Radial Head Replacement for Acute Radial Head Fractures: Outcome and Survival of Three Implant Designs With and Without Cement Fixation

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.

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.

[Radial Head Replacement: Management of Elbow and Forearm Instability after Comminuted Radial Head Fractures Associated with Elbow Dislocation]

PURPOSE OF THE STUDY

This manuscript aims to identify an indication algorithm for the surgical treatment of radial head fractures associated with elbow dislocation. The study compares the mid-term functional outcomes of patients with multifragment radial head fracture treated by resection with the outcomes of patients treated with radial head replacement.

MATERIAL AND METHODS

The cohort of 34 patients who sustained a radial head fracture at the mean age of 42.5 years (age range 20-81 years) was broken down into two groups by type of surgery. The EXT group consists of 20 patients with the radial head fracture treated by radial head resection. The END group includes 14 patients treated with the radial head replacement. In all patients, the radial head fracture was associated with elbow dislocation (type IV fracture according to the Mason-Johnston classification). The modified Kocher's surgical approach was used in all patients of both the groups. In the EXT group, resection of the fragmented radial head was performed. In the END group, the ExploR® Modular Radial Head System (Zimmer, Biomet, USA) was used, consisting of a CoCr (cobalt chromium) alloy head and a titanium stem. The pain and the range of motion of the elbow and forearm were evaluated after the completion of the outpatient rehabilitation (the mean follow-up period was 2.4 years). Simultaneously, the elbow joint stability was assessed. Radiographs were taken to detect heterotopic ossifications, proximalization of the radius, and any signs of prosthesis loosening. The frequency of reoperations was followed-up. The MEPS (Mayo Elbow Performance Score) was calculated.

RESULTS

In the EXT group, the mean elbow flexion was 117.5° and the mean pronation/supination was 166.9°. In 50% of patients, the MEPS obtained was greater than 90 points, which means an excellent functional outcome. In 1 patient (5%), recurrent elbow dislocation occurred which was the reason for revision surgery (elbow transfixation with the Kirschner wires and medial collateral ligament suture). Revision surgery was also performed in 2 patients (10%) in whom not all the radial head fragments were removed. Moreover, also observed was elbow joint instability (2 patients) and temporary radial nerve paralysis (1 patient). In 1 case discrete proximalization of the radius developed. The patients in the END group showed the mean elbow flexion of 112° and the mean pronation/supination of 135°. The MEPS obtained from 69% of patients was greater than 90 points, which means an excellent outcome. The pain under load was reported by 3 patients (21%). In 5 patients (35%), the X-rays showed radiolucent zone around the stem of the prosthesis. Neither revision surgery, nor prosthesis removal has been performed yet in any patient. No instability, neurological complications or infections have been reported. In both EXT and END group heterotopic ossifications have developed in 4 patients.

CONCLUSIONS

Radial head replacement compared to the radial head resection in the management of multifragment fractures associated with elbow dislocations increase the elbow and forearm stability. The group of patients with an implanted radial head prosthesis shows a higher percentage of patients achieving excellent functional outcome than the group of patients with radial head resection.

KEY WORDS

radial head, elbow, fracture, dislocation, resection, prosthesis.

Radial head replacement with the 3D-printed patient-specific titanium prosthesis: Preliminary results of a multi-centric prospective study

PURPOSE

To report preliminary clinical results and safety of 3D-printed patient-specific titanium radial head (RH) prosthesis in treatment of the irreparable RH fractures.

MATERIAL AND METHODS

This multi-centric prospective study included 10 patients (6 men and four women, mean age 41 years (range, 25-64 years)). Three cases were classified as Mason type III and 7 cases as type IV. Patients were assessed preoperatively, intraoperatively, and at 1, 6, 12, 24, 36, and 48 weeks postoperatively. Range of motion (ROM), visual analog scale (VAS) score, Disabilities of the Arm, Shoulder and Hand (DASH) score, Mayo Elbow Performance Score (MEPS), radiology imaging, and laboratory blood and urine testing were evaluated.

