Periprosthetic acetabular fracture: Definition, Uses, and Clinical Overview

Posted on February 28, 2026 | by drhip

Periprosthetic acetabular fracture Introduction (What it is)

Periprosthetic acetabular fracture means a break in the hip socket bone around a hip replacement cup.
It can happen during hip replacement surgery or after surgery, sometimes after a fall or with weaker bone.
Clinicians use this term when evaluating hip pain, loss of function, or implant instability in a replaced hip.
It is commonly discussed in total hip arthroplasty (THA) follow-up and revision planning.

Why Periprosthetic acetabular fracture used (Purpose / benefits)

Periprosthetic acetabular fracture is not a device or treatment by itself; it is a diagnosis that describes a specific complication involving the acetabulum (the socket portion of the pelvis) near an implanted acetabular component (the “cup”) of a hip replacement.

Using this diagnosis serves several practical purposes in hip care:

It identifies the source of symptoms when a person with a hip replacement develops new pain, difficulty walking, or a change in leg function. A fracture in the socket region can mimic other causes of post-THA pain, such as muscle strain, tendon irritation, or implant loosening.
It guides imaging choices and interpretation. Standard X-rays may show a fracture line or changes in cup position, while CT scans can better define fracture pattern and bone stock (how much supportive bone remains).
It helps clinicians assess implant stability. Management decisions often hinge on whether the acetabular cup is stable or has shifted (migration) relative to the pelvic bone.
It supports a structured plan for care by framing the problem as bone injury plus implant considerations, rather than a “generic” fracture or “generic” painful hip replacement.
It facilitates communication between emergency clinicians, orthopedic surgeons, radiologists, and rehabilitation teams by describing both the location (acetabulum) and the relationship to the implant (periprosthetic).

Indications (When orthopedic clinicians use it)

Orthopedic clinicians consider or diagnose Periprosthetic acetabular fracture in scenarios such as:

New hip or groin pain after total hip replacement, especially after a fall or twist
Sudden difficulty bearing weight or a notable change in walking ability after THA
Apparent change in hip length, hip alignment, or sense that the joint is “not right”
X-ray findings suggesting cup migration, pelvic fracture lines, or new pelvic bone changes near the implant
Intraoperative recognition of a socket fracture during insertion or seating of the acetabular component
Complex revision hip cases with poor bone quality or pre-existing bone loss where fracture risk is higher
Painful hip replacement with suspected loosening where imaging reveals an associated acetabular fracture
High-energy trauma in a person with a hip replacement (e.g., motor vehicle collision)

Contraindications / when it’s NOT ideal

Periprosthetic acetabular fracture describes a condition, so “contraindications” apply more to specific management approaches than to the diagnosis itself. Situations where a given approach may be less suitable include:

Nonoperative (conservative) management may be less suitable when the acetabular cup is clearly unstable, displaced, or migrating on imaging, because ongoing motion can limit fracture healing and compromise fixation.
Primary fixation alone may be less suitable when there is major bone loss, pelvic discontinuity (a separation through the pelvis affecting socket support), or poor remaining bone quality; alternative reconstruction strategies may be considered.
Immediate full revision may be less suitable in some patients with substantial medical risk from long surgery or blood loss; the balance of risks and benefits varies by clinician and case.
Standard implants may be less suitable when anatomy is severely distorted or bone stock is limited; surgeons may consider specialized components, which vary by material and manufacturer.
Certain imaging tests may be less informative if metal artifact obscures details; alternative imaging protocols or modalities may be used depending on local resources.
Aggressive rehabilitation progression may be less suitable when fracture stability or implant stability is uncertain; plans are typically individualized.

How it works (Mechanism / physiology)

Periprosthetic acetabular fracture occurs when the bone of the acetabulum experiences forces that exceed its strength, in the presence of an acetabular implant.

Biomechanical principle

The acetabulum is a ring-like structure within the pelvis that transfers load from the femoral head to the pelvic bones during standing and walking.
A hip replacement cup changes how load is distributed through bone and implant. If bone is weak, stressed, or impacted by trauma, a fracture can develop around the cup.
Stability depends on the relationship between fracture pattern, bone quality, and implant fixation (press-fit or cemented, plus any supplemental screws or augments).

Relevant hip anatomy and structures

Acetabulum: the hip socket formed by pelvic bones; it includes columns and walls that contribute to stability.
Acetabular component (cup): the implant anchored to the socket bone.
Periacetabular bone stock: the remaining pelvic bone supporting the cup.
Pelvic ring / columns: structural pathways that carry load; certain fracture lines can compromise support.
Soft tissues: muscles and tendons influence function and pain but are not the primary injured structure in this diagnosis.

