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We have made a retrospective study of 1001 custom-made prostheses used as replacements after surgery for bone tumours. There were 493 distal femoral, 263 proximal femoral and 245 proximal tibial prostheses. Aseptic loosening was shown to be the principal mode of failure of the implants, and 71 patients had revision for aseptic loosening of a cement...
Contexts in source publication
Context 1
... (Ti 318, Ti6Al4V), and, when indicated, the stem was shaped to follow the natural curva- ture of the bone. Both the distal femoral and proximal tibial prostheses used the Stanmore fully-constrained knee hinge and were made from cast cobalt-chrome-molybdenum alloy. The proximal femoral replacements had cobalt- chrome-molybdenum alloy femoral heads (Fig. ...
Context 2
... clinical study of a proximal femoral replacement fitted with strain gauges and telemetric apparatus has shown that 60% of the applied load on a cemented intramedullary stem was transferred to the region of the tip of the stem which had been in position for 100 weeks (Taylor et al 1993). Initially, the ratio of the strain in the stem tip to that in the shaft was 0.25: this rose steadily up to 30 weeks and then tended to level off to approximately 0.60 at around 60 weeks. ...
Similar publications
Stems improve the mechanical stability of tibial components in total knee replacement (TKR), but come at a cost of stress shielding along their length. Their advantages include resistance to shear, reduced tibial lift-off and increased stability by reducing micromotion. Longer stems may have disadvantages including stress shielding along the length...
Citations
... 5, 6 We decided to restore at least 40% of the bone as it has been pointed as a critical amount of bone for reducing aseptic loosening of a cemented knee megaprosthesis. 5,11 The technique of telescopic augmentation has been represented in Figures 1 and 2. In all cases, the prosthetic stem was cemented, with plain, medium viscosity cement. ...
Background and Objective
Oncological distal femur resections can leave a proximal femur too short to host a stem. Reconstructive techniques are then challenging. The purpose of the study is to compare implant survival, complication rate and MSTS of two different options.
Methods
We retrospectively divided 33 patients with primary bone tumours of distal femur in Group 1 (16 patients reconstructed with knee megaprosthesis with proximal bone augmentation, APC) and Group 2 (17 patients reconstructed with total femur prosthesis, TFP). Less than 12 cm of remaining proximal femur were planned for all resections.
Results
MSTS score at 2 years is 25 ± 5 for Group 1 and 19 ± 7 for Group 2 (confidence interval [C.I.] 95%, p = 0.02). At 5 years it is 27 ± 2 for Group 1 and 22 ± 6 for Group 2 (C.I. 95%, p = 0.047). Failure and complication rates are lower for Group 1, but no statistical significance was reached. In APC reconstruction, union at the host‐allograft junction was achieved in 16 out of 16 patients using the telescopic bone augmentation technique.
Conclusions
APC provides higher functional results compared to TFP after extended distal femur resection. In APC reconstruction, telescopic augmentation is excellent for achieving union at the host‐allograft junction.
... Despite our cohort's cement mantles falling within the ideal range, aseptic loosening remained the most common type of cemented stem failure in our patients, which is partially consistent with the literature because infection is recognized and proved to be the most common mode of failure. 3,8,13,14 Age is a patient factor that has been associated with failure in cemented stems. Several studies have found that cemented stems were at higher risk of aseptic loosening in younger patients. ...
... Several studies have found that cemented stems were at higher risk of aseptic loosening in younger patients. 13,14 The utilization of adjuvant therapy has markedly improved the survival outcomes for patients diagnosed with primary bone malignancies. 6 Consequently, these patients undergo arthroplasty at a younger age and maintain their prosthetic implants for extended periods compared with those undergoing standard arthroplasty for nononcologic indications. ...
... Moreover, these patients impose additional demands on their implants, particularly concerning their level of physical activity. 6,14 Jasty et al found cement debonding at the prosthesis interface to be common, over time leading to cement mantle fracture and ultimately longterm failure. 5 Between the increased physical demand and natural course of the cement, the life span of the patient may exceed the survival of the implant. ...
