The Combined Use of Cryopreserved Recycled Bone and Free Vascularised Fibula Graft in Limb-Salvage Surgery: ″The Bone in the Bun″ Technique (Hot Dog Technique) Harzem Ozger, Mustafa Sungur, Bugra Alpan, Alauddin Kochai, Levent Eralp Istanbul University Istanbul Faculty of Medicine Department of Orthopsedics and Traumatology

? Recycled bone + Amputation ? Rotationplasty ? Megaprosthesis ? Biological reconstruction ? Massive allograft Recycled bone: Autoclaving Irradiation Pasteurization Cryopreservation FVFG Composites Massive allograft + Recycled bone + ? There are many ways to repair a bone defect but our preferred method for biological reconstruction is combination of cryopreserved bone and free vascular fibula graft.

Massive Allograft - alone Disadvantages Avascular Consolidation too late Expensive Immune response Infection Resorption Availability Socioreligious problems Anatomical incongruency 6 yo male, ES Proximal 2/3 of femur 10 yrs follow-up NED Ewing sarcoma of 2/3 proximal femur. Reconstructed with massive allograft. good primary mechanical strength but no blood supply. Consolidation takes too long. May end up as sequestrum. Advantages Early postop. Xray. Mass. allograft fixed w/ IM nail Primary mechanical strength good +2 yrs Extracortical bone bridging but no union +3 yrs Antiobiotic rod due to infection Allograft removed due to infection

Free Vascularized Fibular Graft - alone Advantages - Easily available Vascular Rapid healing Disadvantages Primary mechanical strength insufficient 14 f, ES FVFG alone! + 7 yrs follow-up NED Ewing’s sarcoma of the proximal femur. Vascularised fibula alone. Rapid healing but sufficient mechanical strength takes 4 years - too long. 4 yrs for full consolidation and full weight bearing – TOO LONG

WHY FROZEN HOT DOG?

Recycled Bone - cryopreservation Availability Anatomical congruence Autogenous proteins, growth factors, cytokines Almost no cost (only recycling cost) No immune reaction? (cryoimmunological function?) Mechanical strength: Cryopreserved ≅ intact bone Superiorities of cryopreservation: mechanical strength comparable to intact bone easy availability, less expensive, perfect anatomical congruence better osteoinductive and osteoconductive properties.

LN + FVFG = bone in the bun… Technique 1. Tumor resection 2. Harvesting of FVFG 3. Soft tissue stripping 4. Preparation of medullary cavity 5. Preparation of cortical window for FVFG pedicle 6. Liquid Nitrogen treatment Nitrogen tank……………………20 min Room temperature (20°)………15 min Heated saline solution (30°).....10 min 7. Reimplantation + osteosynthesis 8. Insertion of FVFG inside prepared bone segment and anastomosis of pedicle 9. Grafting of osteotomy sites …or ‘hot dog’ soft tissue stripping The stages of preparation of bone in the bun or hot dog tumor resection bone in the bun! LN treatment

Patients and Methods 14 patients, treated between 2005-2009 8 male, 6 female Mean age: 13.9 yrs (6-31) Mean follow-up: 17.1 months (6-46) 9 osteosarcoma, 5 Ewing sarcoma Tumor localization: - distal femur, 8 pts - proximal femur, 2 pts - femur diaphysis: 1 pt, - proximal tibia: 2 pts - tibia mid-diaphysis: 1 pt + 17 mo. 14 patients Mean follow-up: 17.1 months 10 yo male, OS Distal femur 18 mo. follow-up NED

Patients and Methods Recycled bone: cryopreservation for all patients FVFG: - 11 patients: contralateral single strut - 2 patients: bilateral fibula grafts harvested to bridge a defect longer than single fibula - 1 patient: ipsilateral single strut Mean bony defect: 17.2 cm (9.0-27.5) Mean fibular graft length: 18.9 cm (10-28) Plate: 13 pts; IM nail: 1 pt. 10 m, OS Proximal 2/3 femur 43 mo.follow-up NED + 5 mo. + 27 mo. +30 mo. For 2 patients we used bilateral fibula grafts to bridge a defect longer than single fibula

Results Complete consolidation: 8 patients 19 female, OS Distal femur Complete consolidation: 8 patients Mean time for consolidation: 13.4 months (9-19) 5 patients awaiting consolidation -mean follow-up: 7.6 months (6-12) No union in 1 pt (29 months follow-up; intramedullary nail) Complications: - implant failure: 3 pts - local recurrence: 1 pt. ( non responding to tx, synchron. multi-met) - deep infection: 1 pt (complete healing w/ antib., debr. + VAC) Mean time for consolidation: 13.4 months Our complications are - implant failure in 3 patients - local recurrence in 1 patient. Did not respond to treatment, had synchronous multiple-mets. - deep infection in 1 patient which completely healed with treatment 10 male, ES Distal femur Full wt bearing and very good knee ROM at 15 mo. postop

Bone in the bun + 2 mo. + 7 mo. + 11 mo. + 19 mo. + 24 mo. 8 yo. ♀, OSG LN + FVFG 24 mo. follow-up NED + 2 mo. + 7 mo. + 11 mo. + 19 mo. + 24 mo. osteosarcoma of distal femur Reconstructed with HOTDOG technique. Plate was broken at 11 months and revision was performed. Full consolidation at 19 months

Bone in the bun + 17 months 14 yo. ♀, ES LN + FVFG 23 mo. follow-up NED + 5 mo + 20 mo. Ewing’s sarcoma of proximal tibia. Another HOTDOG application. Knee functions at 17 months postop. Full consolidation at 20 months postop. + 17 months

Bone in the bun + 0 mo. + 3 mo. + 13 mo. + 13 mo. 12 yo. ♂, OSG LN + double FVFG 17 mo. follow-up DOD Osteosarcoma of distal ¾ femur. Length of single fibula was not enough so reconstructed with two fibulas. + 0 mo. + 3 mo. + 13 mo. + 13 mo.

Bone in the bun 11 ♀, ES Healed pathological fx LN + double FVFG + 6 mo follow-up NED Ewing sarcoma of femur presented with pathological fracture. 28 cm. bone segment was resected.

Bone in the bun + 5 mo. R R Bone scan at 3 mo. postop Two fibular grafts used for reconstruction. Recycled bone had to be osteotomized due to deformity. Bone scan at 3 mo. postop shows good uptake, FVFGs are alive.

Conclusion Cryopreserved recycled bone: - readily available - cheap - anatomically congruent - good mechanical strength BUT - DEAD bone - prolonged consolidation time Cryopreserved recycled bone is strong but dead…

Conclusion FVFG: - LIVING bone - rapid union BUT - poor mechanical strength Vascularized fibula graft is alive but weak

Solution Combination (HOTDOG) - faster consolidation - greater mechanical strength Hotdog is strong and alive… thank you for your attention

Thank you for your attention…