Hemiarthroplasty: Definition, Uses, and Clinical Overview

Posted on February 28, 2026 | by drorthopedic

Hemiarthroplasty Introduction (What it is)

Hemiarthroplasty is a surgical procedure that replaces only one side of a joint.
It is a reconstructive orthopedic procedure (a type of arthroplasty).
It is most commonly used in the hip and shoulder, especially after fractures.
The goal is to restore joint function and reduce pain while preserving the opposite joint surface.

Why Hemiarthroplasty is used (Purpose / benefits)

Hemiarthroplasty is used when one articular surface is irreparably damaged, but the opposing surface is relatively intact or can reasonably be preserved. In practical terms, it aims to solve problems of pain, mechanical instability, and loss of function caused by structural joint failure.

Common clinical goals include:

Rapid restoration of a stable joint after certain fractures, particularly when bone quality or fracture pattern makes internal fixation less predictable.
Pain reduction by removing a damaged articular surface and replacing it with a prosthetic component.
Functional improvement (mobility, transfers, basic arm use) by restoring joint congruence and limb length/biomechanics.
Shortening the “time to mobilization” in select fracture settings compared with strategies that require fracture healing before full function can return (details vary by clinician and case).
Preserving bone and anatomy on the non-replaced side of the joint (for example, keeping the acetabulum in hip hemiarthroplasty or the glenoid in shoulder hemiarthroplasty).

Because only one side of the joint is replaced, Hemiarthroplasty is often positioned on the spectrum between internal fixation (preserving the native joint entirely) and total joint arthroplasty (replacing both sides of the articulation).

Indications (When orthopedic clinicians use it)

Typical scenarios include:

Displaced femoral neck fracture in older adults or patients with limited capacity for fracture healing (hip Hemiarthroplasty).
Comminuted proximal humerus fracture where stable reconstruction is not feasible (shoulder Hemiarthroplasty, selected cases).
Femoral head osteonecrosis (avascular necrosis) in carefully selected patients, when acetabular cartilage is relatively preserved (practice varies).
Failed internal fixation of certain fractures (for example, femoral neck) resulting in nonunion, collapse, or persistent pain.
Severe articular surface damage confined predominantly to one side of the joint, where the other side is not yet significantly arthritic (patient selection dependent).
Salvage situations after prior surgery or trauma when partial joint replacement is judged more suitable than reconstruction (varies by clinician and case).

In day-to-day training and practice, the hip and shoulder are the most frequently discussed settings, and the term Hemiarthroplasty is often taught alongside fracture management algorithms and arthroplasty decision-making.

Contraindications / when it is NOT ideal

Hemiarthroplasty may be less suitable when replacing only one side of the joint is unlikely to provide durable pain relief or stable biomechanics.

Common reasons it is not ideal include:

Advanced arthritis on the non-replaced side (for example, significant acetabular cartilage loss in the hip or glenoid wear in the shoulder), where a total arthroplasty may better address pain and function.
Active infection in or around the joint (a general contraindication to placing a prosthesis until infection is addressed).
Severe soft-tissue or neuromuscular imbalance that increases instability risk (for example, certain neurologic conditions), where outcomes may be less predictable.
Poor bone or soft-tissue support that cannot reliably support the implant choice (implant and fixation strategy vary by case).
Young, high-demand patients in some contexts, where long-term wear of the retained articular surface or later conversion surgery is a concern (decision-making is individualized).
Complex joint pathology requiring reconstruction of both sides of the joint surface for predictable pain relief.

When Hemiarthroplasty is considered, clinicians weigh fracture pattern, cartilage status, functional demands, cognitive status (for rehab participation), and surgical risk.

How it works (Mechanism / physiology)

At a high level, Hemiarthroplasty works by replacing the damaged articular surface with a prosthetic component that can articulate against the patient’s retained native cartilage (or a retained/treated surface).

Biomechanical principle

Joints transmit load through congruent surfaces. When one surface is fractured, collapsed, or no longer spherical/smooth, joint contact pressures rise and motion becomes painful and inefficient.
By substituting a prosthetic “ball” or articular segment for the damaged side, the procedure seeks to restore shape, alignment, and smooth motion while maintaining the opposing surface.

Relevant musculoskeletal anatomy

Hip Hemiarthroplasty: replaces the femoral head (and typically the femoral neck segment) with a prosthetic head attached to a femoral stem. The native acetabulum remains.
Shoulder Hemiarthroplasty: replaces the humeral head while retaining the glenoid. Soft tissues (rotator cuff, capsule, tuberosities in fracture) strongly influence stability and function.

Key tissues and concepts often emphasized in teaching:

Articular cartilage: preserved on the non-replaced side; its condition affects pain relief and longevity.
Subchondral bone: supports the retained cartilage surface; damage can accelerate degenerative changes.
Capsule and surrounding muscles: contribute to stability; imbalance can lead to subluxation/dislocation.
Bone-implant interface: fixation may be cemented or uncemented depending on bone quality and implant design.

