When performing limb salvage operations for malignant bone tumours in skeletally immature patients, it is desirable to reconstruct the limb with a prosthesis that can be lengthened without surgery at appropriate intervals to keep pace with growth of the contra-lateral side. We have developed a prosthesis that can be lengthened non-invasively. The lengthening is achieved on the principle of electromagnetic induction. The purpose of this study was to look at our early experience with the use of the Non Invasive Distal Femoral Expandable
The reconstruction of peri-acetabular defects after severe bone loss or pelvic resection for tumor is among the most challenging surgical intervention. The Lumic® prosthesis (Implantcast, Buxtehude, Germany) was first introduced in 2008 in an effort to reduce the mechanical complications encountered with the classic peri-acetabular reconstruction techniques and to improve functional outcomes. Few have evaluated the results associated with the use of this recent implant. A retrospective study from five Orthopedic Oncology Canadian centers was conducted. Every patient in whom a Lumic® endoprosthesis was used for reconstruction after peri-acetabular resection or severe bone loss with a minimal follow-up of three months was included. The charts were reviewed and data concerning patients’ demographics, peri-operative characteristics and post-operative complications was collected. Surgical and functional outcomes were also assessed. Sixteen patients, 11 males and five females, were included and were followed for 28 months [3 – 60]. Mean age was 55 [17–86], and mean BMI reached 28 [19.6 – 44]. Twelve patients (75%) had a Lumic® after a resection of a primary sarcoma, two following pelvic metastasis, one for a benign tumor and one after a comminuted acetabular fracture with bone loss. Twelve patients (75%) had their surgery performed in one stage whereas four had a planned two-stage procedure. Mean surgical time was 555 minutes [173-1230] and blood loss averaged 2100 mL [500-5000]. MSTS score mean was 60.3 preoperatively [37.1 – 97] and 54.3 postoperatively [17.1-88.6]. Five patients (31.3%) had a cemented Lumic® stem. All patients got the dual mobility bearing, and 10 patients (62.5%) had the largest acetabular cup implanted (60 mm). In seven of these 10 patients the silver coated implant was used to minimize risk of infection. Five patients (31.3%) underwent capsular reconstruction using a synthetic fabric aiming to reduce the dislocation risk. Five patients had per-operative complications (31.3%), four were minor and one was serious (comminuted iliac bone fracture requiring internal fixation). Four patients dislocated within a month post-operatively and one additional patient sustained a dislocation one year post-operatively. Eight patients (50%) had a post-operative surgical site infection. All four patients who had a two-stage surgery had an infection. Ten patients (62.5%) needed a reoperation (two for fabric insertion, five for wash-outs, and three for implant exchange/removal). One patient (6.3%) had a septic loosening three years after surgery. At the time of data collection, 13 patients (81.3%) were alive with nine free of disease. Silver coating was not found to reduce infection risk (p=0.2) and capsuloplasty did not prevent dislocation (p=1). These results are comparable to the sparse data published. Lumic® endoprosthesis is therefore shown to provide good functional outcomes and low rates of loosening on short to medium term follow-up. Infection and dislocation are common complications but we were unable to show benefits of capsuloplasty and of the use of silver coated implants. Larger series and longer follow-ups are needed.
The reconstruction of peri-acetabular defects after severe bone loss or pelvic resection for tumor is among the most challenging surgical intervention. The Lumic® prosthesis (Implantcast, Buxtehude, Germany) was first introduced in 2008 in an effort to reduce the mechanical complications encountered with the classic peri-acetabular reconstruction techniques and to improve functional outcomes. Few have evaluated the results associated with the use of this recent implant. A retrospective study from five Orthopedic Oncology Canadian centers was conducted. Every patient in whom a Lumic® endoprosthesis was used for reconstruction after peri-acetabular resection or severe bone loss with a minimal follow-up of three months was included. The charts were reviewed and data concerning patients’ demographics, peri-operative characteristics and post-operative complications was collected. Surgical and functional outcomes were also assessed. Sixteen patients, 11 males and five females, were included and were followed for 28 months [3 – 60]. Mean age was 55 [17-86], and mean BMI reached 28 [19.6 – 44]. Twelve patients (75%) had a Lumic® after a resection of a primary sarcoma, two following pelvic metastasis, one for a benign tumor and one after a comminuted acetabular fracture with bone loss. Twelve patients (75%) had their surgery performed in one stage whereas four had a planned two-stage procedure. Mean surgical time was 555 minutes [173-1230] and blood loss averaged 2100 mL [500-5000]. MSTS score mean was 60.3 preoperatively [37.1 – 97] and 54.3 postoperatively [17.1-88.6]. Five patients (31.3%) had a cemented Lumic® stem. All patients got the dual mobility bearing, and 10 patients (62.5%) had the largest acetabular cup implanted (60 mm). In seven of these 10 patients the silver coated implant was used to minimize risk of infection. Five patients (31.3%) underwent capsular reconstruction using a synthetic fabric aiming to reduce the dislocation risk. Five patients had per-operative complications (31.3%), four were minor and one was serious (comminuted iliac bone fracture requiring internal fixation). Four patients dislocated within a month post-operatively and one additional patient sustained a dislocation one year post-operatively. Eight patients (50%) had a post-operative surgical site infection. All four patients who had a two-stage surgery had an infection. Ten patients (62.5%) needed a reoperation (two for fabric insertion, five for wash-outs, and three for implant exchange/removal). One patient (6.3%) had a septic loosening three years after surgery. At the time of data collection, 13 patients (81.3%) were alive with nine free of disease. Silver coating was not found to reduce infection risk (p=0.2) and capsuloplasty did not prevent dislocation (p=1). These results are comparable to the sparse data published. Lumic® endoprosthesis is therefore shown to provide good functional outcomes and low rates of loosening on short to medium term follow-up. Infection and dislocation are common complications but we were unable to show benefits of capsuloplasty and of the use of silver coated implants. Larger series and longer follow-ups are needed.
