Individual Evaluation of the Common Extensor Tendon and Lateral Collateral Ligament Improves the Severity Diagnostic Accuracy of Magnetic Resonance Imaging for Lateral Epicondylitis

Ultrasound of Lateral Epicondylitis

Clinical findings are generally sufficient to make the diagnosis of lateral epicondylitis of the elbow. Ultrasound (US), in conjunction with standard radiography, is a simple and cost-effective way to confirm the diagnosis, and it is also useful for eliminating most differential diagnoses and guiding treatment.US analysis of the muscle bodies and tendon laminae of the lateral epicondyle muscles, starting distally at the wrist and extending up to the lateral epicondyle, assists in understanding the complex fibrous architecture of the proximal tendons inserting on the lateral epicondyle. Pain when the US probe passes over an area of hypoechoic tendinosis, hyperemia in Doppler mode, and an intratendinous split are the signs to look for in patients. US helps guide needling or injection by targeting pathologic areas.Other examinations (computed tomography arthrogram and magnetic resonance imaging) are used as a second line of defense, particularly in cases of bone or joint pathology.

Magnetic resonance imaging predicts outcomes of conservative treatment in patients with lateral epicondylitis

BACKGROUND

The clinical validity of positive magnetic resonance imaging findings in lateral epicondylitis is controversial. We hypothesized that magnetic resonance imaging could predict the outcome of conservative treatment. This study determined the relationship between magnetic resonance imaging-defined disease severity and treatment outcomes in patients with lateral epicondylitis.

METHODS

This retrospective single-cohort study included 43 conservatively managed and 50 surgically treated patients with lateral epicondylitis. The magnetic resonance imaging scores and clinical outcomes were examined six months post-treatment, and the former was compared between patients with good and poor treatment outcomes. We developed operating characteristic curves of magnetic resonance imaging scores for treatment outcomes, and divided patients into magnetic resonance imaging-mild and severe groups according to the obtained cut-off value of the scores. We compared the outcomes of conservative treatment with that of surgery for each magnetic resonance imaging severity.

RESULTS

Twenty-nine (67.4%) conservatively treated patients had good outcomes, while 14 (32.6%) had poor outcomes. The magnetic resonance imaging score was higher in patients with poor outcomes; the cut-off value was 6. Forty-three (86.0%) surgically treated patients had good outcomes, while 7 (14.0%) had poor outcomes. There was no significant difference in magnetic resonance imaging scores between patients with good and poor surgical outcomes. In the magnetic resonance imaging-mild group (score ≤ 5), the outcome showed no significant difference between the conservative and surgical treatment groups. In the magnetic resonance imaging-severe group (score≥6), the outcome of conservative treatment was significantly worse than that of surgical treatment.

CONCLUSIONS

The magnetic resonance imaging score was associated with conservative treatment outcomes. A treatment strategy that includes surgery should be considered for patients with severe magnetic resonance imaging findings; this is not recommended for those with mild magnetic resonance imaging findings. Magnetic resonance imaging is helpful in determining the best treatment strategies for patients with lateral epicondylitis.

LEVEL OF EVIDENCE

III, Retrospective cohort study.

Pathophysiology of sex difference in refractoriness in lateral epicondylitis: Biomechanical study of wrist torque

Eccentric contractions of the wrist extensors worsen lateral epicondylitis (LE), whose pathophysiology may involve sex differences in wrist torque. This study aimed to investigate sex differences in wrist torque in patients with LE. The wrist extension and flexion torques of 22 patients with LE (11 males and 11 females) were measured. Maximum muscle output over time was measured for 20 s, initial torque was defined as muscle strength, and the degree of eccentric contraction was quantified and defined as the eccentric contraction index (ECI). The affected/unaffected side ratio of the wrist extensor, extensor/flexor ratio of muscle strength, and affected/unaffected side difference of ECI between sexes were statistically analyzed. Furthermore, correlations between wrist extensor torque, ECI, and Visual Analog Scale of pain during the examination were evaluated. Females were found to display lower affected/unaffected side ratios of the wrist extensor and wrist extension/flexion ratios for the affected side, compared with males; however, no differences were found in the wrist extension/flexion ratios for the unaffected side in both sexes. Additionally, females presented with larger differences between the affected and unaffected sides in the ECI. Based on correlations between wrist torques, ECI, and pain, females tended to suppress muscle output to prevent pain from eccentric contraction of wrist extensors more than males, which would induce an imbalance in muscle strength of the wrist extensors and flexors. This imbalance may result in chronic eccentric contraction of the wrist extensors with gripping, exacerbating LE.

Differences in Clinical Tests for Assessing Lateral Epicondylitis Elbow in Adults Concerning Their Physical Activity Level: Test Reliability, Accuracy of Ultrasound Imaging, and Relationship with Energy Expenditure

BACKGROUND

Physical activity (PA) can generate physical stress on the musculoskeletal system. Thus, the aim of the current study was to assess the influence of the level of physical activity on clinical tests used in the diagnosis of lateral epicondylitis in adults, intertest reliability and accuracy based on ultrasound imaging, and relationship with energy expenditure.

METHODS

102 adults with lateral epicondylitis were assessed via an International Physical Activity Questionnaire and divided according to PA level: low (n = 19) moderate (n = 42) or high (n = 41). Pain (visual analog scale), Cozen's and Mill's clinical tests and ultrasound exams were performed.

RESULTS

The Cozen's and Mill's tests differed among PA levels. Excellent reliability was found for Mill's test for PA levels and the ultrasound exam (low ICC = 1.0, moderate ICC = 0.82 and high ICC = 0.99). Good reliability was found for Cozen's test (low ICC = 0.80, moderate ICC = 0.74 and high ICC = 0.73), but with significant differences between the ultrasound exams. The Cozen's and Mill's clinical tests had no relationship to the level of energy expenditure for PA levels.

CONCLUSION

Mill's test was reliable and accurate for the PA levels. Intertest reliability was poor for the PA levels. Mill's test proved to be accurate based on the ultrasound exam. The pain caused by the tests was not related to the level of energy expenditure.