Magnetic Stimulus Responsive DDS Based on Chitosan Microbeads Embedded with Magnetic Nanoparticles

In this paper, we have presented a novel Drug Delivery Substrate (DDS) that that is responsive to external stimuli of high-frequency alternating magnetic fields. The DDS is constituted of chitosan crosslinked with PEGDMA (polyethylene glycol dimethacrylate), loaded with Fe₃O₄ magnetic nanoparticles and vancomycin. In another experiment, a 19-hour elution was observed where three magnetic stimuli of 25 mT, 109.9 kHz were given for 60 min to the test samples. The stimuli were separated by several hours. After excitation span, it was observed that the stimulated samples released a significantly higher amount of vancomycin by as much as 21% compared to non-stimulated samples. In another study, preliminary results showing the effect of different PEGDMA chain lengths have been discussed. These results show evidence of a smart, controllable DDS that allows modulation of its normal passive antibiotic elution by applying external stimuli per personalized needs.

Extendable Endoprostheses in Skeletally Immature Patients: A Study of 124 Children Surviving More Than 10 Years After Resection of Bone Sarcomas

BACKGROUND

Extendable endoprostheses are used to reconstruct segmental defects following resection of bone sarcomas in skeletally immature patients. However, there remains a paucity of studies with regard to long-term outcomes.

METHODS

We retrospectively reviewed 124 skeletally immature children who underwent an extendable endoprosthetic replacement and survived more than 10 years after the surgical procedures. Anatomical sites included the distal part of the femur (n = 66), the proximal part of the femur (n = 13), the proximal part of the tibia (n = 29), and the proximal part of the humerus (n = 16). Complications and implant survival were classified according to the modified Henderson criteria.

RESULTS

The mean follow-up was 24 years (range, 10 to 36 years). The mean age at the time of the extendable endoprosthetic replacement was 9 years (range, 2 to 16 years). All patients had reached skeletal maturity at the last follow-up. The 10-year endoprosthetic failure-free survival rate was 28%. A total of 243 complications occurred in 90% of patients; these complications were most frequently related to soft-tissue problems (27% of complications). The incidence of and cumulative survival with respect to each failure mode varied between anatomical sites. Soft-tissue failures occurred most frequently in the proximal part of the femur (77%; p = 0.003), and the distal part of the femur was the most frequent site of aseptic loosening (52%; p = 0.014) and structural failure (55%; p = 0.001). Excluding lengthening procedures, 105 patients (85%) underwent an additional surgical procedure, with a mean of 2.7 surgical procedures per patient (range, 0 to 7 surgical procedures per patient). The mean limb-length discrepancy at the final follow-up was 1 cm (range, 0 to 9 cm). Limb salvage was achieved in 113 patients (91%). The mean Musculoskeletal Tumor Society functional score (the percentage of a total score of 30 points) was 82% (range, 40% to 100%) in 115 patients with available data at the last follow-up.

CONCLUSIONS

Extendable endoprostheses are associated with a high complication rate and a need for additional surgical procedures over time. Despite this, successful limb salvage with reasonable function and small limb-length discrepancy is achievable in the long term. Our study provides benchmark data for individual anatomical sites for further improvements of outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Extra-articular resection of shoulder joint for bone sarcomas: Oncologic and limb-salvage outcomes of 32 cases compared with shoulder disarticulation and forequarter amputation

BACKGROUND AND OBJECTIVES

We aimed to identify the overall survival (OS), surgical complications, survival of reconstruction, and functional outcome of patients who underwent extra-articular resection of the shoulder joint for primary bone sarcomas. The OS and local recurrence rates in patients who underwent an amputation were also evaluated for comparison.

METHODS

Thirty-two patients treated between 1988 and 2017 were studied. The tumours were located in the humerus in 22 (69%) and scapula in 10 patients (31%). The resection types were Malawer type IV in 6 (19%), type V in 21 (66%), and type VI in 5 patients (15%). Reconstruction was performed with endoprosthesis in 23 patients (72%) while excision arthroplasty with the suspension of the humerus to the clavicle was performed in 9 patients (28%). Surgical margins were wide in 16, marginal in 8, intralesional in 3, and not available in 5 patients. During the study period, 40 patients underwent a forequarter amputation and 11 patients underwent a shoulder disarticulation.

