Free vascularized fibular graft salvage of complications of long-bone allograft after tumor reconstruction

Comparative analysis of free vascularized fibula grafting and Ilizarov bone transport in management of segmental long bone defect of the lower limb: A systematic review and meta-analysis

Introduction

Reconstruction of segmental defects of long bones is a daunting task for surgeons. Bone transport with the help of Illizarov external fixator and vascularized free fibula flap are some of the most discussed and valid options for the same. Both techniques have their limitations and overlapping indications. However, there has been no objective evidence in the manner of a systematic review supporting one treatment method over the other.

Aim

This systemic review is aimed to compare the bony union, functional outcomes, and complications of Illizarov bone lengthening and free fibula flap performed for segmental bone defects of long bones of the leg.

Methods

A comprehensive search was done for all studies published before May 2023. Any observational study comparing bone transport based on Illizarov external fixator and free vascularized fibula grafting techniques for treating lower limb long bone segmental defects was entailed in this study.

Results

This systematic review comprised of five retrospective studies. A total of 96 patients were treated by the Illizarov-based bone transport technique and 72 patients were treated by the free vascularized fibula grafting technique. The free vascularized fibula grafting technique yielded a shorter mean time to union (average difference 9.3 months), relatively shorter external fixator time (average difference 5.32 months), and external fixator index (average difference 0.57 months/cm). However, there was no difference in terms of bony and functional outcomes between both techniques when used for the reconstruction of bony defects in the lower limb. Total number of complications was 68 % higher in bone transport with Illizarov external fixator. However, the rates of non-union didn't differ between the groups.

Conclusion

The free vascularized fibula grafting technique had a lesser time to bony union, shorter time for external fixator application, and lower incidence of complications. However, the functional and bony outcomes didn't differ between both techniques.

Level of evidence

Level 4.

Free iliac crest grafting technology for the management of critical-sized tibial bone defect

OBJECTIVE

To introduce the method and experience of treating critical-sized tibial bone defect by taking large iliac crest bone graft.

METHODS

From January 2020 to January 2022, iliac crest bone grafting was performed in 20 patients (10 men and 10 women) with critical-sized tibial bone defect. The mean length of bone defect was 13.59 ± 3.41. Bilateral iliac crest grafts were harvested, including the inner and outer plates of the iliac crest and iliac spine. The cortical bone screw was used to integrate two iliac bone blocks into one complex. Locking plate was used to fix the graft-host complex, supplemented with reconstruction plate to increase stability when necessary. Bone healing was evaluated by cortical bone fusion on radiographs at follow-up, iliac pain was assessed by VAS score, and lower limb function was assessed by ODI score. Complications were also taken into consideration.

RESULTS

The average follow-up time was 27.4 ± 5.6 (Range 24-33 months), the mean VAS score was 8.8 ± 1.9, the mean ODI score was 11.1 ± 1.8, and the number of cortical bone fusion in the bone graft area was 3.5 ± 0.5. Satisfactory fusion was obtained in all cases of iliac bone transplant-host site. No nonunion, shift or fracture was found in all cases. No infection and bone resorption were observed that need secondary surgery. One patient had dorsiflexion weakness of the great toe. Hypoesthesia of the dorsal foot was observed in 2 patients. Ankle stiffness and edema occurred in 3 patients. Complications were significantly improved by physical therapy and rehabilitation training.

CONCLUSION

For the cases of critical-sized tibial bone defect, the treatment methods are various. In this paper, we have obtained satisfactory results by using large iliac bone graft to treat bone defect. This approach can not only restore the integrity of the tibia, but also obtain good stability with internal fixation, and operation skills are more acceptable for surgeons. Therefore, it provides an alternative surgical method for clinicians.

Comparing Fibula Flap Insetting Techniques for Pediatric Oncologic Extremity Reconstruction

BACKGROUND

Extremity reconstruction in skeletally immature patients presents unique challenges in terms of operative technique, bone healing, and limb function. A variety of insetting techniques have been described, with no clearly superior option. The authors hypothesized that vascularized fibula flaps placed in the intramedullary space are associated with shorter union times and better functionality compared with onlay flaps.

METHODS

In a cohort study, the authors retrospectively reviewed the medical records of all pediatric patients who underwent fibula flap extremity reconstruction at a single center from 2001 through 2018. Comorbidities, complications, and outcomes were analyzed. Complete fibula union was based on radiographic evidence of significant cortical bridging.

RESULTS

Thirty-three patients (mean age, 13.6 years; range, 2 to 18 years) underwent pedicled ( n = 7) or free ( n = 26) fibula flap reconstructions in 12 upper extremities and 21 lower extremities. Median follow-up was 69.5 months (interquartile range, 16.3 to 114.6 months). Onlay and intramedullary fibula position compared with intercalary placement (median, 13.5 and 14.6 months versus 3.4 months; P = 0.002) were associated with longer time to complete bone union. Complications including allograft fracture ( P = 0.02) and hardware removal ( P = 0.018) were also associated with longer time to complete union and eventual conversion to megaprosthesis ( P = 0.02, P = 0.038). Thirty-two patients (97%) achieved full union and a functional reconstruction.

CONCLUSIONS

Fibula flap reconstruction is safe and effective for pediatric long-bone reconstruction. Longer fibula union times were associated with onlay and intramedullary fibula placement, allograft fracture, and hardware removal.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Non-vascularised corticocancellous (tricortical) iliac bone graft longer than 3 cm for non-union after failed surgical treatment

PURPOSE

We hypothesised that traditional iliac tricortical bone grafts (no vascularised) still have a reasonable role in promoting satisfactory bony healing in non-union defects of certain sizes. Here, we report the clinical/radiological outcomes through a retrospective case series.

METHODS

We screened 74 patients with definitive non-union in the long bones of the upper extremities who visited the outpatient department from 2008 to 2018. Among these patients, 25 who met our inclusion/exclusion criteria were investigated.

RESULTS

The mean age was 51.92 years, and there were 12, 9, 1, and 3 lesions of the radius, ulna, clavicle, and humerus, respectively. The tools for primary fixations were plate and intramedullary nails in 24 and 1 patients, respectively. Six patients presented with atrophic non-union. The mean period from a previous surgery was 6.84 months. The mean defective bone sizes were 1.81 and 3.50 cm pre-debridement and post-debridement, respectively. All devices had locking plates longer than the previous plate, and the graft was concurrently fixed by screws in three patients. At a mean of 15.92 weeks after the revision surgery, all patients experienced union. At the final follow-up, the clinical outcomes were satisfactory. No significant differences in clinical outcomes were found according to the lesion, type of non-union, period from the previous surgery, or harvest length of the iliac bone.

CONCLUSIONS

If the proper indications and some technical aspects are considered, a non-vascularised iliac bone graft longer than 3 cm could still be a reasonable option for treating diaphyseal non-union of the upper extremities.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Docking site complications analysis of Ilizarov bone transport technique in the treatment of tibial bone defects

BACKGROUND

Treating long bone defects of the extremities caused by trauma, infection, tumours, and nonunion has been challenging for clinical orthopaedic surgeons. Bone transport techniques have the potential to treat bone defects. However, inevitable docking site complications related to bone transport techniques have been reported in many studies. The purpose of this study was to investigate the risk factors associated with docking site complications in patients who underwent the Ilizarov bone transport technique for the treatment of tibial bone defects.

