Periacetabular Tumor Resection Research Articles

Novel positioning guiders accurately assist in situ acetabular reconstruction for patients undergoing pelvic bone tumor resection.

Acetabular reconstruction in situ after extensive pelvic resection is technically challenging. The aim of this study was to investigate the feasibility of positioning guiders for acetabular reconstruction following pelvic tumor resection and the clinical benefit brought by the approach. The study included patients who underwent acetabular reconstruction following periacetabular tumor resection using a modular hemipelvic prosthesis. In the guider-assisted group (n = 14), guiders were designed and applied to assist acetabular reconstruction. In the traditional operation group (n = 18), the patients underwent the same surgery but without the guiders. The displacement of the hip rotation center before and after surgery was calculated. The complications and the Musculoskeletal Tumor Society-93 scores were documented. The overall displacement of the hip rotation center was significantly reduced in the guider-assisted group compared with the traditional operation group (13.83 ± 4.06 vs. 22.95 ± 9.18mm in P = 0.000, 95%CI 3.90-12.96), especially in the anteroposterior axis (3.77 ± 3.03 versus 13.51 ± 9.43mm in P = 0.000, 95%CI 3.45-13.09). Guider-assisted acetabular reconstruction reduced the risk of prosthesis dislocation compared with the traditional operation (dislocation risks: 1/14, 7.1% vs. 4/18, 22.2%). Positioning guiders can effectively and conveniently help place the modular hemipelvic prosthesis at the native position, which might potentially reduce the risk of prosthesis dislocation. Therapeutic level III.

3D-Printed custom-made hemipelvic endoprosthetic reconstruction following periacetabular tumor resection: utilizing a novel classification system

BackgroundCustomized 3D-printed pelvic implants with a porous structure have revolutionized periacetabular pelvic defect reconstruction after tumor resection, offering improved osteointegration, long-term stability, and anatomical fit. However, the lack of an established classification system hampers implementation and progress.MethodsWe formulated a novel classification system based on pelvic defect morphology and 3D-printed hemipelvis endoprostheses. It integrates surgical approach, osteotomy guide plate and prosthesis design, postoperative rehabilitation plans, and perioperative processes.ResultsRetrospectively analyzing 60 patients (31 males, 29 females), we classified them into Type A (15 patients: Aa = 6, Ab = 9), Type B (27 patients: Ba = 15, Bb = 12), Type C (17 patients). All underwent customized osteotomy guide plate-assisted tumor resection and 3D-printed hemipelvic endoprosthesis reconstruction. Follow-up duration was median 36.5 ± 15.0 months (range, 6 to 74 months). The mean operating time was 430.0 ± 106.7 min, intraoperative blood loss 2018.3 ± 1305.6 ml, transfusion volume 2510.0 ± 1778.1 ml. Complications occurred in 13 patients (21.7%), including poor wound healing (10.0%), deep prosthesis infection (6.7%), hip dislocation (3.3%), screw fracture (1.7%), and interface loosening (1.7%). VAS score improved from 5.5 ± 1.4 to 1.7 ± 1.3, MSTS-93 score from 14.8 ± 2.5 to 23.0 ± 5.6. Implant osseointegration success rate was 98.5% (128/130), with one Type Ba patient experiencing distal prosthesis loosening.ConclusionThe West China classification may supplement the Enneking and Dunham classification, enhancing interdisciplinary communication and surgical outcomes. However, further validation and wider adoption are required to confirm clinical effectiveness.