Time course and durability considerations

Hemiarthroplasty is not “reversible” in the sense that it permanently replaces a native surface, though revision or conversion to total arthroplasty may be possible later. Over time, some patients develop wear or degeneration of the retained joint surface (for example, acetabular cartilage wear after hip Hemiarthroplasty). The pace and clinical importance of this vary by patient, activity, anatomy, and implant factors (varies by material and manufacturer).

Hemiarthroplasty Procedure overview (How it is applied)

The workflow below is a general educational outline; real-world pathways differ by institution and case.

History and physical examination – Mechanism of injury (if traumatic), baseline mobility and function, pain pattern, comorbidities. – Neurovascular exam, limb alignment/length, soft-tissue status. – For shoulder cases: rotator cuff function and tuberosity involvement are important considerations.
Imaging and diagnostics – X-rays are the primary imaging modality for fractures and arthritic patterns. – CT may be used for complex fracture anatomy or preoperative planning (varies by clinician and case). – Basic preoperative medical evaluation and lab testing are performed per surgical protocols.
Preoperative planning and preparation – Selection of implant type (e.g., unipolar vs bipolar head in hip; stem design; cemented vs uncemented). – Planning leg length, offset, and component sizing to restore biomechanics. – Discussion of goals, limitations, and expected rehab course in general terms.
Intervention (surgery) – Surgical approach is chosen based on joint, pathology, and surgeon preference. – Damaged bone and cartilage on the replaced side are removed, and the implant is positioned and fixed. – Soft-tissue balancing and stability checks are performed intraoperatively.
Immediate postoperative checks – Clinical assessment of pain control, neurovascular status, wound condition. – Postoperative imaging may be obtained to confirm component position (practice varies). – Early mobilization and therapy are typically initiated as appropriate for the indication and stability.
Follow-up and rehabilitation – Physical or occupational therapy focuses on gait mechanics (hip), range of motion and function (shoulder), and safe transfers. – Follow-up visits assess wound healing, function, radiographic appearance, and complications. – Activity progression and precautions vary by joint, surgical approach, and patient factors.

Types / variations

Hemiarthroplasty is not a single device; it is a family of procedures with important variations.

By joint

Hip Hemiarthroplasty: most common use in fracture care.
Shoulder Hemiarthroplasty: used in select fracture patterns and some degenerative conditions.
Less common contexts exist across orthopedics, but hip and shoulder dominate most curricula and practice patterns.

By implant articulation (hip)

Unipolar hemiarthroplasty: prosthetic head articulates directly with the native acetabulum.
Bipolar hemiarthroplasty: an additional bearing exists within the prosthetic head, aiming to distribute motion between prosthetic interfaces (clinical advantages vary by case and evidence interpretation).

By fixation method

Cemented stem: bone cement secures the femoral or humeral stem; often considered when bone quality is poor (choice varies).
Uncemented (press-fit) stem: relies on bone ingrowth/ongrowth into implant surfaces; often considered in better bone quality (choice varies).

By clinical context

Acute fracture setting: performed soon after injury to restore stability and mobility.
Elective/salvage setting: performed for osteonecrosis, failed fixation, or sequelae of trauma when partial replacement is judged appropriate.

By associated soft-tissue reconstruction (shoulder)

In proximal humerus fracture, the handling and healing of the tuberosities and rotator cuff attachments can be critical to function, and technique choices vary accordingly.

Pros and cons

Pros:

Preserves the opposing joint surface, which may conserve bone and simplify certain future options.
Often provides reliable immediate structural stability in select fractures.
Can reduce pain by removing the damaged articular surface.
Typically involves less resurfacing than total joint arthroplasty (one side only).
May be a practical option when cartilage damage is predominantly unilateral.
Implant selection allows tailoring (cemented vs uncemented; head type), depending on anatomy and bone quality.

Cons:

The retained native surface can develop progressive cartilage wear (e.g., acetabular wear after hip Hemiarthroplasty).
Pain relief may be less predictable when the non-replaced side has unrecognized cartilage disease.
Dislocation or instability can occur, influenced by approach, soft tissues, and patient factors.
Other arthroplasty risks remain: infection, fracture, nerve injury, blood clots, loosening (overall risk varies by patient and case).
Function may be limited by soft-tissue healing (notably in shoulder fracture cases).
Some patients may later need conversion to total arthroplasty if symptoms or wear progress.

Aftercare & longevity

Aftercare and longevity depend on the joint, the indication (fracture vs degenerative), implant design, and patient-specific factors.