METHODS

This retrospective study included 103 patients who underwent bone transport for the treatment of large bone defects in the tibia from October 2012 to October 2019. Patient demographic data, complications and clinical outcomes after a minimum of 2 years of follow-up were collected and retrospectively analysed. Additionally, univariate analysis and logistic regression analysis were used to analyse the factors that may affect the development of docking site complications in patients with tibial bone defects treated with the Ilizarov bone transport technique. The clinical outcomes were evaluated using the Association for the Study and Application of the Ilizarov criteria (ASAMI) at the last clinical follow-up.

RESULTS

All 103 patients with an average follow-up of 27.5 months. The docking site complications rate per patient was 0.53, and delayed union occurred in 22 cases (21.4%), axial deviation occurred in 19 cases (18.4%) and soft tissue incarceration occurred in 10 cases (9.7%). According to the results of the logistic regression analysis, the bone defect length (P = 0.001, OR = 1.976), and bone defect of distal 1/3 (P = 0.01, OR = 1.976) were significantly correlated with delayed union. Bone defect length (P < 0.001, OR = 1.981) and external fixation time (P = 0.012, OR = 1.017) were significantly correlated with axial deviation. Soft tissue defects (P = 0.047, OR = 6.766) and the number of previous operations (P = 0.001, OR = 2.920) were significantly correlated with soft tissue incarceration. The ASAMI bone score at the last follow-up showed a rate of excellent and good bone results of 95.1% and a rate of excellent functional results of 90.3%.

CONCLUSION

The Ilizarov bone transport technique is a practical and effective method for the treatment of tibial bone defects. However, the incidence of complications at the docking site is high, of which bone defect length, external fixation time, the number of previous operations, soft tissue defects and the bone defect of distal 1/3 are statistically significantly associated with the occurrence of docking site complications.

Ilizarov technique in the treatment of bone defects of the radius and ulna: a systematic review and meta-analysis

PURPOSE

The objective of this systematic review and meta-analysis was to assess the efficacy of the Ilizarov method in the treatment of radius and ulna bone defects.

METHODS

The PubMed, Embase, Web of Science, Cochrane Library, Ovid MEDLINE, and Scopus databases were searched for articles published up to May 2023. The quality of the studies was evaluated using a modified version of the Newcastle-Ottawa scale. The effect size and confidence intervals at 95% for the main results were calculated. The heterogeneity was evaluated. The demographic data, defect size (DS), external fixation time (EFT), external fixation index (EFI), and complications were extracted and analyzed using the Stata version 16.

RESULTS

This meta-analysis identified and included seven studies involving 98 patients. The union rate of 100% was reported in all studies. According to the findings of the single-arm meta-analysis, the pooled DS was 3.42 cm (95% CI [2.64, 4.21], I2 = 53.5%, P = 0.045), EFT was 148.43 days (95% CI [97.49, 199.38], I2 = 91.9%, P = 0.000), and EFI was 41.32 days/cm (95% CI [35.72, 46.91], I2 = 62.2%, P = 0.021). Pin tract infection was the most common complication, as reported in six studies.

CONCLUSION

The findings of the present meta-analysis indicate that the Ilizarov technique is a successful treatment option for bone defects in the radius and ulna. This method has demonstrated efficacy in achieving expected clinical outcomes.

Treatment of Critical-Sized Bone Defects Involving the Ankle Joints: Staged Tibiotalocalcaneal Arthrodesis With Induced Membrane Technique and Intramedullary Nail

OBJECTIVES

To report the outcomes of staged tibiotalocalcaneal (TTC) arthrodesis for critical-sized bone defects involving the ankle joints.

DESIGN

Retrospective review of case series.

SETTING

Two academic Level 1 trauma centers.

PATIENTS/PARTICIPANTS

The study included 20 patients with critical-sized (≥2 cm) segmental bone defects around the ankle joints.

INTERVENTION

Staged TTC arthrodesis was performed with induced membrane technique and retrograde intramedullary nail.

MAIN OUTCOME MEASUREMENTS

We investigated the radiological evaluation, including modified radiographic union scale for tibia fractures score, time to union, and leg length discrepancy, and functional outcomes using foot and ankle outcome score and American Orthopaedic Foot and Ankle Society ankle-hindfoot score.

RESULTS

The average bone defect was 6.4 cm (range: 2.4-12.3). Two of the 20 (10%) patients developed recurrence of infection. Fifteen patients (75%) achieved primary healing. Three patients (15%) were treated with repeated bone grafting and additional plating. The average time to union and leg length discrepancy were 10 months (range: 5-21) and 9 mm (range: 0-31), respectively. The mean foot and ankle outcome score and American Orthopaedic Foot and Ankle Society ankle-hindfoot score were 63 (range: 52-71) and 74 (range: 64-81), respectively.

CONCLUSIONS

Staged TTC arthrodesis with induced membrane technique and intramedullary nail can be an effective treatment method for critical-sized bone defects involving the ankle joints.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Bone Defects in Tibia Managed by the Bifocal vs. Trifocal Bone Transport Technique: A Retrospective Comparative Study

Background

The purpose of this study is to evaluate the clinical effectiveness and determine the differences, if any, between the trifocal bone transport (TFT) technique and the bifocal bone transport (BFT) technique in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator.

Methods

A total of 53 consecutive patients with long segmental tibial bone defects caused by infection and treated by monolateral rail external fixator in our department were retrospectively collected and analyzed from the period January 2013 to April 2019, including 39 males and 14 females with an average age of 38.8 ± 12.4 years (range 19–65 years). Out of these, 32 patients were treated by the BFT technique, and the remaining 21 patients were managed by the TFT technique. The demographic data, operation duration (OD), docking time (DT), external fixation time (EFT), and external fixation index (EFI) were documented and analyzed. Difficulties that occur during the treatment were classified according to Paley. The clinical outcomes were evaluated by following the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria at the last clinical visit.

Results

All patients achieved an infection-free union finally, and there was no significant difference between the two groups in terms of demographic data and both ASAMI bone and functional scores (p > 0.05). The mean defect size and OD in TFT (9.4 ± 1.5 cm, 161.9 ± 8.9 min) were larger than that in BFT (7.8 ± 1.8 cm, 122.5 ± 11.2 min) (p < 0.05). The mean DT, EFT, and EFI in TFT (65.9 ± 10.8 days, 328.0 ± 57.2 days, 34.8 ± 2.1 days/cm) were all less than those in BFT (96.8 ± 22.6 days, 474.5 ± 103.2 days, 60.8 ± 1.9 days/cm) (p < 0.05). Difficulties and complications were more prevalent in the BFT group than in the TFT group (p < 0.05).

Conclusion

Both the trifocal and BFT techniques achieve satisfactory clinical outcomes in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator. The TFT technique can significantly decrease the DT, EFT, EFI, difficulties, and complications compared with the BFT technique.

Supine harvest of vascularised scapular bone grafts-Anatomical study and clinical application

BACKGROUND

We report our findings from an anatomical study on harvest of a vascularized scapular bone graft from a supine position. A clinical case is presented to illustrate the operative approach.

METHODS

Twenty cadaveric hemibody specimens were dissected in the supine position. Outcomes of interest included the characterization of anatomical variants and measurements of pedicle length. Specific measurements included distance from the origin of the subscapular artery (at the axillary artery) to the branch point of the angular artery from the thoracodorsal artery or serratus branch and the length of the angular branch proper.

RESULTS

There are five reported anatomic variations regarding the origin of the angular branch of the thoracodorsal artery. In our cadaveric cohort only four known types were seen, and an entirely new variant was encountered. Six cadaveric dissections exhibited a type 3 configuration, six were type 1, four were type 2, three were type 4, and one was a previously unreported variant we termed a type 6, with multiple angular artery branches originating from the posterior branch of the thoracodorsal. The mean distance between the origin of the subscapular artery and the takeoff of the angular branch was 6.3 ± 2.0 cm. The mean length of the angular branch was 3.7 ± 1.4 cm.

