Total elbow arthroplasty—a historical review

Abstract

Background

This review aims to examine the evolution of total elbow arthroplasty (TEA) implant designs to understand common reasons for failure and optimal strategies to address them. TEA has evolved significantly since its inception, with advancements in biomaterials and implant engineering improving longevity. However, complications such as aseptic loosening, wear-related failure, periprosthetic fracture, infection, and instability remain prevalent. Early TEA designs often mimicked knee replacements and faced high failure rates secondary to poor biomechanics and material limitations. Over time, material improvements, such as titanium alloys and cobalt-chromium components, and refined implant designs have enhanced outcomes.

Results

The review identifies key risk factors for TEA failure, including material degradation, technical errors, patient characteristics, and uneven mechanical stress distribution. Advances in implant materials, such as highly cross-linked polyethylene, have significantly reduced wear rates. Improved surgical techniques and patient selection criteria have also contributed to better outcomes. Despite these advancements, challenges persist, particularly in younger and more active patients who place higher mechanical demands on the implants.

Discussion and Conclusion

Future research should focus on refining implant biomechanics, developing biofilm-resistant materials, and integrating robotic-assisted surgical techniques to further reduce failure rates and improve long-term outcomes. Enhanced patient education on activity modifications and adherence to postoperative guidelines are crucial for the success of TEA.

Total elbow arthroplasty (TEA) is a viable treatment option for patients suffering from elbow dysfunction and pain secondary to a range of conditions.^49,58,80 The primary indications include degenerative joint disease and complex fracture, especially in osteoporotic bone.^54,88 While other procedures like arthroscopy may address minor injuries or remove loose fragments in the joint, TEA offers a more definitive solution for patients with severe arthritis or non-reconstructable fractures. However, relative to other joint arthroplasties, TEA yields inferior outcomes with respect to implant survivorship, rates of aseptic loosening, and need for revision surgery.^1,4,6, 7, 8 The reasons for this disparity are unclear. But in order to optimize patient outcomes, elucidating them is vital. As we seek to improve upon the shortcomings of today, the improvements that have already been made may provide a roadmap for future innovation. As healthcare transitions from fee-for-service models to value-based care, the focus is shifting toward maximizing procedure success and minimizing costly revisions. In contrast to total knee and hip arthroplasty—procedures that significantly improve mobility and quality of life—TEA still has considerable room for advancement. Addressing these challenges requires a deeper understanding of historical failure trends, which can suggest improvements in surgical technique, implant design, and postoperative management. By learning from past shortcomings, we can refine TEA and enhance outcomes for future patients.

Historical perspective of total elbow arthroplasty implants

The origins of elbow arthroplasty can be traced back to 1947, when Mellen and Phalen pioneered partial elbow replacements for patients with severe pain and degenerative disease. Their implants, made of simple acrylic components, replaced either the distal humerus or the proximal ulna. Fixation was achieved using tantalum wire or Vitalium (a cobalt-chromium-molybdenum alloy) screws placed through the prosthesis. While innovative, these early designs lacked long-term durability and failed to replicate the complex biomechanics of the elbow, which depends heavily on dynamic soft tissue constraints for stability throughout the range of motion.²⁹

Beginning in the 1970s, MacAusland et al performed the first total elbow replacement using a simple hinged prosthesis with methylmethacrylate-bone-cement fixation. This constrained cobalt-chromium (CoCr) device aimed to restore elbow biomechanics using an axis pin. However, its design required significant resection of the humerus, which destabilized the surrounding soft tissue. Additionally, the increased constraint relative to the native elbow placed excessive stress on the bone-cement interface, leading to high rates of loosening over time.62, 63, 64^,96

The 1980s and 1990s saw a turning point in TEA technology with advancements in both biomaterials and design. The development of stronger and more wear-resistant alloys for the prosthetic components^45,46 reduced the risk of loosening seen with earlier designs.²³ An even more crucial innovation was the linked prosthesis, which represented a significant departure from the simple hinge design.^61,83,105 Unlike its predecessors, the linked prosthesis incorporated a mobile bearing surface that mimicked the natural gliding motion of the elbow joint. This improved implant stability and allowed for a more natural range of motion.

