Mesenchymal stem cells isolated from both distal femurs of patients with unilateral trauma or osteoarthritis of the knee exhibit similar in-vitro ability of bone formation.

BACKGROUND: Bone fractures are a common cause of hospital admission. Currently, treatment consists of conservative regimens or operation. However, regenerative medicine introduces a possible new addition to established treatments. Evidence suggests that application of autologous mesenchymal stem cells can enhance bone regeneration, by differentiating into osteoblasts. This study investigates whether mesenchymal stem cells, isolated from bone marrow in sites of trauma or osteoarthritis, exhibit reduced proliferation and osteogenic differentiation in-vitro, compared to stem cells isolated from non-traumatic and non-osteoarthritic sites. If these pathologies are detrimental to the quality, clinicians should prioritize bone marrow from unafflicted sites. METHODS: 17 patients were enrolled. 7 had recent unilateral trauma to the knee, requiring arthroscopy. 10 had x-ray verified unilateral osteoarthritis of the knee and were scheduled for arthroplasty. Stem cells were isolated from bone marrow aspirated perioperatively from both distal femurs. In-vitro osteogenic activity was assessed through alkaline phosphatase measurement, RNA-expression and alizarin red staining. Proliferation was measured using a growth curve. RESULTS: 29 out of 34 primary cultures were successful, forming colonies with characteristic stem cell-morphology. There was no difference in mononuclear cell yield of aspirates or stem cell-yield from primary culture between non-osteoarthritic and arthritic knees or non-traumatic and traumatic knees. There was no significant difference in in-vitro osteogenic capability or proliferation. CONCLUSION: Our findings suggest that stem cells from sites afflicted by osteoarthritis or trauma can be utilized for bone regeneration with identical results as MSCs isolated from non-traumatic and non-osteoarthritic sites. However, clinical studies are needed to confirm this assumption.

A rare case of localised pigmented villonodular synovitis in the knee of a 24-year-old female soccer player: diagnosis, management and summary of tenosynovial giant cell tumours.

Localised pigmented villonodular synovitis (PVNS) of the knee is a rare diagnosis, with clinical signs and symptoms mimicking meniscal damage or other common knee injuries.We report the case of a 24-year-old female soccer player, seeking treatment after 7 months of persisting knee pain. Additionally, we present an overview of tenosynovial giant cell tumours.On examination, the patient was found to have tenderness in the medial joint space of the knee. MRI revealed a heterogeneous formation in the central part of the knee. The formation was completely enucleated arthroscopically, histological analyses confirmed the diagnosis of localised PVNS. The patient was subsequently free of symptoms with no signs of recurrence on MRI and had resumed soccer practice at the 1-year follow-up appointment.