Magnetic resonance imaging findings in acute elbow dislocation: insight into mechanism

Return to play after UCL injury in gymnasts

BACKGROUND

Injuries to the ulnar collateral ligament (UCL) are commonly reported in traditional overhead sports. Conversely, there is a lack of evidence outlining management and return to play (RTP) outcomes for gymnasts. This study aimed to evaluate RTP and patient reported outcomes (PROs) in gymnasts after operative and non-operative treatment of UCL injuries.

METHODS

Gymnasts who presented with UCL injury and underwent operative and non-operative treatment were evaluated. Patient reported outcomes were collected via telephone: Conway-Jobe Scale, Kerlan-Jobe Orthopaedic Clinic Shoulder and Elbow (KJOC) Score, Mayo Elbow Performance (MEP) Score, and quick DASH (qDASH) and Timmerman-Andrews (TA) Elbow Score.

RESULTS

Nine patients met inclusion criteria and were available for follow-up. Five were initially treated operatively and four were initially treated non-operatively. The operative group initially consisted of three ulnar collateral ligament reconstructions (UCLR) and two UCL repairs with internal bracing. One patient crossed over to the operative group after failing non-operative treatment and underwent UCLR four months post injury. Overall, 66.7% and 100% of operatively and non-operatively treated gymnasts were able to return to play, respectively. At final follow-up, the operative groups' mean KJOC, MEP, TA, and qDASH scores were: 68.4 ± 7.7, 97.5 ± 2.7, 90.8 ± 10.7, and 1.9 ± 3.0, respectively. For the non-operative group, the mean scores were 67.4 ± 9.0, 71.7 ± 5.8, 71.7 ± 14.4, and 11.4 ± 9.9, respectively. Treatment satisfaction for the operative group was 81.7 ± 27.5 compared to 80.6 ± 34.5 in the non-operative group. Odds ratios indicated no differences between groups.

CONCLUSION

Both operative and non-operative interventions for UCL injuries in gymnasts can provide favorable outcomes with respect to return to play and subjective patient-reported outcomes. Further research is warranted to determine optimal treatment, especially regarding indications for operative vs. nonoperative treatment, of UCL injury based on injury severity and location in gymnasts.

LEVEL OF EVIDENCE

Case series; Level III Evidence.

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.

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.

Treatment strategies for simple elbow dislocation - a systematic review

BACKGROUND

Current treatment concepts for simple elbow dislocation involve conservative and surgical approaches. The aim of this systematic review was to identify the superiority of one treatment strategy over the other by a qualitative analysis in adult patients who suffered simple elbow luxation.

STUDY DESIGN

A systematic review in accordance with the PRISMA guidelines and following the suggestions for reporting on qualitative summaries was performed. A literature search was conducted using PubMed and Scopus, including variations and combinations of the following keywords: elbow, radiohumeral, ulnohumeral, radioulnar, luxation, and therapy. Seventeen studies that performed a randomized controlled trial to compare treatment strategies as conservative or surgical procedures were included. Reviews are not selected for further qualitative analysis. The following outcome parameters were compared: range of motion (ROM), Mayo Elbow Performance Score (MEPS), Disabilities of the Arm, Shoulder and Hand outcome measure (Quick-DASH), recurrent instability, pain measured by visual analog scale (VAS) and time to return to work (RW).

RESULTS

Early mobilization after conservative treatment strategies showed improved ROM compared to immobilization for up to 3 weeks after surgery with less extension deficit in the early mobilization group (16° ± 13°. vs. 19.5° ± 3°, p < 0.05), as well as excellent clinical outcome scores. Surgical approaches showed similar results compared to conservative treatment, leading to improved ROM (115 vs. 118 ± 2.8) and MEPS: 95 ± 7 vs. 92 ± 4.

CONCLUSION

Conservative treatment with early functional training of the elbow remains the first-line therapy for simple elbow dislocation. The surgical procedure provides similar outcomes compared to conservative treatment regarding MEPS and ROM for patients with slight initial instability in physical examination and radiographs. People with red flags for persistent instability, such as severe bilateral ligament injuries and moderate to severe instability during initial physical examination, should be considered for a primary surgical approach to prevent recurrent posterolateral and valgus instability. Postoperative early mobilization and early mobilization for conservatively treated patients is beneficial to improve patient outcome and ROM.

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.

High correlation of the subjective elbow value with Mayo Elbow Performance Score and Oxford Elbow Score in patients with elbow dislocation

Background

The purpose of this study was to analyze the correlation of the Subjective Elbow Value (SEV) with 2 widely used elbow scoring systems: Mayo Elbow Performance Score (MEPS) and Oxford Elbow Score (OES) in patients following elbow dislocation.

Methods

In this retrospective single-center study, patients who sustained an elbow dislocation between January 2008 and December 2019 and were at least 2 years out from injury were included. SEV, OES and MEPS were assessed and statistical correlation was calculated using Pearson's correlation coefficient.

