Preservation of the contralateral sacral nerves during hemisacrectomy for sacral malignancies

Is 3D-printed self-stabilizing endoprosthesis reconstruction without supplemental fixation following total sacrectomy a viable approach for sacral tumours?

PURPOSE

The spinopelvic reconstruction poses significant challenges following total sacrectomy in patients with malignant or aggressive benign bone tumours encompassing the entire sacrum. In this study, we aim to assess the functional outcomes and complications of an integrated 3D-printed sacral endoprostheses featuring a self-stabilizing design, eliminating the requirement for supplemental fixation.

METHODS

We retrospectively analyzed patients with sacral tumours who underwent total sacrectomy followed by reconstruction with 3D-printed self-stabilizing endoprosthesis. Clinically, we evaluated functional outcomes using the 1993 version of the musculoskeletal tumour society (MSTS-93) score. Perioperative and postoperative complications were also documented.

RESULTS

10 patients met final inclusion criteria. The median age was 49 years (range, 31-64 years). The median follow-up time was 26.5 months (range, 15-47 months). Median postoperative functional MSTS-93 was 22.5 (range, 13-25). The median operation time was 399.5 min (305-576 min), and the median intraoperative blood loss was and 3200 ml (2400-7800 ml). Complications include wound dehiscence in one patient, bowel, bladder, and sexual dysfunction in four patients, cerebrospinal fluid leak in one patient, and tumour recurrence in one patient. There were no mechanical complications related to the endoprosthesis at the last follow-up.

CONCLUSION

The utilization of 3D-printed self-stabilizing endoprosthesis proved to be a viable approach, yielding satisfactory short-term outcomes in patients undergoing total sacral reconstruction without supplemental fixation.

Current Concepts in the Treatment of Giant Cell Tumor of Bone: An Update

Curettage is recommended for the treatment of Campanacci stages 1-2 giant cell tumor of bone (GCTB) in the extremities, pelvis, sacrum, and spine, without preoperative denosumab treatment. In the distal femur, bone chips and plate fixation are utilized to reduce damage to the subchondral bone and prevent pathological fracture, respectively. For local recurrence, re-curettage may be utilized when feasible. En bloc resection is an option for very aggressive Campanacci stage 3 GCTB in the extremities, pelvis, sacrum, and spine, combined with 1-3 doses of preoperative denosumab treatment. Denosumab monotherapy once every 3 months is currently the standard strategy for inoperable patients and those with metastatic GCTB. However, in case of tumor growth, a possible malignant transformation should be considered. Zoledronic acid appears to be as effective as denosumab; nevertheless, it is a more cost-effective option. Therefore, zoledronic acid may be an alternative treatment option, particularly in developing countries. Surgery is the mainstay treatment for malignant GCTB.

Enhanced recovery after surgery (ERAS) in sacral tumour surgery and comprehensive description of a multidisciplinary program: a prospective study in a specialized hospital in China

PURPOSE

There were fewer data to guide the application of enhanced recovery after surgery (ERAS) theory into sacral tumour surgery. In the present study, we were aiming to describe a multidisciplinary program of ERAS and evaluate the availability in sacral tumour surgery.

METHODS

This was a prospective study of patients with sacral tumour between March 2021 and September 2021 at a single centre. We proposed a multidisciplinary program of ERAS for pre-admission, preoperative, intraoperative, postoperative, and post-discharge clinical care which positively influenced outcomes of patients with sacral tumour. All patients were prospectively assigned into two groups, ERAS group in which patients received ERAS protocols (n = 63), No-ERAS group in which patients had conventional clinical pathways (n = 62). Patient data were collected which included demographics, preoperative preparation, detailed information of surgical procedure, 60-day reoperation rate, 60-day readmission, postoperative length of stay (PLOS), time to first ambulation and flatus after surgery, time to removal of last drainage tube, and visual analogue scale (VAS) score at first ambulation and discharge. Complications referred to ones that occurred within 60 days after surgery. The above parameters were compared between ERAS group and No-ERAS group.

