Abstract

The management of primary malignant bone tumors with metastatic disease at presentation remains a challenge. While surgical resection has been shown to improve overall survival among patients with non-metastatic malignant bone tumors, current evidence regarding the utility of surgery in improving overall survival in metastatic patients remains limited.

The 2004–2016 National Cancer Database (NCDB) was queried using International Classification of Diseases 3rd Edition (ICD-O-3) topographical codes to identify patients with primary malignant bone tumors of the extremities (C40.0-C40.3, C40.8 and C40.9) and/or pelvis (C41.4). Patients with malignant bone tumors of the axial skeleton (head/skull, trunk and spinal column) were excluded, as these cases are not routinely encountered and/or managed by orthopaedic oncologists. Histological codes were used to categorize the tumors into the following groups - osteosarcomas, chondrosarcomas, and Ewing sarcomas. Patients who were classified as stage I, II or III, based on American Joint Commission of Cancer (AJCC) guidelines, were excluded. Only patients with metastatic disease at presentation were included in the final study sample. The study sample was divided into two distinct groups – those who underwent surgical resection of the primary tumors vs. those who did not receive any surgery of the primary tumor. Kaplan-Meier survival analysis was used to report unadjusted 5-year overall survival rates between patients who underwent surgical resection of the primary tumor, compared to those who did not. Multi-variate Cox regression analyses were used to assess whether undergoing surgical resection of the primary tumor was associated with improved overall survival, after controlling for differences in baseline demographics, tumor characteristics (grade, location, histological type and tumor size), and treatment patterns (underwent metastatectomy of distal and/or regional sites, positive vs. negative surgical margins, use of radiation therapy and/or chemotherapy). Additional sensitivity analyses, stratified by histologic type for osteosarcomas, chondrosarcomas and Ewing sarcomas, were used to assess prognostic factors for overall survival.

A total of 2,288 primary malignant bone tumors (1,121 osteosarcomas, 345 chondrosarcomas, and 822 Ewing sarcomas) with metastatic disease at presentation were included – out of which 1,066 (46.0%) underwent a surgical resection of the primary site. Overall 5-year survival rates, on unadjusted Kaplan-Meier log-rank analysis, were significantly better for individuals who underwent surgical resection vs. those who did not receive any surgery (31.7% vs. 17.3%; p<0.001). After controlling for differences in baseline demographics, tumor characteristics and treatment patterns, undergoing surgical resection of primary site was associated with a reduced overall mortality (HR 0.42 [95% CI 0.36–0.49]; p<0.001). Undergoing metastectomy (HR 0.92 [95% CI 0.81–1.05]; p=0.235) was not associated with a significant improvement in overall survival. On stratified analysis, radiation therapy was associated with improved overall survival for Ewing Sarcoma (HR 0.71 [95% CI 0.57–0.88]; p=0.002), but not for osteosarcoma (HR 1.14 [95% CI 0.91–1.43]; p=0.643) or chondrosarcoma (HR 1.08 [95 % CI 0.78–1.50]; p=0.643). Chemotherapy was associated with improved overall survival for osteosarcoma (HR 0.50 [95% CI 0.39–0.64]; p<0.001) and chondrosarcoma (HR 0.62 [95% CI 0.45–0.85]; p=0.003), but not Ewing sarcoma (HR 0.79 [95% CI 0.46–1.35]; p=0.385).

Surgical resection of the primary site significantly improves overall survival for primary malignant bone tumors with metastatic disease at presentation. Physicians should strongly consider surgical resection of the primary tumor, with adjunct systemic and/or radiation therapy (dependent on tumor histology), in patients presenting with metastatic disease at presentation.

Aims

Despite few good-quality studies on the subject, total hip arthroplasty (THA) is increasingly being performed for displaced intracapsular fractures of the neck of femur. We compared outcomes of all patients with displacement of these fractures treated surgically over a ten-year period in one institution.

Introduction

The number of revision hip arthroplasty procedures is rising annually with 7852 such operations performed in the UK in 2010. These are expensive procedures due to pre-operative investigation, surgical implants and instrumentation, protracted hospital stay, and pharmacological costs. There is a paucity of robust literature on the costs associated with the common indications for this surgery.

