NEW YORK (

TheStreet

) -- Strong earnings reports were powering small-caps on Thursday. The stock of

IPG Photonics

(IPGP) - Get Report

was the biggest winner in the small-cap space, up 30% to $45.09, after the laser manufacturer said it expects to report fourth-quarter results above its previous forecast.

The company said it expects profit between 53 cents and 56 cents per share on about $100 million in sales. Previously, the company said it expected profit between 30 cents and 35 cents per share on revenue between $80 million and $86 million. Analysts were expecting profits of 36 cents per share on revenues of $85 million.

Hanger Orthopedic

(HGR)

saw its shares climb 19% to $4.36 on volumes of over 1 million after its adjusted fourth-quarter profit of 52 cents beat estimates by 12 cents.

Shares of

Select Comfort

(SCSS)

jumped 12% to $11.79 after the mattress maker topped Wall Street's profit view for its latest quarterly results and gave a strong outlook for fiscal 2011.

The company earned $7.1 million, or 13 cents a share, on sales of $148.7 million for the three months ended Dec. 31, ahead of the average estimate of analysts for a profit of 10 cents a share on sales of $143.7 million in the quarter.

Communications technology company

Arris

(ARRS) - Get Report

reported a 66% drop in profits to $11.3 million or 9 cents per share. Adjusted profit came in at 19 cents, beating estimates by 2 cents. The company, which provides products that enable high-speed data and video traffic, forecast first-quarter earnings of 14-18 cents per share, excluding items, on revenue of $260 million to $280 million.

Shares of

Clearwire

(CLWR)

were up 3.5% at $5.70 after it said Wednesday that it plans to put a stop to its retail expansion plans and focus on its existing network. Expansion plans drained the cash-strapped company of resources. Analysts also hope that the move would persuade partner

Sprint Nextel

(S) - Get Report

to pump more money into the company, according to a

Bloomberg

report.

Shares of

Sequenom

(SQNM)

were up 9% on unusually high volumes. The company announced that it published a key study about its Down syndrome prenatal detection test in the American Journal of Obstetrics and Gynecology.

Shares of

Open Table

(OPEN)

and

JA Solar

(JASO)

were other notable gainers on Thursday's trading.

-- Written by Shanthi Bharatwaj in New York

>To contact the writer of this article, click here:

Shanthi Bharatwaj

.

>To follow the writer on Twitter, go to

http://twitter.com/shavenk

.

>To submit a news tip, send an email to:

tips@thestreet.com

.

Disclosure: TheStreet's editorial policy prohibits staff editors and reporters from holding positions in any individual stocks.