Background
Stem fixation in reconstruction after resection of femoral tumors is debated. Cemented stems offer immediate stability but risk aseptic loosening, while press-fit stems allow bone ingrowth but risk stress shielding and subsidence. Our retrospective review aimed to determine implant failure rates and their associated factors, as well as the rates of infection, debridement, and mortality for both fixation groups (cemented or press-fit stems) used in patients undergoing resection of femoral tumor disease and subsequent arthroplasty.
Methods
We retrospectively studied 252 patients who underwent resection of femoral tumors and subsequent arthroplasty using cemented (n = 173; 69%) or press-fit (noncemented) (n = 79; 31%) stems between 1999 and 2020. Implant failure was the primary outcome, with secondary outcomes including rates of implant infection, debridement, and mortality. Multivariable regression was done to assess risk factors for implant failures.
Results
The study found implant failure rates of 11% and 18% for cemented stems and press-fit stems, respectively. Lower stem to diaphyseal ratios ( P = 0.024) and younger patients ( P = 0.008) were associated with a higher risk of implant failure in cemented stems. The infection rates were 14% and 10% for cemented and press-fit stems, respectively. Debridement rates were 16% and 13% for cemented and press-fit stems, respectively, while the 1-year mortality rate was 16% for cemented stems and 1.5% for press-fit stems.
Conclusions
This study is the largest of its kind, providing patient characteristics and outcomes in both cemented and press-fit stems in the setting of reconstruction for femoral tumors. Both methods can be effective, with outcomes dependent on patient-specific factors, such as life expectancy, activity level, and body habitus, as well as proper implant fit. Additional studies of both implants and longer follow-up are required to elucidate the optimal fixation method for each individual patient.
Level of evidence
Level III, retrospective noncomparative study.
... In a study of 661 EPRs, aseptic loosening accounted for 25% of revisions [1]. Two other studies reported similar aseptic loosening to be the major failure mechanism of EPRs, with rates of loosening of 2.9% and 28.6% after 4 and 10 years, respectively [9,10]. ...
... Aseptic loosening of EPRs is associated with the loss of cortical bone (osteolysis). The process initiates at the boneprosthesis interface and progresses along the stem [10]. This could be countered, in theory, by having a region of bone ongrowth over the shoulder of the prosthesis at the bone-prosthesis interface to promote osseointegration, a process described as extracortical bone bridging [11,12]. ...
Background
Limb-salvage surgery involving the utilization of endoprosthetic replacements is commonly employed following segmental bone resection for primary and secondary bone tumors. This study aimed to evaluate whether a fully porous bridging collar promotes early osseous integration in endoprosthetic replacements.
Methods
We undertook a retrospective review of all lower-limb endoprostheses utilizing a fully porous endosteal bridging collar design. We matched this cohort with a conventional extra-osteal non-porous fully hydroxyapatite-coated grooved collar cohort according to surgical indication, implant type, resection length, age, and follow-up time. At 6, 12, and 24 months post-implantation, radiographs were assessed for the number of cortices with or without osseointegration on orthogonal radiographs. Each radiograph was scored on a scale of -4 to + 4 for the number of cortices bridging the ongrowth between the bone and the collar of the prosthesis. Implant survival was estimated using the Kaplan–Meier method, and the mean number of osseointegrated cortices at each time point between the collar designs was compared using a paired t-test.
Results
Ninety patients were retrospectively identified and analyzed. After exclusion, 40 patients with porous bridging collars matched with 40 patients with conventional extra-osteal non-porous collars were included in the study (n = 80). The mean age was 63.4 years (range 16–91 years); there were 37 males and 43 females. The groups showed no difference in implant survival (P = 0.54). The mean number of cortices with radiographic ongrowth for the porous bridging collar and non-porous collar groups was 2.1 and 0.3, respectively, at 6-month (P < 0.0001), 2.4 and 0.5, respectively, at 12-month (P = 0.044), and 3.2 and -0.2, respectively, at 24-month (P = 0.18) radiological follow-up.