The evolution of TEA has been shaped by the need to balance stability, range of motion, and long-term durability. Early TEA designs were largely unconstrained, aiming to replicate the natural movement of a healthy elbow.^24,46,79,96 These implants, developed in the 1970s and 1980s, offered the greatest potential for a natural range of motion. They were not, however, without drawbacks. Given their lack of inherent stability, these implants required intact ligamentous function, and their success was limited to patients with a favorable soft tissue envelope.

As surgeons encountered a growing number of patients with significant ligamentous instability, often secondary to rheumatoid arthritis (RA) or trauma, constrained TEA designs emerged to address these challenges.^50,98 These implants, incorporating a post and hinge mechanism, were introduced to provide immediate stability by restricting side-to-side and rotational movement. This made them particularly beneficial for patients with severe ligament damage or bone loss. However, the increased constraint also transferred greater stress to the prosthetic components, accelerating wear and potentially increasing the risk of revision surgery. Despite their limitations, constrained implants played a crucial role in expanding TEA indications to a broader patient population.

Recognizing the need for a middle ground, semi-constrained TEA implants were introduced as a compromise between stability and mobility.^{20,51,51,59,70,84,86} These designs incorporated a gliding mechanism that permitted limited lateral movement while maintaining a stable hinge for flexion and extension. First gaining traction in the late 1980s and 1990s, semi-constrained implants provided improved functional outcomes over constrained TEA, offering a more natural-feeling joint and a wider range of motion. However, they still depended on some degree of soft tissue integrity, making patient selection critical. Table I summarizes the major types of TEA implants, and Table II outlines the key historical developments in TEA implants.

Table I.

Summary of major TEA implant types.

Implant design	10-y survivorship rate	Overall complication rate	Common complications	Key clinical considerations/limitations
Unconstrained	81-86%	Higher than linked	Aseptic loosening, instability, infection	Higher revision risk vs. linked, instability risk, less use in current practice
Constrained	83-85%	High (historically)	Mechanical failure, aseptic loosening, infection	Rarely used, high mechanical stress, increased loosening, largely replaced by semi-constrained
Semi-constrained (linked)	85-92%	16-38%	Aseptic loosening, infection, bushing wear, ulnar neuropathy	Most common design, good pain relief/function, lower instability, bushing wear, risk of loosening
Convertible	79-86%	41% (reoperation), 18% (revision)	Aseptic loosening, infection, ulnar loosening, humeral loosening	Modular design allows conversion, high reoperation rate, technical factors (cement, stem length) impact outcomes

TEA, total elbow arthroplasty.

Table II.

Key historical developments in TEA implants and techniques.

Year introduced	Implant type	Material(s)	Advantages	Disadvantages
1970s	Unlinked (Kudo, Capitellum)	Metal-on-polyethylene	Preserves bone stock, less constraint	Requires intact ligaments, higher instability, higher revision risk
1981	Linked, Semiconstrained (Coonrad-Morrey)	CoCr alloy, polyethylene, anterior flange	Inherent stability, reduced humeral loosening, good long-term survivorship	Higher risk of ulnar nerve injury, mechanical complications, wear
1990s	Linked, Semiconstrained (GSB III, Norway)	CoCr alloy, polyethylene	Improved stress distribution, stable	Polyethylene wear, aseptic loosening
2000s	Convertible/Modular (Latitude)	CoCr alloy, polyethylene	Convertible linkage, anatomic reconstruction, modularity	High reoperation rate, aseptic loosening, technical sensitivity
2000s	Linked, Semiconstrained (Discovery)	CoCr alloy, polyethylene	Promising mid-term survivorship, cemented fixation	Revision risk with dominant arm, wear
2010s	Linked, Semiconstrained (Nexel)	CoCr alloy, highly cross-linked polyethylene	Improved mechanical features, better ROM	High short-term complication rate, humeral loosening

TEA, total elbow arthroplasty; CoCr, cobalt-chromium; ROM, range of motion.