Biomechanical and clinical outcomes of 3D-printed versus modular hemipelvic prostheses for limb-salvage reconstruction following periacetabular tumor resection: a mid-term retrospective cohort study

BackgroundDebates persist over optimal pelvic girdle reconstruction after acetabular tumor resection, with surgeons grappling between modular and 3D-printed hemipelvic endoprostheses. We hypothesize superior outcomes with 3D-printed versions, yet scarce comparative research exists. This study fills the gap, examining biomechanics and clinical results retrospectively.MethodsFrom February 2017 to June 2021, we retrospectively assessed 32 patients undergoing en bloc resection for malignant periacetabular tumors at a single institution. Primary outcome: limb function. Secondary outcomes: implant precision, hip joint rotation center restoration, prosthesis-bone osteointegration, and complications. Biomechanical characteristics were evaluated through finite element analysis on pelvic defect models.ResultsIn the 3D-printed group, stress distribution mirrored a normal pelvis, contrasting the modular group with elevated overall stress, unstable transitions, and higher stress peaks. The 3D-printed group exhibited superior functional scores (MSTS: 24.3 ± 1.8 vs. 21.8 ± 2.0, p < 0.05; HHS: 79.8 ± 5.2 vs. 75.3 ± 3.5, p < 0.05). Prosthetic-bone interface osteointegration, measured by T-SMART, favored 3D-printed prostheses, but surgery time (426.2 ± 67.0 vs. 301.7 ± 48.6 min, p < 0.05) and blood loss (2121.1 ± 686.8 vs. 1600.0 ± 505.0 ml, p < 0.05) were higher.ConclusionsThe 3D-printed hemipelvic endoprosthesis offers precise pelvic ring defect matching, superior stress transmission, and function compared to modular endoprostheses. However, complexity, fabrication expertise, and challenging surgical implantation result in prolonged operation times and increased blood loss. A nuanced consideration of functional outcomes, complexity, and patient conditions is crucial for informed treatment decisions.Level of evidenceLevel III, therapeutic study (Retrospective comparative study).

Clinical outcomes in patients with neurological disorders following periacetabular tumor removal and endoprosthetic reconstruction of the hemipelvis.

Surgical treatment of musculoskeletal tumors in the periacetabular region present extremely difficult due to the complex anatomy and need for reconstruction. Orthopedic surgeons face more difficulties in patients with neurological conditions, which can cause increased muscle tone, an elevated risk of fractures, and compromised bone quality. There is limited evidence regarding endoprosthetic reconstruction for periacetabular tumors in individuals with neurological disorders. We conducted a single-center retrospective study to examine the outcomes of patients with preexisting neurological conditions who underwent surgery to remove periacetabular tumors and who underwent endoprosthesis reconstruction. Clinical presentation, detailed neurological conditions, complications, and functional outcomes were studied. Sixteen out of the 838 patients were identified (1.91%), with a mean follow-up time of 33 months. The primary neurological conditions encompassed Parkinson's disease, Alzheimer's disease, dementia, and cerebral ischemic stroke. Every patient was diagnosed with periacetabular lesions that were either primary or oligometastatic. They underwent tumor resection and subsequently received endoprosthetic reconstruction of the hemipelvis. Three patients developed metastasis lesions later, and two patients experienced tumor recurrence. Five cases experienced hip dislocation-one with periprosthetic fracture and one with surgical site infection. The position of the prosthetic rotating center was not correlated with dislocation. The reoperation rate was 31.25%. The cohort of patients all presented with more extended hospital stays and rehabilitation. In 3 patients, the general functional score was good, while in 6 patients, it was fair; in 7 patients, it was regarded as poor. The average MSTS93 score was 49.71%. Endoprosthetic reconstruction after periacetabular tumor resection is an effective way to eliminate tumors and salvage limbs. However, this group of patients has an increased likelihood of secondary surgery, complications, extended hospital stay, and no significant improvement in functional outcomes. Despite the diverse nature of the cohort, it is recommended to consider enhanced soft tissue reconstruction, supervised functional recovery and rehabilitation training.