Results

A total of 114 patients (61 male, 53 female) with a mean age of 47.1 years (range, 16-70) were analyzed following elbow dislocation. The mean SEV was 87.4% (95% confidence interval (CI) 84.2-90.7), mean MEPS was 88.1 (95% CI 85.1-91.0) points and mean OES was 40.0 (95% CI 38.4-41.7) points. Both MEPS (r = 0.710, P < .001), and OES (r = 0.764, P < .001) demonstrated high correlation with the SEV.

Conclusion

This study demonstrates that the SEV is a valid tool to assess overall status of the elbow in patients following elbow dislocations and presents an expressive but easy to perform addition to more complex scoring systems.

[Ligamentous elbow injuries-When is surgical treatment still indicated?]

The elbow joint is a hinge-type synovial joint and is the second most frequently dislocated joint in adults and the most frequently dislocated joint in children. To find the right treatment options a precise understanding of the injury pattern, anatomy, biomechanics and pathology (simple vs. complex dislocation) is essential for a good reconstruction of the function and to prevent chronic instability and pain. The differentiation between acute and chronic instability gives another variation in the treatment plan. According to the latest literature there are clear indications for surgery of a complex elbow dislocation, whereas for simple dislocations conservative treatment is preferentially recommended; however, when is the surgical treatment of a ligamentous elbow dislocation (still) indicated?

Dual Bracing for Ulnar Collateral Ligament Injuries Restores Native Valgus Laxity and Native Medial Joint Gapping of the Elbow

Background

Despite growing evidence on the role of the posterior ulnar collateral ligament (pUCL) in elbow stability, current ligament bracing techniques are mainly focused on the anterior ulnar collateral ligament (aUCL). A dual-bracing technique combines the repair of the pUCL and aUCL with a suture augmentation of both bundles.

Purpose

To biomechanically assess a dual-bracing approach addressing aUCL and pUCL for humeral-sided complete UCL lesions to restore medial elbow laxity without overconstraining.

Study Design

Controlled laboratory study.

Methods

A total of 21 unpaired human elbows (11 right, 10 left; 57.19 ± 11.7 years) were randomized into 3 groups to compare dual bracing with aUCL suture augmentation and aUCL graft reconstruction. Laxity testing was performed with 25 N applied 12 cm distal to the elbow joint for 30 seconds at randomized flexion angles (0°, 30°, 60°, 90°, and 120°) for the native condition and then for each surgical technique. A calibrated motion capture system was used for assessment, allowing the 3-dimensional displacement during the complete valgus stress cycle between the optical trackers to be quantified as joint gap and laxity. The repaired constructs were then cyclically tested through a materials testing machine starting with 20 N for 200 cycles at a rate of 0.5 Hz. The load was increased stepwise by 10 N for 200 cycles until displacement reached 5.0 mm or complete failure occurred.

Results

Dual bracing and aUCL bracing resulted in significantly (P = .045) less joint gapping at 120° of flexion compared with aUCL reconstruction. No significant differences in valgus laxity were found among the surgical techniques. Within each technique, there were no significant differences between the native and the postoperative state in valgus laxity and joint gapping. No significant differences between the techniques were observed in cycles to failure and failure load.

Conclusion

Dual bracing restored native valgus joint laxity and medial joint gapping without overconstraining and provided similar primary stability regarding failure outcomes as established techniques. Furthermore, it was able to restore joint gapping in 120° of flexion significantly better than aUCL reconstruction.

Clinical Relevance

This study provides biomechanical data on the dual-bracing approach that may help surgeons to consider this new method of addressing acute humeral UCL lesions.

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.

Overhead arm positioning in the rehabilitation of elbow dislocations: An in vitro biomechanical study

STUDY DESIGN

In vitro biomechanical study.

INTRODUCTION

Elbow stiffness is a common complication following elbow dislocation. Overhead exercises have been proposed to initiate early motion to reduce stiffness through employing gravity to stabilize the elbow. The implications of this position with regard to elbow kinematics after dislocation have not been reported.

PURPOSE OF THE STUDY

To determine the influence of the overhead position on elbow stability following combined medial and lateral collateral ligament (MCL and LCL) injuries.

METHODS

Passive and simulated active extension were performed on 11 cadaveric elbows with the arm in the overhead, dependent, and horizontal positions and with the forearm in pronation, neutral, and supination. Internal-external rotation (IER) and varus-valgus angulation (VVA) of the ulnohumeral joint were assessed for the intact elbow and after simulated MCL-LCL injury. Repeated-measures analyses of variance were conducted to analyze the effects of elbow state, arm position, forearm rotation, and extension angle.

RESULTS

During passive extension with the arm overhead, the pronated position resulted in more internal rotation than supination (-2.6 ± 0.7°, P = .03). There was no effect of forearm rotation on VVA. The overhead position increased internal rotation relative to the dependent position when the forearm was neutral (-8.5 ± 2.5°, P = .04) and relative to the horizontal position when the forearm was supinated (-12.7 ± 2.2°, P= .02). During active extension, pronation increased valgus angle compared to the neutral (+1.2 ± 0.3°, P= .04) and supinated (+1.5 ± 0.4°, P= .03) positions, but did not affect IER. There was no difference between active and passive motion with the arm overhead (P > .05).

DISCUSSION

Movement of the injured elbow in the overhead position most closely replicated kinematics of the intact elbow compared to the other arm positions.