RESULTS

The prostheses were implanted utilizing cemented stems in 5 patients and cementless stems in 5 patients. Intraoperatively, well congruency of a prosthesis with capitellum and radial notch of ulna was observed in all cases. All patients had improvement of ROM, VAS score, DASH score, and MEPS during the postoperative follow-ups. At the final follow-up, mean elbow extension was 6.5° (range, 0°-30°), flexion 145° (range, 125°-150°), supination 79° (range, 70°-80°), and pronation 73.5° (range, 45°-80°). Mean VAS score was 0.3 (range, 0-3), DASH score was 12.35 (range, 1.7-23.3), and MEPS was 99.5 (range, 95-100). Postoperative radiographs demonstrated heterotopic ossification in 2 cases, periprosthetic radiolucency in 2 cases, and proximal radial neck resorption in 2 cases. No one had the evidence of capitellar erosion, implant failure, malpositioning, overstuffing, or symptomatic stem loosening. There was no significant alteration of laboratory results or adverse events related to the 3D-printed prosthesis implantation.

CONCLUSION

The preliminary results demonstrated that implantation of the 3D-printed patient-specific titanium RH prosthesis is safe and may be a potential treatment option for irreparable RH fracture.

Prognostic Factors of Function in Nonoperatively Treated Radial Head Fractures: A Prospective Cohort Study

OBJECTIVES

To identify patient-related factors and fracture characteristics influencing the functional outcomes of nonoperatively treated radial head fractures and to determine function at 1 year.

DESIGN

Prospective cohort study.

SETTING

Academic Level 1 trauma center.

PATIENTS/PARTICIPANTS

Consecutive isolated radial head fractures fitting the inclusion criteria between May 2013 and July 2016.

INTERVENTION

Nonoperative treatment of isolated radial head fractures.

OUTCOME MEASUREMENTS

Logistic regressions between potential prognostic factors and function assessed with the Mayo Elbow Performance Score (MEPS), the Disabilities of the Arm, Shoulder, and Hand (DASH) score, and range of motion at 1.5-3-6-12 months.

RESULTS

One hundred fourteen patients were included (78% Mason I [OTA/AO 2R1B1], 20% Mason II [OTA/AO 2R1B3], and 2% Mason III [OTA/AO 2R1C3]). Mean MEPS and DASH score at the last follow-up were excellent [96.4 ± 7.6 and 3.7 ± 8.6] with, respectively, 79.8% and 92.7% of satisfactory results. Depressive symptoms at injury baseline (Quick Inventory of Depressive Symptomatology > 5) are a constant predictor of unsatisfactory function (MEPS <90 or DASH >17]). Older age and female sex were all linked to worse function at the first follow-ups ( P < 0.05), whereas lower socioeconomic class and receiving financial compensations were associated to unsatisfactory function at 1 year ( P < 0.05).

CONCLUSIONS

Although most nonoperatively treated radial head fractures heal with excellent function, some patients still exhibit unsatisfactory results at 1 year. Symptoms of depression at injury baseline are a constant and significant predictor of unsatisfactory function. Early detection of depressive symptoms would allow for interventions that may optimize function.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

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.

Radial head replacement - A comprehensive review

Background

Radial head fractures represent 1-4% of all adult fractures and 1/3rd of elbow fractures (Kaas et al., 2010). Radial head is an important secondary stabilier of the elbow. The aim of the treatment of radial head fractures is to achieve stability and good functional outcome. Radial head replacement (RHR) is indicated when robust reconstruction and fixation of the fracture fragments is not possible.

Methods

This article explores history and evolution, anatomical considerations, biomechanics, implant designs, indications, surgical outcomes and controversies in radial head replacement based on current evidence.

Results

There is a wide range of RHR designs available without conclusive evidence to support the superiority of one design over the other. Ranges of motion, functional outcomes and complication were comparable among different designs with a high incidence of complications reported in many studies.

Conclusion

RHR remains a good option in unreconstructible radial head fractures, with potential to regain excellent function. It is imperative to continue with the quest to innovate and improve on current designs, to reduce complications in the long term.

Acute versus delayed radial head arthroplasty for the treatment of radial head fractures

BACKGROUND

Radial head arthroplasty (RHA) is an important tool in the acute treatment of comminuted radial head and neck fractures. RHA is also performed in a delayed manner after failed open reduction and internal fixation, for fracture malunion or nonunion, and other chronic post-traumatic elbow disorders where restoration of the lateral column of the elbow is considered necessary. The relative efficacy and longevity of acute vs. delayed RHA is unknown. We sought to compare clinical, radiographic, and patient-reported outcomes between these groups.

