Reconstruction of pelvic bone defect after resection for bone tumours is a challenging procedure especially when the hip joint is involved due to the anatomy and the complex biomechanical and structural function of the pelvic ring. This surgery is associated to high complication rate. The additive 3D printing technology allows us to produce trabecular titanium custom based implants with an accurate planning of resection using bone cutting jigs.

From August 2013 to January 2017, we treated 8 patients for bone pelvic sarcoma with custom-made osteotomy jigs (Nylon) and custom-made trabecular titanium prosthesis produced through rapid prototyping technology based on mirroring of the contralateral hemipelvis. Mean follow up time was 18 months (range 2–30) Wide margins were obtained in all cases, in one a local recurrence developed. Surgical time was 4 hours average (from 180 to 250 mins). No postoperative complications were reported.

Rapid prototyping is a promising technique in order to achieve wide surgical margins and restore the anatomy in pelvic bone tumour resection as well as reducing complications.

Objectives. To assess the accuracy of patient-specific instruments (PSIs) versus standard manual technique and the precision of computer-assisted planning and PSI-guided osteotomies in pelvic tumour resection. Methods. CT scans were obtained from five female cadaveric pelvises. Five osteotomies were designed using Mimics software: sacroiliac, biplanar supra-acetabular, two parallel iliopubic and ischial. For cases of the left hemipelvis, PSIs were designed to guide standard oscillating saw osteotomies and later manufactured using 3D printing. Osteotomies were performed using the standard manual technique in cases of the right hemipelvis. Post-resection CT scans were quantitatively analysed. Student’s t-test and Mann–Whitney U test were used. Results. Compared with the manual technique, PSI-guided osteotomies improved accuracy by a mean 9.6 mm (p < 0.008) in the sacroiliac osteotomies, 6.2 mm (p < 0.008) and 5.8 mm (p < 0.032) in the biplanar supra-acetabular, 3 mm (p < 0.016) in the ischial and 2.2 mm (p < 0.032) and 2.6 mm (p < 0.008) in the parallel iliopubic osteotomies, with a mean linear deviation of 4.9 mm (p < 0.001) for all osteotomies. Of the manual osteotomies, 53% (n = 16) had a linear deviation > 5 mm and 27% (n = 8) were > 10 mm. In the PSI cases, deviations were 10% (n = 3) and 0 % (n = 0), respectively. For angular deviation from pre-operative plans, we observed a mean improvement of 7.06° (p < 0.001) in pitch and 2.94° (p < 0.001) in roll, comparing PSI and the standard manual technique. Conclusion. In an experimental study, computer-assisted planning and PSIs improved accuracy in pelvic tumour resections, bringing osteotomy results closer to the parameters set in pre-operative planning, as compared with standard manual techniques. Cite this article: A. Sallent, M. Vicente, M. M. Reverté, A. Lopez, A. Rodríguez-Baeza, M. Pérez-Domínguez, R. Velez. How 3D patient-specific instruments improve accuracy of pelvic bone tumour resection in a cadaveric study. Bone Joint Res 2017;6:577–583. DOI: 10.1302/2046-3758.610.BJR-2017-0094.R1

Abstract. Background. Conventional periacetabular pelvic resections are associated with poor functional outcomes. Resections through surgical corridors beyond the conventional margins may be helpful in retaining greater function without compromising the oncological margins. Methods. The study included a retrospective review of 82 cases of pelvic resections for pelvic tumors. Outcomes of acetabulum preservation (Group A) were compared with complete acetabular resection (Group B). Also, we compared outcomes of Type I+half resections (Group 1) with Type I+II resections (Group 2), and Type III+half resections (Group 3) with Type II+III resections (Group 4). Results. Group A (n=44) had significantly better functional outcome than Group B(n=38) with average MSTS93 score 22.3 vs 20.1 and average HHS 91.3 vs 82.5 (p<0.001). Group 1(n=14) and Group 2(n=12) had similar functional outcomes (mean MSTS93 score 22.07 vs 21.58 (p=0.597) and mean HHS 90.37 vs 86.51 (p=0.205)). Group 3(n=11) had significantly better functional outcome than Group 4(n=17), with mean MSTS93 score 22.8 vs 19.7 (p<0.001) and mean HHS 92.3 vs 80.1 (p<0.001). Oncological outcomes were similar among the groups. Conclusion. Trans-acetabular pelvic resections provide functional benefit over conventional resections without compromising oncological margins. There is a need to revisit and revise the pelvic resection planes

