The iliac stemmed cup in reconstruction of the acetabular defects secondary to tumor resection: a systematic review of literature.

INTRODUCTION: Stemmed acetabular cups are suitable for reconstruction in case of important bone loss. Nevertheless, their use is not so common, because generally judged very invasive and technically difficult to implant. The aim of the present review is to verify the results of their use and to evaluate indications and complications. MATERIALS AND METHODS: Literature research was performed in the main healthcare databases; indications, surgical technique, related complications, functional results and implant survival were valued and analyzed for every selected paper. RESULTS: 13 studies were selected, for a population of 424 patients and 428 hips. The main indication was reconstruction after tumor removal; the primary non-oncologic indication was revision for aseptic loosening. The most frequent complications were aseptic loosening and implant failure (16.2%), followed by deep infection (11.3%) and dislocation (9.8%). The average MSTS score was 65.9%; while data regarding functional results for degenerative cases are quite fragmented. The 5-years implant survival was 73.6%. CONCLUSIONS: Data regarding SAC prostheses are quite rare in the literature; no prospective studies with comparisons with other reconstruction techniques are available so their use is mainly based on the experience of single centers. While data for tumors are more consistent and supported by studies, information on revisions of hip prosthesis implanted for degenerative problems is quite scarce. Preliminary results on the SAC prosthesis as a valid alternative both for tumoral and degenerative revision cases are encouraging. Prospective randomized studies are advocated to value results compared to alternative techniques.

Custom Massive Allograft in a Case of Pelvic Bone Tumour: Simulation of Processing with Computerised Numerical Control vs. Robotic Machining.

The use of massive bone allografts after the resection of bone tumours is still a challenging process. However, to overcome some issues related to the processing procedures and guarantee the best three-dimensional matching between donor and recipient, some tissue banks have developed a virtual tissue database based on the scanning of the available allografts for using their 3D shape during virtual surgical planning (VSP) procedures. To promote the use of future VSP bone-shaping protocols useful for machining applications within a cleanroom environment, in our work, we simulate a massive bone allograft machining with two different machines: a four-axes (computer numerical control, CNC) vs. a five-axes (robot) milling machine. The allograft design was based on a real case of allograft reconstruction after pelvic tumour resection and obtained with 3D Slicer and Rhinoceros software. Machining simulations were performed with RhinoCAM and graphically and mathematically analysed with CloudCompare and R, respectively. In this case, the geometrical differences of the allograft design are not clinically relevant; however, the mathematical analysis showed that the robot performed better than the four-axes machine. The proof-of-concept presented here paves the way towards massive bone allograft cleanroom machining. Nevertheless, further studies, such as the simulation of different types of allografts and real machining on massive bone allografts, are needed.

Osteoblastoma: When the Treatment Is Not Minimally Invasive, an Overview.

BACKGROUND: osteoblastoma is a bone-forming tumor accounting for about 1% of all primary bone tumors and 3% of benign bone tumors. The gold-standard treatment is surgical excision; nevertheless, minimally invasive radiological techniques such as thermoablation and, more recently, high intensity focused ultrasound are gaining more importance. The aim of the present paper is to analyze surgical indications based on our experience and on the evidences in the literature. METHODS: all patients affected by osteoblastoma who underwent surgical excision in January 2009 and December 2018 were reviewed; eleven patients were enrolled in the study. The epidemiological aspects, size of the disease and site of onset, symptoms, surgery type, indications, and results are reported for every case. RESULTS: all treatments were based on a preoperative diagnosis; pain was constant in all cases. Intralesional surgeries were performed in 9 out of 11 cases; the remaining 2 cases underwent wide resection. No early or late complications occurred after the surgical procedure. The indications for surgery were lesions very close to nerves or joints, unclear diagnosis, risk of fracture, lesion too large for radiofrequency thermoablation, or failure of minimally invasive treatments. At a medium follow-up of 88 months, no local recurrences were verified. CONCLUSIONS: osteoblastoma is a rare tumor with difficult diagnosis. Identification is based on symptoms, imaging, and histology. When possible, minimally invasive techniques is preferred for treatment but surgery is still considered the gold standard.