CONCLUSIONS

Supine positioning for harvest of a vascularized bone graft obviates the need for an intraoperative position change and allows reconstruction of bone defects in the hand and upper extremity within a single surgical field.

Technique and results after immediate orthotopic replantation of extracorporeally irradiated tumor bone autografts with and without fibular augmentation in extremity tumors

Background

Reconstruction of the skeletal defects resulting from the resection of bone tumors remains a considerable challenge and one of the possibilities is the orthotopic replantation of the irradiated bone autograft. One technical option with this technique is the addition of a vital autologous fibular graft, with or without microvascular anastomosis. The aim of our study was to evaluate the clinical results of the treatment of our patient cohort with a specific view to the role of fibular augmentation.

Methods

Twenty-one patients with 22 reconstructions were included. In all cases, the bone tumor was resected with wide margins and in 21 of them irradiated with 300 Gy. In the first case, thermal sterilization in an autoclave was used. The autograft was orthotopically replanted and stabilized with plates and screws. Fifteen patients underwent an additional fibular augmentation, 8 of which received microvascular anastomoses or, alternatively, a locally pedicled fibular interposition.

Results

the most common diagnosis was a Ewing sarcoma (8 cases) and the most common location was the femur (12 cases). The mean follow-up time was 70 months (16–154 months). For our statistical analysis, the one case with autoclave sterilization and 3 patients with tumors in small bones were excluded. During follow-up of 18 cases, 55.6% of patients underwent an average of 1.56 revision surgeries. Complete bony integration of the irradiated autografts was achieved in 88.9% of cases after 13.6 months on average. In those cases with successful reintegration, the autograft was shorter (n.s.). Microvascular anastomosis in vascularized fibular strut grafts did not significantly influence the rate of pseudarthrosis.

Conclusions

the replantation of extracorporeally irradiated bone autografts is an established method for the reconstruction of bone defects after tumor resection. Our rate of complications is comparable to those of other studies and with other methods of bone reconstruction (e.g. prosthesis). In our opinion, this method is especially well suited for younger patients with extraarticular bone tumors that allow for joint preservation. However, these patients should be ready to accept longer treatment periods.

Is three-dimensional-printed custom-made ultra-short stem with a porous structure an acceptable reconstructive alternative in peri-knee metaphysis for the tumorous bone defect?

Background

Long-lasting reconstruction after extensive resection involving peri-knee metaphysis is a challenging problem in orthopedic oncology. Various reconstruction methods have been proposed, but they are characterized by a high complication rate. The purposes of this study were to (1) assess osseointegration at the bone implant interface and correlated incidence of aseptic loosening; (2) identify complications including infection, endoprosthesis fracture, periprosthetic fracture, leg length discrepancy, and wound healing problem in this case series; and (3) evaluate the short-term function of the patient who received this personalized reconstruction system.

Methods

Between September 2016 and June 2018, our center treated 15 patients with malignancies arising in the femur or tibia shaft using endoprosthesis with a 3D-printed custom-made stem. Osseointegration and aseptic loosening were assessed with digital tomosynthesis. Complications were recorded by reviewing the patients’ records. The function was evaluated with the 1993 version of the Musculoskeletal Tumor Society (MSTS-93) score at a median of 42 (range, 34 to 54) months after reconstruction.

Results

One patient who experienced early aseptic loosening was managed with immobilization and bisphosphonates infusion. All implants were well osseointegrated at the final follow-up examination. There are two periprosthetic fractures intraoperatively. The wire was applied to assist fixation, and the fracture healed at the latest follow-up. Two patients experienced significant leg length discrepancies. The median MSTS-93 score was 26 (range, 23 to 30).

Conclusions

A 3D-printed custom-made ultra-short stem with a porous structure provides acceptable early outcomes in patients who received peri-knee metaphyseal reconstruction. With detailed preoperative design and precise intraoperative techniques, the reasonable initial stability benefits osseointegration to osteoconductive porous titanium, and therefore ensures short- and possibly long-term durability. Personalized adaptive endoprosthesis, careful intraoperative operation, and strict follow-up management enable effective prevention and treatment of complications. The functional results in our series were acceptable thanks to reliable fixation in the bone-endoprosthesis interface and an individualized rehabilitation program. These positive results indicate this device series can be a feasible alternative for critical bone defect reconstruction. Nevertheless, longer follow-up is required to determine whether this technique is superior to other forms of fixation.

Is the Capanna Technique a Reliable Method for Revision Surgery after Failure of Previous Limb-Salvage Surgery?

BACKGROUND

Reconstruction of a massive bone defect caused by previous failed limb-salvage surgery in patients with bone sarcoma is challenging. Many procedures have been used, but they all have their inherent disadvantages. The Capanna technique has demonstrated good functional outcomes and a low incidence of complications in primary reconstructive surgery of massive bone defect. However, few studies have focused on its usage in revision surgery after failed primary limb-salvage surgery.

METHODS

Between June 2011 and January 2017, 13 patients underwent revision surgery with the Capanna technique for reconstruction of a secondary segmental bone defect caused by a previous failed surgical procedure. The demographics, operating procedures, graft union, functional outcomes, oncologic outcomes, and postoperative complications of each patient were recorded.

RESULTS

The current study investigated 13 patients. The rate of limb salvage was 100 %. Bone union was achieved for all patients during a mean time of 8.54 ± 2.15 months (range 4-11 months) at the fibula-host bone junction and 14.92 ± 2.33 months (range 12-21 months) at the allograft-host bone junction. The postoperative complications included wound healing issues and internal fixation loosening. Allograft fracture, nonunion, and infection were not observed. All the patients achieved good functional outcomes, with a Musculoskeletal Tumor Society (MSTS) score of 0.86 ± 0.03 at the latest follow-up visit.

CONCLUSIONS

The Capanna technique is a reliable alternative method for revision reconstruction of a segmental bone defect caused by a previous failed surgical procedure.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Reconstruction with a Custom made Prosthetic Wrist Arthrodesis after Bone Tumor Resections of the Distal Radius. Single Centre Experience

Objective  The present study aimed at analyzing the clinical, radiological and functional results of the reconstruction of the distal radius after tumor resection with a custom-made metal arthrodesis implant and compare them with other types of distal radius reconstruction, as presented in the literature.

To our best knowledge, this is the first article describing this particular type of implant and patient functionality.

Methods  Functional outcomes of reconstruction of the distal radius were assessed in a series of 4 patients. Three of the patients having had resection of giant cell tumors (GCTs), one patient having had resection of osteosarcoma.

Results  There were no major implant-related complications like infection, nonunion or loosening. Two patients had to undergo further surgery for protruding metalwork. Overall function was good according to the Musculoskeletal Tumor Society MSTS and Disabilities of the Arm, Shoulder, and Hand (DASH) scores.

Conclusion  The present study shows that custom-made metal arthrodesis implant benefits from the fact that it can be used as a salvage option when other treatments have failed, or it can be used as a primary option in cases in which there is limited bone stock after distal radius tumor resection.

Treatment of diaphyseal forearm defects caused by infection using Ilizarov segmental bone transport technique

Background

The Ilizarov segmental bone transport technique can be applied in the reconstruction of the bone defects with less invasive fashion and more versatility compared to other methods, while most studies were focused on the lower extremity. The purpose of this study was to evaluate the effectiveness of the Ilizarov segmental bone transport technique in the treatment of diaphyseal forearm bone defects caused by infection.