RESULTS

The 5-year OS for patients who underwent extra-articular resection of the shoulder joint was 42% which was not statistically different compared with that of patients who underwent amputation (5-year OS = 30%; P = .091). The 5-year survival of the reconstruction was 94%, similar for endoprosthesis and excision arthroplasty. Local recurrence and complications developed in 6 (19%) and 10 patients (31%), respectively. Failures of the reconstruction requiring revision surgery occurred in two patients (6%). Limb salvage was achieved in 30 patients (94%). The median Musculoskeletal Tumour Society functional score was 61% (interquartile range, 57%-70%) and was similar in the endoprosthesis and excision arthroplasty group.

CONCLUSIONS

Extra-articular resection of the shoulder joint for bone sarcomas is an effective limb-salvage method. However, local recurrence remains a principal concern.

The long-term results of extendable endoprostheses of the humerus in children after the resection of a bone sarcoma

Aims

The purpose of this study was to report the long-term results of extendable endoprostheses of the humerus in children after the resection of a bone sarcoma.

Methods

A total of 35 consecutive patients treated with extendable endoprosthetic replacement of the humerus in children were included. There were 17 boys and 18 girls in the series with a median age at the time of initial surgery of nine years (interquartile range (IQR) 7 to 11).

Results

The median follow-up time was 10.6 years (IQR 3.9 to 20.4). The overall implant survival at ten years was 75%. Complications occurred in 13 patients (37%). Subluxation at the proximal humerus occurred in 19 patients (54%) but only six (17%) were symptomatic. Subluxation was seen more commonly in children under the age of nine years (86%) than in those aged nine years or more (33%) (p = 0.002). Implant failure occurred in nine patients (26%): the most common cause was aseptic loosening (four patients, 11%). Lengthening of the implant was carried out in 23 patients (66%). At final follow up, three patients had a limb that was shortened by 5 cm or more. The mean Musculoskeletal Tumor Society (MSTS) functional score was 79% (73% to 90%).

Conclusion

Extendable endoprosthetic replacement is a reliable method of reconstructing humerus after excision of a bone sarcoma. Children who are less than nine years old have a high risk of subluxation. Cite this article: Bone Joint J 2020;102-B(1):64–71

Sacral chordoma: do the width of surgical margin and the use of photon/proton radiotherapy affect local disease control?

PURPOSE

Chordoma is a rare but highly aggressive primary bone sarcoma that arises commonly from the sacrum. While en bloc resection has been the mainstay of the treatment, the role of resection margin in millimetres with/without adjuvant radiotherapy (RT) has been unknown. We investigated the prognostic impact of surgical margin width, adjuvant RT, and their combined factor for sacral chordoma.

METHODS

Forty-eight patients who underwent surgical treatment between 1996 and 2016 were studied. Of these, 11 patients (23%) received adjuvant RT; photon RT in 7 (15%) and proton RT in 4 (8%). Margins were microscopically measured in millimetres from the resection surface to the closest tumour on histologic slides.

RESULTS

The five year and ten year disease-specific survival was 88% and 58%, respectively, and the local recurrence (LR) rate was 48%. The LR rate with 0-mm, < 1.5-mm, and ≥ 1.5-mm margin was 50% (group 1), 50% (group 2: RT-, 61%; group 3: RT+, 14%), and 0% (group 4), respectively. We observed a significantly lower LR rate in patients with adjuvant photon/proton RT (18%) than without it (57%; p = 0.026), and no LR was observed after post-operative proton RT. The combined factor of margin with RT clearly stratified the LR risk: patients of group 1 (positive margin) and 2 (< 1.5-mm margin, RT-) had approximately 7.5× LR risk (p = 0.049) compared with those of group 3 (< 1.5-mm margin, RT+) and 4 (≥ 1.5-mm margin).

CONCLUSION

This study identified the lowest risk of local failure in tumour resection with ≥ 1.5-mm margin or negative but < 1.5-mm margin with the use of adjuvant photon/proton radiotherapy for sacral chordoma. Early results of adjuvant proton RT demonstrated excellent local control.

The long-term outcomes of modified Harrington procedure using antegrade pins for periacetabular metastasis and haematological diseases

AIMS

The aim of this study was to present the long-term surgical outcomes, complications, implant survival, and causes of implant failure in patients treated with the modified Harrington procedure using antegrade large diameter pins.

PATIENTS AND METHODS

A cohort of 50 consecutive patients who underwent the modified Harrington procedure for periacetabular metastasis or haematological malignancy between January 1996 and April 2018 were studied. The median follow-up time for all survivors was 3.2 years (interquartile range 0.9 to 7.6 years).