METHODS

We identified patients ≥18 years old who underwent an RHA between 2000 and 2018 and then extracted 135 total elbows with a mean follow-up of 2.3 years that sustained isolated radial head fractures (30%), terrible triad injuries (66%), or Essex-Lopresti injuries (4%). The acute cohort (RHA: <12 weeks) contained 101 elbows that underwent surgery at a mean of 0.6 weeks (range, 0 days to 7 weeks, 96% <2 weeks) from injury, whereas the delayed cohort (RHA: 12 weeks to 2 years) contained 34 elbows that underwent surgery at a mean of 36 weeks (range, 14-82 weeks) from injury. Patients in the acute group had a higher percentage of terrible triad injuries (75% vs. 40%, P < .001) and Mason 3 fractures (98% vs. 45%, P < .001).

RESULTS

At the final follow-up, 13 of 101 patients in the acute cohort (13%) and 7 of 34 patients in the delayed cohort (21%) required implant revision or resection. A total of 25 patients (25%) in the acute cohort and 12 patients (35%) in the delayed cohort required a reoperation. Kaplan-Meier 2-year survival estimates free of implant resection or revision (90% acute, 86% delayed) and reoperation (76% acute, 70% delayed) were similar between groups. In patients with 5-year follow-up, there was an increased rate of revision or resection in the delayed group (30% vs. 13%). Two-year survival estimates free of radiographic loosening were 80% in the acute cohort vs. 57% in the delayed cohort (P = .04). Mayo Elbow Performance Score at 2 years demonstrated mean scores of 83 and 79 in the acute and delayed groups, respectively, with 71% of the acute cohort and 64% of the delayed cohort achieving good or excellent scores.

CONCLUSIONS

Our results demonstrated that although 2-year Kaplan-Meier survival free of revision or resection estimates and reoperation rates was equivalent between the groups, the delayed group experienced worse Mayo Elbow Performance Score outcomes, a higher revision or resection rate at 5 years, and an increased rate of radiographic loosening.

[Radial head prosthesis for acute fractures]

Non-reconstructible radial head fractures with concomitant injuries and resultant instability of the elbow are often treated by implantation of a radial head prosthesis. Various prosthetic designs and implantation techniques are available. Several pitfalls have to be respected during implantation. This article provides tips and tricks for successful implantation and aftercare and gives an overview of long-term outcomes and revision rates.

Does stress shielding after radial head arthroplasty affect functional outcomes?

BACKGROUND

Various complications related to the prosthesis, such as implant loosening and stress shielding phenomenon, could develop after prosthetic replacement of the radial head. Stress shielding is known to occur around rigidly fixed implants. The purpose of this study was to evaluate the clinical influence and causative factors of the stress shielding phenomenon after radial head arthroplasty (RHA).

METHODS

Clinical records and radiographs of 56 patients with unreconstructable radial head fractures who received radial head replacement between 2009 and 2019 were reviewed. Exclusion criteria were infection, loosening, and follow-up of less than 24 months. After exclusion, 35 patients were enrolled. Patients were divided into two groups: an anatomical press-fit group (Anatomical Radial Head System; Acumed, Hillsboro, OR, USA) and a round bipolar cemented group (RHS; Tornier, Montbonnot Saint-Martin, France). Stress shielding around the prosthesis was assessed in the serial radiological examination. Clinical results were assessed using Mayo elbow performance score (MEPS), Quick Disabilities of the Arm, Shoulder, and Hand (q-DASH) score, range of motion (flexion-extension arc and pronation-supination arc), and visual analog scale score (VAS). Correlations between stress shielding phenomenon and demographic data and functional results were analyzed.

RESULTS

At an average follow-up of 43.06 (± 14.6) months, 14 (40%) out of 35 fixed stems demonstrated stress shielding. Our results showed that the rate of stress shielding was significantly higher in cases with a bilateral ligament injury and in the anatomical press-fit group (p = 0.028 and p = 0.0091, respectively). However, stress shielding around prostheses did not affect the clinical results (p > 0.05).

CONCLUSION

The stress shielding phenomenon around radial head prosthesis may vary according to prosthetic design and severity of ligament injuries. Stress shielding does not affect the mid-term outcomes in the treatment of acute fractures of the radial head.

LEVEL OF EVIDENCE III

Retrospective Cohort Comparison; Treatment Study.