Hindquarter amputations for bone or soft tissue sarcoma cause a high degree of disability in patients and are associated with high morbidity rates. The goal of this study is to determine prognostic factors for outcome and analyse quality of life after resection, in order to better select patients who are more likely to benefit from a hindquarter amputation. Our prospectively collected database was searched for all patients treated with a hindquarter amputation between 1989 and 2015. Clinical and histopathological features were analysed for their prognostic value using Kaplan-Meier and Cox proportional hazard analysis. Endpoints were set at recurrent disease and death. Also, functional and social outcome as well as pain was assessed from the hospital charts in the patients that are still alive. 82 patients underwent a hindquarter resection in the given time frame. Of these patients, 63 were treated with a curative intent. The median hospital stay was 25 days, and 49% of the patients had wound complications. The in-hospital mortality was 6%. The 5-year overall survival in the whole group was 31%, while disease free survival was 26%. As expected, patients with metastases at presentation had a significantly worse outcome, while patients with locally recurrent sarcoma had the same outcome as patients with primary sarcoma. For those patients treated with curative intent, younger age was correlated with better survival, while higher histological grade was correlated with worse disease free survival. The functional and social outcome for patients who survived more then one year varied widely, with about 50% of the patients living an acceptable social life with reasonable pain levels and mobility status. Hindquarter amputations for sarcoma patients are still indicated for a select group of patients. Younger patients and/or patients with low grade sarcomas are more likely to benefit form this resection in terms of survival and long term function. However, for patients with less favourable prognostic factors a hindquarter operation might be an unreasonable palliative option

Background: Advances in adjuvant and neoadjuvant therapies have rendered many tumours that previously necessitated amputation amenable to limb salvage procedures. However, a significant proportion of tumours are still treated by hindquarter amputation in an attempt to cure the patient, or to reduce the tumour load. This tends to be lengthy, mutilating and is associated with high morbidity and poor survivorship. Aims: To review the survivorship, quality of life and functional assessment following hindquarter amputations performed in this centre in the last 10 years. Methods: This was a retrospective study of 51 consecutive patients who had hindquarter amputations for tumours between 1996 to 2006. Available patients were evaluated using contemporary functional outcome assessments (Musculoskeletal Society Tumour Score, Toronto Extremity Salvage Score, SF36). Results: Fifty-one patients (31 males, 20 females) had palliative(8) or curative hindquarter amputations(43) for Chondrosarcoma(18), Malignant Fibrous Histiocytoma(6), Osteosarcoma(4) and other sarcoma sub-types(23). The mean age was 50.7 years (range 24–78). The mean duration of symptoms until referral was 5.2 months, the mean time from referral to tissue diagnosis was 16.2 days (range 2–80) and the time from confirmed histological diagnosis to surgery was 39.2 days (range 2–190) on average. Significant complications included phantom limb pain(15), wound problems(24), urinary problems(6), cardiopulmonary events(5) and erectile dysfunction(3). 33 of the 51 patients have passed away, with a mean survival postoperatively of 10.7 months (range 2–43), with carcinomatosis the main cause of death. The mean cumulative survival following hindquarter amputation in this hospital is 17.3 months. Conclusions: Patients with no metastasis and clear margins at amputation had a better cumulative survival rate. Therefore the decision to proceed for hindquarter amputation to achieve a curative resection is justified but has to be weighed up against the associated significant complications, morbidity and functional deterioration

Survival in the wake of hindquarter amputation and oncological treatment is improving; the hindquarter amputee population is increasing. Some amputees function well, others do not. To assess quality of life and function of hindquarter amputees. 21 amputees (10 females and 11 males) consented to take part in the study. Ethics approval was sought. Assessment was performed using postal questionnaires; SF36 for quality of life; TESS (Toronto Extremity Salvage Score) for physical function and mobility; IEFF( International Index for Erectile Function) for male sexual function; a prosthetics questionnaire to assess prosthetic use. Mean age of the group was 55 with the mean survival of 7 years post amputation. Quality of life results were compared to normal subjects and patients for long term illness. Amputees had a significant reduction in quality of life concerning physical function and pain. Social function, mental health and energy levels were equivalent to patients with long term illness. The mean TESS result was 56.9 with females having a mean score of 61.7 and male of 48. 50% of the group considered themselves as severely to completely disabled; 50% considered themselves moderately disabled. Five were in full time employment. Six males responded to the sexual function questionnaire. Impotence was universally experienced. Only five amputees used their prosthesis regularly. All amputees have experienced and 20 continue to experience phantom pain. This study illustrates that hind quarter amputees have poor physical function and a low quality of life. Phantom pain is universally experienced. Male amputees experience impotence. Addressing these areas would improve the life of current and future hind quarter amputees

