• 3D model
• 3D printing
• pediatric limb deformities
• pediatric orthopedic oncology
• pediatric spinal deformities

• Chondrosarcoma
• Cutting guides
• Ewing’s sarcoma
• Osteosarcoma
• Patient-specific instrumentation
• Pelvic tumours

• Humans
• Male
• Osteosarcoma/surgery
• Osteosarcoma/diagnostic imaging
• Osteosarcoma/secondary
• Ilium/surgery
• Ilium/diagnostic imaging
• Ilium/pathology
• Adolescent
• Bone Neoplasms/surgery
• Bone Neoplasms/pathology
• Bone Neoplasms/diagnostic imaging
• Plastic Surgery Procedures/methods
• Printing, Three-Dimensional
• Osteotomy/methods

• 3D printing
• Patient-specific instrument
• Pelvis
• Primary malignant bone tumor

• Humans
• Female
• Male
• Retrospective Studies
• Middle Aged
• Margins of Excision
• Bone Neoplasms/surgery
• Bone Neoplasms/pathology
• Adult
• Neoplasm Recurrence, Local/surgery
• Neoplasm Recurrence, Local/pathology
• Aged
• Follow-Up Studies
• Prognosis
• Pelvic Bones/surgery
• Pelvic Bones/pathology
• Young Adult
• Osteotomy/methods
• Surgery, Computer-Assisted/methods
• Pelvic Neoplasms/surgery
• Pelvic Neoplasms/pathology
• Adolescent

• Adult
• Female
• Humans
• Male
• Middle Aged
• Allografts
• Bone Neoplasms/surgery
• Bone Transplantation/methods
• Femoral Neoplasms/surgery
• Femur/surgery
• Osteosarcoma/surgery
• Plastic Surgery Procedures/methods
• Printing, Three-Dimensional
• Treatment Outcome

• Università degli Studi di Padova

• 3D printed patient-specific instrument
• Accuracy
• Bone tumor
• Joint-preserving surgery

• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• RDY2022-01 Peking University People's Hospital Scientific Research Development Funds
• Peking University People’s Hospital Scientific Research Development Funds

• Humans
• Margins of Excision
• Sarcoma/surgery
• Soft Tissue Neoplasms/surgery
• Cell Proliferation
• Combined Modality Therapy

• bone sarcoma
• pelvic defects
• pelvic reconstruction
• three dimensional printing

• Humans
• Prostheses and Implants
• Pelvis/surgery
• Acetabulum/surgery
• Orthopedic Procedures
• Printing, Three-Dimensional

• 3D printing
• Cavovarus deformity
• Cavus
• Cutting guides
• Osteotomy
• Patient-specific

• Humans
• Reproducibility of Results
• Foot
• Arthrodesis/methods
• Osteotomy/methods

• 3D-Cutting guides
• Bone tumors
• Margins
• Osteosarcoma
• Patient specific instrumentation
• Sarcoma
• Surgical navigation

• Bone tumours
• Orthopaedic oncology
• Patient-specific implants
• Robotic surgery
• Surgical robotics

• Male
• Animals
• Sheep
• Robotics
• Orthopedics
• Surgery, Computer-Assisted/methods
• Tomography, X-Ray Computed
• Femur/diagnostic imaging
• Femur/surgery
• Dental Implants

• IMCRC/STR/18092017 Innovative Manufacturing CRC
• Royal Melbourne Institute of Technology

• Sarcoma
• bone
• pelvis
• surgery
• treatment

• Humans
• Sarcoma, Ewing/diagnosis
• Sarcoma, Ewing/surgery
• Bone Neoplasms/diagnosis
• Bone Neoplasms/surgery
• Prognosis
• Sarcoma/diagnosis
• Sarcoma/surgery
• Osteosarcoma/diagnosis
• Osteosarcoma/surgery
• Pelvic Bones/surgery
• Pelvis/pathology
• Soft Tissue Neoplasms

• 3D printing
• Osteotomy guide
• Patient-specific instrument
• Spine
• Spine metastasis
• Spine navigation
• Spine tumor
• Surgical planning

• 3D CT
• 3D MRI
• 3D printing
• Bone tumour resection
• MR images
• Patient-specific resection guide
• Resection error
• anatomical structures
• bone resection
• bone tumour resections
• bone tumours
• metastatic bone tumours
• osteosarcoma
• soft-tissue

• 3d printing
• augmented reality
• preoperative planning
• virtual reality
• virtual surgical planning