CONCLUSIONS

Overhead elbow extension results in similar kinematics between an intact elbow and an elbow with MCL and LCL tears. As such, therapists might consider early motion in this position to reduce the risk of elbow stiffness after dislocation.

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.

The Effect of Acupuncture on Elbow Joint Sports Injuries Based on Magnetic Resonance Imaging

Purpose. Elbow joint injuries are extremely common in most athletes. Athletes’ chronic elbow injuries can involve multiple complex anatomical structures related to orthopedics. Therefore, it is of great significance to explore the characteristics of magnetic resonance (MR) images of chronic sports injuries of the elbow joint and the influence of acupuncture treatment on MR images and clinical symptoms. Methods. A total of 60 elbow joints of 39 athletes from 15-25 years old were selected for coronal, sagittal, and axial MR scans to observe the image characteristics; 60 elbow joints were randomly divided into acupuncture group and control group and observed changes in MR images and clinical symptoms after acupuncture treatment. Results. After acupuncture treatment, the clinical symptoms were significantly improved. MR images showed that the elbow joint effusion was reduced, and the bone marrow edema was reduced. The effective rate of acupuncture treatment is as high as 100%, while the effective rate of the control group is only 40%. Acupuncture treatment has significantly improved the range of motion of the elbow joint. Conclusion. Acupuncture treatment can significantly relieve athletes’ elbow joint pain and locking symptoms, improve joint range of motion, and is beneficial to recovery of special training and high-level competitive competitions. It is a sensitive, effective, and noninvasive method.

MRI of the Elbow: Interpretation of Common Orthopaedic Injuries

MRI is a valuable diagnostic tool that has become an essential part of an orthopaedic surgeon's practice. When acquired in the appropriate clinical setting, an MRI can direct patient management as surgical versus nonsurgical, guide surgical decision making, and even predict patient outcomes. The quality of MRI obtained and quality of the radiology report received varies. Ultimately, the orthopaedic surgeon must interpret the available imaging and apply these findings to treat the patient. The current day practicing orthopaedic surgeon should be familiar with interpreting common MRIs. Although subspecialized orthopaedic surgeons usually have experience and understanding of MRIs in their field, the general orthopaedic surgeon and those in-training will encounter the gamut of musculoskeletal MRIs. This review focuses on common injuries that can occur in the elbow and provides an approach to minimize missed findings.

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.

Analysis of Fracture Characteristic and Medial Collateral Ligament Injury Relationships in Terrible Triad Elbow Injuries

PURPOSE

The objectives of this study were to identify the relationship between fracture characteristics and medial collateral ligament (MCL) injuries in terrible triad injuries of the elbow.

METHODS

Between 2010 and 2018, 60 patients who underwent surgery for terrible triad elbow injuries were retrospectively reviewed. Using magnetic resonance imaging (MRI) assessments, patients were stratified into those who had intact or low-grade partial MCL tears (low-grade MRI-MCL group) and those who had high-grade partial or full-thickness MCL tears (high-grade MRI-MCL group). We also analyzed patients according to whether they underwent MCL repair surgery. Fractures of the radial head were assessed according to Mason's classification system and measurements of fracture fragment arc on axial cuts. Fractures of the coronoid processes were assessed according to the system of Regan and Morrey and measurements of coronoid process volumes.

RESULTS

Patients in the high-grade MRI-MCL group (28 patients) had a more comminuted and higher fragment arc of radial head fractures than those in the low-grade MRI-MCL group (32 patients) (143º ± 45º vs 119º ± 31º). However, the volume of coronoid fracture fragments was smaller in the high-grade MRI-MCL than in the low-grade MRI-MCL group (359 ± 325 mm³ vs 722 ± 448 mm³). The MCL repair group (22 patients) also had a more comminuted and higher fragment arc in radial head fractures (153º ± 44º vs 117º ± 31º) and a smaller coronoid process fracture volume (236 ± 224 mm³ vs 735 ± 419 mm³) than the non-MCL repair group (38 patients).

CONCLUSIONS

Our results demonstrated that high-grade MCL injuries are associated with comminuted and larger-sized radial head fractures, as well as smaller-sized coronoid process fractures in terrible triad injuries. In making a decision regarding surgical treatment, these fracture characteristics could help to predict the severity for MCL injury in terrible triad injuries.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Novel Radiographic Indexes for Elbow Stability Assessment: Part B-Preliminary Clinical Study

INTRODUCTION

The coronoid process plays a key-role in preserving elbow stability. Currently, there are no radiographic indexes conceived to assess the intrinsic elbow stability and the joint congruency. The aim of this study is to present new radiological parameters, which will help assess the intrinsic stability of the ulnohumeral joint and to define normal values of these indexes in a normal, healthy population.

METHODS

Four independent observers (two orthopaedic surgeons and two radiologists) selected lateral view X-rays of subjects with no history of upper limb disease or surgery. The following radiographic indexes were defined: trochlear depth index (TDI); anterior coverage index (ACI); posterior coverage index (PCI); olecranon-coronoid angle (OCA); radiographic coverage angle (RCA). Inter-observer and intra-observer reproducibility were assessed for each index.

