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Total calcaneal reconstruction using a massive bone allograft and a distally pedicled osteocutaneous fibula flap: A novel technique to prevent amputation after calcaneal malignancy

  • Nizar Hamrouni
    Correspondence
    Corresponding author at: Inge Lehmannsvej 6, 2100 Copenhagen, Denmark.
    Affiliations
    Department of Plastic Surgery and Burns Treatment, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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  • Jens Hjermind Højvig
    Affiliations
    Department of Plastic Surgery and Burns Treatment, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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  • Michael Mørk Petersen
    Affiliations
    Department of Orthopedic Surgery, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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  • Werner Hettwer
    Affiliations
    Department of Orthopedic Surgery, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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  • Lisa Toft Jensen
    Affiliations
    Department of Plastic Surgery and Burns Treatment, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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  • Christian Torsten Bonde
    Affiliations
    Department of Plastic Surgery and Burns Treatment, Center of Head, Neck and Orthopedics, University Hospital of Copenhagen, Rigshospitalet, Inge Lehmannsvej 6, 2100 Copenhagen, Denmark
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Open AccessPublished:October 18, 2022DOI:https://doi.org/10.1016/j.bjps.2022.10.039

      Summary

      In patients with primary calcaneal malignancies, such as Ewing's sarcoma, radical treatment with amputation of the foot can result in serious functional impairment and chronic pain. Total calcanectomy followed by the reconstruction of the calcaneal defect offers an alternative treatment to amputation. Capanna et al. described a technique for successfully reconstructing long limb segmental bone defects using a free fibula flap placed within the intramedullary canal of an allograft.
      We present both a review of the literature on calcaneal reconstruction and describe how the principles of Capanna can be adapted to reconstruct the calcaneus.
      Total calcanectomy due to Ewing's sarcoma and the subsequent application of this novel reconstructive technique was performed in two young patients aged 5 and 16 years. The reconstruction was achieved by inserting a distally pedicled osteocutaneous fibula flap within the reamed canal of an allograft and placing the composite in the calcaneal defect. Reconstruction was successful with complete bone union between the allograft and the adjacent bone. There were no fractures or infections and both flaps survived. Functional outcome was assessed with a physiotherapist at a follow-up period of 2 years postoperatively, showing near-normal ambulance.
      This novel technique proved excellent as a limb salvage procedure, avoiding amputation, and offering a satisfactory oncological and functional outcome.

      Keywords

      Introduction

      Primary calcaneal malignancies are rare and account for less than 1% of primary bone tumors.

      Zeytoonjian T, Mankin HJ, Gebhardt MC, Hornicek FJ, Ph D. Distal lower extremity sarcomas: Frequency of occurrence and patient 2004:325–30.

      Amputation of the foot is often the preferred treatment as it is difficult to achieve wide surgical margins, and the reconstructive options for complex hindfoot defects are limited. Although no difference has been reported in patient survival, when comparing amputation and total calcanectomy as a limb salvage procedure for sarcomas, the prevalence of chronic pain related to amputation, and the potentially steep learning curve for ambulation with a prosthesis, favors limb salvage procedures as the preferred surgical treatment.
      • Choong PFM
      • Qureshi AA
      • Sim FH
      • Unni KK
      Osteosarcoma of the foot. A review of 52 patients at the Mayo Clinic.

      Ephraim PL, Wegener ST, Mackenzie EJ, Dillingham TR, Pezzin LE. Phantom pain, residual limb pain, and back pain in amputees: Results of a national survey 2005;86:1910–9. doi:10.1016/j.apmr.2005.03.031.

      • Geertzen JHB
      • Jutte P
      • Rompen C
      • Salvans M
      Calcanectomy, an alternative amputation? Two case reports.
      The calcaneus and overlying soft tissue play an important role in weight bearing, gait, and maintenance of the natural foot arches. Due to the indispensable role of the calcaneus in ambulation, total calcanectomy warrants appropriate reconstruction to achieve a satisfying functional outcome. Calcaneal defects after total calcanectomy have previously been reconstructed with calcaneal prostheses, bone allografts, regular pedicled fibula flaps, and free fibula flaps.

      Chou LB, Malawer MM. Osteosarcoma of the calcaneus treated with prosthetic replacement with twelve years of followup: A case report 2007:841–4. doi:10.3113/FAI.2006.0841.