Methods

This study included 12 patients with diaphyseal forearm bone defects caused by infection, who underwent bone transport procedures using the monolateral external fixator at our institution from January 2010 to January 2018, including 10 males and 2 females with a mean age of 39 years (range 23–57 years). Patient’s demographic data and clinical outcomes at least two years follow-up after removing the external fixator were collected and retrospectively analyzed. The functional results were evaluated by the questionnaire of Disability of Arm, Shoulder and Hand (DASH) and the modified Mayo wrist score (MWS) at the final follow-up.

Results

There were 10 radii and 2 ulnae bone transport procedures collected. The average defect size was 5.1 cm (4-6.5 cm). All patients were successfully followed up with a mean period of 28.2 months (24 to 36 months) and achieved infection-free union. There was no recurrence of infection observed. The mean external fixation time was 232.6 days (182 to 276 days), and the mean external fixation index was 46.3 days/cm (40.9 to 61.8 days/cm). The mean DASH score was 30.6(18 to 49) preoperative, while 13.8 (5 to 26) at the final follow-up. The average modified MWS improved from 68.8 (55 to 80) pre-operatively to 83.8 (65 to 90) at the final follow-up. All the differences between the preoperative and final scores were statistically significant (p < 0.05). Almost all the patients achieved satisfactory clinical outcomes and were able to perform activities of daily living.

Conclusions

Ilizarov segmental bone transport technique is an alternative and effective method for the treatment of diaphyseal forearm bone defects caused by infection, and this method acquired satisfactory clinical outcomes.

Evading the host response: Staphylococcus "hiding" in cortical bone canalicular system causes increased bacterial burden

Extremity reconstruction surgery is increasingly performed rather than amputation for patients with large-segment pathologic bone loss. Debate persists as to the optimal void filler for this "limb salvage" surgery, whether metal or allograft bone. Clinicians focus on optimizing important functional gains for patients, and the risk of devastating implant infection has been thought to be similar regardless of implant material. Recent insights into infection pathophysiology are challenging this equipoise, however, with both basic science data suggesting a novel mechanism of infection of Staphylococcus aureus (the most common infecting agent) into the host lacunar-canaliculi network, and also clinical data revealing a higher rate of infection of allograft over metal. The current translational study was therefore developed to bridge the gap between these insights in a longitudinal murine model of infection of allograft bone and metal. Real-time Staphylococci infection characteristics were quantified in cortical bone vs metal, and both microarchitecture of host implant and presence of host immune response were assessed. An orders-of-magnitude higher bacterial burden was established in cortical allograft bone over both metal and cancellous bone. The establishment of immune-evading microabscesses was confirmed in both cortical allograft haversian canal and the submicron canaliculi network in an additional model of mouse femur bone infection. These study results reveal a mechanism by which Staphylococci evasion of host immunity is possible, contributing to elevated risks of infection in cortical bone. The presence of this local infection reservoir imparts massive clinical implications that may alter the current paradigm of osteomyelitis and bulk allograft infection treatment.

Clinical Outcome of Free Vascularized Fibula Graft in the Surgical Treatment of Extremity Osteosarcoma

Objective

To determine the clinical outcome and complications associated with use of free vascularized fibular graft (FVFG) in the resection and reconstruction of extremity osteosarcoma (OS).

Methods

This is a retrospective study recruiting a consecutive series of 18 patients who had undergone resection of extremity OS between May 2009 and June 2017 in our clinic center. Reconstruction of the bone defect with FVFG was performed for each patient. Surgery‐related complications and time of bone union were recorded at the follow‐up visit. The functional outcome of the reconstructed limb was assessed with the musculoskeletal tumor society (MSTS) scoring system. Patients were further classified into low extremity group and upper extremity group according to the tumor location. The Student t‐test was used to compare the surgical outcome between the two subgroups.

Results

There were 11 males and seven females with an average age of 25.9 ± 14.2 years. The mean length of the bone resection was 11.9 ± 4.1 cm. The mean follow‐up duration was 3.1 ± 1.2 years. As for tumor location, six cases were located in the femur, five in the tibia, four in the humerus, two in the ulna, and one in the radius. All the patients had successful graft healing at an average of 4.9 months after surgery. At the 2‐year follow‐up, an excellent functional outcome was observed in 88.9% of the patients (n = 16). The mean score of MSTS was 27.0 ± 4.6. Screw loosening and autograft fracture were observed in one patient with femur tumor, who had a low MSTS score of 11. Besides, there were three cases with delayed incision healing. Patients with lower extremity OS were found to have significantly longer duration of hospital stay and more blood loss than those with upper extremity OS. The incidence of postoperative complication was higher in the lower extremity group but with marginal significance (0% vs 36.3%, P = 0.1). There was no significant difference regarding time to bone union and the functional outcome as indicated by MSTS score.

Conclusions

FVFG technique can be effectively applied to the reconstruction of bone defects after OS resection with satisfactory functional outcome and low incidence of complications.

Tips to secure healing at the free vascularised fibular graft-to-host bone junction

The most commonly used vascularized bone graft in Orthopedics for difficult reconstructive problems requiring biological augmentation properties is the fibula. It provides immediate structure and with a patent pedicle, increases blood flow at the recipient site, promoting healing and hypertrophy in response to mechanical stress. The vascular supply from the nutrient branch and the periosteal vessels allows a variety of graft harvesting configurations for a broad spectrum of reconstructive challenges. We present the details on how to optimize healing and graft incorporation at the junction sites.

Onlay vascularized fibular grafting as a salvage procedure for the management of nonunion after reconstruction of the femur following tumor resection

PURPOSE

The femur is prone to nonunion after biologic reconstruction following tumor resection, due to high bending forces. Nonunion at the host-graft junction is difficult to treat since the graft is in an avascular state. We aimed to investigate the clinical and radiographic results of an onlay free vascularized fibular grafting (VFG) as a salvage procedure for nonunion management after biologic reconstruction of the femur following bone tumor resection.

METHODS

We retrospectively reviewed 10 patients (8 men and 2 women, median age: 15.5 years, range: 10-47) who underwent an onlay VFG for nonunion after intercalary reconstruction of the femur using an allograft ( n = 7) or pasteurized autograft ( n = 3), following tumor resection. The median follow-up period after VFG was 85.7 (24.6-163.5) months.

RESULTS

The median time to union between the host bone and the VFG osteotomy sites was 3.5 (2.8-4.5) months. The median time to union at the host-graft junctions was 10.6 (6.6-12.7) months. Two postoperative complications requiring revision surgery occurred in two patients: one graft fracture and one deep infection with synchronous graft fracture. Internal fixation was required in the patient with graft fracture. The patient with the infection and synchronous graft fracture was treated using debridement, antibiotics, and an external fixator. The median Musculoskeletal Tumor Society functional score was 88% (60-97%) at the final follow-up.

CONCLUSION

Onlay VFG as a salvage procedure for nonunion of a biologic intercalary reconstruction of the femur after tumor resection is a useful treatment option.

