperative navigation and robotics for pelvic screwsMay improve screw accuracy and reduce neural breach in difficult corridorsCost, availability, radiation and workflow time; fluoroscopy in expert hands remains reliableUseful adjunct for dysmorphic sacra and transsacral screws, not a substitute for anatomy knowledge

Differential of a Postoperative Neurological Deficit


A new deficit after a hip or pelvic approach is a clinical emergency of reasoning, not panic. Localise the lesion, decide if it is compressive and reversible, and act.

Foot drop, sensory loss in foot after posterior hip or Kocher-Langenbeck
Most likely cause
Sciatic nerve (peroneal division) traction or compression
Discriminators
Knee flexion eases tension; check for haematoma; review intraoperative retraction
Action
Flex knee, extend hip, release tension; explore or decompress if compressive cause suspected
Quadriceps weakness and anterior thigh numbness after anterior or intrapelvic approach
Most likely cause
Femoral nerve injury or compression
Discriminators
Loss of knee extension and patellar reflex; consider retractor on iliopsoas or haematoma
Action
Imaging for haematoma, decompress if compressive, document and counsel on recovery
Numbness over anterolateral thigh after direct anterior approach
Most likely cause
Lateral femoral cutaneous nerve neuropraxia
Discriminators
Purely sensory, no motor loss; very common and often self-limiting
Action
Reassure, document, expect improvement; persistent dysaesthesia may need referral
Medial thigh sensory change and adductor weakness after intrapelvic or quadrilateral work
Most likely cause
Obturator nerve injury
Discriminators
Adductor weakness with medial thigh numbness
Action
Document, counsel; consider exploration only if a clear intraoperative cause is suspected
Global limb deficit with expanding swelling and rising pain
Most likely cause
Compressive haematoma or vascular injury
Discriminators
Tense swelling, falling haemoglobin, absent or changing pulses
Action
Urgent imaging or return to theatre, involve vascular surgery, do not wait
New Deficit After a Hip or Pelvic Approach
PatternMost likely causeDiscriminatorsAction
Foot drop, sensory loss in foot after posterior hip or Kocher-LangenbeckSciatic nerve (peroneal division) traction or compressionKnee flexion eases tension; check for haematoma; review intraoperative retractionFlex knee, extend hip, release tension; explore or decompress if compressive cause suspected
Quadriceps weakness and anterior thigh numbness after anterior or intrapelvic approachFemoral nerve injury or compressionLoss of knee extension and patellar reflex; consider retractor on iliopsoas or haematomaImaging for haematoma, decompress if compressive, document and counsel on recovery
Numbness over anterolateral thigh after direct anterior approachLateral femoral cutaneous nerve neuropraxiaPurely sensory, no motor loss; very common and often self-limitingReassure, document, expect improvement; persistent dysaesthesia may need referral
Medial thigh sensory change and adductor weakness after intrapelvic or quadrilateral workObturator nerve injuryAdductor weakness with medial thigh numbnessDocument, counsel; consider exploration only if a clear intraoperative cause is suspected
Global limb deficit with expanding swelling and rising painCompressive haematoma or vascular injuryTense swelling, falling haemoglobin, absent or changing pulsesUrgent imaging or return to theatre, involve vascular surgery, do not wait
Reversible causes first

When a new deficit appears, exclude a treatable compressive cause - haematoma, tight closure, malpositioned retractor or a too-tight construct - before attributing the deficit to irreversible intraoperative nerve damage.

Guidelines, Registries & Global Practice


Hip and pelvic approach practice is shaped less by formal disease guidelines than by arthroplasty registries, trauma society principles and local resources. The unifying global principle is that the approach should reach the target safely in that patient and that complex acetabular and pelvic injuries belong in teams with the imaging, reduction tools and supporting specialties to manage them.

Global epidemiology

  • Total hip arthroplasty is among the most common and most successful elective operations worldwide, with very high implant survival reported across major registries.
  • The acetabular fracture population is ageing, with mean age rising from the late 30s toward the mid-40s and a growing proportion of anterior-column patterns and low-energy falls (Kelly et al., Injury 2020).
  • Pelvic ring injuries follow a bimodal pattern: high-energy trauma in younger patients and fragility fractures of the pelvis in older patients, the latter rising with population ageing.

Side-by-side society positions

AAOS (US)
Emphasis
Evidence-based THA management and surgeon-individualised approach selection
Practical signal
No single THA approach is mandated; outcomes depend on execution and selection
BOA / BOAST (UK)
Emphasis
Standards for high-energy pelvic and acetabular trauma and time-critical care pathways
Practical signal
Complex pelvic and acetabular injuries should be managed in or referred to specialist centres
AO Foundation
Emphasis
Reduction-target-led approach selection and column-based acetabular principles
Practical signal
Choose the exposure that controls the displaced column or wall directly
EFORT / European consensus
Emphasis
Cross-national education and outcome benchmarking via registries
Practical signal
Audit approach-specific complications against registry comparators
How Major Bodies Frame Approach-Relevant Practice
BodyEmphasisPractical signal
AAOS (US)Evidence-based THA management and surgeon-individualised approach selectionNo single THA approach is mandated; outcomes depend on execution and selection
BOA / BOAST (UK)Standards for high-energy pelvic and acetabular trauma and time-critical care pathwaysComplex pelvic and acetabular injuries should be managed in or referred to specialist centres
AO FoundationReduction-target-led approach selection and column-based acetabular principlesChoose the exposure that controls the displaced column or wall directly
EFORT / European consensusCross-national education and outcome benchmarking via registriesAudit approach-specific complications against registry comparators

Registry evidence

  • AOANJRR (Australia), NJR (England, Wales, NI and IoM), AJRR (US), SHAR (Sweden), the Norwegian and New Zealand registries collectively report excellent long-term THA survivorship and allow approach, fixation and bearing comparisons at population scale.
  • Registries are the appropriate denominator for approach-specific signals such as dislocation, periprosthetic fracture and early revision; single-surgeon series cannot replace them.

