The Rate of Radial Head Prosthesis Removal or Revision: A Systematic Review and Meta-Analysis

Failed radial head arthroplasty treated by removal of the implant

Aims

In patients with a failed radial head arthroplasty (RHA), simple removal of the implant is an option. However, there is little information in the literature about the outcome of this procedure. The aim of this study was to review the mid-term clinical and radiological results, and the rate of complications and removal of the implant, in patients whose initial RHA was undertaken acutely for trauma involving the elbow.

Methods

A total of 11 patients in whom removal of a RHA without reimplantation was undertaken as a revision procedure were reviewed at a mean follow-up of 8.4 years (6 to 11). The range of motion (ROM) and stability of the elbow were recorded. Pain was assessed using a visual analogue scale (VAS). The functional outcome was assessed using the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score (OES), and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH). Radiological examination included the assessment of heterotopic ossification (HO), implant loosening, capitellar erosion, overlengthening, and osteoarthritis. Complications and the rate of further surgery were also recorded.

Results

The indications for removal of the implant were stiffness in five patients, aseptic loosening in five, and pain attributed to the RHA in three. The mean time interval between RHA for trauma to removal was ten months (7 to 21). Preoperatively, three patients had overlengthening of the implant, three had capitellar erosion, six had HO, and four had radiological evidence of loosening. At the final follow-up, the mean the flexion-extension arc improved significantly by 38.2° (95% CI 20 to 59; p = 0.002) and the mean arc of prono-supination improved significantly by 20° (95% CI 0 to 72.5; p = 0.035). The mean pain VAS score improved significantly by 3.5 (95% CI 2 to 5.5; p = 0.004). The mean MEPS improved significantly by 27.5 (95% CI 17.5 to 42.5; p = 0.002). The mean OES improved significantly by 9 (95% CI 2.5 to 14; p = 0.012), and the mean DASH score improved significantly by 23.5 (95% CI 7.5 to 31.6; p = 0.012). Ten patients (91%) had HO and osteoarthritis. Two patients underwent further surgery due to stiffness and pain, respectively.

Conclusion

Simple removal of the implant at revision surgery following a failed RHA introduced following trauma provides satisfactory mid-term results with an acceptable risk of complications. Osteoarthritis, instability, and radioulnar impingement were not problems in this series.

Uncementing the status quo: systematic review of a loose-fit, polished stem radial head prosthesis shows stable clinical results in complex elbow injuries with a concomitant radial head fracture

INTRODUCTION

Selecting the optimal radial head prosthesis to treat radial head fractures, especially in the context of complex elbow injuries like terrible triad, Monteggia, and Essex Lopresti, can be challenging, as there is currently no consensus in the field that favors a particular design. This study investigated the safety and performance of a Polished Stem Radial Head Prosthesis (PS RHP) compared to other modern RHP designs.

MATERIALS AND METHODS

A systematic review was conducted according to PRISMA guidelines to capture data on a Polished Stem Radial Head Prosthesis (PS RHP) and other Radial Head Prostheses (RHPs). Functional scores, range of motion, complications, and revisions were extracted from published literature and analyzed in parallel with the percentage of complex injuries. Comparison of functional outcomes between groups were based on minimum clinically important differences (MCIDs).

RESULTS

There were 16 articles reporting on 711 cases of the PS RHP and 23 articles reporting on 605 cases of other RHPs included in the systematic literature review. Functional scores and range of motion were similar amongst the groups. The PS RHP design achieved a comparable revision rate as other RHPs despite a higher number of terrible triad injuries. Notably, the PS RHP group showed a significantly lower rate of instability (1.0%) than other RHPs (3.4%) (p < 0.05). Other complication rates were similar amongst the two groups.

CONCLUSIONS

The PS RHP group had higher rates of terrible triads at baseline compared to the other RHPs group. Regardless of greater injury complexity, the clinical outcomes of the PS RHP group were favorable and resulted in a significantly lower rate of postoperative instability as compared to other RHPs.

Demographics, Indications, and Revision Rates for Radial Head Arthroplasty: Analysis of Data from the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Population-level data from national arthroplasty registries enable the use and outcomes of arthroplasty procedures to be monitored over time. This study aimed to describe the demographics, indications, and outcomes (up to 15 years) for radial head arthroplasty (RHA) procedures in Australia, as well as the factors associated with an increased likelihood of revision.

METHODS

Individual-level deidentified data on demographics and surgery characteristics, including revision surgery, were obtained from the Australian Orthopaedic Association National Joint Replacement Registry for all primary isolated RHA procedures that had been performed from 2007 to 2021. The probability of prosthesis survival was determined using Kaplan-Meier estimates. Cox proportional hazards models were used to calculate hazard ratios (HRs) for revision.

RESULTS

A total of 3,457 primary RHAs were performed during the study period (mean follow-up, 5.6 years; range, 0 to 15 years). The mean age at the time of RHA was 53 years, with female predominance (n = 2,009, 58%). The most common indication for RHA was fracture or dislocation (n = 3,166, 92%), followed by osteoarthritis (n = 232, 7%). The radial head prostheses that were most commonly used were monopolar (n = 3,378, 98%) with a modular design (n = 3,442, 99.6%) and cementless fixation (n = 3,387, 98%). Both metallic and nonmetallic prostheses were used (52% and 48%, respectively). Of the total cohort, 160 revisions (5%) were performed during the 15-year period; most revisions occurred in the first 5 years. The most common revision indication was prosthesis loosening (n = 62, 39%), and 54% of the revisions (n = 87) involved a change of the radial component. In multivariable analysis, primary procedures for osteoarthritis (HR, 1.65; 95% confidence interval [CI], 1.01 to 2.70) or "other" indications (e.g., inflammatory arthritis, osteonecrosis, or tumor) were revised more frequently (HR, 3.68; 95% CI, 1.14 to 11.91) than procedures for fracture or dislocation. Procedures with nonmetallic prostheses had higher rates of revision (HR, 1.61; 95% CI, 1.17 to 2.22) than those with metallic prostheses.

CONCLUSIONS

Trauma remained the most prevalent indication for RHA in Australia from 2007 to 2021. Encouragingly, revision rates were low, most notably for RHA that had been performed for fracture or dislocation. The likelihood of revision was highest for RHA procedures performed for osteoarthritis and for an indication other than osteoarthritis or trauma. Nonmetallic prostheses had a higher rate of revision than metallic prostheses.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Radial head arthroplasty diameter impact on elbow kinematics evaluated by dynamic radiostereometric analysis

Purpose

Radial head arthroplasty (RHA) reestablishes elbow stability after complex radial head fracture, but complication rates are high, possibly due to inappropriate implant sizing. Knowledge of impact of radial head implant diameter on elbow kinematics is limited and warranted. This study evaluated elbow kinematics of different radial head implant diameters after RHA using dynamic radiostereometric analysis (dRSA).

Methods

Eight human donor arms were examined with dRSA during elbow flexion with the forearm in unloaded neutral position, and in supinated- and pronated position without and with 10N either varus or valgus load, respectively. Elbow kinematics were examined before and after RHA with head diameters of anatomical size, -2 mm (undersized), and +2 mm (oversized). The ligaments were kept intact by use of step-cut humerus osteotomy for repeated RHA exchange. Bone models were obtained from CT, and by AutoRSA software bone models were matched with dRSA recordings. The elbow kinematics were described using anatomical coordinate systems.

Results

Compared to the native radial head during elbow flexion, the anatomical sized RHA shifted 2.0 mm in ulnar direction during unloaded pronated forearm position. The undersized RHA shifted 1.5 mm in posterior direction and 2.1 mm in ulnar direction during unloaded pronated forearm position and increased the varus angle by 2.4° during supinated loaded forearm position. The oversized RHA shifted 1.6 mm in radial direction during loaded supinated forearm position.

Conclusions

The anatomically sized RHA should be preferred as it maintained native elbow kinematics the best. The kinematic changes with oversized and undersized RHA diameters were small, suggesting forgiveness for the RHA diameter size.

Level of Evidence

Level III.

Revision of Failed Radial Head Arthroplasty

BACKGROUND

Revision of radial head arthroplasty (RHA) may be indicated in cases of prosthesis loosening and malposition. Inherent difficulties in revision surgery include poor bone stock and disrupted soft tissue envelope. Although cases of RHA used for revision of failed RHA are rare, there is reasonable expectation for increasing frequency of these cases due to the increasing incidence of primary RHA. Furthermore, there is an increasing demand for postoperative recovery of function; thus, surgeons may consider revising a failed RHA to a new RHA. We report on series of failed RHA which were revised to a new radial head prosthesis.

METHODS

A retrospective review was performed at multiple institutions for a single radial head prosthesis used for revision of a failed radial head prosthesis. Clinical and radiographic outcomes were collected with a minimum of 1 year of follow-up.