RESULTS

126 subjects were included. Standardized lateral elbow radiographs (62 left and 64 right elbows) were obtained and analysed. The mean TDI was 0.46 ± 0.06 (0.3-1.6), the mean ACI was 2.0 ± 0.2 (1.6-3.1) and the mean PCI was 1.3 ± 0.1 (1.0-1.9). The mean RCA was 179.6 ± 8.3° (normalized RCA: 49.9 ± 2.3%) and the mean OCA was 24.6 ± 3.7°. The indexes had a high-grade of inter-observer and intra-observer reliability for each of the four observers. Significantly higher values were found for males for TDI, ACI, PCI and RCA.

CONCLUSION

The novel radiological parameters described are simple, reliable and easily reproducible. These features make them a promising tool for radiographic evaluation both for orthopaedic surgeons and for radiologists in the emergency department setting or during outpatient services.

LEVEL OF EVIDENCE

Basic Science Study (Case Series).

CLINICAL RELEVANCE

The novel radiological parameters described are reliable, easily reproducible and become handy for orthopaedic surgeons as well as radiologists in daily clinical practice.

Combined simple elbow dislocation and forearm joint injuries. A systematic review of the literature with injury patterns and current treatment rationale

INTRODUCTION

Recent studies have allowed a great improvement in understanding elbow and forearm traumatic injuries. Simple elbow dislocations combined with forearm injuries have been occasionally reported in the literature. The aim of this study was to detect the possible patterns of simple elbow dislocations and forearm fracture-dislocations, providing a classification scheme to guide surgical treatment.

MATERIALS AND METHODS

PubMed search was performed to find combination of simple elbow dislocation and forearm joint injury, between 2000 and 2020, including clinical studies and case report. All articles related to pediatric patient or with complex elbow dislocation were excluded. After identification, articles were analyzed for the description of injury patterns reported according to locker-based classification system of forearm joint injuries.

RESULTS

Finally, 15 articles were included. Most of the patients sustained high-energy trauma. According to locker-based classification system, simple elbow dislocation was combined with: MRUJ and DRUJ Galeazzi injury (2IR.3), PRUJ and MRUJ injury (1.2I), PRUJ and MRUJ injury with radial shaft fracture (1.2IR), PRUJ and MRUJ injury with ulnar shaft fracture (1.2 IU), PRUJ and MRUJ injury with radial and ulnar shaft fracture (1.2IRU), PRUJ MRUJ DRUJ Essex-Lopresti injury (1.2I.3), and PRUJ MRUJ DRUJ injury with radial shaft fracture (1.2IR.3). Thirteen out of 15 patients undergo surgical treatment. Clinical results were overall favorable.

CONCLUSIONS

Simple elbow dislocation combined with forearm joint injury is an uncommon traumatic pattern usually secondary to high-energy trauma. A thorough knowledge of elbow and forearm biomechanics, and classification of anatomical lesion is mandatory for a successful treatment.

Nonsurgical Management of Ulnar Collateral Ligament Injuries

Ulnar collateral ligament (UCL) injuries are a common source of pain and disability in the overhead athlete and often result in notable loss of time from competition. Over the past 10 to 15 years, the prevalence of UCL injury and reconstruction has undergone a dramatic increase, making it imperative to determine which patients may benefit from a nonsurgical regimen. Nonsurgical treatment involves a multidisciplinary approach of rehabilitation with tailored physical therapy programs and, in certain cases, biologic adjuncts. Physical therapy protocols should focus on strengthening the periscapular muscles, rotator cuff, core musculature, and flexor pronator mass to help stabilize the injured elbow and prevent injury recurrence before the initiation of a progressive throwing program. The implementation of injury prevention programs has shifted the focus from just the elbow and have included the shoulder, legs, and core in an effort to help decrease the stress on the upper extremity. In addition, biologic therapies such as platelet-rich therapy are promising modalities to augment the conservative treatment of UCL injuries but remain under investigation. The purpose of this study is to review available strategies and outcomes for conservatively treating UCL injuries.

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.

Treatment of elbow instability: state of the art

The elbow is a congruent joint with a high degree of inherent stability, provided by osseous and soft-tissue constraints; however, when substantial lesions of these stabilising structures happen, instability of the elbow occurs. Significant improvements in surgical elbow instability diagnosis and treatment have been recently introduced both for acute and chronic cases. Specific stress tests, recently introduced in the clinical practice, and different imaging techniques, both static and dynamic, allow assessment of the elbow stabilisers and detection of the instability direction and mechanism even in subtle forms. Many surgical techniques have been standardised and surgical instruments and devices, specifically dedicated to elbow instability treatment, have been developed. Specific rehabilitation protocols have been designed to protect the healing of the elbow stabilisers while minimising elbow stiffness. However, despite the progress, surgical treatments can be challenging even for expert surgeons and the rate of persistent instability, post-traumatic arthritis, stiffness and pain can be still high especially in most demanding cases. The biology of the soft-tissue healing remains one of the most important aspects for future investigation. If future research will help to understand, correct or modulate the biological response of soft-tissue healing, our confidence in elbow instability management and the reproducibility of our treatment will tremendously improve. In this paper, the state of the art of the current knowledge of elbow instability is presented, specifically focusing on modern surgical techniques used to solve instability, with repair or reconstruction of the damaged elbow stabilisers.

