Clinical outcomes of coronal shear fractures of the distal humerus associated with olecranon fractures

Distal humeral coronal shear fractures are rare and account for around 1% of all fractures at the elbow level and 6% of the distal humeral fractures. Many studies have reported on the associated injuries involving the lateral collateral ligament injuries and radial head fractures in up to 40% and 30% of humeral fractures, but this combination of coronal shear fracture of the trochlea and capitellum associated with olecranon fracture is unusual. Here, we report two cases of distal humerus coronal shear fracture with olecranon fracture treated surgically and establish and discuss the pathomechanisms, diagnosis, and therapeutic issues relating to this fracture.

Coronal shear fractures of the distal humerus involving the capitellum and trochlea are rare injuries. Internal fixation with headless compression screws provides a stable construct facilitating early mobilisation. Our study aimed to identify the key determinants of both radiological and functional outcomes of patients with distal humerus coronal shear fractures treated with internal fixation. A retrospective analysis of 61 patients with distal humerus coronal shear fractures who were treated surgically was done. Demographics, fracture morphology, time to surgery, operative details such as surgical approach and implant used, quality of reduction, time to union, and associated complications from hospital records. Radiological outcomes were assessed using plain radiographs, and the functional outcomes were by Oxford Elbow Score (OES) and Mayo Elbow Performance Index (MEPI). Patients with anatomical reduction of the fracture had better functional outcomes and range of motion. The presence of posterior comminution of capitellum resulted in poorer outcomes (p = 0.03). Delayed presentation did not alter the outcome when the anatomical reduction was achieved. Myositis ossificans was noted in nine patients and non-union in five patients. Two patients developed avascular necrosis of the capitellum and arthritis of the elbow joint. Anatomical reduction and posterior comminution are the two key determinants of the functional outcome in these coronal shear fractures of the distal humerus. Early mobilisation following a stable fixation is crucial in achieving a good outcome.

Because of the complicated anatomy and considerable change in size and morphology with age in teenagers, the appropriate internal fixator of coronal shear fracture of distal humerus is difficult to choose, and therefore, the fixation of this kind of fracture is difficult and controversial. Furthermore, distal humeral fractures in teenagers often involve the epiphysis, the rigid fixation of fracture and the simultaneous minimally invasive and protection of the epiphysis are contradictory. Coronal shear fractures of the distal humerus in teenagers are great challenge for orthopedic surgeons. Three-dimensional (3D) printing designed customized plate in the treatment of coronal fracture of distal humerus in teenager is a potential satisfactory choice in the treatment of the complex fractures. A teenager suffered from an elbow joint injury due to a fall while running, resulting in pain, swelling and limited movement of the elbow joint. The epiphyseal has not closed in this patient, conventional surgical procedures have great traumatic and invasive, and to some extent affect bone growth in children. Coronal shear fracture of right distal humerus according to computed tomography scan. We used 3D printing technology to design an internal fixation device for this patient, which was to treat the distal humeral coronal shear fracture in a teenager via an anterior approach to the elbow joint, and finally the child was instructed to perform immediate postoperative functional exercises and rehabilitation. Radiographic reexamination performed 1 day and 2 month after the operation showed that the internal fixation was in good position, no fracture displacement. the patient was instructed to perform active flexion and extension internal and external rotation of the right elbow 6 weeks postoperatively. The Mayo elbow function score was excellent 5 months postoperatively. The range of motion of the elbow was (15°-130°). The treatment of coronal shear fractures of the distal humerus in teenager is controversial at present. This report 3D printing technology designed customized plate in treatment of such fractures showed satisfactory results, which provides a feasible method for the treatment of fractures without suitable internal fixation devices in the future.

Olecranon fractures are relatively common injuries, accounting for approximately 10% of upper extremity fractures in adults [26]. These fractures may result from a direct blow to the proximal ulna, or indirectly, via the forceful contraction of the triceps against resistance (typically, during a fall onto an outstretched hand). Less commonly, the olecranon may fracture when the elbow is hyperextended, as the bone is impacted against the olecranon fossa of the distal humerus. For unstable injuries, operative fixation typically is required. Even after recovery, loss of ROM is not uncommon. This article provides an overview of olecranon fractures in adults; therefore, discussion of olecranon fractures in skeletally immature patients is beyond the scope of this article.