Curative resection of proximal humerus tumours is now possible in this era of limb salvage with endoprosthetic replacement considered as the preferred reconstructive option. However, it has also been linked with mechanical and non-mechanical failures such as stem fracture and aseptic loosening. One of the challenges is to ensure that implants will endure the mechanical strain under physiological loading conditions, especially crucial in long surviving patients. The objective is to investigate the effect of varying prosthesis length on the bone and implant stresses in a reconstructed humerus-prosthesis assembly after tumour resection using finite element (FE) modelling. Computed tomography (CT) scans of 10 humeri were processed in Mimics 17 to create three-dimensional (3D) cortical and cancellous solid bone models. Endoprostheses of different lengths manufactured by Stryker were modelled using Solidworks 2020. The FE models were divided into four groups namely group A consisting of the intact humerus and groups B, C and D composed of humerus-prosthesis assemblies with a body length of 40, 100 and 120 mm respectively and were meshed using linear 4-noded tetrahedral elements in 3matic 13. The models were then imported into Abaqus CAE 6.14. Isotropic linear elastic behaviour with an elastic modulus of 13400, 2000 and 208 000 MPa were assigned to the cortical bone, cancellous bone and prosthesis respectively and a Poisson's ratio of 0.3 was assumed for each material. To represent the lifting of heavy objects and twisting motion, a tensile load of 200 N for axial loading and a 5 Nm torsional load for torsional loading was applied separately to the elbow joint surface with the glenohumeral joint fixed and with all contact interfaces defined as fully bonded. A comparative analysis against literature was performed to validate the intact model. Statistical analysis of the peak von Mises stress values collected from predicted stress contour plots was performed using a one-way repeated measure of analysis of variance (with a Bonferroni post hoc test) using SPSS Statistics 26. The average change in stress of the resected models from the intact state were then determined.Introduction and Objective
Methods
Debate surrounds the optimum operative treatment of periprosthetic distal femoral fractures (PDFFs) at the level of well fixed femoral components; lateral locking plate fixation (LLP-ORIF) or distal femoral replacement (DFR). To determine which attributed the least peri-operative morbidity and mortality we performed a retrospective cohort study of 60 consecutive unilateral PDFFs of Su types II (40/60) and III (20/60) in patients ≥60 years; 33 underwent LLP-ORIF and 27 underwent DFR. The primary outcome measure was reoperation. Secondary outcomes included perioperative complications and functional mobility status. Kaplan Meier survival analysis was performed. Cox multivariable regression analysis identified risk factors for reoperation after LLP-ORIF. Mean length of follow-up was 3.8 years (range 1.0–10.4). One-year mortality was 13% (8/60). Reoperation rate was significantly higher following LLP-ORIF: 7/33 vs 0/27, p=0.008. For the endpoint reoperation, five-year survival was better following DFR: 100% compared to 70.8% (51.8 to 89.8 95%CI) (p=0.006). For the endpoint mechanical failure (including radiographic loosening) there was no difference at 5 years: ORIF 74.5% (56.3 to 92.7); DFR 78.2% (52.3 to 100), p=0.182). Reoperation following LLP-ORIF was independently associated with medial comminution: HR 10.7 (1.45 to 79.5, p=0.020). Anatomic reduction was protective against reoperation: HR 0.11(0.013 to 0.96, p=0.046). When inadequately fixed fractures were excluded differences in survival were no longer significant: reoperation (p=0.156); mechanical failure (p=0.453). Reoperation rates are higher following LLP-ORIF of low PDFFs compared to DFR. Where adequate reduction, proximal fixation and augmentation of medial comminution is used there is no difference in survival between LLP-ORIF and DFR.
Computer Tomography (CT) imaging has been limited to beam hardening artefacts until now. Literature has failed to describe sensitivity and specifity for loosening of endoprothesis in CTs, as metal artefacts have always influenced the diagnostic value of CTs. In recent years a new technology has been developed, the Dual Energy CT. Dual Energy CT scanners simultaneously scan with two tubes at different energy levels, most commonly 100kVp and 140kVp. Furthermore pictures gained from Dual Energy CTs are post-processed with monoenergetic reconstruction, which increases picture quality while further reducing metal artefacts. This promising technology has increased the diagnostic value preventing more radiation for the patients, for example in detection of kidney stones or to map lung perfusion. In the musculoskeletal imaging it has not been established yet and further clinical investigations are necessary. Thus the aim of this study is to describe sensitivity and sensibility for endoprothesis loosening of this novel technology. 53 prospective patients (31 total hip- and 22 total knee-arthoplasties) who were planned for revision surgery underwent preoperative Dual Energy CT examination. All scans were performed with a second-generation, dual-energy multi-detector CT scanner. And all pictures were post-processed with monoenergetic reconstruction. Radiologists were blinded for patient´s history. Senior consultants, who are specialized in arthroplasty of the hip and the knee, performed surgery. Intraoperative information was used as gold standard.Introduction
Material and Methods
Four patients had obvious infection confirmed by histology and/or microbiology prior to surgery. Endoprosthetic Reconstruction was performed as a 1 stage procedure in 13 and as a 2 stage in 4. Complications occurred in 5 patients. These included recurrence of infection in 1, persistent pain in 1, aseptic loosening in 1, periprosthetic fracture in 1 and a non ST myocardial infarction in 1. At the last follow-up, (mean 5years, range 1–18years) majority of patients achieved good range of motion and good mobility.
