Analysis of magnetic resonance imaging-confirmed soft tissue injury pattern in simple elbow dislocations

Creation of a replicable anatomic model of terrible triad of the elbow

BACKGROUND

Terrible triad of the elbow (TTE) is a complex dislocation associating radial head (RH) and coronoid process (CP) fractures. There is at present no reproducible anatomic model for TTE, and pathophysiology is unclear. The main aim of the present study was to create and validate an anatomic model of TTE. Secondary objectives were to assess breaking forces and relative forearm rotation with respect to the humerus before dislocation.

METHODS

An experimental comparative study was conducted on 5 fresh human specimens aged 87.4 ± 8.6 years, testing 10 upper limbs. After dissection conserving the medial and lateral ligaments, interosseous membrane and joint capsule, elbows were reproducibly positioned in maximal pronation and 15° flexion, for axial compression on a rapid (100 mm/min) or slow (10 mm/min) protocol, applied by randomization between the two elbows of a given cadaver, measuring breaking forces and relative forearm rotation with respect to the humerus before dislocation.

RESULTS

The rapid protocol reproduced 4 posterolateral and 1 divergent anteroposterior TTE, and the slow protocol 5 posterolateral TTE. Mean breaking forces were 3,126 ± 1,066 N for the lateral collateral ligament (LCL), 3,026 ± 1,308 N for the RH and 2,613 ± 1,120 N for the CP. Comparing mean breaking forces for all injured structures in a given elbow on the rapid protocol found a p-value of 0.033. Comparison of difference in breaking forces in the three structures (LCL, RH and CP) between the slow and rapid protocols found a mean difference of -4%. Mean relative forearm rotation with respect to the humerus before dislocation was 1.6 ± 1.2° in external rotation.

CONCLUSIONS

We create and validate an anatomic model of TTE by exerting axial compression on an elbow in 15° flexion and maximal pronation at speeds of 100 and 10 mm/min.

Look for the POLESTAR (POsteroLateral Engagement of Soft Tissue And Radial head) while navigating around elbow dislocation

BACKGROUND

Elbow dislocation is frequently associated with bony and osteochondral posterolateral capitellar lesions that are often under-reported. We aim to examine the radiologic signs of posterolateral lesions on computed tomography (CT).

METHODS

A retrospective analysis of CT scans was performed. Patients were classified into 4 groups: (1) simple elbow dislocation, (2) elbow dislocation with a fracture of the coronoid tip, (3) elbow dislocation with coronoid tip fracture and a radial head fracture inferior or equal to the anterior third, and (4) terrible triad defined as elbow dislocation with concomitant coronoid and radial head fracture with a more important involvement. Patients with a more complex fracture pattern were excluded. The presence of POsteroLateral Engagement of Soft Tissue And Radial head (POLESTAR) patterns was analyzed and subclassified as impaction type or fragmentation type.

RESULTS

Fifty-one CT scans met the inclusion criteria. POLESTAR lesions were identified in 48 cases (94%): 46% impaction-type and 54% fragmentation-type POLESTAR. Analyzing patients from grade 1 to 4, impaction-type POLESTAR was found, respectively, from 40% to 57%, whereas fragmentation type was present from 60% to 43%.

CONCLUSIONS

This study shows a high incidence of POLESTAR lesions (94%) that can be present as impaction type or fragmentation type. Based on our preliminary results, impaction type is more common in grades 3 and 4, whereas fragmentation type is more frequent in grades 1 and 2.

Ultrasonographic examination of acute soft tissue lesions in the elbow has good inter-rater reliability and acceptable agreement with magnetic resonance imaging

BACKGROUND

Ultrasonography (US) has been suggested as a valuable complement to clinical and radiologic examinations in elbow trauma. Magnetic resonance imaging (MRI) has been the method of choice, despite fair to moderate inter-rater reliability (IRR). US has potential advantages but is assessor dependent and the IRR scarcely examined. The primary aim of the present study was to investigate IRR for US and secondarily interobserver agreement (IOA) between US and MRI in the acute phase after elbow trauma. Acute phase was defined as 2 weeks and, if applicable, the following weekend. The hypothesis was that US reliability would be at least substantial for complete muscle or ligament lesions.

METHODS

A total of 116 patients (50 men, median age 47 [range 19-87] years) who had an elbow trauma with dislocation and/or fracture were included. Exclusion criteria were prior injury to the same elbow, and US and/or MRI not possible within 16 days. During US, the condition of muscle origins at the epicondyles and collateral and annular ligament complexes was recorded in a predesigned protocol, with the alternatives intact, partially or completely torn. Seventy-two patients had a second US examination the same day by an independent upper extremity surgeon, and 58 of the 116 patients underwent an MRI before or after the US, evaluated by 2 radiologists using the same protocol. IOA and IRR between assessors and modalities were analyzed with kappa statistics and interpreted according to Landis and Koch. Perfect agreement (PA) was reported in percentages.