More recently, convertible implants have emerged as a response to the limitations of fixed-design TEA systems.^26,32,97 Unlike traditional implants, convertible designs allow intraoperative adjustment between linked and unlinked configurations, providing surgeons with greater flexibility. This adaptability is particularly valuable in cases where ligament integrity is uncertain preoperatively, allowing for real-time decision-making based on intraoperative findings. However, the mechanical complexity of convertible implants introduces concerns regarding wear and technical demands, making their long-term outcomes an area of ongoing investigation.

The introduction of the Neer classification system for elbow osteoarthritis played a vital role in patient selection. By identifying different types of arthritis and their impact on the surrounding bone, surgeons could now better predict which patients would benefit most from TEA.^10,70,74 The combined effect of improved materials, linked prostheses, and better patient selection led to a significant decrease in failure and revision rates. This era marked a shift from a high-risk procedure with limited success to a more reliable surgical option for well-selected patients.^{18,27,38,60,76,99}

Causes of failure and revision

Risk factors for failure and revision

Failures in TEA have long been attributed to a combination of surgical technique and inherent flaws in implant design. Early reports from the 1970s and 1980s, when TEA was still an emerging procedure, highlighted the frequent occurrence of loosening and instability. Dee and colleagues were among the first to document high failure rates associated with early constrained TEA designs, noting that excessive constraint led to stress concentration at the implant-bone interface, accelerating loosening and failure.¹⁷ Similarly, the Mayo Clinic's experience with early TEA systems in the 1980s underscored that improper component positioning, particularly malalignment of the humeral and ulnar components, could result in instability and excessive wear, leading to premature loosening.⁶⁴ Table III summarizes the common complications following TEA.

Table III.

Summary of common complications following TEA.

Complication	Incidence/failure rate	Common management strategies
Aseptic loosening	12.9–53.8% of revisions; 13–38% overall	Revision surgery, implant exchange, improved cementing technique
Infection	3.2–23% (primary/revision); 4–19% of revisions	Débridement, implant removal, staged revision, antibiotics
Periprosthetic fracture	10.3–12% of revisions; 2–4% overall	ORIF, strut grafting, revision arthroplasty
Instability	4.2%	Revision, soft tissue reconstruction, triceps repair
Implant failure	3–7%	Component exchange, revision arthroplasty
Neurovascular injury	2–9%	Observation, neurolysis, nerve repair

TEA, total elbow arthroplasty; ORIF, open reduction internal fixation.

By the 1990s, long-term follow-up studies began to quantify these issues. Trail et al reported that malpositioned implants had up to a 50% greater likelihood of early failure due to instability.¹⁰¹ Around the same time, concerns over polyethylene wear in semi-constrained and constrained designs emerged, with studies showing that debris from worn components could trigger osteolysis and further compromise implant longevity. The introduction of modern implant materials, such as highly cross-linked polyethylene and improved metal alloys, was a direct response to these findings, aiming to enhance durability and reduce wear-related complications.¹⁰¹

In addition to surgical and mechanical factors, early designs also struggled with structural vulnerabilities. Flaws such as inadequate hinge strength in linked prostheses led to component fractures, with research by Morrey et al highlighting that certain constrained TEA systems exhibited a failure rate exceeding 20% due to these mechanical weaknesses.⁶³ These observations drove further refinements in implant structure, including reinforced hinge mechanisms and modular component designs to improve long-term outcomes.

