Classification and evaluation of recurrent instability of the elbow

Anatomical considerations, diagnosis, and treatment of medial and posterolateral elbow rotatory instability in athletes: an arthroscopic perspective and literature review

PURPOSE

Elbow joint instability results from the disruption of one or more stabilizing anatomical structures. The two most common forms of instability are posterolateral rotatory instability (PLRI) and medial elbow instability (MEI), particularly in athletes. This review aims to explore the anatomical foundations, diagnostic methods, and therapeutic approaches for PLRI and MEI in athletes.

METHODS

A comprehensive literature review was performed to investigate the study objective.

RESULTS

Regarding the anatomical background, the primary stabilizing structures of the elbow joint include the humeroulnar joint (trochlea, olecranon, and coronoid process), the medial collateral ligament (MCL), and the lateral ulnar collateral ligament (LUCL). PLRI is primarily caused by LUCL insufficiency, while MEI results from MCL dysfunction. A thorough clinical evaluation, combined with advanced imaging-magnetic resonance imaging (MRI) or MR arthrography is essential for an accurate diagnosis. For high-level athletes, surgical intervention is often required, with the timing and type of surgery tailored to the athlete's specific needs, expectations, and the chronicity of the injury.

CONCLUSION

PLRI and MEI present diagnostic and therapeutic challenges, especially in athletes. Advanced imaging and clinical evaluation are crucial for the diagnosis. Surgical intervention, particularly arthroscopy, is often required for optimal outcomes.

Arthroscopic ligament débridement combined with tendon repair benefits lateral collateral ligament lesions in recalcitrant lateral epicondylitis patients: a retrospective comparative study

BACKGROUND

Untreated lateral collateral ligament (LCL) lesions in recalcitrant lateral epicondylitis (RLE) may cause residual pain and progressed to elbow instability. However, there is not enough research on the effect of arthroscopic treatment of combined LCL degenerative lesions without instability in RLE patients. The purpose of this study was to 1) evaluate the clinical and radiological results of RLE patients with LCL degenerative lesions without instability who received arthroscopic LCL débridement and extensor carpi radialis brevis (ECRB) repair, and 2) compare clinical outcomes between RLE patients with LCL degenerative lesion and those without, which received ECRB repair alone.

METHODS

A retrospective study was performed in which 31 RLE patients with LCL degenerative lesions without instability, who underwent arthroscopic LCL débridement with shaver and radiofrequency combined with ECRB repair with suture anchor arthroscopically between September 2014 and September 2022, comprised the LCL group. The control group (N = 31) was matched 1:1 for age ( ±5 years), sex, involved side, hand dominance, body mass index, working status, duration of symptoms, steroid/platelet-rich plasma injections and follow-up time. Thirty-one matched RLE patients without LCL lesions, who underwent arthroscopic ECRB repair with suture anchor alone. The visual analog scale, the Patient-Rated Tennis Elbow Evaluation, the Mayo Elbow Performance Score, and the Disability of the Arm, Shoulder, and Hand questionnaire were evaluated and compared between 2 groups at preoperative and follow-up periods (at 3, 6, and 12 months follow-up). The time duration of back to work was also compared between 2 groups. Magnetic resonance imaging (MRI) in LCL group was collected.

RESULTS

There were no significant differences in any clinical outcome at each follow-up time between the 2 groups (P > .05 for all). There were no significant differences in time duration of return to work between LCL group and control group (9.4 ± 3.0 weeks vs. 8.9 ± 3.4 weeks; P = .529). There were 26 patients showed abnormal MRI signal of LCL in LCL group preoperatively. At 12 months follow-up, none of them showed abnormal MRI signal. Additionally, there was no complication found in LCL group at the 12 months follow-up.

CONCLUSION

In patients with RLE and degeneration of an intact LCL without instability, débridement of the LCL lesion while repairing the ERCB does not seem to impair outcomes in short-term follow-up when compared to patients with RLE treated by repair of the ERCB with intact LCLs.

Subjective grade of apprehension during the pivot-shift test reflects patient-reported outcomes more than conventional pivot-shift test grade after ACL reconstruction

PURPOSE

To investigate whether the pivot-shift test reflects patient-reported outcomes 1 year after anterior cruciate ligament (ACL) reconstruction based on a multicentre prospective cohort study.

METHODS

This study included patients who underwent primary ACL reconstruction using the hamstring tendons. The pivot-shift test grades were determined according to the International Knee Documentation Committee (IKDC) form as 0, 1+, 2+ or 3+. In addition, patients' subjective apprehension during the pivot-shift test were classified as 0 (no-apprehension), 1+ (mild-apprehension), 2+ (moderate-apprehension) or 3+ (severe-apprehension). In this study, a positive pivot-shift test was defined as grade 1+ or higher.

RESULTS

A total of 837 patients were enroled in this study. One year postoperatively, there was no significant difference in the Knee injury and Osteoarthritis Outcome Score (KOOS), IKDC score, Lysholm knee scale and Tegner activity scale between the positive (118 patients) and negative (719 patients) groups of the conventional IKDC grading of the pivot-shift test. However, when divided into two groups based on the apprehension grading of the pivot-shift test after surgery, the postoperative scores were significantly lower in the apprehension-positive group (114 patients) than those in the apprehension-negative group (723 patients) on the Tegner activity scale and KOOS Symptom, Sports/Rec and Quality of Life subscales.

CONCLUSIONS

Patients' subjective apprehension during the pivot-shift test after ACL reconstruction was significantly associated with the postoperative Tegner activity scale and three subscales of the KOOS. However, there was no association between the conventional IKDC grading of the pivot-shift test and any patient-reported outcomes postoperatively.

LEVEL OF EVIDENCE

Level II.

Diagnostic Musculoskeletal Ultrasound for the Evaluation of the Lateral Elbow: Implications for Rehabilitation Providers

Musculoskeletal ultrasound (MSKUS) has emerged as a valuable diagnostic tool in the evaluation and management of lateral elbow pathologies. This imaging modality provides high-resolution, dynamic visualization of superficial soft tissue structures, making it particularly advantageous for assessing conditions such as lateral epicondylitis (tennis elbow), ligamentous injuries, radial tunnel syndrome, and other common disorders. This article reviews the utility of MSKUS for rehabilitation providers, focusing on its role in accurately identifying pathoanatomical changes, guiding treatment strategies, and monitoring therapeutic outcomes. Specific emphasis is placed on the integration of diagnostic ultrasound in clinical practice, imaging techniques, and its advantages compared to other modalities. By enhancing diagnostic accuracy and facilitating targeted interventions, MSKUS serves as a critical adjunct in the comprehensive care of lateral elbow conditions.

Arthroscopic evaluation for posterolateral rotatory instability of the elbow

Objective

The purpose of this study was to evaluate the sensitivity of three arthroscopic techniques for intraoperative assessment of posterolateral rotatory instability (PLRI).

Methods

The study was performed using six fresh frozen cadaveric upper extremities. The three arthroscopic tests were the modified ulnohumeral drive through test, the annular drive through test, and proximal radioulnar joint instrumentation. Sequential soft tissue sectioning was performed to create four stages of instability: baseline, transection of the anterior half of the lateral collateral ligament complex (i.e., the radial collateral ligament), transection of the posterior half of the LCL complex (i.e., the lateral ulnar collateral ligament), and finally the release of the common extensor origin. Each test was repeated with the elbow at 90-degrees flexion in neutral rotation and at 45-degrees extension in full supination.

Results

Each test appropriately identified loss of the lateral ulnar collateral ligament. The modified ulnohumeral drive through test and the annular drive through test were most sensitive for loss of the radial collateral ligament. Elbow position did not affect test sensitivity.

Conclusions

Each of the tests identified PLRI with high sensitivity, regardless of elbow position. The ulnohumeral and annular ligament drive through tests were more sensitive for radial collateral ligament disruption.