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

Skeletal tuberculosis is an indolent disease whose diagnosis is often delayed. Evidence of pulmonary tuberculosis is present in less than 50% of cases. We present our experience from a small inner city district hospital of the difficulties managing patients with skeletal tuberculosis. During the period 1988 to 1998 a total of 38 patients with tuberculous osteomyelitis confirmed microbiologically by tissue culture or histologically on material gained at biopsy presented to our inner city hospital serving 250 000 patients. Two groups of patients were identified in our series. There was an acute group that tended to affect the appendicular skeleton and who responded to local treatment plus chemotherapy with restoration of normal function. In contrast the second group, who were difficult to diagnose, had axial skeleton involvement, deteriorated before treatment and had a poor outcome despite treatment. Failure of admitting medical teams to examine the axial skeleton in their confused patients led to a delay in diagnosis of skeletal tuberculosis in this second group with profound consequences. All health professionals will be encountering skeletal tuberculosis more frequently with the recent resurgence of pulmonary tuberculosis. They may have little experience with the management of this condition and may overlook the diagnosis with consequent catastrophic results. A high index of suspicion is required for prompt diagnosis with early referral to an orthopaedic surgeon improving outcome. Survival in the wake of hindquarter amputation and oncological treatment is improving; the hindquarter amputee population is increasing. Some amputees function well others do not. To assess quality of life and function of hindquarter amputees. 21 amputees (10 females and 11 males) consented to take part in the study. Ethics approval was sought. Assessment was performed using postal questionnaires; SF36 for quality of life; TESS (Toronto Extremity Salvage Score) for physical function and mobility; IEFF( International Index for Erectile Function) for male sexual function; a prosthetics questionnaire to assess prosthetic use. Mean age of the group was 55 with the mean survival of 7 years post amputation. Quality of life results were compared to normal subjects and patients for long tern illness. Amputees had a significant reduction in quality of life concerning physical function and pain. Social function, mental health and energy levels were equivalent to patients with long term illness. The mean TESS result was 56.9 with females having a mean score of 61.7 and male of 48. 50% of the group considered themselves as severely to completely disabled; 50% considered themselves moderately disabled. Five were in full time employment. Six males responded to the sexual function questionnaire. Impotence was universally experienced. Only five amputees used their prosthesis regularly. All amputees have experienced and 20 continue to experience phantom pain. This study illustrates that hindquarter amputees have poor physical function and a low quality of life. Phantom pain is universally experienced. Male amputees experience impotence. Addressing these areas would improve the life of current and future hindquarter amputees

The April 2013 Oncology Roundup. 360 . looks at: the margin for error; new money for old risks; hindquarter amputation; custom tumour jigs; preserving the tibial epiphysis; how long is long enough?; genomics and radiation-induced bone tumours; and India ink

Purpose: Resection of pelvic sarcoma with limb preservation (internal hemipelvectomy) is a major undertaking. Resection requires large areas of soft-tissue to be removed. Because of wound complications, we manage these defects with immediate tissue transfer (ITT) at the time of resection when a large defect is anticipated. This study compares the outcomes of ITT with primary wound closure (PWC). Method: Twenty patients undergoing 22 separate procedures (1995–2007) were identified in our prospectively maintained database. Demographics, tumour type, operative data and complications, and functional scores (MSTS-1993, TESS) were collected. Results: Twelve defects were managed with ITT, nine with pedicled myocutaneous vertical rectus abdominis (VRAM) flaps (one received double VRAM flaps due to the large defect), two with tensor fascia lata (TFL) rotation flaps (one augmented by local V-Y advancement, the other with gluteus maximus rotation flap) and one received latissimus dorsi free tissue transfer. Four wound complications necessitated operative intervention in this group: two debrided VRAM flaps went on to heal and the two TFL flaps required revision: one to VRAM flap and the other to a latissimus dorsi free flap which ultimately suffered chronic infection and hindquarter amputation was performed. Ten defects were managed with PWC, and 5 wound complications occurred, all five suffered infection, one developed hematoma and one dehisced. One wound resolved with debridement, two healed after revision to pedicled gracilis and gluteus maximus myocutaneous flaps. Two patients were converted to hindquarter amputation due to chronic infection. Functional scores were collected on 8 of 12 living patients, at time of writing. The mean TESS scores were 83 and 73 in the ITT and PWC groups. Five patients in the ITT and 3 in the PWC group were deceased. Conclusion: Soft-tissue closure following pelvic sarcoma resection remains a difficult challenge, and our experience reflects that. There were fewer wound complications (33% v 50%) and slightly better function with ITT than PWC, but this was not statistically significant due to the small size of our study. Although small, this study suggests ITT should be considered whenever a large soft tissue defect is anticipated