SURGICAL PROCEDURE FOR PELVIC PERIACETABULAR BONE TUMOR DEFECTS

Pelvic bone tumor and traumatic injuries are causes to a numeric of diagnostic, treatment and subsequent obtaining of positive functionalresults problems, which significantly affects the patientʼs quality of life. The most prognostically difficult are acetabulum areas defects. Its adequate restoration affects the further walking function. Goal. To develop a surgical reconstruction of the periacetabular tumor resection defects. Methods. A new surgical reconstruction procedure of the pelvic periacetabular defects were developed and submitted. It consists in using of artificial material polyethyleneterephthalate («Attachment tube») replacing, which is pre-filled with bone allograft and sutures transosseously fixed to the pubic bone or to the pubic/ischial bones. Another «Attachment tube» fragment is used to fix the femur head to the indicated allograft implant. The strength and bioactive characteristics of the «Attachment tube» in combination with bone allograft make it possible to obtain the equivalent of the acetabulum and restorethe full weight bearing and walking function with a certain range of motion in the restored acetabulum area. Results. The proposed method was clinically tested on 9 patients with evaluated follow up. Satisfactory functional results were obtained: (52.6 ± 20.0) % on the MSTS scale. Complications were analyzed. Conclusions. The use of novel surgical procedure for pelvic periacetabular bone tumor defects has a number of advantages over the existing ones.The biological materials using, restoration of anatomical relations in the «hip joint» makes it possible to restore the lower limb function with a good range of motion. The obtained results prove authorʼs method using can give acceptable results in the treatment of periacetabulum tumor leasions patients.

Less is better than more with resection of periacetabular tumors - A retrospective 16 years study and literature review.

Wide resections of periacetabular tumors create a sizeable bony defect that inevitably results in severe loss of function. Reconstruction of such defects usually requires using large metal implants, a feature associated with considerable surgery extension and complications. The aim of this study is to report resection with no reconstruction of the bony defect. In this retrospective study, we reviewed a consecutive series of 16 patients diagnosed with malignant periacetabular tumors and underwent en-bloc resection without reconstructing their remaining bone defect. Records were reviewed of 16 consecutive patients diagnosed with malignant periacetabular tumors and underwent en-bloc resection without reconstructing their remaining bony defect. Measurements included: the duration of surgery, blood loss, hemoglobin levels and the need for blood transfusions, data on other hospitalization characteristics, and intraoperative and postoperative complications. Sixteen patients with malignant periacetabular bone tumors and extensive bone destruction underwent wide periacetabular tumor resection with a mean follow-up of 75 months and a mean age of 53 years. The average HOOS score was 46 (range: 20 to 76), and the mean MSTS score was 13% (range: 0 to 15). The mean operative time was 4.1 h, and the mean blood loss was 1200 ml. At their most recent follow-up, patients had a mean shortening of their operated extremity of 4.8 cm, and all could ambulate with assisting devices. Wide resection of periacetabular tumors without reconstruction provides acceptable levels of function and was associated with shorter surgical time, less blood loss and fewer postoperative complications compared to resection with reconstruction. Therefore, this approach may be considered a viable surgical option in patients with an extensive malignant periacetabular. Retrospective study.

What's New in Musculoskeletal Tumor Surgery.

What's New in Musculoskeletal Tumor Surgery.

Comparison of customized 3D-printed prosthesis and screw-rod-cage system reconstruction following resection of periacetabular tumors.

Background and purposeVarious operative methods are used for reconstructing pelvic girdle after resection of primary malignant periacetabular tumor has been reported. The objective of this study was to evaluate the accuracy, effectiveness, and safety of customized three dimensional-printed prosthesis (3DP) in the reconstruction of bone defects compared with conventional reconstruction using the screw-rod-cage system.MethodsA retrospective case–control analysis of 40 patients who underwent pelvic tumor resection and reconstruction with a customized 3D-printed prosthesis (3DP), or screw-rod-cage system (SRCS) between January 2010 and December 2019 was performed. The minimum follow-up time for patients alive was 2 years. Blood loss, operation time, complications, surgical margin, local recurrence, distant metastases, status at time of latest follow-up, MSTS-93 score, Harris hip score, and postoperative radiographic parameters were recorded. Moreover, overall survival, tumor-free survival, and prosthesis survival rates in both groups were compared.ResultsCustomized 3DP reconstruction was performed in 15 patients, and SRCS reconstruction was done in 25 patients. The group of patients treated with customized 3DP reconstruction had significantly shorter operation time (323.7 ± 83.7 vs. 393.6 ± 98.8 min; P = 0.028) and more precise (all P < 0.05) radiographic reconstruction parameters than patients in the SRCS group. Fewer complications (P = 0.026), better MSTS score (P = 0.030), and better Harris hip score (P = 0.016) were achieved in the 3DP group. Furthermore, the survival rate of prosthesis was also significantly better in the 3DP group (P = 0.039). However, blood loss, surgical margin, local recurrence, distant metastases, and status at time of latest follow-up had no significant difference between two groups.ConclusionCompared with the screw-rod-cage system reconstruction, the customized 3D-printed prosthesis reconstruction is equally safe and effective, but it is more accurate and time-saving and is associated with fewer complications.

