Medial tibial subchondral bone is the key target for extracorporeal shockwave therapy in early osteoarthritis of the knee

Wang CJ, Cheng JH, Huang CY, Hsu SL, Lee FY, Yip HK · American Journal of Translational Research

Aiming at the medial tibial subchondral bone gave the largest effects against untreated osteoarthritis: gross osteoarthritic change 38% better, OARSI score 94% better, cartilage defect 45% smaller, bone mineral density 17% higher (all P < 0.001). On micro-CT it raised bone volume (61% against 44% in the tibia, 62% against 53% in the femur), raised yield stress (6 MPa against 4, and 4 MPa against 2) and lowered porosity (38% against 53%, and 37% against 46%). Cell death, proliferation and osteocalcin markers varied by aiming point.

Population

Fifty-six 8-week-old Sprague-Dawley rats in seven groups of eight, osteoarthritis induced surgically, with shockwave aimed at the medial tibia, the lateral tibia, the medial or lateral femur, or combinations

Intervention

Focused shockwave delivered to one of six locations around the knee

Comparator

Untreated osteoarthritic knees and the other aiming points

Limitations

Rats, eight per group, one laboratory — the same Kaohsiung group and device as the other two targeting studies here, so the animal case for aiming at subchondral bone rests largely on one team. Percentage improvements are reported against the untreated osteoarthritic group rather than against sham, so they describe how much of the induced damage was averted, not a return to a normal joint. Funded by the Chang Gung Medical Foundation; this paper declares no conflict of interest, where its two companion papers disclose an author's SANUWAVE advisory role.