It is important to estimate the likelihood that a pediatric fracture is caused by osteogenesis imperfecta (OI), especially the least severe type of OI (type 1). We reviewed records of 29,101 pediatric patients with fractures from 2003 through 2015. We included patients with closed fractures not resulting from motor vehicle accidents, gunshot wounds, nonaccidental trauma, or bone lesions. Patients with OI of any type were identified through International Classification of Diseases-9 code. We randomly sampled 500 pediatric patients in whom OI was not diagnosed to obtain a control (non-OI) group. We reviewed age at time of fracture, sex, fracture type, laterality, and bone and bone region fractured. Bisphosphonate use and OI type were documented for OI patients. Subanalysis of patients with type-1 OI was performed. The Fisher exact and χ tests were used to compare fracture rates between groups. P<0.05 was considered significant. Positive likelihood ratios for OI were calculated by fracture pattern. The non-OI group consisted of 500 patients with 652 fractures. The OI group consisted of 52 patients with 209 fractures. Non-OI patients were older at the time of fracture (mean, 9.0±5.0 y) than OI patients (mean, 5.5±4.4 y) (P<0.001). OI patients had more oblique, transverse, diaphyseal, and bilateral long-bone fractures than non-OI patients (all P<0.001). Non-OI patients had more buckle (P=0.013), metaphyseal (P<0.001), and physeal (P<0.001) fractures than OI patients. For patients with type-1 OI and long-bone fractures (n=18), rates of transverse and buckle fractures were similar compared with controls. Transverse humerus (15.2), olecranon (13.8), and diaphyseal humerus (13.0) fractures had the highest positive likelihood ratios for OI, and physeal (0.09) and supracondylar humerus (0.1) fractures had the lowest. Transverse and diaphyseal humerus and olecranon fractures were most likely to indicate OI. Physeal and supracondylar humerus fractures were least likely to indicate OI. Radiographic fracture pattern is useful for estimating likelihood of OI. Level III.

The incidence rate of olecranon fractures is highest in the elderly population. The aim of this study was to determine whether patients with olecranon fractures have similar demographic and risk characteristics compared to patients with osteoporotic upper extremity fractures. A retrospective data analysis was performed with diagnoses for olecranon fracture, distal radius fracture and proximal humerus fracture between 2014 and 2016. A total of 157 olecranon, 1022 distal radius and 451 proximal humerus fractures were identified. The risk of mortality after olecranon and distal radius fractures was comparable but statistically significantly higher after proximal humerus fractures (HR 1.97, 95% CI 1.19-3.27). The risk of subsequent osteoporotic fractures after an olecranon fracture was 10% at 1 year and 14% at 5 years and the risks did not differ statistically after a proximal humerus fracture, 6% and 11% (HR 0.65, 95% CI 0.40-1.06). After a distal radius fracture, the risks were statistically significantly lower: 2% and 5% (HR 0.35, 95% CI 0.22-0.56). Patients with olecranon fractures have essentially similar demographic characteristics compared to patients with distal radius fractures, but the probability for a subsequent fracture is significantly higher and more comparable to patients with proximal humerus fractures.

Surgical treatment of coronal shear fractures of the distal humerus with an intact lateral epicondyle by the lateral combined approach

Chronic capitellum-trochlea coronal shear fractures(defined as untreated injuries > 3 weeks) are complex intraarticular fractures of the distal humerus, primarily caused by missed diagnoses of low-energy traumaand typically requiring open reduction and internal fixation (ORIF).These articular fractures are associated with high complication rates, including nonunion and post-traumatic osteoarthritis. This retrospective analysis of ten patientsevaluated the clinical efficacy of 3D printing-assisted ORIFin improving surgical precision and functional outcomes (assessed by Mayo Elbow Performance Score, MEPS) for chronic coronal shear fractures involving the humeral trochlea and capitellum. This retrospective study included ten patients with chronic coronal shear fractures treated with open reduction and internal fixation between September 2017 and September 2022. 3D-printed anatomical modelswere generated from CT scans using Medraw software to design patient-specific surgical strategies. Postoperative outcomes were assessed using the Mayo Elbow Performance Score (MEPS) by a blinded evaluator. Patients ranged in age from 13 to 67 years (40.8 ± 17.2 years). All patients with closed fractures underwent surgery 5-16 weeks after injury (9.3 ± 3.6 weeks). No early postoperative complications, such as wound healing issues, were observed. Follow-up periods ranged from 8 to 12 months (9.7 ± 1.9 months), and bony union times averaged 12.9 ± 4.1 weeks (range, 8-19 weeks). No long-term complications, including instability or fixation loosening, were reported. The mean MEPS was 92.5 ± 8.2, with excellent results in seven cases and good results in three cases. 3D printing may aid in developing precise, patient-specific surgical plans, potentially improving articular reduction accuracy and minimizing intraoperative challenges in treating chronic coronal shear fractures of the humeral trochlea and capitellum.

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Complex distal humerus coronal shear fractures are rare injuries. These fractures involve small articular fragments and are challenging to fix. Aprospective case series of 10 patients was done at a level 1 trauma centre between February 2017 and July 2021. Dubberley type 3 fractures were included in the study. All patients underwent ORIF using posterior approach with olecranon osteotomy by a single surgeon.Patients were followed up for a minimum of 12months postoperatively. The primary outcome measures were radiographic union and functional status of the limb (DASH score and MEPI score). All patients achieved radiographic union of fracture as well as the osteotomy. The mean DASH score as measured on the final follow-up was 12.6 ± 10.2 and the mean MEPI score was 90 ± 8.2. None of the cases needed reoperation. Consistently good functional outcomes can be obtained in complex coronal shear fractures by posterior approach with olecranon osteotomy. Dubberley type 3b patients should undergo additional plate fixation.