Computer-Aided Design and 3D Printing of Hemipelvic Endoprosthesis for Personalized Limb-Salvage Reconstruction after Periacetabular Tumor Resection.

3D-printed hemipelvic endoprosthesis is an emerging solution for personalized limb-salvage reconstruction after periacetabular tumor resection. Further clinical studies are still required to report its surgical characteristics, outcomes, benefits and drawbacks. Sixteen consecutive patients underwent periacetabular tumor wide resection and pelvic reconstruction with a 3D-printed hemipelvic endoprosthesis from 2018 to 2021. The surgical characteristics and outcomes are described. The mean follow-up duration was 17.75 months (range, 6 to 46 months). Five patients underwent surgery for type I + II resection and reconstruction, seven for type II + III resection and reconstruction, three for type II resection and reconstruction, and one for type I + II + IV resection and reconstruction. The incidence of postoperative complication was 12.5% (2/16) for deep venous thrombosis (DVT), 12.5% (2/16) for pneumonia, and 12.5% (2/16) for would deep or superficial infection. During follow-up, two patients (12.5%) suffered hip dislocation and underwent revision surgery. CT demonstrated an obvious prosthetic porous structure–bone fusion after follow-up of at least 6 months. At the final follow-up, 12 lived with no evidence of disease while four lived with disease; no patients experienced pain; and 15 had independent ambulation, with a mean Musculoskeletal Tumor Society (MSTS) score of 85.8% (range, 26.7% to 100%). 3D-printed hemipelvic endoprosthesis facilitates wide resection of periacetabular tumor and limb-salvage reconstruction, thus resulting in good oncological and functional outcomes. The custom-made nature is able to well mimic the skeletal anatomy and microstructure and promote osseointegration. Perioperative complications and rehabilitation exercise still need to be stressed for this engineering technology-assisted major orthopedic surgery.

A novel limb-salvage reconstruction strategy with a custom hemipelvic endoprosthesis and preserved femoral head following the resection of periacetabular tumors: A preliminary study.

The treatment of periacetabular malignancy frequently challenges surgeons. To simplify the surgical procedure, we performed a novel reconstruction strategy preserving the femoral head for patients with periacetabular malignancies. We retrospectively reviewed 14 patients who underwent total en bloc resection of a periacetabular tumor and reconstruction of the hip joint with an individualized hemipelvic endoprosthesis and remaining femoral head from July 2015 to January 2019 at our center. Regions of pelvic resection: region II-4 (28.6%), region I + II-5 (35.7%), region II + III-2 (14.3%) and region I + II + III-3 (21.4%). The oncological outcomes were that 13 patients survived without disease and one patient survived with lung metastasis. None of the patients experienced local recurrence (range: 20-62 months; mean: 32 months). The incidence of postoperative complications was 35.7%, including delayed wound healing and deep venous thrombosis. No prosthesis-related complications occurred until the last follow-up in this study (range: 20-62 months; mean: 32 months). The mean Musculoskeletal Tumor Society functional outcome score was 23.2. The mean Toronto Extremity Salvage Score of the patients was 75.7 points, with a mean limb discrepancy of 1.51 cm (range: 0.5-3.2 cm). Reconstruction with preservation of the femoral head showed acceptable early functional and oncological outcomes, and it had an acceptable complication rate.

