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Study Design: Experimental repeated-measures study. Objective: To investigate the effect of different extension forces applied to the palm of the hand on electromyographic (EMG) activity of the wrist extensor muscles during hand gripping. Background: Lateral epicondylitis is usually caused by repetitive wrist extension that leads to an overuse injury. The current theory is that the process of lateral epicondylitis begins with an overuse injury that leads to microtearing of the extensor carpi radialis brevis muscle and occasionally the extensor digitorum communis muscle. Use of an external wrist extension force might reduce muscle activity during gripping. Methods: Muscle activity was measured using surface EMG while subjects gripped at an intensity of 10%, 20%, and 30% of the maximum voluntary contraction force without, and with, an applied external wrist extension force of 1%, 2%, and 3% of maximum voluntary contraction. Results: Applying an extension force to the palm of the hand reduced EMG activity of the extensor muscles at the same strength generation during hand gripping. The muscles with the most significant reduction in EMG level, the extensor carpi radialis brevis and extensor digitorum communis, are those muscles that are most often involved with lateral epicondylitis. Conclusions: This study shows that an external extension force reduces EMG activity of the wrist extensor muscles during gripping in healthy volunteers. As the extension force increased, a greater reduction in muscle activity was noted.

Study Design: Semiexperimental study. Objective: To investigate the effect of an external wrist extension force on extensor muscle activity during hand gripping in patients with lateral epicondylalgia. Background: Lateral epicondylalgia or ''tennis elbow'' is a common, often disabling ailment affecting millions of people. An optimal treatment strategy remains to be identified. The use of an external wrist extension force may reduce the extensor muscle activity during gripping in these patients. Methods: Muscle activity of the extensor carpi radialis brevis (ECRB), extensor digitorum communis (EDC), and extensor carpi radialis longus (ECRL) was measured using surface EMG. Subjects gripped at an intensity of 10%, 20%, and 30% of the maximum voluntary contraction (MVC) force with and without the dynamic extensor brace and with and without an applied external wrist extension force of 1%, 2%, and 3% of MVC. Results: At all levels of MVC gripping, the EMG signal of the ECRB and EDC were significantly lower for gripping with than without brace. An extension force of 3% of the MVC force significantly reduced the EMG signal of all muscles in almost all measurement conditions. Conclusions: The results of this study indicate that the dynamic extensor brace as well as the external extension force significantly reduced the EMG signal of the wrist extensor muscles during gripping in patients with lateral epicondylalgia. Based on these results, the dynamic extensor brace could be a promising new intervention for lateral epicondylalgia.

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Chronic pain in women after breast augmentation: Prevalence, predictive factors and quality of life Chronic pain is a common complaint after surgery (Macrae, 2001;Kehlet et al., 2006). Because little is known about chronic pain after cosmetic surgery we investigated the prevalence of chronic pain after breast augmentation, tried to identify possible characteristics of patients developing chronic pain, measured cosmetic satisfaction after surgery and determined quality of life. We performed a retrospective, mono-center study and used a questionnaire which included questions about presence of pain, biometric characteristics, a cosmetic satisfaction VAS, the McGill Pain Questionnaire and the RAND-36 Health Survey and we contacted 494 female patients who underwent breast augmentation from 2002 to 2005. We defined chronic post-surgery pain, according to the International Association for the Study of Pain, as ''persisting continuous or intermittent pain for more than 3 months after surgery and different from the preoperative pain" (IASP, 1986). The unpaired Student's T-test and ANOVA were used for intergroup comparisons. We received 317 questionnaires (64%) of which 265 were complete and suitable for analysis (54%) with a mean follow-up of 27 months (SD ± 10 months). We found a point prevalence of 25% for chronic pain and a cumulative prevalence of 31%. Three smaller studies showed similar results: 38% (Wallace et al., 1996), 13% (Romundstad et al., 2006) and 18% (Hölmich et al., 2007) of patients reported chronic breast pain after prosthetic breast augmentation. Patients with chronic pain were younger (p = 0.008) and smaller (p = 0.016). Reported cosmetic satisfaction was less in patients with chronic pain (p < 0.001). Of the patients with chronic pain 9% reported a VAS for pain of P50 mm. Reported quality of life was inferior in patients with chronic pain vs. patients without pain (p < 0.05) regarding physical and social functioning, physical limitations and mental health. See Table 1 Contents lists available at ScienceDirectEuropean Journal of Pain j o u r n a l h o m e p a g e : w w w . E u r op e a n J o u r n a l P a i n . c o m satisfaction and quality of life are less in patients with chronic pain after breast augmentation compared to patients without chronic pain.