Revision hip arthroplasty

1. High-Yield Summary

• Infection Exclusion Imperative: Every failed, loose, or painful total hip arthroplasty (THA) is considered a periprosthetic joint infection (PJI) until proven otherwise. Preoperative workup mandates serologic erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) measurement, followed by guided synovial aspiration for total leukocyte count, neutrophil percentage (%PMN), alpha-defensin immunoassay, and 14-day aerobic and anaerobic cultures prior to revision.
• Failure Etiology Identification: Surgical intervention must address the specific mechanical or biological root cause of failure: aseptic loosening, PJI, prosthetic instability, adverse local tissue reaction (ALTR/trunnionosis), periprosthetic fracture, or component impingement. Revising an implant without correcting the underlying failure mechanism leads directly to early re-revision.
• Anatomical Bone Defect Mapping: Preoperative radiographs and metal artifact reduction sequence CT (MARS-CT) must be categorized using the Paprosky acetabular (Types I, IIA/B/C, IIIA/B, and pelvic discontinuity) and femoral (Types I, II, IIIA/B, and IV) classification systems. Acetabular bone loss guides the selection of porous hemispherical cups, modular porous metal augments, cup-cage constructs, or custom triflange components. Femoral deficiency determines the required length and diameter of distal diaphyseal scratch-fit fixation.
• Extensile Exposure and Osteotomy Principles: Re-entering scarred surgical corridors requires extensile exposure. Surgeons must maintain a low threshold for an Extended Trochanteric Osteotomy (ETO), which facilitates safe atraumatic stem extraction, controlled cement mantle clearance, straight-line coaxial femoral canal access, and preserves abductor-vastus lateralis continuity on a vascularized anterior hinge.
• Biomechanical Restoration: Reconstruction must restore the anatomical hip center of rotation, femoral offset, and leg length while establishing rigid initial stability (diaphyseal scratch-fit contact over at least 4 cm with interfacial micromotion under 40 micrometers) to facilitate biological osseointegration. Dual-mobility articulations and modular offset options should be strategically utilized in patients with abductor deficiency, spinopelvic stiffness, or recurrent instability.

2. Indications

Revision total hip arthroplasty is indicated when mechanical failure, biological degradation, infection, or periprosthetic skeletal disruption compromises joint stability, produces intractable pain, or threatens progressive loss of host pelvic and femoral bone stock.

Absolute Indications

• Symptomatic Aseptic Loosening: Progressive component migration (greater than 2 mm of axial translation or 4 degrees of angular tilt) associated with continuous circumferential radiolucent lines and progressive periprosthetic osteolysis.
• Chronic Periprosthetic Joint Infection: Confirmed deep PJI requiring staged exchange arthroplasty (resection, interim antibiotic spacer, and delayed reimplantation) or highly selected single-stage exchange.
• Recurrent Prosthetic Dislocation: Recurrent instability failing conservative management (closed reduction and brace immobilization) caused by component malorientation, soft-tissue laxity, impingement, or abductor insufficiency.
• Vancouver B2 and B3 Periprosthetic Fractures: Femoral fractures occurring around or immediately distal to the stem with an unstable, loose femoral component and compromised metaphyseal bone stock.
• Catastrophic Implant Failure: Structural fatigue fracture of a femoral stem, metallic shell dissociation, ceramic liner or head fracture, or catastrophic polyethylene wear-through.

Relative Indications

• Progressive Asymptomatic Osteolysis: Expanding osteolytic cavities threatening acetabular column continuity, anterior/posterior wall integrity, or femoral diaphyseal cortices despite minimal clinical symptoms.
• Recurrent Subluxation and Component Malorientation: Symptomatic micro-instability, edge loading, or subluxation secondary to component version or inclination outside the functional spinopelvic safe corridor.
• Adverse Local Tissue Reaction (ALTR) and Trunnionosis: Mechanically assisted crevice corrosion at modular head-neck or neck-stem tapers with progressive soft-tissue pseudotumor formation, abductor necrosis, or elevated serum cobalt and chromium ion concentrations.
• Symptomatic Leg Length Discrepancy or Offset Loss: Severe abductor lever arm deficiency, gait asymmetry, pelvic obliquity, or disabling limp resulting from component malposition or excessive subsidence.