RESULTS

Time to first ambulation after surgery in ERAS group (mean 20.9 h) was significantly shorter than that in No-ERAS group (mean 104.3 ho). Meanwhile, time to first flatus after surgery in ERAS group (mean 26.7 h) was also significantly shorter than that in No-ERAS group (mean 37.3 h). Patients in ERAS group had statistically shorter PLOS (10.7 days) as compared to that in No-ERAS group (13.8 days). In ERAS group, 19 of 63 patients (30.2%) were discharged within seven days after surgery as compared to seven of 62 patients (11.3%) in No-ERAS group. VAS score at first ambulation in ERAS group was not obviously higher than that in No-ERAS group though the time of first ambulation in ERAS group was statistically earlier than one in No-ERAS group. Furthermore, VAS score at discharge in ERAS group was significantly lower than that in No-ERAS group. The rate of postoperative incision necrosis was 6.3% (4/63) in ERAS group and 8.1% (5/62) in No-ERAS group and all of these nine patients underwent reoperation before discharge. The difference was not statistically significant in the wound complication of incision necrosis and 60-day reoperation rate. Only one readmission occurred in No-ERAS group due to the surgical site infection and also there was no significant difference of 60-day readmission rate between these two groups. Furthermore, there was no statistical difference of complications of femoral artery thrombosis and rectal rupture between ERAS group and No-ERAS group.

CONCLUSIONS

Our proposed ERAS pathway for sacral tumour surgery and early walking facilitate safe and prompt discharge. ERAS protocols of sacral tumour surgery could decrease PLOS without significantly increasing postoperative complications, 60-day readmission rate and 60-day reoperation rate. The application of ERAS pathway in the field of sacral tumour surgery should have personalized feature with regard to resection type.

Sacrectomy with Posterior-Only Approach in Sacral Tumors: An Analysis of 26 Cases and Review of Literature

BACKGROUND

Sacral masses can be removed using anterior, posterior, or combined approaches. Achieving total sacrectomy through a posterior-only approach results in a shorter procedure time, minimal tissue damage, and a reduced risk of complications. In this study, we aimed to share our experience with performing total sacrectomy using a posterior-only approach in 26 patients and to assess their clinical outcomes at our center.

MATERIALS AND METHODS

This retrospective study examines the clinical progression, surgical response, and outcomes of 26 patients with various sacral mass pathologies. We accessed patient information from our hospital records.

RESULTS

The study included 14 men (54%) and 12 women (46%), with an average age of 49.8 years. Most cases had a normal body mass index, while 6 were overweight. Sacrectomy was performed at a high level in 12 patients and at a middle level in 14 patients. In addition to pain, motor deficits were observed in 9 patients, and sphincter dysfunction was found in 5. Preoperative embolization was conducted for 11 patients. The most prevalent lesions were chordoma (8 patients), malignant peripheral nerve sheath tumor (4 patients), giant cell tumor (3 patients), and solitary plasmacytoma (3 patients). Only 1 patient experienced a temporary partial motor deficit after surgery. There were no instances of cerebrospinal fluid leakage. Five patients experienced local recurrence, and 1 had distant metastasis.

CONCLUSIONS

Performing sacrectomy for large or giant sacral tumors through a posterior approach is both feasible and safe, resulting in reduced morbidity and no significant change in overall survival.

Pelvic exenteration: a review of current issues/controversies

Management of advanced or recurrent pelvic cancer has evolved dramatically over the past few decades. Patients who were previously considered inoperable are now candidates for potentially curative surgery and avoid suffering with intractable symptoms. Up to 10% of primary rectal cancers present with isolated advanced local disease and between 10% and 15% of patients develop localized recurrence following proctectomy. Advances in surgical technique, reconstruction and multidisciplinary involvement have led to a reduction in mortality and morbidity and culminated in higher R0 resection rates with superior longer-term survival outcomes. Recent studies boast over 50% 5-year survival for rectal with an R0 resection. Exenteration has cemented itself as an important treatment option for advanced primary/recurrent pelvic tumours, however, there are still a few controversies. This review will discuss some of these issues, including: limitations of resection and the approach to high/wide tumours; the role of acute exenteration; re-exenteration; exenteration in the setting of metastatic disease and palliation; the role of radiotherapy (including intra-operative and re-irradiation); management of the empty pelvis; and the impact on quality of life and function.