Aims. Custom triflange acetabular components (CTACs) play an important role in reconstructive orthopaedic surgery, particularly in revision total hip arthroplasty (rTHA) and pelvic tumour resection procedures. Accurate CTAC positioning is essential to successful surgical outcomes. While prior studies have explored CTAC positioning in rTHA, research focusing on tumour cases and implant flange positioning precision remains limited. Additionally, the impact of intraoperative navigation on positioning accuracy warrants further investigation. This study assesses CTAC positioning accuracy in tumour resection and rTHA cases, focusing on the differences between preoperative planning and postoperative implant positions. Methods. A multicentre observational cohort study in Australia between February 2017 and March 2021 included consecutive patients undergoing acetabular reconstruction with CTACs in rTHA (Paprosky 3A/3B defects) or tumour resection (including Enneking P2 peri-acetabular area). Of 103 eligible patients (104 hips), 34 patients (35 hips) were analyzed. Results. CTAC positioning was generally accurate, with minor deviations in cup inclination (mean 2.7°; SD 2.84°), anteversion (mean 3.6°; SD 5.04°), and rotation (mean 2.1°; SD 2.47°). Deviation of the hip centre of rotation (COR) showed a mean vector length of 5.9 mm (SD 7.24). Flange positions showed small deviations, with the ischial flange exhibiting the largest deviation (mean vector length of 7.0 mm; SD 8.65). Overall, 83% of the implants were accurately positioned, with 17% exceeding malpositioning thresholds. CTACs used in tumour resections exhibited higher positioning accuracy than rTHA cases, with significant differences in inclination (1.5° for tumour vs 3.4° for rTHA) and rotation (1.3° for tumour vs 2.4° for rTHA). The use of intraoperative navigation appeared to enhance positioning accuracy, but this did not reach statistical significance. Conclusion. This study demonstrates favourable CTAC positioning accuracy, with potential for improved accuracy through intraoperative navigation. Further research is needed to understand the implications of positioning accuracy on implant performance and long-term survival. Cite this article: Bone Jt Open 2024;5(4):260–268

Purpose of the study: The objective was to assess the diagnostic yield of angioscanner evaluation of arterial invasion of limb tumours before surgery. Material and methods: This was a prospective study conducted from January 2005 to May 2008 designed to assess 55 arterial segments and limb or pelvic tumours on the preoperative angioscan. Screen displays of the radiographic images were reread conjointly but radiologists using vascular analysis software. Contact of a large vessel with the tumour was classified as follows: fatty line, contact less than 90° of the vessel circumference, contact less than 180°, contact ≥ 180°. Intraoperative vessel-tumour contact was classified as follows: cleavable, non-dissectible. Agreement between the angioscan and the operative findings was analysed. Results: Forty-five arteries were cleavable and ten non-dissectible. All arteries that were separated from the tumour by a fatty plane or were in contact over less than 90° of the circumference of the vessel were cleavable at surgery (n=37/37). The sensitivity, specificity and diagnostic accuracy and the rate of positive scan for probable arterial contact > 180° were 90, 93, 93 and 13.5% respectively. Conclusion: The angioscanner provides a satisfactory means for predicting vascular invasion of limb and pelvic tumours and contributes pertinently to the pre-operative work-up

