Long-Term Follow-Up of Biological Reconstruction with Free Fibular Graft after Resection of Extremity Diaphyseal Bone Tumors

Effect of Plate Configuration in the Primary Stability of Osteotomies and Biological Reconstructions of Femoral Defects: Finite-Element Study

BACKGROUND/OBJECTIVE

Osteosynthesis is an alternative treatment for stabilizing femur-bone traumas. The initial stability of the fixation systems is one of the biomechanical parameters affecting implant failure and bone union, especially in surgeries of intercalary reconstructions after the removal of bone tumors. This study aimed to investigate the initial biomechanical effect of using one or two osteosynthesis plate configurations for femoral fixation and the effect of fastening the allograft to the osteosynthesis plate in the case of femoral allograft reconstructions.

METHODS

Three finite-element models of a femur with three different fixation conditions for a transverse osteotomy in the middle of the diaphysis, i.e., using one and two osteosynthesis plates and an intercalary allograft, were constructed. An eight-hole compression plate and a six-hole second plate were used to simulate osteosynthesis plates. The plate screws were tightened previously to the loading, and the tightening sequences simulate the bolt-tightening procedure in a surgical environment. The models were imported into the ADINA System for nonlinear analysis, using compression loads applied over the femur head.

RESULTS

Models with the dual fixation systems had the most outstanding compression stiffness. The femur head movement in the dual plate system was 24.8% smaller than in the single plate system. A statistical analysis of a region of interest (VOI) placed in the femur diaphysis showed that the biomechanical effect of using the dual plate system is smaller in the osteotomy region than at the femur head, e.g., a displacement average decrease of only 5% between the two systems, while the maximum value decreases by 26.8%. The allograft fixation to the second osteosynthesis plate leads to an improvement in the system stability.

CONCLUSIONS

The results presented in this work show that including the bolt analysis in the femoral diaphysis osteotomy fixation will allow for capturing the nonlinear behavior of the osteotomy region more realistically. The stability of the intercalary reconstruction of the femoral diaphysis was higher when the allograft was fastened to the second osteosynthesis plate.

Intercalary Resection of the Tibia for Primary Bone Tumors: Are Vascularized Fibula Autografts With or Without Allografts a Durable Reconstruction?

BACKGROUND

Reconstruction with vascularized fibula grafts (VFG) after intercalary resection of sarcoma may offer longevity by providing early graft-host union and fracture healing. The ability of the fibula to hypertrophy under mechanical stress, as well as vascularized bone in the area, may also be advantageous, given that soft tissues may be compromised because of resection, chemotherapy, or radiation therapy. VFG with a massive allograft combines the primary mechanical stability of the graft with the biological potential of the vascularized fibula; however, complications and the durability of this combined reconstruction are not well described.

QUESTIONS/PURPOSES

(1) What was the proportion of complications after reconstruction with VFG, with or without allografts? (2) What was the functional result after surgical treatment as assessed by the Musculoskeletal Tumor Society (MSTS) score? (3) What was the survivorship of these grafts free from revision and graft removal?