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.

Elbow Instability: Evaluation and Treatment

Acute elbow dislocations are commonly seen in clinical practice, and attention to management principles and strategies can help facilitate improved outcomes. Patients may present with simple elbow dislocation, in which nonoperative treatment is highly successful. Alternatively, fracture dislocations can be sometimes easily managed but frequently are associated with the need for surgical intervention and operative and postoperative challenges.

Rehabilitation of Elbow Instability

The elbow is the second most commonly dislocated major joint in adults with estimated incidence of 5 dislocations per 100,000 persons per year. A comprehensive understanding of elbow anatomy and biomechanics is essential to optimize rehabilitation of elbow injuries. This allows for implementation of a systematic therapy program that encourages early mobilization within a safe arc of motion while maintaining joint stability. To optimize outcomes, close communication between surgeon and therapist is necessary to allow for implementation of an individualized rehabilitation program. This article reviews key concepts that enable the clinician to apply an evidence-informed approach when managing elbow instability.

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.

Soft tissue injury patterns in posteromedial rotatory instability with dislocation compared with posteromedial dislocation of the elbow joint

BACKGROUND

We sought to determine injury mechanisms and soft tissue injury patterns of dislocation caused by posteromedial rotatory instability (PMRI) and simple posteromedial (PM) dislocation of the elbow joint that appear similar on simple radiographs.

METHODS

In this retrospective case-series study, we reviewed 13 patients with PMRI dislocation and 10 patients with simple PM dislocation. Three-dimensional computed tomography and magnetic resonance imaging were performed in both groups. The ulnar collateral ligament, lateral collateral ligament complex (LCLC), overlying extensor muscle, and locus of bone contusion were identified. The direction of dislocation was categorized into the pure-posterior or PM type by simple radiographs.

RESULTS

The LCLC was completely ruptured in both groups. A completely torn ulnar collateral ligament was observed in 3 patients (23%) in the PMRI dislocation group and 9 patients (90%) in the simple PM dislocation group (P = .005). Regarding injury patterns of the LCLC and overlying extensor muscle, the distraction type was found in 10 patients (77%) and the stripping type was found in 3 patients (23%) in the PMRI dislocation group, whereas all patients (100%) in the simple PM dislocation group had the distraction type (P = .103). Bone contusion was observed at the posterolateral olecranon in 2 patients (15%) in the PMRI dislocation group and at the PM olecranon in 4 patients (40%), posterolateral olecranon in 1 (10%), posterior olecranon in 1 (10%), and PM-posterolateral olecranon in 1 (10%) in the simple PM dislocation group (P = .008). In the PMRI dislocation group, 7 patients (54%) had the PM type and 6 (46%) had the pure-posterior type.

CONCLUSIONS

Simple PM and PMRI dislocations of the elbow joint might have different soft tissue injury characteristics because of different injury mechanisms.

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.

The Acutely Injured Elbow

The acutely injured elbow can present as a diagnostic challenge, encompassing a spectrum of conditions that involve the various osseous and soft tissue structures of this complex joint. Imaging plays a vital role in the management of these patients by providing an accurate interpretation of the underlying trauma sustained, which can have important implications on the preservation of joint function and stability. This article examines the mechanisms, patterns, classifications, and imaging findings of acute elbow injuries, providing key concepts for the radiologist in the interpretation of these injuries.

Primary Ligament Repair for Acute Elbow Dislocation

The elbow is the second most common site for joint dislocation after the shoulder. Elbow dislocations are classified according to the direction of dislocation, with most (80%) being posterolateral. A spectrum of soft-tissue injury may also be present, depending on the direction of dislocation and the energy applied. Most dislocations of the elbow can be treated nonoperatively, but recurrent instability and/or stiffness occur in up to 10% and 40% of patients, respectively. The aim of early surgical stabilization is to prevent these long-term complications. To avoid overtreatment, magnetic resonance imaging is used to identify patients at a greater risk of complications by determining the grade of soft-tissue injury. Those with grade-3 or 4 injuries are managed with fluoroscopic examination under anesthesia. (1) The patient is positioned supine. Fluoroscopic examination is performed with the elbow in full extension and in 30° of flexion. Varus stress is applied with the forearm in pronation. If >10° of joint opening is found, open surgical repair of the lateral ligament complex and common extensor origin is performed. (2) A 5-cm incision is made using a direct lateral approach centered on the lateral epicondyle. The tough lateral fascia may be intact and should be incised in line with the anconeus interval. (3) A rent in the common extensor origin may be found, which can be used for the approach; otherwise, proceed with a Kocher approach to identify the sleeve avulsion of the lateral ligament complex from the humerus. (4) A number-2 synthetic braided suture is used to whip-stitch the lateral ulnar collateral ligament, which is repaired to the lateral epicondyle with use of a bone anchor. The trailing suture ends from the anchor are used to repair the common extensor tendon origin with use of a Mayo needle. (5) With the forearm in supination to externally rotate the humerus and lock the shoulder, valgus instability is assessed with the elbow in full extension and in 30° of flexion. If the medial joint line opens >10°, repair the medial structures in the same manner as the lateral ligament complex through an incision posterior to the medial epicondyle while protecting the ulnar nerve. (6) The patient is referred to physiotherapy for immediate hourly overhead exercises. This approach should prevent complications of recurrent instability or stiffness, as early results have been encouraging with no complications recorded.

