Tibial Reconstruction Research Articles

CORR Insights®: Does Local Zoledronate Applied to Pasteurized Bone Autografts Improve the Likelihood of Union of Graft-Host Junctions after Limb-sparing Surgery?

CORR Insights®: Does Local Zoledronate Applied to Pasteurized Bone Autografts Improve the Likelihood of Union of Graft-Host Junctions after Limb-sparing Surgery?

Custom-made endofemoral sleeves in knee revision surgery: case report and technical notes

Revision total knee arthroplasty is a challenging procedure for every orthopaedic surgeon, especially when a megaprosthesis is involved. Possible surgical solutions in case of distal femur megaprosthesis revision are total femoral replacement (TFR) or amputation/disarticulation. TFR is affected by an extremely high rate of complications, while amputation/ disarticulation leads to unacceptable functional results. We report the case of a 59-year-old woman who underwent a staged left knee megaprosthesis revision for infection with massive femoral and tibial bone loss and complete disruption of extensor mechanism following 7 prior surgeries. To manage these problems, we developed a new, custom porous titanium endofemoral sleeve for the femoral side and a custom porous titanium cone for tibial reconstruction that were tailored to the patient’s specific bone loss and matched with the tumor prosthetic design used. A custom-made endofemoral sleeve may be a viable solution introducing an intermediate step between distal femur megaprosthesis and total femur substitution. Accurate and detailed surgical planning as well as intraoperative management of soft tissues and residual bone stock are key factors for optimal outcomes.

Vascularized Pedicled Fibula for Pediatric Tibia Reconstruction

This video reviews the technique of a vascularized fibula flap for pediatric tibia reconstruction. A 4-year-old boy with a history of a left tibial infected nonunion status after multiple debridements presented with segmental bone loss and difficulty with ambulation. An ipsilateral vascularized fibula flap was used for reconstruction. The patient proceeded to union and was independently ambulatory with bracing.

Early Experience with Femoral and Tibial Bone-Anchored Osseointegration Prostheses.

Background:The use of bone-anchored osseointegration implants for amputation reconstruction continues to expand throughout the world. Benefits are thought to include the elimination of socket-related problems and improved control and proprioception of the prosthetic limb. Reported outcomes have been positive, but skepticism remains with regard to the risk of infection and implant failure. Further results from early adopters are therefore needed prior to widespread acceptance and regulatory approval.Methods:A retrospective review of the first 31 consecutive patients who underwent implantation of a press-fit osseointegration implant of the femur or tibia with follow-up of at least 6 months was performed. The primary outcome was the patient-reported Questionnaire for persons with a Transfemoral Amputation (Q-TFA) measured preoperatively and 6 to 12 months postoperatively. Patient-Reported Outcomes Measurement Information System (PROMIS) and Limb Deformity-Scoliosis Research Society (LD-SRS) scores, 2-minute and 6-minute walk tests, and complications were also recorded.Results:In this study, 18 femoral reconstructions and 13 tibial reconstructions were performed, with a mean follow-up (and standard deviation) of 21.1 ± 9.2 months. Twenty-eight reconstructions were single-stage implantations. All Q-TFA domains improved significantly (p < 0.001) from preoperatively to postoperatively, including the global score (25.0 ± 17.4 to 81.2 ± 17.6 points), prosthetic use (50.2 ± 39.9 to 91.2 ± 18.7 points), prosthetic mobility (49.7 ± 26.9 to 81.4 ± 21.5 points), and prosthetic problems (46.4 ± 17.5 to 9.1 ± 6.6 points). The overall and functional outcome domains of the PROMIS and LD-SRS and the 2-minute walk test (243 ± 107 to 369 ± 151 ft [74 ± 33 to 112 ± 46 m]; p = 0.022) and 6-minute walk test (609 ± 323 to 1,054 ± 555 ft [186 ± 98 to 321 ± 169 m]; p = 0.016) also improved significantly. Serious adverse events included 2 periprosthetic hip fractures, 1 explantation for septic loosening, and 1 explantation for aseptic loosening, with an overall implant retention of 93%. The most common complication was low-grade, soft-tissue infection requiring oral antibiotics.Conclusions:Similar to the early experience of other international centers, osseointegration implants improved the overall and functional experience of patients compared with socket prosthetics. Complications were present but manageable and were not a deterrent to ongoing support of the technology.Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal Tibial Reconstruction in the Management of Primary Bone Tumors in Children and Adolescents.