Introduction

Foot and ankle is a well-established and growing sub specialty in orthopaedics. It accounts for 20 to 25 per cent of an average department's workload. There are two well established foot and ankle specialist journals but for many surgeons the Journal of Bone and Surgery (JBJS) remains the preeminent journal in orthopaedics and a highly sought after target journal for publication of research. It is our belief that foot and ankle surgery is underrepresented in the JBJS. We undertook a study to test this hypothesis.

Akins original description of his osteotomy did not describe the use of any metal work. Today the osteotomy is most commonly held and fixed with either a staple or screw. We describe the results obtained with a simple suture technique. Methods Data was collected prospectively on 125 patients undergoing an Akin osteotomy. Hallux valgus (HV) and intermetatarsal (IM) angles pre and postoperatively were recorded. Patients were reviewed at 6 week follow up. Cost analysis was also performed comparing different fixation types.

111 of the patients were female and 14 male. The average age at time of surgery was 49 years. 104 cases were in conjunction with hallux valgus correction while 21 cases were for hallux interphalangeus. The mean preoperative HV angle was 33.3 degrees (range 22 to 53), and the IM angle 13.3 degrees (range 9 to 25). At the 6 week follow up all patients had shown signs of radiological union. The postoperative HV angle was 12.4 degrees (range 7 to 17) and the IM angle 6.4 degrees (range 5 to 11). All patients maintained their correction. There were no complications, infections or fixation problems. All patients were satisfied with their surgery and would have it repeated again. The suture technique was the most cost effective method.

We describe a quick, easy, implant free method of fixing the Akin osteotomy. There is no need for metalwork removal and in today's world of austerity and the current climate of widespread budget constraints we describe a cost effective method which is clinically just as effective as methods requiring a staple or screw.

Aim

To demonstrate the effect of location of the split of the plaster on the raised intercompartmental pressure in the volar and dorsal compartments.

Introduction

The Two Week Waiting Time Standard, which requires that patients with suspected cancer referred by general practitioners should be seen within 2 weeks, was introduced in 2000. We reviewed the performance of this standard with regards to proportion of patients seen and tumour detection rates.

Introduction: Bone marrow derived mesenchymal stem cells are a potential source of cells for the repair of articular cartilage defects. Hypoxia has been shown to improve chondrogenesis in adult stem cells. In this study we characterised bone marrow derived stem cells and investigated the effects of hypoxia on gene expression changes and chondrogenesis.

Material and Methods: Adherent colony forming cells were isolated and cultured from the stromal component of bone marrow. The cells at passage 2 were characterised for stem cell surface epitopes, and then cultured as cell aggregates in chondrogenic medium under normoxic (20% oxygen) or hypoxic (5% oxygen) conditions for 14 days. Gene expression analysis, glycosoaminoglycan and DNA assays, and immunohistochemical staining were determined to assess chondrogenesis.

Results: Bone marrow derived adherent colony forming cells stained strongly for markers of adult mesenchymal stem cells including CD44, CD90 and CD105, and they were negative for the haematopoietic cell marker CD34 and for the neural and myogenic cell marker CD56. Interestingly, a high number of cells were also positive for the pericyte marker 3G5. Cell aggregates showed a chondrogenic response and in lowered oxygen there was increased matrix accumulation of proteoglycan, but less cell proliferation, which resulted in 3.2-fold more glycosoaminoglycan per DNA after 14 days of culture. In hypoxia there was increased expression of key transcription factor SOX6, and the expression of collagens II and XI, and aggrecan was also increased.

Discussion: Pericytes are a candidate stem cell in many tissue and our results show that bone marrow derived mesenchymal stem cells express the pericyte marker 3G5. The response to chondrogenic culture in these cells was enhanced by lowered oxygen tension, which up-regulated SOX6 and increased the synthesis and assembly of matrix during chondrogenesis. This has important implications for tissue engineering applications of bone marrow derived stem cells.

Introduction: There is an ever-increasing clinical need for the regeneration and replacement of tissue to replace soft tissue lost due to trauma, disease and cosmetic surgery. A potential alternative to the current treatment modalities is the use of tissue engineering applications using mesenchymal stem cells that have been identified in many tissues including the fat pad. In this study, stem cells isolated from the fat pad were characterised and their differentiation potential assessed.

