Prolonged dislocation and delay to surgery are associated with higher rates of heterotopic ossification in operatively treated terrible triad injuries

Reported outcome measures in complex fracture elbow dislocations: a systematic review

BACKGROUND

Complex elbow fracture dislocations, dislocation with fracture of one or several surrounding bony stabilizers, are difficult to manage and associated with poor outcomes. While many studies have explored treatment strategies but a lack of standardization of patient-reported outcome measures (PROMs) makes cross-study comparison difficult. In this systematic review, we aim to describe what injury patterns, measured outcomes, and associated complications are reported in the complex elbow fracture dislocation literature to provide outcome reporting recommendations that will facilitate improved future cross-study comparison.

METHODS

A systematic review was performed per Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. We queried PubMed/MEDLINE, Embase, Web of Science, and Cochrane databases to identify articles published between 2010 and 2022 reporting on adult patients who had a complex elbow fracture dislocation. Pathologic fractures were excluded. A bias assessment using the methodological index for nonrandomized studies criteria was conducted. For each article, patient demographics, injury pattern, outcome measures, and complications were recorded.

RESULTS

Ninety-one studies reporting on 3664 elbows (3654 patients) with an elbow fracture and dislocation (weighted mean age 44 years, follow-up of 30 months, 41% female) were evaluated. Of these, the injury pattern was described in 3378 elbows and included 2951 (87%) terrible triad injuries and 72 (2%) transolecranon fracture-dislocations. The three most commonly reported classification systems were: Mason classification for radial head fractures, Regan and Morrey coronoid classification for coronoid fractures, and O'Driscoll classification for coronoid fractures. Range of motion was reported in 87 (96%) studies with most reporting flexion (n = 70), extension (n = 62), pronation (n = 68), or supination (n = 67). Strength was reported in 11 (12%) studies. PROMs were reported in 83 (91%) studies with an average of 2.6 outcomes per study. There were 14 outcome scores including the Mayo Elbow Performance Score (n = 69 [83%]), the Disabilities of Arm, Shoulder and Hand (DASH) score (n = 28 [34%]), the visual analog scale for pain (n = 27 [33%]), QuickDASH score (n = 13 [15.7%]), and Oxford Elbow score (n = 5 [6.0%]). No significance was found between the number of PROMs used per article and the year of publication (P = .313), study type (P = .689), complex fracture pattern (P = .211), or number of elbows included (P = .152).

CONCLUSION

There is great heterogeneity in reported PROMs in the complex elbow fracture dislocation literature. Although there is no gold standard PROM for assessing complex elbow fracture dislocations, we recommend the use of at least the Mayo Elbow Performance Score and DASH outcomes measures as well as visual analog scale pain rating scale in future studies to facilitate cross-study comparisons.

The Internal Joint Stabilizer of the Elbow: A Systematic Review of the Clinical and Biomechanical Evidence

Purpose

The goal of surgical management for unstable elbow injuries is the restoration of joint concentricity and stability. After internal fixation, concerns may exist regarding instability or durability of the fixation construct. Historically, these scenarios were treated with options such as transarticular pinning or external fixation. Recently, an internal joint stabilizer (IJS) that allows postoperative mobilization was introduced. Our objective was to systematically review the literature to aggregate the clinical and biomechanical evidence for the IJS of the elbow.

Methods

A systematic review of the PubMed and Google Scholar databases was performed, following the PRISMA guidelines. The search results were narrowed from 2015 through 2023 to coincide with the inception of the device being reviewed.

Results

A total of nine retrospective reports on the IJS (N = 171) cases at a mean follow-up of 10.8 months were included. The pooled rate of implant failure was 4.4%, and recurrent instability was 4.1%. Additionally, the we included seven case reports and two biomechanical reports.

Conclusions

The aggregate literature describes satisfactory clinical outcomes with low rates of recurrent instability and device failure for the IJS of the elbow. The limited biomechanical investigations conclude efficacy for stability profiles.

Clinical relevance

Across a spectrum of unstable elbow cases, the IJS prevented recurrent instability during the early postoperative period. Notably, the device requires an additional procedure for removal, and the long-term impact of the retained devices is currently unclear.

The Incidence of Heterotopic Ossification in Surgically and Non-surgically Treated Elbow Fractures at a Municipal Hospital in Japan

Background: Heterotopic ossification (HO) is a well-recognised complication of after elbow trauma. The prevalence and risk factors of HO have been previously reported. However, these reports were based on elbow trauma that had undergone surgical treatment and most of them were from Western countries. This study aimed to assess the incidence of HO in patients with elbow fractures who were treated surgically and non-surgically in Japan. Methods: We retrospectively identified consecutive patients who were treated of elbow fractures and fracture-dislocations at our institution in recent consecutive 3-year periods. We extracted patient demographics, injury mechanisms and treatment details from the medical records. Furthermore, we reviewed radiographs to classify the fracture pattern and identify the presence or absence of HO. Results: HO was identified in 6/97 (6%) patients. Fracture-dislocation was noted in 4/6 patients. The fracture types with HO included terrible triad injury (n = 2), isolated coronoid process fractures (n = 2), distal humerus A-type fractures (n = 1) and radial head fracture (n = 1). According to the Hastings and Graham classification, HO was classified as Class I in five patients and Class II B in one patient who underwent additional surgery for HO resection. Conclusions: The incidence of HO was relatively low in our patients. However, of the 20 conservatively treated elbows, one patient developed clinically relevant HO and required excision of HO. Even patients with elbow fractures treated conservatively should be informed of the potential risk of developing severe HO requiring surgical excision. In addition, surgeons in this region could use these data to inform patients about the risk of HO development after an elbow injury. Level of Evidence: Level IV (Therapeutic).

