Stem Cells International

Stem Cells International / 2020 / Article
Special Issue

Mesenchymal Stem Cells and Regenerative Medicine 2020

View this Special Issue

Research Article | Open Access

Volume 2020 |Article ID 8898145 |

Lorenzo Andreani, Sheila Shytaj, Elisabetta Neri, Fabio Cosseddu, Antonio D’Arienzo, Rodolfo Capanna, "Bone Marrow Concentrate in the Treatment of Aneurysmal Bone Cysts: A Case Series Study", Stem Cells International, vol. 2020, Article ID 8898145, 4 pages, 2020.

Bone Marrow Concentrate in the Treatment of Aneurysmal Bone Cysts: A Case Series Study

Academic Editor: Heinrich Sauer
Received26 Jun 2020
Accepted10 Aug 2020
Published21 Aug 2020


Introduction. A recent attractive option regarding mesenchymal stem cells (MSC) application is the treatment of bone cystic lesions and in particular aneurysmal bone cysts (ABC), in order to stimulate intrinsic healing. We performed a retrospective evaluation of the results obtained at our institution. Methods. The study group consisted of 46 cases with an average follow-up of 33 months. Forty-two patients underwent percutaneous treatment as the first approach; four patients had curettage as first treatment. In all cases, autologous bone marrow concentrate (BMC) was associated too. The healing status was followed up through a plain radiograph 45 days and 2 months after the procedure. Results and Conclusions. At the final follow-up, thirty-six patients healed with a Neer type II aspect, nine healed with a type I aspect, and one patient was not classified having total hip arthroplasty. Bone marrow concentrate is easy to obtain and to manipulate and can be immediately available in a clinical setting. We can assert that the use of BMC must be encouraged being harmless and having an unquestionable high osteogenic and healing potential in bone defects.

1. Introduction

In the past 30 years, many studies have confirmed the potentials and plasticity of the so-called mesenchymal stem cells (MSC): they have been shown to reside within the connective tissues of most organs and can differentiate into osteogenic, adipogenic, and chondrogenic lineages under appropriate conditions [13]. These features have led to an increasing application of MSC in the orthopaedic field, especially when a strong regenerative capacity applied through a minimally invasive approaches is required. A simple method to have MSC is the bone marrow concentrate (BMC) obtained through autologous bone marrow aspiration and centrifugation. Local application of BMC is one of the current available treatments of bone defects and in particular of cystic lesions [4, 5]. Among them aneurysmal bone cysts (ABC) are uncommon osteolytic lesions, usually eccentric, with a hyperplastic behaviour often arising in the long bones of young people, being rare after 30 years of age [6]. The treatment approach to ABC has evolved in the past years ranging from radiotherapy to resection. More recently, less invasive procedures such as complete or partial curettage, and various substance injections seemed to be promising [7, 8]. We performed a retrospective evaluation of the results obtained at our institution after aneurysmal bone cyst percutaneous treatment with application of BMC in order to understand if the use of bone marrow stem cells actually gives benefits.

2. Material and Methods

We present a retrospective study involving 57 patients with diagnosis of aneurysmal bone cyst, treated at our institution between January 2013 and June 2019. The following exclusion criteria were applied: secondary ABC, initial treatment in other institution, and incomplete radiographic evaluation. Eight patients were excluded according to the following criteria: 2 ABC associated to chondroblastoma, 3 patient who had initial treatment in another hospital, and 6 patients for the absence of complete radiographic evaluation available. The study group consisted of 46 patients with an average follow-up of 33 months. Forty-two patients underwent percutaneous treatment as first approach; four patients had curettage as first treatment. The patients enrolled performed a plain radiograph before intervention, and the following radiographic variables were assessed: affected bone, staging according to the Enneking system [9], and location according to the Capanna classification [10]. In all cases, the diagnosis was obtained through a histopathological study of specimens collected intraoperatively. All of the procedures were performed using sedation and local anaesthesia or under general anaesthesia with an aseptic technique. The percutaneous injections were performed introducing a Jamshidi needle, under fluoroscopic guide, into the lesion. The content of the cyst was then aspirated and sent for histopathologic evaluation; subsequently, the chosen drugs were injected into the lesion. The injected substances were : vitamin C, atossisclerol (0, 25%), methylprednisolone acetate, and autologous bone marrow concentrate (BMC). The two lesions treated with curettage were filled with bone chips enriched with the same substances aforementioned. The BMC was obtained through aspiration of bone marrow from the ipsilateral iliac crest and centrifugation in a dedicated RegenKit® device. The healing status was followed up through a plain radiograph 45 days after the procedure and then 2 months after. According to the modified Neer classification [11], the procedure was repeated if no satisfactory healing of the lesion occurred after 2 months, i.e. if the radiolucent area was ≧50% of the lesion diameter or in case of relapse.