Aseptic loosening, wear, and polyethylene degradation

Aseptic loosening is the most common mode of TEA failure and results from mechanical stress and osteolysis around the implant.^12,41,78,81 Risk factors include high-demand use of the joint, suboptimal implant design, and inadequate cementation techniques. At the microscopic level, aseptic loosening is driven by a chronic inflammatory response triggered by wear particles from the implant, which leads to macrophage activation and the release of pro-inflammatory cytokines.¹⁵ Progressive bone resorption follows and may result in loss of fixation. Over time, this results in pain, decreased function, and ultimately implant failure. Improper cementation follows a similar cascade, as poor joining of cement within the bone can lead to micromotion, wear particle generation, and early implant instability.⁶⁵ Advances in cementing strategies, such as improved pressurization techniques and the use of antibiotic-laden cement, have been proposed to mitigate these risks and enhance implant longevity. Third body wear represents another mechanism of failure, wherein bone cement or other debris deposits between articulating surfaces and progressively abrades them, leading to polyethylene degradation.³⁰ Strategies to mitigate these issues include the use of highly cross-linked polyethylene, alternative bearing surfaces, and improved implant positioning techniques.

The management of aseptic loosening and implant wear often requires revision surgery, which can be complex due to compromised bone stock and soft tissue envelope.^25,36,41 The choice of revision implant and surgical approach depends on the extent of bone loss and overall integrity of surrounding structures. Damaged polyethylene components may need to be replaced at time of revision, and bone defects may need to be grafted. Modular implant designs and bone grafting techniques have been developed to address these challenges and improve fixation in revision cases. Recent advancements in material science have also led to the development of wear-resistant polyethylene and ceramic-based alternatives that may improve long-term durability.^39,68

Future research is focused on optimizing biomechanics and enhancing implant materials and coatings to minimize wear particle generation and polyethylene degeneration.^75,77

Periprosthetic fractures

Periprosthetic fractures are a significant cause of TEA failure and often occur due to trauma or progressive osteopenia.^8,82,90 These fractures are particularly common in elderly patients with poor bone quality or those who have undergone multiple revision surgeries. The reported incidence of periprosthetic fractures after TEA varies, with some studies indicating a prevalence of approximately 15%.⁸² Fractures occur more frequently on the humeral side than the ulnar side. For instance, Athwal and Morrey reported a 0.65% prevalence of humeral component fractures and a 1.2% prevalence of ulnar component fractures following primary TEA.³

Management depends on fracture pattern, implant stability, and patient-specific factors.^40,92,100 Nondisplaced fractures with stable implants may be treated conservatively with immobilization, while displaced or unstable fractures typically require surgical intervention. Internal fixation using plates and screws, strut grafting, or long-stem revision implants are common strategies to restore stability and function. However, in cases with severe bone loss or implant loosening, complete revision arthroplasty may be necessary. The failure rates for TEA can be significant, with studies indicating that up to 25% of TEAs may require revision surgery within 10 years.³⁴ Outcomes vary depending on patient comorbidities, bone quality, and surgical technique. Comorbidities such as diabetes, RA, and obesity are particularly detrimental to outcomes, as they increase the risk of infection and complications.^44,71 The overall rate of union in revision TEA procedures is approximately 70%, with nonunion and infection being the most common complications.¹¹ Advances in implant technology, including porous-coated stems and biologic augmentation techniques, are being explored to enhance fixation and promote bone healing in this setting.

Implant fractures

Implant fracture is a rare but serious complication of TEA that occurs secondary to metal fatigue, stress concentration, and long-term mechanical loading.^35,104 Constrained and semi-constrained implants are most at risk due to force transmission primarily through the prosthetic components with minimal ancillary absorption by the soft tissue envelope. These implants are at a significantly higher risk, with studies showing that constrained implants have a failure rate of up to 25% within 10 years.⁵³ Implant fractures can occur at various time points postsurgery, but they are most commonly reported within the first 5 to 10 years. The incidence of implant fractures in TEA is relatively high, with some studies indicating rates as high as 29%.^42,43 Improper implant positioning, insufficient bone support, and high-demand use can accelerate the development of microcracks in the metal, eventually leading to implant failure.

In the event of implant fracture, early radiographic evaluation is essential to identify fracture patterns and assess the extent of implant damage.⁹ Contingent on the severity of the failure, surgical options may involve replacing the fractured component, reinforced prosthetic designs, or extensive reconstruction with bone grafting.