The proximal tibia (PT) is the anatomical site most frequently affected by primary bone tumours after the distal femur. Reconstruction of the PT remains challenging because of the poor soft-tissue cover and the need to reconstruct the extensor mechanism. Reconstructive techniques include implantation of massive endoprosthesis (megaprosthesis), osteoarticular allografts (OAs), or allograft-prosthesis composites (APCs). This was a retrospective analysis of clinical data relating to patients who underwent proximal tibial arthroplasty in our regional bone tumour centre from 2010 to 2018.Aims
Methods
The risk of haematogenic periprosthetic joint infection (PJI) after dental procedures is discussed controversially. To our knowledge, no study has evaluated infections according to the origin of infection based on the natural habitat of the bacteria. We investigated the frequency of positive monomicrobial cultures involving bacteria from oral cavity in patients with suspected PJI compared to bone and joint infections without joint prosthesis. In this retrospective study we included all patients with suspected PJI or bone and joint infection without endoprosthesis, hospitalized at our orthopaedic clinic from January 2009 through March 2014. Excluded were patients with superficial surgical site infections or missing data. Demographic, clinical and microbiological data were collected using a standardized case report form. Groups were compared regarding infections caused by oral bacteria. χ2 test or Fisher's exact test was employed for categorical variables and t-test for continuous variables.Aim
Method
Sixty eight consecutive patients underwent proximal humeral replacement with a fixed fulcrum massive endoprosthesis, for tumour, between 1997 and 2007. The mean age was 46 years, (7–87). Ten patients were lost to follow up and 16 patients died. The 42 surviving patients were assessed using the Musculoskeletal Tumour Society (MSTS) Score and the Toronto Extremity Salvage Score (TESS). The mean MSTS score was 72.3% and the mean TESS was 77.2%. Four of 42 patients received a new constrained humeral liner to reduce the risk of dislocation. This sub group of 4 patients had a mean MSTS score of 77.7% and a mean TESS of 80.0%. Endoprosthetic replacement for tumour of the proximal humerus using this prosthesis is a reliable operation yielding good functional results without the documented problems of unconstrained prostheses. The performance of this prosthesis is expected to improve further with the new constrained humeral liner.
Sixty eight consecutive patients underwent proximal humeral replacement with a fixed fulcrum massive endoprosthesis for tumour between 1997 and 2007. The mean age was 46 years (7-87). Ten patients were lost to follow up and 16 patients died. The 42 surviving patients were assessed using the Musculoskeletal Tumour Society (MSTS) Score and the Toronto Extremity Salvage Score (TESS). The mean MSTS score was 72.3 % and the mean TESS was 77.2 %. Four of 42 patients received a new constrained humeral liner to reduce the risk of dislocation. This sub group of 4 patients had a mean MSTS score of 77.7 % and a mean TESS of 80.0%. Endoprosthetic replacement for tumour of the proximal humerus using this prosthesis is a reliable operation yielding good functional results without the documented problems of unconstrained prostheses. The performance of this prosthesis is expected to improve further with the new constrained humeral liner.
Revision THA presents significant challenges for the surgeon when the proximal femur is deficient or mechanically unreliable. The aim of this study is to assess the clinical and functional results of the use of tumor enndoprosthesis to reconstruct the proximal femur when there is massive bone loss. A prospective study was conducted involving 10 cases. The follow up of the cases ranged from 12 months to 30 months with a mean period of an average of 23months. The indications for revision surgery were aseptic loosening in 9 cases and septic loosening in one case Harris hip score was used for pre and postoperative clinical evaluation of the patientsBackground
Patients and Methods
Endoprosthetic reconstruction is an established method of treatment for primary bone tumours in children. Traditionally these were implanted with cemented intramedullary fixation. Hydroxyapatite collars at the shoulder of the implant are now standard on all extremity endoprostheses, but older cases were implanted without collars. Uncemented intramedullary fixation with hydroxyapatite collars has also been used in an attempt to reduce the incidence of problems such as aseptic loosening. Currently there are various indications that dictate which method is used. To establish long term survivorship of cemented versus uncemented endoprosthesis in paediatric patients with primary bone tumours.Background
Aims
Complications included: Superficial infection (1), deep infection (1); Recurrence 2; Improper cementing (2); Neuropraxia [radial nerve] (8); Subluxation of prosthesis head (8); Post radiotherapy skin necrosis and contracture (1); 4 patients died.
Bipolar hip arthroplasty was introduced to alleviate the problems of hip pain, acetabular protrusion and femoral stem loosening associated with unipolar prosthesis. Earlier generation bipolar endoprosthesis used to cause varus fixation of outer head which led to the unacceptably high incidence of dislocation, component disassembly and fractures of the polyethylene bearing insert. Second generation endoprosthesis with a self centering mechanism were introduced to overcome these problems. This new design incorporates a polar offset by setting the center of rotation of the inner head proximal to the center of rotation of the outer head, which generates a valgus producing moment at the outer cup. There is a controversy whether this mechanism works in vivo, more so in indigenous prosthesis. A retrospective observational study was done on 37 subjects, which included 21 males and 16 females. The first radiograph was taken with the patient standing and bearing full weight over the endoprosthetic leg and abducting the contra lateral limb as much as possible. The second radiograph was taken with the patient standing neutral and bearing weight on both the legs. Abduction and adduction views were then taken in supine position. The radiographs were analyzed using the method similar to that of Drinker and Murray. The adductive motion from abduction to neutral position is within the range of inner bearing oscillation. Modified Harris Hip Score was used to evaluate the patients clinically. Results were analyzed using Wilcoxon Matched-Pairs Signed-Ranks Test, Students t-test and Karl Pearson correlation statistics. The mean outer head alignment changed from 42.46 degrees ±13.62 (range 10 to 72 degrees) to 31.93 degrees ± 10.59 (range 8 to 50 degrees) in moving from abduction to neutral position in weight bearing position. The analysis showed that 68.66% of the total motion occurred at the outer bearing in weight bearing position whereas 73.86% of the total motion occurred at the outer bearing in supine position. The difference between distribution of motion between supine and weight bearing position was not found to be statistically different using Wilcoxon Matched-Pairs Signed-Ranks Test (p = 0.3164) and unpaired students t test (p = 0.35). No correlation was found between weight of the patient and time of follow up with outer head alignment and differential distribution of motion. Self centering mechanism of bipolar endoprosthesis works in vivo under physiological loads and aligns the cup in neutral or valgus position till an average follow up of 10 months. Though the motion occurs at both the bearing surfaces outer bearing motion clearly predominated in both weight bearing as well as supine position.