The role of minimally invasive plate osteosynthesis (MIPO) technique for treating 3- and 4-part proximal humerus fractures in the elderly - a case study.

Background and aim of the work Proximal humeral fractures incidence in the elderly population is increasing. Treatment management is complicated by fracture complexity and patients' comorbidities. The aim of our prospective study is the outcome evaluation of the role of minimally invasive plate osteosynthesis (MIPO) for elderly patients with a 3- or 4-parts proximal humeral fractures having an intact medial wall.   Methods We included n=42 unilateral 3- and 4-parts proximal humeral fractures treated with MIPO: 20 4-part fractures and 22 were 3-parts fractures were included. 17 patients identified as male and 25 as female (mean age 84yo).  A trans-deltoid approach has been used with minimal surgical exposure and tissue damage to preserve the local tissue for early shoulder mobilization.   Results At follow-up, the DASH recorded mean value was 72, while the Constant mean score was 68. Complications have been recorded in 23,8% of patients with 4-parts fractures having the highest complication frequency. Mean shoulder joint ROM was recorded: anterior elevation 75°, lateral elevation 80°, abduction 90°, intra-rotation 50°, extra-rotation 25°. The following factors were identified influencing the outcome: >8mm calcar fragment, head valgus impaction and periosteal medial hinge preservation.   Conclusions The increase in population longevity matches the increase in complex humeral fracture frequency. We strongly for management consensus for proximal humerus fracture, in a similar way as for neck femoral fractures. MIPO is excellent in reducing soft tissue damage and complications for elderly patients with limited functional demand.

3D-Printed Titanium Custom-Made Prostheses in Reconstruction after Pelvic Tumor Resection: Indications and Results in a Series of 14 Patients at 42 Months of Average Follow-Up.

Wide resection is currently considered the mainstay treatment for primary bone tumors. When the tumor is located in anatomically complex segments, 3D-Printed Titanium Custom-Made Prostheses (3DPTCMP) are possible reconstructive solutions. The aim of the present paper is to analyze indications, results and complications of a series of 14 patients who underwent pelvis reconstruction with 3DPTCMP after tumor removal from January 2015 to December 2019. Chondrosarcoma was the main histology; indications were tumors located in the acetabular area without enough residual bone to support a cup with an iliac stem, and tumors located near the sacrum-iliac joint. The margins were wide in 12 cases, and marginal and intralesional in one case each. In three cases, resection also included the sacrum-iliac joint, so a spine stabilization was performed and linked to the pelvic prosthesis; The average MSTS score was 46.3%; the 5-year local recurrence-free survival was 85.7%. Wound dehiscences were the main complication, resolved with multiple debridements; nevertheless, prosthesis removal was necessary in one case. Currently, the 3DPTCMP is an effective resource for reconstruction after resection of tumors located in the pelvis. Further studies are necessary to value long-term results; more strategies are necessary to try to reduce the infection rate and improve osteointegration.

A New Proximal Femur Reconstruction Technique after Bone Tumor Resection in a Very Small Patient: An Exemplificative Case.

For patients too young to be fitted with an expandable prosthesis, limb salvage surgery requires other strategies. The main problems are related to the impossibility of implanting an expandable prosthesis to the residual bone growth that is much too big in relation to the bone size, with the precocious implant loosening and/or the residual absence of bone growth, as well as the problem of limb length and shape difference. In this paper, we report a possible reconstruction solution using a composite prosthesis for an Ewing's sarcoma of the proximal femur in an infant patient. After resection, a femoral stem was cemented into the distal third of a homoplastic humerus; a carbon fiber plate was used to stabilize the bone/homograft interface. At the one-year follow-up, the patient was free of disease and able to walk with only a slight limp. This case report describes a possible solution for very small patients. An adult humerus is of the right size to replace a child's lower limb segments, and the distal humerus can be shaped, maintaining a cortex stiff enough to support a prosthesis. Very young patients might obtain a faster osteointegration of the graft than adults, due to their higher biological activity and, in this case, the diapasonal shape of the allograft might also have contributed to accelerated fusion. Moreover, the use of a graft to fit the prosthesis avoids loosening issues due to canal widening, hypothetically providing more growing time before system failure and revision surgery. However, although this technique is promising, further studies are necessary to confirm our findings and to verify if this procedure allows easier future prosthesis implantation.