MRI of the Elbow - Update 2024

Elbow pain can result in significant morbidity. MRI can help diagnosing the cause of elbow pain.Based on a systematic literature search as well as knowledge gained through frequent participation in conferences dedicated to advances in musculoskeletal imaging, this review aims to give a brief overview of normal anatomy and common pathologies of tendons and ligaments of the elbow on magnetic resonance imaging.Stabilization of the elbow joint is provided by osseous structures and passive ligamentous and active muscular support. Loss of these important stabilizers, due to trauma and overuse, can result in elbow instability. Additional MR views or intra-articular contrast media can be useful for the detection of specific pathologies.MRI is frequently used to detect posttraumatic or chronic conditions, which can lead to posterolateral or posteromedial elbow instability. Knowledge of normal anatomy, variants, pathologies, as well as appropriate imaging is crucial to make the diagnosis. · Epicondylitis occurs due to chronic degeneration with tendinosis and partial tendon tearing and is not related to an acute inflammatory reaction.. · Posterolateral or posteromedial elbow instability can be the result of trauma with loss of passive ligamentous and active muscular stabilization.. · The most common elbow instability is posterolateral rotatory instability with the LUCL being the most important stabilizer affected by injury.. · Schinnerl C, Weber M, Benninger E et al. MRI of the Elbow - Update 2024. Fortschr Röntgenstr 2024; DOI 10.1055/a-2416-1491.

Monteggia Fracture Dislocation

SUMMARY

Monteggia fracture is a complex fracture consisting of a proximal ulna fracture with a dislocation of the radial head. This review article highlights the relevant anatomy, clinical evaluation, classification, surgical management, recent innovation, and advancements with treating these injuries. A thorough understanding of these fractures allows for detailed operative plans and reconstitution of normal anatomy.

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.

Management of Pediatric Elbow Fractures and Dislocations

Pediatric elbow fractures and dislocations have always been a challenge from a diagnostic and therapeutic point of view, primarily due to the complex nature of the pediatric elbow, especially its developmental anatomy. They must be diagnosed and treated on time to prevent numerous complications with long-term consequences. With the development of radiology and pediatric surgery and orthopedics, as well as the development of modern osteosynthesis materials, concerning current scientific and professional knowledge, the outcomes are getting better, with fewer acute and chronic complications. This comprehensive review aims to provide clinicians current knowledge about pediatric elbow fractures and dislocations so that in daily practice they have as few doubts as possible with the best possible treatment outcomes.

A clinical review of elbow ligament repairs and reconstructions in the acute and chronic settings

Background

The ligamentous and osseous structures of the elbow joint are the major contributors to its inherent stability and damage to any of these structures can result in elbow instability. The aim of this study is to present objective and subjective outcomes following ligament repairs and/or reconstructions for acute elbow instability and chronic elbow instability.

Methods

This study included patients who underwent an elbow ligament repair and/or reconstruction for acute or chronic elbow instability. We performed a comprehensive retrospective data analysis of the patient's files, followed by a clinical examination and X-ray of these patients.

Results

We identified 12 acute stabilizations and 22 stabilizations for chronic instability. Patients who underwent stabilization for chronic instability had statistically significant improvements in their preoperative flexion and extension; 14.8 ± 6.4° and 5.9 ± 2.5°. Patients with chronic instability achieved better extension-flexion and pronation-supination arcs compared with their acute instability counterparts and this reached statistical significance. When the elbow pain and function scores were compared, we found stabilizations in the acute setting had better outcomes. There were two cases of postoperative instability, one in the acute instability group and one in the chronic instability group.

Conclusion

This study provides evidence for elbow ligament repairs and reconstructions in both acute and chronic settings. It is an effective way of stabilizing the elbow joint in chronic instability patients, and results in an improvement in their overall range of motion. These patients achieved a greater range of motions compared with their acute instability counterparts.

Anconeus-sparing minimally invasive approach for lateral ulnar collateral ligament reconstruction using a triceps tendon autograft is an effective and safe treatment for chronic posterolateral instability of the elbow

BACKGROUND

Surgical treatment helps to restore stability of the elbow in patients with posterolateral rotatory instability (PLRI). The anconeus muscle is one of the most important active stabilizers against PLRI. A minimally invasive anconeus-sparing approach for lateral ulnar collateral ligament (LUCL) reconstruction using a triceps tendon autograft has been previously described. The purpose of this study was to evaluate the outcome of this intervention and identify risk factors that influenced the clinical and patient-reported outcomes.

METHODS

Sixty-one patients with chronic PLRI and no previous elbow surgery who underwent surgical reconstruction of the LUCL using a triceps tendon autograft in a minimally invasive anconeus-sparing approach during 2012 and 2018 were evaluated. Outcome measures included a clinical examination and the Oxford Elbow Score (OES) and the Mayo Elbow Performance Score (MEPS) questionnaires. Subjective patient outcomes were evaluated with the visual analog scale (VAS) for pain and the Subjective Elbow Value (SEV). Integrity of the common extensor tendons and centering of the radial head were assessed preoperatively on standardized magnetic resonance images (MRIs).

RESULTS

Fifty-two patients were available at final follow-up. The mean age of patients was 51 ± 12 years with a mean follow-up of 53 ± 14 months (range 20-76). Clinical examination after surgery (n = 41) showed no clinical signs of instability in 98% of the patients (P < .001) and a nonsignificant improvement in range of motion. OES, MEPS, and VAS scores averaged 40 ± 10 of 48 points, 92 ± 12 of 100 points, and 1 ± 2 points, respectively, all corresponding with good or excellent outcomes. The SEV was 88%, indicating very high satisfaction with the surgery. Only 1 patient had revision surgery due to pain, and there were no reported postoperative complications in this cohort. A radial head subluxation in the MRI correlated significantly with worse postoperative outcomes.

CONCLUSIONS

The anconeus-sparing minimally invasive technique for posterolateral stabilization of the elbow using a triceps tendon autograft is an effective and safe treatment for chronic posterolateral instability of the elbow with substantial improvements in elbow function and pain relief with a very low rate of persistent clinical instability.

The posterolateral ligament of the elbow: anatomy and clinical relevance

BACKGROUND

The posterolateral capsule was recognized in the past as an important structure for elbow stability but was later disregarded. Two recent biomechanical studies demonstrated its role in preventing posterolateral instability, and thus it should be identified as a distinct ligament: the posterolateral ligament (PLL). This study includes 2 parts: an anatomic study of the PLL's footprint and a collection of 5 cases of pathologic lesions of the PLL.

METHODS

Six cadaveric upper limbs were assessed. The attachments of the PLL were dissected, the footprints were marked and photographed, and the 2-dimensional area and length were measured.

RESULTS

The mean proximal attachment dimensions were a length of 13 mm and an area of 101 mm2, and the mean distal attachment dimensions were 19 mm and 111 mm2, respectively. There were 2 cases of posterolateral elbow pain in professional cricket bowlers, diagnosed radiographically as enthesopathy of the PLL's proximal attachment on the posterior capitellum, probably due to repeated forced hyperextension of the elbow. Both patients were treated by débridement of the posterior capitellum and reattachment of the PLL, with complete resolution of symptoms. In addition, there were 3 cases of clinical posterolateral rotatory instability in young patients. Two athletes had an isolated acute tear of the PLL, and on physical examination, both had positive posterior draw test results but negative pivot-shift test results. Both underwent elbow arthroscopy and repair of the PLL with resolution of symptoms. The third patient had long-standing recurrent elbow instability, following a failed lateral ulnar collateral ligament reconstruction, in the presence of an Osborne-Cotterill lesion. He underwent revision lateral ulnar collateral ligament reconstruction, bone grafting of the bony lesion, and reattachment of the PLL, with complete resolution of symptomatic posterolateral rotatory instability.

CONCLUSIONS

The PLL of the elbow has a significant role in the elbow's posterolateral stability. Its footprints were described, and its clinical significance was demonstrated in cases of elbow instability caused by acute ligament tears and elbow pain due to ligament enthesopathy. Surgeons should be aware of this structure and potential pathology related to its injury.

Arthroscopic assessment for lateral collateral ligament complex deficiency of the elbow: a cadaveric study

PURPOSE

To evaluate whether elbow instability due to lateral collateral ligament complex injury can be assessed reliably through arthroscopy.

METHODS

Eight fresh human cadaveric elbows were placed in a simulated lateral decubitus position. The radiocapitellar joint (RCJ) gap and ulnohumeral joint (UHJ) gap (mm) were measured with different sizes of probes from the posterolateral viewing portal. The elbow was 90 degrees flexed with neutral forearm rotation for RCJ gap measurement and 30 degrees flexed with full supination for UHJ gap measurement. Sequential testing was performed from Stage 0 to Stage 3 (Stage 0: intact; Stage 1: the release of the anterior 1/3 LCL complex; Stage 2: the release of the anterior two thirds of the LCL complex; and Stage 3: the release of the entire LCL complex) on each specimen. The mean gap of RCJ and lateral UHJ was used for the comparison between stages with the intact elbow.

