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

Loose-fit vs. press-fit stems and risk for surgical reintervention following radial head arthroplasty: a US-based cohort study of 1575 patients

BACKGROUND

Radial head arthroplasty (RHA) is performed with increasing frequency for reconstruction of comminuted radial head fractures. Implants can be categorized by stem design, either loose fit or press fit. Currently, the RHA literature does not suggest one implant type is superior to another based on revision and reoperation rates, although most RHA outcome studies have small numbers of patients with few events to detect a difference. This study evaluated the association between stem design and risk of revision and reoperation after RHA.

METHODS

A total of 1575 patients aged ≥18 years who underwent primary RHA within a US-based health care system were identified (2009-2021). Revision following the index RHA was the primary outcome of interest; ipsilateral reoperation was a secondary outcome. Multivariable Cox proportional hazard regression was used to evaluate the risk of outcomes by loose vs. press fit with the adjustment for race and ethnicity, American Society of Anesthesiologists classification, region, surgeon RHA volume, and simultaneous ipsilateral extremity procedures.

RESULTS

Of the 1575 RHAs, 681 (43.2%) received a loose-fit stem. The cumulative revision probability was 2.6% for loose fit and 3.5% for press fit. In adjusted analysis, we did not observe a difference in risk of revision (hazard ratio [HR] = 0.78, 95% confidence interval [CI] = 0.41-1.46) or reoperation (HR = 0.73, 95% CI = 0.43-1.25). Additionally, there were no observed differences in risk of revision (HR = 0.62, 95% CI = 0.28-1.38) or reoperation (HR = 0.90, 95% CI = 0.48-1.71) in the patient subgroup who underwent additional procedures in the same extremity at the time of RHA.

CONCLUSION

In this large multicenter cohort of 1575 primary RHAs, we did not observe a difference in risk of revision or reoperation following RHA based on stem design. The choice between using an implant with a loose- or press-fit stem may be based more on surgeon familiarity, implant availability, cost, and ease of use.

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.

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.

Monobloc vs. Modular Radial-Head Arthroplasty for Complex Elbow Trauma: Long-Term Follow-Up and Comparative Evaluation

Introduction: Mason Type 3 radial-head fractures are typically treated with open reduction and internal fixation (ORIF) or radial-head arthroplasty (RHA). Prosthetic options include traditional monobloc implants and newer modular implants designed to match patient anatomy. While short- and medium-term outcomes of metallic RHA are generally favorable, this study aims to compare the long-term outcomes of patients treated with monobloc versus modular implants. Methods: The medical records of all the patients who underwent RHA at a level I trauma center between 2000 and 2011 were retrospectively reviewed. Patients who were available for follow-up were invited for reassessment, which included physical examination, questionnaires for the assessment of elbow pain and function, and follow-up radiographs. Results: Out of 35 patients who had RHA, 13 (37%) had a monobloc prosthesis and 22 (63%) had a modular prosthesis. Out of the patients that could be traced, 4 patients from the monobloc group and 10 patients from the modular group agreed to participate in the study. The mean follow-up time was 15 years in the monobloc group and 12.4 years in the modular group. Patients in the modular group demonstrated superior functional outcomes compared to the monobloc group, with statistically significant improvements in MEPS and DASH scores and a non-significant trend towards better ASES scores and VAS scores. Physical examination revealed a decline in function in the operated arm for both groups, with statistically significant differences favoring the modular group in elbow flexion and extension. Radiographic analysis showed varying degrees of implant loosening, with the modular group exhibiting less loosening compared to the monobloc group. Mild degenerative changes and heterotopic ossification were also observed, predominantly in the modular group. Conclusions: The results suggest that modular implants offer superior functional outcomes compared to monobloc implants. The modular group showed statistically significant improvements in elbow flexion and extension. These findings indicate that modular implants may be a more favorable option for enhancing patient outcomes. Further research with larger sample sizes is recommended to confirm these trends and to better understand the long-term benefits of modular implants.

The impact of anatomic alignment on radiocapitellar pressure following radial head arthroplasty

BACKGROUND

The incidence of radial head fractures is increasing, and radial head arthroplasty (RHA) is being more frequently used as treatment for irreparable fractures. Our objective was to compare radiocapitellar pressure between the native joint and 2 radial head prosthesis conditions: (1) a prosthetic head that was aligned to the forearm axis of rotation and (2) the same prosthesis with an axisymmetric nonaligned head.