Materials and Methods: The infrapatellar fat pad was obtained from total knee replacement for osteoarthritis. Cells were isolated, expanded and stained for a number of stem cell markers. For adipogenic differentiation, cells were cultured in adipogenic inducing medium (10ug/ml insulin, 1uM dexamthasone, 100uM indomethacin and 500uM 3-isobutyl-1-methyl xanthine). Gene expression analyses and Oil red O staining was performed to assess adipogenesis.

Results: Cells at passage 2 stained strongly for CD13, CD29, CD44, CD90 and CD105 (mesenchymal stem cell markers). The cells stained sparsely for 3G5 (peri-cyte marker). On gene expression analyses, the cells cultured under adipogenic conditions had almost a 1,000 fold increase in expression of peroxisome proliferator-activated receptor gamma-2 (PPAR gamma-2) and 1,000,000 fold increase in expression of lipoprotein lipase (LPL). Oil red O staining revealed triglyceride accumulation within typical adipogenic morphology, confirming the adipogenic nature of the observed vacuoles, and showed failure of staining in control cells.

Discussion: Fat pad derived stem cells expressed a cell surface epitope profile of mesenchymal stem cells, and exhibited the potential to undergo adipogenic differentiation. Our results show that the human fat pad is a viable potential autogeneic source for mesenchymal stem cells capable of adipogenic differentiation as well as previously documented ostegenic and chondrogenic differentiation. This cell source has potential use in tissue engineering applications.

It is debatable whether high flexion total knee arthroplasty (TKA) designs will improve postoperative flexion, function or will diminish the need for manipulation under anesthesia (MUA). We retrospectively analyzed range of motion (ROM), flexion, Knee Society Score (KSS), and rate of MUA in a consecutive group of patients who underwent TKA with a conventional PS or a high flexion (HF) insert using identical surgical technique, implant design and postoperative care. Fifty TKAs with a standard posterior stabilized insert (PS) were matched with 50 who received a high flexion insert (HF) for patient’s age, gender, preoperative ROM, and KSS. The patient’s ROM and KSS were obtained at 6 weeks, 4 months, and 1 year postoperatively. The outcome variables (flexion, ROM, KSS and manipulation rate) in the two groups were compared using the generalized estimating equations method. A second analysis of patients with preoperative flexion equal or greater than 120 degrees was performed. The ROM, flexion, and patient reported KSS was similar in the PS and HF groups at each one of the time periods. The rate of MUA was also similar. Patients with a preoperative ROM of at least 120° showed similar results. Our study found that 1 year after surgery, patients who underwent TKA with a PS or a HF insert achieved similar flexion, ROM and function.

Juvenile idiopathic arthritis (JIA) affecting the hip can cause debilitating pain and walking disability in children. Total hip replacement offers the potential of a pain free joint and a significant improvement in function. There remains the concern regarding the high rates of aseptic loosening of cemented total hip replacements in this group of patients, and there is evidence that younger patients have higher failure rates.

The aim of this study was to look at the results of uncemented total hip replacement in children with Juvenile Idiopathic Arthritis and in particular to assess any problems associated with performing this surgery in the presence of open growth plates in the acetabular and trochanteric regions.

Between 1995 and 2005, 56 uncemented total hip replacements were carried out in 37 children with JIA with a mean follow up of 7.5 years (range 3 to 12.5). 25 of the hips had ceramic on ceramic bearings. The mean age at surgery was 13.9 years (range 11–16). 19 patients underwent bilateral procedures. All patients showed a significant improvement in their HSS Hip scores (p< 0.01). Two CAD CAM femoral stems were revised for gross subsidence and three acetabular components were revised for loosening. Four polyethylene liners were exchanged due to wear. 51 of 53 (96%) femoral stems and 50 (94%) acetabular components remain well fixed at latest follow up with no signs of loosening. There were no dislocations or infections.

Uncemented fixation appears to work well in this challenging group of patients even in the presence of open growth plates. Implant choice is important to avoid problems of subsidence and loosening. Ceramic bearings available for small implant sizes give promise of improved performance compared to polyethylene over the long term.

Introduction: There have been several recent studies outlining the role of femoroacetabular impingement (FAI) as a cause of early osteoarthritis in the non-dysplastic hip. The lesions can either be on the femoral side “cam” or acetabular “pincer”. The aim of surgical treatment of FAI is to improve the femoral head neck offset thereby improving joint clearance and preventing abutment of the femoral neck against the acetabulum. The classic treatment for FAI pioneered by Ganz involves dislocation of the femoral head through a trochanteric flip osteotomy. The procedure is extensive, technically difficult and not without complications.

