Our Weekly Checkup takes the temperature of the medical device industry’s three largest U.S. clusters: Massachusetts, California and Minnesota.

The MassDevice Indices are weighted according to market capitalization, based on the number of shares outstanding for each company from its most recent quarterly report and each Friday’s closing share price.

The Massachusetts index for the week ended March 19 closed at 6.02, down 0.1 percent compared with the prior week. Since Jan. 1, 2009, when we began tracking these companies, the index has risen 35.9 percent.

The Minnesota index for the week ended March 19 closed at 3.92, up 2.8 percent compared with the prior week. Since Jan. 1, 2009, when we began tracking these companies, the index has risen 33.0 percent.

The California index for the week ended March 19 closed at 9.62, down 0.9 percent compared with the prior week. Since Jan. 1, 2009, when we began tracking these companies, the index has risen 126.7 percent.

We also create a composite index of the three regional indices and compare it with four other indices (the S&P 500, the Dow Jones Industrial Average, the Dow’s IHI medical devices index and the NASDAQ exchange):

The Weekly Checkup also compares Monday morning’s opening share prices with their value when the markets close Friday afternoon to calculate the biggest gainers and losers.

Here are the 20 firms that posted the biggest share price gains and losses during the week ended March 19:

The 10 biggest gainers:

1. NMT Medical Inc.: 24.4% (open $3.49; close $4.34)
2. Cardiogenesis Corp.: 16.7% (open $0.30; close $0.35)
3. Cardica Inc.: 16.5% (open $1.70; close $1.98)
4. BioSphere Medical Inc.: 11.9% (open $2.68; close $3.00)
5. Boston Scientific Corp.: 11.2% (open $6.41; close $7.13)
6. Vision-Sciences Inc.: 11.2% (open $0.98; close $1.09)
7. Thermage Inc. (Solta Medical Inc.): 10.5% (open $2.00; close $2.21)
8. Integrated Surgical Systems Inc.: 10.0% (open $0.30; close $0.33)
9. Biolase Technology Inc.: 9.9% (open $1.92; close $2.11)
10. Cynosure Inc.: 7.9% (open $10.02; close $10.81)

Sources: Google Finance and Yahoo! Finance.

And the 10 biggest losers:

1. Intraop Medical Corp.: -43.6% (open $0.39; close $0.22)
2. World Heart Inc.: -21.8% (open $2.71; close $2.12)
3. American Superconductor Corp.: -15.5% (open $30.11; close $25.44)
4. Acusphere Inc.: -14.3% (open $0.07; close $0.06)
5. Enteromedics Inc.: -12.7% (open $0.63; close $0.55)
6. Cytori Therapeutics Inc.: -12.6% (open $5.49; close $4.80)
7. Interleukin Genetics Inc.: -12.0% (open $1.00; close $0.88)
8. Viking Systems Inc.: -11.1% (open $0.18; close $0.16)
9. American Shared Hospital Services: -10.7% (open $2.98; close $2.66)
10. Oculus Innovative Sciences Inc. (Micromed): -10.7% (open $2.44; close $2.18)

Sources: Google Finance and Yahoo! Finance.

Disclaimer: MassDevice.com’s rankings do not reflect an opinion of companies’ health, prospects or viability. They are intended to provide a snapshot of publicly traded medical device companies and in no way constitute a recommendation to buy or sell any particular security, portfolio of securities, transaction or investment strategy.