RESULTS

The five-year overall survival rate was 33% for all the patients. However, implant survival rates were 100% and 46% at five and ten years, respectively. Eight patients survived beyond five years. There was no immediate perioperative mortality or complications. A total of 15 late complications occurred in 11 patients (22%). Five patients (10%) required further surgery to treat complications. The most frequent complication was pin breakage without evidence of acetabular loosening (6%). Two patients (4%) underwent revision for aseptic loosening at 6.5 and 8.9 years after surgery. Ambulatory status and pain level were improved in 83% and 89%, respectively.

CONCLUSION

The modified Harrington procedure for acetabular destruction has low complication rates, good functional outcome, and improved pain relief in selected patients Cite this article: Bone Joint J 2019;101-B:1557-1562.

Surgical outcomes and prognostic factors of non-metastatic radiation-induced sarcoma of bone

BACKGROUND

The survival and prognostic factors in non-metastatic, radiation-induced bone sarcomas of bone have not been described. Moreover, the quantitative data about surgical outcomes and complications after limb-salvage surgery versus amputation are quite limited.

METHODS

Twenty-five patients with non-metastatic, radiation-induced sarcoma of bone who underwent definitive surgery were analysed. Histological diagnosis was osteosarcoma in 19 and undifferentiated pleomorphic sarcoma in six. The definitive surgery was limb-salvage surgery in 15 patients and an amputation in 10.

RESULTS

The 5-year overall survival rate (OS) and the 5-year event-free survival rate (EFS) were 53% (95% CI 31%-70%) and 40% (21%-59%), respectively. Patients with wide or radical surgical margins (n = 13) showed significantly better OS compared with those with marginal (n = 8) or intralesional (n = 2) margins (5-year OS, radical or wide = 74%, marginal = 17%, intralesional = 0%, p = 0.044). The risk of local recurrence was significantly higher in the limb-salvage group compared to the amputation group (49% vs 0%, p = 0.011). OS and EFS were not significantly different between limb-salvage group and an amputation group (p = 0.188 and 0.912, respectively).

CONCLUSIONS

We believe non-metastatic, radiation-induced sarcoma of bone should be resected with the aim of achieving wide or radical margins. Although limb-salvage surgery was related to higher rates of local recurrence compared with those of the amputation group, OS and EFS were not different among two groups. Surgeons need to discuss the higher risk of local recurrence in limb-salvage surgery.

Medical costs associated with childhood maltreatment history among Japanese older people

Background

Childhood maltreatment can have a significant impact on health across the life course, but its impact on health care costs in later life is unknown in Japan. This study aims to assess additional medical costs of Japanese older people with childhood maltreatment history.

Methods

Data from the Japan Gerontological Evaluation Study (JAGES) 2013, a population-based cohort of independent people aged 65 years or older across Japan were used and linked uniquely with the database of health insurance claims for residents of a city with more than 1.5 million citizens, aged 75 years or younger (N = 978). Average annual medical costs for April 2012 and March 2013 and April 2013 and March 2014 were calculated and compared between those who experienced childhood maltreatment and those who did not, using generalized linear models.

Results

4.5% of our sample witnessed their father physically abusing their mother, 1.9% were physically abused, 10.6% were emotionally neglected, and 5.7% were emotionally abused in their childhood. Average medical costs of those with any childhood maltreatment (N = 176, 18.0% of the sample) were significantly higher than those without maltreatment (549,468JPY vs. 413,013JPY (1USD is equivalent to 110JPY); p = 0.007). When examining the effect of each type of maltreatment, average costs of those with emotional neglect were higher than the counterpart (573,481JPY vs. 412,082JPY; p = 0.008). Average costs of those who experienced physical abuse were also higher than those who did not (726,254JPY vs 431,106JPY; p = 0.035). The effect of any childhood maltreatment remained statistically significant after older adults’ age and gender were controlled (p = 0.03).

Conclusions

Our findings suggest that childhood maltreatment is strongly associated with additional medical costs among older Japanese. If it was truly causal, it can be estimated that additional medical costs associated with childhood maltreatment can be more than 333 billion JPY per year nationwide.

Key messages

Average annual medical costs of older adults with any childhood maltreatment history were significantly 116,098 JPY greater than those with no maltreatment history. As for each type of childhood maltreatment, emotional neglect tends to increase medical costs in late adulthood.