Hip arthroscopic debridement of FAI lesions offers similar results to open procedures allowing for full inspection of the joint and the treatment of any chondral lesion but with a quicker recovery time. It nonetheless has a very long learning curve and even in the most experienced hands the treatment of impingement lesions is complicated and technically challenging.

The purpose of this cadaveric study was to assess the degree of exposure obtained using two different limited anterior approaches to the hip which would allow effective surgical treatment of cam and pincer FAI.

Methods: We investigated two mini anterior approaches to the hip joint based on the Heuter and direct anterior approach to compare the parts of the acetabulum and femoral head exposed for the treatment of FAI in a total of 20 hips in 10 (5 male, 5 female) cadaveric specimens. Neurovascular structures were recorded in relation to the two approaches. The area of femoral head and acetabular rim exposed via each approach was documented and quantified.

Results: We found that the two approaches were easy and reproducible. Both allowed exposure to the anterolateral aspect of the femoral head. The mean length of acetabular rim accessible via the Heuter approach was 1.9cm (1.1–2.4) and 2.2cm (1.2–3) using the direct anterior approach The area of acetabular rim accessible varied according to the approach (p< 0.001). We also found that the position of the anterior inferior iliac spine in relation to the acetabular rim also affected the area of acetabular rim exposed (p< 0.001). The most proximal nerve branch to sartorious was found 7.3cm (6.5–8.7cm) distal to the anterior inferior iliac spine. The most proximal nerve branch to rectus femoris was located 8.6cm (7–10) distal to the anterior inferior iliac spine and was consistently found to be distal to the nerve to sartorious.

Discussion: Treating impingement of the hip through a direct open approach is not a novel idea. A recent report of failed arthroscopic labral debridement, describes treatment of the underlying bony impingement in some cases by a combination of hip arthroscopy followed by anterior arthrotomy.

In summary cam and pincer impingement of the hip can be treated by either the direct anterior or Heuter approach. The choice of approach would be dictated after careful consideration as to which portion of the anterior acetabular rim required surgery, with more lateral acetabular lesions being favoured by the Heuter approach and more medial impingement sites by the anterior approach we have described.

To investigate whether stopping clopidogrel on admission and subsequently delaying surgery in patients with hip fracture increases the risk of cerebrovascular complications and in-hospital mortality.

Retrospectively studied patients with hip fractures on clopidogrel admitted to our trauma unit between January 1, 2006 and May 31, 2007. Fifteen patients aged over 65 years with intra-capsular and extra-capsular hip fracture were reviewed. Demographic details of patients were recorded including the primary diagnosis on admission, timing of surgical intervention performed, pre-and post-operative haemoglobin and classification according to the American Society of Anesthesiologists (ASA) and in hospital mortality.

Eight fractures were intra-capsular and seven extra-capsular. The mean preoperative haemoglobin levels were 12.4 (range 9.9 to 14.1), the mean postoperative haemoglobin level were 9.7 (range 8 to 12.3). Four patients required blood transfusions, 8 unit of blood were transfused in total postoperatively. The mean delay in surgery were 9.1 days (range 7 to 14 days). The mean duration of hospital stay was 21 days (range, 8 to 45 days). The 30-day mortalities were 3/15 (20%). Mortalities were secondary to cerebrovascular events.

In summary, we found increase mortality and requirement for blood transfusion in patients on clopidogrel in whom surgery were delayed. A well designed research is needed to achieve evidence based management, but this may require several years due to the small, but increasing, number patients seen at present. We suggest early surgery for elderly hip fracture patients on clopidogrel. Patients on clopidogrel should be cross matched pre-operatively for red blood cells and platelets and experienced surgeon should perform the procedure.

Introduction: Navigation increases the precision and reproducibility of reconstruction in THR. It is important for the surgeon to be able to trust the reproducibility of the navigator and that navigated surgery should produce better results than those obtained by the surgeon by himself. The aim of this study is to determine the reproducibility and trustworthiness of a navigation system for acetabular reconstruction and to compare the precision of the navigator with that of the surgeon.