RESULTS

Across 11 patients at a mean follow-up of 45.1 months, the mean Mayo Elbow Performance Score was 81.7; mean Disabilities of the Arm, Shoulder, and Hand scores were 24.4; and mean Visual Analog Scale for pain was 0.6. Radiographic analysis yielded no evidence of capitellar wear or stem loosening.

CONCLUSION

A radial head prosthesis can produce satisfactory results when used for revision of a failed prosthesis. Inherent difficulties in revision surgery include the potential for reduced bone stock and a disrupted soft tissue envelope. Elements of prosthesis design which may contribute to effectively managing revision surgery include a long stem with in-growth surface and prosthetic head alignment to the axis of forearm rotation.

Pyrocarbon radial head arthroplasty offers satisfactory clinical and radiological outcomes with low revision rate: A systematic review

INTRODUCTION

Pyrocarbon promises to be an optimal material choice for radial head arthroplasty (RHA) due to an elastic modulus comparable to the radial diaphysis and thus providing higher biocompatibility. Primary objective was to determine the complications and revision rates related to the usage of these prostheses. The secondary objective was to assess the clinical and radiological outcomes of Pyrocarbon RHAs.

HYPOTHESIS

Pyrocarbon RHAs have good clinical and radiological outcomes with low complications and revisions.

METHODS

Ovid MEDLINE and Embase databases were used to search for studies on outcomes and complications of the RHAs using Pyrocarbon radial head prostheses. The systematic review was designed in accordance with the PRISMA guidelines and included studies were appraised using the MINORS tool. Complications and RHA revision rates were assessed. Functional outcomes were reviewed using PROMs (like MEPI, DASH and BMS), post-op range of motion (using goniometer) and grip strength (using the dynamometer). Postoperative radiological outcomes like peri-prosthetic lucency, radial neck osteolysis, radio-capitellar congruence, capitellar erosion, overstuffing/understuffing and osteoarthritis were reported using radiographs.

RESULTS

A total of 12 studies cumulatively reporting 353 patients who underwent Pyrocarbon RHAs were included in the review. The mean age of patients across the studies ranged from 47 to 54 years of which 50.5% were males. The majority of radial head replacements were done for acute trauma (87.5%) with the remainder done for arthritis (1.7%) and trauma sequelae (10.8%). Mean follow-up period in the selected studies ranged from 18 to 110 months with minimum follow-up across all studies being 12 months. Modular Pyrocarbon (MoPyC, Tornier™) was the implant of choice in ten studies while two studies used the Ascension Pyrocarbon radial head (Ascension Orthopaedics™). Ten studies demonstrated mean MEPI ranging from 75.5 to 96. Mean extension deficit ranged from 6 to 19 degrees, mean flexion from 120 to 140 degrees, mean pronation from 71 to 87 degrees and mean supination from 63 to 85 degrees. Relative grip strength ranged from 69 to 96% of the contralateral limb. Revisions due to implant-related reasons (intra-prosthetic dissociation, prosthetic fracture, peri-prosthetic loosening, radio-capitellar subluxation and understuffed/overstuffed elbow) was 6.8% (24/353). Radial stress shielding and peri-prosthetic lucency was reported in 10 to 100% of patients across different studies but symptomatic implant loosening leading to revision remained rare (2%, 7/353). Radio-capitellar congruence was reported in 81% to 100% cases while capitellar erosion ranged from 0% to 89%. Pyrocarbon implants specific complications included head-neck intra-prosthetic decoupling (1.1%) and pyrocarbon head fractures (0.9%). In total, 5.7% cases underwent re-surgery due to non-RHA related reasons.

DISCUSSION

The pyrocarbon RHA shows good functional outcome, range of motion and low revision rates. This aligns with the working hypothesis of this review. However, pyrocarbon radial head implants have implant-specific complications like pyrocarbon radial head fractures and intra-prosthetic decoupling between stem and head. Despite promising in vitro biomechanical properties, capitellar wear is still a common finding with pyrocarbon RHAs. Despite these factors, pyrocarbon radial head implants are a viable option for radial head arthroplasty.

LEVEL OF EVIDENCE

II; Systematic review.

Antibiotic-loaded spacer arthroplasty in a terrible triad injury with unreconstructable radial head fracture: a case report

BACKGROUND

Radial head arthroplasty is a viable option in cases with terrible triad injuries of elbow, wherein the radial head sustains significant comminution that precludes reconstruction. Nevertheless, this alternative is not recommended for individuals with poor elbow skin conditions, accompanied neuropsychiatric disorders, or low patient compliance. This case report presents a patient with bilateral terrible triad injury, along with the aforementioned conditions. The report outlines the treatment challenges of such a case and proposes potential solutions.

CASE PRESENTATION

A 37-year-old Persian male patient presenting with a bilateral terrible triad fracture-dislocation and a history of psychoactive substance abuse, was admitted to our emergency department. The patient underwent radial head replacement using a cement spacer containing antibiotics, due to the comminuted radial head in the presence of a contaminated wound on the left elbow. The fracture of the right side was successfully fixed. Subsequent to discharge, the patient did not attend any follow-up appointments. After a period of 6 months, he was admitted to the psychiatric ward and orthopedic consultation was requested to evaluate the patient.

CONCLUSION

In acute terrible triad injuries with unreconstructable radial head fractures where arthroplasty with metallic prostheses may not be suitable due to contaminated wounds, unstable psychiatric condition, and low patient cooperation, temporary orthopedic cement spacers can maintain elbow biomechanics, stability, and sterility.

Mid-term outcome following radial head arthroplasty in acute trauma: risk factors for poor outcome

BACKGROUND

The aims of this study were to evaluate the outcomes of a single type of radial head implant in a large cohort of patients at mid-term follow-up and to determine the associated risk factors for inferior functional outcomes.

METHODS

We performed a retrospective follow-up assessment of 65 patients (33 women and 32 men; mean age, 53.3 years [range, 22-81 years]) who underwent radial head arthroplasty (RHA) for acute trauma between 2012 and 2018, after a minimum follow-up period of 3 years. The Mayo Elbow Performance Score, Oxford Elbow Score, Disabilities of the Arm, Shoulder and Hand score, and Mayo Modified Wrist Score were evaluated, and all available radiographs were analyzed. All complications and revision procedures were assessed. Bivariate and multivariate regression analyses were performed to identify potential risk factors for a poor outcome following RHA.

RESULTS

After an average follow-up period of 4.1 years (range, 3-9.4 years), the mean Mayo Elbow Performance Score was 77.2 (standard deviation [SD], 18.9); mean Oxford Elbow Score, 32.0 (SD, 10.6); mean Mayo Modified Wrist Score, 74.6 (SD, 13.7); and mean Disabilities of the Arm, Shoulder and Hand score, 29.0 (SD, 21.2). Average range of motion measured 10° (SD, 15°) in extension, 125° (SD, 14°) in flexion, 81° (SD, 14°) in pronation, and 63° (SD, 24°) in supination. The overall complication and reoperation rates were 38.5% and 30.8%, respectively, with severe elbow stiffness being the most common reason for revision. Patient age >50 years, the use of an external fixator, the presence of accompanying medial collateral ligament injuries, and the development of higher-grade osteoarthritis were associated with a poor outcome.

CONCLUSION

Satisfactory medium-term outcomes can be achieved using a monopolar, long-stemmed RHA in patients with acute trauma. However, complication and revision rates are high, frequently leading to inferior outcome scores. Additionally, a higher patient age, the use of an external fixator, the presence of accompanying medial collateral ligament injuries, and the occurrence of higher-grade osteoarthritis were associated with a poor outcome; these factors should raise awareness by the treating trauma surgeon.

Assessment of progression and clinical relevance of stress-shielding around press-fit radial head arthroplasty

Aims

The aim of this study was to analyze how proximal radial neck resorption (PRNR) starts and progresses radiologically in two types of press-fit radial head arthroplasties (RHAs), and to investigate its clinical relevance.

Methods

A total of 97 patients with RHA were analyzed: 56 received a bipolar RHA (Group 1) while 41 received an anatomical implant (Group 2). Radiographs were performed postoperatively and after three, six, nine, and 12 weeks, six, nine, 12, 18, and 24 months, and annually thereafter. PRNR was measured in all radiographs in the four radial neck quadrants. The Mayo Elbow Performance Score (MEPS), the abbreviated version of the Disabilities of the Arm, Shoulder, and Hand questionnaire (QuickDASH), and the patient-assessed American Shoulder and Elbow Surgeons score - Elbow (pASES-E) were used for the clinical assessment. Radiological signs of implant loosening were investigated.