The association between eating vegetables at start of meal and dental caries among Japanese children

Background

Dental caries is still serious problem among Japanese children. Previous studies suggested that higher consumption of vegetables prevent dental caries. Eating order habit, such as eating vegetables at start of meal, called “Vege-first”, may increase the amount of vegetable consumption, and in turn, prevent dental caries. However, no published studies have examined the impact of “Vege-first” habit on dental caries. The aim of this study to investigate the association between “Vege-first” and dental caries among Japanese children.

Methods

We used the 2015 cross-sectional data from the Adachi Child Health Impact of Living Difficulty (A-CHILD) study, a population-based study of all first-grade students in Adachi City, Tokyo, Japan. The number of DMFT (decayed, missed due to decay, and filled teeth) was used as an outcome. Poisson regression analyses were applied to determine the independent association between “Vege-first” habit and the number of DMFT after controlling for the effects from child’s sex, parents’ marital status, socioeconomic status, and frequency of tooth brushing, drinking sweet beverages, and snacking.

Results

Of 3,689 valid Japanese children participants, 38.2% had DMFT and 11.6% were having the “Vege-first” habit. The number of DMFT decreased linearly with “Vege-first” habit (p &lt; 0.001). After controlled for covariates, the number of DMFT was still significantly and independently decreased with “Vege-first” habit (prevalence ratio=0.89 (95% confidential interval [0.81-0.98])).

Conclusions

This study showed that having the “Vege-first” habit was associated with dental caries even accounting for socioeconomic status, dental health behavior, and dietary habits. Health policy introducing “Vege-first” habit may be effective to prevent pediatric dental caries.

Key messages

Eating habit which vegetables at start of meal called “Vege-first” may increase the amount of vegetable consumption and possibly reduce dental caries. The habituation of Vege-first was likely to reduce child’s dental caries even accounting for socioeconomic status, dental health behavior and dietary habits.

Combined effect of adverse childhood experiences and young age on self-harm ideation after birth

Background

Suicide among postpartum women is a new and emerging issue in developed countries. However, little is known about the combined effect of risk factors on self-harm ideation, although various risk factors have been found. The aim of this study is to examine the combined effect of maternal adverse childhood experiences and maternal age on self-harm ideation among postpartum women.

Methods

The study comprised a cross-sectional study of 8,074 mothers participating in a 3-month health checkup between September 2013 and August 2014 in City A, Prefecture A, Japan. Main outcome was self-harm ideation assessed using the Edinburgh Postnatal Depression Scale (EPDS), item 10. Possible risk factors were maternal adverse childhood experiences (ACEs), maternal characteristics, relationship with husband/partner (e.g., feelings when pregnancy was confirmed), household characteristics, child characteristics (e.g., age, sex, birth weight), and postpartum characteristics, and postpartum depression status other than self-harm ideation.

Results

Postpartum women with 3 or more ACEs and younger age (&lt;25 years old) were 10.3 times more likely than those with no ACEs and older age to have self-harm ideation (95%CI=5.3-20.2). This combined effect was also found in first-time mothers (OR = 7.6, 95%CI=3.2-17.9).

Conclusions

Postpartum women with 3 or more ACEs and who were younger than 25 years old were at a high risk for self-harm ideation. Providing prevention strategies aimed at mothers with multiple risk factors, especially younger age and ACEs, is warranted.

Key messages

Mothers with 3 or more ACEs and younger age had a high self-harm ideation risk. Providing prevention strategies for mothers with multiple risk factors is warranted.

Association of maternal developmental disorder traits with child maltreatment

Objective

Maternal mental disorders are known risk factors for child mistreatment. However, little is known about the involvement of maternal developmental disorder traits. The aim of this study was to examine maternal traits related to Pervasive Developmental Disorder (PDD) and Attention Deficit Hyperactivity Disorder (ADHD), and their possible association with child maltreatment.

Methods

Maternal PDD and ADHD were assessed through a self-administered questionnaire (N = 846) during mid-pregnancy using the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS) and Adult ADHD Self-Report Scale (ASRS). The mothers completed another questionnaire on child mistreatment when the offspring was approximately 18 months of age. The associations between maternal PDD and ADHD traits and child maltreatment score were analyzed using linear regression models adjusted for covariates.

Results

Mothers who exhibited stronger PDD traits showed significantly higher child maltreatment score, even after adjustment for maternal characteristics at baseline and ADHD traits. At the same time, ADHD traits were significantly associated with child maltreatment after adjustment of covariates, although the association became non-significant after adjustment of PDD traits.