Clinical application of 3D-printed patient-specific guide plate combined with computer navigation in acetabular reconstruction following resection of periacetabular tumors.

BackgroundThe 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.MethodsThe 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.ResultsThe 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.ConclusionsPSG + CN has potential advantages in improving the accuracy and safety of acetabular positioning and reconstruction.

CORR Insights®: Does Adding Femoral Lengthening at the Time of Rotation Hip Transposition After Periacetabular Tumor Resection Allow for Restoration of Limb Length and Function? Interim Results of a Modified Hip Transposition Procedure.

CORR Insights®: Does Adding Femoral Lengthening at the Time of Rotation Hip Transposition After Periacetabular Tumor Resection Allow for Restoration of Limb Length and Function? Interim Results of a Modified Hip Transposition Procedure.

Preliminary proposal: a classification system for reconstruction with autologous femoral head after periacetabular tumors resection

BackgroundAlthough researchers have adopted various methods for the resection and reconstruction of periacetabular tumors, the total incidence rate of complications remains high. Aiming for preserving the acetabulum and reducing the risk of complications, we applied a surgery method using tumor-free autologous femoral head to reconstruct the defective acetabulum after resection of periacetabular tumors followed by performing a conventional total hip arthroplasty (THA). Moreover, we proposed a preliminary classification system for these surgery methods.MethodsWe retrospectively reviewed 6 patients treated with acetabulum reconstruction combined with autologous femoral head following peri-acetabulum resection between April 2010 and May 2018. All patients were diagnosed as periacetabular tumors including chondrosarcoma (n = 5) and chondroblastoma (n = 1). Clinical data such as age, diagnosis, complications, local recurrence or metastasis, and function (Musculoskeletal Tumor Society 1993, MSTS93) were documented. The average time of follow-up was 62.5 months (range, 17 to 106 months).ResultsA total of 5 patients survive with average MSTS93 score of 27.8 points (range, 26–30). One patient, suffering from multiple bone metastasis prior treatment, ended up dying. One who had received radiotherapy before surgery had poor incision healing. Further, a classification system was preliminary proposed in 2 patients involving the pubis (type A) and 4 patients involving ischium (type B).ConclusionsBased on the results, we preliminary proposed a classification system for reconstruction with autologous femoral head after periacetabular low malignant tumors resection. The clinical results suggested that surgery methods involving pubis (type A) and ischium (Type B) are safe and feasible. However, further researches should be conducted to verify our classification system.

Reconstruction after periacetabular tumor resection with Lumic® endoprosthesis: What are the midterm results?

This study aimed to analyze the midterm outcomes of LUMiC® endoprosthetic reconstruction following periacetabular resection of primary bone sarcomas and carcinoma metastases. We retrospectively reviewed the charts of 21 patients (11 male [52.3%], 10 female [47.6%]; mean age 47 ± 16 years) for whom a LUMiC® endoprosthesis (Implantcast) was used to reconstruct a periacetabular defect after internal hemipelvectomy. The tumor was pathologically diagnosed as Ewing's sarcoma in six (28.5%), chondrosarcoma in 10 (47.6%), and bone metastasis from carcinoma in five (23.8%) patients. The median follow-up of patients was 57.8 months (95% confidence interval: 51.9-63.7). The implant survival rate at 1, 2, and 5 years were 95.2%, 85.7%, and 80.9%, respectively. The overall complication rate was 33.3% (n = 7). Four (19%) complications resulted in reconstruction failure. Total reoperation rate was 28.5% (n = 6). The complications were soft tissue failure/dislocation in two patients, aseptic loosening in one, infection in two, and local recurrence in two. At the time of study, seven patients were alive with no evidence of disease, seven were alive with disease, and seven died of disease. The 5-year overall survival rate and local recurrence-free survival rates were 67% and 76%, respectively. The median Musculoskeletal Tumor Society score at final follow-up was 70% (range: 50%-86.6%). We conclude that LUMiC® endoprosthesis provides good functional outcomes and a durable reconstruct. Even though this reconstruction method presents some complications, it provides a stable pelvis in the management of periacetabular malignant tumors.