Sacrectomy with Ilio-Lumbar Stabilization Due to Low-Grade Chondrosarcoma of Sacrum and Iliac Wing. Case Report of the First Surgery Performed in the Republic of North Macedonia

Low - grade chondrosarcomas are primary malignant bone tumors that are resistant to chemo- and radiotherapy and are treated surgically. Sacral localization makes surgical resection technically difficult due to position, anatomic structures involved, and large tumor size at detection. The risk of complications is high. We present the introduction of a novel surgical technique in our country, sacrectomy with ilio-lumbar stabilization. This was performed on a 67-year-old man with low-grade chondrosarcoma of the sacrum with sacroiliac joint involvement. The procedure was performed via an antero-posterior approach in two stages. Ilio-lumbar fixation with a mesh cage bridge was used to obtain spinopelvic continuity and stability. Sacrectomy is a technically demanding procedure that requires careful preoperative planning and a multidisciplinary approach, as well as high level of surgical experience.

Iliosacral Bone Tumor Resection Using Cannulated Screw-Guided Gigli Saw - A Novel Technique

BACKGROUND

Adequate margins are technically difficult to achieve for malignant tumors involving the sacroiliac joint due to limited accessibility and viewing window. In order to address the technical difficulties faced in iliosacral tumor resection, we proposed a technique for precise osteotomy, which involved the use of canulated screws and Gigli saw (CSGS) that facilitated directional control, anteroposterior linkage of resection points and adequate surgical margins. The purpose of the current study was to evaluate whether CSGS technique facilitated sagittal osteotomy at sacral side, and were adequate surgical margins achieved? Also functional and oncological outcomes was determined along with the noteworthy complications.

METHODS

From April 2018 to November 2019, we retrospectively reviewed 15 patients who underwent resections for primary tumors of pelvis or sacrum necessitating iliosacral joint removal using the proposed CSGS technique. Chondrosarcoma was the most common diagnosis. The osteotomy site within sacrum was at ipsilateral ventral sacral foramina in 8 cases, midline of sacrum in 5 cases, and contralateral ventral sacral foramina and sacral ala with 1 case each. The average intraoperative blood loss was 3640 mL (range, 1200 and 6000 mL) with a mean operation duration of 7.4 hours (range, 5 to 12 hours). The mean follow-up was 23.0 months (range, 18 and 39 months) for alive patients.

RESULTS

Surgical margins were wide in 12 patients (80%), wide-contaminated in 1 patient (6.7%), and marginal in 2 patients (13.3%). R0 resection was achieved in 12 (80%) patients and R1 resection in 3 patients. There were three local recurrences (20%) occurred at a mean time of 11 months postoperatively. No local recurrence was observed at sacral osteotomy. The overall one-year and three-year survival rate was 86.7% and 72.7% respectively.Complications occurred in three patients.

CONCLUSIONS

The current study demonstrated that CSGS technique for tumor resection within the sacrum and pelvis was feasible and can achieve ideal resection accuracies. The use of CSGS was associated with high likelihood of negative margin resections in the current series. Intraoperative use of CSGS appeared to be technically straightforward and allowed achievement of planned surgical margins. It is worthwhile to consider the use of CSGS technique in resection of pelvic tumors with sacral invasion and iliosacral tumors, however further follow-up at mid to long-term is warranted to observe local recurrence rate.

Current Concepts in the Treatment of Giant Cell Tumors of Bone

Simple Summary

According to the 2020 World Health Organization classification, a giant cell tumor of bone is an intermediate malignant bone tumor. Denosumab treatment before curettage should be avoided due to the increased risk of local recurrence. Administration of denosumab before en bloc resection of the giant cell tumors of the pelvis and spine facilitates en bloc resection. Nerve-sparing surgery after embolization is a possible treatment for giant cell tumors of the sacrum. Denosumab therapy with or without embolization is indicated for inoperable giant cell tumors of the pelvis, spine, and sacrum. A wait-and-see approach is recommended for lung metastases at first, then denosumab should be administered to the growing lesions. Radiotherapy is not recommended owing to the risk of malignant transformation. Local recurrence after 2 years or more should be indicative of malignant transformation. This review summarizes the treatment approaches for non-malignant and malignant giant cell tumors of bone.