METHODS

Between 1988 and 2021, 219 patients were treated at our institution for a primary malignant or aggressive benign bone tumor of the tibia with en bloc resection. Of those, 54% (119 of 219) had proximal tibial tumors with epiphyseal involvement and were treated with either intra-articular resection and reconstruction with an osteoarticular allograft, allograft-prosthesis composite (APC), or modular prosthesis according to age, diagnosis, and preoperative or postoperative radiotherapy. Nine percent (20) of patients had distal tibial tumors that were treated with intra-articular resection and reconstruction with ankle arthrodesis using allogenic or autologous grafts, and 0.5% (1 patient) underwent total tibial resection for extensive tumoral involvement of the tibia and reconstruction with an APC. Thirty-six percent (79) of patients had a metadiaphyseal bone tumor of the tibia and were treated with intercalary joint-sparing resection. We routinely use reconstruction with VFG after intercalary tibial resection for primary malignant or aggressive benign bone tumors in patients with long life expectancy and high functional demands and in whom at least 1 cm of residual bone stock of the proximal or distal epiphysis can be preserved. By contrast, we routinely use intercalary massive allograft reconstruction in short resections or in patients with metastatic disease who do not have long life expectancy. We avoid VFG in patients with tibial bone metastasis, patients older than 70 years, or primary bone tumors in patients who may undergo postoperative radiotherapy; in these patients, we use alternative reconstructive methods such as intercalary prostheses, plate and cement, or intramedullary nailing with cement augmentation. According to the above-mentioned indications, 6% (5 of 79) of patients underwent massive allograft reconstruction because they were young and had intercalary resections shorter than 7 cm or had metastatic disease at diagnosis without long life expectancy, whereas 94% (74) of patients underwent VFG reconstruction. The median age at operation was 16 years (range 5 to 68 years). The diagnosis was high-grade osteosarcoma in 22 patients, Ewing sarcoma in 19, adamantinoma in 16, low-grade osteosarcoma in five, fibrosarcoma in three, malignant fibrous histiocytoma and Grade 2 chondrosarcoma in two, and malignant myoepitelioma, angiosarcoma of bone, malignant peripheral nerve sheath tumor of bone, squamous cell carcinoma secondary to chronic osteomyelitis, and desmoplastic fibroma in one patient each. Median follow-up was 12.3 years (range 2 to 35 years). The median tibial resection length was 15 cm (range 7 to 27 cm), and the median fibular resection length was 18 cm (range 10 to 29 cm). VFG was used with a massive allograft in 55 patients, alone in 12 patients, and combined with allogenic cortical bone struts in seven patients. We used VFG combined with a massive allograft in patients undergoing juxta-articular, joint-sparing resections that left less than 3 cm of residual epiphyseal bone, for intra-epiphyseal resections, or for long intercalary resections wherein the allograft can provide better mechanical stability. In these clinical situations, the combination of a VFG and massive allograft allows more stable fixation and better tendinous reattachment of the patellar tendon. VFG was used with cortical bone struts in distal tibia intercalary resections where the narrow diameter of the allograft did not allow concentric assembling with the fibula. Finally, VFG alone was often used after mid- or distal tibia intercalary resection in patients with critical soft tissue conditions because of previous surgery, in whom the combination with massive allograft would result in a bulkier reconstruction. We ascertained complications and MSTS scores by chart review, and survivorship free from revision and graft removal was calculated using the Kaplan-Meier estimator. In our study, however, the occurrence of death as a competing event was observed in a relatively low proportion of patients, and only occurred after the primary event of interest had already occurred. Considering the nature of our data, we did not consider death after the primary event of interest as a competing event.

RESULTS

In all, 49% (36 of 74) of patients experienced complications and underwent operative treatment. There were 45 complications in 36 patients. There was one instance of footdrop secondary to common peroneal nerve palsy, four wound problems, one acute vein thrombosis of the VFG pedicle and one necrosis of the skin island, two episodes of implant-related pain, 10 nonunions, six fractures, six deep infections, nine local recurrences, one Achilles tendon retraction, one varus deformity of the proximal tibia with postoperative tibial apophysis detachment, one knee osteoarthritis, and one hypometria. The median MSTS score was 30 (range 23 to 30); the MSTS score was assessed only in patients in whom the VFG was retained at the final clinical visit, although if we had considered those who had an amputation, the overall score would be lower. Revision-free survival of the reconstructions was 58% (95% confidence interval 47% to 70%) at 5 years, 52% (95% CI 41% to 65%) at 10 and 15 years, and 49% (95% CI 38% to 63%) at 20 and 30 years. Eight patients underwent VFG removal because of complications, with an overall reconstruction survival of 91% (95% CI 84% to 98%) at 5 years and 89% (95% CI 82% to 97%) at 10 to 30 years.