Distal tibial primary bone tumors are rare, and options for limb salvage surgery are limited and challenging. Importantly, local control has shown to be crucial and necessary for cure, and radical surgery is one of the most important components of therapy for some bone sarcomas. We investigated the feasibility and functional and oncological outcomes of distal tibial reconstruction using endoprosthesis in children with malignant bone tumors. Fourteen patients (median age 13.6 years) with primary bone tumors (4 Ewing sarcoma [ES], 10 osteosarcoma) of the distal tibiae were treated during 2013-2019. All patients had reconstruction using a modular (13 patients) or expandable custom-made titanium bone replacement system (1 patient). All patients received chemotherapy before and after surgery. Twelve patients (85.7%) are alive with a median follow-up 20 months from diagnosis. Five-year estimates of event-free survival and overall survival were 60.6% and 76.4%, respectively. Three patients had postoperative complications requiring second surgery. Maximum dorsiflexion and plantar flexion of the foot were 20 degrees (range 0-20 degrees) and 20 degrees (range 5-20 degrees), respectively. For select distal tibial sarcomas, after neoadjuvant chemotherapy pretreatment and radical resection, reconstruction using an endoprosthesis as a radical surgery provides an option was associated with a low rate of short-term local complications and relatively good early function. Level IV, therapeutic study.

Clinically Important Reductions in Physical Function and Quality of Life in Adults with Tumor Prostheses in the Hip and Knee: A Cross-sectional Study.

Clinically Important Reductions in Physical Function and Quality of Life in Adults with Tumor Prostheses in the Hip and Knee: A Cross-sectional Study.

DISTAL TIBIAL RECONSTRUCTION WITH INTRAMEDULLARY NAIL COMBINED WITH T-PLATE FOLLOWING EN-BLOC-EXCISION OF GIANT CELL TUMOR OF DISTAL TIBIA: CASE-REPORT

Background: Giant cell tumor is locally aggressive benign tumor that occur more common in distal femur, proximal tibia, and distal radius, and has tendency for recurrence and has capability for metastatize. Giant cell tumor in foot ankle are rare, and comprise less than four percent of giant cell tumor of the bone.Case Report: A 33 years old man presented with complains of pain and swelling in right ankle since 6 months ago with no history of trauma. Physical examination revealed increasing swelling over the distal-posteromedial aspect of lower leg and limitation ankle movements due to pain. Routine blood investigations showed slight increase of alkaline phosphatase. X-ray and Magnetic Resonance Imaging showed the lesion with morphology suggestive of giant cell tumor. Histopathology examination showed multinucleated giant cells and spindle shaped of mononuclear cells suggestive of giant cell tumor. The patient was treated with en-bloc-excision followed with distal tibial reconstruction using reverse intramedullary tibial nail combined with T-plate (tibio-talar arthodesis).Discussion: The main treatment of giant cell tumor of the bone is surgical removal to achieve tumor-free by eradication of the tumor, with various surgical techniques for reconstructing the cavity left. In this case we performed distal tibial reconstruction using reverse intramedullary tibial nail combined with T-plate.Conclusion: The patient at 12-month follow up is doing well, walking comfortably without any pain, has no limitation in range of motion with no signs of recurrence and good MSTS score (90).

Clinical and radiological assessment of the induced membrane technique using beta-tricalcium phosphate in reconstructive surgery for lower extremity long bone defects.