Key influences include:

Condition of the retained cartilage surface: the healthier the opposing surface, the more likely it is to remain comfortable over time.
Bone quality and fixation choice: cemented versus uncemented fixation is selected based on multiple factors; stability at the bone-implant interface affects performance.
Soft-tissue function and healing: hip abductors, capsule, and (in the shoulder) the rotator cuff and tuberosities strongly influence stability and strength.
Rehabilitation participation and baseline function: therapy helps restore gait, balance, range of motion, and safe movement patterns; the pace of progress varies by clinician and case.
Medical comorbidities: frailty, neurologic disease, poor nutrition, and other systemic factors can affect recovery and complication risk.
Activity demands: higher repetitive loading may accelerate wear of the retained surface or stress the implant-bone interface.
Implant materials and design: bearing characteristics and stem geometry differ (varies by material and manufacturer).

Longevity is typically discussed in terms of symptom control and function rather than a guaranteed duration. Some patients do well for long periods, while others experience pain or mechanical issues earlier, particularly if the retained surface degenerates or soft-tissue function is compromised.

Alternatives / comparisons

The main alternatives depend on the joint and clinical scenario.

Compared with internal fixation (fracture care)

Internal fixation aims to preserve the native joint by stabilizing the fracture with screws/plates/nails.
It may be preferred when the blood supply and bone quality are favorable and healing is expected to be reliable.
Hemiarthroplasty may be considered when the risk of nonunion, collapse, or fixation failure is higher (varies by clinician and case).

Compared with total joint arthroplasty

Total hip arthroplasty (THA) replaces both the femoral head and acetabulum; total shoulder arthroplasty (TSA) replaces humeral head and resurfaces the glenoid.
Total arthroplasty may offer more predictable pain relief when both sides of the joint are arthritic.
Hemiarthroplasty may be selected to preserve the opposing surface, especially in fracture cases or when the glenoid/acetabulum is relatively preserved.
The trade-offs include differing risks of dislocation, wear patterns, and likelihood of later conversion; these comparisons are nuanced and patient-specific.

Compared with nonoperative management

Nonoperative care (analgesics, activity modification, therapy, supportive devices) may be used when surgery is not appropriate or goals are palliative.
For displaced fractures that disrupt joint mechanics, nonoperative care may lead to persistent pain and loss of function; however, suitability depends on overall health status and patient goals.

Other procedure comparisons (shoulder-specific context)

In certain shoulder conditions, reverse shoulder arthroplasty may be considered when rotator cuff function is poor or tuberosity healing is unlikely (decision-making varies by clinician and case).
Hemiarthroplasty may be less favored when stable, functional cuff-dependent mechanics are not expected.

Hemiarthroplasty Common questions (FAQ)

Q: Is Hemiarthroplasty the same as a total joint replacement?
No. Hemiarthroplasty replaces only one side of a joint, while total joint arthroplasty replaces both articulating surfaces. The choice depends on cartilage condition, fracture pattern, and functional goals.

Q: Which joints most commonly undergo Hemiarthroplasty?
The hip and shoulder are the most commonly discussed and performed examples. Hip Hemiarthroplasty is frequently used for certain femoral neck fractures, and shoulder Hemiarthroplasty is used in selected proximal humerus fractures or specific degenerative conditions.

Q: What kind of anesthesia is typically used?
Hemiarthroplasty is usually performed with general anesthesia or regional anesthesia techniques, depending on the joint, patient factors, and institutional practice. The anesthesia plan is individualized and coordinated between surgical and anesthesia teams.

Q: How painful is recovery after Hemiarthroplasty?
Postoperative pain is expected, particularly in the first days to weeks, and is managed with multimodal strategies. Pain experience varies widely based on the indication (fracture vs elective), baseline pain sensitivity, and rehabilitation progress.

Q: How long does the implant last?
There is no single universal duration. Longevity depends on patient activity, bone quality, soft-tissue function, implant design, and the health of the retained joint surface; outcomes vary by clinician and case.

Q: Can the retained side of the joint wear out after surgery?
Yes. Because the prosthesis articulates against native cartilage (such as the acetabulum in hip Hemiarthroplasty), the retained surface can develop progressive wear in some patients. If symptoms become significant, conversion to a total arthroplasty may be considered.

Q: Will I need physical therapy afterward?
Rehabilitation is commonly part of recovery because it helps restore movement patterns, strength, and functional independence. The specific protocol and restrictions depend on the joint, surgical approach, and stability/soft-tissue healing considerations.

Q: Are there activity or work limitations after Hemiarthroplasty?
Often, yes—especially early on—because tissues need time to heal and patients must relearn safe movement patterns. Longer-term expectations vary by joint and by individual factors such as balance, strength, and job demands.

Q: What are common complications clinicians monitor for?
General arthroplasty-related concerns include infection, dislocation/instability, fracture, neurovascular injury, blood clots, and loosening. The likelihood of specific issues varies by patient, implant, and surgical context.

Q: Will I need follow-up imaging?
Follow-up commonly includes clinical assessment and, in many practices, periodic X-rays to evaluate implant position and surrounding bone. The timing and frequency vary by institution and case.