Abstract

The 2020 World Health Organization classification defined giant cell tumors of bone (GCTBs) as intermediate malignant tumors. Since the mutated H3F3A was found to be a specific marker for GCTB, it has become very useful in diagnosing GCTB. Curettage is the most common treatment for GCTBs. Preoperative administration of denosumab makes curettage difficult and increases the risk of local recurrence. Curettage is recommended to achieve good functional outcomes, even for local recurrence. For pathological fractures, joints should be preserved as much as possible and curettage should be attempted. Preoperative administration of denosumab for pelvic and spinal GCTBs reduces extraosseous lesions, hardens the tumor, and facilitates en bloc resection. Nerve-sparing surgery after embolization is a possible treatment for sacral GCTBS. Denosumab therapy with or without embolization is indicated for inoperable pelvic, spinal, and sacral GCTBs. It is recommended to first observe lung metastases, then administer denosumab for growing lesions. Radiotherapy is associated with a risk of malignant transformation and should be limited to cases where surgery is impossible and denosumab, zoledronic acid, or embolization is not available. Local recurrence after 2 years or more should be indicative of malignant transformation. This review summarizes the treatment approaches for non-malignant and malignant GCTBs.

Pelvic Reconstruction With a Novel Three-Dimensional-Printed, Multimodality Imaging Based Endoprosthesis Following Enneking Type I + IV Resection

BACKGROUND AND PURPOSE

Pelvic tumor involving Type I + IV resections are technically challenging, along with various reconstructions methods presenting unsatisfactory outcomes and high complication rates. Since predominating studies preferred adopting pedicle screw-rod system (PRSS) to address this issue, we designed a novel three-dimensional-printed, multimodality imaging (3DMMI) based endoprosthesis with patient-specific instrument (PSI) assistance to facilitate the surgical reconstruction of pelvic tumor involving Enneking Type I + IV resection. We aimed to investigate the clinical effectiveness of this novel endoprosthesis and compare it with PRSS in Type I + IV reconstruction.

METHODS

We retrospective studied 28 patients for a median follow-up of 47 months (range, 10 to 128 months) in this study with either 3D-printed endoprosthesis reconstruction (n = 10) or PRSS reconstruction (n = 18) between January 2000 and December 2017. Preoperative 3DMMI technique was used for tumor evaluation, PSI design, virtual surgery, and endoprosthesis fabrication. Clinical, oncological outcomes, functional assessments, and complications were analyzed between the two groups.

RESULTS

Minor surgical trauma with mean operative duration of 251 ± 52.16 minutes (p = 0.034) and median intraoperative hemorrhage of 2000ml (range, 1600, 4000ml) (p = 0.032) was observed in endoprosthesis group. Wide margins were achieved in 9 patients of the endoprosthesis group compared with 10 in the PRSS group (p = 0.09). The 1993 version of the Musculoskeletal Tumor Society score (MSTS-93) was 23.9 ± 3.76 in endoprosthesis group, which was higher than PRSS group (p = 0.012). No statistical significance was found in relapse between two groups (p = 0.36). Complications were observed in two patients in endoprosthesis group compared with 12 patients in PRSS group (p = 0.046).

CONCLUSION

The novel design of this 3D-printed endoprosthesis, together with 3DMMI and PSI assisted, is technically accessible with favorable clinical outcomes compared with PRSS. Further study is essential to identify its long-term outcomes.

Surgical Strategy of Pediatric Benign Sacral Tumors

BACKGROUND

Primary benign osseous tumors and tumor-like lesions at the sacrum are rare in the pediatric population and exact surgical strategy is still unclear. In this study, we evaluate the outcome for pediatric patients with benign tumors and tumor-like lesions at the sacrum who were receiving surgical treatment according to our proposed surgical strategy and classification.

METHODS

We analyzed 49 pediatric patients with sacral benign tumors or tumor-like lesions aged 18 years and below from 2005 to 2018. There were 23 men and 26 women with a mean age of 14.0±3.8 years. Nineteen patients had giant cell tumors (GCTs), 9 aneurysmal bone cysts, 5 osteoblastomas, 5 neurogenic tumors, 3 hemangiomas, 3 teratomas, 2 Langerhans cell histiocytosis, 1 chondroblastoma, 1 fibrous dysplasia, and 1 GCT of tendon sheath. We proposed our surgical plan and surgical classification for pediatric patients with sacral benign tumors or tumor-like lesions.