METHODS

Ten cadaveric specimens received a pressfit radial head prosthesis (Align; Skeletal Dynamics) for both prosthetic testing conditions. Anatomic alignment (AL) was defined as the prosthetic head aligned to the forearm axis of rotation. Axisymmetric alignment (AX) was defined as the prosthetic radial head aligned to the axis of the prosthetic stem. Axial load was applied with the elbow in extension and the forearm pronated. Data were collected using a Tekscan 4000 sensor.

RESULTS

The mean pressure in the AL and AX groups were significantly higher than the mean pressure in the native joint. Compared with the native joint, the mean pressure was 19% higher in the AL group and 56% higher in the AX group. Peak pressure beyond 5 MPa occurred in 0 specimens in the native joint group, in 1 specimen (10%) in the AL group, and in 5 specimens (50%) in the AX group.

DISCUSSION

Our results demonstrated that a pressfit radial head prosthesis aligned with the forearm axis of rotation yields capitellar pressures that were more similar to the native condition than a nonaligned pressfit prosthesis. These findings suggest that anatomic alignment may optimize capitellar wear properties, improving the long-term durability of radial head arthroplasty.

Update on elbow arthroplasties with emphasis on imaging

Elbow arthroplasty is increasing in popularity and can be used to treat many conditions, such as trauma, primary and secondary osteoarthritis, inflammatory arthritis, and osteonecrosis. Total elbow arthroplasty (TEA) is reserved for patients with severe symptoms refractory to more conservative management. In addition to TEA, hemi-arthroplasty, interposition arthroplasty, and resection arthroplasty also play roles in the management of elbow pain. There are specific indications for each type of arthroplasty. Postoperative complications may occur with elbow arthroplasties and may be surgery or hardware related. Imaging is important in both pre-operative planning as well as in post-surgical follow-up. This article reviews the different types of elbow arthroplasties, their indications, their normal postoperative imaging appearances, and imaging findings of potential complications.

Radial head replacement for acute complex elbow instability: a long-term comparative cohort study of 2 implant designs

BACKGROUND

Radial head fractures not amenable to reconstruction should be treated by radial head replacement (RHR) when there is associated elbow or forearm instability. There are multiple RHR designs with different philosophies, but 2 of the most commonly used implants include the anatomic press-fit radial head system and the loose-fit metallic spacer. There is little information available specifically comparing the long-term clinical and radiographic outcomes of these 2 systems. The objective of this study was to compare the long-term clinical and radiologic outcomes of 2 RHR designs in the context of complex acute elbow instability.

MATERIALS AND METHODS

Ninety-five patients with an average age of 54 years (range, 21-87 years) underwent an acute RHR (46 press-fit Acumed anatomic and 49 loose-fit Evolve metallic spacer) and were prospectively followed for an average of 61 months (range, 24-157 months). There were 34 terrible triads; 36 isolated RH fractures with medial, lateral, or longitudinal instability; and 25 RH fractures associated with a proximal ulnar fracture. Clinical outcome and disability were evaluated with the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score, and the Disabilities of the Arm, Shoulder, and Hand (DASH) score. Pain and satisfaction were assessed using a visual analog scale. Radiographic analysis included presence of loosening, bone loss, and overstuffing related to the RHR.

RESULTS

Eight patients with an anatomic RHR (2 with overstuffing, 3 for stiffness, and 3 with loose implants) and 1 patient with a spacer (with stiffness) required implant removal. There were no significant differences between spacer RHR and anatomic RHR in arc of motion (120° vs. 113°, P = .14), pain relief (1 vs. 1.7, P = .135), MEPS (94 vs. 88; P = .07), Oxford Elbow Score (42.3 vs. 42.2, P = .4), or DASH score (12.2 vs. 14.4, P = .5). However, patients with a spacer RHR were significantly more satisfied (9 vs. 7.7; P = .004) than those with an anatomic implant. Radiographically, 19 anatomic implants had significant proximal bone loss and 10 showed complete lucent lines around the stem. Lucent lines were common around the spacer RHR. These radiographic changes were not always related to worse clinical outcomes.