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.

Introduction. The success of total hip replacement in the young has consistently been worse both radiologically and clinically when compared to the standard hip replacement population. Methods. We describe the clinical and radiological outcome of 58 consecutive polished tapered stems (PTS) in 47 patients with a minimum of 10 years follow-up (mean 12 years 6 months) and compared this to our cohort of standard patients. There were 22 CPT stems and 36 Exeter stems. Results. Three patients with 4 hips died before 10 years and one hip was removed as part of a hindquarter amputation due to vascular disease. None of these stems had been revised or shown any signs of failure at their last follow-up. No stems were lost to follow-up and the fate of all stems is known. Survivorship with revision of the femoral component for aseptic loosening as the endpoint was zero and 4% (2 stems) for potential revision. The Harris hip scores were good or excellent in 81% of the patients (mean score 86). All the stems subsided within the cement to a mean total of 1.8mm (0.2-8) at final review. There was excellent preservation of proximal bone and an extremely low incidence of loosening at the cement bone interface. Cup failure and cup wear with an associated periarticular osteolysis was a serious problem. 19% of the cups (10) were revised and 25% of the hips (13) had significant periarticular osteolysis associated with excessive polyethylene wear. Discussion. The outcome of polished tapered stems in this age group is as good as in the standard age group and superior to other non PTS designs in young patients. This is despite higher weight and frequent previous surgery. Cup wear and cup failure were significantly worse in this group, with a higher incidence of periarticular osteolysis

Aim: To identify tumour and treatment factors significant for both local control and survival for patients with chondrosarcoma of the pelvis. Method: The features of all patients with non metastatic chondrosarcoma of the pelvis treated at a tertiary treatment centre between 1971 and 2001 with more than 2 years of follow-up were analyzed. Results: There were 106 patients with a median age of 44. There were equal numbers of male and female patients in the group. The median size of the tumours was 12cm. 47 tumours were grade 1, 37 were grade 2 and 22 were grade 3. Treatment involved hindquarter amputation in 33 and excision with or without reconstruction in 73. Clear margins (wide or better) were achieved in 34 cases. The excision was marginal in 30 cases and intralesional or contaminated in 37. Local recurrence arose in 39 patients and was related to adequate margins of excision (p=0.03) and grade (p=0.01). Overall survival was 72% at 5 years, 56% at 10 years and 46% at 15 years. Survival was strongly related to grade (p=0.08) but survival beyond 5 years was most strongly related to the adequacy of the excision margins. Conclusion: Tumour grade is the most important prognostic factor for chondrosarcoma of the pelvis but the ability to obtain clear margins of excision influences both local control and the prospects for long term survival

Introduction: Renal cell carcinoma often metastasizes to the skeleton and less frequently soft tissues, leading to the increased risk of fracture. Previous studies have show that the survival of patients with bone metastases is frequently prolonged and that early failure of surgical implants designed for fracture fixation is high. The aim of the study was to investigate the outcomes from surgical procedures undertaken at a tertiary referral bone tumour unit. Methods: A retrospective review of consecutive patients presenting with a musculoskeletal metastasis to our unit from October 1976 to June 2007 was undertaken. There were 179 patients seen over this period, 89 with solitary and 90 with multiple mets. The mean age at presentation was 60.0 yrs. The mean follow up was 16.9 months. Kaplan-Meyer implant and patient survival analysis was undertaken. Results: The mean patient survival was 22 months (range 1 month to 16 years). The 1yr, 3yr and 10yr patient survival was 77 %, 44 % and 11 % respectively. The types of surgical treatment undertaken included EPR in 119 patients, conventional arthroplasty in 15 patients, fracture fixation in 14 patients, excision only in 12 patients, amputation in 9 patients, curettage and cementation in 9 patients, decompression stabilization of spine in 1 patient. Two femoral EPRs failed due to infection, requiring hindquarter amputations. Failure of fixation to the humerous lead to a forequarter amputation, two hip dislocations. Failure of curettage and cementation in the acetabulum and proximal tibia were treated with THR and EPR respectively. Discussion: Patients with renal cell carcinoma metastases can survive for prolonged periods. Any surgical intervention for bone metastases has to outlive the patient and EPRs are reliable with a low rate of failure or complication. We would recommend resection and reconstruction with endoprostheses for solitary renal metastases in a tertiary referral unit