RESULTS

The mean follow-up duration was 6.2 years (range, 1.0 to 18.9 y). GCTs (39%, 19/49) and primary aneurysmal bone cysts (18%, 9/49) are the top 2 common histologic types. Preoperative selective arterial embolization (SAE) was performed in 12 cases and 24 patients received intraoperative aortic balloon occlusion (ABO) as the preoperative surgical plan. Furthermore, according to tumor location at the sacrum, we classified surgical excision of sacral benign tumors and tumor-like lesions into 3 types. Fourteen cases were classified as type I, 27 as type II, 3 as type III, and 5 patients with neurogenic tumors cannot be classified into this surgical classification. Ten patients had wound complications. Two had femoral artery thrombosis because of ABO application. One had mechanical failure. Rate of local recurrence was 16%. Seven patients with GCTs and 1 with neurogenic tumor had local recurrence. No patient died of disease at the last follow-up. For the assessment of neurological function, the rate of neurological dysfunction was 12% (6/49). Four cases had urinary incontinence, 3 fecal incontinence, and 3 had bowel obstruction. Next, univariate analysis for influence of preoperative SAE and intraoperative ABO on complications demonstrated that both of them exerted no significant influence on the occurrence of oncological and nononcological complications.

CONCLUSIONS

The proposed surgical strategy can provide an excellent therapeutic effect for pediatric benign tumors and tumor-like lesions at the sacrum. Preoperative SAE and intraoperative ABO can safeguard pediatric patients with high vascularity of benign tumor at the sacrum during the operation.

LEVEL OF EVIDENCE

Level IV.

Pelvic exenteration: Pre-, intra-, and post-operative considerations

This review outlines the role of pelvic exenteration (PE) in the management of certain locally-advanced primary and recurrent rectal cancers. PE has undergone significant evolution over the past decades. Advances in pre-, intra-, and post-operative care have been directed towards achieving the 'holy grail' of an R0 resection, which remains the most important predictor of survival, quality of life, morbidity, and cost effectiveness following PE. Patient selection for surgery is largely determined by assessment of resectability. Pelvic magnetic resonance imaging determines the extent of local disease, while positron emission tomography remains the most accurate tool for exclusion of distant metastases. PE in the setting of metastatic disease or with palliative intent remains controversial. The intra-operative approach is based on the anatomical division of the pelvis into five compartments (anterior, central, posterior, and two lateral). Within each compartment are various possible dissection planes which are elected depending on the extent of tumour involvement. Innovations in surgical technique have allowed 'higher and wider' dissection planes with resultant en bloc excision of major vessels, major nerves, and bone. Evidence of improved R0 resection and survival rates with these techniques justifies the radicality of these novel approaches. Post-operative care for PE patients is technically demanding with a substantial hospital resource burden. Unique considerations for PE patients include the 'empty pelvis syndrome', urological complications, and management of post-operative malnutrition. While undeniably a morbid procedure, quality of life largely returns to baseline at six months, and for long-term survivors is sustained for up to five years.

Prolonged balloon occlusion of the lower abdominal aorta during pelvic or sacral tumor resection

Background

To explore the efficacy of lower abdominal aorta balloon occlusion technology in pelvis and sacral tumor surgery and to assess the safety of prolonged balloon occlusion.

Methods

From January 2008 to January 2017, 81 patients were diagnosed with sacrum or pelvic tumor and underwent surgery in our institution. Balloon catheters were placed through the femoral artery to occlude the abdominal aorta of the pelvic tumor and sacrum region undergoing tumor resection. These patients were divided into two group based on single balloon blocking time. Group A had a balloon blocking time of 60 minutes or less, and group B had a balloon occlusion time greater than 60 minutes. The patients in the two groups were compared with regards to operation time, intraoperative blood loss, blood transfusion volume, average length of hospital stay, and postoperative complications.

Results

No balloon displacement or leakage of the abdominal aorta occurred during the operations. The difference in operation time between the two groups was statistically significant (P≤0.05), and the differences in intraoperative blood loss, blood transfusion volume, and average hospital stay between groups A and B were not significant (P>0.05). The incidence of postoperative complications was 12% in group A, and 22.6% in group B, with no statistically significant differences (P>0.05).