Preventing implant fracture requires optimization of implant materials and surgical techniques. Advances in implant materials design, such as titanium alloys and CoCr components, have improved durability. Titanium alloys are known for their excellent biocompatibility, high strength-to-weight ratio, and resistance to corrosion.¹⁰² They are also ductile and tough, which allows them to absorb and distribute stress more effectively, reducing the risk of fracture.⁴⁷ CoCr components, on the other hand, are extremely hard and wear-resistant, making them ideal for joint surfaces that experience high levels of friction. These materials also have a modulus of elasticity closer to that of bone, which helps in reducing stress shielding and promoting better load distribution. Additionally, both materials are less prone to corrosion, which is crucial for the longevity of the implants. Modifications in prosthetic design, including stress distribution enhancements and improved fixation strategies, aim to reduce the risk of fracture. Continued research into biomechanical factors is necessary to develop longer-lasting and more resilient prostheses.

Infection

Prosthetic joint infection (PJI) is a devastating complication following TEA^31,33,48,89 and can result in persistent pain, joint swelling, and compromised function. These infections can be uniquely difficult to eradicate due to the lack of native immune surveillance in the artificial joint and favorable conditions for biofilm formation on orthopedic hardware. Staphylococcus aureus, coagulase-negative staphylococci, and Cutibacterium acnes are the most commonly isolated agents, and infections may present in acute, subacute, or chronic forms.^2,106 The timing of infection is relevant in that different organisms tend to cause infections at different time points. Acute infections, occurring within the first 3 months postsurgery, are often caused by more virulent organisms such as S aureus. Subacute infections, presenting between 3 and 12 months, and chronic infections, occurring after 12 months, are more commonly associated with less virulent organisms such as coagulase-negative staphylococci. Outcomes can vary significantly based on the timing of the infection; acute infections typically require more aggressive treatment and may result in poorer outcomes compared to subacute or chronic infections. Patients who have periprosthetic infection of a primary TEA are at higher risk of reinfection, specifically at a 65% risk of reinfection if management involved irrigation and débridement with implant retention, and 47% if management involved a 2-stage revision.^33,87,91

PJI represents a significant cause for TEA failure, and several strategies have been adopted to prevent it. Perioperative antibiotic prophylaxis, including systemic and local antibiotic-laden cement, has significantly reduced infection rates.¹³ Aseptic surgical protocols, including preoperative skin decontamination and intraoperative laminar airflow, are essential in minimizing contamination.

The introduction of antimicrobial coatings and biofilm-resistant materials presents promising strategies for infection prevention. Early detection and aggressive management of infections, such as débridement and targeted antibiotic therapy, are critical to preventing chronic infections that can compromise implant integrity. Future research into biofilm-targeting therapies may offer further advancements in infection control.

A major consequence of PJI is implant instability.^1,95 Chronic infection induces inflammatory bone resorption and soft tissue compromise, weakening the structural integrity of the joint. These inflammatory markers include IL-1, IL-6, TNF-α, and RANKL.²¹ This process may lead to aseptic loosening, bony and ligamentous compromise, and eventually, mechanical failure. Additionally, recurrent infections can necessitate multiple revision procedures, further stripping bone stock and soft tissue, and thereby diminishing the chances of successful revision.

Management typically involves a staged surgical approach, beginning with source control through débridement and implant removal, followed by antibiotic treatment before reimplantation. Single-stage revision may be an option in select cases with well-contained infections and minimal bone loss. In cases of infected TEA, the use of antibiotic-loaded cement spacers is a common practice. These spacers help maintain joint space and deliver high local concentrations of antibiotics to control infection.¹⁰³ Hinged antibiotic-loaded cement spacers, which allow for some degree of elbow movement, have been shown to improve outcomes by reducing stiffness and scarring.⁵² The use of these spacers is particularly beneficial in 2-stage revision procedures, where the spacer is placed during the first stage and the definitive implant is inserted during the second stage. However, persistent infection or severe bone loss may require alternative solutions such as resection arthroplasty or arthrodesis, with substantial attendant decrement in postoperative functional outcomes.