Outcomes following periacetabular tumor resection: A 25-year institutional experience.

Following tumor resection involving the acetabulum (periacetabular), various methods of reconstruction exist. The objective of this study was to analyze functional outcomes and complication rates by extent of periacetabular tumor resection, as well as by method of reconstruction. Twenty-three patients underwent periacetabular resection for a primary pelvic bone tumor from 1993-2018 at a single institution. Complications were documented and functional outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) scoring system. Mean age was 42.8 ± 22.6 years. Mean follow-up was 107 ± 75 months. MSTS scores were highest in patients with allograft reconstruction (80.2%) and lowest in saddle reconstruction (38.0%). MSTS scores were higher in patients with Type II periacetabular resection alone compared with Type II + additional resection (78.6% vs 60.3%; P = .019). Complications were lower in patients with Type II periacetabular resection alone (75% vs 28.6%; P = .036). Complications were highest following allograft reconstruction (78%) and lowest following hemipelvectomy without reconstruction (20%). Patients who underwent allograft/APC or nonsaddle metallic reconstruction experienced the highest functional outcome scores, but also sustained a higher complication rate than patients with hemipelvectomy without reconstruction. Patients with resection of ilium and/or pubis in addition to the periacetabular region had lower functional outcome scores and higher risk for complication.

Results of modular endoprosthetic reconstruction of periacetabular bone defects in patients with tumors of the acetabulum and hip joint

Introduction. surgical treatment of patients with pelvic bone tumors, in particular periacetabular tumors, remains challenging. There are many different reconstruction options after resection of these tumors. These include allo- and autografts, megaprosthesis, saddle endoprosthesis, custom-made endoprosthesis, 3D printing endoprosthesis, and femur transposition with the formation of neo-arthrosis. However, all of them are characterized by technical complexity and high risk of postoperative complications. There is still no standard procedure for reconstruction after resection of malignant periacetabular tumors. To date, modular endoprosthesis is a well-established reconstructive device in orthopaedic oncology to manage wide bone resections. Modular systems provide patient-specific endoprostheses that could be modified during surgery. In this article, we present the results of modular acetabular endoprostheses in the treatment of patients with periacetabular tumors. Material and Methods. From 2011 to 2018, 30 patients underwent modular endoprosthetic reconstruction after periacetabular resection. There were 13 (43 %) male and 17 (57 %) female patients aged from 23 to 63 years (median age 45 years). Primary malignant bone tumors were detected in 19 (63 %) patients, giant cell tumor in 5 (17 %), local soft tissue sarcoma in 1 (3 %), solitary metastases of kidney cancer in 2 (7 %) and recurrent sarcoma after previous surgical treatment in 3 (10 %) patients. Results. The average duration of surgery was 310 minutes (range: 145-520 minutes), blood loss was 5520 ml (range: 600-20000 ml). The median follow-up time was 36 months. Histological examination revealed a positive resection margin in 3 (10 %) patients. At a follow-up from 6 to 40 months, disease progression was detected in 10 (33 %) patients. Eight (27 %) patients died on disease progression. Complications of various types were diagnosed in 11 (37 %) patients. Infectious complications were the most common (30 % of patients). The average value of the functional assessment by the MSTS scale was 59 % (15-82%). Conclusion. Modular endoprosthetic replacement for tumors of the acetabulum and hip joint is a promising surgical technique allowing adequate functional results to be achieved.