Conclusions

Mothers who showed PDD and ADHD traits during pregnancy were more likely to maltreat their children. It is essential to educate mothers with such traits with appropriate, easy-to-follow childcare instructions, preferably in simple language combined with pictorial aids.

Key messages

Maternal developmental disorder traits are risk factor of child maltreatment. Specific parenting training intervention for mothers with developmental disorders are needed.

The Clinical Outcomes of Hemicortical Extracorporeal Irradiated Autologous Bone Graft After Tumor Resection of Bone and Soft Tissue Sarcoma

BACKGROUND/AIM

We analyzed the process of healing at osteotomy sites and timing of achievement of full weight-bearing in sarcoma patients who underwent hemicortical or intercalary reconstruction using the extracorporeal irradiated autologous bone graft technique.

PATIENTS AND METHODS

We studied 10 patients who had undergone tumor resection and reconstruction with hemicortical extracorporeal irradiated autologous bone graft at mid-shaft femur or tibia. The control group consisted of 30 patients who received the reconstruction using intercalary bone graft.

RESULTS

Full weight-bearing was achieved in all 10 patients at a median time of 4.8 months. Function was excellent in all patients. When comparing the clinical outcome among the patients who received intercalary and hemicortical grafts, the duration to full weight-bearing achievement in patients who received hemicortical graft was shorter than that in those with intercalary graft.

CONCLUSION

Early full weight-bearing may be achieved in patients undergoing hemicortical resection and reconstruction using extracorporeal irradiated autologous bone graft.

Secondary chondrosarcoma arising from osteochondroma: outcomes and prognostic factors

AIMS

The aim of this study was to report the outcomes of patients who underwent definitive surgery for secondary chondrosarcomas arising from osteochondromas.

PATIENTS AND METHODS

A total of 51 patients with secondary chondrosarcomas occurring from osteochondromas were reviewed. Median age was 36 years (interquartile range (IQR) 15 to 82). Median follow-up was 6.9 years (IQR 2.8 to 10.6). The pelvis was the most commonly affected site (59%). Histological grades were grade I in 35 (69%), grade II in 13 (25%), and grade III in three patients (6%).

RESULTS

Preoperative biopsy histology correctly predicted the final histological grade in 27% of patients. The ten-year disease-specific survival (DSS) for all patients was 89.4%. Local recurrence occurred in 15 patients (29%), more commonly in pelvic tumours (37%) compared with limb tumours (19%). Four patients with pelvic tumours died from progression of local recurrence. No patient with limb tumours died of disease. Wide/radical margin was associated with improved local recurrence-free survival (p = 0.032) and local recurrence was associated with worse DSS (p = 0.005).

CONCLUSION

We recommend that a secondary chondrosarcoma arising from osteochondroma of the pelvis is resected with wide/radical resection margins. The balance between the morbidity of surgery and risk of local recurrence needs to be considered in patients with limb secondary chondrosarcomas. Cite this article: Bone Joint J 2019;101-B:1313-1320.

P6209Relationship between skin autofluorescence levels and clinical outcomes in heart failure patients undergoing cardiac rehabilitation

Background

Advanced glycation end-products, indicated by skin autofluorescence (SAF) levels, could be prognostic predictors of all-cause and cardiovascular mortality in patients with diabetes mellitus (DM) and renal disease. However, the clinical usefulness of SAF levels in patients with heart failure (HF) who underwent cardiac rehabilitation (CR) remains unclear.

Purpose

The purpose of this study was to investigate the prognostic value of SAF levels in patients with HF who underwent CR.

Methods

This study enrolled 204 consecutive patients with HF who had undergone CR at our university hospital between November 2015 and October 2017. Clinical characteristics and anthropometric data were collected at the beginning of CR. SAF levels were noninvasively measured with an autofluorescence reader. The major adverse cardiovascular event (MACE) was a composite of all-cause mortality and unplanned hospitalization for HF. Follow-up data concerning primary endpoints were collected until November 2018.