Contraindications

• Active Uncontrolled Systemic Sepsis: Hemodynamic instability, active bacteremia, or severe systemic sepsis; mandates emergency debridement, implant resection, or Girdlestone resection arthroplasty rather than elective reconstruction.
• Prohibitive Medical Comorbidities: Severe decompensated cardiopulmonary disease, end-stage organ failure, or American Society of Anesthesiologists (ASA) class IV or V status carrying unacceptable perioperative mortality risks.
• Non-Ambulatory Minimally Symptomatic Patients: Bedbound or non-ambulatory individuals with advanced dementia and low functional demand whose operative risks outweigh clinical benefits.
• Uncharacterized Active Infection in Planned Single-Stage Revision: Absence of identifiable microbiological organisms, unknown antimicrobial susceptibility profiles, or presence of extensive soft-tissue sinus tracts precluding single-stage exchange.

Clinical Assessment Criteria

3. Preoperative Planning

Preoperative planning for revision hip arthroplasty requires systematic radiographic templating, dynamic spinopelvic assessment, volumetric 3D bone loss quantification, and a definitive step-by-step infection exclusion protocol.

Imaging Review

• Plain Radiographic Series: A complete series includes a low anteroposterior (AP) pelvis centered on the pubic symphysis with hips in 15 degrees internal rotation, a true cross-table lateral of the affected hip, a Lowenstein lateral, and full-length standing AP and lateral radiographs of the entire femur. Full-length femoral views are critical to assess canal diameter, anterior and lateral bowing, previous hardware, cortical defects, and distal cortical thickness.
• Spinopelvic Radiographic Analysis: Standing and relaxed-seated lateral lumbar spine-to-pelvis radiographs are mandatory. Evaluate sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI). Assess spinopelvic mobility: a flexible spine allows the pelvis to tilt posteriorly by approximately 20 degrees when sitting, opening and anteverting the acetabular cup. A rigid or fused spine (spinopelvic stiffness) fails to retrovert, predisposing the hip to anterior impingement and posterior dislocation when sitting, which mandates customized cup placement (higher inclination and anteversion) or a dual-mobility construct.
• Metal Artifact Reduction Sequence CT (MARS-CT): Indicated for 3D quantification of acetabular bone loss, evaluation of anterior and posterior column integrity, identification of occult pelvic discontinuity, and measurement of remaining cylindrical femoral isthmus length. Acetabular defects are classified by Paprosky: Type I (supportive rim, minimal bone loss), Type II (intact columns, distorted rim: IIA superior lysis, IIB superolateral rim defect, IIC medial wall defect), Type III (non-supportive rim with column deficiency: IIIA superior migration > 3 cm with intact columns, IIIB severe column destruction with medial migration), and pelvic discontinuity. Femoral defects are staged by Paprosky: Type I (minimal metaphyseal loss), Type II (metaphyseal loss with intact diaphysis), Type IIIA (metaphyseal damage with > 4 cm of intact isthmus), Type IIIB (< 4 cm of intact isthmus), and Type IV (complete isthmic deficiency).
• MAVRIC and SEMAC MRI: Multi-acquisition variable-resonance image combination (MAVRIC) or slice-encoding for metal artifact correction (SEMAC) MRI is obtained when assessing suspected ALTR, trunnionosis, or abductor tendon tears, visualizing cystic or solid pseudotumors and quantifying abductor muscle fatty atrophy.
• Stepwise Infection Workup: Serum ESR and CRP are evaluated first. If either is elevated or clinical suspicion is high, perform image-guided hip joint aspiration off antibiotics for at least 2 weeks. Synovial fluid is analyzed for total white blood cell count (threshold > 3,000 cells/uL indicates PJI), differential neutrophil count (> 70% to 80% PMN), synovial alpha-defensin immunoassay, leukocyte esterase strip, and aerobic/anaerobic cultures incubated for 14 days to capture indolent organisms such as Cutibacterium acnes.