• Humans
• Imaging, Three-Dimensional/methods
• Models, Anatomic
• Printing, Three-Dimensional
• Virtual Reality
• Surgery, Computer-Assisted
• Orthopedic Procedures/methods

• 3D pre-operative planning
• Anatomical models
• Internal hemipelvectomy
• Patient specific instruments (PSI)
• Pelvic bone tumors

• 3D-printing
• Additive manufacturing
• Computer assisted planning
• Corrective osteotomy
• Lower extremity
• Malunion

• Additive manufacturing
• Bone tumor
• Implant
• Limb salvage surgery
• Three-dimensional printing

•

Patient-specific instruments (PSI) improve surgical orthopaedic interventions.

Patient Specific Instruments (PSI) is currently a proven technique for bone tumor resection. In a previous publication, we analyzed the quality of margin resection of pelvic sarcoma resections with the use of PSI (by pathologic evaluation of the margins). In this new study, we compare preoperative resection planning and actual resection margins by MRI analysis of the resection specimens.

Between 2011 and 2020, 31 patients underwent bone tumor resection with the use of PSI. Preoperatively, the margins were planned with a software and PSI were made according to these margins. Postoperatively, the surgical resection specimens were analyzed with MRI. Resection margins were measured with the same software used in the preoperative planning.

All margins were safe (free of tumor). The differences between preoperative planned margins and the obtained ones were within the range −5 to +5 mm. The correlation between planned margin and the obtained one was excellent (R² = 0.841; p < 0.0001).

This study demonstrates the accuracy of PSI. In our series, all resection margins were safe. A minimal 5 mm-margin has to be planned but a larger sample is needed to give recommendations.

Extra-articular resection (EAR) of the hip joint is prone to significant complications and morbidity. Thus, this study evaluates the cumulative incidences and main reasons of reoperation following EAR of primary malignant bone tumors (PMBT) of the hip to determine whether the outcomes are different between EAR of the pelvis and that of the proximal femur.

Thirty-three patients presented with a PMBT of the proximal femur or pelvis were included in this study. Among all PMBTs, 58% originated from the pelvis and 42% were from the proximal femur. Twenty patients had chondrosarcomas (61%), 10 had osteosarcomas (30%), and 3 had sarcomas of another histological subtype (9%).

The mean follow-up was of 76 months (range: 24–220 months). The cumulative probabilities of revision for any reason were 52% (95% confidence interval [CI] 30–70%) 5 years after surgery. The 5-year cumulative probabilities of revision were 13% (95% CI 4–27%), 24% (95% CI 10–42%), and 34% (95% CI 14–56%) for mechanical, infectious, and tumoral reasons, respectively. The 5-year cumulative probabilities of revision for any reason were 78% (95% CI 37–94%) and 14% (95% CI 2–38%) for the pelvis and proximal femur, respectively (p = 0.004). Posterior column preservation was significantly associated with more mechanical complications even after adjusting for the resection site (p = 0.043).

Half of patients undergoing EAR of the hip joint for PMBT of the proximal femur or acetabulum will require another operation. EAR of the pelvis is associated with significantly worse outcome than EAR of the proximal femur.

In orthopaedic oncology, surgical planning and intraoperative execution errors may result in positive tumor resection margins that increase the risk of local recurrence and adversely affect patients’ survival. Computer navigation and 3D-printed resection guides have been reported to address surgical inaccuracy by replicating the surgical plans in complex cases. However, limitations include surgeons’ attention shift from the operative field to view the navigation monitor and expensive navigation facilities in computer navigation surgery. Practical concerns are lacking real-time visual feedback of preoperative images and the lead-time in manufacturing 3D-printed objects. Mixed Reality (MR) is a technology of merging real and virtual worlds to produce new environments with enhanced visualizations, where physical and digital objects coexist and allow users to interact with both in real-time. The unique MR features of enhanced medical images visualization and interaction with holograms allow surgeons real-time and on-demand medical information and remote assistance in their immediate working environment. Early application of MR technology has been reported in surgical procedures. Its role is unclear in orthopaedic oncology. This review aims to provide orthopaedic tumor surgeons with up-to-date knowledge of the emerging MR technology. The paper presents its essential features and clinical workflow, reviews the current literature and potential clinical applications, and discusses the limitations and future development in orthopaedic oncology. The emerging MR technology adds a new dimension to digital assistive tools with a more accessible and less costly alternative in orthopaedic oncology. The MR head-mounted display and hand-free control may achieve clinical point-of-care inside or outside the operating room and improve service efficiency and patient safety. However, lacking an accurate hologram-to-patient matching, an MR platform dedicated to orthopaedic oncology, and clinical results may hinder its wide adoption. Industry-academic partnerships are essential to advance the technology with its clinical role determined through future clinical studies.

Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use:

https://youtu.be/t4hl_Anh_kM

• did not receive

• Patient-specific modeling
• Prostheses and implants
• Sarcoma
• Surgical navigation systems
• Titanium

• Type III + half pelvic resection
• Type I + half pelvic resection
• pelvic tumors

The precise acetabular reconstruction has historically been a challenging procedure. 3D-printed patient-specific guide (PSG) and computer navigation (CN) technologies have been used to assist acetabular component positioning and pelvic reconstruction. This precise reconstruction approach may translate into clinical benefit.

The clinical data of 84 patients who underwent periacetabular malignant tumor resection and screw-rod-acetabular cage system reconstruction in our center from January 2013 to December 2020 were retrospectively analyzed. Patients were divided into four groups: free hand (FH) group, PSG group, CN group, and PSG combined with computer navigation (PSG + CN) group. The operation time, intraoperative blood loss, and number of fluoroscopy views were recorded. The oncological prognosis, radiographic measurements of the acetabulum, limb function data, and postoperative complications were compared among groups. And finally, we evaluated the risk factors for mechanical failure of the prosthesis.

The postoperative X-ray and computed tomography (CT) scan revealed that the vertical offset discrepancy (VOD) between affected side and contralateral side was 8.4±1.9, 5.9±2.2, 4.1±1.3, and 2.4±1.2 mm in each groups; the horizontal offset discrepancy (HOD) was 9.0±1.9, 6.1±2.2, 3.2±1.3, and 2.1±1.2 mm, correspondingly; the abduction angle discrepancy (ABAD) was 8.6°±1.8°, 5.6°±2.0°, 2.5°±1.3°, and 1.8°±0.9°, respectively; the anteversion angle discrepancy (ANAD) was 5.9°±1.6°, 3.6°±1.7°, 2.9°±1.6°, and 1.9°±0.9°, correspondingly. Statistical results show that the PSG + CN group was superior to the FH group and the PSG group in terms of acetabular position and limb function (P<0.05). Body mass index (P=0.040) and resection type (P=0.042) were found to be the high-risk factors for mechanical failure of the prosthesis.

PSG + CN has potential advantages in improving the accuracy and safety of acetabular positioning and reconstruction.

• Guide plate
• acetabular positioning
• hemipelvic reconstruction
• navigation

• 3D printing
• augmented reality
• patient-specific instruments
• pelvic tumor resection

• Augmented Reality
• Humans
• Imaging, Three-Dimensional
• Pelvic Neoplasms
• Pelvis/surgery
• Phantoms, Imaging
• Surgery, Computer-Assisted

• Acetabulum/surgery
• Aged
• Arthroplasty, Replacement
• Carcinoma, Renal Cell/pathology
• Carcinoma, Renal Cell/surgery
• Humans
• Kidney Neoplasms/pathology
• Kidney Neoplasms/surgery
• Male
• Pelvic Neoplasms/surgery

• 3D assisted navigation
• Cadaveric study
• Desktop 3D printing
• Estudio en cadáver
• Impresión 3D
• Instrumentos paciente-específicos
• Navegación asistida por 3D
• Patient-specific instruments
• Pelvic tumor
• Tumores pélvicos

• iliosacral tumor
• limb salvage
• osteotomy
• surgical margin

• 3D printing
• Patient specific instrumentation
• Reverse shoulder arthroplasty

Pelvic osteosarcoma has a poor prognosis compared to osteosarcomas in other locations, and the reasons for this remains unknown. Surgical resection of pelvic osteosarcoma is technically demanding and often results in dysfunction and complications. In this study, we investigated the reasons underlying the poor prognosis of pelvic osteosarcoma by comparing it to femoral osteosarcoma using data from the Bone Tumor Registry in Japan. We used propensity score analysis to determine whether surgical resection of pelvic osteosarcoma improved its prognosis. We demonstrated that pelvic osteosarcoma had a poor prognosis because it occurred more often in the elderly, often had a larger tumor size, and had metastasis at presentation more often in comparison to femoral osteosarcoma. These three factors were also associated with the non-surgical treatment of pelvic osteosarcoma, which also led to a poor outcome. The overall survival rate was only comparable in pelvic osteosarcoma and femoral osteosarcoma in cases treated with surgical resection. Propensity score analysis revealed that surgical treatment improved the prognosis of pelvic osteosarcoma. As such, we propose that surgical resection should be considered based on tumor stage and patient age in order to improve the prognosis of pelvic osteosarcoma.