Results

Patients' mean age was 68.1 years, and 61% were males. Patients were divided into two groups according to the median SAF levels (high and low SAF groups). Patients in the high SAF group were significantly older, had a higher prevalence of chronic kidney disease, and histories of coronary artery bypass surgery; however, there were no significant between-group differences in sex, prevalence of DM, left ventricular ejection fraction, and physical function. During a median follow-up period of 623 days, 25 patients experienced all-cause mortality and 34 were hospitalized for HF. Kaplan–Meier analysis showed that patients in the high SAF group had a higher incidence of MACE (log-rank P<0.05), whereas when patients were divided into two groups according to the median hemoglobin A1c level, no significant between-group difference was observed for the incidence of MACE (Figure). After adjusting for confounding factors, Cox regression multivariate analysis revealed that SAF levels were independently associated with the incidence of MACE (hazard ratio: 1.74, 95% confidence interval: 1.12–2.65, P<0.05).

Figure 1

Conclusion

SAF levels were significantly associated with the incidence of MACE in patients with HF and may be useful for risk stratification in patients with HF who undergo CR.

Physeal-preserving endoprosthetic replacement with short segment fixation in children with bone sarcomas

AIMS

The aim of this study was to report the results of custom-made endoprostheses with extracortical plates plus or minus a short, intramedullary stem aimed at preserving the physis after resection of bone sarcomas in children.

PATIENTS AND METHODS

Between 2007 and 2017, 18 children aged less than 16 years old who underwent resection of bone sarcomas, leaving ≤ 5 cm of bone from the physis, and reconstruction with a custom-made endoprosthesis were reviewed. Median follow-up was 67 months (interquartile range 45 to 91). The tumours were located in the femur in 11 patients, proximal humerus in six, and proximal tibia in one.

RESULTS

The five-year overall survival rate was 78%. No patient developed local recurrence. The five-year implant survival rate was 79%. In all, 11 patients (61%) developed a complication. Seven patients (39%) required further surgery to treat the complications. Implant failures occurred in three patients (17%) including one patient with aseptic loosening and two patients with implant or periprosthetic fracture. The preserved physis continued to grow at mean 3.3 cm (0 to 14). The mean Musculoskeletal Society score was 88% (67% to 97%).

CONCLUSION

Custom-made endoprostheses that aim to preserve the physis are a safe and effective option for preserving physeal growth, limb length, and joint function with an acceptable rate of complications. Cite this article: Bone Joint J 2019;101-B:1144-1150.

Surgical treatment for pelvic Ewing sarcoma: What is a safe and functional acetabular reconstruction when combined with modern multidisciplinary treatments?

PURPOSE

The purpose of this study was to clarify which local treatment is oncologically and functionally effective in pelvic Ewing sarcoma (ES).

METHODS

A consecutive series of patients who underwent pelvic resections and acetabular reconstructions after chemotherapy between 1986 and 2016 at a supra-regional center were evaluated.

RESULTS

The cohort consisted of 35 patients. The 5-year overall survival (OS) and local recurrence-free survival (LRFS) was 61% and 72%, respectively. Preoperative radiotherapy (RT) and surgery provided an excellent/good histological response in 92% and achieved significantly better OS (5 years, 64%) and LRFS (5 years, 100%) than surgery alone or surgery with postoperative RT. The Musculoskeletal Tumor Society functional scores were significantly better in patients with hip transposition than those with structural reconstructions (74% vs 57%; P = .031) using custom-made prostheses, irradiated autografts, and ice-cream cone prostheses. These scores were significantly lower if patients had deep infection (P = .035), which was the most common complication (28%) in structural reconstructions but did not occur in hip transposition even when performed after preoperative RT.

CONCLUSION

Acetabular reconstruction with hip transposition resulted in no deep infection and superior function in patients with pelvic ES even when combined with preoperative RT, which improved tumor necrosis and rate of local control and survival.

Preoperative surgical risk stratification in osteosarcoma based on the proximity to the major vessels

Aims

The aim of this study was to determine the risk of local recurrence and survival in patients with osteosarcoma based on the proximity of the tumour to the major vessels.

Patients and Methods

A total of 226 patients with high-grade non-metastatic osteosarcoma in the limbs were investigated. Median age at diagnosis was 15 years (4 to 67) with the ratio of male to female patients being 1.5:1. The most common site of the tumour was the femur (n = 103) followed by tibia (n = 66). The vascular proximity was categorized based on the preoperative MRI after neoadjuvant chemotherapy into four types: type 1 > 5 mm; type 2 ≤ 5 mm, > 0 mm; type 3 attached; type 4 surrounded.