Equipment Checklist

Specialized Component and Cement Extraction Instrumentation:

• Moreland flexible osteotomes (straight, curved, reverse-bevel, and gouge configurations).
• Universal slaphammer extractors with threaded collets and clamp adaptors for modular and non-modular stems.
• Explant acetabular retrieval system with contour-matched curved blades for bone-conserving shell removal.
• Ultrasonic cement removal system (OSCAR) with specialized probes for mantle fragmentation.
• High-speed pencil burrs, tungsten carbide metal-cutting burrs, and diamond cutting wheels.
• Trephines, hollow mills, and reverse-threaded broken screw extractors.

Revision Implant Systems:

• Modular tapered fluted titanium revision stems (conical and splined geometries with independent proximal body sizing, version control, and distal locking options).
• Extensively porous-coated cylindrical cobalt-chromium stems.
• Highly porous trabecular metal and porous titanium multi-hole hemispherical revision shells.
• Modular porous metal augments, wedges, buttresses, and structural column blocks.
• Reconstruction cup-cage constructs and custom 3D-printed triflange acetabular components (CTAC).
• Modular dual-mobility bearing systems and constrained tripolar acetabular liners.

Fixation Hardware and Biologics:

• 2.0 mm cobalt-chrome and titanium cerclage cables with calibrated mechanical tensioners and crimp sleeves.
• Trochanteric claw plates and cable-plate reconstruction systems.
• 6.5 mm and 4.5 mm trans-acetabular cancellous bone screws and locking screws.
• High-dose antibiotic-impregnated bone cement (vancomycin, tobramycin, or gentamicin).

Examination Under Anesthesia (EUA)

• Passive Arc of Motion: Assess maximum passive hip flexion, extension, abduction, adduction, and internal/external rotation prior to surgical draping.
• Dynamic Stability and Laxity Assessment: Test for anterior and posterior subluxation, soft-tissue shuck, and rotational impingement. Note the exact degrees of flexion and rotation triggering instability.
• Pelvic Obliquity and Fixed Contractures: Differentiate true anatomical limb shortening from functional shortening secondary to pelvic obliquity, fixed adduction, or spinal scoliosis.
• Limb Length Measurement: Establish intraoperative baseline limb length using fixed pelvic reference pins or Steinmann calipers placed into the iliac crest referencing the greater trochanter or patella.
• Abductor Muscle Tone: Palpate the abductor muscle mass to detect gross structural disruption, detachment, or severe flaccidity indicative of chronic neurological injury.

4. Patient Positioning & Setup

Stable, reproducible patient positioning is essential in revision hip arthroplasty to maintain anatomical orientation and allow uninhibited fluoroscopic evaluation and extensile exposure.

• Operating Table and Rigid Support: A radiolucent operating table or rigid pegboard positioner is utilized. Padded anterior pubic ramus positioners and posterior sacral positioners secure the pelvis rigidly in the lateral decubitus position.
• Pelvic Perpendicular Alignment: The pelvis must be oriented strictly perpendicular to the floor. Verify that the anterior superior iliac spine (ASIS) axis is vertical; anterior or posterior pelvic tilt alters the surgeon visual horizon, producing unrecognized errors in acetabular component anteversion and inclination.
• Pressure Point and Nerve Protection: An axillary roll is placed immediately caudal to the dependent axilla to unload the brachial plexus. The dependent peroneal nerve is protected with viscoelastic foam padding over the fibular neck. The dependent lower extremity is flexed at the knee and cushioned. Viscoelastic padding is positioned between the knees and beneath all bony prominences.
• Wide Sterile Draping: The operative field is prepped and draped widely from the costal margin and iliac crest proximally down to the mid-tibia distally. The entire lower limb is draped free in a sterile stocking to allow unrestricted intraoperative manipulation, hip flexion, rotation, and dynamic stability testing.

Safety Check

• Fluoroscopy / C-Arm Positioning Corridors: Prior to sterile incision, bring the C-arm into the surgical field to confirm unobstructed sterile visualization of the true AP pelvis and the entire femoral shaft down to the supracondylar region.
• Blood Management Protocol: Confirm the availability of cross-matched packed red blood cells, activate the intraoperative cell saver autologous blood salvage system, and verify administration of intravenous tranexamic acid (TXA, 1 g given pre-incision and 1 g following fascial closure).
• Extraction Hardware Confirmation: Verify during the surgical timeout that all specialized extraction tools, trial components, back-up revision implants, and cerclage systems are physically present in the operating room.