RESULTS

The mean RCJ gap distance in Stage 2 and Stage 3 was significantly increased compared to that in Stage 0 (Stage 0 vs. Stage 2: P = .008; Stage 0 vs. Stage 3: P = .010). The mean UHJ gap distance of Stage 1, Stage 2, and Stage 3 was significantly increased compared to that in Stage 0 (Stage 0 vs. Stage 1: P = 0.025; Stage 0 vs. Stage 2: P = .010; Stage 0 vs. Stage 3: P = .011). In contrast, the release of the anterior 1/3 of the LCL complex (Stage 1) was not significantly increased compared to the mean joint gap distance of RCJ (P = .157).

CONCLUSION

Arthroscopic measurement of joint gap widening in RCJ and UHJ is a reliable assessment method to detect LCL complex deficiency that involves the anterior two thirds or more.

A Medial Approach That Provides Ample Exposure of the Coronoid for Fracture Management

We describe a medial approach to the coronoid where the flexor-pronator mass is released from its humeral origin by creating a proximally based tendinous flap. This technique facilitates access to the coronoid, preservation of the medial collateral ligament origin, and repair of the flexor-pronator mass. This approach has utility for all coronoid fracture variations but especially the O'Driscoll anteromedial subtype 3, which includes fractures of the sublime tubercle, the anteromedial facet, and the coronoid tip.

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.

Intraoperative arthroscopic classification tool for posterolateral elbow instability

Background

Introducing and implementing an arthroscopic classification tool for posterolateral elbow instability.

Methods

Thirty arthroscopies were performed on 30 patients, and all recordings were collected, blinded, and labeled. Three orthopedic surgeons reviewed and scored all 30 recordings three times with a period of at least seven days in between to analyze the intraobserver and interobserver reliability. The classification consisted of five different grades.

Results

Indications for elbow arthroscopy included impingement (n = 7), osteochondritis dissecans (n = 5), pain (n = 7), osteoarthritis (n = 6), and other (n = 5). The kappa value for intrarater reliability was 0.71, indicating good reliability, while the kappa value for inter-rater reliability was 0.38 indicating fair reliability.

Conclusion

This new classification is a tool for an arthroscopic assessment of PLRI and can be used as a standardized grading system for further research and communication between orthopedic surgeons. We demonstrated good intrarater reliability (k = 0.71) with fair inter-rater reliability (k = 0.38). However, further research is necessary to study the clinical significance.

Persistent elbow dislocation

Acute elbow dislocation is a common injury with an incidence in the general population estimated at around 5/100,000. Persistent (or static) elbow dislocation is a relatively rare problem but might occur due to inappropriate assessment or treatment of acute simple or complex elbow dislocations. Persistent elbow dislocation can be an invalidating and painful condition with a more ominous prognosis than an acute elbow dislocation with appropriate treatment. Surgical treatment of persistent elbow dislocation is a complex intervention that requires extended surgical exposure and arthrolysis in combination with circumferential ligamentous and osseous stabilization. Satisfactory results are described, but complication and reintervention rates are high. After-treatment with a dynamic external fixator is often necessary.

Posterolateral Rotatory Instability Develops Following the Modified Kocher Approach and Does Not Resolve Following Interval Repair

BACKGROUND

The modified Kocher and extensor digitorum communis (EDC)-splitting intervals are commonly utilized to approach the lateral elbow. Iatrogenic injury to the lateral ulnar collateral ligament may result in posterolateral rotatory instability (PLRI). in the present cadaveric study, we (1) evaluated lateral elbow stability following the use of these approaches and (2) assessed the accuracy of static lateral elbow radiographs as a diagnostic tool for PLRI.

METHODS

Ten matched-pair cadaveric upper-extremity specimens (n = 20) were randomly assigned to Kocher or EDC-splitting approaches. Specimens underwent evaluation pre-dissection, post-dissection, and following repair of the surgical interval. Clinical evaluation of lateral elbow stability was performed with the lateral pivot-shift maneuver. Radiographic radiocapitellar displacement was evaluated with the fully extended hanging arm test and on lateral elbow 30° flexion radiographs. Paired Wilcoxon signed-rank tests with Bonferroni correction were utilized to compare groups.

RESULTS

All Kocher group specimens (10 of 10) developed PLRI on the pivot-shift maneuver following dissection. No EDC-splitting group specimens (0 of 10) developed instability with pivot-shift testing. The fully extended hanging arm test showed no difference in radiocapitellar displacement between groups (p > 0.008). Lateral elbow 30° flexion radiographs in the Kocher group showed an increased radiocapitellar displacement difference (mean, 8.46 mm) following dissection compared with the pre-dissection baseline (p < 0.008). Following repair of the Kocher interval, the radiocapitellar displacement (mean, 6.43 mm) remained greater than pre-dissection (mean, 2.26 mm; p < 0.008). In the EDC-splitting group, no differences were detected in radiocapitellar displacement on lateral elbow radiographs with either the fully extended hanging arm or lateral elbow 30° flexion positions.

CONCLUSIONS

The Kocher approach produced PLRI that did not return to baseline conditions following repair of the surgical interval. The EDC-splitting approach did not cause elbow instability clinically or radiographically. The hanging arm test was not reliable for the detection of PLRI.

CLINICAL RELEVANCE

The Kocher interval for lateral elbow exposure results in iatrogenic PLRI that is not detectable on the hanging arm test and that does not return to baseline stability following repair of the surgical interval.

Conservative versus surgical management of isolated O'Driscoll II coronoid fracture: A systematic review

PURPOSE

The purpose of this systematic review is to summarize the current literature on conservative and surgical management of isolated O'Driscoll II coronoid fracture.

STUDY DESIGN

Systematic review.

METHODS

We systematically searched Medline, Embase, Google Scholar, and Web of Science databases for published studies by complying with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and using the keywords "isolated coronoid fracture," "O'Driscoll type 2 coronoid fracture," "anteromedial coronoid fracture," "anteromedial facet coronoid fracture," "posteromedial rotatory instability," and "varus posteromedial rotatory instability." Patients were divided into conservative treatment and surgical treatment groups. Oxford Centre for Evidence-Based Medicine and Methodological Index for Non-Randomized Studies were assessed to determine each article's quality. The primary outcomes of the present reviews were the Mayo elbow performance score (MEPS) and the disabilities of the arm, shoulder, and hand (DASH) score, and the secondary outcomes were associated with complications and reoperations. Eligible trials were independently chosen by two review authors, and a third reviewer resolved all disagreements.

RESULTS

The search yielded 458 records, among which 446 articles were of relevance, and 12 were included. In the final review, 138 patients were evaluated-98 (71%) who received surgical treatment and 40 (29%) who received conservative treatment. The mean MEPS score and the DASH score of surgical treatment were 91 and 8, respectively; 69.8% of patients had excellent scores, and 27.0% had good scores. The mean MEPS score and the DASH score of conservative treatment were 92 and 12, respectively; 70.6% of patients had excellent scores, and 23.5% had good scores.

CONCLUSIONS

In select cases, conservative treatment can achieve good results in the treatment of isolated O'Driscoll II coronoid fracture when a stricter indication is followed. However, there is insufficient evidence to recommend the appropriate treatment for a particular fracture subtype, and there is a need for more high-quality randomized controlled trials to determine which treatment is superior.

Arthroscopic Techniques to Recognize and Quantify Subtle Medial and Lateral Elbow Instability

The diagnosis and treatment of elbow instability can be challenging for surgeons. Although history, physical examination, radiographs, and advanced imaging such as stress ultrasound scanning and magnetic resonance imaging are helpful, diagnostic arthroscopy is a valuable tool in the armamentarium of an elbow surgeon. Elbow arthroscopy is not only a diagnostic tool but also has the added therapeutic benefits that are not available with other diagnostic modalities. The purpose of this article and associated video is to present 3 arthroscopic techniques to help elbow surgeons arthroscopically recognize and quantify medial and lateral elbow instability.