Introduction. The pelvis has always been a difficult area for surgeons, with high complication rates from surgery and the perception of poor oncological outcomes. The aim of the study was to look at the surgical and oncological outcomes of pelvic tumours treated at our centre. Methods. From the 3100 primary bone tumours seen at the ROH. Information was retrieved on 539 patients seen with a primary bone tumour of the pelvis. The demographic details, oncological and surgical outcomes were reviewed. Results. The mean age at presentation (39 yrs old) and duration of symptoms prior to diagnosis (30 weeks) were both significantly greater than the appendicular skeleton. The volume at resection was 3.8 times greater than the appendicular skeleton. The rates of wide surgical margins and response to chemotherapy were significantly poorer (p<0.05) than the appendicular skeleton resulting in rates of local recurrence (27% vs 12%, p<0.05) and overall survival that were poorer that the appendicular skeleton (51% vs 31% 10 yr survival, p<0.05). The dilemma of treating pelvic ewings will be discussed together with the subanalysis of the EICESS 92/EUROEWING 99 trials in relation to pelvic ewings sarcoma. Conclusions. Despite poorer oncological outcomes surgical resection of pelvic tumours can deliver good oncological and surgical results but has high complication rates compared to tumours of the appendicular skeleton

Introduction. The use of computer navigation has a potential to allow precise tumour resection and accurate reconstruction of the resultant defect. This can be useful in difficult areas such as pelvis, diaphyseal (intercalary) resections and geometric bony resections. Methods. We have carried out resections of musculoskeletal tumours in 7 patients using an existing commercial computer navigation system (Orthomap 3D). CT & MRI scans of each patient were fused preoperatively using navigation software and the tumour margins were marked. The planes of tumour resection were defined on the 3D image generated. During surgery, trackers were attached to bone with tumour and registration performed. Instruments attached to navigation tracker were then used to identify the predetermined resection points. Of the 4 pelvic tumours, 1 had biological reconstruction with extra corporeal irradiation, 3 had endoprosthetic replacement & 1 did not need any bony reconstruction. 1 patient with proximal femur tumour needing extraarticular resection had endoprosthetic replacement. The 2 tibial diaphyseal tumours had biological reconstruction. Results. Examination of the resected specimens revealed tumour free margins. Postoperative radiographs showed resection and reconstruction as planned in all cases. In the patient with extraarticular proximal femur resection the hip joint was inadvertently exposed whilst making the acetabular osteotomy & in one patient with pelvic tumour the intra-operative registration could not be accurately performed as she was overweight and a real time matching of anatomy & virtual images was not achieved. Discussion and Conclusion. The use of computer navigation in musculoskeletal oncology allows integration of local anatomy and tumour extent and thus resection margins can be identified accurately. Our experience so far has been encouraging. Further clinical trials (multicentre) are required to evaluate its long term impact including functional & oncological outcomes

The purpose of this study is to compare functional results of hemipelvectomy and internal hemipelvectomy following resection of pelvic tumours. The emotional acceptance of such surgery is also examined. From 1998 to 2003, 19 male and 13 female patients, aged from 6 to 76 years, underwent hemipelvectomy, and 12 male and seven female patients, aged from 13 to 65 years, underwent internal hemipelvectomy. In the series as a whole, follow-up ranged from 1 to 156 months. Five patients with external hemipelvectomy, six with internal hemipelvectomy and one who underwent internal hemipelvectomy followed by external hemipelvectomy were evaluated functionally, clinically and psychologically. Patients expressed emotional concern about body image and mobility. Psychosocial adjustment was difficult for all patients, but some were able to overcome their difficulties more easily than others. Patients with internal hemipelvectomy rather than external hemipelvectomy had more difficulty adjusting emotionally. The site of the tumour and morbidity rates, which remain high when limb-sparing surgery is performed for pelvic tumours, are important considerations when deciding upon the type of surgery. Patients and their families need extensive preoperative psychological preparation and postoperative psychotherapy is imperative