Approach to Medial Elbow Pain in the Throwing Athlete

PURPOSE OF REVIEW

Injury to the ulnar collateral ligament is the most common, significant injury affecting the medial elbow of the overhead athlete. However, there are many other significant sources of pathology that should be considered. This review seeks to present a broad range of conditions that providers should consider when evaluating the overhead athlete with medial elbow pain.

RECENT FINDINGS

Recent biomechanical studies have deepened understanding of the anatomy and function of the anterior bundle of the ulnar collateral ligament germane to the overhead athlete. Orthobiologics hold potential for expanding the role of non-operative treatment for ulnar collateral ligament injuries. In addition to injury to the ulnar collateral ligament, providers should be prepared to diagnose and treat valgus extension overload, proximal olecranon stress fracture, ulnar nerve pathology, common flexor - pronator mass injury, and, in adolescents, medial epicondylar avulsion, when managing medial elbow pain in the overhead athlete.

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

BACKGROUND

The elbow is the second most commonly dislocated joint. Stability depends on the degree of soft tissue injury, with 2 proposed patterns, one starting laterally and the other medially. The purpose of this study was to describe the injured structures observed in magnetic resonance images (MRIs) in a prospective cohort of simple elbow dislocations.

METHODS

We evaluated 17 consecutive cases of simple elbow dislocations. Two musculoskeletal radiologists assessed the initial x-ray images and MRIs performed for all elbows. Radiologists evaluated the following soft tissue structures: medial collateral ligament complex (MCL), flexor-pronator muscle mass origin, anterior capsule (AC), posterior capsule, lateral collateral ligament complex (LCL), and extensor muscle mass origin. The radiologists were blinded to the study hypothesis.

RESULTS

The initial radiographs in 16 patients showed the dislocation was posterolateral in 12, posterior in 3, and posteromedial in 1. We observed complete AC tear in 12 patients, MCL in 10, and LCL in 9. The inter-rater reliability for the radiologists was 0.70 (substantial) for MRI.

CONCLUSIONS

In our series after simple elbow dislocation, complete AC tears were most common, followed by MCL and LCL tears. No single mechanism-related soft tissue injury pattern of simple elbow dislocation was observed, and different grades of soft tissue injury exist.

Ligaments injuries check-up and assessment of their healing potential in simple posterolateral elbow dislocation: about 25 cases

INTRODUCTION

Elbow dislocation can lead to instability and stiffness of the elbow. The main goal of this study was to list the initial elbow ligaments injuries caused by simple posterolateral elbow dislocations. The secondary goals were to assess ligament healing 2 months after the initial dislocation, to research a correlation between ligaments injuries and clinical course, and to search for predictive factors of instability.

PATIENTS AND METHODS

Patients who had simple posterolateral elbow dislocation for the first time between January 2015 and May 2016 were included. Each patient had an MRI scan of their traumatised elbow on the day of the dislocation and then again 2 months later. The assessment was performed thanks to a clinical examination and calculation of functional recovery scores. The Mann-Whitney U test was used to research a correlation between the healing of ligaments injuries and clinical course.

RESULTS

Twenty-five patients were included in the study. The initial MRI scans showed 70% and 54% ligament rupture, respectively, for the anterior band (ant MCL) and the posterior band (post MCL) of the medial collateral ligament (MCL), as well as 79% for the ulnar (ULCL) and 50% for the radial (RLCL) lateral collateral ligaments. The healing rate 2 months after dislocation was fairly low from 18% for the ULCL up to 41% for the anterior band of the MCL. No correlation was found between the ligament healing noticeable on MRI scans and clinical course. No elbow instability was diagnosed during the 4-month follow-up.

CONCLUSION

Elbow dislocation is particularly damaging for ligaments. There is no predominance on medial or lateral ligament for rupture. The low healing rate 2 months after the initial dislocation could be explained by performing a follow-up MRI scan too early.

[Acute and chronic instability of the elbow joint]

Elbow dislocations are frequent and present with a broad spectrum of subsequent ligamentous and soft tissue injuries. Beside clinical examination, fluoroscopy, ultrasound and magnetic resonance imaging (MRI) can specify the extent of the injuries and provide a foundation for decision-making between conservative and operative treatment. This article highlights the basic underlying biomechanics and anatomy, discusses the trauma mechanisms and presents clinical and imaging diagnostic procedures. Treatment algorithms for conservative and surgical treatment are presented in detail. In addition to acute instability, chronic instability of the elbow has recently been recognized as the cause of a large variety of symptoms, often resulting in significant functional impairment. The most commonly used techniques for reconstruction of the medial and lateral collateral ligaments and the rehabilitation protocols are described in detail.

Determination of Elbow Laxity in a Sequential Soft-Tissue Injury Model: A Cadaveric Study

BACKGROUND

The objective of our study was to analyze, under fluoroscopy, joint angulation of uninjured elbows and elbows with distinct induced collateral ligament injury.