      • Li J
      • Wang Z
      • Guo Z
      • Yang M
      • Chen G
      • Pei G
      Composite biological reconstruction following total calcanectomy of primary calcaneal tumors.
      • Jinfang C
      • Xuecheng C
      • Jin L
      • Baoguo S
      Heel Reconstruction.
      • Muscolo DL
      • Ayerza MA
      • Aponte-Tinao LA
      Long-term results of allograft replacement after total calcanectomy: A report of two cases.
      • Li J
      • Zheng W
      Surgical treatment of malignant tumors of the calcaneus.
      • Attinger C
      • Cooper P
      Soft tissue reconstruction for calcaneal fractures or osteomyelitis.
      • Imanishi J
      • Choong PFM
      Three-dimensional printed calcaneal prosthesis following total calcanectomy.
      Capanna et al. originally described a technique for the treatment of long limb segmental bone defects using a free fibula flap placed within the intramedullary canal of an allograft (Figure 1).
      • Capanna R
      • Bufalini C
      • Campanacci M
      A new technique for reconstructions of large metadiaphyseal bone defects.
      Incorporating a massive bone allograft in combination with a vascularized bone flap ensures both a malleable and adequate osseous bulk and a vascularization, which will enhance primary bone healing and reduce the risk of local infection.
      • Delloye C
      • Cornu O
      • Druez V
      • Barbier O
      Bone allografts. What they can offer and what they cannot.
      Figure 1
      Figure 1Demonstrates the basic idea behind our technique. The vascularized cortical bone of the fibula flap is fitted into the intramedullary canal of an allograft as a vascularized inlay.
      Figure 2
      Figure 2Provides an anatomical drawing of the osteotomized pedicled fibula flap, showing its flexibility obtained by the removal of the excess distal fibula bone.
      Figure 3
      Figure 3Intraoperative photographs in patient 1 show a) placing of the femoral head allograft into the hindfoot, b) the reamed canal in the femoral head allograft as well as the dissected vascular pedicle for the fibula flap, c) placing of the distally pedicled osteocutaneous fibula flap in the canal of the femoral head allograft, and d) four intraoperative photographs in patient 2 demonstrating oncological extirpation through a lateral approach with extensive debridement and following hindfoot defect.
      We present how the principles of Capanna can be adapted to reconstruct the calcaneus by using both a massive bone allograft and a distally pedicled osteocutaneous fibula flap as a limb salvage procedure, hereby avoiding amputation and providing a satisfactory oncological and functional outcome.

      Patients and methods

      Patients

      Two girls aged 5 years and 10 months (patient 1) and 16 years (patient 2) at the time of surgery both presented with a histopathologically verified Ewing's sarcoma of the calcaneus. The patients were diagnosed without any signs of metastatic disease and received both pre- and post-operative chemotherapy. A limb sparing total calcanectomy and succeeding reconstruction with a composite of an allograft and a vascularized distally pedicled osteocutaneous fibula graft was performed.

      Surgical technique

      Almost the same surgical procedure was performed in both patients. The preoperative planning was done incorporating handheld Doppler, Computer Tomography (CT), CT-angiography, and Magnetic Resonance Imaging (MRI). Extraosseous tumor component was assessed for resectability with attention to medial neurovascular invasion. A calcanectomy with wide surgical margins was performed using a lateral approach, including resection of the skin around the biopsy canal (patient 1 also had a medial biopsy scar removed). The calcaneus was located and extirpated with a brim of soft tissue (in patient 2 the most posterior part of calcaneus with insertion of the Achilles tendon was spared). The medially situated neurovascular bundle was unaffected and spared to preserve vascularization and innervation of the foot. A distally pedicled osteocutaneous fibula flap was raised. The skin paddle was outlined and dissected through a posterior approach preserving the cutaneous perforators. The fibula bone was then marked at proximal and distal sites for the planned osteotomy. The proximal ends of the peroneal vessels were ligated, and perfusion of the flap was hereby based on the distal vascular connections between the peroneal and anterior tibial vessels as well as the cutaneous perforators. The vessels and periosteum were rougined from the excess distal fibula bone, and the excess bone was removed, leaving a flexible vessel and periosteal bundle.
      In patient 1, part of an adult femoral head allograft from our local bone bank was fitted to replace the removed calcaneus. A calcaneal allograft from the Rizzoli Institute Cell and Musculoskeletal Tissue Bank (Bologna, Italy) was inserted into Patient 2. The allografts were canalized and fixed as an arthrodesis to the talus and cuboid bone using screws. In patient 2, the posterior part of the calcaneus was reattached to the allograft with a screw, while in patient 1 the Achilles tendon was fixated to the reconstructed heel using nonabsorbable sutures. The vascularized fibula bone was fitted into the allograft canal as a vascularized inlay and fixed using staples. (Figure 1, Figure 2, Figure 3, Figure 4)
      Figure 4
      Figure 4Postoperative X-rays that demonstrates the initial fixation of the allograft with vascularized fibula inlay to the talus and cuboid bone in a) patient 1 and b) patient 2.