INTRODUCTION. Limb salvage surgery is a common treatment for patients who suffer from bone tumors. In the case of pelvic tumors this creates a challenge for the surgeon and the treatment remains controversial because the oncologic complications like local recurrence, dissemination and orthopaedic ones, like infection, haemorrhage, and mechanical problems of reconstructions Tumors affecting the acetabulum are a challenge for the surgeon because of the impact in the function of the extremity. There are many reconstruction techniques described in the literature like prosthesis, allograft systems, arthrodesis, etc…, but still there is not a gold standard due to the poor functional results at long term follow up, and the associated complications of all techniques. In this study we show the experience in our center on pelvic reconstructions after tumors affecting the acetabulum area (zone II). MATERIAL AND METHODS. We surgically treated 81 pelvic tumors from 1997 to 2009 following the Enneking and Dunham calssification attending to the localization of the tumor: Zone I 38 (iliac bone)Zone II 25 (acetabulum)Zone III 18 (pelvic branches)In zone II tumors we performed pelvic reconstruction in eight cases, with different type of prosthesis. In 5 cases we performed saddle prosthesis (group A) and in 3 cases we performed Coned-Stanmore Implants type prosthesis with sacro-iliac anchorage. The mean follow up of the serie was 3,5 years (1–6 years). In group A the mean follow up was 5 years and in group A and in group B the mean follow up was 1 year due to the recent implantation in our center of Coned type prosthesis for pelvic reconstruction. We evaluated our results with these two types of prosthesis. RESULTS. Oncologic: group A we had a local recurrence of 25% and 25% of the patients died. group B we had no cases of local or systemic recurrence and we didn't registered any death. Functional: In group A the patients showed local pain and difficulty to walk probably due to the change of the center of rotation of the hip and instability of the saddle prosthesis. In group B all patient's followed physical therapy programs without problems and were able to walk with crutches ten months after surgery. Complications:group A we had a 25% of perioperative infection and a 25% of dislocation of the prosthesis. In group B we did not have any of these complications. CONCLUSIONS. Saddle prosthesis mantain the length of the extremity and allow weight bearing but they do not give a good stability. Even if we only have one year follow up with this Coned prosthesis with sacro iliac anchorage we achieved much better functional results and a lower rate of complications

The purpose of this study was to evaluate the functional and oncological outcome of recycled autograft reconstruction after a wide excision for primary malignant bone tumor around the hip. From 1998 to 2015, 67 patients with a primary malignant bone tumor involving proximal femur or periacetabular zone (P2) were included. There were 36 males and 31 females with a mean age of 34 years (13 to 58). Of these, 29 patients had grade I or II chondrosarcoma, 28 high-grade osteosarcoma, 6 Ewing's sarcoma and 4 undifferentiated pleomorphic sarcoma. Enneking stage of all 67 patients was stage II. Of the resection classification, proximal femur resection was performed in 29 patients, P1+P2 in 15, P2+P3 in 14, P1+P2+P3 in 4, P2 only in 4, and P2+proximal femur in 1. Extracorporeally irradiated recycled autograft and liquid nitrogen frozen autograft were performed in 44 and 23 patients, respectively. At a mean follow-up of 98 months (10 to 239), 48 patients (72%) were continuously disease-free, 12 (18%) died of disease and 7 (10%) were alive with disease. The tumors of these patients who had died of disease were usually located in pelvic bones (10/12). Of these 37 patients with pelvic tumors, 7 patients (22%) had local recurrence, four of them received external hemipelvectomy. Other complications included hip dislocation in 2 patients, nerve injury in 2 and deep infection in 2. However, the above complications were rarely occurred in the patients with proximal femur reconstruction. The mean Musculoskeletal Tumor Society functional score were 77% (53 to 93). Recycled autograft reconstruction for primary malignant bone tumor around the hip is a valid method with acceptable morbidity and a favorable functional outcome