RESULTS

US examination within 2 weeks was feasible with tolerable discomfort. Defining muscle origins and ligaments as intact or completely torn, the US IRR ranged from substantial to near perfect (kappa 0.63-1, PA 93%-100%). Intact tissues vs. tear (partial and complete tear combined) or intact vs. partial vs. complete tear resulted in kappa values from moderate to substantial and PA 74%-96% with lowest reliability for the muscle origins. The IOA between MRI and US ranged from fair to near perfect for no tear vs. complete tear (kappa 0.25-1, PA 65%-100%). Agreement between no tear and tear (partial and complete together) ranged from fair to substantial (0.25-0.66, PA 63%-89%) and no tear vs. partial or complete tear ranged from fair to moderate (0.25-0.53, PA 50%-79%).

CONCLUSION

US in the acute setting is suitable and reliable for diagnosis of ligament injuries in the elbow and is in addition fast, cheap, and easily accessible. The agreement with MRI seems to vary with the structure assessed and severity of the lesions, ranging from fair to near perfect.

Coronoid fractures and complex elbow instability: current concepts

Fractures of the coronoid process typically occur as part of more complex injury patterns, such as terrible triads, trans-olecranon fracture-dislocations, posteromedial rotatory injuries or Monteggia-like lesions. Each pattern is associated with a specific type of coronoid fracture with regard to shape and size and specific soft-tissue lesions. O' Driscoll classification incorporates those associations identifying three major types of fractures: tip, anteromedial facet, and basal fractures. The objective of this study is to review the most common types of complex elbow instability, identify the indications for coronoid fixation and guide the appropriate management. Tip fractures as those seen in terrible triads can conditionally left untreated provided that elbow stability has been restored after radial head fixation and ligaments repair. Anteromedial facet fractures benefit from a buttress plate, while large basilar fractures can be effectively secured with posteroanterior screws. Coronoid reconstruction with a graft should be considered in post-traumatic cases of chronic coronoid deficiency.

Clinical value of quantitative parameters of MSCT in the diagnosis of occult femoral neck fractures

To explore the clinical value of quantitative parameters of multi-slice computer tomography (MSCT) in the diagnosis of occult femoral neck fractures.The clinical data of 94 patients with suspected occult femoral neck fractures admitted to our hospital from April 2021 to April 2022 were selected for retrospective analysis, and they were divided into group A (accurate diagnosis, n = 63) and group B (non-occult femoral neck fractures, n = 31) according to the results of pathological and surgical diagnosis as the gold standard. All patients received MSCT examination to obtain quantitative parameters related to imaging, and receiver operator characteristic (ROC) curves were used to comprehensively evaluate the clinical value of quantitative parameters of MSCT in the diagnosis of occult femoral neck fractures.The quantitative parameters of MSCT in group A were overtly lower than those in group B (P < 0.05). The AUC value, Youden index and sensitivity of the combined detection were higher than those of single detection.The use of quantitative parameters of MSCT effectively reduces the missed diagnosis rate of occult femoral neck fractures, which could make an accurate diagnosis of the fracture type, as a basis for the formulation of clinical treatment plans.

Simple acute postero-lateral elbow dislocation: A historical perspective

PURPOSE

The aims of this study were to summarize (1) the historical knowledge of the posterolateral elbow dislocation (PLED) pattern and the biomechanical, radiographic, and clinical data that engendered its evolution; and (2) to help clinicians better understand the management of PLED.

METHODS

A literature search was performed using Ovid, Scopus and Cochrane Library, and the Medical Subject Headings vocabulary. Results are discussed as a chronologic review of the relevant literature between 1920-2022.

RESULTS

In 1966 Osborn and Cotterill were the first to describe posterolateral rotatory instability (PLRI) causing the PLED. Several theories on PLED were then published by others surgeons as our understanding of elbow biomechanics continued to improve. Multiple treatment protocols have been designed based on the aforementioned theories. Conservative and surgical treatment for PLED provides excellent functional outcomes. However, high rates of persistent pain stiffness and instability have been reported long-term, and no single approach to treatment has been widely accepted.

CONCLUSION

Despite a growing body of biomechanical evidence, there is no consensus surgical indication for the treatment of PLED. Both conservative and surgical management result in satisfactory functional outcomes after PLED. However, elevated rates of residual pain, and instability have also been described and may limit heavy labor and sports participation. The next challenge for elbow surgeons will be to identify those patients who would benefit from surgical stabilization following PLED.

Sensitivity and specificity of the posterolateral rotatory drawer test in the diagnosis of lateral collateral ligament insufficiency of the elbow

BACKGROUND

Numerous clinical tests are described for the diagnosis of chronic lateral collateral ligament (LCL) insufficiency of the elbow; however, none of these tests have been adequately assessed for sensitivity, with at most 8 patients included in previous studies. Furthermore, no test has had specificity assessed. The posterolateral rotatory drawer (PLRD) test is thought to have improved diagnostic accuracy over other tests in the awake patient. The aim of this study is to formally assess this test using reference standards in a large cohort of patients.

METHODS

A total of 106 eligible patients were identified for inclusion from a single-surgeon database of operative procedures. Examination under anesthetic (EUA) and arthroscopy were chosen as the reference standards to compare the PLRD test against. Only patients with a clearly documented PLRD test finding performed preoperatively in the clinic, and a clearly documented EUA and/or arthroscopic findings from surgery were included. A total of 102 patients underwent EUA, 74 of whom also underwent arthroscopy. Twenty-eight patients had EUA, and then an open procedure without arthroscopy. Four patients had arthroscopy without a clearly documented EUA. Sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) were calculated with 95% confidence intervals.