Results

The mean follow-up was six years (2 to 14). PRNR started after a mean of 7.5 weeks (SD 2.1) and progressed significantly during the first two years, by the end of which the bone resorption stabilized. PRNR was detected in 81% (n = 45) of patients in Group 1 and 88% (n = 36) in Group 2. The final mean PRNR was 3.0 mm (SD 2.3) in Group 1 and 3.7 mm (SD 2.5) in Group 2. The mean MEPS, QuickDASH, and pASES-E were 95.9 (SD 11.5), 4.4 (SD 9.2), and 94.8 (SD 10.9) in Group 1 and 92.2 (SD 16.2), 9.9 (SD 21.5), and 90.8 (SD 15) in Group 2, respectively. No significant differences were observed between groups in the clinical and radiological outcomes. No correlations were found between PRNR and the clinical results.

Conclusion

PRNR after press-fit RHA is a common radiological finding that develops in the first 24 months before stabilizing definitively. PRNR does not affect the clinical results or implant survival in the mid term.

Short- to Mid-term Results of Patient-Specific Polymethylmethacrylate Radial Head Prosthesis in Complex Radial Head Fractures Using 3-Dimensional Mold System

Background: We used antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement to make a patient-specific radial head prosthesis (RHP) by applying the 3-dimensional (3D) designing technique in patients with Mason types 3 and 4 radial head fractures. The aim of this study is to report the short- to mid-term outcomes of this procedure. Methods: This is a prospective study of all patients who underwent a patient-specific PMMA bone cement RHP at our institute over a 1-year period from May 2017 to June 2018. The outcome measures included range of motion, grip strength, visual analogue scale (VAS) for pain at rest and at activity, disabilities of arm, shoulder and hand (DASH) score and Mayo elbow performance index (MEPI). Radiographs of the elbow ere obtained at final follow-up and any complications were also recorded. Results: Our study included eight patients with a mean follow-up of 18 months (13-20 months). The mean arc of extension-flexion and supination-pronation of the operated side was 86% and 96% of the unaffected side, respectively. Mean grip strength was 86% of the unaffected side. The mean VAS for pain at rest was 0 and during activity was 2 out of 10. The mean DASH score was 8 out of 100 (0-22), showing minimal disability and ability to cope with most living activities. MEPI showed four excellent, three good and one fair result. One patient complained of proximal forearm pain that appeared 1 year after surgery. No patient complained of ulnar nerve symptoms requiring intervention. No RHP was removed during the follow-up. Conclusions: PMMA RHP can be used safely as an alternative to metal prostheses to restore valgus and axial stability of the forearm. The use of 3D printing optimised the design and surgical technique of radial head arthroplasty, and we need further studies to assess the long-term follow-ups. Level of Evidence: Level IV (Therapeutic).

Anatomic Monopolar Press-fit Radial Head Arthroplasty; High Rate of Loosening at Mid-Term Follow Up

Introduction

Radial head arthroplasty (RHA) is used for the management of unstable or unreconstructable injuries of the radial head. Our aim was to investigate clinical and radiographic outcomes in patients treated with the Acumed anatomic radial head press-fit system for trauma.

Methods

Clinical and radiographic assessment of RHAs undertaken for trauma with minimum 2-year follow-up.

Results

16 consecutive patients, mean age 53 (21-82) and 66 month ± 27 (26-122) clinical follow-up were included. There were marked radiographic changes with 11/16 showing periprosthetic lucent lines and 13/16 showing subcollar osteolysis. Radiographic changes occurred early post-surgery. Stem loosening was associated with larger cantilever quotients (0.47 vs 0.38, p  =  0.004). Overall survivability was 81.2%, with 3 RHAs removed. Clinical outcomes for the retained RHAs were acceptable with mean flexion 134°, extension deficit of 10°, pronation of 82°, and supination of 73°. Mean VAS scores were 8.5 ±  14.4, QuickDASH 13.8 ±  18.9, Mayo Elbow Performance Scores were 91.5 ±  12.5 with no poor scores.

Conclusion

Mid-term clinical functional outcomes following the Acumed anatomic RHA are acceptable in most cases. However, in view of the extensive periprosthetic lucencies and surgical removal due to loosening, patients should be cautioned when consented for implantation of the prosthesis, especially if a large collar is anticipated.

Early aseptic loosening of a press-fit radial head prosthesis - A case series of 6 patients

OBJECTIVE

Radial head arthroplasty (RHA) is the principal treatment option for comminuted radial head (RH) fractures. Here, we present six cases of failed RHA using a modular monopolar press-fit RHA that was subsequently withdrawn from the market because it was associated with a high incidence of loosening.

METHODS

We retrospectively collected data from six patients who had received Radial Head Prothesis System^TM at our centre between July 2015 and June 2016. The average follow-up was 40 months.

RESULTS

Aseptic loosening of the stem affected five (83%) of the six RHA. Four of these were symptomatic and RHA removal was performed. For these patients, the pain subsided and their elbow range of motion (ROM) improved.

CONCLUSION

While the ideal design for an RHA is still debatable, RHA is an efficient treatment option that restores elbow stability and function after a comminuted RH fracture. Importantly, removal of the prosthesis is an effective remedy following RHA associated elbow pain and decreased ROM.

The comparative performance of radial head prostheses in patients younger than and older than 50 years: a systematic review

Background

Patient age may play a role in the surgeon's decision between radial head arthroplasty (RHA) and open reduction internal fixation in radial head fracture treatment. Though large sample reports have detailed outcomes of radial head replacement for a mean age younger than 50 years, the age ranges are widely distributed. Patient outcomes are not uniform across a broad age distribution. Therefore, treatment decisions should be evaluated within the confines of a narrower age bracket. An understanding of clinical outcomes for radial head replacement in younger adults will provide value for guiding treatment decisions. We performed a systematic review comparing the clinical outcomes for radial head replacement in patients younger and older than 50 years of age. Further analysis compared outcomes between RHA performed as a primary procedure and as a secondary procedure in patients younger and older than 50 years of age.

Methods

PubMed was queried for articles which delineated individual patient data for age, surgical treatment, and appropriate outcome metrics. Articles were grouped based on patient age of under 50 and over 50 years and within those age groups, based on the arthroplasty being performed as a primary or as a secondary procedure.

Results

There were no significant differences between the under 50 and the over 50 groups for Mayo Elbow Performance Score (P = .79) and for implant revision/removal (P = .32). In the under 50 group, RHA done as a primary procedure had significantly higher (P = .001) mean Mayo Elbow Performance Score than RHA done as a secondary procedure. In the over 50 group, relative risk was 2.39 (95% confidence interval, 2.12-2.69) for implant revision/removal (P = .11) when comparing primary and secondary procedures.

Discussion

At a mean follow-up of 48 months, RHA in patients under the age of 50 years had satisfactory outcomes which were comparable to outcomes in patients over the age of 50 years. Across both age groups, arthroplasty performed as a primary procedure demonstrated superior outcomes compared to arthroplasty performed as a secondary procedure. Our findings provide guidance to surgeons who face a multifaceted decision when encountering younger adult patients with radial head fracture patterns that may not be amenable to fixation. Awareness of the age-specific performance of radial head implants is an important component of the decision for surgical treatment.

The Possibilities of Personalized 3D Printed Implants-A Case Series Study

Background and Objectives: Following the most recent software and 3D printing developments, the use of personalized 3D printed orthopedic implants for treatment of complicated surgical cases has gained more popularity. Today, orthopedic problems that cannot be solved with standard implants may be effectively addressed using personalized prostheses. The aim of this study is to present the designing, modeling and production stages of four different personalized 3D printed prostheses and their application in clinical cases of patients who underwent treatment in various anatomical locations with a precisely specified indication for implantation. Materials and Methods: Based on computed tomography scanning, personalized 3D printed prostheses were designed, produced and used in four patients within a period of three to five days after injury or admission. Results: Early term follow-ups demonstrated good to excellent results. Conclusions: Personalized 3D printed prostheses offer an opportunity for a treatment of choice and provide good anatomical and functional results, shortened surgical time, less complications, and high satisfaction in patients with appropriate indications. The method should be considered primarily for patients with large bone defects, or such indicated for resection. Personalized 3D printed prostheses have the potential to become more common and beneficial in the future.

Radiocapitellar Arthroplasty: Systematic Review

Introduction

Primary elbow osteoarthritis affects approximately 2% of the population, and has been treated with arthroplasty. However, total elbow arthroplasty (TEA) implants currently have severe weight limitations and issues with longevity. In patients with unicompartmental arthritis, unicompartmental arthroplasty may be used instead of TEA. We describe the use of Uni-Elbow Radio-Capitellum and Lateral Resurfacing Elbow for radiocapitellar arthroplasty (RCA) in this article.