With a new mechanical navigation system for the cup with a special cup probe and guiding system the best position is found intraoperatively according to ROM, impingement, luxation and tension of the muscles.
The higher resisting torque against dislocation and the large range of motion due to the enlarged effective head diameter substantiate the use of eccentric dual-mobility cups in case of total hip joint instability [1,2]. As a result of force-dependent self-centering mechanism, an increased movement of the intermediate-component can be expected whose effect on wear propagation is unknown so far. Currently available hip joint simulators are only able to vary the load by the absolute value and not by the direction of resulting force. Therefore, the uniaxial force transmission may lead to a unique and stable alignment of the intermediate-component during testing. The purpose of this numerical study was to evaluate relative movements of the intermediate-component during daily life activities with respect to wear propagation. The numerical analysis was based on a standard dual-mobility system consisting of a polished metallic cup, a UHMWPE intermediate-component (40 mm outer diameter) with an eccentric offset of 2 mm and a 28 mm ceramic femoral head [Fig. 1]. The relative motion of the intermediate-component was affected by the geometrically generated self-centering torque (TC) and the friction torque for inner (TFi) and outer (TFo) articulation around the centre of rotation Z1[Fig. 2]. In order to consider lubrication conditions the lambda ratio was estimated for different daily life activities [3], including the calculation of composite roughness and minimum film thickness for a ball-on-plate configuration. The friction torque was related to the product of load (Introduction:
Method:
The aim of this study was to analyze the frequency and reveal the most common reasons of the endoprosthetic instability in patients with malignant bone tumors. From 1992 – 2008, 625/515 patients, endoprosthetic replacement of major joints were performed. The median age of the patients was 30.3 years (13 to 72 years). Aseptic instability was observed after 3/71(4.2%) humeral joint replacement out of total operations at this location, after 4/80 (5%) hip prosthesis, after 19/133 (14%) proximal tibial prostheses, after 44/299 (14.7%) distal femoral prostheses and after 2/37 (5.4%) total femur replacements. The retrospective analyses has shown that the reasons of instability were the following: aseptic loosening of the stems of endoprosthesis in 26 cases (24.4%), stem break in 31 (36.1%), endoprosthetic unit destruction in 10 (11.6%), untwistment of fixational screws in 10 (11,6%), migration of hip endoprosthesis components in 2 (2.3%) and endoprosthesis dislocation in 12 (14%). The timing of endoprosthetic instability ranged from 7 days to 12.2 years (average 26.2 months). Statistic analyses was performed in a group of patients with aseptic endoprosthesis instability developed after proximal tibia and distal femur resection. We conclude that the most frequent reason of aseptic instability was endoprosthetic stem break. The instability rate was actually lower among the patients who had underwent 5–10cm distal tibia resection comparing with the group of 10–15cm bone mass resection (p=0.05). Femoral resection enhanced the instability frequency comparing with proximal tibia resection in the group of 5–10cm bone mass resection (p=0.05).
The aim of this study was to analyze complications and functional outcomes after individual and module endoprosthesis. From 1993 to 2008 in our clinic 42 patients with bone sarcomas were treated with resection and endoprosthetic reconstruction of large joints. In 29 patients we have applied individual, in 13 patients module prosthesis. We have assessed complications and functional results. For individual prosthesis: pyoseptic complications-4 (9,52%) pts, orthopedic events-9 (21,43%) pts, local recurrences-5 (11,90%); functional results: “excellent”-10,34% (3/29), “good”-48,28% (14/29), “satisfactory”-24,14% (7/29), “non-satisfactory”-17,24% (5/29). For module prosthesis: Only in one patient local recurrence has been observed. Functional results are so: “excellent”-23,1% (3/13), “good”-69,2% (9/13), “satisfactory”-7,7% (1/13), “non-satisfactory”-0. We conclude that using of module endoprosthesis allows achieving good functional results with low rate postoperative complication.
Infection of total knee replacement (TKR) is considered a devastating complication, which necessitates complete removal and thorough debridement of the site. Usually long term antibiotic treatment and a multitude of surgical interventions within a period of several months are required until a definitive supply can be achieved. Osseous defects are common in such conditions and need to be addressed during re-implantation. Managing removal, debridement, reconstruction and re-implantation within a single operation is the ideal solution, both for the patient and the treating team, but rarely executed due to the fear of re-infection. Allograft bone may be impregnated with high loads of antibiotics using a special incubation technique. The resulting antibiotic bone compound (ABC) provides high and long lasting antibiotic levels at the site of infection and is likely to restore bone stock. We have investigated the results of one-stage exchange of infected TKR using ABC together with uncemented implants. Between 1998 and 2004 nineteen exchange procedures of infected TKRs were performed in a single stage, all of them without the use of bone cement. After removal of the implants and radical debridement bone voids were filled with ABC using a modified impaction technique. Consequently, new uncemented implants were inserted. We mainly used the revision type of the LCS knee (DePuy, J&
J) as long as ligamentary stability was considered sufficient. Otherwise, we used a custom-made uncemented version of the LINK Rotational Endo Model. Joints were drained and closed immediately; rehabilitation did not differ from uninfected revision. One knee required re-revision because of persisting infection. The remaining 18 patients stayed infect-free for a period between 2 and 8 years after surgery. In two knees loosening was found after one year, once of the tibial and once of the femoral component. Both were found infect-free at the time of re-revision. All could be successfully revised using the same technique again. No adverse side effects could be found. Incorporation appeared as after grafting with unimpregnated bone grafts. Using antibiotic-impregnated allografts eradication of pathogens, grafting of defects and re-insertion of an uncemented prosthesis may be accomplished in a one-stage procedure. Since the graft gradually is replaced by healthy own bone, improved long-term results may be expected as well as improved conditions in the case of another revision.