Introduction and Purposes. Custom made acetabular prosthesis are a valid option for the reconstruction after the resection of pelvic tumors. They should guarantee a stable and reliable reconstruction for the expected survival of the patient. Nevertheless in many cases periacetabular metastatic lesions have been compared to high grade (IIIA-B) Paprosky defects, but treated with low or intermediate longevity implants. Some complex post-traumatic scenarios or total hip arthroplasty (THA) multiple failures need a reconstruction according to oncologic criteria to fill in the huge defect and to obtain an acceptable function. The aim of the study is to compare 3D custom-made implants for tumors and for THA failures. Materials and Methods. Three custom-made implants after tumor resection (group A: 1 chondroblastic osteosarcoma, 1 bifasic synovialsarcoma, 1 high grade chondrosarcoma) were evaluated and compared to 3 acetabular complex reconstructions after non-oncologic bone defect (group B: 3 cases of aseptic loosening after at least 2 revisions). All the implants were case-based designed, 3D printed, and realized with porous or trabecular surfaces on a Titanium base prosthesis. Age range 16–70 ys in oncologic patients and 60–75 ys in non-oncologic patients. The bone defect to be reconstructed after tumor resection was classified according to Enneking zones (1 type 1-2-3 resection, 1 type 2 resection, 1 partial type 2 resection). Non-oncologic cases were comparable in term of remaining bone stock and classified according to Paprosky classification for acetabular defects as 1 type IIIA an 2 type IIIB. Complications, MSTS functional score, necessity of walking-aids were evaluated at minimum follow up of 1 year. Results. In both groups, good functional results were obtained (MSTS score 25/30 in both groups). No cases of aseptic loosening and no infection occured. After 3 months of partial or no weight-bearing on the operated limb, 3 patients were able to walk unaided and 3 walked with one cane or crutch. No limb length discrepancy (major than 2 cm) were observed. Limping was present in oncologic cases due to muscle resection. Overall better results in term of satisfaction and quality of life were obtained in younger (oncologic) patients. Conclusions. Complex THA revision cases can sometimes be considered for a reconstruction with oncologic criteria. Even if indications are limited an acceptable functional results can be obtained. In the past for these cases a Girldestone resection was the only option. A collaboration among orthopaedic oncologist and hip arthroplasty surgeons is advisable in major orthopaedic centers to improve the prosthetic design and the functional results

The surgical management of musculoskeletal tumours is a challenging problem, particularly in pelvic and diaphyseal tumour resection where accurate determination of bony transection points is extremely important to optimise oncologic, functional and reconstructive options. The use of computer assisted navigation in these cases could improve surgical precision. We resected musculoskeletal tumours in fifteen patients using commercially available computer navigation software (Orthomap 3D). Of the eight pelvic tumours, three underwent biological reconstruction with extra corporeal irradiation; three endoprosthetic replacement (EPR) and two required no bony reconstruction. Four diaphyseal tumours had biological reconstruction. Two patients with proximal femoral sarcoma underwent extra-articular resection and EPR. One soft tissue sarcoma of the adductor compartment involving the femur was resected with EPR. Histological examination of the resected specimens revealed tumour free margins in all cases. Post-operative radiographs and CT show resection and reconstruction as planned in all cases. Several learning points were identified related to juvenile bony anatomy and intra-operative registration. The use of computer navigation in musculoskeletal oncology allows integration of local anatomy and tumour extent to identify resection margins accurately. Furthermore, it can aid in reconstruction following tumour resection. Our experience thus far has been encouraging

Background. The surgical management of musculoskeletal tumours is a challenging problem, particularly in pelvic and diaphyseal tumour resection where accurate determination of bony transection points is extremely important to optimise oncologic, functional and reconstructive options. The use of computer assisted navigation in these cases could improve surgical precision. Materials and methods. We resected musculoskeletal tumours in fifteen patients using commercially available computer navigation software (Orthomap 3D). Results. Of the eight pelvic tumours, three underwent biological reconstruction with extra corporeal irradiation, three endoprosthetic replacement (EPR) and two required no bony reconstruction. Four diaphyseal tumours had biological reconstruction. Two patients with proximal femoral sarcoma underwent extra-articular resection and EPR. One soft tissue sarcoma of the adductor compartment involving the femur was resected with EPR. Histological examination of the resected specimens revealed tumour free margins in all cases. Post-operative radiographs and CT show resection and reconstruction as planned in all cases. Several learning points were identified related to juvenile bony anatomy and intra-operative registration. Discussion. The use of computer navigation in musculoskeletal oncology allows integration of local anatomy and tumour extent to identify resection margins accurately. Furthermore, it can aid in reconstruction following tumour resection. Our experience thus far has been encouraging