To clarify the effectiveness of the induced membrane technique (IMT) using beta-tricalcium phosphate (β-TCP) for reconstruction of segmental bone defects by evaluating clinical and radiological outcomes, and the effect of defect size and operated site on surgical outcomes. A review of the medical records was conducted of consecutive 35 lower limbs (30 males and five females; median age 46 years (interquartile range (IQR) 40 to 61)) treated with IMT using β-TCP between 2014 and 2018. Lower Extremity Functional Score (LEFS) was examined preoperatively and at final follow-up to clarify patient-centered outcomes. Bone healing was assessed radiologically, and time from the second stage to bone healing was also evaluated. Patients were divided into ≥ 50 mm and < 50 mm defect groups and into femoral reconstruction, tibial reconstruction, and ankle arthrodesis groups. There were ten and 25 defects in the femur and tibia, respectively. Median LEFS improved significantly from 8 (IQR 1.5 to 19.3) preoperatively to 63.5 (IQR 57 to 73.3) at final follow-up (p < 0.001). Bone healing was achieved in all limbs, and median time from the second stage to bone healing was six months (IQR 5 to 10). Median time to bone healing, preoperative LEFS, or postoperative LEFS did not differ significantly between the defect size groups or among the treatment groups. IMT using β-TCP provided satisfactory clinical and radiological outcomes for segmental bone defects in the lower limbs; surgical outcomes were not influenced by bone defect size or operated part. Cite this article: Bone Joint J2021;103-B(3):456-461.

A case of tibial reconstruction using Masquelet technic for sequestrum after vascularized fibula grafts

A case of tibial reconstruction using Masquelet technic for sequestrum after vascularized fibula grafts

Micromotion Analysis of Various Tibial Constructs in Moderate Tibial Defects in Revision Total Knee Arthroplasty

BackgroundThe purpose of this study is to compare the micromotion of various tibial reconstruction strategies including short cemented and long cementless stems with or without metaphyseal augmentation. MethodsA moderate tibial bone defect was milled into dual density polyurethane test blocks. Mechanical testing was performed on 4 test constructs: (1) short cemented stem (75-mm total length) alone; (2) short cemented stem with a symmetric metaphyseal cone; (3) a press-fit (175-mm total length) diaphyseal engaging tibial construct without a cone, and (4) the same press-fit tibial construct with a metaphyseal cone augment. Micromotion of the baseplate/cone construct with respect to the tibia block was measured during a stair descent loading profile for 10,000 cycles. The peak-to-peak micromotion of these various tibial constructs was compared. Unpaired t-tests were used to evaluate differences in peak-to-peak micromotion among the various tibial constructs tested. An analysis of variance was performed for final validation. ResultsThe cemented short stem demonstrated similar varus/valgus displacement, internal/external rotation, compression, and lift-off micromotion values under loading compared to a cementless long stem. A tibial cone improved compression and lift-off micromotion for both cemented and cementless constructs. A short 50-mm cemented stem with a cone demonstrated a lower micromotion at the anterior SI location compared to a press-fit 150-mm cementless stem without a tibial cone. ConclusionsA short cemented tibial component with a cone achieved similar micromotion during simulated stair descent compared to a cementless diaphyseal press-fit implant in cases of moderate tibial defects

Evaluation of a novel lower radiation computed tomography protocol for assessment of tunnel position post anterior cruciate ligament reconstruction

BackgroundAnterior cruciate ligament (ACL) reconstruction is a common orthopaedic procedure. We developed a novel, low dose computed tomography (LDCT) protocol to assess tunnel position post-operatively. The effective radiation dose of this protocol is < 0.5millisieverts (mSv), which is significantly less than the 2 mSv dose for a conventional CT protocol. The aim of this study was to assess the accuracy of the LDCT protocol for determining tunnel position.MethodsTwenty-six patients who underwent primary ACL reconstruction were included in the study. A LDCT scan was performed 6 weeks post-operatively. Femoral and tibial tunnel positions were measured on three dimensional (3D) reconstructions using previously validated techniques. Measurements were performed independently by three observers at two time points, 4 weeks apart.ResultsThere was excellent intra- and inter-rater reliability for all measurements using the images obtained from the LDCT protocol. Intra-class correlation coefficient (ICC) values were > 0.9 for all measurements.ConclusionsThe LDCT protocol described in this study accurately demonstrates femoral and tibial tunnels post ACL reconstruction, while exposing the patient to a quarter of the radiation dose of a conventional CT. This protocol could be used by orthopaedic surgeons for routine post-operative imaging, in place of plain film radiographs.