We aim to establish the likely functional scores following different types of surgery for bone tumours. All living patients who had undergone treatment for a bone tumour were contacted and invited to complete a TESS self-report questionnaire. The TESS contains 32 items of day-to-day activities which the patient scores themselves against. The final score is a percentage, with 100% being ‘normal’. The project was approved by the local ethical committee. 723 responses were obtained from just over 1000 letters that were sent. Thirty seven sets of data were incomplete leaving a total of 686. There were 369 males and 317 females, with an average age of 49 (range 15 to 93). The mean interval from their initial operation was 12 years (range 1 to 42). 590 of the procedures were in the lower limb and 96 in the upper limb. 126 patients had an amputation and 560 limb salvage (82%). Mean scores obtained for each procedure were: EPR mid-femur 86%; EPR distal femur 77%; EPR proximal tibia 74%; EPR proximal humerus 71%; EPR proximal femur 71%; Below knee amputation 70%; EPR total femur 63%; Disarticulation of the hip 61%; Above knee amputation 60%; Hindquarter amputation 57%; EPR pelvis 54%. Younger patients had much better scores (80% for those under 30 vs. 69% for those over 30, p< 0.0001) than those over 30. Additionally, the scores for those that had had an amputation following a EPR procedure were no worse than those who had had an amputation originally. Significantly, EPR proximal tibia was better than AKA (78% vs. 67% p = 0.0003), as was EPR distal femur (80% vs. 67% p < 0.0001). This data from a large series is helpful in indicating likely outcomes following surgical treatment of sarcomas, both for patients and surgeons

The success of total hip replacement in the young has consistently been worse both radiologically and clinically when compared to the standard hip replacement population. Methods: We describe the clinical and radiological outcome of 58 consecutive polished tapered stems (PTS) in 47 patients with a minimum of 10 years follow up (mean 12 years 6 months) and compared this to our cohort of standard patients. There were 22 CPT stems and 36 Exeter stems. Results: Three patients with 4 hips died before 10 years and one hip was removed as part of a hindquarter amputation due to vascular disease. None of these stems had been revised or shown any signs of failure at their last follow-up. No stems were lost to follow up and the fate of all stems is known. Survivorship with revision of the femoral component for aseptic loosening as the endpoint was zero and 4% (2 stems) for potential revision. The Harris hip scores were good or excellent in 81% of the patients (mean score 86). All the stems subsided within the cement to a mean total of 1.8mm (0.2–8) at final review. There was excellent preservation of proximal bone and an extremely low incidence of loosening at the cement bone interface. Cup failure and cup wear with an associated periarticular osteolysis was a serious problem. 19% of the cups (10) were revised and 25% of the hips (13) had significant periarticular osteolysis associated with excessive polyethylene wear. Discussion: The outcome of polished tapered stems in this age group is as good as in the standard age group and superior to other non PTS designs in young patients. This is despite higher weight and frequent previous surgery. Cup wear and cup failure were significantly worse in this group, with a higher incidence of periarticular osteolysis