The surgical management of musculoskeletal tumours is a challenging problem, particularly in pelvic and diaphyseal tumour resection where accurate determination of bony transection points is extremely important to optimise oncologic, functional and reconstructive options. The use of computer assisted navigation in these cases could improve surgical precision and achieve pre-planned oncological margins with improved accuracy. We resected musculoskeletal tumours in ten patients using commercially available computer navigation software (Orthomap 3D, Stryker UK Ltd). Of the five pelvic tumours, two underwent biological reconstruction with extra corporeal irradiation, two endoprosthetic replacement (EPR) and one did not require bony reconstruction. Three tibial diaphyseal tumours had biological reconstruction. One patient with proximal femoral sarcoma underwent extra-articular resection and EPR. One soft tissue sarcoma of the adductor compartment involving the femur was resected with EPR. Histological examination of the resected specimens revealed tumour free margins in all cases. Post-operative radiographs and CT show resection and reconstruction as planned in all cases. Several learning points were identified related to juvenile bony anatomy and intra-operative registration. The use of computer navigation in musculoskeletal oncology allows integration of local anatomy and tumour extent to identify resection margins accurately. Furthermore, it can aid in reconstruction following tumour resection. Our experience thus far has been encouraging. Further clinical trials are required to evaluate its long-term impact on functional & oncological outcomes

Wound complications are common in patients with soft tissue sarcomas (STS) treated with surgical excision. Limited data is available on predictive factors for wound complications beyond the relationship to neo-adjuvant or adjuvant radiotherapy. Likewise, the association between blood transfusion, patient comorbidities and post-operative outcomes is not well described. In the present study we identified the predictive factors for blood transfusion and wound complications in patients undergoing surgical resection of soft tissue sarcoma from a national cohort. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients who underwent surgical resection of a STS from 2005 to 2013. Primary malignant soft tissue neoplasms were identified using the following ICD-9 codes: 171.2, 171.3 and 171.6. Patients treated with both wide excision and amputation were identified using the current procedural terminology (CPT) codes. Prolonged operative time was defined as greater than 90th percentile of time required per procedure. A multivariable logistic regression model was used to identify associations between patient factors and post-operative wound complications (superficial and deep surgical site infections (SSI), and wound dehiscence). A similar regression model sought to identify prognostic factors for blood transfusion and associations with post-operative outcomes. A total of 788 patients met our inclusion criteria. Of theses, 64.2% had tumours in the lower limb, 23.1% patients had tumours in the upper limb, and 12.7% patients had pelvic tumours. Six hundred and forty patients (81.2%) underwent surgical excision; 148 (18.8%) patients had an amputation. Multivariable logistic regression modeling identified American Society of Anaesthesiologist (ASA) class 3 and 4 (OR=2.3, P=0.03; OR=8.3, P=0.001, respectively), amputation (OR=14.0, P<0.001) and prolonged operative time (OR=4.6, P<0.001) as significant predictors of blood transfusion. Radiotherapy (OR=2.6, P=0.01) and amputation (OR=2.6, P=0.01) were identified as predictors of superficial SSI, whereas ASA class 4 (OR=6.2, P=0.03), prolonged operative time (OR=3.9, P=0.012) and return to the operating room (OR=10.5, P<0.001) were associated with deep SSI. Male gender (OR=1.8, P=0.03), diabetes (OR=2.3, P=0.03), ASA class 3 (OR=2.4, P=0.003), amputation (OR=3.8, P<0.001) and steroids (OR=4.5, P=0.03) were identified as predictors for wound dehiscence and open SSI. A national cohort demonstrates that male gender, diabetes, chronic steroid use, higher ASA score and radiotherapy are associated with an increased incidence of wound complications. One in twenty-three patients undergoing resection of an STS will require a blood transfusion, and this risk is correlated with amputation, prolonged operative time and increased ASA score. Strategies to decrease the risk of blood transfusion and wound complication should be considered for these patient groups