Intercalary Allograft to Reconstruct Large-Segment Diaphysis Defects After Resection of Lower Extremity Malignant Bone Tumor.

AimTo evaluate the clinical effect of intercalary allograft transplantation and reconstruction in the treatment of diaphyseal defect after resection of lower extremity malignant bone tumor.MethodsClinical data of 17 patients diagnosed with malignant lower-limb bone tumors and having undergone segmental allograft reconstruction with a mean follow-up of 49.8 (26–78) months were included. Segmental allografts of average 17-cm length preserved by deep-freezing were used and fixed using intramedullary nail, double plate, and intramedullary nail and plate combination in 2, 5, and 10 patients, respectively. Host–donor junctions were perfectly and roughly matched in 5 and 12 patients, respectively. Allograft union, local recurrence, and complications were assessed using clinical and radiological tests. Allograft union was evaluated using the International Society of Limb Salvage (ISOLS) scoring system. The functional prognosis was evaluated using the Musculoskeletal Tumour Society (MSTS) scoring system.ResultsIntercalary allograft reconstruction of femoral shaft, tibial shaft, and distal tibia with ankle arthrodesis was performed in eight, four, and five patients, respectively. Two patients had local recurrence and underwent amputation; one died of metastasis. Host–donor junctions in two patients showed nonunion; 12 patients achieved bone union. The average union time was 12.1 months. No allograft fracture or infection occurred. Union rates were 100% and 88.2% at metaphyseal and diaphyseal junctions, respectively. Healing time differed significantly between the precisely and roughly matched groups (p<0.01). The incidence of nonunion was higher after intramedullary nailing than after the other two methods (p<0.05). The mean MSTS score was 24.2 (14–29) at the end of follow-up.ConclusionIntercalary allograft transplantation is an effective strategy for diaphyseal defect following post-tumor resection in the lower extremity. Good bone healing after allograft reconstruction is achieved with stable internal fixation and perfectly matched host–donor interfaces.

Survival and complications in hinged knee reconstruction prostheses after distal femoral or proximal tibial tumor resection: A retrospective study of 161 cases

IntroductionHinged knee megaprostheses are mainly used for reconstruction after tumor resection. They may incur complications, but this has not been assessed in the French literature, except in small series at short follow-up. We therefore conducted a large-scale nationwide multicenter retrospective study with a minimum 5 years’ follow-up. The objectives were (1) to compare survival between distal femoral and proximal tibial reconstruction prostheses, and (2) to analyze complications and failure. HypothesisDistal femoral hinged reconstruction prostheses show longer survival with fewer complications than proximal tibial prostheses. Material and methodsOne hundred sixty-one patients were included: 118 in the distal femoral group, and 43 in the proximal tibial group. Tumors were mostly osteosarcomas (90 cases) or chondrosarcomas (31 cases). Mean age was 37 years (range, 12-86 years). Complications were assessed on the Henderson classification. Failure was defined by prosthesis anchor exchange or amputation. ResultsAt a mean 9 years’ follow-up (range, 5-23 years), implant survival was longer in the distal femoral group: 5- and 10-year survival, 84% [95% CI, 75-89] and 70% [95% CI, 59-79] versus 74% [95% CI, 69-85] and 43% [95% CI, 23-61] (p=0.02). Revision surgery for complications mainly concerned aseptic loosening (19%, 30 cases) or deep infection (16%, 25 cases) and more often involved the proximal tibia (65% vs. 43%, 28 vs. 51 cases; OR 2.4 [95% CI, 1.2-5.1]; p=0.02). DiscussionHinged knee reconstruction prosthesis is a solution in tumoral pathology, but with a high risk of complications (loosening and infection) and a higher failure rate in the proximal tibial reconstruction prosthesis. Level of evidenceIV, case series.

Long-Term Clinical Outcomes of Intercalary Allograft Reconstruction for Lower-Extremity Bone Tumors.