Effects of Surgical Angiogenesis on Segmental Bone Reconstruction With Cryopreserved Massive-Structural Allografts in a Porcine Tibia Model

Cryopreserved bone allografts (CBA) used to reconstruct segmental bone defects provide immediate structural stability, but are vulnerable to infection, non-union and late stress fracture as the majority of the allograft remains largely avascular. We sought to improve the bone vascularity and bone formation of CBAs by surgical angiogenesis with an implanted arteriovenous (AV) bundle, using a porcine tibial defect model. Cryopreserved tibial bone allografts were transplanted in swine leukocyte antigen (SLA) mismatched Yucatan minipigs to reconstruct a 3.5 cm segmental tibial defect. A cranial tibial AV-bundle was placed within its intramedullary canal to induce angiogenesis. The AV bundle was patent in eight pigs and ligated in a control group of eight pigs. At 20 weeks neo-angiogenesis was evaluated by micro-angiography. Bone formation was measured by quantitative histomorphometry and micro-computed tomography. Seven of eight AV-bundles in the revascularized group were patent. One had thrombosed due to allograft displacement. Total vascular volume was higher in the revascularized allografts compared to the ligated group (p = 0.015). Revascularized allografts had increased levels of bone formation on the allograft endosteal surface compared to the ligated control group (p = 0.05). Surgical angiogenesis of porcine tibial CBAs by intramedullary implantation of an AV-bundle creates an enhanced autogenous neoangiogenic circulation and accelerates active bone formation on allograft endosteal surfaces. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1698-1708, 2019.

One-Barrel Microsurgical Fibula Flap for Reconstruction of Large Defects of the Femur

Various methods for reconstructing large femur bone defects after tumor resection have been introduced. In this study, we reviewed the clinical outcomes of using a 1-barrel free vascularized fibular graft (FVFG) protected by a lateral locking plate for large femoral defects not involving the knee joint.Between August 2007 and August 2013, we treated 7 patients with large femoral bone defects after tumor resection. The mean age of the patients was 19 years (range, 12-36 years), and 3 were women. All defects were free of infection before the procedure. Femoral bone defects were reconstructed using a 1-barrel FVFG protected by a lateral locking plate. The mean bone defect size was 10.5 cm (range, 6-16 cm). We reviewed clinical outcomes at the last follow-up.All patients survived beyond the last follow-up; the mean follow-up period was 54 months (range, 26-100 months). Two patients sustained stress fractures of the FVFG, but the lateral locking plate protected the fractured graft until in situ bone healing obtained. Mean time to bone union of both host-graft junctions was 24 months (range, 18-31 months). The mean Musculoskeletal Tumor Society score (%) was 85.8% (range, 80-95%).A 1-barrel FVFG protected by a lateral locking plate maintained a stable graft-host bone construct, successfully leading to bone healing, even in cases of stress fractures of the graft, and appears to be a good option for large femur bone defects.

Microsurgery in musculoskeletal oncology

Sarcomas are rare mesenchymal bone and soft tissue tumors of the musculoskeletal system. In the past, the primary treatment modality was amputation of the involved limb and the 5-year survival was very low for high-grade tumors. During the last three decades, limb salvage has become the rule rather than the exception and the use of neoadjuvant and adjuvant therapies (radiation and chemotherapy) has dramatically increased disease-free survival. Reconstruction of large bone and soft tissue defects, though, still remains a significant challenge in sarcoma patients. In particular, vascularized tissue transfer has proved extremely helpful in dealing with complex bone and soft tissue or functional defects that are frequently encountered as a result of the tumor or as a complication of surgery and adjuvant therapies. The principles, indications and results of microsurgical reconstruction differ from trauma patients and are directly related not only to the underlying disease process, but also to the local and systemic therapeutic modalities applied to the individual patient. Although plastic reconstruction in the oncological patients is not free of complications, usually these complications are manageable and do not jeopardize oncological outcome. The overall treatment strategy should be tailored to the patient's and sarcoma profile.

Corrective Osteotomy with Autogenous Bone Graft with Callus after Malunion of Distal Radius Fracture

Corrective osteotomy with callus filling at fracture site for malunion after distal radius fracture is a rare technique, but it achieved a favorable postoperative outcome. The patient, 66-year-old female, visited our hospital 4 months after distal radius fracture. Corrective osteotomy of the distal radius was planned aiming at improving the wrist joint function, and was performed using a volar locking plate, then the bone defect was filled with callus as autogenous bone grafting. At 12 months after surgery, left wrist joint pain and the range of motion have improved, and the Mayo wrist score was excellent. To our knowledge, there has been no study on the treatment of bone defects by filling with callus. Since favorable bone fusion was achieved with callus, this treatment method may overcome the disadvantages of autogenous bone graft, such as pain at the donor region.

Treatment of critical-sized bone defects: clinical and tissue engineering perspectives

Critical-sized bone defects are defined as those that will not heal spontaneously within a patient's lifetime. Current treatment options include vascularized bone grafts, distraction osteogenesis, and the induced membrane technique. The induced membrane technique is an increasingly utilized method with favorable results including high rates of union. Tissue engineering holds promise in the treatment of large bone defects due to advancement of stem cell biology, novel biomaterials, and 3D bioprinting. In this review, we provide an overview of the current operative treatment strategies of critical-sized bone defects as well as the current state of tissue engineering for such defects.

The effect of bone morphogenetic protein-2 on osteosarcoma metastasis

Purpose

Bone Morphogenetic Protein-2 (BMP-2) may offer the potential to enhance allograft-host osseous union in limb-salvage surgery following osteosarcoma resection. However, there is concern regarding the effect of locally applied BMP-2 on tumor recurrence and metastasis. The purpose of this project was to evaluate the effect of exogenous BMP-2 on osteosarcoma migration and invasion across a panel of tumor cell lines in vitro and to characterize the effect of BMP-2 on pulmonary osteosarcoma metastasis within a xenograft model.

Experimental design

The effect of BMP-2 on in vitro tumor growth and development was assessed across multiple standard and patient-derived xenograft osteosarcoma cell lines. Tumor migration capacity, invasion, and cell proliferation were characterized. In addition, the effect on metastasis was measured using a xenograft model following tail-vein injection. The effect of exogenous BMP-2 on the development of metastases was measured following both single and multiple BMP-2 administrations.

Results

There was no significant difference in migration capacity, invasion, or cell proliferation between the BMP-2 treated and the untreated osteosarcoma cell lines. There was no significant difference in pulmonary metastases between either the single-dose or multi-dose BMP-2 treated animals and the untreated control animals.

Conclusions

In the model systems tested, the addition of BMP-2 does not increase osteosarcoma proliferation, migration, invasion, or metastasis to the lungs.

Functional outcome of en bloc excision and custom prosthetic replacement for giant cell tumor of the distal radius

BACKGROUND

Giant cell tumors (GCT) of the distal radius at Campanacci grade II/III are particularly challenging to treat. Wide excision is the management of choice, but this creates a defect at the distal end of radius. We treated 11 cases of GCT of the distal radius by en bloc excision and custom prosthetic replacement. The purpose of this study was to present our experience and assess the functional outcomes of all patients treated with this surgery.

MATERIALS AND METHODS

Between 2005 and 2014, we followed up 11 patients with GCT of the distal radius who were treated with en bloc excision and custom prosthetic replacement. All cases were evaluated based on clinical and radiological examinations, passive range of motion (ROM) of the wrist joint, complications, and Musculoskeletal Tumor Society (MSTS) score.

RESULTS

Mean follow-up period was 55.5 months (24-83 months); mean resected length of the radius was 7.9 cm. One patient had tumor recurrence in the soft tissues after 15 months (recurrence rate 9.09 %). No patient had fracture, recurrence in the bone, metastases, or immune rejection. No complications were seen, such as loosening, rupture, or dislocation of the custom prosthesis. One patient developed superficial infection at the operative site which resolved after a course of antibiotics for 4 weeks. One patient experienced pain, which could be endured without the need for analgesics. Average ROM was 40.9° of dorsiflexion, 30.0° of volar flexion, 46.4° of supination, and 38.2° of pronation. Mean grip strength was 71 % (42-86 %). Overall revised MSTS score averaged 80.3 % (63.3-93.3 %) with one being excellent, five good, and five satisfactory.