Purpose: We report a series of patients with malignant tumours of the pelvis that had a tissue expander inserted in the pelvis to facilitate radical radiotherapy, and report functional outcomes following treatment. Introduction: Surgery for malignant tumours affecting the pelvis is challenging. Some tumours are suitable for internal hemipelvectomy and reconstruction, some require hindquarter amputation and some are inoperable. Overall prognosis is poor with high morbidity and mortality rates. There may be a place for alternative treatment with the insertion of pelvic spacers to facilitate radical radiotherapy. This is indicated in patients who have an inoperable tumour, who decline amputation, or who had an internal hemipelvectomy with close margins and high risk of local recurrence. Methods & Results: We performed a retrospective review of all patients who presented with a malignant tumour of the pelvis and who underwent an insertion of a pelvic spacer followed by local high dose radiotherapy. Available patients were followed up and evaluated using the Musculoskeletal Society Tumour Score (MSTS) and the Toronto Extremity Salvage Score (TESS). There were ten patients; 5 had Ewing’s sarcoma, 3 had osteosarcoma, 1 had spindle cell sarcoma and 1 had alveolar soft part sarcoma. 4 patients had metastases on presentation. The average age was 30 years (14 to 56 years), and average follow-up was 15 months (12 to 24 months). 4 patients died and 6 are still alive. There were no surgical complications. The average length of hospital stay was 6 days (2 to 10 days). Patients averaged an MSTS score of 63% and a TESS of 67%. Conclusion: Radical radiotherapy after spacer insertion offers an alternative to morbid surgery and is associated with good functional outcomes

Reconstruction following internal hemipelvectomy for bone tumors remains a major surgical challenge. Most of the cases are considered not suitable for reconstruction because of high complication occurrence. Allografts coupled with standard prosthesis is a reliable method of reconstruction. 26 patients received a McMinn stemmed cup (Link, Germany) after periacetabular tumor resection from February 1999 to 2006. In 18 patients the reconstruction followed resection of the acetabular area while in other 8 an extrarticular resection of the proximal femur was performed. In 21 cases a stemmed acetabular cup were associated with massive bone allograft. There were 13 female and 13 male with a mean age of 41 years (13 to 70). Average follow-up was 45 months (7 to 105). Six patients were affected by local recurrence of the tumour and five underwent hindquarter amputation. In 4 of them the index surgery followed a previous recurrence of the tumour. Finally 6 patients died for related causes within 2 years. All the other 20 have been followed clinically and radiographically for a minimum of 24 months. Deep infection occurred in one case, there were no cases of dislocation. Radiolucency at the prosthesis-bone interface was observed in 3 cases, 2 patients had proximal migration < of 20 mm. Only one patient was treated for aseptic loosening because of incorrect initial position of the implant. The iliac osteotomy was consolidated in all cases, while a delayed union was frequently observed in the pubic osteotomy, however without compromise the stability of implant. Functional result were evaluated according to the MSTS system and this showed 65% of excellent or good clinical results. The procedure requires appropriate patient selection, accurate preoperative planning, meticulous selection and preparation of allograft. Usually artificial ligaments are applied to reduce hip instability, however, this type of reconstruction do not require complex fixation, thus reducing surgical time and early complications

This retrospective clinical study describes our experience of the use of growing endoprostheses in children with primary malignant tumours of the proximal femur and analyses the results. Between 1983 and 1996 we treated nine children with primary bone tumors of the proximal femur by resection and proximal femoral extensible replacements. Outcomes measured were function of the limb using Musculoskeletal Tumor Society score, oncologic outcome, complications and equalization of limb length. Results: Four patients died as a result of pulmonary metastases. The remaining five patients were observed for an average follow-up period of 7. 6 years (range 11–12. 7 years). One patient had a hindquarter amputation for uncontrolled infection. In these five patients we performed an average of 10. 2 operative procedures per patient (range of 3–17 procedures) including 5 lengthening procedures (range of 1–8 procedures) and a mean total extension of 69. 7 mm per patient. Acetabular loosening and hip dislocations were the most frequent complications. Only two patients have not had a revision or a major complication. Despite this, 4 children are alive with a functioning lower limb and a mean Musculoskeletal Tumour Society functional score of 77. 6%. The limb length discrepancy was less than 1 0 mm in three of these patients. The remaining patient has a discrepancy of 50 mm and is awaiting further limb equalization procedures. Extendible endoprostheses of the proximal femur in selected children is a viable reconstructive procedure. It allows for equalization of limb length and the ability to walk without the use of mobility aids