Improved survival rates for patients with primary bone tumors of the extremities have increased the demand for reliable and durable reconstruction techniques. Some authors have stated that, after successful ingrowth, allografts are a durable long-term solution. This hypothesis is largely based on small studies with short-to-midterm follow-up. In order to determine the durability of intercalary allograft reconstructions in the lower extremities, we evaluated the long-term clinical outcomes at a minimum of 10 years. All patients who received an intercalary allograft reconstruction in a lower extremity between 1980 and 2006 were included in this retrospective multicenter cohort study. One hundred and thirty-one patients with a median age of 19 years were included. Eighty-nine (68%) had a femoral reconstruction, and 42 (32%) had a tibial reconstruction. The most prevalent diagnoses were osteosarcoma (55%), Ewing sarcoma (17%), and chondrosarcoma (12%). The median follow-up was 14 years. A competing risk model was employed to estimate the cumulative incidences of mechanical failure and infection. Patient mortality or progression of the disease was used as a competing event. Nonunion occurred in 21 reconstructions (16%), after a median of 16 months, and was associated with intramedullary nail-only fixation (p < 0.01) and fixation with nonbridging plate(s) (p = 0.03). Allograft fracture occurred in 25 reconstructions (19%) after a median of 42 months (range, 4 days to 21.9 years). Thirteen (52%) of the allograft fractures occurred within 5 years; 8 (32%), between 5 and 10 years; and 4 (16%), at >10 years. With failure for mechanical reasons as the end point, the cumulative incidences of reconstruction failure at 5, 10, and 15 years were 9%, 14%, and 21%, respectively. Intercalary allograft reconstruction is an acceptable reconstructive option, mainly because of the absence of superior alternatives with a known track record. However, a considerable and continuing risk of mechanical complications should be taken into account. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Photobiomodulation Therapy Associated with Heterologous Fibrin Biopolymer and Bovine Bone Matrix Helps to Reconstruct Long Bones.

Bone defects cause aesthetic and functional changes that affect the social, economic and especially the emotional life of human beings. This complication stimulates the scientific community to investigate strategies aimed at improving bone reconstruction processes using complementary therapies. Photobiomodulation therapy (PBMT) and the use of new biomaterials, including heterologous fibrin biopolymer (HFB), are included in this challenge. The objective of the present study was to evaluate the influence of photobiomodulation therapy on bone tibial reconstruction of rats with biomaterial consisting of lyophilized bovine bone matrix (BM) associated or not with heterologous fibrin biopolymer. Thirty male rats were randomly separated into three groups of 10 animals. In all animals, after the anesthetic procedure, a noncritical tibial defect of 2 mm was performed. The groups received the following treatments: Group 1: BM + PBMT, Group 2: BM + HFB and Group 3: BM + HFB + PBMT. The animals from Groups 1 and 3 were submitted to PBMT in the immediate postoperative period and every 48 h until the day of euthanasia that occurred at 14 and 42 days. Analyses by computed microtomography (µCT) and histomorphometry showed statistical difference in the percentage of bone formation between Groups 3 (BM + HB + PBMT) and 2 (BM + HFB) (26.4% ± 1.03% and 20.0% ± 1.87%, respectively) at 14 days and at 42 days (38.2% ± 1.59% and 31.6% ± 1.33%, respectively), and at 42 days there was presence of bone with mature characteristics and organized connective tissue. The µCT demonstrated BM particles filling the defect and the deposition of new bone in the superficial region, especially in the ruptured cortical. It was concluded that the association of PBMT with HFB and BM has the potential to assist in the process of reconstructing bone defects in the tibia of rats.

Giant Cell Tumor of the Distal Tibiofibular Joint: Extensive Curettage, Reconstruction, and Arthrodesis Using Induced Membrane Technique

