Trochanteric Osteotomy Approaches to the Hip (Standard, Extended, Slide)

Why an Osteotomy of the Greater Trochanter?

The greater trochanter is the lateral attachment of the abductor mechanism (gluteus medius and minimus) and the vastus lateralis. Osteotomising it converts the abductor mass into a mobilisable flap that can be reflected proximally or anteriorly, converting a narrow deep wound into a wide exposure of the femoral head and neck, the acetabulum, and the proximal femoral diaphysis. The price of that exposure is that the trochanter must then be securely reattached; if it does not unite and migrates proximally, the abductor lever arm shortens and the hip becomes painful, weak, and unstable. Trochanteric osteotomy was once the default exposure for primary total hip arthroplasty (Charnley low-friction arthroplasty). Modern primary stems and bearings rarely need it, and the standard osteotomy has largely been abandoned for routine primary replacement because of its nonunion and hardware complications. The technique now earns its place in complex primary and especially revision arthroplasty, where exposure is genuinely difficult. Primary Indications: - Complex primary THA requiring wide exposure: protrusio acetabuli, ankylosed or fused hip, stiff ("concrete") hip after prior surgery, high congenital dislocation (Crowe III/IV), severe obesity with deep soft tissue envelope

• Revision THA to extract a well-fixed cemented or uncemented femoral component, or to remove distal cement, a cement restrictor, or a broken stem (extended trochanteric osteotomy)
• Acetabular reconstruction requiring superior access: segmental acetabular grafting, custom or trabecular-metal acetabular components, pelvic discontinuity with antiprotrusio cage
• Femoral deformity (prior malunion, osteotomy) that must be corrected to seat a revision stem
• Tumour resection of the proximal femur where a controlled cortical window preserves abductor attachment Contraindications: - Poor bone stock of the trochanter (severe osteoporosis, prior comminution) that will not hold fixation — the fragment will fragment or migrate
• Active deep infection around the trochanter (relative — reconsider strategy)
• High anaesthetic risk for the lateral decubitus position with prolonged revision time
• Non-compliant patient unable to protect abductors postoperatively (relative)
• A routine, straightforward primary THA where an osteotomy adds only risk ### Why This Approach is Chosen Direct anterior, anterolateral (Hardinge), and posterior approaches give adequate exposure for most primary arthroplasties without dividing bone. They fail when the femoral component is well fixed, when there is substantial distal cement, when the femur is deformed, or when the joint is fused. In these settings the surgeon cannot deliver the component through a soft-tissue-only exposure, and a controlled osteotomy of the trochanter and proximal lateral femur provides a safe, reproducible window. The principle is identical across the three variants: create a mobile bony flap, do the work, then reattach the flap so that abductor function and lever arm are restored. Alternative Approaches (no osteotomy): - Posterior approach — the workhorse for primary and many revisions; excellent acetabular and proximal femoral access, but limited for a well-fixed long stem
• Anterolateral / direct lateral (Hardinge) — splits the abductors in their tendon, good for primary and simple revisions, risks superior gluteal nerve and residual limp
• Direct anterior approach — muscle-sparing internervous plane; limited extension distally and a steep learning curve; not for complex revision
• Extended iliofemoral / transtrochanteric for tumour — much wider, used for proximal femoral resection ### Position & Landmarks Position: Lateral Decubitus, Affected Side Up (Standard) Pre-positioning checklist: - Confirm general or regional anaesthesia and haemodynamic fitness for a potentially long revision
• Beanbag or hip positioner with anterior and posterior pelvic posts at the level of the sacrum and pubis — secure the pelvis so it does not roll during femoral preparation
• Free arm supported on a well-padded armrest
• Axillary roll beneath the dependent axilla to protect the brachial plexus
• All bony prominences padded: dependent greater trochanter, fibular head, lateral malleolus, ankles
• Check and recheck that the pelvis is square — a rolled pelvis distorts cup version and is the commonest cause of malposition A posterior pelvic support at the sacrum and an anterior support at the pubis/ASIS locks the pelvis. The operative leg is draped free so it can be flexed, rotated, and manipulated to deliver the femur. Supine is used when the osteotomy is combined with an anterior or anterolateral exposure; prone is almost never used for hip arthroplasty.

Surface Anatomy and Landmarks: - Greater trochanter — the centrepiece landmark; the incision is centred over it

• Anterior superior iliac spine (ASIS) — anterior reference for femoral neck anteversion and incision angle
• Iliac crest — proximal extension reference
• Femoral shaft — palpable along the lateral thigh; guides the distal limb of the incision and the line of the extended osteotomy
• Gluteus maximus bulk posteriorly (posterior border of the approach) and tensor fascia lata / iliotibial tract anteriorly (split in line with the femur)
• Vastus lateralis ridge (linea aspera origin) — the distal osteotomy limit A straight lateral or posterolateral curved incision centred on the greater trochanter is used. The proximal limb extends 5 to 8 cm above the trochanter tip toward the iliac crest; the distal limb extends along the line of the femur for the length of the planned exposure — critically, for an extended trochanteric osteotomy the distal limb must be long enough to expose the full intended cortical window (often 15 cm or more). Mark the trochanter, the femoral shaft axis, and the planned osteotomy extent on the skin before incision.

