The acquisition expands TPG’s California footprint to 74 clinics, one of the largest fully-integrated outpatient physical therapy providers in the state
For Immediate Release:
Bolingbrook, IL – August 14, 2025 – Therapy Partners Group (TPG), a leading provider of outpatient physical therapy services, today announced the acquisition of the physical therapy department of Orthopaedic Specialty Institute Medical Group of Orange County (OSI), a respected California general partnership.
The single-clinic physical therapy department, located in Orange, CA, will be rebranded under TPG’s ProSport PT brand, with the existing clinical team transitioning to TPG, ensuring patients receive the same great care, only under a new name and with the expanded resources of TPG. This strategic addition strengthens TPG’s footprint in Orange County and expands patient access to high-quality rehabilitative care under the ProSport PT name.
“We are excited to welcome the OSI therapy team aboard TPG under our ProSport PT brand. The team members at OSI are known for taking great care of their patients and community and are a great fit for the TPG culture,” said TPG CEO Brent Mack.
One of Southern California’s premier orthopedic medical groups, OSI offers a wide array of advanced orthopedic and rehabilitation services—including spine surgery, sports medicine, joint replacement, and rehabilitation therapy. The OSI physical therapy department, staffed by a long-tenured clinical team, has cultivated a reputation for delivering consistent, patient-centered care.
TPG initially entered the Orange County market in 2022 through the acquisition of ProSport PT, a well-established local brand founded by Joe Donohue in 1992. With seven clinic locations at the time of acquisition, TPG has expanded the ProSport PT brand over the past 3 years, opening four DeNovo clinics and completing two tuck-in acquisitions—including the OSI physical therapy department—bringing the ProSport PT footprint to 13 clinics across Orange County today.
“OSI is incredibly excited about this next phase in the development of our physical therapy department,” said Dr. Robert Grumet, orthopedic surgeon and partner at OSI. “The patient-centered culture and local reputation established by our amazing physical therapists and PT aides, combined with the knowledge and expertise of the ProSport PT brand and Therapy Partners Group, will elevate the quality of care and the resources available to our patients in their recovery.”
Formed in 2019, Therapy Partners Group is a physical therapist-led company building a fully integrated network of best-in-class physical therapy brands. With headquarters in Bolingbrook, Illinois, and Modesto, California, the company operates more than 140 clinics across seven states. TPG is a portfolio company of the Chicago-based investment group Shore Capital Partners. To learn more, please visit www.therapy partnersgroup.com or www.shorecp.com.
Media Contact:
Paul Coyne, Chief Development Officer Therapy Partners Group | pcoyne@tpgpt.com