RESULTS

Thirty-seven patients had a positive PLRD test, and 69 had a negative test. Compared to the reference standard of EUA (n = 102), the PLRD test had a sensitivity of 97.3% (85.8%-99.9%) and a specificity of 98.5% (91.7%-100%) (PPV = 0.973, NPV = 0.985). Compared to the reference standard of arthroscopy (n = 78), the PLRD test had a sensitivity of 87.5% (61.7%-98.5%) and a specificity of 98.4% (91.3%-100%) (PPV = 0.933, NPV = 0.968). Compared to either reference standard (n = 106), the PLRD test has a sensitivity of 94.7% (82.3%-99.4%) and a specificity of 98.5% (92.1%-100%) (PPV = 0.973, NPV = 0.971).

CONCLUSION

The PLRD test demonstrated an overall sensitivity of 94.7% and specificity of 98.5% with high positive and negative predictive values. This test is recommended as the primary diagnostic tool for LCL insufficiency in the awake patient and should be widely incorporated into surgical training.

Terrible triad injury of the elbow: a spectrum of theories

For more than one century, understanding the injury mechanism leading to the terrible triad of the elbow (TTE) was a significant challenge for surgeons. We aimed to summarize: (1) the history of the treatment of TTE and (2) the increasing scientific knowledge that supported its evolution. Five electronic databases were searched between 1920 and 2022. Results were reported as a comprehensive review of the relevant literature. Between 1940 and 1980, surgical exploration allowed observation of complex elbow instability involving both radial head, coronoid process, and ligament(s) injuries. In 1966, Osborne introduced the concept of posterolateral rotatory instability as the first mechanism injury to explain the complex elbow instability. From 1980 to 1995, a biomechanical revolution by American pioneers critically improved our understanding of elbow instability. After 1992, a few unifying theories and surgical protocols were provided, but those have divided the surgeons' population. The formalization of the TTE treatment allowed avoiding of terrible short-term outcomes. However, post-traumatic osteoarthritis (PTOA) at long-term follow-up is still an issue. No consensual surgical protocol for the treatment of TTE has been widely accepted. While the outcomes of the TTE have been improved, the rate of PTOA at long-term follow-up is still high regardless of the treatments. The terrible triad has given way to the subtle triad with persistent microinstability of the elbow. The next challenge for elbow surgeons is to diagnose and fix this persistent subclinical instability after surgery in order to prevent the onset of PTOA.

Acute elbow dislocation: a critical appraisal of the literature

Background

The purpose of this study was to perform a narrative review of acute elbow dislocation (AED). There are certain aspects of the management of AED that are controversial, including type and length of immobilization, indications for surgery, type of surgery, and new evidence available.

Material and methods

A literature search was performed using MEDLINE and Embase databases for studies regarding AED. Preference was given to studies according to their level of evidence. Studies regarding the outcome of conservative and surgical treatment, including patient-reported outcomes, complications, and conversion to stabilization or revision surgery were included.

Results

We found only 1 level I study and 3 level II randomized clinical trials. The rest consisted of level III-V evidence. Conservative care continues to be the standard of care for stable AEDs. Shorter immobilization periods are favored when possible. A consensus definition of an unstable elbow still needs to be improved. Unstable simple elbow dislocation may benefit from surgical intervention with different techniques showing similar outcomes. Advances in surgical procedures and suture designs, including tapes, and ligament augmentation, need to prove their role in managing acute elbow instability.

Conclusion

There is a need for higher quality studies after the reduction of an AED, including discerning the outcome of specific patterns of injury and particular groups of patients like high-level athletes or people with preoperative laxity. Comparison between different surgical techniques is warranted, including arthroscopic techniques and types of ligament augmentation to promote early motion and reduce postoperative stiffness.

[Augmented primary sutures "internal bracing" following ligamentous elbow dislocation]

OBJECTIVE

Aim of surgical treatment is the primary stabilization of the unstable elbow following a ligamentous elbow dislocation.

INDICATIONS

Ligamentous elbow dislocations are typically accompanied by injuries to the surrounding musculature and collateral ligaments of the elbow joint. Surgical treatment is indicated in case of failure of nonoperative therapy, i.e., when a dislocation can only be prevented in immobilization > 90° and pronation of the elbow or an active muscular centering of the elbow fails after 5-7 days.

CONTRAINDICATIONS

Contraindications for a solely "internal bracing" augmented primary suture are generally in the case of accompanying bony injuries in elbow dislocations, extensive soft-tissue injuries, and septic arthritis of the elbow.

SURGICAL TECHNIQUE

The augmented primary suture of the elbow is performed using both a lateral (Kocher or Kaplan) and medial (FCU split) approach to the elbow. After reduction of the elbow, the collateral ligaments are first augmented with high-strength polyethylene suture and fixed in the distal humerus together with another high-strength polyethylene augmentation suture. The extensors and flexors are then fixed to the medial and lateral epicondyle, respectively, using suture anchors.

POSTOPERATIVE MANAGEMENT

The aim of the postoperative management is early functional exercise of the elbow. The elbow is placed in an elbow brace to avoid varus and valgus load.