3. Results

The mean age at diagnosis was 13.8 with a male prevalence (31 males, 15 females). The anatomical location, collected in Table 1, shows a predominant distribution in the proximal metaphysis of long bones and in the pelvis. The cysts were classified in inactive, active, and aggressive according to the Enneking staging of musculoskeletal tumours as shown in Table 2: they were all active, except for one that was an aggressive lesion. According to the Capanna staging (Table 3), all patients had type II lesions, i.e., central and affecting the entire diameter of the bone, except for two cases having eccentric lesion, defined as type III. Thirty-six patients healed after the first treatment; among them, four had an open curettage and the cavity was filled with bone chips and autologous BMC. Of the remaining ten patients, seven healed with 2 percutaneous injections; of the remaining two, 3 had percutaneous injection and one had a resection with total hip replacement. Healing was assessed using the modified Neer classification (Table 4) used for unicameral bone cyst treatment: at the final follow-up, thirty-six patients healed with a type II aspect, nine healed with a type I aspect, and one patient was not classified having total hip arthroplasty.


Proximal humerus14
Humeral diaphysis8
Femur diaphysis6
Proximal femur13

InactiveIntact, well-defined margins

ActiveIncomplete margins but well-defined lesion
AggressivePoorly defined margins with reactive bone formation

TypeMorphological features

ICentral lesion
IICentral lesion involving the entire bone diameter
IIIEccentric lesion
IVSubperiosteal lesion
VSubperiosteal lesion extending to soft tissues


ICyst healed with radiolucent
IICyst healed with radiolucent of diameter and enough cortical thickness
IIIPersistent cyst with radiolucent of diameter with thin cortical rim
IVRecurrent cysts in the obliterated area or increased residual radiolucent area