METHODS

Twelve elbow specimens were tested for varus and valgus joint angulation using 4 different examination methods (application of both varus and valgus stress by each of 2 examiners [Examiner 1 and Examiner 2] and application of 1 and 2 Nm of torque using a calibrated electric force scale) in 4 elbow positions (in full extension with 90° of supination and 90° of pronation, and in 30° of flexion with 90° of supination and 90° of pronation). Six elbow specimens were examined under varus stress at each of 5 sequential stages: (1) intact, (2) transection of the lateral ulnar collateral ligament (LUCL), (3) complete transection of the lateral collateral ligament complex (LCLC), (4) transection of the anterior aspect of the capsule (AC), and (5) transection of the medial collateral ligament (MCL). An additional 6 elbow specimens were examined under valgus stress at 5 sequential stages: (1) intact, (2) transection of the anteromedial collateral ligament (AML), (3) complete transection of the MCL, (4) transection of the AC, and (5) transection of the LCLC. Examinations under fluoroscopy were made to measure the joint angulation. Intraclass correlation coefficients (ICCs) were calculated.

RESULTS

Testing of the intact elbow specimen by both examiners showed a joint angulation of <5°. Transection of the LUCL led to a varus joint angulation of 4.3° to 7.0°, and transection of the AML resulted in a valgus joint angulation of 4.9° to 8.8°. Complete dissection of the respective collateral ligament complex resulted in a joint angulation of 7.9° to 13.4° (LCLC) and 9.1° to 12.3° (MCL), and additional transection of the AC led to a joint angulation of >20° in some positions in both the medial and the lateral series. Under varus stress, elbow dislocations occurred only after dissection of the LCLC+AC (26% of the examinations) and additional dissection of the MCL (59%). Under valgus stress, elbow dislocations occurred only after dissection of the MCL+AC (30%) and additional dissection of the LCLC (47%). Very good to excellent ICCs were found among Examiners 1 and 2 and the tests done with the standardized torques at stages 1 through 4.

CONCLUSIONS

Dynamic fluoroscopy makes it possible to distinguish among different stages of collateral ligament injury of the elbow and therefore might be helpful for guiding treatment of simple elbow dislocations.

CLINICAL RELEVANCE

Assessment of collateral ligament injury with varus and valgus stress testing under fluoroscopy is an easily available method and is often used as the imaging modality of choice to determine the degree of elbow laxity. The technique and results described in this study should form the basis for additional clinical studies.

The Posterior Bundle's Effect on Posteromedial Elbow Instability After a Transverse Coronoid Fracture: A Biomechanical Study

PURPOSE

There has been increased interest in the role of the posterior bundle of the medial collateral ligament (pMUCL) in the elbow, particularly its effects on posteromedial rotatory stability. The ligament's effect in the context of an unfixable coronoid fracture has not been the focus of any study. The purposes of this biomechanical study were to evaluate the stabilizing effect of the pMUCL with a transverse coronoid fracture and to assess the effect of graft reconstruction of the ligament.

METHODS

We simulated a varus and internal rotatory subluxation in 7 cadaveric elbows at 30°, 60°, and 90° elbow flexion. The amount of ulnar rotation and medial ulnohumeral joint gapping were assessed in the intact elbow after we created a transverse coronoid injury, after we divided the pMUCL, and finally, after we performed a graft reconstruction of the pMUCL.

RESULTS

At all angles tested, some stability was lost after cutting the pMUCL once the coronoid had been injured, because mean proximal ulnohumeral joint gapping increased afterward by 2.1, 2.2, and 1.3 mm at 90°, 60°, and 30°, respectively. Ulnar internal rotation significantly increased after pMUCL transection at 90°. At 60° and 30° elbow flexion, ulnar rotation increased after resection of the coronoid but not after pMUCL resection.

CONCLUSIONS

An uninjured pMUCL stabilizes against varus internal rotatory instability in the setting of a transverse coronoid fracture at higher flexion angles. Further research is needed to optimize graft reconstruction of the pMUCL.

CLINICAL RELEVANCE

The pMUCL is an important secondary stabilizer against posteromedial instability in the coronoid-deficient elbow. In the setting of an unfixable coronoid fracture, the surgeon should examine for posteromedial instability and consider addressing the pMUCL surgically.

Elbow Fractures with Instability: Evaluation and Treatment Strategies

The treatment goals of elbow fracture dislocations are congruent reduction of the ulnohumeral and radiocapitellar joints, stable fixation of the proximal ulna, stable fixation or arthroplasty of the radial head, and soft tissue repair. Fracture dislocations occur in patterns, and recognition of these patterns help guide surgical treatment. In patients with persistently unstable fractures after standard fixation, additional temporary joint spanning implants are useful to protect repairs.