CONCLUSION

En bloc excision and custom prosthetic replacement for a Campanacci grade II/III GCT of the distal radius results in reasonable functional outcome at intermediate follow-up evaluation. Although average ROM of the ipsilateral wrist is poorer than some studies with other techniques, this method can be considered a reasonable option.

The vascularised fibular graft for limb salvage after bone tumour surgery

Vascularised fibular grafts (VFGs ) are a valuable surgical technique in limb salvage after resection of a tumour. The primary objective of this multicentre study was to assess the risk factors for failure and complications for using a VFG after resection of a tumour.

The study involved 74 consecutive patients (45 men and 29 women with mean age of 23 years (1 to 64) from four tertiary centres for orthopaedic oncology who underwent reconstruction using a VFG after resection of a tumour between 1996 and 2011. There were 52 primary and 22 secondary reconstructions. The mean follow-up was 77 months (10 to 195).

In all, 69 patients (93%) had successful limb salvage; all of these united and 65 (88%) showed hypertrophy of the graft. The mean time to union differed between those involving the upper (28 weeks; 12 to 96) and lower limbs (44 weeks; 12 to 250). Fracture occurred in 11 (15%), and nonunion in 14 (19%) patients.

In 35 patients (47%) at least one complication arose, with a greater proportion in lower limb reconstructions, non-bridging osteosynthesis, and in children. These complications resulted in revision surgery in 26 patients (35%).

VFG is a successful and durable technique for reconstruction of a defect in bone after resection of a tumour, but is accompanied by a significant risk of complications, that often require revision surgery. Union was not markedly influenced by the need for chemo- or radiotherapy, but should not be expected during chemotherapy. Therefore, restricted weight-bearing within this period is advocated.

Cite this article: Bone Joint J 2015;97-B:853–61.

Is the Induced-membrane Technique Successful for Limb Reconstruction After Resecting Large Bone Tumors in Children?

BACKGROUND

Resection of primary malignant tumors often creates large bony defects. In children, this creates reconstructive challenges, and many options have been described for limb salvage in this setting. Studies have supported the use of an induced-membrane technique after placement of a cement spacer to aid in restoration of bone anatomy.

QUESTIONS/PURPOSES

We asked: (1) What complications are associated with the induced-membrane technique? (2) How often is bone healing achieved after resection greater than 15 cm using this technique? (3) What is the functional outcome of patients treated with this technique?

METHODS

We performed a retrospective evaluation of eight patients with a mean age of 13.3 years (range, 11-17 years) treated for a malignant bone tumor between 2002 and 2012 at our centers. The primary malignant tumors involved the proximal humerus, femur, and tibia. All patients were treated using the induced-membrane technique after a resection with mean bone loss of 18 cm (range, 16-23 cm). The general indication for using the induced-membrane technique during this time was a large diaphyseal defect after resection of the tumor. In addition to using cancellous graft as with the original technique, in the current patients an autogenous nonvascularized fibula was used to enhance stability. The patients were assessed at the last followup using the Musculoskeletal Tumor Society (MSTS) scoring system. Mean followup was 47.1 months (range, 24-120 months), and none of the patients were lost to followup before 2 years.

RESULTS

A total of four unplanned reoperations were performed in these eight patients. A fracture of the reconstruction occurred in three patients and all were treated successfully, two with surgery and one with immobilization. Bone fusion was obtained in all patients within 4 to 8 months (mean, 5.6 months) after the reconstruction. The mean healing index was 0.31 month/cm of reconstruction (range, 0.23-0.5 month/cm). At last followup, the mean MSTS score was 74% (range, 67%-80%).

CONCLUSIONS

Our findings suggest that the modified induced-membrane technique is a reasonable alternative to other limb reconstruction techniques for bone tumors in children and has the advantage of not requiring a bone bank or an expensive metal prosthesis. Although more patients will be needed to substantiate our findings, it has become a standard part of our arsenal in the treatment of large bone defects after resection of pediatric primitive bone tumors.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

New options for vascularized bone reconstruction in the upper extremity

Originally described in the 1970s, vascularized bone grafting has become a critical component in the treatment of bony defects and non-unions. Although well established in the lower extremity, recent years have seen many novel techniques described to treat a variety of challenging upper extremity pathologies. Here the authors review the use of different techniques of vascularized bone grafts for the upper extremity bone pathologies. The vascularized fibula remains the gold standard for the treatment of large bone defects of the humerus and forearm, while also playing a role in carpal reconstruction; however, two other important options for larger defects include the vascularized scapula graft and the Capanna technique. Smaller upper extremity bone defects and non-unions can be treated with the medial femoral condyle (MFC) free flap or a vascularized rib transfer. In carpal non-unions, both pedicled distal radius flaps and free MFC flaps are viable options. Finally, in skeletally immature patients, vascularized fibular head epiphyseal transfer can provide growth potential in addition to skeletal reconstruction.

Vascularised fibular grafts as a salvage procedure in failed intercalary reconstructions after bone tumour resection of the femur

Vascularised fibular grafts (VFGs) are widely used for primary reconstruction of long bones after bone tumour resections. The biological properties of VFGs are such that they can be a useful option even in failed intercalary reconstructions. The purpose of the current study was to investigate the results and the morbidity of VFGs as a salvage procedure in failed previous reconstructions after intercalary bone tumour resection of the femur. Our series included 12 patients, treated from April 1989 to March 2005, with an average age of 23 years (range 10-43 years) at presentation. The initial diagnosis was osteosarcoma in 10 cases and Ewing's sarcoma in two cases. All patients received chemotherapy and none received radiation therapy. Seven patients received VFG as biologic augmentation in intercalary allograft non-union and in the other five patients, a combination of allograft and VFG was used to replace a cement spacer with hardware failure (four patients) and a failed intercalary prosthesis (one patient). Three patients died during follow-up, in all cases because of metastatic disease. At an average follow-up of 147 months (range 11-260 months), the remaining nine patients were continuously disease-free. Complete healing of the osteotomy of both allograft and VFG was observed in 10 patients at final follow-up. Two major complications were observed that required surgical revision, eventually healing in one case and leading to a poor functional outcome in one case. Significant hypertrophy of the VFG was detected in seven of nine evaluable patients. At final follow-up the mean Musculoskeletal Tumour Society (MSTS)'93 functional score of the nine evaluable patients was 90% (range 66-100%). These results indicate that VFG is a valid salvage procedure in failed intercalary reconstructions of the femur after bone resection.

Surgical technique: Tibia cortical strut autograft interposition arthrodesis after distal radius resection

BACKGROUND

Distal radius reconstruction after en bloc tumor resection remains a surgical challenge. Although several surgical techniques, either reconstructing the wrist or achieving a stable arthrodesis, have been described, it is unclear to what degree these restore function.

DESCRIPTION OF TECHNIQUE

We describe an updated technique making use of a tibia cortical strut autograft (TCSA) to perform a functional arthrodesis from the remaining radius to the first carpal row. This, in theory, could lead to less donor site morbidity while resulting in a stable but functional and pain-free arthrodesis of the wrist.

METHODS

Between 1987 and 2010 we reconstructed the wrists of 17 patients using a TCSA arthrodesis (six primary and three revisions), seven with an osteoarticular allograft, three using an ulnar translocation, and one with a fibula autograft. Median age at diagnosis was 24 years (range, 9-58 years) and minimum followup was 2.7 years (median, 13.8 years; range, 2.7-24.5 years). Patients were evaluated using radiographs and clinical examination. We used Musculoskeletal Tumor Society (MSTS), Disabilities of the Arm, Shoulder, and Hand (DASH), and SF-36 questionnaires to assess function and quality of life.

