ATI Physician Therapy has picked up North River Physical Therapy.

Chattanooga, Tenn.-based North River specializes in orthopedic rehabilitation and sports medicine. The company has eight clinic practices. Terms of the deal were not disclosed.

ATI Provides orthopedic rehabilitation services through more than 250 clinics in Illinois, Indiana, Wisconsin, Michigan, Ohio, Maryland, Pennsylvania, Delaware, Georgia and Tennessee.

The buyer is backed by private equity firm KRG Capital partners, headquartered in Denver. The firm has about $2 billion in capital under management. The firm is also invested in Aurora Diagnostics, The Focus Corp. and Vention Medical.  KRG currently invests from the firm’s fourth fund, which has $1.96 billion in capital commitments.

FourBridges Capital Advisors advised North River on the deal.

Several other physician groups have been scooped up recently, including Northern Westchester Anesthesia Services PC, which Mednax Inc. (NYSE: MD) bought in September, and Physicians Endoscopy, which Pamlico Capital picked up in September.