5. Approach

Surgical exposure in revision total hip arthroplasty requires an extensile corridor that permits safe extraction of implants, thorough debridement of osteolytic cavities, and rigid reconstruction without causing secondary neurovascular injury.

Primary Surgical Corridor

• Extensile Posterolateral (Southern / Moore) Approach: The primary workhorse exposure for revision hip surgery. It provides comprehensive visualization of the posterior column, posterior acetabular rim, ischium, and the entire femoral shaft. Proximal extension curves over the iliac wing, affording retroperitoneal access or iliac plating for discontinuity. Distal extension follows the lateral border of the femur, enabling extended trochanteric osteotomies, cerclage cabling, and distal cortical windowing.
• Direct Lateral (Hardinge / Transgluteal) Alternative: Involves splitting the anterior abductor muscle belly and vastus lateralis as a continuous myofascial sleeve. While providing high anterior stability and low dislocation rates, it is limited distally and risks superior gluteal nerve denervation if split extends greater than 3 to 5 cm proximal to the trochanteric tip. Severe abductor deficiency and persistent Trendelenburg lurch are major risks if the repaired tendon fails to heal.
• Anterolateral (Watson-Jones) Alternative: Follows the interval between the tensor fasciae latae and gluteus medius. Useful for isolated cup revisions, anterior wall reconstruction, or anterior instability, but affords constrained visualization of the posterior column and limited distal femoral extensibility.

Internervous Plane and Anatomical Dissection

• Lack of a True Internervous Plane: The posterolateral approach does not exploit a classic internervous plane. Superficial dissection splits the gluteus maximus along its muscular fibers (innervated by the inferior gluteal nerve). Deep dissection proceeds between the posterior border of the gluteus medius (superior gluteal nerve) and the short external rotators (piriformis, superior gemellus, obturator internus, inferior gemellus, and quadratus femoris; innervated by muscular branches of the sacral plexus).
• Preservation of Abductor-Vastus Continuity: The confluence between the gluteus medius/minimus tendon insertions and the origin of the vastus lateralis at the vastus ridge forms a continuous functional digastric muscle sleeve. This sleeve must be preserved intact, especially when mobilizing an extended trochanteric osteotomy fragment anteriorly.

Neurovascular Danger Zones

• Sciatic Nerve: Positioned immediately posterior to the short external rotators and gemelli-obturator complex. In revision cases, scar tissue, displaced cement mantles, or posterior wall bone fragments can encase or displace the nerve. The peroneal division is highly vulnerable to traction neurapraxia when lengthening a chronically shortened limb by greater than 2 cm. Safe retraction requires direct visual identification, soft-tissue mobilization, and placing blunt retractors subperiosteally directly on the posterior acetabular rim.
• Superior Gluteal Vessels and Nerve: Exit the pelvis through the greater sciatic notch superior to the piriformis. Vulnerable during excessive proximal retraction of the gluteus medius, high iliac wing exposure, or trans-acetabular screw placement exiting the notch.
• Inferior Gluteal Vessels: Exit the pelvis inferior to the piriformis; aggressive splitting of the gluteus maximus or torn muscular branches can retract intrapelvically, producing severe, hard-to-control hemorrhage.
• Femoral Neurovascular Bundle: Lies anterior to the hip capsule, separated only by the iliopsoas tendon. Overly aggressive or blind placement of sharp anterior acetabular retractors over the anterior rim can pierce the iliopsoas and compress or lacerate the femoral artery, vein, or nerve. Retractors must rest directly against subcapsular bone.
• Obturator Neurovascular Bundle: Traverses the obturator foramen inferomedially. Endangered by screws placed through the anteroinferior acetabular quadrant.

Safe trans-acetabular screw placement is governed by the Wasielewski quadrant system, defined by intersecting two perpendicular lines across the acetabulum (a line from the ASIS through the acetabular center to the posterior-inferior border, and a perpendicular line through the center):

6. Technique

The operative technique is executed in four sequential, disciplined steps, emphasizing bone conservation, systematic clearance of interfaces, and rigid mechanical reconstruction.