The lateral ulnar collateral ligament: Anatomical and structural study for clinical application in the diagnosis and treatment of elbow lateral ligament injuries

The lateral ulnar collateral ligament (LUCL) is considered one of the main stabilizers of the elbow. However, its anatomical description is not well established. Imaging techniques do not always have agreed upon parameters for the study of this ligament. Therefore, herein, we studied the macro and microanatomy of the LUCL to establish its morphological and morphometric characteristics more precisely. Fifty-five fresh-frozen human elbows underwent dissection of the lateral collateral ligament. Morphological characteristics were studied in detail. Ultrasound (US) and magnetic resonance (MR) were done before dissection. Two specimens were selected for PGP 9.5 S immunohistochemistry. Ten additional elbows were analyzed by E12 sheet plastination. LUCL was identified in all specimens and clearly defined by E12 semi-thin sections. It fused with the common extensor tendon and the radial ligament. The total length of the LUCL was 48.50 mm at 90°, 46.76 mm at maximum flexion and 44.10 mm at complete extension. Three morphological insertion variants were identified. Both US and MR identified the LUCL in all cases. It was hypoechoic in the middle and distal third in 85%. The LUCL was hypointense on MR in 95%. Free nerve endings were present on histology. The LUCL is closely related to the anular ligament. It is stretched during flexion and supination. US and MR can reliably identify its fibers. Anatomical data are relevant to the surgeon who repairs the ligaments of the elbow. Also, to the radiologist and pain physician who interpret imaging and treat patients with pain syndromes of the elbow.

[Monteggia-like injuries : Pitfalls of surgical treatment]

The term Monteggia-like lesions or Monteggia equivalent injuries includes fractures of the proximal ulna with dislocation and dislocation fractures of the radial head from the proximal radio-ulnar joint. The complexity of the injury requires a dedicated understanding of the anatomical structures and their biomechanical properties. Particularly due to the rarity, the complication and revision rates are high. A conservative treatment is not usually effective. Three-dimensional imaging by computed tomography is part of the surgical preparation. The goal of surgical treatment is osteosynthetic reconstruction of the fractures and restoration of joint congruency. In cases of nonreconstructable radial head fractures, radial head arthroplasty may be necessary. In addition to reconstruction of the bony stabilizers, refixation of the ligamentous structures is essential for treatment success. The combination of complex fracture patterns and possible dislocation positions in the ulnohumeral, radiohumeral and proximal radio-ulnar joints poses a great challenge to the surgeon. The most frequent complications are peri-implant infections, implant failure, loss of reduction, stiffness or instability. Especially the anatomical configuration of the proximal ulna is complex and requires accurate reconstruction. Therefore, reconstruction of the proximal ulna in length and rotation, including the coronoid process, is considered to be a key factor in the surgical treatment of Monteggia-like injuries.

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

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

Biomechanical impact of elbow motion in elbow stiffness

BACKGROUND

A mechanical block in the elbow due to osteophytes in the olecranon fossa is a common clinical symptom for elbow stiffness.

PURPOSE/HYPOTHESIS

This study aims to understand the biomechanical characteristics or changes in the stiff elbow in the resting (or neutral) and swing position of the arm using a cadaveric model. The hypotheses included the following: (1) a difference exists in the articular contact pressure of the elbow by comparing the non-stiff and stiff models in in vivo studies; (2) the degree of stiffness would affect the increase of the joint loading of the elbow.

STUDY DESIGN

Controlled laboratory study, cadaveric study.

METHODS

Eight fresh-frozen specimens from individuals of both sexes were included in the biomechanical study. The specimen was mounted on a custom-designed jig system with gravity-assisted muscle contracture to mimic the elbow in a standing position. The elbow was tested in two conditions (the resting and passive swing). Contact pressure was recorded for three seconds in the resting position, which was the neutral position of the humerus. By dropping the forearm from 90° of the elbow flexion, the passive swing was performed. The specimens were tested sequentially in three stages of stiffness (stage 0, no stiffness; stage 1, 30° of extension limitation; and stage 2, 60° of extension limitation). After data collection was completed in stage 0, a stiff model was sequentially created for each stage. The stiff model of the elbow was created by blocking the olecranon by inserting a 2.0 K-wire into the olecranon fossa horizontally with the intercondylar axis.

RESULTS

The mean contact pressures were 279 ± 23, 302 ± 6, and 349 ± 23 kPa in stages 0, 1, and 2, respectively. The increases in the mean contact pressure in stages 2 versus 0 were significant (P < 0.0001). The mean contact pressures were 297 ± 19, 310 ± 14, and 326 ± 13 kPa in stages 0, 1, and 2, respectively. The peak contact pressures were 420 ± 54, 448 ± 84, and 500 ± 67 kPa in stages 0, 1, and 2, respectively. The increases in mean contact pressure in stage 2 versus 0 were significant (P = 0.039). The increases in peak contact pressure in stages 0 versus 2 were significant (P = 0.007).

CONCLUSIONS

The elbow bears the load created by gravity and muscle contracture in the resting and swing motion. Moreover, extension limitation of stiff elbow increases the load bearing in the resting position and swing motion. Careful surgical management should be considered for meticulous clearance of bony spur around olecranon fossa to resolve the extension limitation of the elbow.

Ultrasound assessment of the posterolateral elbow ulnohumeral gap in normal subjects with and without posterolateral drawer testing

Background

Posterolateral rotator instability (PLRI) is the most common pattern of recurrent elbow instability, and current imaging to aid PLRI diagnosis is limited. Thus, we sought to define use of ultrasound (US) to determine normal lateral ulnohumeral joint measurements, with and without posterolateral drawer testing to provide an insight into how US may aid diagnosis.

Methods

Sixty elbows were evaluated in thirty healthy volunteers. The lateral ulnohumeral gap (LUHG) was measured with US in the resting position while the posterolateral drawer stress test maneuver was applied. Joint laxity was calculated as the difference between maximum stress and average rest measurements. Two independent readers assessed each elbow with comparison performed between stress and rest positions.

Results

Differences in the LUHG were evident between stress and rest conditions (reader 1: P < .0001 and reader 2: P = .0002). At rest, median LUHG values were 2.31 mm and 2.05 mm for readers 1 and 2 respectively, while at stress 2.88 mm and 2.9 mm for readers 1 and 2. Median joint laxity was 0.8 mm for reader 1 and 1.1 mm for reader 2. Pearson correlation was r = 0.457 (absolute intraclass correlation coefficient [ICC] = 0.608) while under stress and r = 0.308 (absolute intraclass correlation coefficient [ICC] = 0.417) at rest. Median joint laxity demonstrated a Pearson correlation of r = 0.161 and absolute intraclass correlation coefficient [ICC] = 0.252.

Conclusions

This study demonstrates a dynamic US assessment for PLRI, which aimed to assess the usefulness and feasibility of a laxity measurement after the application of a posterolateral drawer stress maneuver in a healthy population. Although establishing concordance between readers in measuring an LUHG under stress, the utility of a laxity measurement alone is not clear as correlation of measurements is not excellent; hence, an upper limit of normal for the ulnohumeral gap under stress may be more useful. Further evaluation of this technique is required in patients with PLRI.

Lateral elbow ligament reconstruction for posterolateral rotatory instability: 10 years follow-up in 32 patients

Background

Posterolateral rotatory instability (PLRI) is the most frequent form of both acute and chronic elbow instability. It is due to mechanical incompetence of the lateral collateral ligament. O'Driscoll et al described treatment of this instability by autologous reconstruction of the lateral ulnar collateral ligament. The aim of our study was to evaluate the medium and long-term clinical, functional and radiological results of patients who were surgically treated for PLRI by this technique. We hypothesized that such ligament reconstruction restores a functional joint complex and durably stabilizes the elbow and limits the long-term risk of osteoarthritis.

Methods

All patients treated for symptomatic PLRI by ligament reconstruction since January 1995 and who had a minimum follow-up of 36 months were retrospectively included.

Results

Thirty-two patients (32 elbows) underwent clinical and radiological evaluation with a mean follow-up of 112 months (range, 36-265 months). The success rate of the procedure was 97% with one patient requiring revision reconstruction. Twenty-four patients (75%) were free from pain. Pain was significantly greater in patients with associated lesions (P = .03) and those with morbid obesity (body mass index ≥40) (P = .03). Twenty-nine (91%) patients had resumed their previous activities. Twenty-eight patients (87%) were satisfied or very satisfied. The mean Mayo Clinic score was 96/100 and the QuickDash 14.7/100. Two patients (6%) with accompanying lesions developed severe osteoarthritis.

Conclusion

Elbow ligament reconstruction by the technique of O'Driscoll et al effectively restores stability and limits progression to osteoarthritis in the long term. The only failure in our series was due to several technical errors. Patients who had dislocation with associated lesions or morbid obesity are at risk of poorer functional results.