Methods

Reviewers independently searched databases for keywords, such as radiocapitellar arthroplasty, RCA, uni-elbow radiocapitellum, UNI-E, and lateral resurfacing elbow, LRE. The measured outcomes of interest were the change in motion arc and patient-reported outcome scores. Studies that were not of appropriate quality determined by the Cochrane risk of bias summary tool and review studies were excluded.

Results

RCA resulted in a postoperative 38.3° ± 28.5° increase in elbow flexion-extension (P < .001), and 35.2° ± 28.6° increase in elbow pronation-supination (P < .001). Mayo Elbow Performance Score was significantly increased by 44.8 ± 12.6. DASH Score saw a significant reduction by 45.0 ± 14.6 points (P < .001), while the American Shoulder and Elbow Surgeons Score increased by 47.0 ± 10.6 points (P < .001). Of the 105 adult patients 16.2% experienced complications such as minor stiffness, ulnar neuropathy, component loosening, or radial head UNI-E stem failure. Reported complications were higher in the UNI-E group than in the LRE group.

Conclusion

RCA has shown promise as an option to treat radiocapitellar arthritis, particularly when excising the radial head causes lateral column instability.

A systematic review and meta-analysis on different stem fixation methods of radial head prostheses during long-term follow-up

Background: Radial head arthroplasty (RHA) is typically performed for non-reconstructible radial head fractures with or without valgus stability. The fixation methods can be divided into cemented rigid fixation, such as screw fixation, and uncemented micromovement fixation, including smooth stem, press-fit, expanded device, in-growth stem, and grit-blasted stem fixations. Different fixation methods may impact long-term clinical outcomes and cause complications. This study aimed to compare the long-term follow-up outcomes of cemented and uncemented radial head prostheses. Methods: A computerized literature search was performed in the PubMed/MEDLINE, Embase, Cochrane Library, and Web of Science databases for studies on radial head prostheses, replacement, and arthroplasty published from inception to April 2022. The prostheses fixation method was divided into cemented and uncemented fixation groups. The outcomes of interest included the participant characteristics, prostheses types, clinical outcomes, reoperation rates, and complication rates during long-term follow-up. Results: A total of 57 studies involving 2050 patients who underwent RHA were included in our analysis. Cemented fixation was used in 23 of these studies, uncemented fixation in 35 studies, and both cemented and uncemented fixations in one study. Both fixation groups showed significantly improved clinical outcomes after treatment. In particular, both the reoperation and complication rates were lower in the uncemented fixation group (12% and 22%, respectively) than that in the cemented fixation group (20% and 29%, respectively). Among the studies, uncemented monopolar fixation had the lowest reoperation rate (14%), while cemented monopolar fixation had the highest reoperation rate (36%). Regarding complication rates, uncemented bipolar fixation yielded the lowest rate (12%), while cemented bipolar fixation yielded the highest rate (34%). The range of motion and clinical outcome scores were good in both groups. Conclusion: Uncemented radial head prostheses had lower reoperation and complication rates than cemented prostheses. In particular, uncemented monopolar prostheses may yield the lowest reoperation rate, while uncemented bipolar prostheses may yield the lowest overall complication rate.

Survivorship of anatomic press-fit short-stem radial head replacement with a pyrocarbon bearing

BACKGROUND

Restoring the radial head as a stabiliser of the elbow is considered important in cases where there is an associated bony or ligamentous injury. A variety of radial head prostheses are available. There are no reports of the survivorship of a short-stem press-fit radial head prostheses with pyrocarbon bearing.

PATIENTS AND METHODS

With institutional review board approval, a retrospective case-note analysis was performed of a consecutive single-surgeon case series of the Integra LifeScience pyrocarbon radial head prostheses (Carbon Modular Radial Head) from October 2010 to October 2019 in a tertiary referral centre. The series was divided into acute trauma and salvage cohorts. Kaplan-Meier survivorship analysis was conducted.

RESULTS

36 patients were included, 23 (64%) for acute injuries and 13 (36%) for failed initial treatment. Of the acute injuries, 20 (87%) had a Wrightington type-C elbow fracture-dislocation. Reoperation was performed in 4 (11%) patients; 10 (28%) had possible loosening on radiographs. The implant survival rate was 94% at shortest follow-up of 17 months (mean 70 months).

DISCUSSION

Treatment of complex radial head fractures using a pyrocarbon-bearing, anatomic press-fit design provides satisfactory short-term survivorship in this case series. The implant should be used with caution in salvage cases, due to higher rates of loosening seen in this cohort.

Pathologic Periprosthetic Fracture After Radial Head Arthroplasty: A Report of 2 Cases

CASE

We present 2 cases of pathologic periprosthetic radius fractures in the setting of osteolysis after radial head arthroplasty (RHA) with a porous-coated, press-fit implant. Both patients were managed with implant removal without subsequent instability. Although radiographic lucencies are common after RHA, progressive bone resorption can result in subsequent periprosthetic fractures.

CONCLUSION

Although osteolysis after RHA is not always clinically significant, these cases demonstrate that this radiographic finding may indicate adverse clinical consequences. Surgeons who perform implant excision should be ready to address further instability as needed.

LEVEL OF EVIDENCE

Level V, case reports.

Radial head arthroplasty: a descriptive study of 970 patients in an integrated health care system

BACKGROUND

Radial head arthroplasty (RHA) is commonly performed for isolated comminuted radial head fractures and in conjunction with traumatic elbow instability. However, there is a paucity of literature directly describing the characteristics and outcomes of patients who undergo RHA in a community-based setting. We describe a cohort of 970 RHA performed in the California regions of a US integrated health care system over a 9-year period. Patient demographics, implant selection, 90-day acute postoperative events, and cumulative reoperation/revision rates are included.

METHODS

Patients aged ≥18 years who underwent primary RHA were identified (2009-2017). Patient characteristics and demographics, including age, body mass index, gender, diabetes status, American Society of Anesthesiologists (ASA) classification, primary diagnosis, and concomitant procedures were described. Crude cumulative revision and reoperation probabilities were calculated as 1 minus the Kaplan-Meier estimator, with follow-up time calculated as the time from the index RHA to revision/reoperation date for those with the outcome of interest and time from index RHA to censoring date (eg, date of death, health care termination, study end date [March 31, 2018]) for those without the outcome. Ninety-day postoperative incidence of emergency department (ED) visit, readmission, and mortality was calculated as the number of patients with the event of interest over the number of patients at risk.

RESULTS

A total of 970 patients underwent primary unilateral RHA by 205 surgeons during the study period. Annual procedure volume increased from 53 procedures in 2009 to 157 procedures in 2017. More patients were female, without diabetes, and had an ASA classification of 1 or 2. Fracture was the predominant indication for RHA (98.4%) and more than half (54.3%) had concomitant procedures performed. Most implants were press fit (63.2%) over loose fit, and >90% were monopolar. Three-year cumulative revision and reoperation probabilities following RHA were 6.5% (95% confidence interval [CI] = 5.0%-8.5%) and 8.2% (95% CI = 6.5%-10.3%), respectively. Revisions and reoperations tended to occur within the first postoperative year. Of the 970 RHA patients, 83 (8.5%) had a 90-day ED visit, 58 (6.0%) had a 90-day readmission, and 1 (0.1%) died within a 90-day postoperative period.

CONCLUSION

This large cohort of RHA patients provides information about the practice of RHA at large and in the community. Surgeons are performing more RHA over time and choosing press fit stems more often. Revisions and reoperations tended to occur early. Readmission and ED visits were low but not negligible, with pain being the most common reason for ED visit.

Efficacy and safety of monopolar versus bipolar radial head arthroplasty: a systematic review and meta-analysis

BACKGROUND

Radial head replacement is the main line of treating complex unstable elbow injuries. Radial head prostheses are either monopolar or bipolar. The difference between both designs in patients' clinical outcomes and postoperative complications is not yet clear. So, a systematic review and meta-analysis was conducted to evaluate the efficacy and safety of monopolar vs. bipolar implants.

MATERIALS AND METHODS

PubMed, EMBASE, Cochrane, and Scopus were searched to identify studies comparing monopolar and bipolar implants. Data on clinical outcomes, postoperative complications, revision, and removal rates were extracted.

RESULTS

Nine studies met our inclusion criteria, with a total of 591 patients (365 monopolar and 226 bipolar). Both prostheses achieved similar ranges of motion; Mayo Elbow Performance Score; Disabilities of the Arm, Shoulder, and Hand score; and visual analog scale for pain. Incidence of postoperative complications was also similar between both designs. Revision and removal rates were 24%, 8% and 29%, 14% for monopolar and bipolar implants, respectively, but no statistically significant difference could be detected.

