Radial head fractures

A proposal for computed tomography-based algorithm for the management of radial head and neck fractures: the Proximal and Articular Radial fractures Management (PARMa) classification

Background

Owing to the great variety of fracture patterns and limitations of the standard radiographic investigation, all the already available classification systems for radial head and neck fractures (RHNFs) are limited by a poor-to-moderate degree of intraobserver and interobserver reliability. Although computed tomography (CT) is being increasingly used to better understand the fracture characteristics, a CT-based classification system of RHNFs is still lacking. Therefore, in this agreement study, we aimed to propose a classification system based on two-dimensional and three-dimensional (2D/3D) CT to test the hypothesis that this classification has good intraobserver and interobserver reliability. We have also provided a treatment algorithm.

Methods

Our proposed classification-Proximal and Articular Radial fractures Management (PARMa)-is based on 2D/3D CT imaging. It is divided into four types based on different fractures patterns. The 2D/3D scans of 90 RHNFs were evaluated in a blinded fashion by eight orthopedic and one radiology consultant, according to the proposed classification. The first phase of observation aimed to estimate the interobserver agreement. The second phase involved a new observation, 4 weeks after the first analysis, and estimated the intraobserver reliability. The standard radiographs of these 90 fractures were also evaluated by the same observers, with the same timing and methods, based on the same classification. Cohen's Kappa was applied for intraobserver agreement. Fleiss's Kappa was used both within and among the evaluators. Kendall's coefficient of concordance was employed to determine the strength of association among the appraisers' rankings. Furthermore, Krippendorff's alpha was chosen as an adjunctive analysis to assess between evaluators' agreement.

Results

For the intraobserver agreement, Fleiss' Kappa statistics confirmed the consistency (overall kappa values: 0.70-0.82). Cohen's Kappa statistics aligned with Fleiss' Kappa, with similar kappa values and significant P values (P < .001). For interobserver agreement, Fleiss' Kappa statistics for between appraisers showed moderate-to-substantial agreement, with kappa values ranging from 0.54 to 0.82 for different responses. The results relating to the appraisers' observation of standard radiographs showed that the overall Fleiss' Kappa values for intraobserver agreement ranged from 0.34 to 0.82, whereas Fleiss' Kappa statistics for interobserver agreement ranged from 0.40 to 0.69.

Conclusions

The proposed classification system is expected to be reliable, reproducible, and useful for preoperative planning and surgical management. Both 2D and 3D CT allow the identification of the magnitude and position of displacement and articular surface involvement.

Trends in treatment and epidemiology of radial head fractures

Objective

We aimed to assess the recent trends in the demographics of radial head and neck fractures and their management based on displacement.

Methods

TriNetX was queried for cases from 1 January 2017, through 31 December 2022. ICD diagnosis codes were used to define patient cohorts with radial head or neck fractures. CPT codes were searched to determine the operative patient cohorts. All cases not included under any CPT codes were defined as the nonoperative cohort.

Results

A total of 103,432 patients were included. The female-to-male ratio was 4:3. The average age of individuals with radial head fractures was 43 ± 25 years, with a greater age in the replacement cohort compared to the fixation group. The incidence rates of displaced and nondisplaced fractures were similar across the years. Nonoperative management was overwhelmingly preferred over operative management. Regarding operative management, internal fixation rates were higher than replacement rates.

Conclusion

The trend of fracture incidence and the type of operative management has remained constant over the past 6 years. However, an increase in the number of radial head replacements is expected with an aging population. Moreover, radial head and neck fractures are among the benign injuries most frequently managed nonoperatively.

A Study Evaluating the Functional Outcomes of Mason Type III and IV Radial Head Fractures Treated With a Radial Head Prosthesis

Objective This research aimed to assess the functional result of type III and IV radial head fractures that were treated using a radial head prosthesis. Methods A retrospective investigation was conducted on 70 patients with type III and IV radial head and neck fractures, as classified by Mason. The patients were hospitalized and received treatment at the Orthopaedics Department, where they had radial head prosthesis surgery for three years. Results Among the total of 70 cases, 42 (60%) cases were below the age of 40, while 28 (47%) cases were over 40 years. The average age was 36.4 years. The maximum age recorded was 54 years, while the lowest age recorded was 30 years. The female population outnumbered the male population. The majority of instances (42, 60%) were attributed to falls, while the remaining cases were caused by road traffic accidents (RTAs). Out of the total 70 instances, 52 cases (74.28%) exhibited right-side dominance, whereas 18 cases (25.72%) exhibited left-side dominance. Within our case study group, 56 (80%) cases fell under modified Mason's classification type Ill, totaling 56 instances. The remaining 20% of the cases, amounting to 11 cases, were classified as modified Mason's classification type IV. Among the 70 patients, 55 cases (78.58%) did not have any ligamentous damage, whereas seven (10%) cases had lateral ulnar collateral ligament (LUCL) injury and eight (11%) cases had medial collateral ligament (MCL) injury. The P value for flexion, extension, pronation, and supination was shown to be very significant. Out of the total, 47 (67%) instances had an MEPI score (Mayo Elbow Performance Index) of more than 90, indicating exceptional performance. In addition, 16 cases (22.85%) had an MEPI score ranging from 75 to 89, which is considered a good result. Lastly, seven cases (10%) had an MEPI score ranging from 60 to 74, indicating a fair result. Conclusion The use of a radial head prosthesis is considered a viable option for managing severe and irreparable fractures of the radial head. Effective outcomes hinge on meticulous preoperative planning, skilled intraoperative techniques, and intensive postoperative rehabilitation. These elements collectively contribute to achieving consistent and favorable results in patients undergoing this surgical intervention.

[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.

Biomechanical comparison of different internal fixation devices for transversely unstable Mason type II radial head fractures

Background: The integrity of the radial head is critical to maintaining elbow joint stability. For radial head fractures requiring surgical treatment, headless compression cannulated screw fixation is a less invasive scheme that has fewer complications. The aim of this study was to compare the mechanical stability of different fixation devices, including headless compression cannulated screws and mini-T-plates, for the fixation of transversely unstable radial head fractures. Methods: Forty identical synthetic radius bones were used to construct transverse unstable radial head fracture models. Parallel, cross, and tripod headless compression cannulated screw fixation and mini-T plate fixation were applied. The structural stiffness of each group was compared by static shear loading. Afterward, cyclic loading was performed in each of the three directions of the radial head, and the shear stability of each group was compared by calculating the maximum radial head displacement at the end of the cycle. Findings: The mini-T plate group had the lowest structural stiffness (51.8 ± 7.7 N/mm) and the highest relative displacement of the radial head after cyclic loading (p < 0.05). The tripod headless compression cannulated screw group had the highest structural stiffness among all screw groups (p < 0.05). However, there was no significant difference in the relative displacement of the radial head between the screw groups after cyclic loading in different directions (p > 0.05). Interpretation: In conclusion, the biomechanical stability of the mini-T plate for fixation of transverse unstable radial head fractures is lower than that of headless compression cannulated screws. Tripod fixation provides more stable fixation than parallel and cross fixation with headless compression cannulated screws for the treatment of transversely unstable radial head fractures.