Onset, duration, and reversibility

Onset can be immediate (intraoperative crack or fracture, or acute trauma) or gradual (stress/insufficiency fracture in weakened bone).
The condition is not “reversible” like a medication effect. Instead, outcomes relate to whether the fracture heals, whether the implant remains stable, and whether reconstruction restores durable load transfer.
Healing and recovery timelines vary by clinician and case, and depend on fracture stability, implant stability, bone health, and rehabilitation progression.

Periprosthetic acetabular fracture Procedure overview (How it’s applied)

Periprosthetic acetabular fracture is a diagnosis that can lead to different management pathways. The overview below describes how clinicians generally evaluate and manage it at a high level.

Evaluation / exam – History: onset of pain, fall/trauma, prior hip surgeries, functional changes, systemic symptoms. – Physical exam: gait tolerance, hip range of motion, tenderness, limb alignment, neurovascular status. – Review of prior operative details when available (implant type, fixation method, prior imaging).
Preparation (planning) – Initial imaging review and classification of fracture pattern and implant stability. – Assessment of bone quality and prior bone loss around the cup. – Planning for either monitoring, protective strategies, or surgery depending on stability and displacement.
Intervention / testing – Imaging commonly starts with pelvis and hip X-rays; CT may be used to define fracture anatomy and component position more clearly. – Nonoperative pathway (when appropriate): close observation with activity modification and repeat imaging at intervals. – Operative pathway (when appropriate): may include fixation of acetabular bone, revision of the acetabular component, bone grafting, augments, or specialized reconstruction constructs. The specific technique varies widely by surgeon and case.
Immediate checks – Reassessment of pain, function, and stability. – Post-intervention imaging to confirm implant position and fracture alignment when applicable. – Early monitoring for complications such as dislocation, persistent instability, or wound issues (in surgical cases).
Follow-up – Serial clinical assessments and imaging to monitor healing and implant fixation. – Rehabilitation progression tailored to fracture stability, implant stability, and baseline strength. – Longer-term surveillance of the hip replacement as indicated.

Types / variations

Clinicians describe Periprosthetic acetabular fracture using several practical “types,” often centered on timing and implant stability.

By timing

Intraoperative fractures: identified during hip replacement or revision surgery, sometimes as a crack during cup seating or screw placement.
Postoperative fractures: occur after surgery, often related to trauma (falls) or bone weakening and stress.

By mechanism

Traumatic fractures: follow a clear injury event.
Insufficiency / stress fractures: occur with weaker bone and repetitive loading, sometimes without a single major injury.

By implant stability

Stable cup with fracture: the implant appears well-fixed and not migrating; management may differ from unstable cases.
Unstable cup with fracture: the cup shifts, loosens, or loses support due to fracture pattern or bone loss.

By fracture pattern and bone loss (classification concepts)

Some frameworks categorize fractures by acetabular columns/walls, degree of displacement, and whether there is pelvic discontinuity.
Revision hip planning also considers bone loss patterns around the cup. Names of classification systems vary, and clinicians may use different systems based on training and institutional preference.

By surgical context

After primary THA versus after revision THA, with revision settings often involving more complex bone loss and prior hardware.

Pros and cons

Pros:

Helps pinpoint a serious, specific cause of pain in a person with a hip replacement
Promotes structured assessment of both bone injury and implant stability
Guides appropriate imaging selection (e.g., when CT may add detail beyond X-ray)
Supports clearer communication between care teams (radiology, orthopedics, rehab)
Helps frame treatment goals: restore stability, support healing, preserve function
Encourages consideration of bone quality and implant fixation in long-term planning

Cons:

Can be difficult to detect early on standard imaging, especially with metal artifact
Often requires individualized decision-making rather than a single standard approach
May involve complex surgery in some cases, with longer recovery and higher demands on rehabilitation
Risks include persistent pain, implant loosening, and reoperation in some scenarios
Classification and terminology can be confusing for patients because “fracture” and “loosening” may overlap
Recovery expectations can be uncertain because outcomes vary by clinician and case

Aftercare & longevity

Aftercare following Periprosthetic acetabular fracture depends on whether the fracture is treated nonoperatively or surgically, and whether the acetabular component is stable. Rather than a single “one-size” plan, teams typically emphasize monitoring stability, supporting healing, and rebuilding safe function.

Key factors that can influence outcomes and durability include:

Fracture pattern and displacement: More complex patterns may alter the socket’s load-bearing structure and can require longer monitoring or more complex reconstruction.
Implant stability: A stable cup may allow different recovery strategies than a migrating or loose cup.
Bone quality and bone stock: Osteoporosis, osteolysis (bone loss around implants), and prior revisions can reduce structural support.
Weight-bearing status and progression: Restrictions or progressions are commonly used to protect healing bone and/or fixation; the details vary by clinician and case.
Rehabilitation participation: Restoring hip strength, balance, and gait mechanics can influence function after healing, especially in older adults or after revision surgery.
Comorbidities: Diabetes, smoking status, inflammatory disease, and nutritional factors can affect healing and surgical risk, though the impact varies across individuals.
Implant and reconstruction choices: Durability can differ by construct design and materials, and also by how well the reconstruction matches the remaining anatomy. Performance varies by material and manufacturer.
Follow-up imaging and surveillance: Repeat imaging is often used to confirm stability and healing over time, especially when symptoms change.