RESULTS

All TCSA reconstructions fused; one patient had a second surgery to expedite union with the carpal row. After osteoarticular allograft, five patients were revised (three to a TCSA) for nonunion, fracture, or joint collapse. ROM and grip strength were comparable in both AO and TCSA, all above 60% of the contralateral side. Median MSTS and DASH scores were 73% and 6, respectively, and did not differ between the groups. The SF-36 scores showed less pain after TCSA; otherwise, all patients presented with comparable function.

CONCLUSIONS

TCSA wrist arthrodesis resulted in a functional and painless wrist reconstruction with a relatively low complication and donor site morbidity rate and comparable functional results as other techniques.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Mesenchymal stem cell transplantation to promote bone healing

An overall decline in the availability of osteogenic precursor cells and growth factors in the bone marrow microenvironment have been associated with impaired bone formation and osteopenia in humans. The objective of the current study was to determine if transplantation of mesenchymal stromal cells (MSC) from a healthy, young donor mouse into an osteopenic recipient mouse could enhance osseointegration of a femoral implant. MSC harvested from normal young adult mice differentiated into bone forming osteoblasts when cultured on implant grade titanium surfaces ex vivo and promoted bone formation around titanium-coated rods implanted in the femoral canal of osteopenic recipient mice. Micro computed tomographic imaging and histological analyses showed more, better quality, bone in the femur that received the MSC transplant compared with the contra-lateral control femur that received carrier alone. These results provide pre-clinical evidence that MSC transplantation promotes peri-implant bone regeneration and suggest the approach could be used in a clinical setting to enhance bone regeneration and healing in patients with poor quality bone.

Factors affecting outcome of massive intercalary bone allografts in the treatment of tumours of the femur

We retrospectively reviewed 101 consecutive patients with 114 femoral tumours treated by massive bone allograft at our institution between 1986 and 2005. There were 49 females and 52 males with a mean age of 20 years (4 to 74). At a median follow-up of 9.3 years (2 to 19.8), 36 reconstructions (31.5%) had failed. The allograft itself failed in 27 reconstructions (24%).

Mechanical complications such as delayed union, fracture and failure of fixation were studied. The most adverse factor on the outcome was the use of intramedullary nails, followed by post-operative chemotherapy, resection length > 17 cm and age > 18 years at the time of intervention. The simultaneous use of a vascularised fibular graft to protect the allograft from mechanical complications improved the outcome, but the use of intramedullary cementing was not as successful.

In order to improve the strength of the reconstruction and to advance the biology of host–graft integration, we suggest avoiding the use of intramedullary nails and titanium plates, but instead using stainless steel plates, as these gave better results. The use of a supplementary vascularised fibular graft should be strongly considered in adult patients with resection > 17 cm and in those who require post-operative chemotherapy.

Femoral loads during gait in a patient with massive skeletal reconstruction

BACKGROUND

Biological massive skeletal reconstructions in tumours adopt a long rehabilitation protocol aimed at minimising the fracture risk. To improve rehabilitation and surgical procedures it is important to fully understand the biomechanics of the reconstructed limb. The aim of the present study was to develop a subject-specific musculoskeletal model of a patient with a massive biological skeletal reconstruction, to investigate the loads acting on the femur during gait, once the rehabilitation protocol was completed.

METHODS

A personalised musculoskeletal model of the patient's lower limbs was built from a CT exam and registered with the kinematics recorded in a gait analysis session. Predicted activations for major muscles were compared to EMG signals to assess the model's predictive accuracy.

FINDINGS

Gait kinematics showed only minor discrepancies between the two legs and was compatible with normality data. External moments showed slightly higher differences and were almost always lower on the operated leg exhibiting a lower variability. In the beginning of the stance phase, the joint moments were, conversely, higher on the operated side and showed a higher variability. This pattern was reflected and amplified on the femoral forces where the differences became important: on the hip, a maximum difference of 1.6 BW was predicted. The variability of the forces seemed, generally, lower on the operated leg than on the contralateral one.

INTERPRETATION

Small asymmetries in kinematic patterns might be associated, in massive skeletal reconstruction, to significant difference in the skeletal loads (up to 1.6 BW for the hip joint reaction) during gait.

A rare periosteal diaphyseal lesion of the ulna

Periosteal lesions of the ulna diaphysis are rare, include a wide spectrum of tumors, and may cause considerable diagnostic problems. Surgical treatment may vary widely, based on an accurate diagnosis. We present the case of a periosteal, extraskeletal low grade myxoid chondrosarcoma of the ulna diaphysis. The surgical therapy included an en-bloc resection with allograft reconstruction. The patient showed a favorable outcome. Careful preoperative evaluation and planning are imperative to obtain a satisfactory oncological and functional outcome, especially with uncommon tumor presentations at rare locations.

Forearm reconstruction with bone allograft following tumor excision: a series of 10 patients with a mean follow-up of 10 years

BACKGROUND

After a tumor resection, the reestablishment of the bone continuity at the forearm remains a challenge for restoring the biomechanics of hand and elbow. Bone allograft might be one option to consider amongst other suitable alternatives but there are insufficient data available to substantiate its value.

PATIENTS AND METHODS

We retrospectively investigated a series of 10 consecutive patients that had presented a bone tumor at the forearm. After bone excision, the segmental loss was replaced either by a bone allograft or an osteochondral allograft. Patients were reviewed clinically and with radiographs.

RESULTS

The mean follow-up was 110 ± 99 months. Fracture of the allograft was the most prevalent complication occurring in four patients, mainly in the osteoarticular group. Four patients were surgically revised: two of them had a fracture of the allograft that required a new one, another one had a painful stiff wrist requiring removal of the allograft and arthrodesis with autograft and the fourth one had a non-union of an intercalary allograft that was treated by a distal ulnar joint resection. Intercalary allograft had fewer complications than osteoarticular allografts and they had a better functional MSTS score with an average of 79% of a normal function compared to osteoarticular allografts with an average score of 62%. There was no infection. At the latest follow-up, one reconstruction of the forearm with an allograft failed and concerned the distal radius joint.

DISCUSSION

A bone allograft when available can be considered as one amongst other suitable options for the reconstruction of the forearm skeleton.

Surgical difficulties encountered with use of modular endoprosthesis for limb preserving salvage of failed allograft reconstruction after malignant tumor resection

We reviewed outcomes and discussed surgical difficulties encountered in 10 patients who had modular endoprosthesis for limb preserving salvage of failed allograft reconstruction after malignant tumor resection. Mean allograft survival time before failure was 127.4 months (range, 14-264 months). Mean length of follow-up since endoprosthesis revision surgery was 62.8 months (range, 16-132 months). There was one endoprosthesis failure, resulting in a mean endoprosthesis survival time of 56.9 months (range, 16-132). Complications included arterial laceration, nerve injury, periprosthetic crack fracture, aseptic loosening, and infection. Modular endoprosthesis remain a viable option that should be considered in any limb preserving salvage of failed allograft reconstructions. However, altered anatomy, poor/short remnant host bone, periprosthetic fractures, inadequate soft tissue coverage and infection remain important difficulties encountered.

Biological reconstruction using massive bone allograft with intramedullary vascularized fibular flap after intercalary resection of humeral malignancy

BACKGROUND

Reconstruction after excision of the humeral malignancy is a challenging issue for the reconstructive surgeon. The combined use of a fibular flap and allograft can provide a reliable reconstructive option. This article describes the authors' experience with this technique for the treatment of segmental bone defects after resection of humeral malignancy.