Conclusions

Prolonged balloon occlusion was safe and effective in the surgical treatment of complicated pelvic and sacral tumors. It did not increase the incidence of postoperative complications such as distal limb paralysis, arterial thrombosis, or ischemic necrosis.

Analysis of clinical outcome for adolescent patients undergoing conservative nerve-sparing surgery based on the proposed resection classification for sacral giant cell tumor

The most common of age distribution ranges from second to fourth decade of life and patients with giant cell tumors (GCT) aged less than 18 years is more uncommon. We are aiming to reveal what the conservative nerve-sparing surgery values for adolescent patients with sacral GCT. We retrospectively reviewed 15 adolescent patients with sacral GCT aged <eighteen years, who received the conservative nerve-sparing surgery at our center from 2007 to 2018. Four patients presented with tumor of Campanacci grade II and 11 patients with grade III. According to the location of tumor at the sacrum, we classified the surgical resection of sacral giant cell tumor into three types. In our adolescent cohort, nine had the aortic balloon occlusion and five received the selective arterial embolization. All patients were free of disease and no one had the pulmonary metastasis or died of disease. All five wound complications required the debridement. 6 out of 15 patients had the local recurrence that required surgery treatment. The average time to recurrence after initial surgery in the present adolescent cohort was 22.4 months. Two patients had the surgical site infection and three had the wound dehiscence. One had the femoral artery thrombosis due to the aortic balloon occlusion and received the surgical removal of thrombosis. With the help of preoperative selective embolization and intraoperative aortic balloon occlusion, adolescent patients undergoing conservative nerve-sparing surgery for giant cell tumor of sacrum based on the proposed surgical resection classification have an acceptable clinical outcome and neurologic function.

Patient-Specific Three-Dimensional Model for a Safe Surgical Pathway in Sacral Chondrosarcoma

Sacral tumors are amongst the most challenging procedures to treat because of the complex anatomy. This study determined whether patient-specific models change preoperative planning decisions made in preparation for en bloc resection of complex sacral mass surgical procedures. Imaging showed a big encapsulated mass at the S2-3 level involving the neural foramina and obscuring the nerve roots. High-resolution images were acquired and utilized to generate a patient-specific 3D tumor model. The visual and tactile inspection of 3D models allowed the best anatomical understanding, with faster and clearer comprehension of the surgical anatomy. The 3D sacral model was for observation of previously unapparent anatomical details; with this new technology, surgeon can observe their planned surgical intervention, explore the patient-specific anatomy and extension of the tumor, and sharpen their procedure choices. Moreover, multiple planes showed how far the angles on the plane would extend for osteotomy of the sacrum. Another result was identifying correct guides and safe venture landmarks. The study helped to establish safe osteotomy line wherever the nerve roots were retained and enabled osteotomy by preserving bilaterally the S1 and S2 nerve roots for wide excision of wide excision of primary sacral tumor to get adequate bowel and bladder functions. Finally, it helped to determine whether or not the remaining bone in the sacrum is sufficient for spinopelvic stability and needed fixation. It was decided spinopelvic fixation was not necessary for this case. Surgical intervention of sacral tumors varies depending on the tumor, its size, extension, and location. Surgery can have profound risks including unnecessary nerve root resection spinopelvic instability and suboptimal oncological resection. 3D models help to transfer complex anatomical information to clinicians and provide guidance in the preoperative planning stage, for intraoperative navigation and for surgical training purposes.

En bloc resection of pelvic sarcomas with sacral invasion: a classification of surgical approaches and outcomes

Aims

The sacrum is frequently invaded by a pelvic tumour. The aim of this study was to review our experience of treating this group of patients and to identify the feasibility of a new surgical classification in the management of these tumours.

Patients and Methods

We reviewed 141 patients who, between 2005 and 2014, had undergone surgical excision of a pelvic tumour with invasion of the sacrum. In a new classification, pelvisacral (Ps) I, II, and III resections refer to a sagittal osteotomy through the ipsilateral wing of the sacrum, through the sacral midline, or lateral to the contralateral sacral foramina, respectively. A Ps a resection describes a pelvic osteotomy through the ilium and a Ps b resection describes a concurrent resection of the acetabulum with osteotomies performed through the pubis and ischium or the pubic symphysis. Within each type, surgical approaches were standardized to guide resection of the tumour.