Primary bone tumours of the distal radius are rare, while it remains the third commonest site for primary lesions and recurrences of Giant Cell Tumours (GCT). The functional demands on the hand make reconstruction of the wrist joint following the excision of distal radius, particularly challenging. A single-centre retrospective study, reporting the functional and oncological outcomes of six patients (4 males, 2 females - mean age of 53 (22 to 79)) who underwent a custom-made endoprosthetic replacement of the distal radius with arthrodesis at our institution, during 1999 - 2010. Five patients were diagnosed with primary bone sarcoma of the distal radius (4 GCTs, 1 osteosarcoma) and another had a metastatic lesion from a primary renal cell carcinoma. The diagnosis was confirmed by needle biopsy in all cases. We assessed the patients' functional outcomes using the Musculoskeletal Tumour Society scoring system (MSTS) and the Toronto Extremity Salvage Score (TESS).Introduction
Methods
The aim of this study is to evaluate the early results of gleno-humeral reconstruction after tumour excision with a new design of endoprosthesis. The prosthesis is a fixed fulcrum gleno-humeral replacement consisting of a hydroxyapatite (HA) coated glenoid component with a polyethylene liner and a cemented stem with HA coated collar. Between 1997 and 2000 we inserted the prosthesis into 15 patients with primary bone tumours of the proximal humerus. There were nine males and six females with a mean age of 38 years (range: 8–71 years). Twelve stems were cemented and three uncemented. Two skeletally immature patients had an extendible stem inserted, one subsequently having a successful lengthening procedure. The mean follow-up was 28 months (range: 12–41 years). Functional outcome was assessed using the Musculoskeletal Tumour Society (MTS) scoring system. There were two early dislocations and one superficial wound infection. Three patients died of their disease and one underwent forequarter amputation for local recurrence. The remaining eleven had satisfactory functional outcomes with a mean MTS score of 81%. Radiologically there has been no evidence of early loosening. Microscopic analysis of the components in the amputated arm showed excellent osseointegration around the HA coated components.
The recently published Prophylactic Antibiotic Regimens In Tumor Surgery (PARITY) trial found no benefit in extending antibiotic prophylaxis from 24 hours to five days after endoprosthetic reconstruction for lower limb bone tumours. PARITY is the first randomized controlled trial in orthopaedic oncology and is a huge step forward in understanding antibiotic prophylaxis. However, significant gaps remain, including questions around antibiotic choice, particularly in the UK, where cephalosporins are avoided due to concerns of Cite this article:
Endoprosthetic reconstruction following distal femur tumour resection has been widely advocated. In this paper, we present the design of an uncemented endoprosthesis system featuring a short, curved stem, with the goal of enhancing long-term survivorship and functional outcomes. This study involved patients who underwent implantation of an uncemented distal femoral endoprosthesis with a short and curved stem between 2014 and 2019. Functional outcomes were assessed using the 1993 version of the Musculoskeletal Tumour Society (MSTS-93) score. Additionally, we quantified five types of complications and assessed osseointegration radiologically. The survivorship of the endoprosthesis was evaluated according to two endpoints. A total of 134 patients with a median age of 26 years (IQR 16 to 41) were included in our study. The median follow-up time was 61 months (IQR 56 to 76), and the median functional MSTS-93 was 83% (IQR 73 to 91) postoperatively.Aims
Methods
For younger patients many surgeons recommend femoral neck endoprostheses as alternative to stemmed implants in THA. Due to metaphyseal anchorage several advantages are quoted, e.g. preservation of the femoral diaphysis for a revision implant. Determinant factor for long-term implant stability is the load transmission to the bone. Because so far only few information about the load transfer of femoral neck endoprostheses exist, a photoelastic analysis was performed. Aim of the study was the comparison of bony strain pattern before and after implantation of a femoral neck endoprosthesis. ‘Composite-femurs’ (Pacific Research Labs) were used due to of their mechanical characteristics close to human femurs but better reproducibility. Three femurs were coated with photoelastic material. The femurs were loaded prior and post implantation of a femoral neck endoprosthesis type Cigar (ESKA Implants). Test load consisted of the resulting hip joint force and muscle forces (abductors, tractus iliotibialis). Load was applied statically by a universal testing machine and additional weights. Bony strain was measured along the medial, ventral, lateral and dorsal cortex. Statistical analysis of the implant related strain alterations was based on a 99% confidence interval. The unresected femurs showed an excellent match of bony strain patterns. Implantation of femoral neck endoprostheses caused highly significant strain changes at the trochanteric region. Greatest differences were observed at the lateral cortex. Above the implant’s traction screw former areas of tension changed to compression. Along the medial cortex below the resection plane strain reductions were measured but disappeared at the latest at 40 mm below. No significant changes in strain were detected at the ventral and dorsal cortex. Implant related bony strain alterations were limited to the trochanteric region of the femur. A marked strain alteration at the lateral trochanteric aspect was measured. Whether this is of clinical importance can not be answered yet.
We aim to report the clinical and radiological outcome of consecutive primary hip arthroplasties using the JRI-Furlong HAC coated femoral and acetabular components. We reviewed 586 consecutive cementless primary THA in 542 patients with a minimum 12-18 year follow-up, performed at one institution between 1986 and 1994. Twenty-eight (32 THA) were lost to follow-up. Clinical outcome was measured using Harris, Charnley and Oxford scores. Quality of life using EuroQol EQ-5D. Radiographs were systematically analysed. The mean age was 75.2 years. Dislocation occurred in 12 patients (three recurrent). Re operations were performed in 11 patients (1.9%). Four acetabular and one stem revisions were performed for aseptic loosening. Other re-operations were for infection (two), periprosthetic fractures (two), cup malposition (one), revision of worn liner (two). The mean Harris and Oxford scores were 89 (79–96) and 18.4 (12–32) respectively. The Charnley score was 5.7 for pain, 5.3 for movement and 5.4 for mobility. Acetabular radiolucencies were present in 54 hips (9.7%). The mean linear polythene wear was 0.06 mm/year. Stable stem by bony ingrowth was identified in all hips excluding one femoral revision case. Mean stem subsidence was 2.2mm (0.30–3.4mm). Radiolucencies were present around 37 (6.6%) stems. EQ- 5D description scores and health thermometer scores were 0.81 (0.71–0.89) and 86 (64–95). With an end point of definite or probable loosening, survival at 12 years was 96.1% for acetabular and 98.3% for femoral components. Overall survival at 12 years with removal or repeat revision of either component for any reason as the end point was 97.2%. The results of this study support the continued use of a fully coated prosthesis and documents the durability of the HAC coated components. In our clinical experience, the Furlong prosthesis revealed encouraging radiographic stability over a long-term period.
