Why don’t the stem cells in the upper thigh bone of the hip repair the damage to the bone they live in?

Researchers in France led by Philippe Hernigou of the Department of Orthopaedic Surgery, University Paris East have some answers in their recent 2017 study.[1]

The French team suggests that the relationships between native bone marrow and the degenerating hip complex cause vast changes in the native stem cells. This is the degenerative joint disease process, changing the joint from healthy to diseased and compromising the stem cells present in the hip.

  • The degenerative process creates fatty marrow that inhibit healing.
  • Abnormalities of the osteogenic stem cells are also present in the bone marrow of some of these patients which could be caused by injury, disease or past steroid injections.

Because of this diseased hip environment, blood flow is restricted and this may be a predisposing factor for osteonecrosis since changes in bone marrow and bone remodeling (repair) are linked.

  • The situation is bone cells are dying and the “stronger” bone cells are being suffocated by lack of blood flow caused by dying bone cells.
  • This causes insufficient bone remodeling because of the small number of progenitor (stem) cells present in the femoral head in these patients.
  • Although both research and clinical studies have shown that dead bone may be replaced by living bone, the osteogenic potential for repair is low in osteonecrosis. This is why people are recommended to hip replacement.

Despite these challenges, Dr. Hernigou cited his earlier research where 189 hips in 116 patients were treated with bone marrow stem cells drawn from their own iliac crest bone at the top of the pelvis.

  • Satisfactory results were achieved in the majority of patients according to improvement in various pain scores and the patient’s ability to avoid hip replacement noted at follow ups 5 to 10 years AFTER treatment.

The French research shows that despite advanced hip disease, bone marrow derived stem cell therapy can repair bone damage in hip osteonecrosis for the long-term. These findings have been supported by other recent research in which investigators speculated that not only could stem cell therapy repair bone damage in hip osteonecrosis, but it could halt the disease acceleration by changing the cellular joint environment to one of healing.[2] In pre-clinical studies, the use of stem cells uniformly demonstrated improvements in osteogenesis (bone fragility) and angiogenesis (blood vessel formation).[3]

Email Dr. Darrow with your questions about hip replacement

1. Hernigou P, Flouzat-Lachaniette CH, Delambre J, Poignard A, Allain J, Chevallier N, Rouard H.Osteonecrosis Repair with Bone Marrow Cell Therapies: State of the Clinical Art. Bone. 2015 Jan;70:102-9. doi: 10.1016/j.bone.2014.04.034. Epub 2014 Jul 10.. [Epub ahead of print] PUBMED ABSTRACT

2. Lau RL, Perruccio AV, Evans HM, Mahomed SR, Mahomed NN, Gandhi R. Stem cell therapy for the treatment of early stage avascular necrosis of the femoral head: a systematic review. BMC Musculoskelet Disord. 2014 May 16;15:156. doi: 10.1186/1471-2474-15-156. PUBMED ABSTRACT

3. Houdek MT, Wyles CC, Martin JR, Sierra RJ. Stem cell treatment for avascular necrosis of the femoral head: current perspectives. Stem Cells Cloning. 2014 Apr 9;7:65-70. eCollection 2014. PUBMED ABSTRACT