RESULTS

Between August 2018 and January 2020, a total of 12 patients were treated with an augmented primary suture following unstable ligamentous elbow dislocation. After a mean follow-up of 14 ± 12.7 months, the mean Mayo Elbow Performance Score was 98.5 points with a mean functional arc of 115°. None of the patients reported a recurrent dislocation or persistent instability of the elbow.

Terrible triad injury of the elbow: a historical perspective

PURPOSE

The aims of this study are to summarize (1) the history of terrible triad injury (TTi) treatment and (2) the clinical and biomechanical data that engendered its evolution.

METHODS

A literature search was performed using five electronic databases. Results were discussed as a chronologic review of the relevant literature between 1920 and 2022.

RESULTS

In 1962, Osborne was the first to describe a link between elbow dislocation, radial head fracture, and lateral collateral ligament complex injury via a novel mechanism: posterolateral rotatory instability (PLRI). Given that untreated elbow instability leads to post-traumatic osteoarthritis (PTOA), there has been increasing interest in elbow biomechanics since the 1980s. Data from studies in that period revolutionized the approach to elbow instability. The authors demonstrated that TTi could occur via a PLRI mechanism with a disruption of the lateral collateral ulnar ligament and a functionally competent anterior medial collateral ligament (aMCL). Since the 1990s, due to the difficulty in identifying its pathoanatomic features, some began to speculate about a sequence of injuries and mechanisms leading to TTi. However, the clinical literature has largely been unable to reproduce in vitro findings describing the pathomechanics of TTi. Some aspects of treatment remain controversial including systematic coronoid and aMCL repair.

CONCLUSION

Despite a growing body of biomechanics data, there is no widely accepted surgical protocol for the treatment of TTi. Functional outcomes among patients have greatly improved. Better diagnosis and treatment of infra-clinical instability after a TTi may be an important stepping stone to prevent the onset of moderate/severe PTOA.

A Novel Suture-Preset Spring Plate System (SSPS) for Comminuted Coronoid Process Fracture in the Elbow

OBJECTIVE

This study is aimed to investigate the clinical outcomes of a novel SSPS for fixation of the comminuted coronoid fracture.

METHODS

A retrospective study was carried out in the patients with comminuted fractures of the coronoid treated by SPSS fixation between January 2014 and December 2018. A total of 17 patients (17 sides) was included in our study, including 11 male and six female, with a mean age range from 18 to 60. All cases started to functional rehabilitation immediately after the operation. Clinical outcomes were evaluated both radiographically and functionally at the follow-up visit, including the elbow instability, range of motion and Mayo elbow performance score (MEPS).

RESULTS

According to the O'Driscoll classification system, there was two side of type 1.2, two of type 2.1, four of type 2.2, three of type 2.3, two of 3.1 and four of type 3.2. The surgery was carried out by Kocher and anteromedial approach in 12 patients, posterior and anteromedial approach in four, anterior approach in one. The average operation time and intraoperative blood loss was 129.41±43.87 min and 115.29±104.65 ml. The median follow-up time was 9 months (range, 6 to 15 months). The mean flexion, extension, pronation and supination motion was 138.76±8.67 degrees, 20.00±13.58, 82.94±5.32and 74.12±14.39 respectively at final follow up. The mean MEPS score was 89.76±8.46, including 11 excellent, 3 good and 3 fair result. The mean VAS score was 1.94±0.97. The mean union time of coronoid fractures was 2.77±0.31 months according to the established standard of healing. There were no significant differences in clinical outcomes among groups according to the O'Driscoll classification (P > .05) and ligament repair strategy (P > .05). No patient underwent instability or dislocation of the elbow during follow up. There were two cases with mild ulnar nerve symptoms which recovered totally at follow up. Meanwhile, there were three cases with heterotopic ossification of the elbow.

CONCLUSION

Our findings demonstrated that the SSPS can provide a reliable fixation for the comminuted coronoid fracture with satisfactory clinical outcomes.

Ultrasonography: an interesting imaging method for ligament assessment during the acute phase of closed elbow injuries

PURPOSE

To evaluate whether ultrasonography can be used to explore the medial and lateral ligament structures during the acute phase of a closed elbow injury.

METHODS

A single-center, prospective study performed between December 2019 and June 2020, including patients who suffered a radial head fracture or elbow dislocation. Two radiologists did a blinded analysis using ultrasonography of visibility, injury grade, and presence of bone avulsion for the radial collateral ligament (RCL), lateral ulnar collateral ligament (LUCL), annular ligament (AL), and anterior (MCLant) and posterior bundles (MCLpost) of the medial collateral ligament. The inter-rater agreement was calculated. The ultrasonography findings were compared with the intraoperative findings in the patients who subsequently underwent surgery.

RESULTS

Forty patients were included (28 radial head fractures and 12 elbow dislocations). The inter-rater agreement was strong for all the study parameters (kappa between 0.65 and 1), except for the visibility of the LUCL (kappa 0.52) and the visibility and appearance of the MCLpost (kappa 0.54 and 0.47, respectively). The injured ligaments were thicker than their contralateral counterparts (p < 0.05). In the 10 patients who underwent surgery, the radiological-surgical correlation was 100% for the RCL and medial ligaments and 70% for the LUCL.

CONCLUSION

Ultrasonography is a reproducible examination that can be used to assess the damage to elbow ligaments during the acute phase following an injury. This examination could be incorporated into the exploration protocol for elbow injuries during the preoperative assessment and to adapt the treatment.