Conclusion
These findings indicate that fully porous bridging collars increased the number of cortices, with evidence of bone ongrowth between 6 and 24 months post-implantation. By contrast, extra-osteal collars exhibited reduced evidence of ongrowth between 6 and 24 months post-implantation. In the medium term, the use of a fully porous bridging collar may translate to a reduced incidence of aseptic loosening.
Graphical Abstract
... In some of the first megaprostheses of proximal femur, intramedullary stems were furtherly stabilized with flanges that fit over the cortex [6]. Stem cementification has been largely used since the 1960s to secure the bone-prosthesis interface [7], while press-fit implants were a more recent innovation, targeted to achieve a better integration and minimize the risk of aseptic loosening that burdened cemented prostheses [8]. ...
Background
Reconstructions of the proximal femur after massive resections represent one of the main challenges in orthopedic oncology. Among the possible treatments, megaprostheses represent one of the most used and reliable reconstructive approaches. Although literature about their outcomes has flourished through the last decades, a consensus rehabilitative treatment is still far from being established.
Materials and methods
We evaluated the functional results of all our oncologic cases treated between 2016 and 2022 that could follow our standardized post-operative rehabilitative approach, consisting in progressive hip mobilization and early weight-bearing.
Results
Twenty-two cases were included in our study. On average, their hospitalization lasted 15.1 days. The seated position was achieved on average within 3.7 days after surgery, the standing position reached 5.4 after surgery, while assisted deambulation was started 6.4 days after surgery. After a mean post-operative follow-up of 44.0 months, our patients’ mean MSTS score was 23.2 (10–30). Our data suggested a statistically significant inverse linear correlation between post-operative functionality and patients’ age, resection length, and the start of deambulation.
Conclusions
A correct rehabilitation, focused on early mobilization and progressive weight-bearing, is crucial to maximize patients’ post-operative functional outcomes.
... Regarding the medium-term outcomes of cemented TKA, the results of this study are consistent with the literature, which indicates favorable clinical outcomes and high implant survival rates for cemented TKA [17]. The low incidence of aseptic loosening observed in this study aligns with the generally accepted success of cemented TKA implants in achieving long-term stability and survival [18]. ...
Background: This study aimed to evaluate the survival rate and medium-term outcomes of patients after cemented posterior-stabilized (PS) mobile-bearing (MB) total knee arthroplasty (TKA) using a telemedicine platform during the COVID-19 pandemic in Italy. Methods: A total of 100 consecutive patients (mean age 73.5 ± 13.2 years) who received a cemented PS MB TKA were enrolled. The mean age of patients who did not complete the telemedicine follow-up (58%) was 75.8 ± 9.7 years. A dedicated software that makes it possible to perform video calls, online questionnaires, and acquire X-rays remotely was used. Subjective clinical scores and objective range-of-motion (ROM) measurements were observed at an average follow-up of 54 ± 11.3 months. Results: A total of 42 of 100 enrolled patients (mean age 70.3 ± 8.4 years) completed the telemedicine follow-up. The mean age of patients who did not complete the telemedicine follow-up (58%) was 75.8 ± 9.7 years. Age was found to be a statistically significant difference between the group that completed the telemedicine follow-up and the one that did not (p < 0.004). KOOS scores improved from 56.1 ± 11.3 to 77.4 ± 16.2, VAS scores decreased from 7.2 ± 2.1 to 2.8 ± 1.6, KSSf scores increased from 47.2 ± 13.3 to 77.1 ± 21.1, FJS scores improved from 43.4 ± 12.3 to 76.9 ± 22.9, and OKS scores increased from 31.9 ± 8.8 to 40.4 ± 9.9. All the differences were statistically significant (p < 0.05). The mean flexion improved from 88° ± 8° to 120° ± 12°. A radiographic evaluation showed a mean pre-operative mechanical axis deviation of 5.3 ± 8.0 degrees in varus, which improved to 0.4 ± 3.4 degrees of valgus post-operation. The survivorship at 5 years was 99%. Conclusions: Subject to small numbers, telemedicine presented as a useful instrument for performing remote monitoring after TKA. The most important factor in telemedicine success remains the patient’s skill, which is usually age-related, as older patients have much more difficulty in approaching a technological tool.