The role of the lateral part of the distal triceps and the anconeus in varus stability of the elbow: a biomechanical study

BACKGROUND

The role of the lateral part of the distal triceps as a stabilizer in the lateral collateral ligament-deficient elbow and whether its effect in improving the stability is independent of that of the anconeus are unclear.

METHODS

Seven cadaveric elbows were tested under gravity varus stress using a custom-made machine designed to simulate muscle loads while allowing passive flexion of the elbow. An injury model was created by sectioning the lateral collateral ligament and sparing the common extensor origin. The lateral part of the distal triceps tendon was loaded sequentially with 0 N, 10 N, 25 N, and 40 N. Each stage of the lateral part of the distal triceps loading was tested with the anconeus unloaded (inactive) or with a 25-N load applied (active). Articular contact pressures on the coronoid, the medial facet, and the lateral facet were collected and processed using Tekscan sensors and software.

RESULTS

A significant decrease in the mean coronoid contact pressure was seen with sequential loading of the lateral part of the distal triceps (P < .001). The ratio of medial to lateral facet contact pressures significantly decreased with sequential loading of the lateral part of the distal triceps (P < .001), indicating a better distribution of the contact pressure between the medial and lateral facets as the lateral part of the distal triceps was loaded. These effects were statistically significant, both with and without anconeus loading. There was no significant modification of the effect of the lateral part of the distal triceps loading on the contact pressure by the anconeus loading (P = .47). However, with active anconeus loading, the contact pressure and the ratio of medial to lateral facet contact pressures were significantly lower for any stage of lateral triceps loading (P < .001), indicating a synergistic effect of the anconeus.

CONCLUSIONS

In a lateral collateral ligament-deficient elbow, the lateral part of the distal triceps loading prevents the increased contact pressure on the coronoid under varus stress and improves the distribution of contact pressures on the coronoid. Anconeus loading further decreases and improves the distribution of the contact pressures; however, its effect is independent of that of the lateral part of the distal triceps. These results substantiate a role of the lateral part of the distal triceps as a dynamic constraint against elbow varus and have clinical implications for prevention and rehabilitation of elbow instability.

The role of the lateral collateral ligament-capsule complex of the elbow under gravity varus

BACKGROUND

The lateral collateral ligament complex along with the capsule is likely to be at risk during arthroscopic extensor carpi radialis brevis release for lateral epicondylitis. We hypothesized that disruption of the lateral collateral ligament-capsule complex (LCL-cc) would increase the mean contact pressure on the coronoid under gravity varus.

MATERIALS AND METHODS

Eight cadaveric elbows were tested via gravity varus and weighted varus (2 Nm) stress tests using a custom-made machine designed to simulate muscle loads while allowing passive flexion of the elbow. Mean articular surface contact pressure data were collected and processed using intra-articular thin-film sensors and software. Sequential testing was performed on each specimen from stage 0 to stage 3 (stage 0, intact; stage 1, release of anterior one-third of LCL-cc; stage 2; release of anterior two-thirds of LCL-cc; and stage 3, release of entire LCL-cc). The mean contact pressure on the coronoid and the mean ratio of contact pressure on the medial coronoid to that on the lateral coronoid (M/L ratio) were used for comparisons among the stages and the intact elbow.

RESULTS

The overall mean contact pressure significantly increased in stage 2 (P = .0004 in gravity varus and P = .0001 in weighted varus) and stage 3 (P < .0001 in gravity varus and P < .0001 in weighted varus) compared with that in stage 0. In contrast, release of the anterior one-third of the LCL-cc (stage 1) did not significantly increase the mean contact pressure on the coronoid in any degree of flexion under gravity varus (P = .09) or weighted varus loading (P = .6). The M/L ratio difference between stage 0 and stage 1 was 1.1 ± 1.1 under gravity varus (P = .8) and 2.1 ± 1.0 under weighted varus (P = .2). The overall M/L ratios in stage 2 and stage 3 were significantly higher than those seen in stage 0 under gravity varus (P = .04 in stage 2 and P = .02 in stage 3) and weighted varus (P = .006 in stage 2 and P < .0001 in stage 3).

CONCLUSIONS

Loss of the anterior two-thirds or more of the LCL-cc significantly increases the overall mean contact pressure on the coronoid, especially the medial coronoid, under both gravity varus and weighted varus. The LCL-cc also plays a role in the distribution of coronoid contact pressure against gravity varus loads.

Prospective clinical results of an additive ligament bracing for stabilizing simple and complex elbow instabilities

INTRODUCTION

Ligament bracing augments ligament repair using a non-absorbable suture tape. Although biomechanically an increase in primary stability has been proven, there is a lack of clinical evidence. Purpose of this study was to evaluate clinical results of patients treated with ligament bracing due to primary elbow instability, including an analysis of complications. Furthermore, clinical results for patients treated with and without early functional mobilization were compared.

MATERIALS AND METHODS

This prospective case-series evaluated clinical and functional results from patients treated with ligament bracing due to primary elbow instability. Clinical outcome measures were range of motion (ROM) as well as objective and subjective elbow scores [Mayo Elbow Performance Score (MEPS); Disabilities of Arm, Shoulder and Hand Score (DASH score)]. Stability was evaluated sonographically by humero-radial gapping under varus stress.

RESULTS

This study involved 34 patients treated with ligament bracing. After a mean follow-up of 12.9 months ROM was 112° ± 29, MEPS 88 ± 13 points, DASH 91 ± 11 points, and 84% were satisfied with their result. Lateral joint gapping was 2.4 mm. No significant difference was observed regarding a postoperative mobilization with and without limitations. Most common complication after ligament bracing was elbow stiffness including heterotopic ossifications in four patients (12%).

CONCLUSION

Operatively treated elbow instability with additional ligament bracing results in good clinical outcomes with high patient satisfaction and recovery of elbow stability. The high primary stability of the ligament bracing allows early functional mobilization without bracing, which facilitates postoperative rehabilitation. Elbow stiffness with heterotopic ossification seems to be a potential complication. Furthermore, the optimal tensioning of the ligament bracing remains challenging, including the risk of an over tensioning.

LEVEL OF EVIDENCE

III.

[Winter sports injuries to the elbow joint]

BACKGROUND

Elbow injuries occur quite often when practicing winter sports. Due to the high sports dynamics and risk of fall the elbow joint is prone to injuries. Hereby, the most common injury is the dislocation of the elbow.

TREATMENT

Isolated ligamentous instabilities can usually be treated non-operatively when the joint is centered on post-reduction imaging. In the case of persistent symptomatic instability, secondary ligament reconstruction surgery is associated with reliable and good results. Most fractures of the elbow involve the radial head in terms of postero-lateral rotation instability, whereas distal humerus and olecranon fractures are more likely to occur in high-energy or direct trauma. Indication for surgical treatment is given according to common guidelines, including involvement of the joint line, fragment dislocation and instability with risk of secondary fracture dislocation. Minimally invasive techniques for the radial head as well as anatomic preformed locking plate systems seem to have reached a wide acceptance.

Modified Graft Loop Technique Augmented With Nonabsorbable Suture Tape for Chronic Elbow Dislocation

The task of achieving a good clinical outcome on patients with chronic elbow dislocation is arduous. Any stabilization method used should be robust enough in order to allow for early elbow motion. Immobilization of the elbow for a prolonged time period may lead to stiffness and heterotopic ossification. Several methods of ligament reconstruction have tried to address the global instability that is present in such scenarios. We describe a technique of reconstructing both bands of the medial ligament, and the lateral ulnar collateral ligament of the elbow, by using a looped tendon graft and reinforcing the lateral side with nonabsorbable tape and anchors. The graft is passed as a loop once through the humerus and ulna, recreating the anterior portion of the medial collateral ligament and the lateral ulnar collateral ligament. Then the lateral side is augmented with the tape and anchors and the loop is fixed. Lastly, the medial tail of the graft is used in order to recreate the posterior part of the medial ligament. This technique uses a single graft along with nonabsorbable tape and anchors to make a robust construct that will withstand early range of motion, without jeopardizing elbow stability. Potential complications include damage to the ulnar nerve, infection, elbow stiffness, or persistent instability in complex cases with bone involvement.