Magnetic Resonance Imaging Findings After Elbow Dislocation: A Descriptive Study

BACKGROUND

The elbow is one of the most commonly dislocated joints, and dislocation is usually accompanied with an assortment of soft tissue injuries. The purpose of this study was to retrospectively analyze and describe the patterns of ligamentous, tendinous, and muscular injuries in patients with an acute elbow dislocation and subsequent magnetic resonance image (MRI) evaluation.

METHODS

From 2008 to 2020, 235 patients clinically diagnosed with an elbow dislocation were seen in the department, of which only 19 underwent an MRI of the affected elbow. Twelve patients met inclusion criteria, and MRIs were evaluated by both a radiologist and an upper extremity orthopedic surgeon. Magnetic resonance images were assessed for injury to the ulnar collateral ligament (UCL); radial collateral ligament (RCL); lateral ulnar collateral ligament (LUCL); common flexor and extensor tendons; biceps, brachialis, and triceps tendons; fracture; and joint effusion.

RESULTS

Magnetic resonance imaging findings included the following: UCL was injured in 11 of 12 patients; RCL was injured in 9 of 12 patients; LUCL was injured in 9 of 12 patients; common flexor tendon was injured in 11 of 12 patients; and common extensor tendon was injured in 9 of 12 elbows. The biceps, brachialis, and triceps tendons showed injury in 1 of 12, 2 of 12, and 2 of 12 elbows, respectively. Four elbows had at least 1 fracture present, whereas 8 demonstrated an effusion.

CONCLUSIONS

In this series, injuries to the UCL and common flexor tendon were most common. Although ligamentous injuries are exceedingly common in elbow dislocations, large studies of MRI findings prove difficult due to MRI costs.

The radiological findings in complex elbow fracture-dislocation injuries

Elbow fracture-dislocation is a complex injury which can lead to significant bony and soft tissue damage. Surgical intervention is guided towards restoring joint stability, allowing early mobilization and preventing long-term joint stiffness. The most common types are posterolateral, posteromedial, Monteggia type (and variants), and anterior trans-olecranon fracture-dislocations. Posterolateral fracture-dislocation is characterized by a radial head fracture (± anterolateral coronoid fracture) and typically capsuloligamentous disruption (lateral collateral ligaments injury is the most common). A posterolateral fracture-dislocation with radial head and coronoid anterolateral facet fractures is termed a terrible triad injury. In posteromedial fracture-dislocation, there is a fracture of the anteromedial facet of the coronoid, typically with proximal avulsion of the lateral collateral ligaments (± injury to the posterior bundle of the ulnar collateral ligament). Monteggia fracture-dislocation injuries demonstrate proximal ulnar fracture (with possible involvement of the olecranon and the coronoid) and radial head dislocation. These can be divided into apex anterior or apex posterior variants. The latter are commonly associated with radial head fractures and lateral ligamentous injury, and have a worse prognosis. In trans-olecranon fracture-dislocation, there is significant disruption of the greater sigmoid notch and the olecranon, with various involvement of the coronoid and the proximal ulna. The article describes the radiological findings and outlines the management principles in complex elbow fracture-dislocation injuries.

Dislocations of the elbow - An instructional review

Dislocations of the elbow require recognition of the injury pattern followed by adequate treatment to allow early mobilisation. Not every injury requires surgery but if surgery is undertaken all structures providing stability should be addressed, including fractures, medial and lateral ligament insertion and the radial head. The current concepts of biomechanical modelling are addressed and surgical implications discussed.

The three-column concept of elbow joint stability and the Wrightington elbow fracture-dislocation classification, emphasizing the role of cross-sectional imaging

Elbow fracture-dislocation is a complex injury with a combination of osseous and soft tissue disruption. Different classification systems have been used to describe the injury pattern and help guide the management. The article describes the important cross-sectional findings in complex elbow fracture-dislocation injuries based on the relatively new Wrightington classification. This includes the various elements and patterns seen in elbow fracture-dislocations providing a simple and comprehensive system to classify these injuries and help guide the surgical management. The article also describes the three-column concept of elbow joint stability, dividing the elbow joint osseous structures into lateral, middle and medial columns. Detailed radiological assessment of the fractures pattern is vital to understand the mechanism of injury, allowing clinicians to predict the associated capsuloligamentous injury and help guide the management decisions. The Wrightington elbow fracture-dislocation classification categorizes the injuries according to the ulnar coronoid process and radial head fractures. Type A is an anteromedial coronoid fracture. Type B is a bifacet or basal coronoid fracture, with B + indicating associated radial head fracture. Type C is a combined anterolateral facet and radial head or comminuted radial head fractures. Type D is a diaphyseal ulnar fracture, with D + indicating associated radial head fracture.

Increased volume and collagen crosslinks drive soft tissue contribution to post-traumatic elbow contracture in an animal model

Post-traumatic joint contracture (PTJC) in the elbow is a biological problem with functional consequences. Restoring elbow motion after injury is a complex challenge because contracture is a multi-tissue pathology. We previously developed an animal model of elbow PTJC using Long-Evans rats and showed that the capsule and ligaments/cartilage were the primary soft tissues that caused persistent joint motion loss. The objective of this study was to evaluate tissue-specific changes within the anterior capsule and lateral collateral ligament (LCL) that led to their contribution to elbow contracture. In our rat model of elbow PTJC, a unilateral surgery replicated damage that commonly occurs due to elbow dislocation. Following surgery, the injured limb was immobilized for 42 days. The capsule and LCL were evaluated after 42 days of immobilization or 42 days of immobilization followed by 42 days of free mobilization. We evaluated extracellular matrix protein biochemistry, non-enzymatic collagen crosslink content, tissue volume with contrast-enhanced micro-computed tomography, and tissue mechanical properties. Increased collagen content, but not collagen density, was observed in both injured limb capsules and LCLs, which was consistent with the increased tissue volume. Injured limb LCLs exhibited decreased normalized maximum force, and both tissues had increased immature collagen cross-links compared to control. Overall, increased tissue volume and immature collagen crosslinks in the capsule and LCL drive their contribution to elbow contracture in our rat model.

EFFICACY AND MECHANISM OF TRADITIONAL CHINESE MEDICINE GEL IN SPORTS-RELATED SOFT TISSUE INJURY

ABSTRACT Soft tissue injury is the most common disease in orthopedics, and it is also the most easily neglected disease in sports. Without timely and effective treatment, it is easy to develop into malignant strain and seriously affect life and sports. In view of this, the aim of this study is to analyze the effect and mechanism of traditional Chinese medicine gel in treating such injuries in the light of the characteristics of sports-related soft tissue injury. The right gastrocnemius muscle injury was simulated in 36 adult male rats. Chinese medicine gel and tincture were used to treat it. The contents of interleukin, alanine aminotransferase, blood urea nitrogen and prostaglandin E2 in the blood of rats under different courses of treatment were analyzed to explore recovery in four rats. The results showed that the levels of interleukin and prostaglandin E2 in the blood of rats treated with drugs were significantly lower than those in the control group (p<0.05), indicating that both drugs have obvious therapeutic effects on soft tissue injury. The content of interleukin in the blood of the Chinese medicine gel group was slightly lower than that of the tincture group, indicating that the Chinese medicine gel could affect the recovery of soft tissue injury by affecting leukocyte interleukin. This result is helpful in the treatment of soft tissue injury in sports and to further improve the therapeutic effect of traditional Chinese medicine gel.

Effect of the medial collateral ligament and the lateral ulnar collateral ligament injury on elbow stability: a finite element analysis

Ligaments are the most important stabilizer of elbow. However, the stress of ligaments is hard to measure because of the complex biomechanical environment in the elbow. Our objective was to develop a human elbow finite element model and to validate it by a comparison with previous experimental data. Then several different ligaments injury conditions and elbow flexion were simulated to analyse the elbow instability and to stress the biomechanical consequences. The computational investigation of different effects of ligament constraints of elbow was studied by means of finite element analysis. The stress of the anterior bundle was almost greater than other ligaments in all conditions, which played the most important role during the elbow flexion. The posterior bundle was the secondary stabilizer during flexion after the anterior bundle. The lateral ulnar collateral ligament (LUCL) injury could result in an increase of the ulnar cartilage stress. The anterior bundle and the LUCL were recommended to be repaired in elbow joint dislocations and fractures. This study could help understand the dynamic effects of ligaments on the joint over the entire extension by investigating the tissue stress.

Injury patterns following simple elbow dislocation: radiological analysis implies existence of a pure valgus dislocation mechanism

INTRODUCTION

The aim of the present study was to analyze the injury pattern and thus the dislocation mechanism after simple elbow dislocation using radiographs and magnetic resonance imaging (MRI) data sets.

MATERIALS AND METHODS

The MRI data sets of 64 patients with a mean age of 44 years (18-77 years) were analyzed retrospectively. The inclusion criteria for the study were (1) radiograph with confirmed simple elbow dislocation, (2) low-energy trauma, (3) MRI of the affected elbow ≤ 3 weeks after trauma. The dislocation direction was determined using radiographs. The integrity of the lateral collateral ligament complex (LCLC), common extensor origin (CEO), anterior capsule (AC), medial collateral ligament (MCL), and common flexor origin (CFO) as well as the joint congruity were assessed based on MRI.

RESULTS

34 patients (53%) had a posterolateral, 26 patients (41%) a posterior, and 4 patients (6%) a posteromedial dislocation. LCLC and AC were affected in 64 out of 64 patients (100%). MCL was affected in 58 patients (91%). CEO were affected in 25 patients (39%) and the CFO in 20 patients (31%). In 11 patients (17%) the injury pattern was more pronounced medially than laterally (MCL, CFO, LCLC), with 2 of these patients exhibiting only a partial LCLC tear. All cases with joint incongruency (n = 12, 19%) showed CEO and/or CFO involvement.

CONCLUSIONS

Simple elbow dislocation leads to a very heterogeneous spectrum of soft tissue injury pattern. A small proportion of patients showed medially pronounced injury patterns. These findings strongly indicate existence of a "reversed Horii circle" with an underlying valgus mechanism (medial force induction) originating and continuing from medial to anterior.

Acute elbow dislocation: comparison between magnetic resonance imaging and intra-operative finding of ligament injury

PURPOSE

The aim of this current study was to assess elbow ligament tears after dislocation using magnetic resonance imaging (MRI) and to correlate any pre-operative imaging with intra-operative findings of elbow ligament tears.