The trochanteric osteotomy approaches all share one idea: rather than splitting muscle, divide the bone to which the abductors and vastus lateralis both attach, then mobilise the fragment with whichever soft-tissue sleeve the surgeon chooses to preserve. The three variants differ only in how much lateral cortex is included and whether the abductors and vastus lateralis are left in continuity.

Anatomy

Bony anatomy. The greater trochanter is the lateral prominence of the proximal femur at the junction of the neck and shaft. It carries the insertions of the abductors anteriorly and superiorly (gluteus minimus on the anterior facet, gluteus medius on the superolateral and posterosuperior facets) and the vastus lateralis inferiorly and laterally (along its distal border and the lateral femur). The deep trochanteric fossa, on the medial surface, receives the short external rotators (piriformis, obturator internus with the gemelli, and obturator externus). The trochanter therefore sits at the centre of a continuous muscular cuff: abductors above, vastus lateralis below, short external rotators medially. Functional point: the trochanter projects lateral to the hip centre and so lengthens the abductor moment arm. Detaching it, or letting it migrate proximally, shortens that arm, increasing the force the abductors must generate and producing abductor insufficiency.

Internervous Plane

The true internervous plane exploited by the lateral approach to the hip is between the abductors — gluteus medius and minimus (superior gluteal nerve) above and anterior, and the vastus lateralis (femoral nerve) below and distal. The trochanteric osteotomy develops this interval in the most direct way possible: rather than splitting muscle, it divides the bone to which both groups attach and mobilises the fragment with whichever soft-tissue sleeve the surgeon chooses to preserve.

Common Exposure to the Trochanter

The three variants share a common exposure up to the trochanter. The surgeon then chooses how to divide the bone and how much of the soft-tissue sleeve to preserve.

The Three Osteotomy Variants

With the trochanter exposed, the variant is chosen. Each is simply a statement about how much of the lateral cortex is included and whether the abductors and vastus lateralis are left in continuity.