Preventative strategies include perioperative antibiotic prophylaxis, aseptic technique, and medical optimization, particularly in individuals with diabetes or immunosuppression. Antimicrobial-coated implants and improved biofilm-targeting therapies are areas of active interest with potential to reduce infection rates and improve outcomes following TEA.^13,56 Further research is needed to enhance infection detection methods and develop more effective treatment protocols for PJI in TEA patients.

Instability and dislocation

Instability following TEA is a significant cause of failure of unlinked implants, accounting for approximately 15-20% of all TEA failures, and may occur due to ligamentous insufficiency, component malpositioning, or wear-induced joint laxity.^69,107 If surrounding ligaments are compromised during implantation or due to subsequent wear, the joint may become unstable. Inadequate tensioning of the implant or improper alignment can further exacerbate this issue, leading to recurrent subluxation or dislocation. The key ligaments involved in elbow stability are the medial collateral ligament and the lateral collateral ligament. These ligaments can be compromised during surgery if they are cut or damaged while accessing the joint. Additionally, laxity may increase over time secondary to wear and repetitive stress, or differential ligamentous contracture may occur, in either case producing instability.

Stress shielding occurs when the implant takes on too much of the load that would normally be applied to the bone, leading to bone resorption and weakening around the implant, which can result in loosening over time.⁴⁹ Achieving proper soft tissue balance is crucial, as imbalances can lead to instability or abnormal joint mechanics that accelerate implant wear and dysfunction. Additionally, the quality and quantity of the patient's bone are critical considerations; poor bone density or insufficient bone stock can compromise the fixation of the implant, making it more prone to loosening or fractures, thus requiring revision surgery.

During implantation of unlinked TEA, careful surgical techniques are employed to preserve ligaments whenever possible. However, in some cases, ligament reconstruction or repair may be necessary to ensure joint stability. Unlinked prostheses, which theoretically allow for more natural joint movement, are especially susceptible to instability if the surrounding soft tissue envelope is insufficient, and a careful evaluation preoperatively and intraoperatively are critical to ensure adequate soft tissue supports as in place.

Management of TEA dislocation depends on the underlying cause. In cases where soft tissue integrity is compromised, ligament reconstruction or soft tissue augmentation may be necessary. In cases of malpositioning or excessive wear, component revision is often required, with careful attention to proper alignment and tensioning.⁷ Modular implants may be able to accommodate soft tissue variations and reduce instability risk.

Preventive strategies include appropriate patient selection and postoperative rehabilitation focusing on protecting the joint while maintaining range of motion. Advances in implant design, such as semi-constrained options that balance stability with physiological movement, may help reduce instability rates. While the concept of semi-constrained prostheses has always aimed to balance stability with physiological movement, recent advancements have further refined these designs. Modern semi-constrained implants incorporate improved bearing surfaces, more anatomic stem designs, and enhanced linkage mechanisms. Further research is needed to refine these approaches and improve outcomes for TEA patients experiencing instability and dislocation.

Neurovascular complications

Neurovascular complications are another potential contributor to TEA failure and the need for revision. Ulnar nerve injury is most common, as proximity to the surgical field makes the nerve vulnerable to traction, compression, or direct injury during the procedure.^6,57 Radial nerve injury, though less common, can occur due to improper retraction or unintentional trauma during surgery, leading to wrist drop or decreased function in the hand and forearm.^19,108 The brachial artery is also at risk during TEA, particularly during exposure and dissection. Injury to this structure can result in compromised blood flow to the arm, posing a serious risk that often requires urgent vascular repair or revision of the implant to ensure proper circulation and limb viability.

Clinical and radiographic outcomes

The assessment of clinical and radiographic outcomes for TEA has evolved significantly over time, reflecting improvements in surgical techniques and implant designs, as well as a deeper understanding of patient needs.¹⁰⁷ Historically, clinical outcomes such as pain relief, range of motion, and restoration of function were the primary focus. Pain reduction was crucial for patients with conditions like RA, where the primary goal of surgery was pain relief and functional range of motion (ROM) for activities of daily living. In the early days of TEA, achieving a pain-free joint with functional ROM was deemed a success, even if some limitations in strength or fine motor control persisted. These outcomes laid the foundation for determining the procedure's overall effectiveness, guiding further refinements in technique and patient care.