METHODS

We prospectively included 32 patients with acute elbow dislocation investigated by MRI at a means of five days from dislocation. A simple elbow dislocation was diagnosed in 14 patients (44%); associated bone injuries were identified in 18 elbows (56%). Surgical repair of elbow ligaments was carried out in 23 patients, and nine cases were treated non-operatively. A blinded MRI evaluation of all 32 elbows was performed by an orthopaedic surgeon (rater 1) and a musculoskeletal radiologist (rater 2).

RESULTS

Inter-rater agreement for MRI evaluation of 32 was poor for lateral ulnar collateral ligament (LUCL) tears, fair for radial collateral ligament (RCL), moderate for annular ligament (AL), and fair for ulnar collateral ligament (UCL). All tears were reported as complete by rater 1; 13/32 partial tears were identified by rater 2 (LUCL = 2, RCL = 2, UCL = 9). Correlation between surgical and MRI findings showed good inter-rater agreement for LUCL and AL tears in both raters. Agreement for RCL tear was poor for rater 1 and fair for rater 2; agreement for UCL tear was fair for rater 1 and poor for rater 2. Intra-operative findings showed ten radial head fractures (RHFs) and ten coronoid fractures (CFs). LUCL tears were found in the four cases of type II RHFs and in 3/4 cases of CFs. Bone injuries and ligament tears were not significantly associated.

CONCLUSION

MRI scan supported surgeons to identify soft tissue injuries and to address the most suitable surgical approach after acute elbow dislocation. Inter-observer agreement for intra-operative findings was high for LCL complex injuries and poor for UCL.

Common Extensor Complex Is a Predictor to Determine the Stability in Simple Posterolateral Elbow Dislocation: Analysis of MR Images of Stable vs. Unstable Dislocation

Simple posterolateral elbow dislocations (SPLED) may be treated nonoperatively using closed reduction, followed by controlled mobilization. However, the extent of soft tissue injuries might affect the choice of treatment, rehabilitation approach, and prognosis. The purpose of this study is to compare the characteristics of soft tissue injuries between patients with unstable and stable SPLED using MRI findings. Thirty MRIs of elbows with SPLED (unstable group (n = 15); stable group (n = 15)) were randomly reviewed by two experienced musculoskeletal radiologists. Soft tissue injuries were characterized as an intact, partial tear or complete tear for the: medial collateral ligament (MCL) complex, common flexor complex, lateral collateral ligament (LCL) complex, common extensor complex, anterior capsule, and posterior capsule. Moderate to substantial interobserver reliability and substantial to perfect intraobserver reliability were observed for medial and lateral complexes in SPLED. The proportion of soft-tissue injuries of the common extensor complex were significantly different between the unstable (four partial tears and 11 complete tears) and stable groups (11 partial tears and four complete tears). In conclusion, based on MRI findings, the degree of common extensor complex injuries may be a predictor of stability and help inform treatment decisions for SPLED.

Distribution of Osteochondral Lesions in Patients With Simple Elbow Dislocations Based on MRI Analysis

Background:

The clinical relationship between osteochondral lesions and long-term outcomes and patterns in the elbow joint has not yet been established. A sole evaluation from plain standard radiography may underestimate the severity of bony lesions in patients with simple dislocations. It has been suggested that the mechanism of a posterior elbow dislocation could be inferred from the pattern of bony contusions and osteochondral lesions visible on magnetic resonance imaging (MRI) in patients with simple elbow dislocations.

Purpose/Hypothesis:

The purpose of this study was to describe the incidence and distribution of osteochondral lesions based on MRI findings in patients with simple elbow dislocations. We hypothesized that (1) osteochondral lesions are consistently found in patients with simple elbow dislocations and (2) the distribution and severity of osteochondral lesions may explain the mechanism of the simple elbow dislocation.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective review of 43 patients with simple elbow dislocations was performed in tertiary-level hospitals from January 2010 to August 2019. Two orthopaedic surgeons separately assessed the initial plain radiographs and MRI scans. Osteochondral lesions were evaluated and categorized based on whether they were located (1) on the lateral side (posterolateral capitellum and radial head; type 1) or (2) on the medial side (posterior trochlea and anteromedial facet of the coronoid; type 2). The severity of the osteochondral lesions was assessed according to the Anderson classification.

Results:

Of the 43 patients, 21 (48.8%) presented with osteochondral lesions on MRI. The type 1 pattern of osteochondral lesions was the most frequently observed on MRI in patients with simple elbow dislocations (69.8% of cases), and these were confirmed by simple radiography. Posterolateral capitellum osteochondral lesions were found in 13 patients. Among them, 10 (76.9%) were advanced-stage lesions (stages III and IV according to the Anderson classification).

Conclusion:

Osteochondral lesions were found on MRI after simple elbow dislocations at a rate of 48.8%. Osteochondral lesions in the posterolateral capitellum were associated with an advanced stage. Clinically, these findings may help surgeons in the diagnosis of osteochondral lesions and in determining how to manage patients with the progression of arthritic changes.