Background. Advances in diagnosis and treatment should mean that hindquarter amputation is now rarely needed. Unfortunately this is not the case. We have performed 166 of these amputations in the past 36 years. We have investigated the reasons why this procedure is still required and the outcomes following it. Method. A retrospective review of data stored on a prospective database. Results. Hindquarter amputation was used as treatment for 15% of all primary bone tumours affecting the pelvis. 146 were performed with curative intent but 20 were performed purely for palliation, usually to relieve pain. 96 of the procedures were needed as part of primary treatment, with the other 70 being needed following failure of local control after other surgical procedures. The indication for amputation in primary disease was almost always due to a significant delay in diagnosis, allowing tumours (particularly chondrosarcomas) to become massive by the time of diagnosis. The peri-operative mortality was 3% and 45% had major wound healing problems or infection. The median survival times after curative and palliative procedures were 36 months and 8 months respectively. The survival after hindquarter amputation for curative intent at 1, 3 and 5 years was 74%, 60% and 48%. Overall survival was better with chondrosarcoma – 52% of the patients surviving more than 10 years had chondrosarcoma. Phantom pain was a significant problem; fewer than 10% use their prosthesis regularly. Despite this functional scores averaged 61% – not significantly worse than patients who had undergone pelvic replacements!. Conclusion. Hindquarter amputation is still regularly required both for primary and salvage treatment in musculoskeletal oncology. Earlier diagnosis of pelvic tumours may avoid its use. Survival is not surprisingly worse than for tumours at other sites

A rare case of malignant transformation of fibrous dysplasia to chondrosarcoma involving the pelvis, treated by hemipelvectomy, was described by our team in a published case report. Twenty-four years later, the patient remains recurrence-free, with a good functional outcome that allows him to be independent in everyday activities and work in full time employment. Functional outcome following hemipelvectomy for pelvic malignancy is an evolving topic, as improved imaging and surgical techniques result in earlier diagnosis and a better overall prognosis. Sarcomas involving the pelvis still represent a challenging topic for surgeons. During the last twenty-four years, there have been some advances in the limb- salvage treatment of pelvic tumours. An internal hemipelvectomy is currently considered to be a reasonable treatment option, with good functional outcomes and achievement of satisfactory tumour clearance margins, in well- selected cases. In all cases however, the main focus should be in the adequate resection of the lesion, followed by restoration of maintenance of stability. We report a fascinating case of a patient who underwent internal hemipelvectomy without reconstruction for chondrosarcomatous transformation of pelvic fibrous dysplasia, with emphasis on the clear surgical resection margins and disease-free status of the patient and satisfactory functional outcome. We support that internal hemipelvectomy is an acceptable treatment option in well- selected cases and can achieve clear tumour resection margins, resulting in long term disease-free results, and a good limb- salvage functional outcome. We believe that joint stability in this patient is mainly a result of preservation of the adductor muscle group, which prevents the hip joint from upward migration and allows the patient to use his left leg for walking

Purpose of the study: Resection of sarcomas from the pelvis is particularly difficult because of the risk of injury to the vascular and neurological structures and the complex helicoidal anatomy of the iliac bone. Salvage of the lower limb is preferable but raises the risk of an insufficient resection margin. Imaging procedures (CT scan, magnetic resonance) allow preoperative planning but intraoperative landmarks are not always easy to recognise. Navigation might be highly useful for this type of surgery. Material and methods: Two patients with a sarcoma of the pelvis (chondrosarcoma and synovial sarcoma) underwent tumour resection using a navigation system. For the second patient, the cut for the bone graft was also navigated enabling reconstruction with a perfectly adjusted graft. The tumour was delimited on each magnetic resonance slice to produce a 3D reconstruction image. This volume was co-recorded on the scanner. The scan with the tumour limits was fed into the navigation machine. Resection planes were chosen taking into account the surgical approach, the type of reconstruction desired, and the healthy margin accepted. These planes were then transposed onto the allograft scan to enable an exactly adapted cut. Plaster prototypes were modelled from the scan of the patient’s pelvis and the allograft scan. The tumour resection and the allograft procedures were repeated on the prototypes using the navigation system. Results: The navigation system was used successfully as planned preoperatively. The planes of the cuts were as planned. The healthy margin was sufficient in all cases and confirmed at the pathology exam. Discussion: Navigation enables exact localisation in relation to the tumour throughout the operation. A healthy margin of one centimetre or more can be achieved safely. The allograft cut can be made by another surgeon simultaneously with the tumour resection, saving time. The allograft-host contact surface is improved giving a good congruency with the graft. Conclusion: Navigation is a very useful tool for resection of pelvic tumours and their reconstruction