Classification of coronoid process fractures: A pending question

Ulna coronoid fracture is a complicated elbow injury. Comprehensive classification of coronoid fracture can assist diagnosis, guide treatment, and improve prognosis. Existing coronoid fracture classifications are insufficient to interpret all fracture patterns. The coronoid fracture classification is associated with elbow-specific trauma patterns. Coronoid fractures are often associated with other elbow injuries, commonly with radial head fractures, which makes the clinical strategies inconsistent and prognosis poor. The current fracture classifications do not contain information about combined injuries. Preservation of ulnohumeral joint contact after trauma is critical to elbow mechanical and kinematic stability. Important fracture types for treatment include terrible-triad injuries and anteromedial facet fractures. Open reduction and internal fixation of these two fractures should be conducted when marked displacement of the fragment, elbow instability under stress, and complicated associated injuries. The current surgical tactics based on classifications are still controversial.

Greater sigmoid notch dysplasia causing elbow instability: Lateral ligament reconstruction and Stamp osteotomy

The coronoid is one of the elbow's primary static stabilisers, and the importance of reconstruction following fracture with instability has been established. In the developing elbow, instability can lead to greater sigmoid notch dysplasia that can make reconstruction challenging. A novel technique to improve osseous stability with an opening wedge 'stamp osteotomy' reconstruction of the coronoid is described combined with a lateral ligament reconstruction, in two patients with recurrent posteromedial rotatory instability. The technique improves congruity and coverage of the greater sigmoid notch with the trochlea whilst maintaining articular cartilage. Extra-articular iliac crest bone graft is used to maintain the position with buttress plate support. The surgical technique is described and the clinical and radiographic outcome reported in two patients. Level of evidence: IV.

The effect of axillary crutch length on upper limb kinematics during swing-through gait

BACKGROUND

Axillary crutches are commonly used in rehabilitation. Inappropriately fit crutches may result in upper limb pain or injury.

OBJECTIVE

To investigate the effects of axillary crutch length on upper limb kinematics to better understand potential injury mechanisms. It was hypothesized that crutches that were longer or shorter than standard-fit crutches would alter upper limb kinematics.

DESIGN

Cross-sectional.

SETTING

Gait laboratory.

PARTICIPANTS

Fifteen healthy males with no prior crutch experience.

INTERVENTIONS

Participants were fit with axillary crutches using standardized methods, as well as with crutches that were 5 cm longer and 5 cm shorter. Participants performed swing-through gait (1.20 ± 0.07 ms^-1 ) with all crutch lengths in randomized order. Kinematics were recorded using an optical motion-tracking system and joint angles for the scapula, shoulder, elbow, and wrist were computed.

MAIN OUTCOME MEASURES

The effects of crutch length on joint range of motion (ROM) and joint angles at initial crutch contact were analyzed using multivariate analysis (Hotelling's T² ; α = .025) and simultaneous confidence intervals (CI).

RESULTS

The long-standard crutch fit comparison showed effects across all joints (ROM p = .009; initial contact p < .001). Longer crutches resulted in greater scapular upward rotation (mean difference [95% CI] ROM: 1.0 [-0.2 to 2.2]; initial contact: -2.7 [-4.4, -1.1]) and shoulder abduction (ROM: 0.8 [-0.1 to 1.8]; initial contact: -1.9 [-4.1 to 0.3]). Crutch length also had effects across all joints for the short-standard fit comparison (ROM p = .004; initial contact p = .016). Shorter crutches resulted in greater scapula downward rotation (2.2 [-0.4 to 4.8]) and greater shoulder adduction (2.5 [-0.6 to 5.6]) at initial contact. Shorter crutches also reduced shoulder flexion/extension ROM (-2.5 [-4.4 to -0.6]).

CONCLUSIONS

Altered crutch length results in scapular and shoulder kinematic deviations that may present risk factors for upper limb injury with crutch-walking. This may underline the importance of appropriate device fitting to reduce injury risk in crutch users.

TREATMENT OF SIMPLE CHRONIC INSTABILITY OF THE ELBOW JOINT

Simple chronic instability of the elbow joint is one of the urgent problems in modern traumatology due to the fact that the standard tactics of managing patients with traumatic injuries of the elbow joint due to dislocation, which amounts to its elimination, immobilization of the upper limb and subsequent development of movements in the joint, most often does not take into account damage to specific soft tissue structures. With untimely treatment for qualified help, with late or unsuccessful attempts to eliminate dislocation of the bones of the forearm, less often with chronic traumatization of the ligamentous apparatus of the elbow joint during some types of occupation, one of the most unpleasant complications may form, namely, chronic instability. This article discusses the main types of chronic instability of the elbow joint, analyzes approaches to the management of patients with simple chronic instability. Despite the not very high occurrence of this pathology, the effectiveness of modern surgical treatment options aimed at reconstruction of the ligamentous apparatus of the elbow joint, the percentage of unsatisfactory results of treatment of simple chronic recurrent and persistent instability of the elbow joint remains high.

LUCL reconstruction of the elbow: clinical midterm results based on the underlying pathogenesis

PURPOSE

Traumatic and atraumatic insufficiency of the lateral ulnar collateral ligament (LUCL) can cause posterolateral rotatory instability (PLRI) of the elbow. The influence of the underlying pathogenesis on functional outcomes remains unknown so far. The objective of this study was to determine the impact of the initial pathogenesis of PLRI on clinical outcomes after LUCL reconstruction using an ipsilateral triceps tendon autograft.

METHODS

Thirty-six patients were reviewed in this retrospective study. Depending on the pathogenesis patients were assigned to either group EPI (atraumatic, secondary LUCL insufficiency due to chronic epicondylopathia) or group TRAUMA (traumatic LUCL lesion). Range-of-motion (ROM) and posterolateral joint stability were evaluated preoperatively and at follow-up survey. For clinical assessment, the Mayo elbow performance (MEPS) score was used. Patient-reported outcomes (PROs) consisting of visual analogue scale (VAS) for pain, disability of arm, shoulder and hand (DASH) score, patient-rated elbow evaluation (PREE) score and subjective elbow evaluation (SEV) as well as complications were analyzed.

RESULTS

Thirty-one patients (group EPI, n = 17; group TRAUMA, n = 14), 13 men and 18 women with a mean age of 42.9 ± 11.0 were available for follow-up evaluation (57.7 ± 17.5 months). In 93.5%, posterolateral elbow stability was restored (n = 2 with re-instability, both group TRAUMA). No differences were seen between groups in relation to ROM. Even though group EPI (98.9 ± 3.7 points) showed better results than group TRAUMA (91.1 ± 12.6 points) (p = 0.034) according to MEPS, no differences were found for evaluated PROs (group A: VAS 1 ± 1.8, PREE 9.3 ± 15.7, DASH 7.7 ± 11.9, SEV 92.9 ± 8.3 vs. group B: VAS 1.9 ± 3.2, PREE 22.4 ± 26.1, DASH 16.0 ± 19.4, SEV 87.9 ± 15.4. 12.9% of patients required revision surgery.

CONCLUSION

LUCL reconstruction using a triceps tendon autograft for the treatment of PLRI provides good to excellent clinical outcomes regardless of the underlying pathogenesis (traumatic vs. atraumatic). However, in the present case series, posterolateral re-instability tends to be higher for traumatic PLRI and patient-reported outcomes showed inferior results.

LEVEL OF EVIDENCE

Therapeutic study, LEVEL III.

Ultrasonographic Measurement of Elbow Varus Laxity With a Sequential Injury Model of the Lateral Collateral Ligament-Capsular Complex

Background

There is no consensus how to determine the varus laxity due to the LCL injury using the ultrasonography. There is a risk of lateral collateral ligament injury during or after arthroscopic extensor carpi radialis brevis release for tennis elbow. The equator of the radial head has been suggested as a landmark for the safe zone to not increase this risk; however, the safe zone from the intra-articular space has not been established.

Hypothesis

Increased elbow varus laxity due to lateral collateral ligament-capsular complex (LCL-cc) injury could be assessed reliably via ultrasound.

Study Design

Descriptive laboratory study.

Methods

Eight cadaveric elbows were evaluated using a custom-made machine allowing passive elbow flexion under gravity varus stress. The radiocapitellar joint (RCJ) space was measured via ultrasound at 30° and 90° of flexion during 4 stages: intact elbow (stage 0), release of the anterior one-third of the LCL-cc (stage 1), release of the anterior two-thirds (stage 2), and release of the entire LCL-cc (stage 3). Two observers conducted the measurements separately, and the mean RCJ space in the 3 LCL-cc injury models (stages 1-3) at both flexion angles was compared with that of the intact elbow (stage 0). We also compared the measurements at 30° versus 90° of flexion.