Step 1: Exposure, Debridement, and Component Extraction

• Incise: Re-open the previous posterolateral skin incision, extending it proximally 5 cm past the trochanter tip toward the posterior superior iliac spine, and distally along the lateral femoral shaft for 15 to 20 cm.
• Mobilize: Incise the fascia lata and split the gluteus maximus in line with its fibers. Mobilize the scarred subgluteal bursa. Palpate and directly visualize the sciatic nerve; gently mobilize it within its investing fat pad without circumferential skeletonization. Partially release the distal insertion of the gluteus maximus tendon on the femur if distal shaft exposure is required.
• Retract: Tag the piriformis and conjoint tendon (gemelli-obturator internus) with heavy non-absorbable sutures and detach them close to their trochanteric insertion, elevating them as a protective soft-tissue sleeve. Perform a complete 360-degree capsulotomy around the femoral neck and acetabular perimeter, releasing contracted capsular scar to allow atraumatic hip dislocation.
• Osteotomize (Extended Trochanteric Osteotomy [ETO]): When the femoral stem is well-fixed, distal cement is present, or the femoral canal is distorted, perform an ETO. First place a prophylactic 2.0 mm cobalt-chrome cerclage cable 1 cm distal to the planned transverse osteotomy level to prevent crack propagation. Using an oscillating saw and pencil burr, create a 10 to 15 cm longitudinal posterolateral corticotomy just anterior to the linea aspera. Create a radiused transverse corticotomy distally using a burr, ensuring rounded corners to eliminate sharp stress risers. Pass flexible osteotomes along the anterior cortex to gently crack and lever the greater trochanter and attached vastus lateralis anteriorly on their intact anterior periosteal and myofascial hinge.
• Extract (Femoral Component): For cemented stems, utilize ultrasonic osteotomes (OSCAR) to longitudinally segment the cement mantle, followed by retrograde extraction using slaphammer adapters. For ingrown porous stems, pass flexible Moreland osteotomes coaxially along the porous interface to release biological bonding without removing host cortical bone.
• Extract (Acetabular Component): Use the Explant extraction system with contour-matched curved blades rotated along the outer shell circumference. The blades divide the porous-bone interface with minimal host bone loss, avoiding catastrophic column fractures caused by manual levering.

Step 2: Acetabular and Femoral Bone Bed Preparation

• Debride: Completely excise all fibrous pseudomembrane, non-viable reactive tissue, and osteolytic debris from both the acetabular cavity and femoral canal. Obtain multiple deep tissue biopsies for microbiological culture (aerobic, anaerobic, fungal, and mycobacterial) and frozen section histopathology (> 5 PMNs per high-power field indicating persistent acute inflammation or infection).
• Ream (Acetabulum): Carefully assess anterior, posterior, and superior column bone stock and wall integrity. Conservatively ream the acetabulum line-to-line with hemispherical reamers oriented coaxially to the anatomical center of rotation (40 degrees inclination, 20 degrees anteversion). Ream only until bleeding subchondral host bone is reached; preserve the dense cortical peripheral rim and avoid aggressive medial reaming that compromises column continuity.
• Ream (Femur): Inspect the exposed femoral canal through the ETO window. Remove all residual distal cement, fibrous plugs, and neocortex down to pristine endosteal bone using drills, curettes, and ultrasonic tips. Using rigid cylindrical and flexible reamers under fluoroscopic guidance, ream the cylindrical diaphyseal isthmus sequentially in 0.5 mm increments. Ensure straight-line coaxial entry to achieve a minimum of 4 cm (ideally 4 to 6 cm, or 2 to 3 cortical canal diameters) of rigid circumferential scratch-fit contact.