Acute and overuse elbow trauma: radio-orthopaedics overview

The correct management of acute, subacute and overuse-related elbow pathologies represents a challenging diagnostic and therapeutic problem. While major trauma frequently requires a rapid surgical intervention, subluxation and minor trauma allow taking more time for diagnostics and planning the correct elective treatment after careful clinical and radiological investigation. In these conditions, communication between orthopaedic surgeon and radiologist allow to create a detailed radiology report, tailored to the patient's and surgeon's needs and optimal to plan proper management. Imaging technique as X-Ray, CT, US, MRI, CTA and MRA all belong to the radiologist's portfolio in elbow diagnostics. Detailed knowledge of elbow pathology and its classification and of the possibilities and limits of each imaging technique is of crucial importance to reach the correct diagnosis efficiently. The aim of this review is to present the most frequent elbow pathologies and suggest a suitable diagnostic approach for each of them.

[Ulnar collateral ligament reconstruction of the elbow in posttraumatic and chronic ligament instability]

OBJECTIVE

Restoration of ulnar elbow stability in cases of posttraumatic and chronic ulnar ligament instability.

INDICATIONS

Symptomatic therapy-resistant ulnar ligament instability of the elbow.

CONTRAINDICATIONS

Arthrofibrosis and high-grade elbow arthrosis.

SURGICAL TECHNIQUE

Anatomical reconstruction of the ulnar collateral ligament (UCL) with autologous tendon graft (tendons of the palmaris longus muscle and gracilis muscle) in implant-free docking technique.

POSTOPERATIVE MANAGEMENT

A cast for 1 week, then 5 weeks orthesis with limitation of complete extension and flexion; full weight bearing after 3 months.

RESULTS

After 2 years 90% of the patients are able to return at an equal level of activity. The overall complication rate is 10.4%. The most common complication is ulnar nerve neurapraxia in 7.8% of the patients.

Avoiding Tommy John Surgery: What Are the Alternatives?

The number of ulnar collateral ligament (UCL) reconstructions being performed has risen sharply in recent years, most notably in the young amateur athlete. While successful outcomes have been reported with reconstruction, the surgery and the associated rehabilitation timeline may be difficult for the nonelite athlete to incur. Return-to-play expectations, along with level of competition, should help guide surgeons in exploring management options. While reconstruction remains a mainstay, focused research exploring nonreconstructive options has expanded. This review discusses the clinical approach to those with UCL injury, including current support for rehabilitation, biologic strategies, and available repair or augmentation alternatives.

[Chronic ligamentous instability of the elbow]

BACKGROUND

Chronic ligamentous instability of the elbow is an important pathology as it is accompanied with pronounced dysfunction. Moreover, it represents an established risk factor for the development of osteoarthritis. Posterolateral rotatory instability (PLRI) caused by insufficiency of the lateral collateral ligament (LCL) is the most common type of chronic elbow instability and is usually a sequel of traumatic elbow dislocation. Chronic overload can lead to insufficiency of the ulnar collateral ligament (UCL) with subsequent valgus instability, especially in overhead athletes.

DIAGNOSTICS

Subjective instability and recurrent elbow dislocations are not always the main symptoms but elbow instability is instead often characterized by pain and secondary joint stiffness. Many clinical tests are available yet eliciting them can be difficult and inconclusive. A "drop sign" on lateral radiographs as well as the detection of collateral ligament injuries and joint incongruity on MRI scans can support the suspected diagnosis. In some cases, instability can only be verified by diagnostic arthroscopy.

TREATMENT

Reconstruction of the lateral ulnar collateral ligament (LUCL) for treatment of PLRI generally leads to good clinical results, yet recurrent instability remains an issue and has been reported in 8 % of cases. UCL reconstruction for chronic valgus instability leads to a return-to-sports rate of about 86 % in the overhead athlete. Ulnar neuropathy, which is seen in approximately 6 % of patients, represents the most common complication. On the rare occasion of multidirectional instability, the box-loop technique can be used for simultaneous reconstruction of the LUCL and UCL with a circumferential graft. 15 cases with promising results have been reported in literature thus far.

[Elbow dislocation fractures]

The treatment of complex elbow dislocation fractures is a challenge to both the treating surgeon as well as to the patient due to the complex bony and soft tissue anatomy of the joint. In order to establish an expedient treatment algorithm, all osseous and ligamentous injuries need to be thoroughly assessed. Furthermore, a detailed knowledge of the joint-stabilizing structures, practicable surgical approaches as well as the possible techniques for fracture fixation and/or arthroplasty are essential to facilitate early rehabilitation of the elbow and avoid injury-related complications. Any unnecessary delay in treatment of this complex injury can result in posttraumatic functional disorders, recurrent instability and secondary arthrosis. In conclusion, the goals of surgical treatment must be the correct restoration of the joint anatomy and stability as the prerequisites for any successful treatment of elbow fracture dislocations in order to enable early motion of the joint.

Simple elbow dislocation

The elbow is the second most commonly dislocated major joint in adults. Good long-term outcomes have been reported after non-operative management; however, a small proportion (<10%) of patients have a poor outcome and some do require surgical intervention. A review of the anatomy, pathoanatomy, management and outcomes of simple elbow dislocations is presented. Emphasis is placed on emerging concepts regarding the soft tissue injury, the stabilising structures that are injured, the sequence and mechanism of injury and the relationship to elbow stability. The benefits of nonsurgical and surgical management are discussed and a treatment algorithm based on the pathoanatomy is proposed.