Pelvic osteosarcoma has a poor prognosis compared to osteosarcomas in other locations, and the reasons for this remain unknown. Surgical resection of pelvic osteosarcoma is technically demanding and often results in dysfunction and complications. In this study, we investigated the reasons underlying the poor prognosis of pelvic osteosarcoma by comparing it to femoral osteosarcoma using data from the Bone Tumor Registry in Japan. We used propensity score analysis to determine whether surgical resection of pelvic osteosarcoma improved its prognosis. We demonstrated that pelvic osteosarcoma had a poor prognosis because it occurred more often in the elderly, often had larger tumor size, and had metastasis at presentation more often in comparison to femoral osteosarcoma. These three factors were also associated with the non-surgical treatment of pelvic osteosarcoma, which also led to a poor outcome. The overall survival rate was only comparable in pelvic osteosarcoma and femoral osteosarcoma in cases treated with surgical resection. Propensity score analysis revealed that surgical treatment improved the prognosis of pelvic osteosarcoma. As such, we propose that surgical resection should be considered based on tumor stage and patient age in order to improve the prognosis of pelvic osteosarcoma.

• pelvic osteosarcoma
• prognosis
• propensity score
• surgical resection

In selected extremity bone sarcomas, joint-preserving surgery retains the natural joints and nearby ligaments with a better function than in traditional joint-sacrificing surgery. Geometric multiplanar osteotomies around bone sarcomas were reported with the advantage of preserving more host bone. However, the complex surgical planning translation to the operating room is challenging.

Using both Computer Navigation and Patient-Specific Guide may combine each technique's key advantage in assisting complex bone tumor resections. Computer Navigation provides the visual image feedback of the pathological information and validates the correct placement of Patient-Specific Guide that enables accurate, guided bone resections. We first described the digital workflow and the use of both computer navigation and patient-specific guides (NAVIG) to assist the multiplanar osteotomies in three extremity bone sarcoma patients who underwent joint-preserving bone tumor resections and reconstruction with patient-specific implants. The NAVIG technique verified the correct placement of patient-specific guides that enabled precise osteotomies and well-fitted patient-specific implants. The mean maximum deviation errors of the nine achieved bone resections were 1.64 ​± ​0.35 ​mm (95% CI 1.29 to 1.99). The histological examination of the tumor specimens showed negative resection margin. At the mean follow-up of 55 months (40–67), no local recurrence was noted. There was no implant loosening that needed revision. The mean MSTS score was 29 (28–30) out of 30 with the mean knee flexion of 140° (130°–150°).

The excellent surgical accuracy and limb function suggested that the NAVIG technique might replicate the surgical planning of complex bone sarcoma resections by combining the strength of both Computer Navigation and Patient-Specific Guide. The patient-specific approach may translate into clinical benefits. The translational potential of this article:

The newly described technique enhances surgeons’ capability in performing complex joint-preserving surgery in bone sarcoma that is difficult to be achieved by the traditional method. The high precision and accuracy may translate into superior clinical outcomes.

• Computer navigation
• Joint-preserving tumor surgery
• Osseointegration
• Patient-specific guide
• Patient-specific implants
• Surgical accuracy

The combination of 3D printing and navigation promises improvements in surgical procedures and outcomes for complex bone tumor resection of the trunk, but its features have rarely been described in the literature. Five patients with trunk tumors were surgically treated in our institution using a combination of 3D printing and navigation. The main process includes segmentation, virtual modeling and build preparation, as well as quality assessment. Tumor resection was performed with navigated instruments. Preoperative planning supported clear margin multiplanar resections with intraoperatively adaptable real-time visualization of navigated instruments. The follow-up ranged from 2–15 months with a good functional result. The present results and the review of the current literature reflect the trend and the diverse applications of 3D printing in the medical field. 3D printing at hospital sites is often not standardized, but regulatory aspects may serve as disincentives. However, 3D printing has an increasing impact on precision medicine, and we are convinced that our process represents a valuable contribution in the context of patient-centered individual care.