METHODS

From 2005 to 2008, seven patients that had intercalary resection of humeral malignancy underwent reconstruction with an allograft and vascularized fibula construct. Patients were examined clinically and radiographically.

RESULT

The average age at time of operation was 16.7 years. The mean follow-up time was 27.7 months. The average length of the resected humeral segment was 10.6 cm and that of the fibula flap was 13.1 cm. The average time of union of fibula was 20.7 weeks and for union of allograft was 26.3 weeks. Incorporation of the fibula into the allograft was seen in three patients. There were no allograft fractures and no infections. Three patients had surgery-related complications including a temporary radial nerve paralysis in 1, wound dehiscence in 1, and clawed toes in 1. The MSTS average score was 95.2% at final follow-up.

CONCLUSIONS

Intramedullary fibular flaps in combination with massive allografts provide an excellent option for reconstruction of large bony defects after humeral malignancy extirpation. The viability of the fibula is a cornerstone in success of reconstruction that prevents allograft nonunion and result in decreased time to bone healing, leading to earlier patient recovery and return of function.

A modified vascularized whole knee joint allotransplantation model in the rat

Previous papers have shown surgical neoangiogenesis to allow long-term bone allotransplant survival without immunosuppression. Whole joint composite tissue allotransplants (CTA) might be treated similarly. A novel rat knee CTA model is described for further study of the roles of neoangiogensis in joint allotransplant survival and adjustment of immunosuppression. Microvascular knee CTA was performed in nine rats across a major histocompatibility barrier with both pedicle repair and implantation of host-derived arteriovenous ("a/v") bundles. In the control group (N = 3), the pedicle was ligated. Immunosuppression was given daily. Joint mobility, weight-bearing, pedicle patency, bone blood flow, and sprouting from a/v bundles were assessed at 3 weeks. All but the nonrevascularized control knees had full passive motion and full weight bearing. One nutrient pedicle thrombosed prematurely. Blood flow was measurable in transplants with patent nutrient pedicles. Implanted a/v bundles produced new vascular networks on angiography. This new rat microsurgical model permits further study of joint allotransplantation. Patency of both pedicles and implanted a/v bundles was maintained, laying a foundation for future studies.

Role of mechanical loading in healing of massive bone autografts

We assessed healing of a 3.5 cm autograft transport segment, denuded of periosteum, and docked to the healthy distal femur with an intramedullary nail. We hypothesized that healing relates to proximity to the healthy distal femur and to mechanical loading patterns. Total bone area, area of new bone apposition, and quality of new bone formed in the 2 weeks after surgery, and area and degree of perfusion 16 weeks after surgery were measured as a function of proximity and loading patterns (as defined by the major and minor centroidal axes, CA). At 16 weeks, no significant differences in early bone apposition or perfusion were observed as a function of distance from the healthy distal femur. Qualitatively, bone was well perfused, both vascularly and pericellularly, and highly remodeled. When cross-sections were pooled from distal to proximal through the docking zone and normalized for total bone area, significant differences in the amount of early proliferative woven bone were related to loading patterns. In contrast, no differences in normalized perfusion area were attributable to loading patterns. Furthermore, early bone apposition and perfusion decreased with increasing radial distance from the bone surface toward the intramedullary nail. Finally, no differences were observed in areas of resorption within the docking zone compared to baseline levels measured in the control (in bone removed to create the defect zone at the time of surgery). Interestingly, infilling of resorption spaces within docking zone specimens related significantly to predominant loading patterns, where areas within the major CA exhibited significantly more infilling.

Is combining massive bone allograft with free vascularized fibular flap the children's reconstruction answer to lower limb defects following bone tumour resection?

PURPOSE OF THE STUDY

Bone tumours are frequent conditions in children, and their surgical resection may lead to extensive defects which reconstruction is often challenging. Indeed, local conditions do not promote bone healing, and the achieved surgical result requires to be life-lasting. Capanna suggested a reconstruction technique combining massive allograft and free vascularized fibular flap. The first one is intended to withstand mechanical stress, and the second one offers biological and vascular support to improve bone healing and prevent infections.

MATERIAL AND METHODS

We report our experience with this technique when applied to the lower limb in a prospective study including seven children, with a mean follow-up of 44 months.

RESULTS

Bone healing was achieved by one single procedure in 85.7% of the cases, usually 7 months after surgery. Six out of seven patients achieved a final and long-lasting outcome, five of them following a simple surgical history. Partial weight-bearing was post-operatively allowed at about 2 months, full weight-bearing was initiated at about 5.5 months.

DISCUSSION

A low complication rate was reported despite the extent of the disease and the type of the surgical procedure. Capanna's combined reconstructive technique appears very efficient in the management of massive bone defects following tumour resection in children's lower limb.

LEVEL OF EVIDENCE

Level IV. Retrospective therapeutic study.

Long-term results for limb salvage with osteoarticular allograft reconstruction

Osteoarticular allograft reconstruction after extremity tumor resection has been shown to have a high rate of complications. Although good functional results have been seen, long-term outcomes have not been well studied. We performed a retrospective review of 20 patients who underwent primary osteoarticular allograft reconstruction after extremity sarcoma resection. All postoperative complications related to the allograft reconstruction were recorded. Musculoskeletal Tumor Society 1993 and Toronto Extremity Salvage Score scores were used for functional evaluation at last followup. Minimum followup was 10 years (mean, 16 years; range, 10-21 years). Seventy percent of patients experienced an event during the followup period. Recorded events were fracture (nine patients), progressive arthritis (five), nonunion (four), and infection (two). Sixty percent of allografts were removed at a mean of 5.2 years. Progressive arthritis led to total joint arthroplasty in five patients (25%). Mean Musculoskeletal Tumor Society and Toronto Extremity Salvage Score functional scores were 25 of 30 and 95% for patients who retained their original allograft. Osteoarticular allograft reconstruction for extremity sarcomas had a high rate of adverse events (70%) and allograft removal (60%) at long-term followup. Functional outcomes of patients with intact grafts were comparable to outcomes with segmental replacement prostheses reported in the literature.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Bone tumors: osteosarcoma and Ewing's sarcoma

PURPOSE OF REVIEW

Osteosarcoma and Ewing's sarcoma are the two most common primary malignant bone tumors in children and account for approximately 6% of all childhood malignancies. Treatment methods have seen significant advancements, particularly in regard to chemotherapy and limb-sparing surgery. These advancements have led to increased survival rate. With many long-term survivors, it is important to evaluate long-term patient outcomes following treatment, including function and health-related quality of life. We will review the current trends in treatment of these diseases, different reconstructive options available, and the methods and results for evaluating the long-term results.

RECENT FINDINGS

There have been many improvements in the medical treatment of these tumors leading to increasing long-term survival. There have also been improvements in reconstructive techniques for the maintenance of functional extremities in these patients. Newer evaluation methods for both functional outcome and health-related quality of life measures that are more specific to children and adolescents are being developed and in use.

SUMMARY

This report will provide an overview of the current treatment options and long-term complications in primary malignant bone tumors for the pediatrician caring for a child with these problems.

Case reports: lengthening of a vascularized free fibular graft

Wide bone resection is sometimes necessary for bone tumors, and reconstruction is a major challenge. Vascularized fibular graft is one alternative but may result in progressive limb-length discrepancy (LLD) in children with substantial growth left. Progressive distraction lengthening with an external fixator is now a standard procedure to generally correct LLD. However, lengthening of free vascularized fibular grafts for lower limb reconstruction has not been reported frequently and then only in small series or case reports. We report our experience with three patients with lengthening after tibial reconstruction with a free vascularized fibular graft and review the literature.