The IlluminOss® photodynamic bone stabilization system for pathological osteolyses and fractures of the humerus: indications, advantages and limits in a series of 12 patients at 24 months of minimum follow-up.

BACKGROUND: Locked titanium nails are considered the reference treatment for metastatic bone lesions of the humerus in patients with aggressive histotypes, high risk of fracture or when estimated survival is lower than 6 months.Nevertheless, they are responsible for CT and MRI artifacts which interfere with postoperative radiotherapy and follow-up.The IlluminOss® is an intramedullary stabilization system which is introduced inside the humeral canal in a deflated state, and is then distended with a monomer which hardens after exposure to blue light,stabilizing the segment; it does not cause artifacts, allowing easier and more effective radiotherapy and follow-up. The aim of this study is to report our experience, indications, possible advantages and limitations of this stabilization system at 24 months of minimum follow-up in a series of 12 patients affected by pathological fractures or impending fractures of the humerus. METHODS: This is a retrospective case-series that included all patients who underwent surgery with the IlluminOss® Photodynamic Bone Stabilization System for pathological osteolyses and fractures of the humerus. Intraoperative and postoperative complications were valued. RESULTS: 12 patients and 13 procedures were included in the study. All surgeries were performed without intraoperative complications. No early postoperative complications were noted. The wounds healed in all cases and stitches were removed at two weeks from surgery, so the patients were able to perform chemotherapy after three weeks. All patients except one had a painless active range of motion which reached 90°.The VAS score was 7 preoperatively and 2.6 at one month from surgery. Pain relief was also associated to radiotherapy and chemotherapy. Unfortunately, two nail ruptures were reported at 4 and 12 months of follow-up. No artifacts were noted in the postoperative CT scans so the radiotherapy plans were easily performed without the need of dose compensation. CONCLUSIONS: The IlluminOss® intramedullary stabilization system can provide primary stability in humeral fractures and impending fractures;the surgical technique is easy and minimally invasive.Moreover,it does not present artifacts at postoperative imaging,probably giving a better chance to perform prompt radiotherapy and chemotherapy.However, randomized clinical studies are necessary to verify its potential strength and if precocious adjuvant radio- and chemotherapy are associated to a reduction of the local progression rate.

Fibrous dysplasia: an unusual case of a very aggressive form with costo-vertebral joint destruction and invasion of the contralateral D7 vertebral body.

Fibrous dysplasia (FD) is a benign fibro-osseous disease of the bone that may be solitary or multicentric. It is important to distinguish this type of lesion from low-grade osteosarcomas (LGOS) and from secondary sarcomas, because malignant transformation has rarely been reported. It is classically described as having a ground-glass appearance, endosteal scalloping, and thinning of the cortex. Cortical disruption is considered evidence of malignancy, but it can also be present in benign FD with aggressive behavior. We present an unusual case of aggressive FD of the 7th left rib, already diagnosed more than 22 years ago, where cortical and costo-vertebral joint disruption and 7th thoracic vertebral body involvement were not evidence of malignant behavior. From a histological perspective, FD and LGOS are similar; even if histology is of fundamental importance, the diagnosis has to be made based on the clinical and radiological aspects as well, although at imaging, differentiation between FD and LGOS can be difficult. In the present case, even though the histological examination suggested a benign lesion, the radiological examination instead consistently suggests malignancy. It is for this reason that there should be a high index of suspicion during follow-up and a new biopsy should be scheduled in case any changes occur during follow-up.

Intralesional vs. extralesional procedures for low-grade central chondrosarcoma: a systematic review of the literature.