Reconstruction with a novel combined hemipelvic endoprosthesis after resection of periacetabular tumors involving the sacroiliac joint: a report of 25 consecutive cases

BackgroundOur purpose was to examine the outcomes of patients who underwent extensive resection of periacetabular tumors involving the sacroiliac joint and joint reconstruction with a hemipelvic endoprosthesis.MethodsThe records of 25 consecutive patients diagnosed with Enneking type I/II/IV pelvic tumors from 2010 to 2016 who received resection and hemipelvic endoprosthesis reconstruction were retrospectively reviewed.ResultsThe median follow-up period was 48 months. At the most recent follow-up, 11 patients were alive, with estimated 3- and 5-year survival rates of 45.6 and 38.0%, respectively. Fourteen patients died, with a mean survival of 20.8 months, and 8 patients had local recurrence at an average of 9.3 months after surgery. Distal metastases were detected in 11 patients at an average of 11.0 months after surgery. The total complication rate was 56.0%, and the most common complications were wound healing disturbances (28.0%) and deep infections (16.0%). The prosthesis-related complication rate was 24.0%; periprosthetic infections and aseptic loosening were most common. The estimated 1- and 3-year prosthesis survival rates were 81.2 and 63.2%, respectively. The mean Musculoskeletal Tumor Society score was 48.0%. Function and prosthesis-related complications did not differ significantly after adding an extra screw fixation to the first sacral vertebra.ConclusionsReconstruction with the hemipelvic endoprosthesis described herein provides satisfactory function with a relatively low complication rate. Adding an extra screw fixation to the first sacral vertebra was not associated with any improvement in the clinical results after short-term follow-up. Improvement and further studies of this endoprosthesis are needed.

Multiflora and Gram-Negative Microorganisms Predominate in Infections Affecting Pelvic Endoprostheses Following Tumor Resection.

Periprosthetic infections after pelvic reconstruction are common, with reported rates ranging from 11% to 53%. Management of these infections is troublesome, as they commonly necessitate multiple surgical interventions and implant removal. The epidemiology and outcomes of these infections are largely unknown. The aim of this study was to analyze the causative microorganisms and the clinical outcome of treatment in a series of patients with pelvic endoprostheses affected by infection following tumor resection. In this retrospective, multicenter cohort study, we identified all patients who developed an infection after endoprosthetic reconstruction in periacetabular tumor resection, between 2003 and 2017. The microorganisms that were isolated during the first debridement were recorded, as were the number of reoperations for ongoing infection, the antimicrobial treatment strategy, and the outcome of treatment. In a series of 70 patients who underwent pelvic endoprosthetic reconstruction, 18 (26%) developed an infection. The type of pelvic resection according to the Enneking-Dunham classification was type P2-3 in 14 (78%) of these patients and type P2 in 4 (22%). Median follow-up was 66 months. Fourteen (78%) of the 18 patients with infection had a polymicrobial infection. Enterobacteriaceae were identified on culture for 12 (67%). Of a total 42 times that a microorganism was isolated, the identified pathogen was gram-negative in 26 instances (62%). Microorganisms associated with intestinal flora were identified 32 times (76%). At the time of latest follow-up, 9 (50%) of the patients had the original implant in situ. Of these, 2 had a fistula and another 2 were receiving suppressive antibiotic therapy. In the remaining 9 (50%) of the patients, the original implant had been removed. At the time of final follow-up, 3 of these had a second implant in situ. The remaining 6 patients had undergone no secondary reconstruction. Infections that affect pelvic endoprostheses are predominantly polymicrobial and caused by gram-negative microorganisms, and may be associated with intestinal flora. This differs fundamentally from mono-bacterial gram-positive causes of conventional periprosthetic joint infections and may indicate a different pathogenesis. Our results suggest that prophylaxis and empiric treatment may need to be re-evaluated. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Reconstruction using a constrained-type hip tumor prosthesis after resection of malignant periacetabular tumors: A study by the Japanese Musculoskeletal Oncology Group (JMOG).