Introduction and aims. After internal hemipelvectomy for malignant pelvic tumors, pelvic reconstruction is necessary for eventual weight bearing and ambulation. Non-vascularised, fibular grafts (NVFG) offer fast, and stable reconstruction, post- modified Enneking's type I and I/IV resection. This study aimed to evaluate the success of graft union and patient function after NVFG reconstruction. Methods. From 1996 to 2009, 10 NVFG pelvic reconstructions were performed after internal hemipelvectomy in four cases of chondrosarcoma, three of Ewing's sarcoma, and single cases of osteosarcoma, malignant peripheral nerve sheath tumour, and malignant fibrous histiocytoma. A key indication for internal hemipelvectomy was sciatic notch preservation confirmed by preoperative MRI. Operation time and complications were recorded. The mean follow-up was 31.1 months (range: 5 to 56), and lower limb function was assessed using the Musculoskeletal Tumour Society scoring system. Plain radiographs and/or computer tomography were used to determine the presence or absence of NVFG union. Results. The mean operation time was four hours and 56 mins, with no major intraoperative complications and partial wound break-down in only one patient. The NVFG united successfully in all patients, with a mean union time of 7.3 months. Post-operative deep infection did not occur in any case. Seven patients were eventually able to ambulate without a cane, and overall, the average function rating percentage was 75.4%. Recurrent tumour occurred in two cases following primary resection. Death from tumour-related disease occurred in one of the ten cases. Conclusions. NVFG is a stable and reliable pelvic reconstruction method after type I and type I/IV hemipelvectomy. Reliability may be linked to preservation of graft periosteum, and careful patient selection, limited to those with an intact sciatic notch. Furthermore, the relatively short operative time required should help minimise deep infection

Aim: The pelvis is a rare location for osteochondromas and differentiation from chondrosarcomas can be difficult. We aim to aid this differentiation using tends and demographics of treated cases. Methods and Results: Patients referred to a supra-regional bone tumour centre with pelvic tumours, consequently diagnosed as osteochondromas were studied to determine the clinico-pathological features that differentiate them from chondrosarcoma. Treatment outcome was also reviewed. 30 patients were studied with a mean follow-up of 32 months. The mean age at diagnosis was 34yrs (range 19–79). The male to female ratio was 1:1. The most common location was the ilium (19 patients), with the pubis and ischium accounting for a third of patients. Only 1 patient had an acetabular osteochondroma. Median duration of symptoms prior to referral was 6 months (1–79). Pain without a lump was the main presenting symptom (16 patients), followed by lump with pain (6), and lump alone (6). Two patients presented with obstructive labour requiring emergency procedures. The lesions were solitary in 24 and associated with hereditary multiple exostosis (HME) in 6 patients. 1 patient had a radiation induced lesion. The lesions showed increased uptake on bone scans and the cartilage cap was less than 10mm in all but 2 patients. Treatment was surgical excision in 21 patients and observation with serial radiographs in 9. Histological examination confirmed osteochondroma in all patients, however 1 patient with HME had areas of Grade I malignancy. Significant surgical complications occurred in 1 patient who developed pulmonary embolism. Conclusion: We conclude that symptoms from osteochondromas of the pelvis are similar to those with chondrosarcomas and increased uptake on bone scans is seen in both. However, a tumour with a cartilage cap larger than 10mm or arising from the acetabulum is unlikely to be an osteochondroma