... The appropriate option for reconstruction of the lower limb after resection of the femur or tibia is controversial (2). Options include the use of autografts (3), allografts (4), custom-made mega prostheses (5), and modular endoprostheses. The functional outcome for patients treated with distal femoral replacement prosthesis generally is thought to be acceptable. ...
Introduction
Gait analysis is one of the most important components of functional outcome evaluation in patients with lower-extremity tumors. Disparities between operated limbs when compared with non-operated limbs and healthy populations based on gait parameters have rarely been studied. In the present study, we attempted to analyze the gait difference and its impacts on daily life.
Methods
The gait parameters of distal femoral tumor-resected patients were collected from PubMed, CNKI, MEDLINE, Embase, Cochrane, and Google Scholar till September 30, 2022, by strictly following the inclusion and exclusion criteria. Differences between gait parameters in the operated and non-operated limbs or healthy limbs of distal femoral tumor patients were analyzed based on stance phase, swing phase, cadence, and velocity. The fixed-effects and random-effects models were used to conduct a meta-analysis.
Results
Six studies were included according to the selection criteria. There were 224 patients in total in these studies. Standard mean differences were calculated for all of our outcomes. Our results showed that there was a minimal difference in the standard mean difference of gait parameters between operated and non-operated limbs and healthy limbs.
Conclusion
Distal femoral tumor resections have been associated with deficient muscle function and strength and impaired gait parameters. Minimal differences in the gait parameters highlighted the advantage of distal femoral resection when replaced with a prosthesis.
... 15) In addition, being the late-period complication, the quality and length of the remnant bone is often compromised due to osteoporosis from disuse, cortical atrophy, or previous revision procedures. 7,16,17) Minimizing the host bone destruction while removing the stem or bone cement is important for restoring proper fixation of the stem. ...
Background
Mechanical failures of tumor endoprosthesis in the distal femur usually require revision surgery. We investigated if the proximal femur host bone can be salvaged by onlay and overlapping allograft in revision surgeries due to aseptic loosening and stem fractures.
Methods
We retrospectively reviewed 18 patients (7 men and 11 women) with osteosarcoma around the knee. The entire cohort was classified into three subgroups (no bone graft: 6, onlay allograft: 7, and overlapping allograft: 5) according to our treatment strategy.
Results
The median interval from the initial surgery to the revision was 94.5 months (range, 21–219 months), and the median follow-up period from the revision surgery was 88.0 months (range, 24–179 months). At the last follow-up, 9 of the 18 patients maintained their endoprostheses, and the 5-year prosthesis survival rate was 57.9%. Limb survival was 100%. Five-year prosthesis survival rate was 66.7% in the no bone graft group, 85.7% in the onlay allograft group while 30.0% in the overlapping allograft group. In the no bone graft group and onlay allograft group, 66.7% (4/6) and 57.1% (4/7) maintained their revision prostheses while no prostheses survived in the overlapping allograft group. Recurrent stem loosening was observed in 14.2% (1/7) and 60.0% (3/5) of the onlay allograft and overlapping allograft groups, respectively, despite allograft bone union. The complication rate was 66.7% (12/18) in the entire cohort. The most common type of complication was infection (n = 6), followed by aseptic loosening (n = 4) and mechanical failure (n = 2).
Conclusions
This study indicates that onlay allograft can be used as a supportive method in revising failed endoprosthesis if the extent of host bone destruction is extensive. However, applying overlapping allograft to secure bone stock showed a high rate of mechanical failures and infection in the long term. Future studies with a larger cohort are necessary to assess the prognostic factors for the higher complication rate in overlapping allograft and the need for overlapping allograft. Surveillance with consideration of the risk of anteromedial osteolysis in allograft and efforts for prevention of periprosthetic infection are essential.
... The difficulty of estimating the precise length and width of the resected bone based solely on imaging modalities was a second disadvantage of custom-made prostheses. 14,15 For all our patients we started physiotherapy (isometric exercises) on 3 rd day. Partial weight bearing was initiated to all patients on day 7 and full weight bearing on pod 10. ...