The earliest radiographic assessments focused on implant positioning and potential complications like loosening or subsidence, monitoring for signs of bone resorption around the implant, which could indicate stress shielding or poor integration of the prosthesis with the surrounding bone.^45,93 Radiographic stability became a critical benchmark for long-term success, with well-fixed implants being a key predictor of sustained clinical outcomes. This concept was first described by Dee in 1972, who emphasized the importance of radiographic stability in predicting the longevity of TEA implants.¹⁷ Sustained clinical outcomes refer to the long-term benefits observed in patients, including pain relief, improved range of motion, and overall functional improvement.⁸⁹ Studies have shown that implants with radiographic stability are less likely to experience complications such as loosening, wear, or periprosthetic fractures, which are critical for maintaining these positive outcomes over time.

In recent years, there has been a shift to include newer clinical and radiographic outcomes that offer a more holistic view of TEA success. In addition to traditional measures like pain and range of motion, contemporary studies often assess patient-reported outcome measures, which are designed to reflect the patient's own perception of their function and quality of life postsurgery.^55,66 These tools allow clinicians to capture aspects such as satisfaction with the surgery, ease of performing daily activities, and the psychosocial impact of having a more functional elbow. Radiographically, new imaging techniques have improved the ability to assess soft tissue integrity and joint stability around the prosthesis, offering a more comprehensive understanding of how the entire joint is functioning postoperatively.

Specific radiographic evidence to assess for failure of TEA varies greatly. The primary method of radiographic assessment involves identifying progressive radiolucent lines at the bone-cement or bone-implant interface. Radiolucency greater than 2 mm in width or Morrey criteria greater than II is associated with poor outcomes and is considered radiographic failure.⁷² Besides radiolucent lines, radiographic analysis may reveal cement fragmentation, implant component migration, and bead shedding.²⁸

Current concepts

Optimizing patient selection

Optimizing TEA outcomes begins with thorough preoperative assessment and careful patient selection.^4,73 Historically, TEA was primarily reserved for patients with severe RA, where joint replacement could provide significant pain relief and restore function. However, selection criteria have evolved over time to take into account bone quality, comorbidities, and patient activity level. Early experiences with TEA highlighted that patients with severe osteoporosis or uncontrolled diabetes had higher rates of implant loosening and infection. Additionally, the indications for TEA have shifted over the years. Initially, TEA was primarily performed for RA, but there has been a notable increase in its use for acute trauma and osteoarthritis. Identifying patients who are likely to benefit most from TEA, while avoiding surgery for those at high risk of complications, may lead to improved overall outcomes and reduced the risk of postoperative complications, such as loosening or instability.

Candidates for TEA should be carefully assessed based on age, activity level, and bone quality.^22,85 Younger and highly active patients may place excessive mechanical stress on the implant, increasing the risk of wear and loosening. Additionally, patients with severe ligamentous insufficiency may require constrained implants to maintain joint stability. Any modifiable risk factors identified during the preoperative planning process, such as smoking cessation, weight management, diabetes control, and immunosuppressive therapy adjustments, should be addressed before surgery. Screening for infections, optimizing nutritional status, and ensuring bone health through vitamin D and calcium supplementation can further reduce the likelihood of postoperative complications and implant failure.

Improvements in surgical technique

Advancements in surgical techniques have also played a critical role in the success of TEA, reducing the likelihood of complications that could necessitate revision surgery. Initially, surgical approaches to the elbow were limited, leading to challenges in achieving proper alignment and soft tissue balance. However, as surgeons were able to overcome the initial surgical learning curve, techniques involved improved exposure methods and precise positioning of components, which helped to reduce the risk of instability and malalignment.⁶⁷ Additionally, the use of intraoperative imaging and enhanced training programs for surgeons has contributed to a decline in technical errors. These developments have allowed for more precise placement of the implant, better preservation of surrounding structures, and ultimately, longer-lasting results for patients.