CONCLUSIONS

No significant difference was found between monopolar and bipolar radial head prostheses in terms of efficacy and safety. Therefore, high-quality randomized controlled trials are required to determine the superiority of one design over the other.

A registry study on radial head arthroplasties in the Netherlands: Indications, types and short-term survival

BACKGROUND

This study aims to use the Dutch Arthroplasty Register data to report an overview of the contemporary indications and implant designs, and report the short-term survival of radial head arthroplasty.

METHODS

From the Dutch Arthroplasty Register, data on patient demographics, surgery and revision were extracted for radial head arthroplasties performed from January 2014 to December 2019. Implant survival was calculated using the Kaplan-Meier method.

RESULTS

Two hundred fifty-eight arthroplasties were included with a median follow-up of 2.2 years. The most common indication was a fracture of the radial head (178, 69%). One hundred thirty-nine (68%) of the prostheses were of bipolar design, and the most commonly used implant type was the Radial Head System (Tornier; 134, 51%). Of the 258 included radial head arthroplasties, 16 were revised at a median of six months after surgery. Reason for revision was predominantly aseptic loosening (9). The overall implant survival was 95.8% after one year, 90.5% after three years and 89.5% after five years.

DISCUSSION

For radial head arthroplasties, acute trauma is the most common indication and Radial Head System the most commonly used implant. The implant survival is 89.5% after five years.

Retrospective review of pyrocarbon radial head replacement

Background

Radial head arthroplasty is the preferred surgical management for complex, unreconstructable radial head fractures. There has been increasing use of pyrocarbon prostheses, with potential tribology and modulus advantages over metallic counterparts. This study aims to assess clinical and radiological outcomes for radial head replacement after trauma using a modular, uncemented pyrocarbon prosthesis.

Materials and Methods

Between September 2009 and March 2020, a consecutive series of 22 trauma cases were available for review. Patients underwent radial head arthroplasty using a pyrocarbon prosthesis (Ascension Modular Radial Head System, Austin, TX). Recorded outcomes included clinical assessment, radiological evaluation, and patient-reported outcome measures specific to elbow function.

Results

Twenty-two patients (7 male, 15 female) with an average age of 51 years (range 21-64) were analyzed with a minimum 12 months of follow-up. All patients had complex radial head fractures, categorized as a Mason 3 or 4 injury. At follow-up, mean elbow range of motion included flexion 130° (range 100°-150°), extension 19° (0-50°), pronation 73° (30°-90°), and supination 70° (10°-90°). The mean Mayo Elbow Performance Index score was 83 (55-100), and Disabilities of the Arm, Shoulder and Hand score was 22 (2.5-60). Radiological evaluation showed 14 patients with asymptomatic proximal neck resorption and two patients with radiological stem loosening. In total, 3 of 22 implants were revised-2 were excised, and 1 revised to a long stem for traumatic implant fracture.

Conclusion

Pyrocarbon radial head arthroplasty provided reliable functional results for patients after unreconstructable radial head fracture. The unique potential for fracture of the prosthesis should be considered in long-term follow-up, with appropriate activity advice to patients.

Correlations Between Radial Head Diameters and Humeral Articular Dimensions: Bilateral MRI Morphometric Analysis on 39 Healthy Subjects

PURPOSE

Choosing the correct size of head component in radial head arthroplasty is often challenging, particularly in comminuted fractures, deformities, and revision surgery. The main aim of this study was to investigate possible correlations between radial head diameters and the morphometric parameters of the articular distal humerus in order to find mathematical equations that may be used to infer radial head dimensions indirectly.

METHODS

We performed bilateral elbow magnetic resonance imaging on 39 healthy young subjects, comprising 19 women and 20 men, with a mean age of 28 years (range, 21-32 years). The following measurements, which included cartilage thickness, were calculated on the axial plane: maximum (Dmax) and minimum (Dmin) radial head diameters, capitellum width, capitellum to lateral trochlear ridge width (CAP-TROCHridge), humeral articular width (HUMwidth), capitellum radius of curvature, and lateral, medial, and total trochlear width. The anteroposterior diameters of the capitellum, trochlear sulci, and lateral and medial trochlear ridges were measured on the sagittal plane.

RESULTS

CAP-TROCHridge and HUMwidth were found to be the parameters most strongly correlated with the radial head diameters. Four mathematical equations that allowed Dmax and Dmin to be calculated with an average residual error less than 1 mm, were obtained. The intraclass coefficient was greater than 0.95 for all the measurements.

CONCLUSIONS

Radial head diameters can be accurately inferred from 2 humeral dimensions by magnetic resonance imaging. The HUMwidth, which is not influenced by cartilage thickness, may be useful for planning with preoperative imaging because it can also be calculated by computed tomography scan, whereas CAP-TROCHridge, which is influenced by cartilage thickness, might be useful for direct intraoperative measurement.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic III.

RADIAL head arthroplasty: does ligaments repair influence outcomes? A minimum two years follow-up radiographic multi-center study

PURPOSE

The current indication for comminuted radial head fractures is radial head arthroplasty (RHA). The main purpose of this study was to investigate any statistical differences in terms of prosthesis revision or removal and radiographic degenerative changes by comparing patients who underwent RHA and ligaments repair to those who underwent only RHA implant at minimum two years follow-up. The secondary aim was to delineate a trend profile of RHA implants.

METHODS

All patients who underwent RHA surgery for traumatic pathology between January 2012 and December 2017 were eligible. Two researchers independently and retrospectively reviewed the patients' charts and collected the following data: type of prosthesis, associated surgical procedures and revision surgery. They also looked for any radiographic sign of prosthesis loosening, overstuffing, capitellar osteopenia, heterotopic ossification and degenerative changes. No clinical evaluation was performed.

RESULTS

In 6 years, 124 RHA were implanted (74 female, 50 male, mean age 56). The main diagnoses were: terrible triad, trans-olecranon fracture and isolated radial head fracture. It was found no significant statistical difference between the 2 groups; nevertheless, the cohort of patients that underwent ligaments repair had a lower revision rate in comparison with the other. Suture of the annular ligament seems to be critical. The overall revision rate was 10.5%.

CONCLUSION

This multi-center study found no evidence that ligaments repair, as an associated surgical procedure, improves RHA longevity, except for annular ligament. Nevertheless, it seems to prevent degenerative changes at midterm follow-up.

Risk Factors for Revision Surgery Following Radial Head Arthroplasty without Cement for Unreconstructible Radial Head Fractures: Minimum 3-Year Follow-up

BACKGROUND

Revision rates following radial head arthroplasty (RHA) for unreconstructible radial head fractures (RHFs) differ vastly in the literature, and little is known about the risk factors that are associated with revision surgery. The purposes of this study were to assess the revision rate following RHA and to determine the associated risk factors.

METHODS

A total of 122 patients (mean age, 50.7 years; range, 18 to 79 years) with 123 RHAs who underwent RHA for unreconstructible RHFs between 1994 and 2014 and were ≥3 years out from surgery were included. Demographic variables, injury and procedure-related characteristics, radiographic findings, complications, and revision procedures were assessed. Cox regression analysis was performed to identify the risk factors that were associated with revision surgery following RHA.

RESULTS

The median follow-up for the study cohort was 7.3 years (interquartile range [IQR], 5.1 to 10.1 years). All of the patients had unreconstructible RHFs: Mason-Johnston type-IV injuries were the most prevalent (80 [65%]). One or more associated osseous or ligamentous injuries were seen in 89 elbows (72.4%). The median time to surgery was 7 days (IQR, 3 to 11 days). Implanted prostheses were categorized as rigidly fixed (65 [52.8%]) or loosely fixed (58 [47.2%]). A total of 28 elbows (22.8%) underwent revision surgery at a median of 1.1 years (IQR, 0.3 to 3.8 years), with the majority of elbows (17 [60.7%]) undergoing revision surgery within the first 2 years. The most common reason for revision surgery was painful implant loosening (14 [29.2% of 48 complications]). Univariate Cox regression suggested that Workers' Compensation claims (hazard ratio [HR], 5.48; p < 0.001) and the use of an external fixator (HR, 4.67; p = 0.007) were significantly associated with revision surgery.

CONCLUSIONS

Revision rates following RHA for unreconstructible RHFs are high; the most common cause for revision surgery is painful implant loosening. Revision surgeries are predominantly performed within the first 2 years after implantation, and surgeons should be aware that Workers' Compensation claims and the use of an external fixator in management of the elbow injury are associated with revision surgery.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Factors influencing the mid-term radiological and functional outcomes of 41 post-fracture bipolar radial head arthroplasty cases at a mean follow-up of 87 months

INTRODUCTION

When treating comminuted radial head fractures that cannot be adequately fixed, the next option is arthroplasty (radial head replacement). We hypothesized that the radiological and functional outcomes of bipolar mobile cup radial head arthroplasty is not influenced by the length of follow-up but instead by the correct positioning of the implant intraoperatively and by the presence of associated bone or ligament injuries.