Alternatives / comparisons

Periprosthetic acetabular fracture sits within a broader set of diagnoses that can cause pain or instability after hip replacement. Management may also range from monitoring to major reconstruction.

Observation/monitoring vs active intervention

Observation/monitoring may be considered when the fracture is minimally displaced and the cup appears stable. This approach typically relies on repeat clinical checks and imaging.
Surgical intervention may be considered when the cup is unstable, displacement is significant, or bone support is compromised. The goal is usually to restore stable load transfer and reduce ongoing failure risk.

Imaging comparisons (high level)

X-ray is often the first test because it is quick and shows cup position and obvious fractures.
CT can better define fracture lines, bone loss, and component orientation, though metal artifact can still limit detail. Protocols vary by institution.
MRI is less commonly used for detailed acetabular bone assessment around metal implants due to artifact, though special sequences may help evaluate soft tissues in selected situations.

Nonoperative supports vs reconstructive surgery

Protected activity and rehabilitation focus on functional recovery while monitoring healing, when appropriate.
Fixation (stabilizing bone) versus revision (replacing or re-securing the cup) are different surgical concepts; some cases require both. The best-fit approach varies by clinician and case.

Differentiation from other post-THA problems

Aseptic loosening (implant loosening not caused by infection) can look similar to a fracture on symptoms; imaging and clinical context help distinguish them.
Periprosthetic joint infection can also cause pain and implant problems, but it involves infection workup and a different treatment pathway.
Dislocation may coexist with acetabular instability but is a separate event describing the ball coming out of the socket.

Periprosthetic acetabular fracture Common questions (FAQ)

Q: What does Periprosthetic acetabular fracture mean in plain language?
It means the bone of the hip socket has cracked or broken near the cup of a hip replacement. “Periprosthetic” simply means “around the implant.” The key issue is how the fracture affects the support and stability of the cup.

Q: What symptoms can it cause?
Common symptoms include new groin or buttock pain, pain with standing or walking, and reduced ability to bear weight. Some people notice a sudden functional change after a fall, while others develop symptoms more gradually. Symptoms overlap with other causes of painful hip replacement, so imaging is often important.

Q: Is it the same as the hip replacement “loosening”?
Not exactly, but they can be related. A fracture can make a previously stable cup become unstable, and a loose cup can contribute to bone loss that increases fracture risk. Clinicians often evaluate both fracture pattern and implant fixation together.

Q: How is it diagnosed?
Diagnosis typically starts with a clinical history and physical exam, followed by hip and pelvis X-rays. CT may be used to define the fracture pattern and evaluate cup position and bone stock in more detail. In some cases, additional tests are used to assess other causes of pain, depending on the scenario.

Q: Does it always require surgery?
No. Some fractures may be managed without surgery if the cup is stable and the fracture is not significantly displaced, but this depends on imaging findings and clinical factors. Other fractures require surgical stabilization and/or revision to restore support for the implant. The decision varies by clinician and case.

Q: What does recovery usually involve?
Recovery commonly involves a period of activity modification, structured rehabilitation, and follow-up imaging to confirm stability and healing. If surgery is needed, recovery may include healing time for bone and soft tissues as well as gait retraining. Timelines and milestones vary by clinician and case.

Q: Will I be allowed to put weight on the leg?
Weight-bearing plans are often used to protect healing bone or a reconstruction, but they differ based on fracture stability and implant stability. Some situations allow earlier weight bearing, while others require more restrictions. Specific instructions are individualized by the treating team.

Q: When can someone drive or return to work after this diagnosis?
Driving and work timelines depend on pain control, mobility, ability to safely operate pedals, and—when surgery occurs—postoperative restrictions and medication considerations. Job demands matter as well (desk work vs physically demanding work). Clinicians typically base clearance on functional readiness and safety rather than a single fixed timeline.

Q: What is the cost range for evaluation or treatment?
Costs vary widely by region, insurance coverage, imaging needs, and whether hospitalization or surgery is required. Nonoperative monitoring generally differs in cost from revision surgery and inpatient rehabilitation. It can help to ask a clinic or hospital for an itemized estimate based on the expected pathway.

Q: How long do results last after treatment?
If the fracture heals and the cup remains stable (or is successfully reconstructed), the goal is durable function, but longevity depends on bone quality, implant design, activity level, and follow-up care. Some cases do well for many years, while others may need additional procedures later. Durability varies by clinician and case and by material and manufacturer.