Materials and methods: A total of 101 THRs were carried out in 99 patients using image-free navigation. The precision and reproducibility of the navigator were measured with 30 postoperative CT scans. The blind estimates of the surgeons for inclination and anteversion were compared to the values of the navigator; the navigator was as accurate as the surgeon in 101 cases.

Results: The precision of the navigator for inclination was 4.4° with a reproducibility of 0.03 and for ante-version it was 4.1° with a reproducibility of 0.73. The precision of experienced surgeons for inclination was 11.5° and 12.3° for anteversion (less experienced surgeons had a precision for inclination of 13.1° and for anteversion of 13.9°).

Conclusions: Computer accuracy for the real value of a CT scan is always within 5°. The estimations of the surgeons with mechanical guides, experience and good judgment are about 12 degrees that of the navigation system. However the percentage of values 5° higher than the desired levels in experienced surgeons is seen in about 30% of cases (in less experienced surgeons, in about 50%). The computer can eliminate acetabular malposition to within about 5 degrees for desired values and in this way improve stability and wear.

Objective: To identify institution specific risk factors for developing MRSA surgical site infection (SSI) and develop an objective mechanism to estimate the probability of MRSA infection in a given patient admitted to the orthopaedic unit.

Design: A cohort study was performed to identify risk factors in all patients who had MRSA infection during admission on the orthopaedic unit between January 2002 and December 2004. Logistic regression was used to model the likelihood of MRSA. A stepwise approach was employed to derive a model. The MRSA prediction tool was developed from the final model.

Results: Of the 11 characteristics included in the logistic regression, the features that strongly predicted a MRSA infection were ASA grade, patient’s residence and reason for admission.

110 had MRSA infection in their surgical wound. 83 of 110 (75.5%) patients were non-elective admissions, of which 49 (60%) were proximal femur fractures. 20% of proximal femur fractures admitted from nursing home and 7.8% from their own homes developed SSI with MRSA. This cohort of SSI with MRSA had an average of 5.7(1–18) previous admissions. 25 (23%) had been previously colonised with MRSA. Majority of them (76%) were between 70–90 years old and were ASA grade 3–4.

Conclusion: Through multivariate modelling technique we were able to identify the most important determinants of patients developing SSI with MRSA in our institute and develop a tool to predict the probability of MRSA in a given patient. This knowledge can be used to guide the use of appropriate prophylactic antibiotic and to take other required measures to avoid the SSI with MRSA.

Introduction: The Two Week Waiting Time (2wwt) Standard, which requires that patients with suspected cancer referred by general practitioners should be seen within 2 weeks, was introduced in 2000. We reviewed the performance of this standard with regards to proportion of patients seen and tumour detection rates.

Methods and Results: We reviewed all the referrals sent as “two week waiters” from January 2004 to December 2005, to our bone and soft tissue sarcoma service. These referrals were evaluated for

Whether or not the referral met established referral guidelines for bone and soft tissue tumours

This was compared with the total number of referrals to the unit and their tumour detection rates.

A total of 40 patients were referred as “two week waiters” in the given time period. They were seen on an average of 8 days following the referral. Of the 40 patients, four patients had soft tissue metastasis from a primary tumour elsewhere, and six had primary malignant soft tissue tumours. 12 had a benign bone/ soft tissue tumour. 18 (45%) patients had a non neoplastic pathology (6 Muscle tear/ herniation; 4 ganglion/bursa; 2 lumps that disappeared)

During the same period a total of 515 patients were referred by other routes.

Conclusion: Only 10 of 40 patients referred under the 2-week rule had malignant tumours. The majority of referrals to our service do not fall under this rule. Significant numbers of referral under the 2wwt standard are not in line with the referral guidelines. It is our impression that the 2-week rule, whilst highlighting the need of these patients to be seen urgently may distort clinical priorities and disadvantage patients referred from other sources.

Introduction: Brown tumours occur as a complication in patients with renal failure, due to secondary hyperparathyrodism. In these patients brown tumours commonly regress if the primary cause is treated. We present a rare case of recalcitrant brown tumour with unusual presentation and symptom complex requiring surgical intervention.