4. Discussion

The application of bone marrow concentrate (BMC) in the treatment of aneurysmal bone cysts (ABC) is a quite new procedure. The use of BMC to fill bony defects is well known, with a success rate that seems to be related to the number of progenitors in the graft [12]. ABC are reactive and locally aggressive lesions having osteolytic, hyperplastic, hyperemic, and hemorrhagic features; they are uncommon and rarely present after 30 years of age. Aneurysmal bone cyst-like modifications can be observed also in other pathological conditions, in malignant tumours such as telangiectatic osteosarcoma, and this eventuality must be ruled out through the histological study of specimens [6]. The aim of ABC treatment is to arrest their potentially high destructive capability. In the past years, different approaches have been proposed for ABC treatment ranging from resection to mini-invasive percutaneous procedures, and still today, there is no consensus on the best treatment [1315]. However, the analysis of ABC pathogenesis and natural history, although not completely understood, can be helpful to chose the most appropriate treatment. It was long thought that ABC’s cause was a vascular impairment due to abnormal venous circulation with osteoclast activation and local bone resorption; a more recent clonal theory overtook the vascular theory: the origin of the lesion seems to be associated with a translocation of USP6 oncogene on chromosome 17 [16, 17]. This finding confirms the oncological nature of ABC and therefore their high evolutivity: as for other musculoskeletal tumors, ABC can be classified as inactive, active, and aggressive and their evolution proceeds in phases. The initial osteolysis can evolve to cortical destruction and periosteal reaction creating a bulky bone; the appearance of septa attests a stabilization and remodelling attempt that in a few cases can lead to spontaneous resolution. In other cases, ABC assume an aggressive and destructive behaviour; however, the reason that shifts to a stabilizing or a destructive pattern is still unknown [7, 18]. Delloye et al. were among the first to report two cases of ABC treated with BMC: the rationale underlying this treatment was in the inductive properties of mesenchymal stems cells [19]. Many studies have already confirmed that BMC, particularly, if obtained through iliac crest aspiration, is rich in mesenchymal cells that seem to represent the source of osteoblastic elements during growth, remodelling, and bone reparative processes [2022]. Moreover, ABCs are subject to continuous reparative processes in a cavity filled with blood that provides an ideal environment for mesenchymal cells to express their inductive capacities. Therefore, the aim of our treatment was to induce spontaneous ossification of ABC through a minimally invasive procedure. Currently, there is no consensus on the ideal treatment of ABC. For eccentric and aggressive lesions, located in expendable bones like the proximal fibula or pubic ramus, many authors have advocate resection as treatment of choice, reporting very low recurrence rates [23, 24]. According to other authors, curettage with or without bone grafting seems to be the best choice, reporting acceptable recurrence rates with a much better functional outcome than resection [25, 26]. More recently, in consideration of patients’ young age and with better understanding of ABC pathogenesis, less-invasive procedures are gaining more success: percutaneous embolization, isolated intracystic injection of demineralized bone powder, bone marrow, calcitonin and Ethibloc are some examples [2729]. Docquier and Delloye reported good results inducing ABCs' healing with intralesional implantation, through a mini-invasive access, of a bone paste made of autogenic bone marrow and allogenic bone powder: the goal of this treatment was to interrupt the destructive osteoclastic process and promote spontaneous bone regeneration [7]. In our series, with the technique described, we obtained a full recovery after only one treatment in more than 50% of our cases; the remaining had a maximum of two other procedures except for one patient, affected by a lesion involving the femoral head in contact with the articular cartilage that eventually underwent prosthetic replacement. Only four patients received curettage as first treatment since they had wide lesions ; they both reported a Neer II grade at follow-up. As regards percutaneous approach, we believe that, given the age of patients affected by this condition, the proposed treatment avoids extensive surgery and blood loss and can be repeatable with minor discomfort for the patient. Moreover, we did not report any complication, including superficial or deep infection, fracture, or other adverse reactions, both at the harvest site and at the application site: this confirmed the safety of the procedure used.

Nevertheless, even if the results obtained are promising, the number of cases is exiguous and a larger group is necessary to confirm the validity of this procedure ; perhaps with a greater number of patients a stratification based on anatomical location and cyst dimension would be feasible and would help in the choice of the best treatment.

5. Conclusions

Even if affected by the limitation of a relatively small number of patients, our case series proves that bone marrow concentrate is easy to obtain and to manipulate, and can be immediately available in a clinical setting; it offered good results with no complications. We believe that cavitary lesions like ABCs are ideal settings for using mesenchymal cells since they act as a biological chamber where the healing processes can be potentiated by the presence of blood and growth factors that stimulate differentiation of an osteogenic lineage.

Data Availability

The data sets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Written consent was obtained from all patients included in this study (or their parents for underaged patients).

Conflicts of Interest

The authors declare that they have no competing interests.