99 patients with new diagnosed soft tissue sarcomas involving the pelvic region were studied to determine the outcome and prognostic factors for survival and local recurrence. The mean age at diagnosis was 57 years. There were 55 males and 44 females. The mean tumor size was 12cm. The tumor was deep in 79 patients and superficial in 20. Surgical treatment was excision in 93 patients and hindquarter amputation in 6 patients. Histological grade was low grade in 23 and high grade in 75 patients. 7% of the patients had metastases at presentation. The 5 year overall survival was 57% and local recurrence occurred in 22% of the patients. The risk of inadequate surgical margins in patients with tumors within the pelvic brim was 50% compared to 18% for those with tumors located outside the pelvic brim. The significant predictors of local recurrence were inadequate margins and location of the tumor within the pelvic brim. Tumor size, grade and depth did not influence development of local recurrence. Significant predictors of survival included metastases at presentation, tumor grade and depth. The cumulative 5 year survival for patients with deep high grade tumors, deep low grade tumors, superficial high grade and superficial low grade tumors were 45%, 74%, 63% and 100% respectively (p=0.01). The 5-year overall survival was 66% in those patients without local recurrence compared to 37% in those who develop local recurrence (p=0.005). Multivariate analysis revealed that development of local recurrence was the most important determinant of overall and metastases free survival. We conclude that patients with pelvic soft tissue sarcoma who develop local recurrence have an extremely poor prognosis. Patients with high grade and inadequate surgical margins represent a particular group with very high risk of metastases and death even with radiotherapy and perhaps should be considered for other adjuvant treatment

Introduction and Aims: Resection of large pelvic bone tumors often results in segmental defects with pelvic discontinuity and loss of the acetabulum. We reviewed the functional and oncologic outcomes following pelvic allograft and total hip arthroplasty (THA) reconstruction. Method: A retrospective review of our prospectively collected database was undertaken. Minimum follow-up was 15 months (range 15–167 months). Nineteen patients were hemipelvic resections (12 Type I+II and seven Type I+II+III, 11 of these cases included partial sacral resection) reconstructed by hemipelvic allograft and THA. In comparison, five patients had Type II acetabular resections, reconstructed with structural allograft, roof ring and THA. Functional outcome was assessed by the Toronto Extremity Salvage score (TESS) and the Musculoskeletal Tumor Society scores (MSTS87 and MSTS93). Results: Osteosarcoma and chondrosarcoma were the most frequent tumors. All patients required walking aids. In the hemipelvic group there were two early deaths (peri-operative haemorrhage and aplastic anaemia). In seven patients (37%), the allograft remained intact without infection but three required revision THA for component loosening. For these seven patients, the functional outcome scores were TESS 64%, MSTS87 17/35 and MSTS93 45% (mean follow-up 52 months). There were nine cases of deep infection (47%) with three patients maintaining a functional implant with antibiotic suppression. Of the remaining six patients with infection, four patients required hindquarter amputation, one patient required allograft removal and the allograft fragmented in the remaining patient. The 19th patient was revised following allograft fracture. Five patients sustained at least one allograft fracture. In the Type II acetabular group, three patients had no complications, and two patients sustained dislocations. The average scores were TESS 78%, MSTS87 21/35 and MSTS93 64% (mean follow-up 55 months). Conclusion: Reconstruction of large pelvic defects including the acetabulum using hemipelvic allograft and THA is associated with high complication rates, however when successful provides reasonable function. In comparison, the functional outcome after allograft and THA reconstruction of isolated Type II acetabular resections was better and more predictable

Introduction and Aims: Improved survival has motivated aggressive surgery with musculoskeletal tumors. Pelvic resection is challenging because of the constraints of adjacent vital anatomy, and the considerable impact on limb and visceral function. The aims of this study was to assess the functional, oncologic and surgical outcomes following resections of the bony pelvis. Method: Between 1996 and 2003, 49 patients underwent tumor resections of the pelvic ring. The mean age was 43 (range 15–72) years. There were 44 primary (36 bone, nine soft tissue) and five secondary tumors. Of the bone tumors, there were six osteosarcomas, five Ewings sarcomas, 12 chondrosarcomas and 13 others. Of the soft tissue tumors, nine were of neural origin. Tumor locations included the ilium, periacetabulum, pubic bones, sacrum or combinations of these. Neoadjuvant chemotherapy (seven patients) and pre-operative radiotherapy (eight patients) were also used. Function was assessed using the American Musculoskeletal Tumor Society Functional scoring system. No patient had metastases at presentation. Results: Surgery – There were 40 limb sparing resections and nine hindquarter amputations. The surgical margins were intralesional (four), marginal (12), wide (28) and radical (five). Of the limb sparing surgery, prosthetic reconstructions were used in nine patients, biologic reconstructions in seven patients a combination of biologic and prosthetic reconstructions in three cases and no reconstructions in the others. The mean operating time was five (range 1.5–10) hours. The mean intra-operative blood loss was 10 (range 2–26) units. The average length of stay was 22 (range 2–110) days. Fifty percent of patients developed acute complications. Survival – There was one intra-operative death. There were nine local recurrences and 16 metastases. Death from disease occurred at a mean time of 13 (range 1–51) months. Mean follow-up was 28 (range 1–90) months. Functional assessment – Hind quarter amputation and periacetabular resections had the worse functional outcome. These accounted for almost 40% of all cases. Surprisingly, patients with periacetabular resections had the best score for emotional acceptance. Conclusion: Pelvic resections are complex, demanding and accompanied by a high complication rate. Surgery significantly affects functional outcome. Disease control is similar to limb tumors and medium to long-term survival is possible. Emotional acceptance of surgery in survivors was surprisingly high. Major pelvic resection for malignancy appears justifiable