Proper implant positioning and fixation are necessary to prevent early loosening and instability. Accurate component alignment ensures balanced load distribution, reducing stress concentration on the implant. Cementing techniques have been refined to achieve optimal interdigitation with the bone, providing stable fixation and preventing micromotion that can lead to loosening.

The growth of minimally invasive and navigation-assisted techniques has improved surgical precision, leading to better implant placement and reduced soft tissue trauma.^37,94 Robotic-assisted surgery and patient-specific instrumentation allow for enhanced accuracy, minimizing technical errors and improving postoperative function. These innovations contribute to improved implant longevity and lower revision rates.

Postoperative course and long-term follow-up

A structured rehabilitation protocol is essential to ensure proper joint function and prevent complications following TEA.¹⁴ Early, guided physical or occupational therapy helps to maintain ROM while avoiding excess stress on the implant. Skilled therapists play a key role in fine-tuning the intensity of postoperative rehabilitation, as overly aggressive therapy can lead to instability or triceps failure, while inadequate movement may result in stiffness and functional limitations. Historically the tendency was to withhold patients from early postoperative rehabilitation, which often led to stiffness or improper healing, which could threaten the longevity of the implant. With advances in postoperative care, such as structured physical therapy programs, patients are now better guided through exercises that ensure proper range of motion and strengthen the muscles around the elbow. This emphasis on guided rehabilitation has helped reduce complications and improve function after surgery.

Routine clinical and radiographic follow-up is necessary to detect early signs of implant failure. Early signs of failure that clinicians look for during follow-up visits include increased pain, swelling, and decreased range of motion. Patients should be educated on activity modifications to prevent undue strain on the implant. A significant aspect of these modifications is the lifelong weightlifting restriction of no more than 5-10 pounds.¹⁶ This restriction is crucial to prevent implant loosening and failure, particularly in young, active patients who may find it challenging to adhere to these limitations. Studies have shown that noncompliance with this restriction is a notable source of implant failure, with up to 30% of patients experiencing complications due to excessive loading.⁵ Historically, these restrictions have been in place since the early days of TEA to mitigate the risk of mechanical failure. While advancements in implant design and materials may eventually lead to more lenient guidelines, current evidence supports the continuation of these restrictions to ensure long-term implant success.

Long-term surveillance strategies, including periodic imaging and biomechanical assessments, help identify potential complications before they necessitate revision surgery. Collectively, these strategies have made a substantial difference in reducing complications and the need for revision surgeries, resulting in better long-term outcomes for patients undergoing TEA.

Conclusion

The historical evolution of TEA has been marked by significant advancements in implant materials and design, leading to improved outcomes and reduced failure rates. Early designs faced high failure rates due to poor biomechanics and material limitations, but modern implants have benefited from the use of advanced materials such as titanium alloys and CoCr components. These materials offer better biocompatibility, wear resistance, and mechanical properties, contributing to the longevity of the implants.

Despite these improvements, challenges remain in achieving long-term durability and function, particularly in younger and more active patients. Aseptic loosening, wear-related complications, periprosthetic fractures, implant fractures, infections, and instability continue to be significant causes of TEA failure. Advances in surgical techniques, patient selection criteria, and postoperative management have contributed to better outcomes, but further research is needed to address these persistent challenges.

Future directions should focus on optimizing implant biomechanics, developing biofilm-resistant materials, and integrating robotic-assisted surgical techniques. Additionally, patient education on activity modifications and adherence to postoperative guidelines are crucial for the success of TEA. By continuing to refine implant designs and surgical approaches, and by enhancing patient care, the field of TEA can achieve better long-term outcomes and improve the quality of life for patients undergoing this procedure.

Disclaimers:

Funding: No funding was disclosed by the authors.

Conflicts of interest: The authors, their immediate families, and any research foundations with which they are affiliated have not received any financial payments or other benefits from any commercial entity related to the subject of this article.