There are results of our first experience treatment 8 patients who underwent endoprosthetic reconstruction of distal radius after excision of malignant tumors. All patients were treated in Sytenko Institute from 2004 to 2008 and had about 5 years follow-up. There are 3 males and 5 females and the median age at diagnosis was 36 (17–55) years. The resection length measured a mean of 8cm and was measure by radiographs, CT and MRI. Each case was malignant Giant cell tumor. There were 5 cases of primary tumor and 3 cases of local tumor relapse. The patients have had chemotherapy, tumor excision and individual custommade endoprosthetic reconstruction. Unfortunately all patients had one-two surgeries before treatment in our Clinic. We used author’s individual custommade endoprosthetsis which was performed from titanium and ceramic spraying. CT-measurement scale was used for preoperative planning and manufacture this distal radius prosthesis. One patient has had deep soft tissue infection and we were needed to remove prosthesis. One more patient had proximal radius fracture 4 month after surgery and we performed bone plate osteosynthesis. All patients (except one infection case) have satisfactory wrist range of motion and functional result of upper limb from 10 month to 5 years follow-up. It is proved that surgical procedure of the tumors of distal radius is a useful and main method of the treatment above-stated localization. The individual custommade prosthesis have a good perspectives for upper limb salvage surgery and reconstruction this area, allowing to receive good oncological and functional results.
Limb salvage has become the most important treatment for patients with malignant bone tumors of the lower limb. Reconstruction with endoprosthesis of the proximal femur and distal femur and proximal tibia is now the most common solution. The data of 180 consecutive patients with malignant bone tumors of the lower limbtreated between 4/1987 and 11/1998 were reviewed. The average follow up is of four years. 129 patients had surgery for primary bone sarcoma, six for aggressive GCT and 45 for metastatic carcinoma. 63 patients were reoperated for different complications. The main complications were: local recurrences in 10 patients, infection in 12 patients and mechanical complications in 35 patients. 28 patients were operated two times and 24 patients more than two times. 14 patients have undergone amputation: six because of local recurrences, four because of infection, and two for post-surgical ischemia. Eight of the 12 infections occurred after a re-operation. 35 patients had mechanical complications: 14 patients were reoperated to replace the polyethylene bushings in of the first model of HMRTS prosthesis (Howmedica), five patients had ruptures of the femoral stem, three patients suffered mobilization of the tibial stem and two of the femoral stem, six patients required a patella prostheses for local pain. Two patients had acetabulum wear and three had hip dislocation. In our experience endoprosthesis reconstruction after resection of bone tumors of the lower limb is a feasible procedure for limb salvage. We must consider that more than 30% of these patients will be re-operated for different complications and that 50% of infections occours after a new surgical procedure.
From 1992 on 2008, 615/515 patients underwent primary or revisional endoprosthetic replacement of major joints. In 51 patients (31 men &
20 women) modular system MUTARS (Implantcast, Germany) has been used. The median age was 23.3 years (15 to 52 years). MUTARS modular endoprosthesis has been used in 10 patients with deep infection of endoprosthetic bed as a revisional endoprosthetic replacement: 1 Total endoprosthetic replacement of femur, 5 Total knee joint replacement (2 for distal femoral defect and 3 for proximal tibial defect). In 3(27%) patients, we used newly patented silver ion coated MUTARS either after two stage treatment for infection of endoprosthetic bed or as a prophylaxis of endoprosthetic infection. In 1 patient (23 yrs), with 12cm limb length shortening, we used extensible MUTARS as a revisional endoprosthetic replacement. The following complications we observed: Instability of endoprosthesis – 3/51 (5.9%), deep endoprosthetic bed infection – 4/51 (7.8%). In comparison group, when using custom-made endoprosthesis, the frequency of infectious complications have made 60/574 (10.5 %), and instability of implants was observed in 79/574 (13.8 %) cases. Transition of using modular systems for primary and revisional endoprosthesis allows to reduce the level of instability from 13.8 % to 5.9 %. The quantity of infectious complications is also not great as in comparison with control group. For revisional endoprosthetic replacement, we think, the given modular system is optimal, for correcting limb length deficiency and restoration of basic function at patients. Use of silver ion coated modular implants is a promising method for treating deep endoprosthetic bed infection.