PATIENTS AND METHODS

Between May 1998 and December 2016, 82 cases of radial head arthroplasty were performed at our hospital. The mean age of patients at the time of arthroplasty was 53 years (22-81). Ligament or bone injuries complicated the radial head fractures in 70% of patients.

RESULTS

For the final assessment, 41 patients were reviewed and included in the statistical analysis with a mean of 82 months (12-228). The mean MEPS at the final assessment was 88.7 (61-100). There were 23 excellent, 9 good, 9 average and 0 poor results. The average DASH score was 18.7 (0-55). The average VAS for pain was 1.0 (0-5). Five patients (12%) required surgical revision, including one implant change. Our statistical analysis found no relationship between follow-up time and functional outcomes. The appearance of periprosthetic radiolucent lines was not affected by the length of follow-up. Associated bone or ligament injuries significantly increased the probability of periprosthetic radiolucent lines, humeroulnar joint degeneration and decentering of the implanted cup. Radiological evidence of a suspended implant was associated with significantly worse functional outcomes.

CONCLUSION

This study confirms the long-term stability of the clinical outcomes of radial head arthroplasty. There was no relationship between worsening radiological appearance of the implant and the clinical outcomes. It is critical that this implant not be oversized or suspended, as this can trigger premature capitellar erosion and painful stiffness of the operated elbow.

LEVEL OF EVIDENCE

IV; systematic retrospective analysis.

3D printing-assisted fabrication of patient-specific antibacterial radial head prosthesis with high periprosthetic bone preservation

We present a novel fabrication and surgical approach for anatomical reconstruction of a fractured radial head using patient-specific radial head prosthesis made of polymethylmethacrylate (PMMA) bone cement. To this end, the use of PMMA bone cement for prosthesis fabrication was initially investigated using computational modeling and experimental methods. The radial head prosthesis was fabricated through casting of PMMA bone cement in silicone mold in the operation room before implantation. To enhance the precision of bony preparation for replacement of the radial head, patient-specific surgical guide for accurate resection of the radial neck with the desired length was developed. Post-surgical clinical examinations revealed biomechanical restoration of elbow function, owing to the use of patient-specific radial head prosthesis and surgical guide. Importantly, follow-up radiographs after a mean follow-up of 18 months revealed bone preservation at the bone-prosthesis interface without any signs of erosion of the capitellum. Taken together, our method demonstrated the safety and efficacy of the PMMA radial head prosthesis in restoring elbow biomechanics. This also provides a very safe and cost-effective method for making various patient-specific prostheses with localized antibacterial delivery and close mechanical properties to native bone for improved periprosthetic bone regeneration.

Overlengthening of the radial column in radial head replacement: a review of the literature and presentation of a classification system

BACKGROUND

Radial head arthroplasty is a common procedure in elbow surgery. It has been shown to be of benefit for the patients, but there also are relevant complications that should be prevented if possible. One significant complication is overlengthening of the radial head prosthesis. In overlengthening, the head of the prosthesis overextends the physiological level of the native radial head and leads to overcompression in the radiohumeral joint. Rapid erosion and arthritic changes may then impede the clinical outcome. The incidence of overlengthening is not precisely known, but estimations range to up to 20% of all implanted prostheses.

METHODS

The present review discusses the available body of literature on overlengthening and lines out a classification system that may be used to guide treatment algorithms. The classification is based on the personal experiences of the author during their clinical practice.

RESULTS

In low-grade overlengthening (type I) conservative treatment can be an option. In Types II-IV usually revision surgery is needed. Depending on the state of the capitulum and joint stability, it is possible re-implant a prosthesis, or rely on implant removal alone.

DISCUSSION

The present review aimed at shedding light into overlengthening as a complication radial head replacement and to help identify and treat it.

Surgical treatment of the radial head is crucial for the outcome in terrible triad injuries of the elbow

AIMS

To evaluate the outcomes of terrible triad injuries (TTIs) in mid-term follow-up and determine whether surgical treatment of the radial head influences clinical and radiological outcomes.

METHODS

Follow-up assessment of 88 patients with TTI (48 women, 40 men; mean age 57 years (18 to 82)) was performed after a mean of 4.5 years (2.0 to 9.4). The Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and Disabilities of the Arm, Shoulder and Hand (DASH) score were evaluated. Radiographs of all patients were analyzed. Fracture types included 13 Mason type I, 16 type II, and 59 type III. Surgical treatment consisted of open reduction and internal fixation (ORIF) in all type II and reconstructable type III fractures, while radial head arthroplasty (RHA) was performed if reconstruction was not possible.

RESULTS

At follow-up the mean MEPS was 87.1 (20 to 100); mean OES, 36.9 (6 to 48); and mean DASH score, 18.6 (0 to 90). Mean movement was 118° (30° to 150°) for extension to flexion and 162° (90° to 180°) for pronation to supination. The overall reoperation rate was 24%, with nine ORIF, ten RHA, and two patients without treatment to the radial head needing surgical revision. When treated with RHA, Mason type III fractures exhibited significantly inferior outcomes. Suboptimal results were also identified in patients with degenerative or heterotopic changes on their latest radiograph. In contrast, more favourable outcomes were detected in patients with successful radial head reconstruction after Mason type III fractures.

CONCLUSION

Using a standardized protocol, sufficient elbow stability and good outcomes can be achieved in most TTIs. Although some bias in treatment allocation, with more severe injuries assigned to RHA, cannot be completely omitted, treatment of radial head fractures may have an independent effect on outcome, as patients subjected to RHA showed significantly inferior results compared to those subjected to reconstruction, in terms of elbow function, incidence of arthrosis, and postoperative complications. As RHA showed no apparent advantage in Mason type III injuries between the two treatment groups, we recommend reconstruction, providing stable fixation can be achieved. Cite this article: Bone Joint J 2020;102-B(12):1620-1628.

Intraosseous Plate Reduction and Fixation of Complex Proximal Ulnar Fractures: A Report of 2 Cases

CASE

We describe 2 cases using a novel technique of intraosseous plating of the coronoid as a reduction tool and fixation construct for complex elbow fracture dislocations. Each patient sustained traumatic, complex injuries of the elbow and were radiographically healed at the final follow-up.

CONCLUSION

Elbow fracture dislocations are complex injuries because of the interplay between primary and secondary stabilizers. This technique provides access to fracture fragments with minimal to no soft-tissue disruption and does not obstruct additional reduction or fixation of the injury.

Acute radial head replacement with bipolar prostheses: midterm results

In irreparable radial head fractures, especially if primary stabilizers of the elbow are damaged, the prosthetic replacement prevents instability and stiffness. Concerns have arisen over the use of bipolar press-fit prostheses due to the frequent finding of osteolysis and the risk of instability if compared to monopolar implants. Our aim was to assess midterm clinical and radiological outcomes of bipolar implants and the influence of osteolysis on proximal pain. Seventeen patients with irreparable fractures of the radial head, treated in acute with the same prosthetic model (rHEAD recon SBI/Stryker) between January 2015 and December 2018, were enrolled. Clinical assessment was performed using MEPS and DASH scores; a radiographic study was done to identify heterotopic ossifications and periprosthetic osteolysis. Outcomes at the last follow-up, according to MEPS, were excellent in 10 cases, good in 5 and fair in 2; none of the patients had severe pain or instability. In 3 cases, it was necessary to remove the implant, mainly because of early loosening. Radiological findings of osteolysis were detected in 9 cases, but no statistical correlation was found with MEPS and proximal pain. The use of bipolar implants is reliable if an accurate repair of ligament tears is performed and provides a good stability. Nevertheless, the risk of early aseptic loosening in uncemented implants is not negligible, and the follow-up of the patient must be strict. Late osteolysis does not seem to have clinical relevance, but further prospective studies are necessary to clarify this topic.

Acute Joint Blockage due to Abrasion-Related Dislocation of a Silastic Radial Head Prosthesis: A Histological Examination after 14 Years of Durability

The implantation of a radial head prosthesis can take place as a therapeutic option after radial head fracture. There are various implants for this purpose. Many studies and case reports about silastic radial head prosthesis implantation describe foreign body reactions with accompanying synovitis and poor functional results. A few studies have investigated the reason for the material failure and the accompanying synovitis. The case report presented shows an unusually long durability of an in situ 14-year silastic radial head prosthesis. 14 years after implantation, a previously full-time working and healthy patient presented himself with a dislocation of the silastic radial head prosthesis and atraumatic joint blockage of the right elbow triggered by a negligible movement. The prosthesis was removed surgically. We found a macroscopic foreign body reaction intraoperatively. In a histopathological examination, with hematoxylin and eosin staining (HE) in 40x and 100x magnification, we have seen an aseptic inflammatory response to foreign bodies with activated epithelial cells and multinucleated giant cells with intracytoplasmic foreign material. Due to these problems, the silastic radial head prosthesis is no longer used today. However, there are still patients with the implanted silastic radial head prosthesis, which should therefore be checked regularly. A metal prosthesis also does not seem to be an optimal alternative due to cartilage wear and loss of ROM. The choice of prosthesis material should be selected carefully and patient-specific in radial head prosthetics according of the results presented.

