Skip to main content

Challenging for cartilage repair


When we look back on the past 15-year history of cartilage repair, it is clear that remarkable progress has been made in this area. There is no doubt that a lot of studies have been carried out on cartilage repair and chondrocytes since Brittebergs' report on ACI in 1994 [1]. I would like to introduce our multi-pronged approach to cartilage repair. After the 1994 report [1], we performed implantation of tissue-engineered cartilage made ex vivo for the treatment of osteochondral defects of the joints, to avoid the leakage of grafted cultured chondrocytes in suspension [2, 3]. Sixty knees of 57 patients with full-thickness cartilage defects were followed-up over 5 years. The clinical rating improved significantly after implantation of tissue-engineered cartilage and was maintained for an average of 8.3 years. The arthroscopic findings 2 years after implantation were graded as normal or nearly normal according to the ICRS scale in more than 90% of patients. Biomechanically, stiffness of the graft almost equaled the surrounding normal cartilage (87.9 ~102.5%) 2 years after implantation.

The next contribution to our variety of cartilage repair methods, was the minimally invasive approach using a tissue-engineered chondral plug. New scaffolds, consisting of a type I collagen sponge and surrounding PLLA mesh [4] or interconnected porous calcium hydroxyapatite ceramic [5], were demonstrated to comprise an effective minimally invasive approach.

The bone marrow stimulating technique under arthroscopy is another minimally invasive technique which is a well accepted procedure for large osteochondral defects. However, there are two potential weak points when inducing hyaline cartilage. One is a compressive overload on the drilled or microfractured area in the early stage after surgery. In order to reduce this early stage overload, we have developed external fixators which allow almost full ROM with joint distraction for clinical cases, based on an animal study [6]. This apparatus has been successfully used for 12 patients, each with a large cartilage defect [7]. Another weak point is a small number of mesenchymal stem cells obtained from drilled holes which are used for chondrogenesis. An injection of cultured MSCs into the joint has been demonstrated to be effective for cartilage defects in rats [8]. The combined approach should be adopted for large defects in the near future.

However, the most optimal procedure for the repair cartilage defects is simply an injection of cytokines or growth factors and cells. Our planned novel approach for the future is to use a cell delivery system using an external magnetic field. Our procedure involves using autologous bone marrow mesenchymal stem cells attached to small-sized magnetic beads and an external magnetic field. For successful cartilage repair, it is ideal to effectively attract injected mesenchymal stem cells to a desired portion in the knee joint (osteochondral defect) using an external magnet force [9]. We believe that this novel system is also effective in the treatment of brain or spinal cord injury and for malignant tumors, using natural killer cells instead of autologous bone marrow mesenchymal stem cells.

Current clinical results following cartilage repair remain unsatisfactory. We need to perform several prospective studies, in order to obtain solid evidence from each procedure's individual indication. From this, decisions can be made to enhance cartilage regeneration with hyaline cartilage. However, continuous efforts in experimental research, based on completely novel and challenging ideas, are vital in order to achieve a breakthrough in cartilage surgery. I hope that such a breakthrough will come soon.


  1. Brittberg M, Lindahl A, Nilsson A, Ohlsson C, Isaksson O, Peterson L: Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation. N Engl J Med. 1994, 331: 889-895. 10.1056/NEJM199410063311401.

    Article  CAS  PubMed  Google Scholar 

  2. Ochi M, Uchio Y, Tobita M, Kuriwaka M: Current concepts in tissue engineering technique for repair of cartilage defect. Artif Organs. 2001, 25: 172-179. 10.1046/j.1525-1594.2001.025003172.x.

    Article  CAS  PubMed  Google Scholar 

  3. Ochi M, Uchio Y, Kawasaki K, Wakitani S, Iwasa J: Transplantation of cartilage-like tissue made by tissue engineering in the treatment of cartilage defects of the knee. J Bone Joint Surg Br. 2002, 84: 571-578. 10.1302/0301-620X.84B4.11947.

    Article  CAS  PubMed  Google Scholar 

  4. Ito Y, Ochi M, Adachi N, Sugawara K, Yanada S, Ikada Y, Ronakorn P: Repair of osteochondral defect with tissue-engineered chondral plug in a rabbit model. Arthroscopy. 2005, 21: 1155-1163.

    Article  PubMed  Google Scholar 

  5. Ito Y, Adachi N, Nakamae A, Yanada S, Ochi M: Transplantation of tissue-engineered osteochondral plug using cultured chondrocytes and interconnected porous calcium hydroxyapatite ceramic cylindrical plugs to treat osteochondral degects in a rabbit model. Artif Organs. 2008, 32: 36-44.

    PubMed  Google Scholar 

  6. Kajiwara R, Ishida O, Kawasaki K, Adachi N, Yasunaga Y, Ochi M: Effective repair of a fresh osteochondral defect in the rabbit knee joint by articulated joint distraction following subchondral drilling. J Orthop Res. 2005, 23: 909-915. 10.1016/j.orthres.2004.12.003.

    Article  PubMed  Google Scholar 

  7. Deie M, Ochi M, Adachi N, Kajiwara R, Kanaya A: A new articulated distraction arthroplasty device for treatment of the osteoarthritic knee joint: a preliminary report. Arthroscopy. 2007, 23: 833-838.

    Article  PubMed  Google Scholar 

  8. Nishimori M, Deie M, Kanaya A, Exham H, Adachi N, Ochi M: A bone marrow-stimulating procedure enhanced by cultured allogenic bone marrow mesenchymal stromal cells. J Bone Joint Surg Br. 2006, 88: 1236-1244. 10.1302/0301-620X.88B9.17810.

    Article  CAS  PubMed  Google Scholar 

  9. Kobayashi T, Ochi M, Yanada S, Ishikawa M, Adachi N, Deie M, Arihiro K: A novel cell delivery system using magnetically labeled mesenchymal stem cells and an external magnetic device for clinical cartilage repair. Arthroscopy. 2008, 24: 69-76.

    Article  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Mitsuo Ochi.

Rights and permissions

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Ochi, M. Challenging for cartilage repair. BMC Sports Sci Med Rehabil 1, 13 (2009).

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: