Early postoperative gain in activity levels of lower extremity sarcoma survivors positively affects long-term physical activity and performance.

PURPOSE: Little is known about the effect of sports activity levels on health-related quality of life (HRQOL) in long-term survivors of lower-extremity sarcoma. METHODS: Eighty-three long-term survivors of bone and soft tissue sarcoma of the lower extremities with a median follow-up of 14 (range: 5-35) years completed the University of California and Los Angeles (UCLA) activity scores before tumor resection, 1 year after surgery and at the latest follow-up, as well as a Short Form 36 (SF-36) health survey at the latest follow-up. Simple linear regression models as well as stepwise variable selection with Akaike information criterion (AIC) were undertaken. RESULTS: The preoperative UCLA activity level (median: 9, range: 2-10) dropped to a median of 4 (range: 1-10) 1 year after surgery before increasing to a score of 6 (range: 2-10) 5 years after surgery. The long-term SF-36 physical health component summary score (PCS) was 49 (SD: 9), and the mental health component summary score (MCS) was 54 (SD: 7). A linear model with stepwise variable selection identified a negative correlation of PCS with age at surgery (estimate: -0.2; p = 0.02), UCLA score at the last follow-up (estimate: 1.4; p = 0.02) and UCLA score 1 year after surgery (estimate: 1.0; p = 0.02). CONCLUSION: As not only the final activity levels but also the status immediately after surgery affect the PCS, higher early activity levels should be a goal of modern rehabilitation after sarcoma treatment. Further studies are needed to weigh the potential postoperative risks of higher sport activity levels against the benefits described in this study. LEVEL OF EVIDENCE: Level 4.

Patient-Specific Guides for Accurate and Precise Positioning of Osseointegrated Implants in Transfemoral Amputations: A Proof-of-Concept In Vitro Study.

Background and Objectives: The treatment of transfemoral amputees using osseointegrated implants for prosthetic anchorage requires accurate implant positioning when using threaded bone-anchoring implants due to the curvature of the femur and the risk of cortical penetration in misaligned implants. This study investigated the accuracy and precision in implant positioning using additively manufactured case-specific positioning guides. Materials and Methods: The geometry and density distribution of twenty anatomic specimens of human femora were assessed in quantitative computed tomography (QCT) scanning. The imaging series were used to create digital 3D specimen models, preoperatively plan the optimal implant position and manufacture specimen-specific positioning guides. Following the surgical bone preparation and insertion of the fixture (threaded bone-anchoring element) (OPRA; Integrum AB, Mölndal, Sweden), a second QCT imaging series and 3D model design were conducted to assess the operatively achieved implant position. The 3D models were registered and the deviations of the intraoperatively achieved implant position from the preoperatively planned implant position were analyzed as follows. The achieved, compared to the planned implant position, was presented as resulting mean hip abduction or adduction (A/A) and extension or flexion (E/F) and mean implant axis offset in medial or lateral (M/L) and anterior or posterior (A/P) direction measured at the most distal implant axis point. Results: The achieved implant position deviated from the preoperative plan by 0.33 ± 0.33° (A/A) and 0.68 ± 0.66° (E/F) and 0.62 ± 0.55 mm (M/L) and 0.68 ± 0.56 mm (A/P), respectively. Conclusions: Using case-specific guides, it was feasible to achieve not only accurate but also precise positioning of the implants compared to the preoperative plan. Thus, their design and application in the clinical routine should be considered, especially in absence of viable alternatives.

Specific knowledge and resilience affect short-term outcome in patients following primary total hip arthroplasty.

PURPOSE: The aim of the present study was to investigate the potential associations between specific knowledge, resilience and patient-reported outcome measures (PROMS) following primary total hip arthroplasty (THA). METHODS: In a cross-sectional prospective study, consecutive patients following primary THA were included at a rehabilitation center. A novel knowledge score and the validated Connor Davidson Resilience Scale (CD-RISC) were utilized to assess patients' specific knowledge and resilience, respectively. Additionally, patients completed a qualitative questionnaire regarding the information they had received. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), as well as the University of California and Los Angeles Score (UCLA) served as primary outcome measures. Stepwise multiple regression analysis was performed to identify potential predictors of outcome. RESULTS: A total of 103 patients at a mean age of 67.5 years (SD 10.5, 38-88) were included in the analysis at a median of 55.5 days (IQR 43-81) following primary THA. The mean knowledge and resilience scores were 3.8 (SD 1.6, 0-7) and 69.5 (SD 18.5, 0-100), respectively. Forty-seven percent of patients were afraid of harming their prosthesis and these patients had up to 59% worse WOMAC scores (p < 0.001). WOMAC scores on admission to rehabilitation were predicted by resilience and knowledge scores (R2 = 0.106, p = 0.036). UCLA scores at the time of admission were predicted by knowledge scores (R2 = 0.078, p = 0.007). CONCLUSION: The present study demonstrated that patients with a feeling of uncertainty had an inferior short-term functional outcome following primary THA. Moreover, it could be shown that higher specific knowledge and resilience are associated with a better functional outcome according to validated PROMS. While these findings need to be prospectively validated in future studies, specific patient knowledge and resilience may have a direct impact on the outcome of primary THA.

Is There an Association Between Bone Microarchitecture and Fracture in Patients who were Treated for High-grade Osteosarcoma? A Controlled Study at Long-term Follow-up Using High-resolution Peripheral Quantitative CT.

BACKGROUND: Neoadjuvant chemotherapy in patients with primary osteosarcoma improves survival rates, but it also causes side effects in various organs including bone. Low bone mineral density (BMD) can occur owing partly to chemotherapy or limited mobility. This can cause a higher risk of fractures compared with those who do not receive such treatment. Changes in BMD alone cannot explain the propensity of fractures. Studying microarchitectural changes of bone might help to understand the effect. QUESTIONS/PURPOSES: (1) Do patients who were treated for osteosarcoma (more than 20 years previously) have low BMD? (2) Do these patients experience more fractures than controls who do not have osteosarcoma? (3) What differences in bone microarchitecture are present between patients treated for high-grade osteosarcoma and individuals who have never had osteosarcoma? METHODS: We contacted 48 patients who were treated for osteosarcoma and who participated in an earlier study. These patients underwent multimodal treatment including chemotherapy more than 20 years ago. Of the original patient group, 60% (29 of 48) were missing, leaving 40% (19 of 48) available for inclusion in this study; all 19 agreed to participate. There were nine men and 10 women with a mean age of 46 ± 4 years and a mean time from surgery to examination of 28 ± 3 years. BMD was measured by dual-energy x-ray absorptiometry, and any fracture history was assessed using a questionnaire. Additionally, high-resolution peripheral quantitative CT was performed to compare the groups in terms of microarchitectural changes, such as cortical and trabecular area, cortical and trabecular thickness, cortical porosity, and endocortical perimeter. Participants in the control group were selected from a cohort consisting of a population-based random sample of 499 healthy adult women and men. Osteoporosis or low BMD was not an exclusion criterion for entering this study; however, the patients in the control group were selected based on a normal BMD (that is, T score > -1.0 at both the spine and hip). Also, the participants were matched based on age and sex. Differences between patients and controls were assessed using the Wilcoxon rank sum test for continuous variables and a chi-square test for categorical variables. A multiple regression analysis was performed. Model assumptions were checked using histograms and quantile-quantile plots of residuals. RESULTS: Twelve of 19 patients who were treated for osteosarcoma had either osteopenia (eight patients) or osteoporosis (four patients). More patients with osteosarcoma reported sustaining fractures (11 of 19 patients) than did control patients (2 of 19 controls; p < 0.001). Among all microarchitectural parameters, only the endocortical perimeter was increased in patients compared with the control group (75 ± 15 mm versus 62 ± 18 mm; p = 0.04); we found no differences between the groups in terms of cortical and trabecular area, cortical and trabecular thickness, or cortical porosity. CONCLUSION: Although patients who were treated for osteosarcoma had osteopenic or osteoporotic BMD and a higher proportion of patients experienced fractures than did patients in the control group, we could not confirm differences in microarchitectural parameters using high-resolution peripheral quantitative CT. Therefore, it seems that bone geometry and microstructural parameters are not likely the cause of the increased proportion of fractures observed in our patients who were treated for osteosarcoma. Until we learn more about the bone changes associated with chemotherapy in patients with osteosarcoma, we recommend that patients undergo regular BMD testing, and we recommend that physicians consider osteoporosis treatment in patients with low BMD. These data might provide the impetus for future multicenter prospective studies examining the association between chemotherapy and bone microarchitecture. LEVEL OF EVIDENCE: Level III, therapeutic study.

How Common Are Chronic Residual Limb Pain, Phantom Pain, and Back Pain More Than 20 Years After Lower Limb Amputation for Malignant Tumors?

BACKGROUND: After major lower limb amputation, persistent pain is common, with up to 85% of patients reporting recurring phantom or residual-limb pain. Although pain management is an important factor of quality of life in patients with lower limb amputations, there are few long-term data regarding the frequency of persistent pain and how it impacts prosthesis use. QUESTIONS/PURPOSES: (1) How prevalent are different types of pain at long-term follow-up after amputation for malignant tumors? (2) What association do different pain types have with daily prosthesis use? METHODS: Between 1961 and 1995, 124 major amputations for malignant tumors were performed at one center in Austria in patients (1) who spoke German and (2) whose surgical date resulted in the possibility of a minimum follow-up time of 20 years at the time of this survey; those patients were considered potentially eligible for this retrospective study. The indications for major amputation were to achieve local tumor control in limbs that the surgeon deemed unsalvageable without amputation. Of those 124 patients, 71% (88) had died, 9% (11) could not be reached, and 3% (4) declined to participate. Thus, 58% (21 of 36) of those living at the time of this study and who underwent lower limb amputation between 1961 and 1993 with a median (range) follow-up duration of 41 years (23 to 55) completed a standardized questionnaire, including an assessment of pain and daily prosthesis use during the year before the survey. Phantom pain, residual limb pain, and back pain were each further subclassified into pain frequency, intensity, and restrictions in activities of daily living (ADL) due to the specific pain form and rated on a 5- (pain frequency) and 10-point (pain intensity, restrictions in ADL) numerical rating scale. Before multivariate regression analysis, daily prosthesis use was correlated with pain parameters using Spearman correlation testing. RESULTS: Seventeen of 21 patients reported phantom limb and back pain, and 15 patients reported residual limb pain in the past year. Median (range) phantom pain intensity was 7 (1 to 10) points, median residual limb pain intensity was 4 (1 to 9) points, and median back pain intensity was 5 (1 to 10) points. After controlling for relevant confounding variables such as age at amputation, age at survey, and stump length, we found that less intense residual limb pain (defined on a 10-point scale with 1 representing no pain at all and 10 representing extremely strong pain [95% CI 0.3 to 1.0]; r = 0.8; p = 0.003) was associated with greater daily prosthesis use. Higher amputation levels showed a decreased daily prosthesis use compared with patients with lower amputation levels (defined as transfemoral amputation versus knee disarticulation versus transtibial amputation [95% CI 0.3 to 5.1]; r = 0.5; p = 0.03). CONCLUSION: Decades after surgery, many patients with lower limb amputations experience pain that restricts them in terms of ADLs and decreases their daily prosthesis use. This information supports the need for regular residual limb inspections and careful prosthesis fitting even at long-term follow-up, as effective prosthesis fitting is a modifiable cause of residual limb pain. Future studies evaluating long-term treatment effects of pain relief surgery and therapeutic alternatives to conservative pain treatments should be performed, as these approaches may help alleviate pain in patients with refractory postamputation pain. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Thermal Effects during Bone Preparation and Insertion of Osseointegrated Transfemoral Implants.

BACKGROUND: The preparation of bone for the insertion of an osseointegrated transfemoral implant and the insertion process are performed at very low speeds in order to avoid thermal damages to bone tissue which may potentially jeopardize implant stability. The aim of this study was to quantify the temperature increase in the femur at different sites and insertion depths, relative to the final implant position during the stepwise implantation procedure. METHODS: The procedure for installation of the osseointegrated implant was performed on 24 femoral specimens. In one specimen of each pair, the surgery was performed at the clinically practiced speed, while the speed was doubled in the contralateral specimen. Six 0.075 mm K fine gauge thermocouples (RS Components, Sorby, UK) were inserted into the specimen at a distance of 0.5 mm from the final implant surface, and six were inserted at a distance of 1.0 mm. RESULTS: Drilling caused a temperature increase of <2.5 °C and was not statistically significantly different for most drill sizes (0.002 < p < 0.845). The mean increase in temperature during thread tapping and implant insertion was <5.0 °C, whereas the speed had an effect on the temperature increase during thread tapping. CONCLUSIONS: Drilling is the most time-consuming part of the surgery. Doubling the clinically practiced speed did not generate more heat during this step, suggesting the speed and thus the time- and cost-effectiveness of the procedure could be increased. The frequent withdrawal of the instruments and removal of the bone chips is beneficial to prevent temperature peaks, especially during thread tapping.

Distal femoral varus osteotomy: results of the lateral open-wedge technique without bone grafting.

BACKGROUND: The lateral opening wedge distal femoral osteotomy (LOWDFO) to reconstruct knee alignment in patients with genu valgum originating in the distal femur has gained importance within the last years. PURPOSE: To analyze clinical and radiographic outcome of patients treated with LOWDFO with respect to bone healing without grafting and patient age. MATERIAL AND METHODS: Twenty-two consecutive patients with genu valgum corrected with 23 LOWDFOs using a Tomofix-locking plate were retrospectively analyzed (mean age 23.7 years). Clinical evaluation was based on pre- and post-operative KOOS scores. A pre- and post-operative radiographic assessment, including MAD, mLDFA, LLD, bone healing, and patella parameters, was performed. Differences between subgroups (age, bone grafting) were analyzed. RESULTS: The restoration of MAD and mLDFA resulted in significantly improved post-operative KOOS5 scores in younger and older patients (p = 0.001). Bone healing without bone grafting was reliable in all patients. The leg length was significantly increased post-operatively (p = 0.001). The Blackburne-Peel ratio was significantly reduced to more normal values post-operatively (p < 0.001). CONCLUSION: LOWDFO without bone grafting is a reliable procedure representing a promising treatment option particularly in young patients with genu valgum. Besides correction of the MAD, a significant leg length increase and additional patella stability can be expected.

Projected numbers of primary total knee replacement in Austria from 2015-2075.

BACKGROUND: In 2012 and 2013 Austria had the highest rate of primary total knee replacements (TKR) amongst all European countries. This study was carried out to project the numbers of TKR and its associated costs in Austria into the year 2075. METHODS: Demographic data and population projections between 2011-2075 were obtained from European and Austrian authorities. Information about the present incidence of primary TKRs was obtained from the Austrian Prosthesis Register. Current TKR associated costs were obtained from federal healthcare insurances as well as federal and state admission agencies. Projections were stratified by age and gender and given for the lower, most likely and upper scenarios. RESULTS: Overall cost for the group of patients with primary TKR will increase by 50% for males and 32% for females by 2075. This increase is primarily driven by the increase in the population of men aged 80-90 years and 90+ years leading to an increase of 190% and 567% of the TKR associated costs. In comparison, women in these age groups are estimated to have an increase in TKR costs by 108% and 243%. CONCLUSION: These numbers represent a substantial socioeconomic burden to the Austrian society in the near and distant future due to the upcoming demographic changes. The presented results have their limitation in the unpredictable nature of assumptions but might guide Austrian and other European authorities in their efforts to provide more cost-effective and more directed care for patients in need of primary TKR surgery.

A comparative study of intraoperative frozen section and alpha defensin lateral flow test in the diagnosis of periprosthetic joint infection.

Background and purpose - For decision-making (aseptic vs. septic), surgeons rely on intraoperatively available tests when a periprosthetic joint infection (PJI) cannot be confirmed or excluded preoperatively. We compared and evaluated the intraoperative performances of the frozen section and the alpha defensin lateral flow test in the diagnosis of PJI. Patients and methods - In this prospective study, consecutive patients with indicated revision surgery after arthroplasty were included. Patients were classified as having PJI using the MusculoSkeletal Infection criteria. The presence of alpha defensin was determined using the lateral flow test intraoperatively. During revision surgery, tissue samples were harvested for frozen and permanent section. Analysis of diagnostic accuracy was based on receiver-operating characteristics. Results - 101 patients (53 hips, 48 knees) were eligible for inclusion. Postoperatively, 29/101 patients were diagnosed with PJI, of which 8/29 cases were definitely classified as septic preoperatively. Of the remainder 21 septic cases, the intraoperative alpha defensin test and frozen section were positive in 13 and 17 patients, respectively. Sensitivities of the alpha defensin test and frozen section were 69% and 86%, respectively. The area under the curves of both tests showed a statistically significant difference (p = 0.006). Interpretation - The frozen section showed a significantly higher performance compared with the alpha defensin test and a near perfect concordance with the definitive histology, and therefore remains an appropriate intraoperative screening test in diagnosing PJI. Although the sensitivity of the alpha defensin test was lower compared with that of frozen section, this test is highly specific for confirming the diagnosis of PJI.

What Sport Activity Levels Are Achieved in Patients After Resection and Endoprosthetic Reconstruction for a Proximal Femur Bone Sarcoma?

BACKGROUND: Limited information is available about sports activities of survivors after resection and reconstruction of primary malignant bone tumors with megaprostheses. Because patients often ask what activities are possible after treatment, objective knowledge about sports activities is needed to help assess the risks of sports participation and to help guide patients' expectations. QUESTIONS/PURPOSES: The aims of this study were to evaluate (1) what proportion of patients with proximal-femoral megaprostheses placed as part of tumor reconstructions can perform sports; (2) what activity levels they achieved; and (3) whether sports activity levels are associated with an increased likelihood of revision. METHODS: This retrospective study considered all 27 living patients in our institutional tumor registry with enduring proximal-femoral reconstructions performed more than 5 years ago who were between the ages of 11 and 49 years at the time of the reconstruction; seven were lost to followup and one was excluded because of paraplegia as a result of a car accident and another because of senile dementia; another two were excluded from statistics because of growing prostheses and skeletal immaturity at the time of followup, leaving 16 (11 male, five female) for analysis. Their mean age was 26 ± 12 years (range, 11-49 years) at surgery, and the mean followup was 18 ± 7 years (range, 5-27 years). Types of sports, frequency per week, duration of each sports session as well as the UCLA and modified Weighted Activity Score were assessed retrospectively by an independent assessor a median of 18 years (range, 5.3-27 years) after surgery. RESULTS: Patients recalled that preoperatively 14 were practicing sports 5 (± 4) hours/week. At followup, 11 of the patients were practicing one or more sports activities 2 (± 3) hours/week on a regular basis. The preoperative UCLA and modified Weighted Activity Score levels of 9 and 6 fell to levels of 6 (p = 0.005) and 3 (p = 0.025), respectively, at followup. With the numbers of patients available for study, we could not determine that prosthetic failures were associated with sport activity levels. CONCLUSIONS: Patients who survive primary malignant bone tumors in the proximal femur reconstructed by megaprostheses are able to perform some sports activities. The estimates of activity levels made in this study probably are best-case estimates, given that some patients were lost to followup; patients unaccounted for might not be doing as well as those represented here. Also, the degree to which sports participation influences implant durability remains, for the most part, unanswered; studies with more patients and longer followup will be needed to determine to what degree prosthesis survivorship relates to sporting activity levels. Most patients perform low-impact sports and at a lower level than they had preoperatively. Because this is a preliminary study of a select group of patients, further information is necessary to weight the benefits of higher sports activity levels against potential risks. If this can be confirmed in a larger number of patients, the information may guide surgeons in their discussion with patients preoperatively and give them some objective assessment of what to expect regarding sports activities. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Outcome of Total Hip and Total Knee Revision Arthroplasty With Minor Infection Criteria: A Retrospective Matched-Pair Analysis.

BACKGROUND: Although diagnostic modalities for the detection of periprosthetic joint infection have improved, some infectious revision cases may still be diagnosed as aseptic complications. We raised the question whether patients with positive Musculoskeletal Infection Society minor infection criteria differ in their outcome parameters (revision-free survival, revision rate) when compared to patients with "true" aseptic complications. Additionally, we asked whether the indication for revision surgery (eg, loosening) might have an influence on possible outcome discrepancies. METHODS: A retrospective matched-pair analysis was performed with 98 patients who had undergone revision surgery after total joint arthroplasty. Forty-nine patients showed less than 3 positive minor criteria (PMC), whereas 49 patients without any PMC were compared regarding re-revision rate and revision-free survival. Reasons for revisions were categorized according to loosening, liner wear, implant failure, and soft-tissue complication. RESULTS: In the group of patients with PMC, 30.6% (n = 15) had to undergo re-revision compared to 6.12% (n = 3) in the true aseptic complication control group. The long-term implant survival in the PMC group was 69.4% (95% confidence interval [CI], 47-69 months) and in the aseptic control group was 93.9% (95% CI, 82-94 months; P = .001). In patients with PMC and loosening of the implant, the long-term survival was 55.2% (95% CI survival time, 28.9-53.2 months) whereas in patients without PMC and loosening, the overall survival was 96.2% (95% CI survival time, 83.5-96 months; P = .001). CONCLUSION: Our findings suggest that in the presence of prosthetic loosening, even a single positive minor criterion may have a negative impact on the outcome after total hip arthroplasty and total knee arthroplasty revision surgeries.

Do Patients After Chondrosarcoma Treatment Have Age-appropriate Bone Mineral Density in the Long Term?

BACKGROUND: In long-term survivors of osteosarcoma and Ewing sarcoma treated with the addition of radio- and chemotherapy, low bone mineral density (BMD) and fractures have been observed, presumably resulting from these adjuvants. Because patients with chondrosarcoma usually are not treated with conventional adjuvant treatment, observation of low BMD in patients with chondrosarcoma presumably would be the result of other mechanisms. However, BMD in patients with a history of chondrosarcoma has not been well characterized. QUESTIONS/PURPOSES: The aim of our study was to address the following questions: (1) Do long-term survivors of chondrosarcoma have normal BMD and, if not, which factors contribute to low BMD? (2) Is there a greater risk of fracture and does the Fracture Risk Assessment Tool (FRAX(®)) score reflect fracture likelihood? METHODS: All known patients with a history of chondrosarcoma treated at our institution before 2006 were identified. Of 127 patients believed to be alive at the time of this study, 30 agreed to participate in this study (11 females, 19 males; mean age at surgery, 39 ± 12 years; mean followup, 12 ± 5 years). With the data available, the 30 participants were not different from the 97 nonparticipants in terms of age, sex, BMI, tumor grade, tumor location (axial versus appendicular, lower extremity versus elsewhere), and use of any treatment known to influence osteopenia (chemotherapy, lower extremity surgery). BMD was measured and history of fractures was assessed using a questionnaire. The patients´ BMD measurements in this study were sex- and age-matched with a normative sex- and age-categorized reference population reported by Kudlacek et al. Associations were tested by univariate regressions and ANOVAs of all measures of BMD and eligible oncologic and demographic factors. RESULTS: Eighteen of 30 (60%) patients had a pathologic BMD according to the WHO dual-energy x-ray absorptiometry definition, 15 (50%) had osteopenia, and three (10%) had osteoporosis. T-scores in the study cohort were lower than reference values for the femur neck (mean difference, 0.64; 95% CI, 0.27-1.01; p < 0.0015), but not for the spine (mean difference, 0.39; 95% CI, -0.06 to 0.84; p = 0.09). Thirteen patients (45%) reported a history of fractures not distinguishing between low and high impact. The incidence of fractures was 2.8 greater than expected from a comparison with a published microcensus survey of the Austrian population. No effect of the FRAX(®) score on fracture risk could be identified (p = 0.057). CONCLUSIONS: Long-term survivors of chondrosarcoma appear to be at greater risk for having low BMD develop than the healthy population. Although these results are preliminary and based on a very small sampling of patients, if they can be confirmed in larger studies, BMD assessment by dual-energy x-ray absorptiometry might be considered as these patients are followed posttreatment by sarcoma care units. The reasons for low BMD still must be elucidated. LEVEL OF EVIDENCE: Level IV, prognostic study.

C-reactive protein as a prognostic factor in patients with chordoma of lumbar spine and sacrum--a single center pilot study.

STUDY DESIGN: This is a retrospective, diagnostic study, level IV. BACKGROUND: It appears to be necessary to identify prognostic markers for individual risk estimation for progression and survival in patients with chordoma, a rare disease. Are pre-operative serum levels of C-reactive protein (CRP) associated with disease progression and survival? METHODS: Survival rates of 24 patients (18 males, 6 females) (mean age 67 years (SD ± 16; range 20-85 years); minimum follow-up 2 years, mean follow-up 5 years (SD ± 5; range 2-19 years)) with chordoma of the lower spine and sacrum were assessed with a focus on pre-operative CRP levels. RESULTS: The survival rate of patients with pre-operative CRP level of >1.0 mg/dl was lower than that of patients with a CRP level <1.0 mg/dl (p = 0.01). The estimated 10-year survival of patients with pre-operative CRP values <1.0 and >1.0 mg/dl was 76 and 25%, respectively. CRP remained as an independent survival factor (p = 0.025; CI 95% 1.0-2.6) in multivariable analysis. CONCLUSIONS: Pre-operative CRP levels appear to be a biomarker for disease-specific survival in patients with chordoma of the lumbar spine and sacrum. A validation of our finding with larger cohorts and integration of putative risk factor would further elucidate CRP a surrogate for tumor progression.

Low incidence of early developmental dysplasia of the hip in universal ultrasonographic screening of newborns: analysis and evaluation of risk factors.

PURPOSE: Different timing and approaches to screening for developmental dysplasia of the hip (DDH) are used in the orthopaedic community. Thus ultrasonographic screening programs and reports based on clinical examinations produced differing incidence rates of DDH. Furthermore different risk factors and a change of incidence of DDH in the last decades were discussed. The purpose of this study was the evaluation of incidence and risk factors of the very early DDH in a modern cohort based on a universal ultrasound screening program. METHODS: We analysed the results of the screening program performed at our institution: 5,356 consecutive hips of newborns were screened ultrasonographically and clinically according to the system published by R. Graf within the first two postnatal weeks [1]. A set of risk factors was analysed by univariate and multiple linear regression models. RESULTS: Sonographic signs of developmental dysplasia of the hip were found in 0.24 % of the newborns. A significant negative influence of the risk factors birth weight, family history of DDH and female gender on the α-angle was found. Early or pre-term delivery showed a protective potential for DDH. CONCLUSIONS: Our data show a very low incidence of DDH in the first two postnatal weeks. Despite the significance of the risk factors analysed, it has to be considered that these factors only showed low impact on the risk of early DDH. In conclusion we favour universal ultrasound screening for DDH at the age of six to eight weeks.

Do patients with ewing's sarcoma continue with sports activities after limb salvage surgery of the lower extremity?

BACKGROUND: Limb salvage surgery has evolved to become the standard method of treating sarcomas of the extremities with acceptable oncologic results. However, little information exists relative to the activity level or ability to participate in sports after tumor reconstructions. QUESTIONS/PURPOSES: The aims of the study were to answer the following questions: (1) Which sports activity levels and what types of sports can be expected in the long term after tumor reconstruction? (2) Which frequency durations are patients with Ewing's sarcoma able to perform in long-term followup after local control? (3) Do surgical complications affect sports activity level? METHODS: Thirty patients (13 females, 17 males; mean age, 18 ± 8 years; range, 2-36 years at diagnosis; mean followup 16 ± 6 years [minimum, 5 years]) were included. Tumors were located in the pelvis, femur, tibia, and fibula. Surgical procedures included surgical resections alone (n = 8), surgical resection with biological reconstruction (n = 9), or endoprosthetic reconstruction (n = 13). We assessed UCLA sports activity levels, kinds of sports as well as the frequency per week and the duration of each training unit at long term (minimum followup, 5 years). RESULTS: In long-term followup 83% patients (25 of 30) were performing athletic activity regularly. The hours/week of sports depended on type of surgery and were highest after resections in the pelvis and femur (5.8) and were lowest after megaprosthetic reconstruction of the pelvis (1.0). Patients undergoing biologic reconstructions were able to perform high-impact sports. UCLA sports activity levels were high after joint-preserving vascularized fibula for tibia reconstruction (7.4) and after megaprosthetic reconstruction of the lower extremity (6.3-6.4) and were low after tumors located in the fibula (4.2). Complications during followup did not significantly influence sports activity in long-term survivors. CONCLUSIONS: Long-term survivors can achieve high levels of sports activity in many instances. Tumor sites are associated with the postoperative sports activity levels. This information can help surgeons counsel patients in terms of athletic expectations after limb salvage reconstruction for patients with Ewing's sarcoma. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

What sports activity levels are achieved in patients with modular tumor endoprostheses of osteosarcoma about the knee?

BACKGROUND: Advances in multimodal treatment have improved survival of patients with nonmetastatic osteosarcoma. At the same time, implant design has improved the outcomes of limb salvage with modular endoprostheses. However, little is known about sports activity in long-term survivors with osteosarcoma. QUESTIONS/PURPOSES: We wanted to evaluate (1) sports activity levels in long-term survivors of osteosarcoma about the knee who received a modular tumor endoprosthesis; (2) to determine if activity level changed over time from initial reconstruction or (3) was predicted from sports activity level before diagnosis; and (4) if complications that occurred affected sports or contributed to prosthetic failures. METHODS: Between 1995 and 2005, we treated 120 patients for osteosarcoma about the knee with resection and modular endoprosthetic reconstruction; of those, 25 (21%) have died, six (5%) had an amputation, 39 (32%) did not speak German and so were ineligible, and 14 (12%) were either lost to followup or refused to participate, leaving 27 patients (14 females, 13 males; median age 19 years [range, 12-60 years); average followup 11 ± 4 years) (54% of the living, German-speaking cohort) for this analysis. Tumors were located in the distal femur (n = 16) and the proximal tibia (n = 11). Sports participation as well as the UCLA Activity Score and the modified Weighted Activity Score were assessed retrospectively. Moreover, postoperative complications were evaluated. RESULTS: Before the diagnosis of osteosarcoma and 1, 3, and 5 years and at the latest followup, respectively, after their reconstructions, 24 (89%), nine (33%), 20 (74%), and 24 patients (89%) were able to perform sports activities. There was a reduction in high-impact activities. Those patients with followup longer than 5 years had no changes in sports activity at their latest followup. Patients who had higher levels of sports activity levels before surgery generally had higher levels of activity at last followup (UCLA Activity Score: r = 0.62, p < 0.0005; modified Weighted Activity Score r = 0.49, p < 0.01). Fourteen patients (51%) underwent revision surgery. With the numbers available, complications had no effect on sports activity. No sports activity-related complications were found. CONCLUSIONS: Some long-term survivors of osteosarcoma can achieve high levels of sports activity. Preoperative activity levels seem to influence the postoperative activity levels. This information is important to give realistic expectations for long-term survivors of osteosarcoma of the knee. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Human osteoarthritic knee cartilage: fingerprinting of adhesion/growth-regulatory galectins in vitro and in situ indicates differential upregulation in severe degeneration.

The apparent connection of galectin-3 to chondrocyte survival and osteoarthritis-like cartilage modifications in animal models provided incentive for the mapping of seven members of this family of adhesion/growth-regulatory proteins in human cartilage specimens. Starting with work in vitro, RT-qPCR analyses and immunocytochemistry revealed gene transcription and protein presence in cultured OA chondrocytes, especially for galectin-1, galectin-3 and galectin-8. Immunohistochemistry in clinical specimens with mild and severe cartilage degeneration detected galectins in chondrocytes-with upregulation, especially of galectin-1 in areas of severe degeneration-accompanied by α2,6-sialylation in the pericellular matrix. Given the possibility for additive/antagonistic activities between galectins, these results direct further research toward examining cellular effects of (1) these proteins (alone or in combination) on chondrocytes and (2) remodeling of the chondrocyte glycophenotype.

Do long term survivors of ewing family of tumors experience low bone mineral density and increased fracture risk?

BACKGROUND: Multimodal treatment regimens for Ewing's sarcoma have led to survival rates approaching 70% of patients with no metastases at diagnosis. However, these treatments have long-term side effects. Low bone mineral density (BMD) and risk of fractures can occur owing in part to chemotherapy and limited mobility from local control of the primary tumor. QUESTIONS/PURPOSES: We performed this study to answer the following questions: (1) Do long-term survivors of the Ewing family of tumors sustain low BMD? (2) Which factors are associated with BMD in these patients? (3) Do they experience fractures? (4) Are BMD and fractures associated with each other? METHODS: We queried our institutional registry to identify all known survivors of Ewing tumors who were treated before 2005. Of 100 such patients, 67 (67%) responded to a postal survey to participate in this study, and an additional 11 (11%) patients were excluded according to prespecified criteria. In the remaining 56 long-term survivors (27 females, 29 males; mean±SD age at followup, 32±10 years; mean followup, 15±7 years), BMD was measured by dual-energy x-ray absorptiometry and history of fractures was assessed using a questionnaire. Associations were tested using univariate and multivariate models by stepwise variable selection procedure, including Bonferroni correction. RESULTS: Thirty-one of 56 (56%) patients had a pathologic BMD. Seven (13%) had osteoporosis and 24 (43%) had osteopenia. Factors related to low BMD after Bonferroni correction were the length of time between surgery and followup and the BMI at followup. Twenty-one patients reported 29 fractures. With the numbers available, BMD levels were not associated with fractures. CONCLUSIONS: We could not confirm some potentially important predictors for fractures to be associated with clinical events of interest. However, the data are valuable as hypothesis-generating pilot data for future, multicenter prospective studies. If BMD changes cannot explain the propensity of fractures, there may be other bone characteristics like microarchitectural changes of bone to more accurately explain the effect. LEVEL OF EVIDENCE: Level IV, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.

Dimensional accuracy and precision and surgeon perception of additively manufactured bone models: effect of manufacturing technology and part orientation.

BACKGROUND: Additively manufactured (AM) anatomical bone models are primarily utilized for training and preoperative planning purposes. As such, they must meet stringent requirements, with dimensional accuracy being of utmost importance. This study aimed to evaluate the precision and accuracy of anatomical bone models manufactured using three different AM technologies: digital light processing (DLP), fused deposition modeling (FDM), and PolyJetting (PJ), built in three different part orientations. Additionally, the study sought to assess surgeons' perceptions of how well these models mimic real bones in simulated osteosynthesis. METHODS: Computer-aided design (CAD) models of six human radii were generated from computed tomography (CT) imaging data. Anatomical models were then manufactured using the three aforementioned technologies and in three different part orientations. The surfaces of all models were 3D-scanned and compared with the original CAD models. Furthermore, an anatomical model of a proximal femur including a metastatic lesion was manufactured using the three technologies, followed by (mock) osteosynthesis performed by six surgeons on each type of model. The surgeons' perceptions of the quality and haptic properties of each model were assessed using a questionnaire. RESULTS: The mean dimensional deviations from the original CAD model ranged between 0.00 and 0.13 mm with maximal inaccuracies < 1 mm for all models. In surgical simulation, PJ models achieved the highest total score on a 5-point Likert scale ranging from 1 to 5 (with 1 and 5 representing the lowest and highest level of agreement, respectively), (3.74 ± 0.99) in the surgeons' perception assessment, followed by DLP (3.41 ± 0.99) and FDM (2.43 ± 1.02). Notably, FDM was perceived as unsuitable for surgical simulation, as the material melted during drilling and sawing. CONCLUSIONS: In conclusion, the choice of technology and part orientation significantly influenced the accuracy and precision of additively manufactured bone models. However, all anatomical models showed satisfying accuracies and precisions, independent of the AM technology or part orientation. The anatomical and functional performance of FDM models was rated by surgeons as poor.

Long-term functional and clinical outcome of combined targeted muscle reinnervation and osseointegration for functional bionic reconstruction in transhumeral amputees: a case series.

OBJECTIVE: To describe and evaluate the combination of osseointegration and nerve transfers in 3 transhumeral amputees. DESIGN: Case series. PATIENTS: Three male patients with a unilateral traumatic transhumeral amputation. METHODS: Patients received a combination of osseointegration and targeted muscle reinnervation surgery. Rehabilitation included graded weight training, range of motion exercises, biofeedback, table-top prosthesis training, and controlling the actual device. The impairment in daily life, health-related quality of life, and pain before and after the intervention was evaluated in these patients. Their shoulder range of motion, prosthesis embodiment, and function were documented at a 2- to 5-year follow-up. RESULTS: All 3 patients attended rehabilitation and used their myoelectric prosthesis on a daily basis. Two patients had full shoulder range of motion with the prosthesis, while the other patient had 55° of abduction and 45° of anteversion. They became more independent in their daily life activities after the intervention and incorporated their prosthesis into their body scheme to a high extent. CONCLUSION: These results indicate that patients can benefit from the combined procedure. However, the patients' perspective, risks of the surgical procedures, and the relatively long rehabilitation procedure need to be incorporated in the decision-making.