Does Low-intensity pulsed ultrasound treatment repair articular cartilage injury? A rabbit model study
- Equal contributors
1 Department of Orthopedics, Kaohsiung Veterans General Hospital, Kaohsiung 81346, Taiwan
2 Department of Physical Therapy, Tzu-Hui Institute Technology, Pingtung County 926, Taiwan
3 Department of Orthopedics, Gang-Shang Armed Forces Hospital, Kaohsiung 820, Taiwan
4 Department of Biomedical Engineering, I-Shou University, No.1, Sec. 1, Syuecheng Rd., Kaohsiung City 84001, Dashu District, Taiwan
BMC Musculoskeletal Disorders 2014, 15:36 doi:10.1186/1471-2474-15-36Published: 10 February 2014
Low-intensity pulsed ultrasound (LIPUS) regiment has been used to treat fractures with non-union and to promote bone union in general. The effect of LIPUS on articular cartilage metabolism has been characterized. Yet, the effect of LIPUS to repair articular cartilage injury remains unclear in vivo.
We designed a study to investigate the effect of LIPUS on articular cartilage repairing in a rabbit severe cartilage injury model. Eighteen rabbits were divided into three groups: Sham-operated group, operated group without-LIPUS-treatment, operated group with-LIPUS-treatment (a daily 20-minute treatment for 3 months). Full-thickness cartilage defects were surgically created on the right side distal femoral condyle without intending to penetrate into the subchondral bone, which mimicked severe chondral injury. MR images for experimental joints, morphology grading scale, and histopathological Mankin score were evaluated.
The preliminary results showed that the operated groups with-LIPUS-treatment and without-LIPUS-treatment had significantly higher Mankin score and morphological grading scale compared with the sham-operated group. However, there was no significant difference between the with-LIPUS-treatment and without-LIPUS-treatment groups. Cartilage defects filled with proliferative tissue were observed in the with-LIPUS-treatment group grossly and under MR images, however which presented less up-take under Alcian blue stain. Furthermore, no new deposition of type II collagen or proliferation of chondrocyte was observed over the cartilage defect after LIPUS treatment.
LIPUS has no significant therapeutic potential in treating severe articular cartilage injury in our animal study.