The purpose of this study was to compare the outcome, complications and survival of the three most commonly used surgical reconstructions of the proximal humerus in adult patients after trans-articular tumour resection. Between1985 and 2005 thirty-eight consecutive proximal humeral reconstructions using either, allograft-prosthesis composite (n=10), osteoarticular allograft (n=13) or a modular tumour prosthesis (n=14), were performed in our clinic. Their mean follow-up was ten years (nine months to 25 years). Of these, twenty-seven were disease free at latest follow-up (Mean follow-up 16.8 years) and ten had died of disease (4.2 years). Complications and implant survival with revision surgery as end-point are presented for the total group of patients, functional scores for surviving patients only. The endoprosthetic group presented the smallest complication rate of 21%, compared to 40% in the allograftprosthesis- composite and 62% in the osteoarticular allograft group. Only one revision was performed in the endoprosthetic group, in a case of shoulder instability. Infection after revision (n=3), pseudoarthrosis (n=2), fracture of the allograft (n=3), and shoulder instability (n=4) were major complications of allograft use in general. Kaplan-Meier-analysis showed a significantly better implant survival for the endoprosthetic group (log-rank p=0.002). At final follow-up the MusculoSkeletal Tumour Society scores averaged at; 72% for the allograft-prosthetic-composite (n=7, mean follow-up 19 years), 76% for the osteoarticular allograft (n=3, 16 years), and 77% for the endoprosthetic reconstruction (n=10, 6 years) groups.Method
Results
We are reporting our case series of lumbar total disc endoprostheses. Oswestry and SF-36 scores were obtained from patients preoperatively and postoperatively for discs in situ for six, twelve and twenty-four months. Oswestry scores improved from fifty-three to thirty-two at six months (N=34); fifty-five to thirty-one at twelve months (N=28); and fifty-two to twenty-five at twenty-four months (N=17). SF-36 scores improved from thirty to fifty-four (physical) and forty to sixty-two (mental) at six months; twenty-nine to fifty-five (physical) and thirty-eight to sixty-three (mental) at twelve months; and twenty-nine to sixty-two (physical) and forty-one to sixty-seven (mental) at twenty-four months. We report our results using the Charité III Endprosthesis in the treatment of degenerative disc disease. Short term outcome for patients having undergone total disk arthroplasty support cautious optimism for continued implantation. Continued close follow-up is essential Total disk arthroplasty for the treatment of degenerative disc disease is increasing in popularity. Expected FDA approval of several implants make accurate functional outcome reports essential to guide practice. Disc replacements in situ for six months (N=34) improved in Oswestry scores from fifty-three to thirty-two. SF-36 physical scores for the same cohort improved from a mean of thirty to fifty-four and mental scores from forty to sixty-two. At one year (N=28), Oswestry scores improved from fifty-five to thirty-one. SF-36 physical scores improved from twenty-nine to fifty-five, and mental scores from thirty-eight to sixty-three. At two years (N=17), Oswestry scores improved from fifty-two to twenty-five. SF-36 physical scores improved from twenty-nine to sixty-two, and mental scores from forty-one to sixty-seven. Using very narrow indications for application of this technique we have implanted fifty-one total disc arthroplasties. Cohorts were analyzed for outcome based on duration in situ of the implant. Through careful follow-up we have identified the following trends based on validated objective outcome measures including the Oswestry low back index and the Short Form 36. These outcome measures in addition to data reported separately demonstrating clear maintenance of interdiscal lumbar range of motion allow for cautious optimism regarding the continued application of total disc arthroplasty.
Several methods have been used for proximal humeral reconstruction following tumour resection. None of these modalities allow the patient to regain his normal shoulder range of motion. Moreover, every modality has its advantages and disadvantages. The aim of this study was to compare the functional outcome of 2 reconstructive modalities that we are using in our institution for proximal humeral reconstruction; endoprosthesis and shoulder arthrodesis using a vascularised autograft This study included 48 patients diagnosed with malignant or benign aggressive tumours that required resection of their proximal humerus. They were divided into 2 groups according to the method of reconstruction. Group 1 included 22 patients with an average age of 20 years were reconstructed by shoulder arthrodesis using a free vascularised fibular graft (6) or a pedicled scapular crest graft (16). Group 2 included 26 patients with an average age of 26 years were reconstructed with an endoprosthesis. In group 1 the average follow up period was 88 months (range 12 to 184 months). The average functional outcome (according to the MSTS scoring system) was 25 points (range 19 – 28). The average abduction and forward flexion range of motion (scapulothoracic) was 40 degrees (range 20 -60). Complications included failed fixation (2), non union (1), infection (1) and temporary radial nerve palsy (2). In group 2 the average follow up period was 36 months (range 12 – 110). The average functional outcome was 24 points (range 20 – 27). The average abduction and forward flexion range of motion was 40 (range 30 –70). Complications included sublaxation (2), loosening (1) and infection (1). Reconstruction of the proximal humerus by arthrodesis or endoprosthesis yield similar functional outcome. Although endoprosthesis is a much more expensive modality, it does not provide any superior functional outcome over shoulder arthrodesis.
Frequent imaging after a completed multimodal therapy of osteosarcoma is recommended by therapy optimization studies to detect local or systemic tumor recurrence. Considering the low rates of local recurrence, regular local imaging has to be questioned. 150 patients with osteosarcoma were treated in our department between 1991 and 2005. The median age of patients with osteosarcoma was 17 years with a range of 4 – 79 years and a female:male ratio of 1:1.1. The primary tumors of 147 patients were treated surgically, while 3 patients refused to be operated. After a wide resection, a tumor endoprosthesis was implanted in 103 (70.1%) of the 147 patients, 16 (10.9%) patients underwent a Borggreve rotationplasty, a resection and biological reconstruction was implemented in 10 (6.8%) patients, while further 18 (12.2%) patients were amputated. The median follow up was 95 months. Local recurrences appeared in 2 (1.4%) patients which had been treated with a hemipelvectomy. After implantation of a tumor endoprosthesis, local recurrences were not observed. Postoperative complications observed after the implantation of a tumor endoprosthesis included infections (n=14; 13.6%), loosening, fractures and wearing of endoprotheses (n=7; 4.8%), luxation (n=1; 0.7%) as well as traumatic shaft fractures of involved bones (n=5; 3.4%). All complications included specific symptoms and were diagnosed outside the routine follow up. In conclusion, local radiological imaging after resection of an osteosarcoma and reconstruction with a tumor endoprosthesis as a routine examination should be questioned, however it is definitely indicated in patients with specific symptoms.