Of 2,502 elbow/humeral injuries treated at our department between 1990 and 2005, we identified a cohort of 20 lateral condylar mass (LCM) fractures of the humerus in children associated with elbow dislocation (n = 12; mean age 8.2 years) or with olecranon fracture (n = 8; mean age 4.1 years). Eight patients with undisplaced fracture pattern were treated conservatively yielding a satisfactory outcome. Good to excellent results were obtained in the majority (85%). Overall, the result was poor in three patients (15%; 25% of the operated cohort) due to terminal 20-30 degrees loss of extension. There was no obvious difference in the outcome between the isolated displaced LCM fractures described in the literature and this cohort. Testing of elbow stability by examination under anaesthesia is stressed. Undisplaced fracture patterns need to be closely observed. Parents should be warned about the likelihood of some degree of unfavourable outcome in the displaced LCM fractures with associated elbow injuries.

Background:Artificial intelligence has been increasingly used for radiographic fracture detection in recent years. However, its performance in the diagnosis of displaced and non-displaced fractures in specific anatomical regions has not been sufficiently investigated. This study aimed to evaluate the accuracy and sensitivity of Chat Generative Pretrained Transformer (ChatGPT-4.0) in the diagnosis of radial head, distal humerus and olecranon fractures.Methods:Anonymized radiographs, previously confirmed by an expert radiologist and orthopedist, were evaluated. Anteroposterior and lateral radiographs of 266 patients were analyzed. Each fracture site was divided into 2 groups: displaced and non-displaced. ChatGPT-4.0 asked 2 questions to indicate whether each image was broken. Responses were categorized as “fracture detected in the first question,” “fracture detected in the second question,” or “no fracture detected.”Results:ChatGPT-4.0 showed a significantly higher accuracy in diagnosing displaced fractures at all sites (P < .001). The highest fracture detection rate in the first question was observed for displaced distal humeral fractures (87.7%). The success rate was significantly lower in non-displaced fractures, and in the non-displaced group the highest diagnostic rate was observed in radial head fractures (25.3%). No statistically significant difference was found in pairwise sensitivity comparisons between non-displaced fractures (P > .05).Conclusion:ChatGPT-4.0 shows promising diagnostic performance in the detection of displaced olecranon, radial head and distal humeral fractures. However, its limited success in non-displaced fractures indicates that the model requires further training and development before clinical use.Level of evidence:Level 3.

Objective To investigate the surgical treatment and outcome of distal humeral shear fractures in adults through Kaplan approach.Methods Nine patients with closed shear fracture of the distal humerus were surgically treated through Kaplan approach from September 2005 to September 2009.The lateral collateral ligament was released only in 1 case.All the fractures were classified into type 1A (3 cases),type 1B (1 case),type 2A (1 case),type 3A (1 case) and type 3B (3 cases) according to Dubberley classification.Under the direct vision,cannulated screw was used after anatomic reduction was confirmed by fluoroscopy.Results All fractures were reduced anatomically without any neural or vascular injury.Only 1 case of grade 1 heterotopic ossification was found 12-24 months postoperatively.There were excellent in 4 cases,and good in 5 cases.The average Broberg-Morrey score was 94.2.The average arc of flexion-extension was 116°.As to the 4 cases with posterior comminution,the averaged score and the arc of flexion-extension was 92.8 and 104°,respectively.Conclusion Through Kaplan approach,the reduction and internal fixation of distal humeral shear fractures can be manipulated successfully with lateral collateral ligament intact,and the short-term outcome is satisfactory.Dubberley classification which focused on the severity and prognosis is helpful to make a surgical plan. Key words: Humeral fractures; Internal fixators; Surgical procedures,operative

Effects of trochlear fragmentation on functional outcome in coronal shear fractures: a retrospective comparative study.

Pediatric olecranon fractures are relatively rare, accounting for only 5% of all childhood elbow fractures. The majority of patients are between 5 and 10 years of age with approximately 65% being young males. The most common mechanism of injury involves a fall onto either an outstretched hand or a flexed elbow. In a small group of patients, such as those with osteogenesis imperfecta, pathologic olecranon fractures may occur. With the exception of injuries in young children with incomplete ossification of the olecranon apophysis, most olecranon fractures are diagnosed on radiographs. It is important to rule out concomitant injuries when viewing initial radiographs, as anywhere from 14 to 77% of olecranon fractures are associated with an additional fracture in the distal humerus or radius, either proximally or in the diaphysis. Non-displaced olecranon fractures heal with cast immobilization. Fractures with displacement greater than 2 mm generally require operative intervention, the manner of which is dictated by the location of the fracture and the fracture pattern. Outcomes are favorable in most patients treated both surgically and nonsurgically. This chapter will describe the evaluation, treatment, and outcomes of children and adolescents with olecranon fractures. Fractures of the proximal ulna are associated with radiocapitellar joint dislocation or subluxation (Monteggia lesions) and are discussed elsewhere in this text.