Results

The mean operating time was 5.2 hours (sd 1.7) and the mean intraoperative blood loss was 1895 ml (sd 1070). Adequate margins were achieved in 112 (79.4%) of 141 patients. Nonetheless, 30 patients (21.3%) had local recurrence. The mean Musculoskeletal Tumor Society (MSTS93) lower-limb function score was 68% (sd 19; 17 to 100). According to the proposed classification, 92 patients (65%) underwent a Ps I resection, 33 patients (23%) a Ps II resection, and 16 (11%) patients a Ps III resection. Overall, 82 (58%) patients underwent a Ps a resection and 59 (42%) patient a Ps b resections. The new classification predicted surgical outcome.

Conclusion

We propose a comprehensive classification of surgical approaches for tumours of the pelvis with sacral invasion. Analysis showed that this classification helped in the surgical management of such patients and had predictive value for surgical outcomes. Cite this article: Bone Joint J 2018;100-B:798-805.

Pelvic Exenteration Surgery: The Evolution of Radical Surgical Techniques for Advanced and Recurrent Pelvic Malignancy

Pelvic exenteration was first described by Alexander Brunschwig in 1948 in New York as a palliative procedure for recurrent carcinoma of the cervix. Because of initially high rates of morbidity and mortality, the practice of this ultraradical operation was largely confined to a small number of American centers for most of the 20 century. The post-World War II era saw advances in anaesthesia, blood transfusion, and intensive care medicine that would facilitate the evolution of more radical and heroic abdominal and pelvic surgery. In the last 3 decades, pelvic exenteration has continued to evolve into one of the most important treatments for locally advanced and recurrent rectal cancer. This review aimed to explore the evolution of pelvic exenteration surgery and to identify the pioneering surgeons, seminal articles, and novel techniques that have led to its current status as the procedure of choice for locally advanced and recurrent rectal cancer.

Sacral Reconstruction with a 3D-Printed Implant after Hemisacrectomy in a Patient with Sacral Osteosarcoma: 1-Year Follow-Up Result

Pelvic reconstruction after sacral resection is challenging in terms of anatomical complexity, excessive loadbearing, and wide defects. Nevertheless, the technological development of 3D-printed implants enables us to overcome these difficulties. Here, we present a case of sacral osteosarcoma surgically treated with hemisacrectomy and sacral reconstruction using a 3D-printed implant. The implant was printed as a customized titanium prosthesis from a 3D real-sized reconstruction of a patient's CT images. It consisted mostly of a porous mesh and incorporated a dense strut. After 3-months of neoadjuvant chemotherapy, the patient underwent hemisacretomy with preservation of contralateral sacral nerves. The implant was anatomically installed on the defect and fixed with a screw-rod system up to the level of L3. Postoperative pain was significantly low and the patient recovered sufficiently to walk as early as 2 weeks postoperatively. The patient showed left-side foot drop only, without loss of sphincter function. In 1-year follow-up CT, excellent bony fusion was noticed. To our knowledge, this is the first report of a case of hemisacral reconstruction using a custom-made 3D-printed implant. We believe that this technique can be applied to spinal reconstructions after a partial or complete spondylectomy in a wide variety of spinal diseases.

Hemisacrectomy with preservation of the contralateral sacral nerve roots and sacroiliac joint for pelvic neurofibrosarcoma in a 7-year-old child: case report with 2-year follow-up

Neurofibrosarcoma is rare in the pediatric age group. A malignant tumor of the sacrum presents significant challenges, especially if the goals are to resect with wide and clean surgical margins and to achieve acceptable functional outcomes. The authors report a case of this rare tumor affecting the sacrum and sacral nerve roots of a 7-year-old girl and review the role of total hemisacrectomy sparing the contralateral sacral nerve roots and lumbopelvic reconstruction in the treatment of this disease. This patient is, to the best of the authors' knowledge, the youngest to be treated in this manner.