• 3D printing
• bone defects
• navigation-assisted surgery
• oncologic orthopedics
• patient specific
• tumor orthopedics
• tumor surgery

• bone tumour
• computer-assisted
• navigation
• pelvis
• sacrum
• sarcoma

• Humans
• Neoplasm Recurrence, Local
• Pelvic Bones/diagnostic imaging
• Pelvic Bones/surgery
• Printing, Three-Dimensional
• Plastic Surgery Procedures
• Retrospective Studies

• Cadaveric study
• Desktop 3D printing
• Patient-specific instruments
• Pelvic tumour

Acetabular fractures pose diagnostic and surgical challenges. They are classified using the Judet-Letournel system, which is based solely on X-ray. However, computed tomography (CT) imaging is now more widely utilized in diagnosing these injuries. The emergence of 3-dimensional (3-D) printing technology in varying orthopedic fields has provided surgeons a solid model that improves their spatial understanding of complex fractures and ability to plan pre-operatively.

To evaluate the reliability of the Judet-Letournel classification system of acetabular fractures, when using either CT imaging or 3-D printed models.

Seven patients with acetabular fractures underwent pelvic CT imaging, which was then used to create solid, 3-D printed models. Eighteen orthopaedic trauma surgeons responded to questionnaires regarding fracture classification and preferred surgical approach. The same questionnaire was completed using only CT imaging, and two weeks later, using only 3-D printed models. The inter- and intra-observer agreement rates were then analyzed.

Inter-observer agreement rates based on CT imaging or 3-D printed models were moderate for fracture classification: κ = 0.44, κ = 0.55, respectively (P < 0.001) and fair for preferred surgical approach: κ = 0.34, κ = 0.29, respectively (P < 0.005). Intra-observer agreement rates for fracture classification and preferred surgical approach comparing CT imaging or 3-D printed models were moderate: κ = 0.48, κ = 0.41, respectively. No significant difference in intra-observer agreement was detected when comparing orthopedic pelvic specialists to general orthopedic traumatologists.

The Judet-Letournel classification demonstrated only moderate rates of agreement. The use of 3-D printed models increased the inter-observer agreement rates with respect to fracture classification, but decreased it with respect to the preferred surgical approach. This study highlights the role of 3-D printed models in acetabular fractures by improving spatial understanding of these complex injuries, thus providing more reliable fracture diagnoses and alternative viewpoints for pre-operative planning.

• Acetabulum
• Pelvic trauma
• Acetabular fracture
• Three-dimensional printing
• Three-dimensional reconstruction
• Judet-Letournel

The long-term outcomes of osteosarcoma have improved; however, patients with metastases, recurrence or axial disease continue to have a poor prognosis. Computer navigation in surgery is becoming ever more commonplace, and the proposed advantages, including precision during surgery, is particularly applicable to the field of orthopaedic oncology and challenging areas such as the axial skeleton. Within this article, we provide an overview of the field of computer navigation and computer-assisted tumour surgery (CATS), in particular its relevance to the surgical management of osteosarcoma.

• computer navigation
• computer-assisted surgery
• osteosarcoma
• patient-specific instrumentation

• Synovial sarcoma
• acetabulum
• hemipelvectomy
• pelvic sarcoma

• 3D printing technology
• Bone reconstruction
• Bone tumour surgery
• Limb salvation
• Patient-specific orthopaedics

• forearm
• image-to-image registration
• mutual information
• surgical planning

• 3D resection
• bone tumor
• limb salvage surgery
• patient-specific instruments
• surgical guide

• computer assisted
• margins of excision
• orthopedic procedures
• patient-specific instruments
• pelvic neoplasms
• surgery

• Adult
• Aged
• Bone Diseases, Infectious/diagnosis
• Bone Diseases, Infectious/pathology
• Bone Diseases, Infectious/surgery
• Bone Substitutes/chemical synthesis
• Bone Substitutes/chemistry
• Bone Substitutes/therapeutic use
• Diaphyses/diagnostic imaging
• Diaphyses/surgery
• Female
• Femoral Fractures/diagnosis
• Femoral Fractures/pathology
• Femoral Fractures/surgery
• Femur/diagnostic imaging
• Femur/pathology
• Femur/surgery
• Humans
• Male
• Middle Aged
• Porosity
• Precision Medicine/instrumentation
• Precision Medicine/methods
• Printing, Three-Dimensional
• Prosthesis Design/methods
• Prosthesis Failure
• Reoperation
• Therapies, Investigational/methods
• Treatment Outcome