Results

Limb salvage rate based on the proximity type was 92%, 88%, 51%, and 0% for types 1 to 4, respectively, and the overall survival at five years was 82%, 77%, 57%, and 67%, respectively (p < 0.001). Local recurrence rate in patients with limb-salvage surgery was 7%, 8%, and 22% for the types 1 to 3, respectively (p = 0.041), and local recurrence at the perivascular area was observed in 1% and 4% for type 2 and 3, respectively. The mean microscopic margin to the major vessels was 6.9 mm, 3.0 mm, and 1.4 mm for types 1 to 3, respectively. In type 3, local recurrence-free survival with limb salvage was significantly poorer compared with amputation (p = 0.025), while the latter offered no overall survival benefit. In this group of patients, factors such as good response to chemotherapy or limited vascular attachment to less than half circumference or longitudinal 10 mm reduced the risk of local recurrence.

Conclusion

The proximity of osteosarcoma to major blood vessels is a poor prognostic factor for local control and survival. Amputation offers better local control for tumours attached to the blood vessels but does not improve survival. Limb salvage surgery offers similar local control if the tumour attachment to blood vessels is limited. Cite this article: Bone Joint J 2019;101-B:1024–1031.

Mechanisms of failure and survival of total femoral endoprosthetic replacements

AIMS

The aim of this study was to evaluate the prosthesis characteristics and associated conditions that may modify the survival of total femoral endoprosthetic replacements (TFEPR).

PATIENTS AND METHODS

In all, 81 patients treated with TFEPR from 1976 to 2017 were retrospectively evaluated and failures were categorized according to the Henderson classification. There were 38 female patients (47%) and 43 male patients (53%) with a mean age at diagnosis of 43 years (12 to 86). The mean follow-up time was 10.3 years (0 to 31.7). A survival analysis was performed followed by univariate and multivariate Cox regression to identify independent implant survival factors.

RESULTS

The revision-free survival of the implant was 71% at five years and 63.3% at ten years. Three prostheses reached 15 years without revision. The mean Musculoskeletal Tumor Society score in the group was 26 (23 to 28). The mechanisms of failure were infection in 18%, structural failures in 6%, tumour progression in 5%, aseptic loosening in 2%, and soft-tissue failures in 1%. Prostheses used for primary reconstruction after oncological resections had lower infection rates than revision implants (8% vs 25%; p = 0.001). The rates of infection in silver-coated and non-silver-coated prosthesis were similar (17.4% vs 19.%; p = 0.869). The incidence of hip dislocation was 10%. Rotating hinge prosthesis had a lower failure rate than fixed hinge prosthesis (5.3% vs 11%). After Cox regression, the independent factors associated with failures were the history of previous operations (hazard ratio (HR) 3.7; p = 0.041), and the associated arthroplasty of the proximal tibia (HR 3.8; p = 0.034). At last follow-up, 11 patients (13%) required amputation.

CONCLUSION

TFEPR offers a reliable reconstruction option for massive bone loss of the femur, with a good survival when the prosthesis is used as a primary implant. The use of a rotating hinge at the knee and dual mobility bearing at the hip may be adequate to reduce the risk of mechanical and soft-tissue failures. Infection remains the main concern and there is insufficient evidence to support the routine use of silver-coated endoprosthesis. Cite this article: Bone Joint J 2019;101-B:522-528.

Mini-open excision of osteoid osteoma using intraoperative O-arm/Stealth navigation

BACKGROUND

Although osteoid osteomas have traditionally been treated by surgical excision, radiofrequency ablation (RFA) has gained favor as a less invasive procedure. However, RFA is contraindicated for osteoid osteomas close to the skin or crucial neurovascular structures, and is not covered by national health insurance in Japan. The aim of the present study was to evaluate the efficacy of surgical excision of osteoid osteomas using intraoperative navigation.

METHODS

We performed a retrospective review of five patients with osteoid osteoma who underwent a mini-open excision using O-arm/Stealth navigation at our institution. The osteoid osteomas were excised using a cannulated cutter or curetted out with the assistance of navigation.

RESULTS

Complete excision was achieved in all patients, which was confirmed by pathological examination. The mean skin incision was 2.1 cm (range, 1.5 to 3.0 cm) and the mean duration required for setup three-dimensional image was 15 min (range, 12 to 20 min). Although the mean visual analog scale score was 7 (range, 4 to 8) before surgery, all patients experienced relief from their characteristic pain immediately after surgery, with the mean scores of 2.2 (range, 1 to 3) and 0 at 2 days and 4 weeks after surgery, respectively. There was no intra-operative complication related to the navigation and no recurrence was observed during the mean follow-up period of 25 months (range, 13 to 33 months).