Step 3: Trialing, Augment Placement, and Provisional Fixation

• Trial (Modular Augments): In Paprosky IIB and IIIA defects with superior or posterosuperior segmental bone loss, select modular porous metal augments (wedges or buttresses). Position and shape the augment to fill the structural defect, creating a supportive hemispherical buttress for the cup. Secure the augment rigidly to the host ilium using 2 to 3 countersunk 6.5 mm cancellous screws.
• Trial (Acetabular Cup): Insert the trial hemispherical cup against the bleeding host bone and augment surface. Verify that at least 50% direct contact with viable host bone is achieved. Test for rotational and toggle stability with vigorous manual push-pull maneuvers.
• Insert (Femoral Trial Stem): Select the modular tapered fluted stem trial matching the final diaphyseal reamer diameter. Advance the trial stem into the diaphysis, confirming rigid axial and rotational spline engagement at the predetermined depth. Attach the modular proximal trial body, adjusting body height, offset (standard vs. high offset), and version (typically 10 to 15 degrees anteversion) independently.
• Perform (Dynamic Stability and Limb Length Verification): Assemble trial articulation components and reduce the hip. Evaluate dynamic stability through a complete arc of motion: test posterior stability in 90 degrees flexion, 45 degrees internal rotation, and 10 degrees adduction; test anterior stability in full extension with 30 degrees external rotation and adduction; perform the shuck test to confirm soft-tissue tension; verify absence of prosthetic or bony impingement; and confirm limb length and offset restoration against preoperative fixed Steinmann pelvic calipers and contralateral anatomical landmarks.

Step 4: Final Implant Placement and Soft-Tissue Repair

• Impact (Acetabular Shell): Impact the definitive highly porous trabecular metal / porous titanium hemispherical cup in 40 degrees inclination and 20 degrees anteversion. Drive multiple (minimum 3 to 4) 6.5 mm cancellous bone screws exclusively into the safe posterosuperior quadrant of the ilium. If an augment is used, bond the cup to the augment with a thin layer of antibiotic bone cement.
• Cement / Lock (Liner or Dual-Mobility Shell): Cement a cross-linked polyethylene liner or lock a modular dual-mobility shell into the metal acetabular cup with antibiotic-impregnated polymethylmethacrylate (PMMA) or the locking ring mechanism, confirming desired anteversion.
• Impact (Femoral Stem): Impact the definitive fluted tapered titanium distal stem into the prepared diaphysis until its longitudinal splines rigidly engage cortical bone at the exact predetermined trial depth. Verify absence of axial subsidence or rotational toggle.
• Assemble: Secure the modular proximal body to the distal stem using the manufacturer calibrated torque wrench, verifying dialed version. Clean and dry the trunnion taper; impact the definitive femoral head (ceramic or cobalt-chrome).
• Reduce: Reduce the hip joint under direct vision, confirming stable concentric articulation without soft-tissue interposition.
• Reattach (ETO): Reduce the extended trochanteric osteotomy fragment anatomical onto the femoral shaft. Apply 2 to 3 heavy 2.0 mm cobalt-chrome cerclage cables across the osteotomy segment. Sequentially tighten the cables using calibrated tensioners to 40-50 N-m and crimp securely.
• Repair: Anatomically reattach the posterior capsule and short external rotators (piriformis and conjoint tendon) directly to the posterior trochanteric crest through transosseous drill holes. Close the fascia lata, abductor sleeve, subcutaneous fat, and skin in meticulous tension-free layers over closed suction drains.

Critical Move

The single critical move is achieving rigid initial distal femoral stem fixation (a minimum of 4 cm of scratch-fit spline contact in pristine cylindrical diaphysis with axial and rotational micromotion under 40 micrometers) while anatomically re-establishing the true acetabular center of rotation without relying on uncontained structural bone grafts. Once the distal stem splines engage the diaphyseal cortex, repositioning depth or version without full re-extraction is impossible; seating depth and trajectory must be verified before final impaction.

7. Pearls and Pitfalls

Pearls

• Prophylactic Distal Cerclage Cable: Always place a tensioned 2.0 mm cerclage cable 1 cm distal to the planned transverse cut of an ETO prior to creating cortical cuts or reaming. This completely neutralizes hoop stresses generated by conical reamers and broaches, preventing catastrophic longitudinal fracture propagation down the femoral diaphysis.
• Explant System Cup Retrieval: Utilize the Explant retrieval system with contour-matched curved blades to divide the bone-implant interface of well-fixed shells. Rotating the blades line-to-line conserves vital host bone stock and prevents converting contained Paprosky Type II defects into uncontained Type III column disruptions.
• Dual-Mobility Articulation in High-Risk Patients: Utilize dual-mobility bearings when abductor musculature is compromised, in elderly patients with neuromuscular disease, or when preoperative spinopelvic imaging reveals a rigid, non-mobile lumbosacral spine. Dual mobility markedly increases jump distance and head-to-neck ratios, reducing dislocation rates to under 2% to 4% without imparting high torque to the cup-bone interface.
• Coaxial Diaphyseal Reaming Corridor: Maintain strict straight-line coaxial alignment during femoral canal preparation by adequately mobilizing the ETO fragment and soft tissues; eccentric anterior reaming risks catastrophic anterior cortical perforation.