      Results

      The patients were allowed weight bearing in an ankle brace when CT confirmed bone healing of the arthrodesis between calcaneus and talus (and for patient 2 between the calcaneus allograft and the posterior part of the patient´s own calcaneus with the Achilles tendon insertion) and incorporation of the fibula bone into the allograft at 3½ months (patient 1) and 6 months (patient 2). Full weight bearing without brace was allowed after 8 months in both cases when the arthrodesis between the allograft and talus had healed and showed complete bone union with substantial callus formation (Figure 5).
      Figure 5
      Figure 5Clinical photographs of the reconstructed hindfoot eight months postoperatively in a) patient 1 and b) patient 2. Corresponding X-rays shows solid healing of the arthrodesis between talus and calcaneus but no healing between calcaneus and the cuboid bone in c) patient 1, and healing of both arthrodeses and the attachment of the Achilles tendon in d) patient 2.
      There were no fractures or infections, but the second patient had delayed wound healing on the lateral aspect of the foot. Functional outcome was assessed at 2 years postoperative follow-up showing near-normal ambulance. The first patient had a slight in-toeing of the affected foot, while the second patient had normal gait. The slight in-toeing was assumed to be due to decreased eversion of the foot due to affection of the peroneal muscles.
      Patient 1 is now 10 years postoperatively undergoing bone elongation of the femur of approximately 3 cm due to a height reduction in the neocalcaneus and reduced longitudinal growth of the tibia. Patient 2 is 7 years postoperative with a fully functional lower extremity.

      Discussion

      Primary calcaneal malignancies, and especially Ewing's sarcoma of the calcaneus, are rare and, reports on limb sparing reconstructive options after oncological extirpation are scarce. Most studies on calcaneal reconstruction have been due to osteomyelitis or traumas.
      • Attinger C
      • Cooper P
      Soft tissue reconstruction for calcaneal fractures or osteomyelitis.
      ,
      • Lykoudis EG
      • Gantsos A
      • Dimou AO
      Complex calcaneal defect reconstruction with osteotomized free fibula-flexor hallucis longus osteomuscular flap.
      • Tuzun HY
      • Kurklu M
      • Kulahci Y
      • Turkkan S
      • Arsenishvili A
      Case report: Late reconstruction of the land mine–injured heel with an osteomyocutaneous composite fibular flap.
      • Barbour J
      • Saunders S
      • Hartsock L
      • Schimpf D
      • O'Neill P
      Calcaneal reconstruction with free fibular osteocutaneous flap.
      Reported reconstructive treatment options encompass bone allografts, calcaneal prostheses, regular pedicled fibula flaps, and free fibula flaps.

      Chou LB, Malawer MM. Osteosarcoma of the calcaneus treated with prosthetic replacement with twelve years of followup: A case report 2007:841–4. doi:10.3113/FAI.2006.0841.