CONCLUSION

Both the anatomic and spacer RHR designs can provide good clinical long-term outcomes. However, patients with a spacer showed a higher degree of satisfaction and those with an anatomic press-fit RHR had a higher revision rate, with radiographic changes that warrant continued follow-up.

90-day outcomes and factors for complications following radial head arthroplasty for Mason Type III and IV radial head fractures

PURPOSE

The aim of this study is to evaluate 90-day outcomes and complications following radial head arthroplasty (RHA) for Mason Type III and IV radial head fractures (RHFs) and determine factors predisposing patients to early complications and revision surgery.

METHODS

Patients undergoing RHA for Mason Type III and IV RHFs were identified retrospectively from an institutional database. Postoperative complications, reoperations, elbow range of motion, radiographs and concomitant injuries on the ipsilateral upper extremity were reviewed. Additionally, injuries were sub-classified as low-energy trauma (LET) or high-energy trauma (HET). Univariate logistic regression was performed to evaluate the risk for complications using patient factors not limited to the presence of concomitant ligamentous or bony injuries. P values < 0.05 were considered statistically significant.

RESULTS

Seventy four patients were included in our study with an average follow-up time of 12.7 months. Complications within 90-days of operation occurred in 8.1% of patients: heterotopic ossification (4.1%), superficial wound dehiscence (2.7%), and posterior interosseous nerve palsy (1.4%). No patients required readmission or revision surgery in the 90-day postoperative period. Univariate regression analysis did not demonstrate a significant association between diabetes, ASA status, HET versus LET, or the presence of concomitant injury. Concomitant injuries were found in 92% of patients.

CONCLUSION

Radial head arthroplasty for RHFs demonstrates a low complication rate in the short-term. Diabetes, ASA class, high versus low energy trauma, and presence of concomitant injury were not found to be associated with higher complication rates in the 90-day postoperative period.

LEVEL OF EVIDENCE

Level of evidence IV, retrospective case series.

Clinical and radiological outcome of Mason-Johnston types III and IV radial head fractures treated by an on-table reconstruction

Background

Only few methods treating comminuted radial head fractures have been established providing sufficient joint reconstruction, restoring radial length and enabling early joint mobilization. When an anatomical reconstruction using open reduction and internal fixation is not possible, radial head resection or primary arthroplasty is often conducted. An “Ex situ/on-table” reconstruction is widely disregarded but can be an option. The purpose of this study was to evaluate the functional and radiological outcome of comminuted radial head fractures treated with an “on-table” reconstruction and internal fixation using a low profile plate.

Methods

Fourteen patients who sustained a radial head fracture (9 Mason-Johnston type III and 5 Mason-Johnston type IV) and were treated with an “on-table” reconstruction between 2010 and 2020 were evaluated retrospectively. The patients mean age was 41.3 years (range 21–69). The clinical evaluation included active range of motion, grip strength, pain level and elbow stability. The functional outcome was assessed using the Disability of Arm, Shoulder and the Hand (DASH) score, Mayo Elbow Performance Index (MEPI), Broberg and Morrey score. The radiological examination included a.p. and lateral views of the injured elbow to evaluate nonunions, loss of reduction, joint alignment, avascular radial head necrosis, heterotopic ossifications and posttraumatic osteoarthritis.

Results

The inclusion rate was 74% with a mean follow-up of 50 months (range 16–128). The mean elbow flexion of the injured side was 126° (range110–145°) with an average extension loss of 8° (range 0–40°). Pronation was 65° (15–90°) and supination 66° (5–90°). The mean MEPI was 87 points (range 45–100). The mean DASH score was 13 points (range 1–88). According to the Broberg and Morrey functional scoring system, the average score was 92 points (range 88–100). Complete bone union was achieved in 9 cases, partial union in 4 cases and nonunion in one case. There were no signs of avascular necrosis of the radial head. Signs of post-traumatic osteoarthritis were seen in 11 cases. Five patients needed an implant removal due to a radio-ulnar impingement and one patient a revision surgery due to the nonunion and implant breakage.

Conclusions

An on-table (ex situ) reconstruction of the radial head is a reliable option with a good clinical outcome and low complication rate in the surgical treatment of comminuted radial head fractures. It can restore joint alignment and maintain radial length. The risk for avascular necrosis is neglectable, and the bone healing rate is high.