... However, the clinical efficacy and outcomes of using this technique in osteoarticular reconstruction for fixation of the massive endoprosthesis remain unclear. Previously, resection of an extensive length of bone has been shown associated with implant failure, and the greater the percentage of bone resected, the greater the probability of failure [19]. Therefore, it is necessary and interesting to examine whether 3DP porous short stem is an alternative for short-segment fixation of the massive endoprosthesis. ...
Background
Large malignant bone tumors and revision limb salvage procedures often result in massive bone loss, leaving a short residual bone segment that cannot accommodate a standard stem for endoprosthesis fixation. Three-dimensional-printed (3DP) short stem with porous structure seems to be an alternative for short-segment fixation. This retrospective study aims to evaluate surgical outcomes, radiographical results, limb functions, and complications of using 3DP porous short stems in massive endoprosthesis replacement.
Methods
Between July 2018 to February 2021, 12 patients with massive bone loss undergoing reconstruction with custom-made, short-stemmed massive endoprostheses were identified. Endoprosthesis replacement involved the proximal femur (n = 4), distal femur (n = 1), proximal humerus (n = 4), distal humerus (n = 1), and proximal radius (n = 2).
Results
The mean percentage of resected bone was 72.4% of the whole length of the bone, ranging from 58.4 to 88.5%. The mean length of 3DP porous short stems was 6.3 cm. The median follow-up was 38 months (range, 22–58 months). The mean MSTS score was 89%, ranging from 77% to 93%. Radiographical assessment results showed bone in-growth to the porous structure in 11 patients, and the implants were well osseointegrated. Breakage of the 3DP porous short stem occurred in one patient intraoperatively. The patient developed aseptic loosening (Type 2) four-month after surgery and underwent revision with a plate applied to assist fixation. The implant survivorship was 91.7% at 2 years. No other complications were detected, such as soft-tissue failures, structural failures, infection, or tumor progression.
Conclusions
3DP custom-made short stem with porous structure is a viable method for fixation of the massive endoprosthesis in the short segment after tumor resection, with satisfactory limb function, great endoprosthetic stability, and low complication rates.
... The length of bone resection exerted a significant impact on postoperative function of patients undergoing tumor prosthetic replacement and prosthetic survival rate. 21 Kawai et al. 21 noted that the mean net energy cost during walking was correlated with the percentage of the femur that had been resected (r = 0.504, P = .004). ...
... The length of bone resection exerted a significant impact on postoperative function of patients undergoing tumor prosthetic replacement and prosthetic survival rate. 21 Kawai et al. 21 noted that the mean net energy cost during walking was correlated with the percentage of the femur that had been resected (r = 0.504, P = .004). Patients who underwent an extra-articular resection had lower mean flexor torque (P = .006) ...
Objectives
The restoration of as much normal function as possible has become an important goal following the endoprosthetic reconstruction. The objective of this study was to assess the functional outcome after endoprosthetic reconstruction for tumors around the knee and to explore prognostic factors of functional outcome.
Methods
We retrospectively collected data on patients who underwent tumor prosthetic replacements consecutively. Musculoskeletal Tumour Society score and Toronto Extremity Salvage Score were used to assess the functional outcome at 1, 3, 6, 12, and 24 months after surgery. The logistic model was used to select factors that had potential predictive value for postoperative function. Potential prognostic factors included age, gender, tumor site, type of tumor, length of bone resection, type of prosthesis, length of prosthetic stem, chemotherapy, pathological fracture, and body mass index.
Results
At the 24 months after surgery, the mean musculoskeletal tumor society (MSTS) score was 81.4% and the mean Toronto extremity salvage score (TESS) was 83.6%. At the last follow-up, 68% of patients and 73% of patients received perfect or good MSTS score and TESS score, respectively. The multivariate analysis according to ordered-logit model showed that age < 35 years, distal femoral prosthesis, and length of bone resection < 14 cm were independent prognostic factors of better functional outcome.
Conclusions
Endoprosthetic reconstruction may provide good functional results for most patients. Younger patients with distal femoral prosthesis and shorter resection of bone (on the premise of complete resection of tumor) are more likely to obtain satisfactory functional results after surgery.