Debate continues regarding the optimum management of periprosthetic distal femoral fractures (PDFFs). This study aims to determine which operative treatment is associated with the lowest perioperative morbidity and mortality when treating low (Su type II and III) PDFFs comparing lateral locking plate fixation (LLP-ORIF) or distal femoral arthroplasty (DFA). This was a retrospective cohort study of 60 consecutive unilateral (PDFFs) of Su types II (40/60) and III (20/60) in patients aged ≥ 60 years: 33 underwent LLP-ORIF (mean age 81.3 years (SD 10.5), BMI 26.7 (SD 5.5); 29/33 female); and 27 underwent DFA (mean age 78.8 years (SD 8.3); BMI 26.7 (SD 6.6); 19/27 female). The primary outcome measure was reoperation. Secondary outcomes included perioperative complications, calculated blood loss, transfusion requirements, functional mobility status, length of acute hospital stay, discharge destination and mortality. Kaplan-Meier survival analysis was performed. Cox multivariate regression analysis was performed to identify risk factors for reoperation after LLP-ORIF.Aims
Methods
This case highlights the close association between osteo-fibrous dysplasia (OFD) and adamantinoma, drawing attention to the role for more radical treatment options when treating OFD. We discuss the advancements in joint-sparing endoprostheses using bicortical fixation. Finally we describe a unique biomedical design allowing for manufacture of an end cap to allow amputation through a custom made joint-sparing proximal tibial replacement as opposed to an above knee amputation. A 37 year old presented 7 years ago having sustained a pathological fracture of her tibia. Subsequent biopsy revealed OFD, curettage with bone graft was performed. She later developed recurrence, two percutaneous biopsies confirmed OFD. 6 years following her initial diagnosis she was referred to RNOH with further recurrence, a biopsy at this stage revealed a de-differentiated adamantinoma. A joint-sparing proximal tibial replacement was performed and adjuvant chemotherapy administered, she remained well for one year. Recurrence was noted at the distal bone-prosthesis interface, histology revealed a high grade dedifferentiated osteosarcoma, limb preservation was not deemed possible and an amputation was performed through the prosthesis. The proximal tibial device was uncoupled leaving a residual 7 cms insitu, a small custom made end cap was attached to the remaining prosthesis and a myocutaneous flap fashioned over it, this ultimately enabled the patient to mobilise well with a below–knee orthotic device. This case highlights the need for more radical surgery when treating cases of OFD and the relationship between OFD and adamantinoma. It also introduces a joint-sparing proximal tibial device for use in proximal tibial tumours that do not invade the proximal tibial metaphysis. The biomechanical design solution has given us the unique option of preserving the knee joint allowing the patient a below knee amputation whereas previously an above knee amputation would have been performed thereby significantly reducing her functional outcome.
Instability of the hip is the most common mode of failure after
reconstruction with a proximal femoral arthroplasty (PFA) using
an endoprosthesis after excision of a tumour. Small studies report
improved stability with capsular repair of the hip and other techniques,
but these have not been investigated in a large series of patients.
The aim of this study was to evaluate variables associated with
the patient and the operation that affect post-operative stability.
We hypothesised an association between capsular repair and stability. In a retrospective cohort study, we identified 527 adult patients
who were treated with a PFA for tumours. Our data included demographics,
the pathological diagnosis, the amount of resection of the abductor
muscles, the techniques of reconstruction and the characteristics
of the implant. We used regression analysis to compare patients
with and without post-operative instability.Aims
Patients and Methods
We aimed to examine the long-term mechanical survivorship, describe the modes of all-cause failure, and identify risk factors for mechanical failure of all-polyethylene tibial components in endoprosthetic reconstruction. This is a retrospective database review of consecutive endoprosthetic reconstructions performed for oncological indications between 1980 and 2019. Patients with all-polyethylene tibial components were isolated and analyzed for revision for mechanical failure. Outcomes included survival of the all-polyethylene tibial component, revision surgery categorized according to the Henderson Failure Mode Classification, and complications and functional outcome, as assessed by the Musculoskeletal Tumor Society (MSTS) score at the final follow-up.Aims
Methods
Aseptic loosening is a major cause of failure in cemented endoprosthetic reconstructions. This paper presents the long-term outcomes of a custom-designed cross-pin fixation construct designed to minimize rotational stress and subsequent aseptic loosening in selected patients. The paper will also examine the long-term survivorship and modes of failure when using this technique. A review of 658 consecutive, prospectively collected cemented endoprosthetic reconstructions for oncological diagnoses at a single centre between 1980 and 2017 was performed. A total of 51 patients were identified with 56 endoprosthetic implants with cross-pin fixation, 21 of which were implanted following primary resection of tumour. Locations included distal femoral (n = 36), proximal femoral (n = 7), intercalary (n = 6), proximal humeral (n = 3), proximal tibial (n = 3), and distal humeral (n = 1).Aims
Patients and Methods
The use of a noninvasive growing endoprosthesis in the management
of primary bone tumours in children is well established. However,
the efficacy of such a prosthesis in those requiring a revision
procedure has yet to be established. The aim of this series was
to present our results using extendable prostheses for the revision
of previous endoprostheses. All patients who had a noninvasive growing endoprosthesis inserted
at the time of a revision procedure were identified from our database.
A total of 21 patients (seven female patients, 14 male) with a mean
age of 20.4 years (10 to 41) at the time of revision were included.
The indications for revision were mechanical failure, trauma or infection
with a residual leg-length discrepancy. The mean follow-up was 70
months (17 to 128). The mean shortening prior to revision was 44 mm
(10 to 100). Lengthening was performed in all but one patient with
a mean lengthening of 51 mm (5 to 140).Aims
Patients and Methods
Enhanced micromotions between the implant and surrounding bone can impair osseointegration, resulting in fibrous encapsulation and aseptic loosening of the implant. Since the effect of micromotions on human bone cells is sparsely investigated, an Micromotions ranging from 25 µm to 100 µm were applied as sine or triangle signal with 1 Hz frequency to human osteoblasts seeded on collagen scaffolds. Micromotions were applied for six hours per day over three days. During the micromotions, a static pressure of 527 Pa was exerted on the cells by Ti6Al4V cylinders. Osteoblasts loaded with Ti6Al4V cylinders and unloaded osteoblasts without micromotions served as controls. Subsequently, cell viability, expression of the osteogenic markers collagen type I, alkaline phosphatase, and osteocalcin, as well as gene expression of osteoprotegerin, receptor activator of NF-κB ligand, matrix metalloproteinase-1, and tissue inhibitor of metalloproteinase-1, were investigated.Objectives
Methods