Introduction: Treatment of osteonecrosis continues to be a challenging problem in orthopedic practice. Arthroplasty is generally successful but long-term results are inferior especially in young adults. Alternative treatments such as core decompression and trap-door procedures provide only temporary benefits and need much improvement. The replacement of necrotic bone to promote osteogenesis and angiogenesis and healing subchondral bone are future approaches. Autogenous cancellous bone is the preferred graft material but its supply is limited. Allografts are useful but not as desirable as autografts. Substitutes for bone grafts have been actively researched but few are available currently. In this study, we have attempted to use genetically engineered bone marrow stem cells in order to enhance the healing of a bone defect in a mouse model. Materials and Methods: A bone marrow stem cell was cloned from Balb/c mice and transfected with LacZ and neomycin resistance genes. The cells were cultured for 7 to 10 days and both the osteoblastic and angiogenic properties of the cells were examined using Northern blots to detect osteocalcin and VEGF gene expression. The cells were also analyzed for alkaline phosphatase activity to demonstrate the osteoblastic phenotype of the cells. A suspension containing 2 x 10. 7. cells/ml phosphate buffered solution was prepared for cell transplantation. A total of forty-eight, 8-week old Balb/c mice were used in this study. A 1.2 mm defect was created bilaterally with an electric drill in the femurs of 24 mice to mimic the core decompression and trap-door procedures. 2 x 10. 6. cells were transplanted into each defect of the right femur while the left femur served as a control trap-door defect which was injected with PBS but without cells. An equal number of cells were injected either at subcutaneous sites, in the hindquarter muscles, or into the renal capsule (8 mice in each site) to evaluate ossification at ectopic sites. Animals were sacrificed at 2, 4, 6 and 8 weeks. Defect repair was evaluated radiographically and the contribution to osteogenesis by transplanted cells was studied histomorphometrically using tissue sections stained with X-gal as well as biochemically on DNA extracts using primers for the neomycin resistance gene. Results: Radiopaque tissue appeared two weeks after the cells were transplanted into bone defects, muscle, subcutaneous sites, and the renal capsule. Histological analysis demonstrated that these tissues consist of newly formed bone from transplanted cells that stained positively with X-gal and contained neo DNA. The repair tissue did not contain cartilaginous areas indicating that ossification surrounding the D1-BAG cells was not through the endochondral process. At four weeks, 4 of 6 femora showed a defect that was filled with new bone. At 6 weeks, all of the defects (6 of 6) contained fully restored bone. However, in the control side that was injected with PBS (no cells) only 2 of 6 at 4 weeks, 3 of 6 at 6 weeks, and 5 of 6 at 8 weeks showed complete repair. All histological sections of bone defects (n = 24) were examined histomorphometrically using a computerized image analysis system. Transplantation of marrow stem cells into bone defects produced more bone at an earlier time point than controls and, the process of enhanced ossification continued throughout the healing process. Discussion: The cloned bone marrow stem cell can directly form bone after transplantation into bone defects and into ectopic sites, indicating that the in vitro expanded bone marrow stem cells can serve as a grafting material to enhance healing of bone defects and the treatment of osteonecrosis. In addition, this study demonstrates that genetic labelling is a useful tool in studies of cell differentiation in vivo and that bone marrow stem cells may be useful as a carrier of genetically-engineered factors in the treatment of skeletal diseases