Management of the failed radial head arthroplasty

Primary radial head arthroplasty (RHA) produces good or excellent results in approximately 85% of patients. However, complications are not uncommon and have been described in up to 23% of cases.

The number of RHA is increasing, and consequently the absolute number of complications is expected to rise as well. The decision on whether to revise or remove the prosthesis seems more likely to depend on the preference of the surgeon or the hospital, rather than on objectifying problems with the prosthesis.

The current article presents an algorithm for the work-up and treatment of most complications that can occur following RHA.

Five subgroups of problems were identified: osteoarthritis, stiffness, instability, infection and implant-related issues.

In short, the preferred treatment depends mainly on the chondral condition and stability of the elbow joint.

Cite this article: EFORT Open Rev 2020;5:398-407. DOI: 10.1302/2058-5241.5.190055

Comparison of bipolar and monopolar radial head prostheses in elbow fracture-dislocation

INTRODUCTION

The role of bipolar radial head prostheses (RHP) in elbow fracture-dislocation is controversial, with some reports of poorer stabilization than with monopolar designs. The aim of the present study was to compare mono- versus bi-polar RHPs in elbow fracture-dislocation. The study hypothesis was that mono- and bi-polar RHPs do not differ in clinical and radiological results, complications or revision rates.

MATERIAL AND METHODS

A single-center retrospective study included 58 patients, with a mean age of 55 years (range, 21-84 years). All received RHP for elbow dislocation with association: terrible triad, Monteggia fracture-dislocation, transolecranal dislocation or divergent dislocation. Two groups were compared: Mono-RHP, with monopolar prosthesis (n=40), and Bi-RHP, with bipolar prosthesis (n=18). All patients underwent clinical and radiological examination at last follow-up.

RESULTS

Mean follow-up was 42.7 months (range, 12-131 months). There were no significant (p>0.05) inter-group differences in range of motion or Mayo Elbow Performance Score. Mono- versus bi-polar design did not correlate with onset of complications (p=0.89), surgical revision (p=0.71), persistent or recurrent instability (p=0.59), or ulnohumeral (p=0.62) or capitulum (p=0.159) osteoarthritis at last follow-up.

DISCUSSION AND CONCLUSION

No differences were found between mono- and bi-polar RHPs in the treatment of elbow fracture-dislocation. Clinical and radiographic results were similar, as were complications and revision rates. The literature is inconclusive, reporting contradictory conclusions. We see no contraindications to bipolar RHPs in elbow dislocation with association, notably terrible triad injury.

LEVEL OF EVIDENCE

III, Retrospective case-control study.

Why does radial head arthroplasty fail today? A systematic review of recent literature

Since the introduction of the radial head prosthesis (RHP) in 1941, many designs have been introduced. It is not clear whether prosthesis design parameters are related to early failure. The aim of this systematic review is to report on failure modes and to explore the association between implant design and early failure.A search was conducted to identify studies reporting on failed primary RHP. The results are clustered per type of RHP based on: material, fixation technique, modularity, and polarity. Chi-square tests are used to compare reasons for failure between the groups.Thirty-four articles are included involving 152 failed radial head arthroplasties (RHAs) in 152 patients. Eighteen different types of RHPs have been used.The most frequent reasons for revision surgery after RHA are (aseptic) loosening (30%), elbow stiffness (20%) and/or persisting pain (17%). Failure occurs after an average of 34 months (range, 0-348 months; median, 14 months).Press-fit prostheses fail at a higher ratio because of symptomatic loosening than intentionally loose-fit prostheses and prostheses that are fixed with an expandable stem (p < 0.01).Because of the many different types of RHP used to date and the limited numbers and evidence on early failure of RHA, the current data provide no evidence for a specific RHP design. Cite this article: EFORT Open Rev 2019;4:659-667. DOI: 10.1302/2058-5241.4.180099.

Correlation between radiographic findings and clinical failure in monopolar radial head replacement

INTRODUCTION

The purpose of this study is to analyze the mid-term outcomes of a modular monopolar type of radial head arthroplasty in the treatment of complex fractures associated with acute elbow joint instability. We postulated that radiographic changes are related to the development of clinical complications.

MATERIALS AND METHODS

We evaluated at last follow-up 26 radial head arthroplasties in 26 consecutive patients who were followed for at least one and a half year. All patients had suffered radial head fractures (Mason III) in the context of unstable elbow injuries. Definitive treatment of the radial fracture was performed with modular and monopolar prosthesis which was inserted as a press fit. All patients were evaluated preoperatively and postoperatively. The evaluation included a clinical examination and a protocolized imaging study (standard X-Rays and CT) of the elbow. We analyzed the incidence of: heterotopic ossifications, secondary radiocapitellar joint osteoarthritis, hardware loosening, hardware disengagement, and joint infection. Diagnosis of clinical failure of the implant was defined as the time to the second surgery due to major complications related to the prosthesis, such as persistent lateral side pain or elbow stiffness and any kind of implant instability or dislocation.

RESULTS

The implant-specific reoperation rate was 15% (four reoperations). The need for the second surgery was statistically associated with heterotopic ossifications, radiocapitellar osteoarthritis and cortical resorption around radial neck (p = 0.054, p = 0.033, and p = 0.019, respectively), being periprosthetic osteolysis the most likely factor related to failure, and radial pain the main symptom leading to surgical revision.

CONCLUSIONS

Our study shows a positive association between radiographic findings and patient symptoms for postoperative complications after radial head arthroplasty. Failed radial head replacements may lead to reoperation mainly due to pain, and this can be distinguished from other causes of pain in elbow region based on its radial location. Radiological loosening was prevalent in this group of failed replacement.

Preserving the radial head in comminuted Mason type III fractures without fixation to the radial shaft: a mid-term clinical and radiographic follow-up study

BACKGROUND

The treatment of multifragment Mason type III fractures is challenging. Open reduction-internal fixation (ORIF), radial head arthroplasty, and in some cases, even radial head resection are the current options; however, each of these treatment methods is associated with characteristic benefits and complications. We present our experience with a radial head salvage procedure in comminuted radial head fractures irrespective of concomitant injuries, which are not accompanied by typical ORIF-related complications.

METHODS

The first group comprised 29 patients with multifragment Mason type III fractures treated surgically with biological radial head spacers (group S). The fragments were reduced and fixated in an extracorporeal manner, and the reconstructed radial head was placed in its anatomic position without fixation to the shaft. The second group comprised 12 patients treated with conventional ORIF using mini-fragment plates (group P).

RESULTS

Thirty patients were enrolled to undergo clinical and radiographic follow-up at an average of 76 months (range, 12-152 months). In group S, nonunion at the head-neck junction developed in 70% of the cases; however, the overall Mayo Elbow Performance Index averaged 94.8, which was superior to the average Mayo Elbow Performance Index of 83.1 in group P. Radiographic evaluation showed development of osteoarthritic changes in 75% of patients in group S and 62.5% in group P. None of the patients had wrist-joint pain.

CONCLUSIONS

Preserving the native radial head in comminuted Mason type III fractures without fixation to the radial shaft is a reliable option. Excellent functional results can be expected; however, the development of osteoarthritis cannot be impeded.

Metallic Press-fit Radial Head Replacement for Radial Head Fractures

This study evaluated the clinical and radiographic results of patients who sustained nonreconstructible radial head fractures that subsequently were treated with a metallic press-fit radial head prosthesis (RHP). Nine patients with comminuted radial head fractures were treated with a metallic press-fit RHP; mean follow-up was 38.7 months. The radial head fracture was acute in 6 patients (group A) and chronic in 3 patients (group B). Functional evaluation was assessed using the Mayo Elbow Performance Score (MEPS) and Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire. Radiographs were assessed for loosening, radiocapitellar alignment, osteolysis of the radial neck, lucency, periarticular ossifications, and ulnohumeral degeneration. Average flexion and flexion contracture were 133° and 5°, respectively. Average supination and pronation angles were 70° and 73°, respectively. Mean MEPS was 90 (range, 70-100), and elbow performance was excellent in 4 patients, good in 4 patients, and fair in 1 patient. Mean DASH score was 21.9 (range, 0-61). Flexion contracture, forearm rotation arc, and MEPS score were better and the complication rate was lower in group A compared with group B. Centering of the stem was observed on both anteroposterior and lateral radiographs in 6 patients. Lucent lines around the prostheses, stress shielding under the neck of the radius, and ectopic ossification occurred in 5 patients. Three patients had osteoarthritis. Elbow stiffness and ulnar impaction syndrome occurred in 2 patients but only after placement of a secondary RHP. Satisfactory outcomes were obtained using a metallic press-fit RHP for nonreconstructible radial head fractures. [Orthopedics. 2019; 42(6):e545-e551.].