Results

At 30° of elbow flexion, the RCJ space increased 2 mm between stages 0 and 2 (95% confidence interval [CI], 1-3 mm; P < .01) and 4 mm between stages 0 and 3 (95% CI, 2-5 mm; P < .01). At 90° of elbow flexion, the RCJ space increased 1 mm between stages 0 and 2 (95% CI, 1-2 mm; P < .01) and 2 mm between stages 0 and 3 (95% CI, 2-3 mm; P < .01).

Conclusion

Elbow varus laxity under gravity stress can be reliably assessed via ultrasound by measuring the RCJ space.

Clinical Relevance

Because ultrasonographic measurement of the RCJ space can distinguish the increasing varus laxity seen with release of two-thirds or more of the LCL-cc, the anterior one-third of the LCL-cc, based on the diameter of the radial head, can be considered the safe zone in arthroscopic extensor carpi radialis brevis release for tennis elbow.

Elbow Instability

The stability of the elbow is based on a combination of primary (static) and secondary stabilizers (dynamic). In varus stress, the bony structures and the lateral ulnar collateral ligament (LUCL) are the primary stabilizers, and in valgus stress, the ulnar collateral ligament (UCL) is the primary stabilizer. The flexor and extensor tendons crossing the elbow joint act as secondary stabilizers. Elbow instability is commonly divided into acute traumatic and chronic instability. Instability of the elbow is a continuum, with complete dislocation as its most severe form.Posterolateral rotatory instability is the most common elbow instability and can be detected at imaging both in the acute as well as the chronic phase. Imaging of suspected elbow instability starts with radiographs. Depending on the type of injury suspected, it is followed by magnetic resonance imaging (MRI) or computed tomography evaluation for depiction of a range of soft tissue and osseous injures. The most common soft tissue injuries are tears of the LUCL and the radial collateral ligament; the most common osseous injuries are an osseous LUCL avulsion, a fracture of the coronoid process, and a radial head fracture.Valgus instability is the second most common instability and mostly detected in the chronic phase, with valgus extension overload the dominant pattern of injury. The anterior part of the UCL is insufficient in valgus extension overload due to repetitive medial tension seen in many overhead throwing sports, with UCL damage readily seen at MRI.

Acute Ligament Injuries of the Elbow

Ulnar collateral, radial collateral, lateral ulnar collateral, and annular ligaments can be injured in an acute trauma, such as valgus stress in athletes and elbow dislocation. Recognizing normal anatomy in magnetic resonance imaging and ultrasonography studies is important to identify ligamentous abnormalities in these imaging modalities.

Overuse-related instability of the elbow: the role of CT-arthrography

The elbow is a complex joint whose biomechanical function is granted by the interplay and synergy of various anatomical structures. Articular stability is achieved by both static and dynamic constraints, which consist of osseous as well as soft-tissue components. Injuries determining instability frequently involve several of these structures. Therefore, accurate knowledge of regional anatomy and imaging findings is fundamental for a precise diagnosis and an appropriate clinical management of elbow instability. This review focuses particularly on the varied appearance of overuse-related elbow injuries at CT-arthrography.

The role of the brachialis muscle in elbow stability with collateral ligament injury: A biomechanical investigation

BACKGROUND

The brachialis muscle lies in close anatomic relation to the anterior capsule of the elbow joint. The contribution of the brachialis muscle to elbow stability has not yet been fully investigated. Therefore, the aim of this biomechanical in-vitro study was to analyze its influence on joint stability.

METHODS

Nine fresh frozen cadaveric elbows were evaluated for stability against valgus and varus/posterolateral rotatory forces. Brachialis loading was measured indirectly using strain gauges. Three distinct scenarios were analyzed: A) with intact lateral ulnar and ulnar collateral ligaments B) with a ruptured lateral ulnar collateral ligament C) with ruptured lateral ulnar and ulnar collateral ligaments.

FINDINGS

In all scenarios, an increased strain was observed under posterolateral rotatory/varus forces. The maximum measured strain occurred with elbow flexion of 30° and pronation of the forearm. The strain was significantly higher with dual-ligament rupture (mean - 210.5 μm/m; min. 97.8 μm/m; max. -310 μm/m; SD 107.8 μm/m; p = .034) compared to intact ligaments (mean - 106.9 μm/m; min. -32.51 μm/m, max. -287 μm/m; SD 100.2 μm/m) and single-ligament rupture (mean - 109.5 μm/m; min. - 96.7 μm/m; max - 130.4 μm/m; SD 18.2).

INTERPRETATION

A strain of the brachialis muscle was observed under varus/posterolateral rotatory forces with a pronated forearm and the strain increased significantly in the event of a dual-ligament rupture. This suggests that the brachialis muscle may influence varus/posterolateral rotatory stability of the elbow. Hence, a concomitant tear of the brachialis muscle might result in pronounced instability following simple elbow dislocation.

LEVEL OF EVIDENCE

Basic Science Study, Biomechanics.

Autologous triceps tendon graft for LUCL reconstruction of the elbow: clinical outcome after 7.5 years

PURPOSE

The objective of this study was to assess mid- to long-term functional outcomes in patients treated for symptomatic posterolateral instability of the elbow (PLRI) using an autologous ipsilateral triceps tendon as graft.

METHODS

A total of 196 patients were treated with autologous triceps tendon graft for symptomatic PLRI at single orthopedic institution from 2006 to 2013. The surgical treatment contained arthroscopic instability testing, reconstruction of the lateral ulnar collateral ligament (LUCL) and harvesting autologous ipsilateral triceps tendon as graft. The follow-up outcomes included range of motion (ROM), pain measured on a visual analogue scale (VAS), Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES) and ultrasound to evaluate the integrity of the refixation of the common extensor.

RESULTS

A total of 178 patients (female: 73; male: 105) were available for follow-up at a mean of 91 months (range 48-144). No patient reported pain at rest; VAS during activity was 1.8 (range 0-5). The ROM decreased slightly compared to preoperative measurements. Flexion decreased significantly from 135.4 to 131.1, though still within the functional arc of motion. All but 13 patients (8.5%) were clinically stable. However, only two patients received a revision of the LUCL reconstruction due to subjective instability. The mean MEPS in the final follow-up was 91.3 (range 73-100). The mean OES was 46.5 (range 39-48). Three patients reported a pain-free clicking of the elbow. No patient complained about donor site morbidity of the ipsilateral triceps tendon. Ultrasound evaluation showed integrity of the common extensors in all patients.

CONCLUSIONS

LUCL reconstruction using the ipsilateral triceps tendon as graft shows good to excellent mid- to long-term results in the treatment of symptomatic posterolateral elbow joint instability with a low re-instability and complication rate.

Novel Radiographic Indexes for Elbow Stability Assessment: Part A-Cadaveric Validation

INTRODUCTION

Elbow bony stability relies primarily on the high anatomic congruency between the humeral trochlea and the ulnar greater sigmoid notch. No practical tools are available to distinguish different morphotypes of the proximal ulna and herewith predict elbow stability. The aim of this study was to assess inter-observer reproducibility, evaluate diagnostic performance and determine responsiveness to change after simulated coronoid process fracture for three novel elbow radiographic indexes.

METHODS

Ten fresh-frozen cadaver specimens of upper limbs from human donors were available for this study. Three primary indexes were defined, as well as two derived angles: Trochlear Depth Index (TDI); Posterior Coverage Index (PCI); Anterior Coverage Index (ACI); radiographic coverage angle (RCA); olecranon-diaphisary angle (ODA). Each index was first measured on standardized lateral radiographs and subsequently by direct measurement after open dissection. Finally, a type II coronoid fracture (Regan and Morrey classification) was created on each specimen and both radiographic and open measurements were repeated. All measurements were conducted by two orthopaedic surgeons and two dedicated musculoskeletal radiologists.

RESULTS

All three indexes showed good or moderate inter-observer reliability and moderate accuracy and precision when compared to the gold standard (open measurement). A significant change between the radiographic TDI and ACI before and after simulated coronoid fracture was observed [TDI: decrease from 0.45 ± 0.03 to 0.39 ± 0.08 (p = 0.035); ACI: decrease from 1.90 ± 0.17 to 1.58 ± 0.21 (p = 0.001)]. As expected, no significant changes were documented for the PCI. Based on these data, a predictive model was generated, able to identify coronoid fractures with a sensitivity of 80% and a specificity of 100%.