  1. A. J. Friedenstein, S. Piatetzky II, and K. V. Petrakova, “Osteogenesis in transplants of bone marrow cells,” Journal of Embryology and Experimental Morphology, vol. 16, no. 3, pp. 381–390, 1966. View at: Google Scholar
  2. A. J. Friedenstein, R. K. Chailakhjan, and K. S. Lalykina, “The development of fibroblast colonies in monolayer cultures of guinea-pig bone marrow and spleen cells,” Cell and Tissue Kinetics, vol. 3, no. 4, pp. 393–403, 1970. View at: Publisher Site | Google Scholar
  3. M. Owen and A. J. Friedenstein, “Stromal stem cells: marrow-derived osteogenic precursors,” Ciba Foundation Symposium, vol. 136, pp. 42–60, 1988. View at: Publisher Site | Google Scholar
  4. P. De Biase, D. A. Campanacci, G. Beltrami et al., “Scaffolds combined with stem cells and growth factors in healing of pseudotumoral lesions of bone,” International Journal of Immunopathology and Pharmacology, vol. 24, Supplement 2, no. 1, pp. 11–15, 2011. View at: Publisher Site | Google Scholar
  5. M. Jäger, M. Herten, U. Fochtmann et al., “Bridging the gap: bone marrow aspiration concentrate reduces autologous bone grafting in osseous defects,” Journal of Orthopaedic Research, vol. 29, no. 2, pp. 173–180, 2011. View at: Publisher Site | Google Scholar
  6. M. Campanacci, Bone and Soft Tissue Tumors, Springer, 2013.
  7. P. L. Docquier and C. Delloye, “Treatment of aneurysmal bone cysts by introduction of demineralized bone and autogenous bone marrow,” The Journal of Bone and Joint Surgery American Volume, vol. 87, no. 10, pp. 2253–2258, 2005. View at: Publisher Site | Google Scholar
  8. J. Cottalorda and S. Bourelle, “Current treatments of primary aneurysmal bone cysts,” Journal of Pediatric Orthopaedics. Part B, vol. 15, no. 3, pp. 155–167, 2006. View at: Publisher Site | Google Scholar
  9. W. F. Enneking, S. S. Spanier, and M. A. Goodman, “A system for the surgical staging of musculoskeletal sarcoma,” Clinical Orthopaedics and Related Research, vol. 153, pp. 106–120, 1980. View at: Publisher Site | Google Scholar
  10. R. Capanna, G. Bettelli, R. Biagini, P. Ruggieri, F. Bertoni, and M. Campanacci, “Aneurysmal cysts of long bones,” Italian Journal of Orthopaedics and Traumatology, vol. 11, no. 4, pp. 409–417, 1985. View at: Google Scholar
  11. C. S. Neer 2nd, K. C. Francis, R. C. Marcove, J. Terz, and P. N. Carbonara, “Treatment of unicameral bone cyst. A follow-up study of one hundred seventy-five cases,” The Journal of Bone and Joint Surgery American Volume, vol. 48, no. 4, pp. 731–745, 1966. View at: Publisher Site | Google Scholar
  12. P. Hernigou, A. Poignard, F. Beaujean, and H. Rouard, “Percutaneous autologous bone-marrow grafting for nonunions influence of the number and concentration of progenitor cells,” The Journal of Bone and Joint Surgery. American Volume, vol. 87, no. 7, pp. 1430–1437, 2005. View at: Publisher Site | Google Scholar
  13. P. Flont, M. Kolacinska-Flont, and K. Niedzielski, “A comparison of cyst wall curettage and en bloc excision in the treatment of aneurysmal bone cysts,” World Journal of Surgical Oncology, vol. 11, p. 109, 2013. View at: Publisher Site | Google Scholar
  14. F. O. Abuhassan and A. O. Shannak, “Subperiosteal resection of aneurysmal bone cysts of the distal fibula,” Journal of Bone and Joint Surgery. British Volume (London), vol. 91-B, no. 9, pp. 1227–1231, 2009. View at: Publisher Site | Google Scholar
  15. N. K. Garg, H. Carty, H. P. Walsh, J. C. Dorgan, and C. E. Bruce, “Percutaneous Ethibloc injection in aneurysmal bone cysts,” Skeletal Radiology, vol. 29, no. 4, pp. 211–216, 2000. View at: Publisher Site | Google Scholar
