NEW YORK ( TheStreet) -- Several stocks trading near $5 were moving on above-average volume during Monday's session. Merge Healthcare ( MRGE) fell by 18 cents, or 8.4%, to $1.97 after Amicas ( AMCS) said its board of directors has determined that Merge Healthcare acquisition proposal is "superior" to a merger plan from Thoma Bravo. Merge offered $6.05 per share for all outstanding shares of Amicas, which was above Thoma Bravo's bid of $5.35 per share. Merge's daily volume topped 359,000 shares, compared to the 50-day average daily volume of 217,000, according to the Nasdaq. Wave Systems ( WAVX) rallied by 93 cents, or 24.5%, to $4.73 in the absence of any company-specific news. Investors posting on Internet message boards argued that Wave Systems was trading here on sheer momentum a week before reporting fourth-quarter results. Bearish traders added that the breakout is overextended, and that the parabolic movement in the stock means that a selloff is imminent. Volume topped 2.22 million shares, compared to the 50-day average daily volume of 517,000. Sport Chalet ( SPCHA) jumped by 57 cents, or 27.5%, to $2.64 after Needham analysts upgraded the stock to strong buy from hold with a price target of $7. The analysts argued that recent results from the sporting goods retailer indicated that a recovery may be underway, and that investors will miss a sharp rise in share price if they wait for more evidence. Volume topped 76,000 shares, compared to the 50-day average daily volume of 4,700. USEC ( USU) gained 57 cents, or 13.1%, to $4.93 after the uranium supplier reported a fourth-quarter profit of 31 cents a share, nearly doubling the average of two analyst estimates. USEC also offered better-than-expected revenue guidance for 2010. Volume topped 3.3 million shares, compared to the three-month average daily volume of 1.63 million, according to Yahoo! Finance. -- Written by Robert Holmes in Boston. Check out all of Monday's high-volume, under-$5 stocks at the Dollar Store Follow Robert Holmes on Twitter and become a fan of TheStreet.com on Facebook.