Standard Trochanteric Osteotomy

Concept: the greater trochanter is osteotomised as a single piece, detaching it with the gluteus medius and minimus so the whole abductor mass can be reflected proximally and the hip widely exposed. Technique: 1. After the lateral exposure and haemostasis of the ascending branch of the lateral femoral circumflex artery, clear the trochanteric bursa and define the anterior and posterior borders of the trochanter. 2. Pass a retractor from distal-anterior to proximal-posterior, deep to the gluteus minimus and on the femoral neck, to protect it and to deliver the trochanter. 3. Make the osteotomy with an oscillating saw or a Gigli saw passed under the abductors, beginning just distal to the vastus tubercle on the lateral cortex and aiming proximally and medially toward the trochanteric fossa. The cut should leave a fragment large enough to hold fixation and should carry a thin shelf of lateral cortex for reattachment. 4. The trochanteric fragment, with gluteus medius and minimus attached, is reflected proximally and held with stay sutures. 5. The hip is then dislocated and the joint exposed. Biomechanics: the trochanter is pulled proximally by the abductors, so reattachment is loaded in tension. The fragment bed is prepared (punctate or a small trough) and fixation chosen to convert distracting force into compression where possible. Indications: complex primary THA (protrusio, fused hip, high dislocation), wide acetabular exposure, and selected revisions where the stem need not be extracted through a cortical window. Problem: because the fragment is detached from the vastus lateralis, the only soft tissue tethering it is the abductor tendon — nonunion and proximal migration are common enough that the standard osteotomy is avoided for routine work. #### Trochanteric Slide (Glassman / Engh) Concept: the osteotomy is made so that the gluteus medius and minimus remain in continuity with the vastus lateralis through the trochanteric fragment. The fragment is not detached and swung free; instead the entire abductor-to-vastus-lateralis sleeve is slid anteriorly off the femur, like opening a curtain, preserving a continuous soft-tissue band from ilium to femur. Technique: 1. The lateral femur is exposed by splitting the iliotibial tract and elevating the vastus lateralis from the lateral intermuscular septum, staying close to bone. 2. The osteotomy begins distally on the lateral cortex at the upper border of the vastus lateralis origin and curves proximally up the anterior aspect of the trochanter, exiting above the abductor insertion. The cut leaves the trochanteric fragment attached above to the gluteus medius/minimus and below to the vastus lateralis. 3. The whole sleeve (abductors — fragment — vastus lateralis) is hinged and slid anteriorly, exposing the anterior capsule and femoral neck without detaching any muscle from the fragment. Why it works: continuous soft-tissue attachment balances the abductors (pulling up) against the vastus lateralis (pulling down and stabilising). The fragment is therefore far less likely to migrate proximally, and its blood supply — supplied through the preserved muscle attachments and the ascending branch of the lateral femoral circumflex artery — is better maintained. Union rates are markedly better than the standard osteotomy. Indications: most revision work that needs anterior femoral exposure but not a long cortical window; preferred where the surgeon wants trochanteric mobilisation with low migration risk. #### Extended Trochanteric Osteotomy (Younger / Paprosky) Concept: a long longitudinal osteotomy of the lateral proximal femoral cortex that includes the greater trochanter and a distal extension of diaphyseal cortex, creating an elongated cortical fragment (typically 10 to 15 cm, sometimes longer) which is hinged open posteriorly on its soft-tissue attachment. It is the workhorse exposure for removing a well-fixed femoral component or distal cement. Technique: 1. Preoperatively, templating defines the length of the osteotomy — it must extend distal to the tip of the well-fixed stem and any cement plug, and the planned revision stem must gain distal fixation beyond the distal osteotomy cut (a rule of thumb is at least 4 to 6 cm of diaphyseal scratch-fit, or a fluted tapered stem spanning beyond). 2. With the lateral femur exposed, mark two longitudinal cuts on the anterolateral cortex: one along the linea aspera posteriorly and one anteriorly, joined by a transverse distal cut. This outlines a rectangular cortical fragment roughly one-third of the femoral circumference. 3. Cut the longitudinal lines with an oscillating saw or high-speed burr; complete the distal transverse cut. Leave the posterior soft-tissue hinge intact so the fragment opens like the cover of a book, hinging posteriorly. 4. With the fragment hinged open, the femoral component is exposed, divided if long, and extracted; distal cement and restrictors are removed under direct vision with ultrasonic cement extractors, reamers, or retrograde tools. 5. The canal is prepared, the revision stem inserted with distal fixation, and the cortical fragment closed back around it and reattached with cables. Biomechanics: because the fragment is a long diaphyseal strut reattached with cerclage cables around the stem, it contributes to rotational stability of the revision construct and restores the lateral cortical tube. The soft-tissue hinge preserves fragment blood supply and is the reason union is reliable. Indications: removal of a well-fixed cemented or uncemented stem, retained distal cement or cement restrictor, broken stem extraction, femoral deformity correction, and any revision where diaphyseal access is needed.

Structures at Risk

Extensile Options

Proximal extension: the standard osteotomy and slide can be extended proximally by reflecting more of the abductor origin from the ilium, gaining access to the acetabular columns and the outer table of the ilium for complex acetabular reconstruction, grafting, or component impaction. The Ollier or extended iliofemoral approaches are used when true pelvic (column) access is required for tumour or major acetabular reconstruction. Distal extension: the lateral incision extends distally in line with the femur for as far as needed. An extended trochanteric osteotomy is, by definition, the distal extension of the trochanteric principle — the lateral cortical window is lengthened to reach distal cement, a broken stem, or diaphyseal deformity. For very distal work, the lateral approach continues onto the femoral diaphysis with a sub-vastus lateralis elevation. ### Reattachment & Fixation The reattachment step decides whether the abductors will work. The fragment must be held under the abductors' pull long enough to unite, with the trochanter replaced in a position that restores the lever arm.

Reattachment biomechanics — three principles: 1. Restore the lever arm. The trochanter must sit lateral to the hip centre at the correct height. If the abductors are lax after a long-stem revision or lengthening, advance the trochanter distally to retension them. 2. Convert tension to compression where possible. A tension-band construct (fragment, fixation, and a stable distal cortical bridge) lets the abductors' pull compress the fragment to its bed rather than distract it. 3. Match fixation to bone quality. Strong bone holds wires; osteoporotic bone cuts through wires and is better served by a claw/stabilisation plate that distributes load. Technical pearls: - Position the limb in abduction before final tightening to relax the abductors and bring the fragment down to its bed.