High- versus limited-resource practice variation

  • In well-resourced settings, CT, three-dimensional planning, intraoperative navigation, cell salvage, interventional radiology and dedicated pelvic trauma teams are routinely available.
  • In limited-resource settings, plain radiographs and Judet views, careful clinical reduction, external fixation and damage-control principles carry more weight, and early referral of complex acetabular or pelvic injuries to a capable centre is often the safest decision.
  • The constant across all settings is sound anatomy, a reduction-target-led approach, control of danger structures and a defined bailout.
Exam day cheat sheet
Hip and Pelvis Approach Summary

Describe Any Approach

  • Position and table setup.
  • Landmarks and incision.
  • Internervous or intermuscular interval.
  • Structures at risk.
  • Exposure target and bailout plan.
  • Repair and closure.

Hip Arthroplasty

  • Anterior: LFCN and femoral exposure.
  • Lateral: superior gluteal nerve and abductor repair.
  • Posterior: sciatic nerve and posterior repair.
  • Revision: extensile exposure and implant-removal plan.

Acetabulum

  • Posterior wall or column: Kocher-Langenbeck.
  • Anterior column or wall: ilioinguinal or modified Stoppa.
  • Quadrilateral surface: intrapelvic access.
  • Complex patterns: combined or staged approach.

Do Not Miss

  • Corona mortis in anterior pelvic surgery.
  • Sciatic nerve in posterior acetabular exposure.
  • Abductor repair after lateral hip exposure.
  • Posterior ring instability in pelvic ring injury.

“A safe hip or pelvic approach is chosen by target pathology, planned from imaging, performed through a known interval and closed with repair of the structures that maintain function and stability.”

References

  1. 1
    Wang H, Liu JF, Wang F, et al.. "A comparison of the clinical efficacy of total hip arthroplasty via direct anterior approach and posterior approach: A meta-analysis". Medicine (Baltimore). 2024PubMed
  2. 2
    Liu R, Zhao Y, Yu Z, et al.. "Comparative efficacy of direct anterior approach versus conventional surgical approaches in total hip arthroplasty: a systematic review and meta-analysis of randomized clinical trials". Journal of Orthopaedic Surgery and Research. 2025PubMed
  3. 3
    White RE, Forness TJ, Allman JK, Junick DW. "Effect of posterior capsular repair on early dislocation in primary total hip replacement". Clinical Orthopaedics and Related Research. 2001PubMed
  4. 4
    Hernandez NM, Steele JR, Wu CJ, et al.. "A specific capsular repair technique lowered early dislocations in primary total hip arthroplasty through a posterior approach". Arthroplasty Today. 2020PubMed
  5. 5
    Dahm F, Aichmair A, Dominkus M, Hofstaetter JG. "Incidence of lateral femoral cutaneous nerve lesions after direct anterior approach primary total hip arthroplasty - a literature review". Orthopaedics & Traumatology, Surgery & Research. 2021PubMed
  6. 6
    Yang XT, Huang HF, Sun L, et al.. "Direct anterior approach versus posterolateral approach in total hip arthroplasty: a systematic review and meta-analysis of randomized controlled studies". Orthopaedic Surgery. 2020PubMed
  7. 7
    Srivastava A, Rajnish RK, Kumar P, Haq RU, Dhammi IK. "Ilioinguinal versus modified Stoppa approach for open reduction and internal fixation of displaced acetabular fractures: a systematic review and meta-analysis of 717 patients across ten studies". Archives of Orthopaedic and Trauma Surgery. 2022PubMed
  8. 8
    Shigemura T, Murata Y, Yamamoto Y, et al.. "Comparison between ilioinguinal approach and modified Stoppa approach for the treatment of acetabular fractures: an updated systematic review and meta-analysis". Orthopaedics & Traumatology, Surgery & Research. 2022PubMed
  9. 9
    Kelly J, Ladurner A, Rickman M. "Surgical management of acetabular fractures - a contemporary literature review". Injury. 2020PubMed
  10. 10
    Ganz R, Gill TJ, Gautier E, Ganz K, Krugel N, Berlemann U. "Surgical dislocation of the adult hip: a technique with full access to the femoral head and acetabulum without the risk of avascular necrosis". Journal of Bone and Joint Surgery (British). 2001PubMed
  11. 11
    Ganz R, Klaue K, Vinh TS, Mast JW. "A new periacetabular osteotomy for the treatment of hip dysplasias. Technique and preliminary results". Clinical Orthopaedics and Related Research. 1988PubMed
  12. 12
    Sambhav K, Nayyar AK, Elhence A, Gupta R, Ghatak S. "Anatomical variations of corona mortis in the anterior intrapelvic approach: a cadaveric study". Mymensingh Medical Journal. 2022PubMed
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Educational content is reviewed for source visibility, editorial coherence, and correction readiness.

No individual clinician credential is claimed unless a named person is shown.

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