Case Report: 14-year-old girl with blindness presented with pain in the proximal tibia. Radiographs revealed a lytic lesion in the proximal tibia. Biopsy of the lesion showed osteoclast rich stroma. Blood investigations indicated renal impairment, and secondary hyperparathyroidism. She underwent repeated dialysis treatment, and her renal parameters and parathormone levels were brought back to within normal limits. However, there was no evidence of regression of the lesion. Hence, intralesional curettage of the brown tumour was performed while still maintaining her on regular dialysis. This resulted in complete healing of the brown tumour with no recurrence at latest follow-up. She recently had a renal transplant as a definitive treatment for her renal failure.

Conclusion: The patient in our case has got renal retinal dysplasia which resulted in juvenile renal failure and retinal pigmentary degeneration. The renal failure resulted in secondary hyperparathyroidism leading to the formation of bone tumour in the proximal tibia. Eventhough temporarily the renal parameters were restored to within normal limits, this tumour did not regress in size, and hence required surgical intervention. This case highlights the importance of detailed thorough investigations to find the primary cause and syndrome associated with juvenile renal failure which presented with only a bony abnormality.

Background: Giant-cell tumour (GCT) of bone is a benign but aggressive tumour, usually treated by radical surgical curettage. Surgical treatment of GCT involving the ischium is associated with a high local recurrence rate. We describe a case in which serial arterial embolisation and bisphosphonate treatment resulted in radiological healing of the tumour. So far we have avoided surgical treatment.

Case Report: A 40-year-old lady was referred to the bone tumour unit following a fall. A plain radiograph of the pelvis revealed a lytic lesion in the ischium, extending into the posterior column of the acetabulum and associated with a pathological fracture. Biopsy confirmed a diagnosis of GCT. Given the anatomic location, the tumour was treated with serial arterial embolisation and intravenous zoledronate infusions. Follow up at one-year shows healing of the lesion, with no radiological evidence of recurrence. The patient has so far avoided surgery.

Discussion: Serial arterial embolisation has been described in the treatment of giant cell tumours in anatomical regions where surgery is likely to be associated with significant morbidity, such as the sacrum. There is a sound theoretical basis for the use of bisphosphonates in this disease; they have been shown to cause apoptosis of the osteoclast-like giant cells and interfere with osteoclast recruitment. As far as we are aware this is the first case described in which embolisation and bisphosphonate treatment appears to have led to healing and stabilisation of the lesion. The durability of this response remains uncertain.

Aim: A study to compare bone remodeling (BMD changes) around the femoral component of a cemented and uncemented THR using DXA scan and Finite element analysis and to check the predictive value of remodelling simulations as a pre-clinical implant testing tool.

Methods: Twenty patients were recruited, ten for each implant type (Exeter and ABG-II). All volunteers underwent unilateral hip replacement. No patient had any metabolic bone disease or were on medication that would alter BMD. Each patient had a preopera-tive CT scan of the hip, in order to provide 3D bone shape and density data needed to construct a computer model. Each patient’s changes of BMD over a period of 12 months postoperatively were evaluated in a series of 4 follow-up DXA scans taken at 3 weeks, 3, 6 and 12 months post-op. For the computer simulation, Finite Element (FE) models of the affected femur were constructed for each patient and BMD changes predicted using strain adaptive bone remodelling theory. These patients were clinical followed up to access the hip scores (Merle d’Aubigne Postel)

Results: All the patients were Charnely group A and had excellent postoperative hip scores (average pain 5.5, walking 5.4 and range of motion 5.3) The Exeter stem DXA results show bone resorption in Gruen zone 3 (2.8% on average) and 4 (3.3%) whereas there is a tendency for bone deposition at regions 1, 6 and 7 (2% on average). The ABG-II stem results show bone resorption developing at regions 7 and 4 (6% and 2% respectively) and some bone formation at region 6 (2%). The simulation results have a tendency to overestimate amounts of bone resorption (20% at region 7 for the ABG-II, 12% at region 3 for the Exeter).

Conclusion: A comparison of the remodelling around a cemented and a non-cemented hip implant show important differences in the emerging patterns of adaptation. To our knowledge, very few published studies provide information on bone remodelling around cemented stems, and compare the results to those of an uncemented stem. Additionally, the simulation results suggest that these formulations can reproduce realistic patterns of bone adaptation. This study aims at providing the means for comparison and subsequent improvement of the accuracy of the simulations and thus helps develop a hip prosthesis that would led to least bone resorption.