Upper limb position affects pain-free grip strength in individuals with lateral elbow tendinopathy

A New Test for the Advanced Diagnosis of Lateral Elbow Tendinopathy with Concomitant Intrasubstance Tear: Failure to Resist Extension Effort (the Free Test)

Background

Lateral elbow tendinopathy (LET) is one of the most common causes of musculoskeletal pain. The diagnosis is based on the clinical history and different physical maneuvers. Ultrasound (US) is a complementary diagnostic method to detect degenerative tendon changes and intrasubstance tears (IST). To date, there is no available physical maneuver to identify an IST in patients with LET.

Aim

To evaluate the diagnostic accuracy of an index test to detect an IST confirmed by ultrasound in patients with LET.

Methods

A diagnostic retrospective study was performed. Patients who presented medical records with LET were recruited. Two orthopaedic surgeons developed the physical maneuver. The index test was considered positive when the position failed to resist the wrist extension maximum effort. Clinical findings were associated with confirmation of IST by US. Data were calculated using diagnostic accuracy, sensitivity, and specificity with 95% confidence intervals.

Results

Thirty-nine patients (39 elbows) were analyzed, 25 (64%) women and 14 (36%) men, with an average age of 47.7 years. The index test's sensitivity was 0.86 (95% CI, 0.67-0.96). Accuracy was 0.79 (95% CI, 0.64-0.91), and the specificity was 0.64 (95% CI, 0.31-0.89).

Conclusion

The index test presented very good sensitivity and good accuracy in patients with LET with US diagnostic confirmation of IST.

Level of Evidence

Diagnostic study, Level III.

Effects of multidirectional elastic tape on forearm muscle activity and wrist extension during submaximal gripping in individuals with lateral elbow tendinopathy: A randomised crossover trial

BACKGROUND

Lateral elbow tendinopathy is associated with changes to forearm muscle activity and wrist posture during gripping. Multidirectional elastic tape is thought to exert a deloading effect on underlying musculotendinous structures, which could potentially alter muscle activity or wrist posture.

METHODS

This single-blinded randomised crossover trial compared the immediate effects of tensioned multidirectional elastic tape, untensioned control tape, and no tape, in individuals with lateral elbow tendinopathy. Muscle activity of extensor carpi radialis longus and brevis, extensor carpi ulnaris, and extensor digitorum and wrist extension angle were recorded during a submaximal gripping task. Muscle activity was normalised to the maximum amplitude recorded during maximal grip. Change scores were calculated (post-condition minus baseline). Repeated-measure analyses of variance were used to examine between-condition differences.

FINDINGS

27 participants (16 males, mean age (SD): 48.6 (11.9) years) underwent all conditions. Extensor digitorum muscle activity was reduced during the multidirectional elastic tape, compared to control tape and no tape (MD -5.6% [95%CI: -9.9 to -1.3], MD -5.8% [95%CI: -10.2 to -1.4], respectively). Extensor carpi ulnaris muscle activity was reduced during the multidirectional elastic tape, compared to the control tape (mean difference [MD] -3.2% [95%CI: -5.3 to -1.1]), but increased during the control tape, compared to the no tape (MD 2.9% [95%CI: 0.8 to 5.0]). No differences were observed in extensor carpi radialis brevis or longus muscle activity, or extension wrist angle between conditions.

INTERPRETATION

A decreased in extensor carpi ulnaris and extensor digitorum muscle activity during multidirectional elastic tape may be evidence of a deloading effect during submaximal gripping.