• Freshen the fragment bed to bleeding bone; consider a small trough to seat the trochanter.
• Advance the trochanter distally ("trochanteric advancement") if the abductors are lax, to retension them and restore the lever arm — particularly useful after a long stem or leg-lengthening revision.
• Avoid over-tightening wires/cables on osteoporotic bone, which cuts out; consider a claw plate in fragile bone. ### Closure & Aftercare Closure checklist: - Irrigate and achieve haemostasis (ascending branch of lateral femoral circumflex artery, vastus lateralis edges); drain deep to fascia at surgeon preference.
• Secure trochanteric reattachment with the limb held in abduction.
• Repair vastus lateralis to its origin and to the fragment, re-establishing the abductor-vastus lateralis sleeve.
• Close the fascia lata (iliotibial tract) with heavy absorbable suture — the key strength layer.
• Close subcutaneous tissue and skin in layers.
• Obtain AP and lateral radiographs to document fragment position, fixation, stem position, and leg length.
• Document a complete pre- and post-operative neurovascular examination, including sciatic and femoral nerve function and abductor status. Aftercare: - Immediate (0 to 48 hours): neurovascular observations (foot dorsiflexion and plantarflexion, abductor status vs baseline); elevate and ice; multimodal analgesia; VTE prophylaxis per protocol.
• Weight bearing: standard osteotomy with wire fixation — protected (touch to partial) weight bearing for 6 to 12 weeks, then progress as union is confirmed radiographically; slide or extended osteotomy with stable cable fixation may progress more rapidly at surgeon discretion, but avoid active resisted abduction for 6 to 12 weeks; an abduction brace is used if fixation is insecure or the patient is unreliable.
• Follow-up imaging: 2 weeks wound check; 6 and 12 weeks radiographs for fragment position and early union; 6 and 12 months to confirm union and document trochanteric position relative to the centre of rotation. ### Complications

• Complex primary THA — protrusio acetabuli, fused/ankylosed hip, high congenital dislocation (Crowe III/IV), severe obesity with a deep soft-tissue envelope.
• Revision THA with extended trochanteric osteotomy — femoral component and cement extraction, acetabular revision with graft or cage, correction of leg length and offset.
• Acetabular reconstruction — segmental grafting, antiprotrusio cage, custom triflange.
• Tumour resection of the proximal femur with endoprosthetic reconstruction.
• Femoral osteotomy correction combined with arthroplasty.

At a Glance The

trochanteric osteotomy approaches mobilise the greater trochanter — and, in the extended variant, a length of lateral femoral cortex — with its attached abductors to gain wide exposure for complex primary and revision hip arthroplasty. Three variants exist. The standard osteotomy detaches the trochanter with the abductors alone and is now reserved for difficult primaries where wide access justifies its nonunion risk. The trochanteric slide keeps the gluteus medius, trochanter, and vastus lateralis in continuity, balancing the abductors against the vastus so the fragment migrates far less and its blood supply is preserved. The extended trochanteric osteotomy (Younger/Paprosky) extends the principle into a 10 to 15 cm longitudinal cortical window hinged posteriorly, the workhorse for removing a well-fixed femoral component or distal cement. The approach is taken in the lateral decubitus position through a lateral incision centred on the trochanter, exploiting the internervous plane between the abductors (superior gluteal nerve) and vastus lateralis (femoral nerve). The superior gluteal nerve is the critical structure at risk — it runs deep to gluteus medius and divides roughly 3 to 5 cm above the trochanter tip, so dissection must stay within the safe distal zone. Reattachment uses wires, cable-grip systems, claw plates, or cables around the stem; the trochanter must be replaced to restore the abductor lever arm, and the limb is held in abduction during fixation. The feared complication is trochanteric escape — nonunion with proximal migration and abductor insufficiency — best prevented by sound fixation and preserved abductor-vastus lateralis continuity. ### MCQ Practice Points

Guidelines, Registries & Global Practice

Trochanteric osteotomy exposures are used worldwide in complex and revision hip arthroplasty, and their principles converge across examination systems. The standard osteotomy, central to Charnley's low-friction arthroplasty, has largely been superseded for routine primary replacement by soft-tissue-sparing approaches, while the slide and the extended trochanteric osteotomy have become standard in revision practice where exposure demands a controlled bony window.

Registry / population evidence: - Major joint registries (NJR, AOANJRR, AJRR, SHAR) confirm that revision burden is dominated by aseptic loosening, infection, instability, and wear — the scenarios in which trochanteric osteotomy exposures earn their place.

• Long-stem revision series with extended osteotomy report reliable union of the cortical fragment when it is hinged on its soft-tissue sleeve and cabled around the stem, with abductor outcomes tied to fragment position and lever-arm restoration. Global practice variation: in high-resource settings, dedicated trochanteric cable-grip systems, claw plates, and modular fluted tapered revision stems are standard. In resource-limited settings the same biomechanical principles (a hinged cortical window, cerclage reattachment, distal fixation) are achieved with heavy cerclage wire and locally available revision stems; the standard osteotomy sometimes persists where modern approaches are less accessible, with correspondingly higher nonunion rates. Consent (globally applicable): discuss trochanteric nonunion and escape (with abductor weakness and possible instability), wire or cable breakage and trochanteric bursitis, heterotopic ossification, sciatic or superior gluteal nerve injury, fracture, infection, and the possible need for further surgery.