Masquelet technique may be used successfully for the reconstruction and arthrodesis of distal tibiofibular joint after tumor resection. Giant cell tumors (GCTs) involving both distal tibia and fibula are exceedingly rare. The optimal surgical treatment in these locations is controversial. Reconstruction of cavitary bone loss after resection is challenging. We describe an unusual presentation of exophytic GCT affecting distal tibiofibular joint in a 35-year-old man. The optimal surgical treatment was controversial. Collapse of the tibial plafond was the major risk of surgical resection. An extensive intralesional curettage was performed. The size of the resulting bone defect measured 5 cm in fibula and 4 cm × 3 cm × 2 cm (24 cm 3 ) in tibia. Reconstruction of the cavitary bone loss was challenging. Induced membrane technique was performed for the reconstruction of both tibia and fibula. A plate and a cement spacer were used in the first-time procedure. Two months later, the induced membrane was opened longitudinally. The cement spacer was removed and the biological space which had been created was filled with cancellous bone graft obtained from the patient's iliac crest. Two K-wires were placed in order to avoid tibial plafond collapse and were removed after 6 weeks. Bone union was obtained at 2 months. No recurrence or septic complications were observed. Good functional and anatomic results were obtained at 4 years’ follow-up. Reconstruction and arthrodesis of the distal tibiofibular joint represent an excellent indication of Masquelet technique, especially after GCT resection. The present case highlights therapeutic difficulties in this exceptional location, particularly regarding cavitary bone loss. Mahjoub S, Mihoubi M, Zaraa M, et al. Giant Cell Tumor of the Distal Tibiofibular Joint: Extensive Curettage, Reconstruction, and Arthrodesis Using Induced Membrane Technique. J Foot Ankle Surg (Asia Pacific) 2020;7(1):24–27.

Proximal Tibial Reconstruction After Tumor Resection: A Systematic Review of the Literature.

The proximal part of the tibia is a common location for primary bone tumors, and many options for reconstruction exist following resection. This anatomic location has a notoriously high complication rate, and each available reconstruction method is associated with unique risks and benefits. The most commonly utilized implants are metallic endoprostheses, osteoarticular allografts, and allograft-prosthesis composites. There is a current lack of data comparing the outcomes of these reconstructive techniques in the literature. A systematic review of peer-reviewed observational studies evaluating outcomes after proximal tibial reconstruction was conducted, including both aggregate and pooled data sets and utilizing a Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) review for quality assessment. Henderson complications, amputation rates, implant survival, and functional outcomes were evaluated. A total of 1,643 patients were identified from 29 studies, including 1,402 patients who underwent reconstruction with metallic endoprostheses, 183 patients who underwent reconstruction with osteoarticular allografts, and 58 patients who underwent with reconstruction with allograft-prosthesis composites. The mean follow-up times were 83.5 months (range, 37.3 to 176 months) for the metallic endoprosthesis group, 109.4 months (range, 49 to 234 months) for the osteoarticular allograft group, and 88.8 months (range, 49 to 128 months) for the allograft-prosthesis composite reconstruction group. The mean patient age per study ranged from 13.5 to 50 years. Patients with metallic endoprostheses had the lowest rates of Henderson Type-1 complications (5.1%; p < 0.001), Type-3 complications (10.3%; p < 0.001), and Type-5 complications (5.8%; p < 0.001), whereas, on aggregate data analysis, patients with an osteoarticular allograft had the lowest rates of Type-2 complications (2.1%; p < 0.001) and patients with an allograft-prosthesis composite had the lowest rates of Type-4 complications (10.2%; p < 0.001). The Musculoskeletal Tumor Society (MSTS) scores were highest in patients with an osteoarticular allograft (26.8 points; p < 0.001). Pooled data analysis showed that patients with a metallic endoprosthesis had the lowest rates of sustaining any Henderson complication (23.1%; p = 0.009) and the highest implant survival rates (92.3%), and patients with an osteoarticular allograft had the lowest implant survival rates at 10 years (60.5%; p = 0.014). Osteoarticular allograft appears to lead to higher rates of Henderson complications and amputation rates when compared with metallic endoprostheses. However, functional outcomes may be higher in patients with osteoarticular allograft. Further work is needed using higher-powered randomized controlled trials to definitively determine the superiority of one reconstructive option over another. In the absence of such high-powered evidence, we encourage individual surgeons to choose reconstructive options based on personal experience and expertise. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Novel 3D-printed prosthetic composite for reconstruction of massive bone defects in lower extremities after malignant tumor resection