CONCLUSIONS

Mini-open excision using intraoperative O-arm/Stealth navigation is a safe and accurate procedure for patients with osteoid osteoma, which could cover the limitation of RFA.

Prognostic factors for local recurrence in extremity-located giant cell tumours of bone with pathological fracture

AIMS

The aim of this paper was to investigate the prognostic factors for local recurrence in patients with pathological fracture through giant cell tumours of bone (GCTB).

PATIENTS AND METHODS

A total of 107 patients presenting with fractures through GCTB treated at our institution (Royal Orthopaedic Hospital, Birmingham, United Kingdom) between 1995 and 2016 were retrospectively studied. Of these patients, 57 were female (53%) and 50 were male (47%).The mean age at diagnosis was 33 years (14 to 86). A univariate analysis was performed, followed by multivariate analysis to identify risk factors based on the treatment and clinical characteristics.

RESULTS

The initial surgical treatment was curettage with or without adjuvants in 55 patients (51%), en bloc resection with or without reconstruction in 45 patients (42%), and neoadjuvant denosumab, followed by resection (n = 3, 3%) or curettage (n = 4, 4%). The choice of treatment depended on tumour location, Campanacci tumour staging, intra-articular involvement, and fracture displacement. Neoadjuvant denosumab was used only in fractures through Campanacci stage 3 tumours. Local recurrence occurred in 28 patients (25%). Surgery more than six weeks after the fracture did not affect the risk of recurrence in any of the groups. In Campanacci stage 3 tumours not treated with denosumab, en bloc resection had lower local recurrences (13%), compared with curettage (39%). In tumours classified as Campanacci 2, intralesional curettage and en bloc resections had similar recurrence rates (21% and 24%, respectively). After univariate analysis, the type of surgical intervention, location, and the use of denosumab were independent factors predicting local recurrence. Further surgery was required 33% more often after intralesional curettage in comparison with resections (mean 1.59, 0 to 5 vs 1.06, 0 to 3 operations). All patients treated with denosumab followed by intralesional curettage developed local recurrence.

CONCLUSION

In patients with pathological fractures through GCTB not treated with denosumab, en bloc resection offers lower risks of local recurrence in tumours classified as Campanacci stage 3. Curettage or resections are both similar options in terms of the risk of local recurrence for tumours classified as Campanacci stage 2. The benefits of denosumab followed by intralesional curettage in these patients still remains unclear.

Comparison of minimally invasive and non-invasive systems in lengthening total femoral prostheses

Aims

The aim of this study was to describe, analyze, and compare the survival, functional outcome, and complications of minimally invasive (MI) and non-invasive (NI) lengthening total femoral prostheses.

Patients and Methods

A total of 24 lengthening total femoral prostheses, 11 MI and 13 NI, were implanted between 1991 and 2016. The characteristics, complications, and functional results were recorded. There were ten female patients and ten male patients. Their mean age at the time of surgery was 11 years (2 to 41). The mean follow-up was 13.2 years (seven months to 29.25 years). A survival analysis was performed, and the failures were classified according to the Modified Henderson System.

Results

The overall implant survival was 79% at five, ten, and 20 years for MI prostheses, and 84% at five years and 70% at ten years for NI prostheses. At the final follow-up, 13 prostheses did not require further surgery. The overall complication rate was 46%. The mean revision-free implant survival for MI and NI prostheses was 59 months and 49 months, respectively. There were no statistically significant differences in the overall implant survival, revision-free survival, or the distribution of complications between the two types of prosthesis. Infection rates were also comparable in the groups (9% vs 7%; p = 0.902). The rate of leg-length discrepancy was 54% in MI prostheses and 23% in NI prostheses. In those with a MI prosthesis, there was a smaller mean range of movement of the knee (0° to 62° vs 0° to 83°; p = 0.047), the flexion contracture took a longer mean time to resolve after lengthening (3.3 months vs 1.07 months; p < 0.001) and there was a lower mean Musculoskeletal Tumor Society (MSTS) score (24.7 vs 27; p = 0.295).

Conclusion

The survival and complications of MI and NI lengthening total femoral prostheses are comparable. However, patients with NI prosthesis have more accurate correction of leg-length discrepancy, a better range of movement of the knee and an improved overall function.