MRI in acute simple elbow dislocations: correlation of preoperative imaging and intraoperative findings of collateral ligaments and associated soft tissue injuries

PURPOSE

The aim of our study was the evaluation of correspondence among collateral ligaments and other soft tissue injuries detected by MRI and by intraoperative findings in a consecutive series of patients treated for simple elbow dislocation.

METHODS

After clinical and MRI examination, 16 out of 59 consecutive patients with moderate or severe instability after simple elbow dislocation were addressed to surgical treatment. There were 14 men and 2 women. The mean age was 39.6 years (range 16-69 years).

RESULTS

MRI showed full-thickness lesion of MCL in 9/16 patients (53.3%) and partial lesion in 6/16 patients (40%), and in 1 case, the MCL was considered intact. On the lateral side, MRI showed complete injury of LCL in 7/16 patients (46.6%) and partial injury in 7/16 patients (40%). No lesions of LCL were observed in 2 patients (13.4%). MCL was surgically explored in all the patients. We observed 10/16 full-thickness lesions (62.5%) and 6/16 partial lesions (37.5%). LCL was surgically explored in 11/16 patients. We observed 6/11 full-thickness lesions (54.6%) and 5/11 partial lesions (45.4%). In 3 cases, associated soft tissue injuries were detected. The rate of concordance between MRI and surgical findings was 87.5% (14/16 cases) on the medial side and 90.9% (10/11 cases) on the lateral side.

CONCLUSION

Our study demonstrated that MRI is a reliable and useful tool to investigate collateral ligaments and soft tissue injuries around the elbow and to plan the most adequate surgical treatment.

Elbow Dislocation

This article is a brief overview of the elbow dislocations focusing on updates in treatment and rehabilitation protocols. The fight between obtaining elbow stability without leading to long-term elbow stiffness has been a continued focus in field of sports medicine. This article highlights advances made to help treat the injuries appropriately and obtain optimal patient outcomes.

Isolated displaced type II partial articular radial head fracture: correlation of preoperative imaging with intraoperative findings of lateral ulnar collateral ligament tear

BACKGROUND

The aim of this study was to determine the lateral ulnar collateral ligament (LUCL) injury associated with isolated radial head fracture (RHF) and the relationship of the ligament injury with the displacement of the fragment-loss of contact-in unstable displaced partial articular RHF in individuals without any history of ulnohumeral dislocation.

METHODS

We retrospectively identified 131 consecutive patients who underwent open reduction and internal fixation of isolated closed Mason type II RHF performed at our institution. We identified 3 subsets by the pattern of RHF and the position of the unstable fragment (anterior or posterior) relative to the capitulum humeri: displaced stable (group I), displaced anterior unstable (group II), and displaced posterior unstable (group III). Standard radiographs were obtained preoperatively and postoperatively. The pattern of lateral collateral ligament avulsion and its distribution were inferred from intraoperative records.

RESULTS

Preoperative radiographs of the 131 patients showed 101 nonseparated fractures (77%, group I) and 30 unstable fractures (23%). Anterior displacement of the fragment was found in 18 elbows (14%, group II) and posterior displacement in 12 (9%, group III). LUCL avulsion was found in 18 of 30 unstable RHFs (60%) and in 1 of 60 stable RHFs (1.6%).

CONCLUSION

RHF is a complex fracture often associated with soft tissue lesions. It is important to determine which structures need to be repaired to avoid complications that could lead to elbow instability. The RHF pattern and classification as stable or unstable can help the surgeon in the identification and treatment of LUCL lesions.

Anterior capsule re-attachment in terrible triad elbow injury with coronoid tip fracture

BACKGROUND

During the surgical treatment of terrible triad elbow injury (TTEI), the usefulness of re-attaching the anterior joint capsule when the coronoid tip is fractured remains unclear. The primary objective of this study was to assess potential benefits during surgery for TTEI of re-attaching the joint capsule when the coronoid tip is fractured.

HYPOTHESIS

Re-attaching the anterior joint capsule in TTEI with a fractured coronoid tip improves clinical and radiological outcomes and decreases the complication and revision rates.

MATERIALS AND METHODS

This single-centre retrospective study included patients who underwent surgery at the acute phase of TTEI with a fractured coronoid tip. In all patients, a physical examination and elbow radiographs were performed at least 1year after surgery. A statistical analysis was done to compare the groups with vs. without re-attachment of the anterior capsule and coronoid tip.

RESULTS

The study included 30 patients, 16 females and 14 males, with a mean age of 51years (range: 21-84years). Among them, 11 did and 19 did not undergo re-attachment. The two groups were comparable regarding demographic features and follow-up duration. No significant differences were found at last follow-up for flexion-extension motion arc (p=0.75), pronation-supination motion arc (p=0.3051), or the Mayo Elbow Performance Score (p=0.19). Radiographic evidence of humero-radial osteoarthritis was significantly more common in the absence of re-attachment (p=0.04), whereas no differences were evidenced regarding humero-ulnar osteoarthritis (p=0.73), the occurrence of subluxation or dislocation (p=0.43), or loosening of the radial head implant (p=0.47). The complication and revision rates were similar in the two groups.

CONCLUSION

In our experience, re-attaching the anterior capsule during the surgical treatment of TTEI with a coronoid tip fracture did not improve the clinical or radiographic outcomes after a mean follow-up of 54months.

LEVEL OF EVIDENCE

IV, retrospective study.