ObjectiveTo introduce a novel 3D-printed prosthetic composite for reconstruction of massive bone defects after resection for bone malignancy of lower extremities. The design concept, surgical technique, and the preliminary outcomes were elaborated. MethodsPatients with primary malignant tumors of lower extremities requiring tumor resection and reconstruction were recruited between Jun 2015 and Nov 2018. Patient-specific 3D-printed prostheses were designed according to preoperative imaging data. After tumor resection, reconstruction was performed with composites consisting of 3D- printed prosthesis, beta-tricalcium phosphate (β-TCP) bioceramics and/or vascularized fibula. All patients underwent regular follow-up postoperatively. The functional outcomes were assessed by the Musculoskeletal Tumor Society score (MSTS). Oncological outcomes, imaging results, and complications were recorded and analyzed. ResultsTen cases averaging 12.90 years of age participated in this study. There were five femur and five tibia reconstructions. The mean follow-up period was 16.90 months. At last follow-up, all patients were alive without tumor recurrence. Average MSTS functional score was 80.33 ± 11.05%. All prostheses were intact and stable without failure or systemic breakage. No serious complications occurred after the operation. Postoperative X-ray, computed tomography (CT) and single-photon emission computed tomography (SPECT) showed an ideal integration between the bone and the prosthetic composite. Moreover, vascularized fibula and implanted β-TCP bioceramics indicated relatively high metabolic activity in vivo. ConclusionsPatient-specific 3D-printed prostheses combined with β-TCP bioceramics and/or vascularized fibula provide an excellent option for reconstruction of massive bone defects after lower extremity malignant tumor extirpation. Short-term follow up showed promising clinical results in recovering lower limb function, promoting osseointegration and reducing complications.

A Case Report: Custom Made Porous Titanium Implants in Revision: A New Option for Complex Issues

Background: Bone loss management is considered one of the most difficult challenges for orthopaedic surgeon. In massive bone defects, few surgical options are available and they do not offer a reliable or optimal solution for knee reconstruction. Objective: The aim of this paper is to present and justify a new custom-made approach for complex metadiaphyseal bone defects management in knee revision surgery. Methods: We report a case of a 66-year-old woman who underwent a staged left total knee arthroplasty revision for infection with Anderson Orthopaedic Research Institute classification III uncontained femoral and tibial metadiaphyseal bone defects following five prior surgeries. Along with a case discussion, we describe clinical and radiological outcomes of 3 similar patients treated with this new custom-made device. Results: To manage these problems, we developed new, custom porous titanium devices for both femoral and tibial reconstruction tailored to a patient’s specific bone loss. Since, 2014, we treated four cases using custom-made porous titanium cones and we had optimal clinical and radiological results, with no instances of loosening, component migration, or mismatches between preoperative planning and intraoperative findings. Conclusion: In extremely selected cases, this new device can be considered a possible and viable surgical step between “off the shelf” reconstruction implants and knee substitution with a tumor megaprosthesis.

What Kinds of Posterior Cruciate Ligament Bundles Are Preserved in Cruciate-Retaining Total Knee Arthroplasty? A Three-Dimensional Morphology Study.

In this study, the effects of tibial bone cutting on the attachment area of the posterior cruciate ligament (PCL), including both the anterolateral bundle (ALB) and posteromedial bundle (PMB), in cruciate-retaining total knee arthroplasty (CR-TKA) were simulated using a three-dimensional (3D) model of the tibial reconstruction. A total of 40 knees with medial osteoarthritis in patients scheduled for TKA were evaluated. Following surface registration of 3D computed tomography (CT) and 3D magnetic resonance imaging (MRI) models of the tibia with the PCL, the area of PCL attachment was calculated. Tibial bone cutting in the 3D CT model was simulated at 8 and 10 mm distal to the center of the lateral articular surfaces of the tibia and with posterior tibial slope angles of 0, 7, and 10 degrees. The percentages of the ALB and PMB tibial attachment areas that remained after cutting at 8 mm were, respectively, 21.8 ± 19.7% and 86.3 ± 17.7% with 0 degrees, 9.5 ± 10.4% and 64.1 ± 23.6% with 7 degrees, and 8.1 ± 6.7% and 51 ± 25.3% with 10 degrees. These results suggest that only half of the PCL attachment area was left after the bone cut simulation. Complete preservation of the ALB and PMB attachment areas requires appropriate selection of surgical procedures and devices.