High Risk of Further Surgery After Radial Head Replacement for Unstable Fractures: Longer-term Outcomes at a Minimum Follow-up of 8 Years

BACKGROUND

The evidence for treating acute, unreconstructable radial head fractures in unstable elbows with radial head replacement predominantly consists of short- to mid-term follow-up studies with a heterogenous mix of implants and operative techniques. Data on longer-term patient-reported outcomes after radial head replacement is lacking.

QUESTIONS/PURPOSES

(1) What proportion of patients undergo revision or implant removal after radial head replacement? (2) At a minimum of 8 years follow-up, what are the patient-reported outcomes (QuickDASH, Oxford Elbow Score, and EuroQol-5D)? (3) What factors are associated with a superior long-term patient-reported outcome, according to the QuickDASH?

METHODS

Between September 1994 and September 2010, we surgically treated 157 patients for acute radial head fractures. We excluded patients where the radial head was excised (n = 21), internally fixed (n = 15), or replaced as a secondary procedure after failed internal fixation (n = 2). A total of 119 patients who underwent radial head replacement surgery for an acute unreconstructable fracture were included, with a mean age of 50 years (range 15 to 93 ± 19 years), and 53% of patients (63) were women. All but two implants were uncemented, loose-fitting, monopolar prostheses, of which 86% (102) were metallic and 14% (17) were silastic. Implants were only cemented if they appeared unstable within the proximal radius. Silastic implants were used in the earlier series and replaced by metallic implants starting in 2000. We reviewed electronic records to document postoperative complications and prosthesis revision and removal. A member of the local research team (THC, CDC) who was not previously involved in patient care contacted patients to confirm complications, reoperations and to obtain long-term patient-reported outcomes scores. Nineteen patients had died at the point of outcome score collection. Of the remaining 100 patients, 80 were contacted (67% of total cohort), at a median of 11 years (range 8 to 24 years) after injury. The primary outcome measure was the QuickDASH score.

RESULTS

Of 119 patients, 25% (30) underwent reoperation, with three patients undergoing revision and 27 patients undergoing prosthesis removal at a median of 7 months (range 0 to 125 months). Twenty-one of 30 procedures (70%) occurred within 1 year after implantation. Kaplan-Meier survivorship analysis demonstrated a cumulative implant survival rate of 71%. In the 80 patients contacted, the mean QuickDASH score was 13 ± 14, the mean Oxford Elbow Score was 43 ± 6, and the median EuroQol-5D score was 0.8 (-0.3 to 1.0). After controlling for covariates, we found that prothesis revision or removal (p = 0.466) and prosthesis type (p = 0.553) were not associated with patient-reported outcome, according to the QuickDASH.

CONCLUSIONS

The management of acute unreconstructable fractures of the radial head in unstable elbow injuries with radial head replacement has a high risk of reoperation. Patients must be counselled regarding this risk of secondary intervention, of which the peak risk appears to be within 1 year after implantation. Despite this, patients report low disability according to the QuickDASH at a minimum follow-up of 8 years.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Joint contact areas after radial head arthroplasty: a comparative study of 3 prostheses

BACKGROUND

Contact stresses of radial head prostheses remain a concern, potentially leading to early capitellar cartilage wear and erosion. In particular, point contact or edge loading could have a detrimental effect. The purpose of this study was to compare 3 different types of radial head prostheses in terms of joint contact areas with each other and with the native situation. The hypothesis was that the joint contact areas would be lower after monopolar arthroplasty.

METHODS

Seven fresh-frozen cadaveric upper limbs were used. Radiocapitellar contact areas of a monopolar design, a straight-neck bipolar design, and an angled-neck bipolar design were compared with each other and with the native joint. After standardized preparation, polysiloxane was injected into the loaded radiocapitellar joint to create a cast from which the joint contact area was measured. Measurements were performed at 3 angles of elbow flexion and in 3 different forearm positions.

RESULTS

In the native elbow, contact areas were highest in supination. Elbow flexion had no significant effect on native and prosthetic joint contact areas. Contact areas were decreased for all types of arthroplasties compared with the native joint (from 11% to 53%). No significant contact area difference was found between the 3 designs. However, bipolar prostheses showed lateral subluxation in neutral forearm rotation, resulting in a significant decrease in the contact areas from pronation to the neutral position.

CONCLUSIONS

All types of radial head prostheses tested showed a significant decrease in radiocapitellar contact area compared with the native joint. Bipolar designs led to subluxation of the radial head, further decreasing radiocapitellar contact.

Antibacterial coating of implants: are we missing something?

Implant-related infection is one of the leading reasons for failure in orthopaedics and trauma, and results in high social and economic costs. Various antibacterial coating technologies have proven to be safe and effective both in preclinical and clinical studies, with post-surgical implant-related infections reduced by 90% in some cases, depending on the type of coating and experimental setup used. Economic assessment may enable the cost-to-benefit profile of any given antibacterial coating to be defined, based on the expected infection rate with and without the coating, the cost of the infection management, and the cost of the coating. After reviewing the latest evidence on the available antibacterial coatings, we quantified the impact caused by delaying their large-scale application. Considering only joint arthroplasties, our calculations indicated that for an antibacterial coating, with a final user's cost price of €600 and able to reduce post-surgical infection by 80%, each year of delay to its large-scale application would cause an estimated 35 200 new cases of post-surgical infection in Europe, equating to additional hospital costs of approximately €440 million per year. An adequate reimbursement policy for antibacterial coatings may benefit patients, healthcare systems, and related research, as could faster and more affordable regulatory pathways for the technologies still in the pipeline. This could significantly reduce the social and economic burden of implant-related infections in orthopaedics and trauma. Cite this article: C. L. Romanò, H. Tsuchiya, I. Morelli, A. G. Battaglia, L. Drago. Antibacterial coating of implants: are we missing something? Bone Joint Res 2019;8:199-206. DOI: 10.1302/2046-3758.85.BJR-2018-0316.

Failure of Adjustably Aligned Modular Radial Head Arthroplasty With Head-Neck Dissociation and Metallosis

Radial head arthroplasty was introduced in 1941 and the literature supports satisfactory overall midterm patient outcomes and acceptable complication profiles with several models. There are several previously described mechanisms by which radial head complications typically occur. We present the case of a rarely described mechanism of radial head implant failure: elbow synovitis and pain from partial dissociation and metallosis in an adjustably aligned, modular, monopolar, mixed metal, press-fit radial head arthroplasty.

Clinical outcomes of anconeus interposition arthroplasty after radial head resection in native and prosthetic radial heads

BACKGROUND

Radiocapitellar pathology after traumatic injury to the elbow can be challenging to treat. The anconeus interposition arthroplasty has been proposed to treat radiocapitellar or proximal radioulnar joint dysfunction and pain, or both. This study evaluated whether radial head excision (native or prosthetic), followed by an anconeus interposition arthroplasty, relieves pain and improves subjective and objective elbow function in patients with post-traumatic radiocapitellar pathology.

METHODS

A retrospective comparative case series was performed of 50 consecutive patients who underwent a native radial head excision or radial head implant excision, followed by an anconeus interposition arthroplasty. Clinical outcome scores, range of motion, and proximal radius migration were evaluated in patients with at least 2 years of follow-up.

RESULTS

Included were 23 patients (11 native and 12 prosthetic radial heads) with a mean age of 41 years. Average follow-up was 38 months. Overall, significant improvement was obtained in the Disabilities of the Arm, Shoulder and Hand and visual analog scale scores. Range of motion significantly improved from preoperatively to postoperatively. Patients with a native radial head excision scored better on the Single Assessment Numeric Evaluation (76.8 vs. 56.3, P = .037) and obtained significantly more flexion postoperatively (141° vs. 123°, P = .016). Mild wrist pain developed in 3 patients, but no further intervention was required. The overall complication rate was 13%, and 5 patients required reoperation.

CONCLUSIONS

Anconeus interposition arthroplasty performed after radial head resection in native and prosthetic groups is a viable adjunct in the operative treatment of patients with post-traumatic radiocapitellar pathology. However, whether anconeus interposition arthroplasty alone produced the favorable clinical results of this study was difficult to determine.