CONCLUSION

VFG, alone or combined with an allograft, could be considered in reconstructing a lower extremity after intercalary resections of the tibia for primary bone tumors, and it avoids the use of a large endoprosthesis. However, this procedure was associated with frequent, often severe complications during the first postoperative years and complication-free survival of 58% at 5 years. Nearly 10% of patients ultimately had an amputation. For patients whose reconstruction succeeded, the technique provides a durable reconstruction with good MSTS scores, and we believe it is useful for active patients with long life expectancy. Fractures, frequently observed in the first 5 years postoperatively, might be reduced using long-spanning plate fixation, and that appeared to be the case in our study. Nonbridging fixation can be an option in intraepiphyseal resection when a spanning plate cannot be used or in pediatric patients to enhance fibula hypertrophy and remodeling. We did not directly compare VFG with or without allografts to other reconstruction options, so the decision to use this approach should be made thoughtfully and only after considering the potential serious risks.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

First-ever ankle arthrodesis with the Capanna technique in an infected open fracture

Although bone transport by means of distraction osteogenesis has become the standard of care for massive segmental bone defects, the technique faces limitations such as the lengthy period of time during which patients must wear an external fixator. Thus, other techniques may be more appropriate in certain circumstances. Capanna developed a combination of vascularized fibular grafts and strut allografts in a way that the strut allograft provides with significant initial mechanical stability, which facilitates incorporation of a vascularized fibular graft and promotes long-term survival of the reconstruction. The case presented in this report is the first in the medical literature where a circular external fixator is used as a stabilization method in a patient with a structural bone deficiency treated by means of the Capanna technique. It is also one of the few reported cases where the underlying condition does not originate in a tumor and where the joint is involved.

Inactivation and replantation of the knee joint: an infeasible surgical method

BACKGROUND

The inactivation and replantation of autologous tumor bones are important surgical methods for limb salvage in patients with malignancies. Currently, there are few reports on the inactivation and replantation of the knee joint. In this study, we aimed to evaluate the feasibility of our surgical approach.

METHODS

This is a retrospective case series study. We retrospectively collected the clinical data of patients with sarcoma treated with knee joint inactivation and replantation and analyzed the efficacy of this surgical method. The bone healing and complications in these patients after inactivated autograft replantation were assessed.

RESULTS

This study included 16 patients. Fifteen patients had osteosarcoma, and one had Ewing's sarcoma. The average length of the inactivated bone is 20.2 cm (range 13.5-25.3 cm). All the patients underwent internal plate fixation. The average follow-up duration was 30 months (range 8-60 months). Before the data deadline of this study, eight (50%) patients were still alive, and eight (50%) died of sarcoma metastasis. Eight (50%) patients achieved bone healing at the diaphysis site of the inactivated tumor bone, with an average bone healing time of 21.9 months (range, 12-36 months). Five (31%) patients died due to metastases and did not achieve bone healing. Two (12.5%) patients did not achieve bone healing because of infection, and one (6.3%) patient underwent amputation due to tumor recurrence. Ten (62.5%) patients experienced fractures around the joint ends of the inactivated replanted bone, and eight of these ten patients were combined with joint dislocation.

CONCLUSION

The incidence of joint deformities after the knee-joint inactivation and replantation is extremely high and is not recommended for use.

Treatment of a case of septic tibial nonunion by the Capanna technique

This report presents the case of a 25-year-old male with an infected tibial diaphyseal nonunion caused by a bone transport procedure carried out to treat an open fracture the patient had sustained 10 years before referral to our hospital. After an initial radical debridement, a bone defect was created, which was subsequently obliterated by placement of an antibiotic-impregnated cement spacer and Stimulan beads and covered by an anterolateral thigh flap. As the patient refused to wear an external fixator and his osseous biology was not amenable to a Masquelet procedure, a decision was made to apply the Capanna technique as soon as the infection healed. The second debridement resulted in a 12-cm-long bone defect that was filled with a tibial allograft and a vascularized fibular graft. At six months, the patient had regained full knee function and was able to bear his full weight, without pain or the need of support equipment. At one year, the bone had healed completely, the infection had subsided and the patient was able to resume his everyday activities. Although the Capanna technique was initially developed to reinforce reconstructions at risk of fracture or nonunion as a result of chemotherapy, its use in post-traumatic cases has been shown to be successful in a selected group of patents. Our study demonstrated that increasing the stability of a reconstruction with an allograft can accelerate the time to heal, and that using a vascularized fibular graft can enhance incorporation of the whole construct. It can be concluded that the Capanna technique is a valid treatment option for managing infected segmental bone defects in selected patients.