Pitfalls

• Anterosuperior Quadrant Screw Vascular Laceration: Placing trans-acetabular screws across the thin bone of the anterosuperior quadrant risks penetrating the inner pelvic cortex and lacerating the external iliac artery or vein, causing life-threatening retroperitoneal hemorrhage. Rescue: Confine screw fixation strictly to the safe posterosuperior quadrant.
• Eccentric Posterior Column Reaming: Aggressive reaming directed posteriorly erodes the posterior column and alters the anatomical hip center, creating uncontained structural instability. Rescue: Ream line-to-line, preserve peripheral cortical rim, and reconstruct segmental defects with porous metal augments.
• Static Lewinnek Placement in a Stiff Spine: Placing the cup in standard static Lewinnek orientation (40 degrees inclination, 15 degrees anteversion) in a patient with a stiff or fused lumbar spine causes anterior impingement and posterior dislocation when sitting. Rescue: Assess standing and seated spinopelvic radiographs preoperatively and adjust cup orientation or employ a dual-mobility construct.

8. Postoperative Care

Postoperative management balances the protection of osseous reconstructions and soft-tissue repairs with early mobilization to prevent venous thromboembolism and joint stiffness.

Immediate

• Weight-Bearing Status: Touch-down or partial weight-bearing (20 to 30 lbs) is enforced for 6 weeks when an extended trochanteric osteotomy (ETO), structural porous metal augments, or cup-cage reconstructions are utilized. Patients with isolated stable revisions and intact diaphyseal bone stock are permitted full weight-bearing as tolerated immediately.
• Hip Precautions: Posterior hip precautions (avoid flexion past 90 degrees, adduction past midline, and internal rotation) are maintained for 6 to 12 weeks, especially when a posterior approach was used without dual mobility. Precautions may be relaxed earlier in patients with dual-mobility articulations.
• Venous Thromboembolism (VTE) Prophylaxis: Risk-stratified chemoprophylaxis (low-molecular-weight heparin, direct oral anticoagulants, or aspirin 81 mg twice daily) is administered for 35 days postoperatively, accompanied by bilateral intermittent pneumatic compression devices while in bed.
• Hemodynamic and Wound Surveillance: Serial hemoglobin monitoring; reinfusion of salvaged cell saver blood if indicated; closed-incision negative pressure therapy (ciNPWT) maintained for 5 to 7 days in high-risk soft-tissue envelopes.

Rehabilitation Protocol

• Phase I (Weeks 0 to 2: Acute Protection & Early Mobilization): Focus on safe transfers, touch-down weight-bearing with a walker, active-assisted range of motion within precaution limits, and isometric quadriceps, gluteal, and calf pumping exercises.
• Phase II (Weeks 2 to 6: Intermediate Protected Healing): Progressive gait training maintaining 20 to 30 lb partial weight-bearing with crutches or walker; passive-to-active ROM up to 90 degrees flexion; closed kinetic chain exercises; avoid active abductor resistance to protect the ETO.
• Phase III (Weeks 6 to 12: Osseous Consolidation & Weight Progression): Radiographic confirmation of ETO union and implant stability; transition to full weight-bearing as tolerated; advance to single-point cane on contralateral side; initiate active abductor strengthening and stationary cycling with a high seat.
• Phase IV (> 12 Weeks: Functional Recovery & Conditioning): Discontinue assistive devices when non-antalgic gait is established; advance proprioceptive and balance training; transition to low-impact conditioning (swimming, elliptical, walking); avoid high-impact activities indefinitely.