  16. G. P. Nielsen, J. A. Fletcher, and A. M. Oliveira, “Aneurysmal bone cyst,” in WHO Classification of Tumours of Softtissue and Bone, B. J. A. Fletcher, P. C. W. Hogendoorn, and F. Mertens, Eds., pp. 348-349, IARC, Lyon, 2013. View at: Google Scholar
  17. Y. Ye, L. M. Pringle, A. W. Lau et al., “TRE17/USP6 oncogene translocated in aneurysmal bone cyst induces matrix metalloproteinase production via activation of NF-κB,” Oncogene, vol. 29, no. 25, pp. 3619–3629, 2010. View at: Publisher Site | Google Scholar
  18. J. Malghem, B. Maldague, W. Esselinckx, P. De Nayer, and A. Vincent, “Spontaneous healing of aneurysmal bone cysts. A report of three cases,” The Journal of Bone and Joint Surgery. British volume, vol. 71-B, no. 4, pp. 645–650, 1989. View at: Publisher Site | Google Scholar
  19. C. Delloye, P. De Nayer, J. Malghem, and H. Noel, “Induced healing of aneurysmal bone cysts by demineralized bone particles. A report of two cases,” Archives of Orthopaedic and Trauma Surgery, vol. 115, no. 3-4, pp. 141–145, 1996. View at: Publisher Site | Google Scholar
  20. S. P. Bruder, D. J. Fink, and A. I. Caplan, “Mesenchymal stem cells in bone development, bone repair, and skeletal regenaration therapy,” Journal of Cellular Biochemistry, vol. 56, no. 3, pp. 283–294, 1994. View at: Publisher Site | Google Scholar
  21. M. Owen, “Lineage of osteogenic cells and their relationship to the stromal system,” in Bone and Mineral, W. A. Peck, Ed., vol. 3, pp. 1–25, Elsevier, Amsterdam, 1985. View at: Google Scholar
  22. R. O. Oreffo and J. T. Triffitt, “Future potentials for using osteogenic stem cells and biomaterials in orthopedics,” Bone, vol. 25, no. 2, pp. 5S–9S, 1999. View at: Publisher Site | Google Scholar
  23. M. Campanacci, R. Capanna, and P. Picci, “Unicameral and aneurysmal bone cysts,” Clinical Orthopaedics, vol. 204, pp. 25–36, 1986. View at: Publisher Site | Google Scholar
  24. J. Cottalorda, R. Kohler, and F. Lorge, “Aggressive aneurysmal bone cyst of the humerus in a child,” Revue de Chirurgie Orthopédique et Réparatrice de l'Appareil Moteur, vol. 90, no. 6, pp. 577–580, 2004. View at: Publisher Site | Google Scholar
  25. A. M. Vergel de Dios, J. R. Bond, T. C. Schives, R. A. McLeod, and K. K. Unni, “Aneurysmal bone cyst. A clinicopathologic study of 238 cases,” Cancer, vol. 69, no. 12, pp. 2921–2931, 1992. View at: Publisher Site | Google Scholar
  26. B. P. Tillmann, D. C. Dahlin, P. R. Lipscomb, and J. R. Steewaart, “Aneurysmal bone cysts, analysis of 95 cases,” Mayo Clinic Proceedings, vol. 43, pp. 478–495, 1968. View at: Google Scholar
  27. J. Cottalorda and S. Bourelle, “Aneurysmal bone cyst in 2006,” Revue de Chirurgie Orthopédique et Réparatrice de l'Appareil Moteur, vol. 93, no. 1, pp. 5–16, 2007. View at: Publisher Site | Google Scholar
  28. L. Amendola, L. Simonetti, C. E. Simoes, S. Bandiera, F. de Iure, and S. Boriani, “Aneurysmal bone cyst of the mobile spine: the therapeutic role of embolization,” European Spine Journal, vol. 22, no. 3, pp. 533–541, 2013. View at: Publisher Site | Google Scholar
  29. C. Adamsbaum, E. Mascard, J. M. Guinebretière, G. Kalifa, and J. Dubousset, “Intralesional Ethibloc injections in primary aneurysmal bone cysts: an efficient and safe treatment,” Skeletal Radiology, vol. 32, no. 10, pp. 559–566, 2003. View at: Publisher Site | Google Scholar

Copyright © 2020 Lorenzo Andreani et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

More related articles

 PDF Download Citation Citation
 Download other formatsMore
 Order printed copiesOrder

Related articles

Article of the Year Award: Outstanding research contributions of 2020, as selected by our Chief Editors. Read the winning articles.