CONCLUSION

New, simple and easily reproducible radiological indexes to describe the congruency of the greater sigmoid notch have been proposed. TDI and ACI change significantly after a simulated coronoid fracture, indicating a good responsiveness of these parameters to a pathological condition. Furthermore, combining TDI and ACI in a regression model equation allowed to identify simulated fractures with high sensitivity and specificity. The newly proposed indexes are, therefore, promising tools to improve diagnostic accuracy of coronoid fractures and show potential to enhance perioperative diagnostic also in cases of elbow instability and stiffness.

LEVEL OF EVIDENCE

Basic science study.

CLINICAL RELEVANCE

The newly proposed indexes are promising tools to improve diagnostic accuracy of coronoid fractures as well as to enhance perioperative diagnostic for elbow instability and stiffness.

Lateral Elbow Laxity Is Affected by the Integrity of the Radial Band of the Lateral Collateral Ligament Complex: A Cadaveric Model With Sequential Releases and Varus Stress Simulating Everyday Activities

BACKGROUND

An elongation of the radial lateral collateral complex (R-LCL) can provoke symptomatic minor instability of the lateral elbow leading to lateral elbow pain. Biomechanical models investigating the effects of elongation and partial or complete lesions of the R-LCL on lateral elbow stability are lacking.

PURPOSE

To evaluate how partial and complete R-LCL release affects radiocapitellar joint stability in a setting of controlled varus load and progressive soft tissue release.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen cadaveric specimens were obtained and mounted on a custom-made support to control elbow flexion and extension and to allow for controlled varus loading. Stress tests were performed on all intact specimens under gravity load alone, a 0.5-kg load applied to the hand, and a 1-kg load applied to the hand. After load application, anteroposterior radiographs were obtained. The following release sequence was applied to all specimens: release of the anterior half of the common extensor origin, pie crusting of the R-LCL, and R-LCL release. After each release, stress tests and radiographs were performed. The varus joint angulation of the elbow (α) was measured by 2 examiners as the main outcome parameter.

RESULTS

Significant changes in α from the initial condition occurred after each release, and a significant effect of varus load on α was documented for all release steps. A significant effect of the releases on α could be documented for all identical varus load conditions. A linear regression model was generated to describe the effect of varus load on α.

CONCLUSION

Varus loads simulating everyday activities produce changes in the varus joint angulation of the elbow already in the intact specimen, which are linearly dependent on the applied moment and persist after release of the lateral stabilizing structures. With progressive load, a pie crusting of the R-LCL is the minimal procedure able to provoke a significant change in the varus joint angulation, and a complete R-LCL release produces additional increase in the varus joint angulation in all testing conditions.

CLINICAL RELEVANCE

These findings confirm the role of the R-LCL as static lateral stabilizer, supporting a pathological model based on its insufficiency and culminating with a symptomatic minor instability of the lateral elbow.

Proximal ulna fractures in adults: A review of diagnosis and management

Proximal ulna fractures are relatively common upper limb injuries, which may represent fragility fractures or result from high-energy trauma. These include fractures of the olecranon, coronoid and associated radial head dislocations. A wide variety of treatment options are available for the management of these injuries that makes the selection of most appropriate treatment difficult. We aim to provide a brief overview of the treatment options for such injuries.

Does sonography allow an objective and reproducible distinction between stable, hypermobile, and unstable elbow joints?

BACKGROUND

The diagnosis of residual or chronic elbow instability is often challenging. Sonography allows a dynamic examination of the elbow joint without any radiation exposure. The purpose of this prospective single-center study was to investigate the application of sonography for the evaluation of ligamentous instabilities of the elbow joint. Therefore, asymptomatic (stable) and acute dislocated (unstable) elbows were examined by sonography.

METHODS

A total of 72 elbows in 36 participants (23 women and 13 men; mean age, 40 ± 17 years [range, 18-82 years]) were examined. Group 1 (G1 [normal]) included 40 unaffected, asymptomatic elbow joints; 28 elbows belonged to 14 voluntary participants (bilateral), whereas 12 asymptomatic elbows belonged to patients who had an acute elbow dislocation (contralateral elbow). Group 2 (G2 [hypermobile]) included 20 hypermobile elbow joints in 10 participants (bilateral), and group 3 (G3 [unstable]) included 12 acute unstable elbow joints without bony lesions. Radiographic assessment included sonography of both elbow joints with standardized measurements of the neutral and stressed radiocapitellar and ulnohumeral distances (calculated as Δ values). Two investigators independently performed all measurements. Additionally, plain radiographs and magnetic resonance imaging of the affected elbow joints were obtained in G3.

RESULTS

On the radial side, the mean radiocapitellar Δ was statistically higher in G3 (2.2 ± 1.6 mm) than in G1 (0.5 ± 0.4 mm, P < .01) or G2 (0.8 ± 0.6 mm, P < .01). G3 also showed an increased ulnohumeral Δ (2.7 ± 0.7 mm) compared with G1 (1.0 ± 0.7 mm, P < .01) or G2 (0.9 ± 0.3 mm, P < .01). No significant differences in the mean radiocapitellar Δ (P = .06) and ulnohumeral Δ (P = .26) were found between G1 and G2. Within G3, Δ was significantly higher at the affected elbow joint than at the contralateral, unaffected elbow joint (P = .04 for the radial side and P = .04 for the ulnar side). The inter-rater correlation coefficient was 0.82 for the radial side and 0.74 for the ulnar side. Patients with collateral ligament injuries, diagnosed on magnetic resonance imaging, showed higher Δ values than those with intact collateral ligaments, although no significant difference was found.

CONCLUSION

Sonography of the elbow joint is a valuable imaging tool for the assessment of ligamentous instability. Nevertheless, a distinction between healthy and hypermobile elbow joints is not possible, and therefore, obtaining a complete clinical history and examination is vital. We further recommend comparing the affected elbow joint with the contralateral side to access intraindividual differences.

Management of anteromedial coronoid fractures according to a protocol focused on instability assessment provides good outcomes with infrequent need for coronoid fixation

BACKGROUND

Anteromedial coronoid fractures (AMCFs) are associated with persistent elbow instability and post-traumatic arthritis if managed incorrectly. It is unclear exactly which AMCFs require surgical intervention and how to make this decision. The aims of this study were to report outcomes of AMCFs managed using a protocol based on reproduction of instability using radiographic and clinical testing and to ascertain a threshold size of AMCF associated with instability.

METHODS

Forty-three AMCFs were studied. Thirty-two patients formed the primary study group (group A). All were treated using a protocol in which the decision to perform coronoid fixation was based on the presence of radiographic or clinical evidence of instability. Functional outcomes (Oxford Elbow Score), radiographic outcomes, complications, and reoperations were collected, and a receiver operating characteristic curve analysis was performed to assess the optimal coronoid fracture height to recommend coronoid fixation. The results were compared with a historical group of 11 patients with AMCFs not treated according to the protocol (group B).

RESULTS

Of the patients, 23 had an isolated AMCF and 20 had a concurrent radial head injury. Complete nonoperative treatment of the elbow was performed in 16 patients (37%) (11 of 32 [34%] in group A vs. 5 of 11 [45%] in group B, P = .46). In 10 patients (23%), only repair of the lateral collateral ligament was performed (9 in group A and 1 in group B), whereas 8 patients (19%) underwent repair of the lateral collateral ligament and radial head fixation or replacement (6 in group A and 2 in group B). Acute coronoid fixation was performed in 9 patients (21%) (6 in group A and 3 in group B). At a mean follow-up of 20 months (range, 12-56 months), group A showed a significantly better Oxford Elbow Score (42 vs. 31, P = .02), lower complication rate (3 of 32 [9%] vs. 8 of 11 [72%], P < .001), and lower reoperation rate (1 of 32 [3%] vs. 6 of 11 [54%], P < .001) than group B. Persistent instability was found in 6 patients in group B and none in group A. The receiver operating characteristic curve analysis demonstrated 6.5 mm to be the optimal AMCF size for surgery to prevent persistent instability.

CONCLUSION

Patients treated according to a protocol in which preoperative reproduction of instability determined the degree of surgical intervention had good clinical and radiographic outcomes. Our study demonstrated that AMCFs > 6.5 mm are likely to be more unstable and require intervention. If these principles are followed, a specifically defined subset of AMCFs can be treated nonsurgically without adverse outcomes.