Current concepts in the management of "Terrible Triad" injuries of the elbow

Terrible triad injuries of the elbow are complex injuries which can result in long term complications and significant disability. They must be identified correctly, and managed appropriately in order to maximise functional outcomes. A clear understanding of the bony and ligamentous anatomy is essential to plan appropriate surgical reconstruction to provide elbow stability. Urgent reduction of the elbow, followed by 3-dimensional imaging and surgical repair or replacement of the injured structures is the mainstay of treatment in the majority of cases. This review presents a summary of the relevant anatomy and the evidence for the management of these complex injuries.

Pathogenesis of acquired heterotopic ossification: Risk factors, cellular mechanisms, and therapeutic implications

Heterotopic ossification (HO), including hereditary and acquired HO, is the formation of extraskeletal bone in skeletal muscle and surrounding soft tissues. Acquired HO is often caused by range of motion, explosion injury, nerve injury or burns. Severe HO can lead to pain and limited joint activity, affecting functional rehabilitation and quality of life. Increasing evidence shows that inflammatory processes and mesenchymal stem cells (MSCs) can drive HO. However, explicit knowledge about the specific mechanisms that result in HO and related cell precursors is still limited. Moreover, there are no effective methods to prevent or reduce HO formation. In this review, we provide an update of known risk factors and relevant cellular origins for HO. In particular, we focus on the underlying mechanisms of MSCs in acquired HO, which follow the osteogenic program. We also discuss the latest therapeutic value and implications for acquired HO. Our review highlights the current gaps in knowledge regarding the pathogenesis of acquired HO and identifies potential targets for the prevention and treatment of HO.

Human osteoprogenitor cells obtained from traumatic heterotopic ossification samples showed enhanced osteogenic differentiation potential and ERK/Hedgehog signaling than that from normal bone

Traumatic heterotopic ossification (HO) refers to the abnormal ectopic osteogenesis following trauma, causing limb dysfunction and seriously lowering the life quality of patients. Aberrant osteogenic behavior of progenitor cells that ectopically accumulated within the soft tissues are believed to be responsible for HO formation. However, the detailed mechanism still remained to be clarified. Here in this study, we successfully isolated osteoprogenitors from human heterotopic ossification tissues (HO-ops) and identified their stemness and multi-directional differentiation potential. Using alkaline phosphatase staining together with alizarin red staining, we confirmed that the HO-ops in the heterotopic ossified tissues gained greater osteogenic potential than the normal human bone marrow mesenchymal stem cells (HBMSCs). RT-qPCR also indicated that HO-ops obtained more gene transcriptions of critical osteogenic determinators than HBMSCs. In addition, through Western blot, we proved that ERK signaling pathway and Hedgehog signaling pathway were significantly activated in the HO-ops. When U0126 and cyclopamine were used to inhibit ERK and hedgehog signaling respectively, the osteogenic potential of HO-ops decreased significantly. The hedgehog signaling and ERK signaling also showed cross-talk in HO-ops during osteogenic differentiation in HO-ops during osteogenic differentiation. The elevated ERK and hedgehog signaling was further confirmed in the human traumatic HO sample sections by immunohistochemical staining. In sum, our results showed that the activation of ERK and Hedgehog signaling pathway jointly enhanced the osteogenic potential of HO-ops to induce the formation of traumatic HO, which provides novel insights into the molecular basis of HO formation and offers promising targets for future therapeutic strategy. This article is protected by copyright. All rights reserved.

Elbow arthroplasty is safe for the management of simple open distal humeral fractures

BACKGROUND

Elbow arthroplasty (EA) is an established technique for the treatment of select distal humeral fractures, yet little data exists regarding the safety and outcome of EA in the presence of an open distal humeral fracture where the risk of periprosthetic infection is an even greater concern. We hypothesized that EA does not carry an increased risk of infection or other postoperative complications when performed for simple open distal humeral fractures.

METHODS

Seventeen patients underwent total EA (n = 9) or hemiarthroplasty (n = 8) for an open distal humeral fracture. The open fracture component was classified according to the Orthopaedic Trauma Society system as "simple" or "complex." Outcome measures collected included the Mayo Elbow Performance Score (MEPS), range of motion, complications, and reoperations. Patients who underwent primary débridement and implantation were compared with those who underwent preliminary débridement procedures and subsequent staged arthroplasty. A systematic review of the existing literature was performed to analyze other reported cases and contextualize our findings.

RESULTS

The mean follow-up was 46 months (range, 12-138 months). All fractures were multifragmentary and intra-articular. Sixteen patients had a "simple" open fracture and 1 had a "complex" fracture. The overall mean MEPS was 83 (range, 30-100; standard deviation ± 17), with a mean flexion-extension arc of 96°. Patients who underwent primary débridement and implantation demonstrated a higher mean flexion arc (116° vs. 79°, P = .02) than those who underwent staged arthroplasty. The mean MEPS was not significantly different between the groups (90 vs. 78, P = .12). Complications included asymptomatic ulna component loosening (n = 1), joint instability (n = 1), and symptomatic heterotopic ossification (n = 3). There were no deep or superficial infections recorded.

CONCLUSION

EA is safe and effective when performed for simple open distal humeral fractures. Primary débridement and implantation may offer functional benefits over a staged approach.