INTRODUCTION: Chondroid lesions are very common bone tumors. In most cases, they are benign enchondromas (EC) and, in a minor percentage, chondrosarcomas (CSs), the malignant counterpart. In the latter cases, surgery is the mainstay treatment, because they are chemo- and radio-resistant unless dedifferentiation occurs. If resection is recognized as the gold standard for intermediate-, high-grade tumors, and for low-grade chondrosarcoma (LG-CS) located in the spine and pelvis to reduce the risk of local recurrence, there is still no consensus in literature on the treatment of central low-grade chondrosarcoma (cLG-CS) located in the limbs. Our aim is to perform a review of literature on evidence supporting this approach or not. MATERIALS AND METHODS: An electronic research of the medical archives was carried out in March 2017 seeking papers evaluating the results of curettage and resection in cLG-CS. RESULTS: We selected 13 studies corresponding to our criteria. Unfortunately, they were descriptive, retrospective, non-randomized studies. We identified a population of 471 patients for a total of 473 low-grade chondrosarcomas. Two hundred and ninety-nine lesions were treated with curettage and 174 with wide surgery. The two groups were not homogeneous for diagnosis, size and staging, so no comparison between resection and curettage was possible. The global weighted average percentage of local recurrence was 6.7% (20 cases) and 10.9% (19 cases) after curettage and resection, respectively. No cases of metastasis were reported in the group treated with intralesional surgery, compared to five cases reported in the group treated with resection. Indications for surgery were given in most cases based on symptoms and imaging. CONCLUSIONS: The absence of a preoperative histological diagnosis and the lack of a scientific method to conduct the studies do not sufficiently support curettage for low-grade chondrosarcomas. In the absence of this, resection must be considered a general rule for every malignancy. In our opinion, based on the low biological growth rate of low-grade chondrosarcoma, every chondromatous lesion can be followed-up. Biopsies must be performed based on clinical and radiological suspicions such as pain, scalloping or increase in size, rather than on performing a PET scan to evidence more informative high metabolic areas.

The dual mobility cup in muscular skeletal oncology: rationale and indications.

PURPOSE: Because of the improvement of medical therapy and the corresponding increase in life expectancy, orthopaedic surgeons are obliged to perform more wide resections rather than intramedullary stabilization nailing for patients affected by tumours of the hip compared to the past. Wide resection often causes joint instability, so prosthetic reconstruction presents a higher risk of dislocation than in primary osteoarthritis cases. The aim of the present paper is to classify the indications for the dual mobility cup (DMC) hip prosthesis based on the anatomic structures involved in the disease and to analyse the rationale to reduce the risk of dislocation. METHODS: Indications were analyzed and classified based on all the cases in which the DMC prosthesis was used for reconstruction after hip resection in an oncological research hospital. RESULTS: Four classes of indications were identified; for classes I and IV the indication for DMC prosthesis can be considered strong; for classes II and III the indications must be evaluated considering the specific case, based on life expectancy, performance status, presence of osteoarthritis, and availability of adjuvant local therapies. When the DMC prosthesis is indicated, the cup should always be cemented, either alone or with augmentation techniques, to decrease the risk of mobilization due to local disease progression. CONCLUSIONS: DMC can be a valid alternative in reconstruction of the hip after tumor removal; nevertheless, prospective, randomized studies are necessary to verify the real dislocation rate based on the entity of resection.

Risk analysis in tibial plateau fractures: association between severity, treatment and clinical outcome.

Our retrospective study analyzes efficacy of treatment techniques we used for the reduction of tibial plateau fracture. A sample of 67 individuals is evaluated, 50 males and 17 females, and treated for a tibial plateau fracture from December 2003 to June 2008. The mean age is 46 (range 22-72). 35 patients were treated with cannulated screws alone, 21 were treated with plates alone, and 11 were treated with both plates and bone substitutes. All patients were clinically and radiographically followed up for an average time of 36.4 months (SD = 17.4; range 24-72). Data about patients sourced from the analysis of SF36, WOMAC and the Rasmussen score. Patients were divided into 4 groups and 2 subgroups, according to the synthesis method used and the severity of the fracture. The control group includes the patients diagnosed with a low-energy fracture treated with screws alone. The median of the total score of Rasmussen functional grading system resulted to be equal to 26; compared with the control group, there is strong relationship between the use of plates alone and the risk of obtaining a clinically less effective result (O.R. = 5.48; p = 0.003) even more when comparing Schatzker type IV, V, and VI (O.R. = 13; p = 0.0073). Radiographic evaluation shows less efficacy of bone substitute to reduce articular step-off. With regard to the SF36, patients treated with plate alone have been awarded the lowest score. The treatment of the most severe fractures of tibial plateau by means of internal fixation with plates can be improved with the use of bone substitutes.