Malignant Pelvic Tumors Involving the Sacrum: Surgical Approaches and Procedures Based on a New Classification

OBJECTIVE

To introduce a new classification of Enneking type IV pelvic tumors involving the sacrum and a corresponding system of standardized surgical approaches and procedures for resection of such tumors, and to investigate the feasibility and therapeutic effect of the new system.

METHODS

Data on 59 patients treated between February 2003 and February 2013 by standardized surgical approaches and procedures were retrospectively reviewed. The study subjects comprised 28 male and 31 female patients with a mean age at diagnosis of 36 years (range, 2-72 years). There are four subtypes in the new classification: (i) subtype IVa, neoplasms invading the ipsilateral sacral wing; (ii) subtype IVb, neoplasms invading the ipsilateral sacral foramina; (iii) subtype IVc, neoplasms invading the contralateral sacral foramina; and (iv) subtype IVd, neoplasms invading the whole of the sacrum. Standardized surgical approaches and procedures were devised for en-bloc resection for each subtype with adequate margins.

RESULTS

Adequate margins were achieved in 43/59 patients (72.9%). The mean operation time was 5.0 h and the mean intraoperative blood loss 2157 mL. At the final follow-up, 27/53 patients (50.9%) who had been followed up were alive and in complete remission. The mean Musculoskeletal Tumor Society 93 score was 17.4 (58%) of a possible 30 points. The mean functional score for patients who had undergone a pelvic zone II resection was 15.2, compared with 19.0 for those with an intact pelvic zone II.

CONCLUSIONS

The proposed standardized protocols should help orthopaedic surgeons to achieve adequate margins, manage risk, achieve better oncologic and functional outcomes, and minimize perioperative complications when treating massive pelvic tumors involving the sacrum.

Residual neurological function after sacral root resection during en-bloc sacrectomy: a systematic review

PURPOSE

Sacrectomy is a highly demanding surgery representing the main treatment for primary tumors arising in the sacrum and pelvis. Unfortunately, it is correlated with loss of important function depending on the resection level and nerve roots sacrificed. The current literature regarding residual function after sacral resection comes from several small case series. The goal of this review is to appraise residual motor function and gait, sensitivity, bladder, bowel, and sexual function after sacrectomies, with consideration to the specific roots sacrificed.

METHODS

An exhaustive literature search was conducted. All manuscripts published before May 2015 regarding residual function after sacrectomy were considered; if a clear correlation between root level and functioning was not present, the paper was excluded. The review identified 15 retrospective case series, totaling 244 patients; 42 patients underwent sacrectomies sparing L4/L4, L4/L5 and L5/L5; 45 sparing both L5 and one or both S1 roots; 8 sparing both S1 and one S2; 48 sparing both S2; 11 sparing both S2 and one S3, 54 sparing both S3, 9 sparing both S3 and one or both S4, and 27 underwent unilateral variable resection.

RESULTS

Patients who underwent a sacrectomy maintained functionally normal ambulation in 56.2 % of cases when both S2 roots were spared, 94.1 % when both S3 were spared, and in 100 % of more distal resections. Normal bladder and bowel function were not present when both S2 were cut. When one S2 root was spared, normal bladder function was present in 25 % of cases; when both S2 were spared, 39.9 %; when one S3 was spared, 72.7 %; and when both S3 were spared, 83.3 %. Abnormal bowel function was present in 12.5 % of cases when both S1 and one S2 were spared; in 50.0 % of cases when both S2 were spared; and in 70 % of cases when one S3 was spared; if both S3 were spared, bowel function was normal in 94 % of cases. When even one S4 root was spared, normal bladder and bowel function were present in 100 % of cases. Unilateral sacral nerve root resection preserved normal bladder function in 75 % of cases and normal bowel function in 82.6 % of cases. Motor function depended on S1 root involvement.

CONCLUSION

Total sacrectomy is associated with compromising important motor, bladder, bowel, sensitivity, and sexual function. Residual motor function is dependent on sparing L5 and S1 nerve roots. Bladder and bowel function is consistently compromised in higher sacrectomies; nevertheless, the probability of maintaining sufficient function increases progressively with the roots spared, especially when S3 nerve roots are spared. Unilateral resection is usually associated with more normal function. To the best of our knowledge, this is the first comprehensive literature review to analyze published reports of residual sacral nerve root function after sacrectomy.