We conducted a nationwide survey of prosthetic reconstruction using a constrained-type hip tumor prosthesis (C-THA) following resection of periacetabular tumors. Eighty patients with periacetabular tumors underwent wide resection and prosthetic reconstruction using C-THA at JMOG-affiliated institutions (39 males and 41 females; mean age, 46.7 years; mean follow-up period, 65 months). Primary bone or soft tissue sarcoma accounted for 75% of the cases. Adjuvant radiotherapy and chemotherapy were performed for 12 and 37 patients, respectively. There were 21 local recurrences (26%), necessitating amputation in 2 patients. Other postoperative complications included deep infection in 31 patients (39%), delayed wound healing in 25 (31%), and prosthesis-related complications requiring surgery in 7 (9%). Removal of the prosthesis was required in 23 patients (29%) (deep infection (n = 20), local recurrence resulting in amputation (n = 2), and outer cup displacement (n = 1). Patients whose abductor muscle was conserved or who underwent functional abductor muscle reconstruction showed significantly longer prosthesis survival. No postoperative wound complications occurred in three recent patients undergoing wound management with a RAM flap. The mean MSTS score was 43%. We analyzed the outcome of 80 patients with periacetabular tumors undergoing C-THA reconstruction. The rates of postoperative complication were still high, but comparable to those in previous studies. Our results suggest wound management using a RAM flap is useful for reducing wound complications.

Acetabular Reconstruction With Femoral Head Autograft After Intraarticular Resection of Periacetabular Tumors is Durable at Short-term Followup.

Pelvic reconstruction after periacetabular tumor resection is technically difficult and characterized by a high complication rate. Although endoprosthetic replacement can result in immediate postoperative functional recovery, biologic reconstructions with autograft may provide an enhanced prognosis in patients with long-term survival; however, little has been published regarding this approach. We therefore wished to evaluate whether whole-bulk femoral head autograft that is not contaminated by tumor can be used to reconstruct segmental bone defects after intraarticular resection of periacetabular tumors. In a pilot study, we evaluated (1) local tumor control, (2) complications, and (3) postoperative function as measured by the Musculoskeletal Tumor Society score. Between 2009 and 2015, we treated 13 patients with periacetabular malignant or aggressive benign tumors with en bloc resection, bulk femoral head autograft, and cemented THA (with or without a titanium acetabular reconstruction cup), and all were included for analysis here. During that time, the general indications for this approach were (1) patients anticipated to have a good oncologic prognosis and adequate surgical margins to allow this approach, (2) patients whose pelvic bone defects did not exceed two types (Types I + II or Types II + III as defined by Enneking and Dunham), and (3) patients whose medical insurance would not cover what otherwise might have been a pelvic tumor prosthesis. During this period, another 91 patients were treated with pelvic prosthetic replacement, which was our preferred approach. Median followup in this study was 36 months (range, 24-99 months among surviving patients; one patient died 8 months after surgery); no patients were lost to followup. Bone defects were Types II + III in five patients, and Types I + II in eight. After intraarticular resection, ipsilateral femoral head autograft combined with THA was used to reconstruct the segmental bone defect of the acetabulum. In patients with Types I + II resections, the connection between the sacrum and the acetabulum was reestablished with a fibular autograft or a titanium cage filled with dried bone-allograft particles which was enhanced by using a pedicle screw and rod system. Functional evaluation was done in 11 patients who remained alive and maintained the femoral head autograft at final followup; one other patient received secondary resection involving removal of the femoral head autograft and internal fixation, and was excluded from functional evaluation. Endpoints were assessed by chart review. Two patients experienced local tumor recurrence. Finally, eight patients did not show signs of the disease, one patient died of disease for local and distant tumor relapse, and four patients survived, but still had the disease. Three of these four patients had distant metastases without local recurrence and one had local control after secondary resection but still experienced system relapse. We observed the following complications: hematoma (one patient; treated surgically with hematoma clearance), delayed wound healing (one patient; treated by débridement), deep vein thrombosis (one patient), and hip dislocation (one patient; treated with open reduction). The median 1993 Musculoskeletal Tumor Society score was 83% (25 of 30 points; range, 19-29 points), and all patients were community ambulators; one used a cane, three used a walker, and nine did not use any assistive devices. In this small series at short-term followup, we found that reconstruction of segmental bone defects after intraarticular resection of periacetabular tumors with femoral head autograft does not appear to impede local tumor control; complications were in the range of what might be expected in a series of large pelvic reconstructions, and postoperative function was generally good. Level IV, therapeutic study.