      ,
      • Li J
      • Wang Z
      • Guo Z
      • Yang M
      • Chen G
      • Pei G
      Composite biological reconstruction following total calcanectomy of primary calcaneal tumors.
      ,
      • Attinger C
      • Cooper P
      Soft tissue reconstruction for calcaneal fractures or osteomyelitis.
      ,
      • Imanishi J
      • Choong PFM
      Three-dimensional printed calcaneal prosthesis following total calcanectomy.
      ,
      • Kurvin LA
      • Volkering C
      • Keßler SB
      Calcaneus replacement after total calcanectomy via vascularized pelvis bone.
      ,
      • Innocenti M
      • Lucattelli E
      • Daolio PA
      • Bastoni S
      • Marini E
      • Scoccianti G
      • et al.
      Calcaneal reconstruction after total calcanectomy with iliac crest free flap.
      Over the past decades, different microsurgical techniques have arisen for calcaneal and hindfoot reconstruction, and some authors have reported the use of free vascularized bone grafts as the fibula and iliac crest flaps with acceptable results.
      • Li J
      • Zheng W
      Surgical treatment of malignant tumors of the calcaneus.
      ,
      • Innocenti M
      • Lucattelli E
      • Daolio PA
      • Bastoni S
      • Marini E
      • Scoccianti G
      • et al.
      Calcaneal reconstruction after total calcanectomy with iliac crest free flap.
      Reconstruction of the heel is a complex procedure and should ideally aim at achieving the anatomical, biomechanical, and morphological properties of the natural heel.
      The fibula flap is a solid choice in calcaneal reconstruction as it provides strong and linear cortical bone with the prospect of progressive bone hypertrophy in response to increased weight loading.
      • Jinfang C
      • Xuecheng C
      • Jin L
      • Baoguo S
      Heel Reconstruction.
      ,
      • Lykoudis EG
      • Gantsos A
      • Dimou AO
      Complex calcaneal defect reconstruction with osteotomized free fibula-flexor hallucis longus osteomuscular flap.
      ,
      • Tuzun HY
      • Kurklu M
      • Kulahci Y
      • Turkkan S
      • Arsenishvili A
      Case report: Late reconstruction of the land mine–injured heel with an osteomyocutaneous composite fibular flap.
      ,
      • Mei J
      • Wu S
      • Yang Z
      • Lui KW
      • Ye W
      • Tang M
      Functional total heel reconstruction with a fibular osteomyocutaneous flap.
      ,
      • Beris AE
      • Lykissas MG
      • Korompilias AV
      • Vekris MD
      • Mitsionis GI
      • Malizos KN
      • et al.
      Vascularized fibula transfer for lower limb reconstruction.
      It thereby enables the reconstructed heel to withstand increasing loads and also allows for the reconstruction of surrounding soft tissue.
      • Beris AE
      • Lykissas MG
      • Korompilias AV
      • Vekris MD
      • Mitsionis GI
      • Malizos KN
      • et al.
      Vascularized fibula transfer for lower limb reconstruction.
      ,
      • Lin CH
      • Wei FC
      • Chen HC
      • Chuang DCC
      Outcome comparison in traumatic lower-extremity reconstruction by using various composite vascularized bone transplantation.
      The pedicled and free fibula flaps have in various studies been reported as successful options in limb salvage surgery for calcaneal malignancies, osteomyelitis, or trauma.
      • Lykoudis EG
      • Gantsos A
      • Dimou AO
      Complex calcaneal defect reconstruction with osteotomized free fibula-flexor hallucis longus osteomuscular flap.
      • Tuzun HY
      • Kurklu M
      • Kulahci Y
      • Turkkan S
      • Arsenishvili A
      Case report: Late reconstruction of the land mine–injured heel with an osteomyocutaneous composite fibular flap.
      • Barbour J
      • Saunders S
      • Hartsock L
      • Schimpf D
      • O'Neill P
      Calcaneal reconstruction with free fibular osteocutaneous flap.
      ,
      • Li J
      • Guo Z
      • Pei GX
      • Wang Z
      • Chen GJ
      • Wu ZG
      Limb salvage surgery for calcaneal malignancy.
      Lin et al. found that fibular flaps have less donor-site morbidity, less recipient-site morbidity, better survival rates, and better functional results than other flaps in post-traumatic reconstruction of the heel.
      • Lin CH
      • Wei FC
      • Chen HC
      • Chuang DCC
      Outcome comparison in traumatic lower-extremity reconstruction by using various composite vascularized bone transplantation.
      Using a distally pedicled fibula flap incorporated in a massive bone allograft, as in this study, has several benefits.
      Vascularized bone flaps as the pedicled and free fibula flaps may increase resistance to infection, enhance primary bone healing, and tolerate mechanical stress better due to their superior circulation compared to regular bone allografts.
      A crucial determinant of the success of the distally pedicled fibula flap is therefore the integrity of the vascular connections between the peroneal and anterior tibial arteries.
      A bone allograft provides a natural osteoconductive material that serves as a structural spacer, which can support migrating host cells and result in progressive bone union with the adjacent bone.
      • Delloye C
      • Cornu O
      • Druez V
      • Barbier O
      Bone allografts. What they can offer and what they cannot.
      Incorporating a vascularized flap into a massive bone allograft therefore attains the benefits from both structures. The allograft provides a shapeable and strong osseous bulk that will increase the likelihood of early mobilization and, collectively with the vascularized pedicled fibula flap, increase long-term weight bearing capability.
      This study reports to the best of our knowledge, the first applications of the adapted Capanna technique in calcaneal reconstruction.
      This novel technique of inserting a distally pedicled osteocutaneous fibula flap into the reamed canal of a massive bone allograft proved to be an excellent reconstructive option for calcaneal defects after total calcanectomy due to primary calcaneal malignancy. The adapted Capanna technique achieved successful limb salvage of the foot, offering both a satisfactory oncological and functional outcome. This technique could also prove beneficial as a reconstructive option for calcaneal defects arising due to trauma or osteomyelitis.

      Author contributions

      Nizar Hamrouni: Wrote and edited the manuscript, reviewed the literature; Jens Hjermind Højvig: Reviewed and edited the manuscript; Michael Mørk Petersen: Operated on patients, reviewed the manuscript, and planned the study concept; Werner Hettwer: Operated on patients, reviewed the manuscript, and planned the study concept; Lisa Toft Jensen: Operated on patients, reviewed the manuscript, and planned the study concept; Christian Torsten Bonde: Operated on patients, wrote part of the manuscript, reviewed and edited the manuscript, and planned the study concept.

      Funding

      None.

      Conflict of Interest

      The authors have nothing to disclose.

      Ethical approval statement

      No ethical approval was needed for this study

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