9. Outcome

Modern revision total hip arthroplasty provides substantial pain relief, restores physical function, and corrects complex biomechanical deformities, although long-term survivorship and patient-reported outcomes remain lower than primary THA.

• Patient-Reported Outcome Measures (PROMs): Significant, durable improvements are seen in Harris Hip Score (HHS, typically improving from 45-55 points preoperatively to 78-86 points postoperatively), Oxford Hip Score (OHS), and Hip disability and Osteoarthritis Outcome Score (HOOS). Functional recovery depends heavily on the integrity of the abductor musculature and the extent of host bone loss.
• Femoral Revision Survivorship: Modular tapered fluted titanium stems demonstrate 10- to 15-year survivorship free from aseptic loosening between 85% and 92% across national registries and multi-center cohorts, providing superior proximal bone preservation and lower rates of thigh pain compared to historical cylindrical fully porous-coated cobalt-chromium stems.
• Acetabular Revision Survivorship: Highly porous titanium and porous tantalum hemispherical shells combined with modular porous augments achieve 10- to 15-year survivorship free from mechanical revision between 88% and 94% for Paprosky Types II and IIIA defects. In complex Paprosky IIIB defects and pelvic discontinuity reconstructed with cup-cage or custom triflange constructs, 10-year survivorship free from re-revision ranges between 80% and 88%.
• Cumulative Re-Revision Burden: International joint registry data indicate an overall 10-year cumulative re-revision rate of 12% to 18% following revision THA. Leading indications for secondary re-revision include recurrent instability (25% to 30%), persistent or recurrent periprosthetic infection (20% to 25%), and progressive aseptic loosening or structural failure (15% to 20%).

10. Complications

Revision hip arthroplasty carries a significantly higher complication profile than primary procedures, driven by distorted tissue planes, altered vascularity, severe bone loss, and extensive operative times.

11. Evidence-Based Synthesis

Modern clinical decision-making is grounded in high-quality randomized controlled trials and prospective registry analyses, corroborated by seminal biomechanical and anatomical descriptions.

12. References

• Ekhtiari S, Gormley J, Axelrod DE et al. Total Hip Arthroplasty Versus Hemiarthroplasty for Displaced Femoral Neck Fracture: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Bone Joint Surg Am. 2020. doi:10.2106/JBJS.20.00226 [Level I: Systematic Review / Meta-Analysis]
• Longo UG, De Salvatore S, Bandini B et al. Debridement, antibiotics, and implant retention (DAIR) for the early prosthetic joint infection of total knee and hip arthroplasties: a systematic review. J ISAKOS. 2024. doi:10.1016/j.jisako.2023.09.003 [Level I: Systematic Review / Meta-Analysis]
• Pentland V, Thompson Z, Dayimu A et al. Survivorship of modern total hip replacement to 30 years: systematic review, meta-analysis, and extrapolation of global joint registry data. Lancet. 2026. doi:10.1016/S0140-6736(25)02305-0 [Level I: Systematic Review / Meta-Analysis]
• Steven Michael Kurtz, Kevin L. Ong, Edmund Lau et al. Projections of Primary and Revision Hip and Knee Arthroplasty in the United States from 2005 to 2030. Journal of Bone and Joint Surgery. 2007. doi:10.2106/jbjs.f.00222 [Level V (Expert Conceptual Review): Seminal Conceptual / Observational Study]
• William Hamilton Harris. Traumatic Arthritis of the Hip after Dislocation and Acetabular Fractures. Journal of Bone and Joint Surgery. 1969. doi:10.2106/00004623-196951040-00012 [Level V (Expert Conceptual Review): Seminal Conceptual / Observational Study]

13. Master Class Pro-Tip

When reconstructing massive acetabular column defects with modular porous metal augments, always remember that augments are structural supports for the cup, not replacements for biological rim contact. Achieve at least 50% direct contact between the final porous cup and viable host bleeding pelvic bone. If using an extended trochanteric osteotomy, place a prophylactic cerclage cable 1 cm distal to the planned transverse osteotomy before initiating cortical saw cuts or burring; this completely neutralizes hoop-stress propagation down the diaphysis during subsequent retrograde stem extraction and modular reaming.

Master Class Surgical Pearl: Revision Total Hip Arthroplasty