Did the dislocation risk after primary total hip arthroplasty decrease over time? A meta-analysis across six decades.

BACKGROUND: While continuous optimization is attempted to decrease the incidence of dislocation after total hip arthroplasty (THA), dislocation remains a major complication. This meta-analysis aims to analyze the evolution of the dislocation risk after primary THA over the decades and to evaluate its potential publication bias. PATIENTS AND METHODS: A systematic search was performed according to the PRISMA guidelines for this meta-analysis in the literature published between 1962 and 2020. MEDLINE, Cochrane and Embase databases were searched for studies reporting the dislocation risk and length of follow-up. Studies that reported on revision rates only and did not mention separate dislocations were excluded. All study designs were eligible. Study quality was assessed by existing quality assessment tools adjusted for arthroplasty research. Overall risk and yearly dislocation rates were calculated and related to historical time frame, study design, sample size and length of follow-up. RESULTS: In total, 174 studies were included with an overall moderate quality. In total there were 85.209 dislocations reported in 5.030.293 THAs, showing an overall dislocation risk of 1.7%, with a median follow-up of 24 months. The overall dislocation risk classified per decade decreased from 3.7% in 1960-1970 to 0.7% in 2010-2020. The yearly dislocation rate decreased from 1.8 to 0.7% within these same decades. There was no significant correlation between the reported dislocation risk and the duration of follow-up (p = 0.903) or sample size (p = 0.755). The reported dislocation risk was higher in articles with registry data compared to other study designs (p = 0.021). CONCLUSION: The dislocation risk in THA has been decreasing over the past decades to 0.7%. Non-selective registry studies reported a higher dislocation risk compared to studies with selective cohorts and RCTs. This indicates that the actual dislocation risk is higher than often reported and 'real-world data' are reflected better in large-scale cohorts and registries.

Current Evidence for Spinopelvic Characteristics Influencing Total Hip Arthroplasty Dislocation Risk.

BACKGROUND: Decreased pelvic mobility and pelvic retroversion may result from spinal degeneration and lead to changes in the orientation of the acetabular implant after total hip arthroplasty (THA). While multiple patient and surgery-related factors contribute to THA dislocations, there is increasing evidence that sagittal spinopelvic dynamics are relevant for THA stability. The aim of this systematic review was to assess the relationship between previously described sagittal spinopelvic characteristics and implant dislocations after primary THA. METHODS: A comprehensive literature search in the PubMed and Embase databases was conducted for studies reporting on spinopelvic morphology, alignment, pathology, or surgery and THA dislocations. Risk of bias was assessed using the MINORS criteria. Because of high heterogeneity in study methodology, a synthesis of best evidence was performed. Odds ratios (ORs), relative risks (RRs), and effect sizes (g) were calculated. RESULTS: Fifteen studies (1,007,900 THAs) with quality scores of 15 to 23 out of 24 were included. Nine different spinopelvic alignment parameters (8 studies, g = 0.14 to 2.02), spinal pathology (2 studies, OR = 1.9 to 29.2), and previous spinal fusion surgery (8 studies, OR = 1.59 to 23.7, RR = 3.0) were found to be related to THA dislocation. Conflicting results were found for another sagittal pelvic morphology parameter, pelvic incidence. CONCLUSIONS: Several sagittal spinopelvic patient characteristics were found to be related to THA dislocation, and the associated risks were greater than for other patient and surgery-related factors. Future research is needed to determine which of those characteristics and parameters should be taken into account in patients undergoing primary THA. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The SNAP Trial: 2-Year Results of a Double-Blind Multicenter Randomized Controlled Trial of a Silicon Nitride Versus a PEEK Cage in Patients After Lumbar Fusion Surgery.

STUDY DESIGN: Randomized controlled trial. OBJECTIVES: Lumbar interbody fusion with cages is performed to provide vertebral stability, restore alignment, and maintain disc and foraminal height. Polyetheretherketone (PEEK) is commonly used. Silicon nitride (Si3N4) is an alternative material with good osteointegrative properties. This study was designed to assess if Si3N4 cages perform similar to PEEK. METHODS: A non-inferiority double-blind multicenter RCT was designed. Patients presenting with chronic low-back pain with or without leg pain were included. Single- or double-level instrumented transforaminal lumbar interbody fusion (TLIF) using an oblique PEEK or Si3N4 cage was performed. The primary outcome was the Roland-Morris Disability Questionnaire (RMDQ). The non-inferiority margin for the RMDQ was 2.6 points on a scale of 24. Secondary outcomes included the Oswestry Disability Questionnaire (ODI), Visual Analogue Scales (VAS), SF-36 Physical Function, patient and surgeon Likert scores, radiographic evaluations for subsidence, segmental motion, and fusion. Follow-up was planned at 3, 6, 12, and 24-months. RESULTS: Ninety-two patients were randomized (i.e. 48 to PEEK and 44 to Si3N4). Both groups showed good clinical improvements on the RMDQ scores of up to 5-8 points during follow-up. No statistically significant differences were observed in clinical and radiographic outcomes. Mean operative time and blood loss were statistically significantly higher for the Si3N4 cohort. Although not statistically significant, there was a higher incidence of complications and revisions associated with the Si3N4 cage. CONCLUSIONS: There was insufficient evidence to conclude that Si3N4 was non-inferior to PEEK.

Uncemented total hip arthroplasty; increased risk of early periprosthetic fracture requiring revision surgery in elderly females.

PURPOSE: The preferred method of stem fixation in total hip arthroplasty (THA) remains debatable. Uncemented THA favors a lower rate of aseptic loosening but has an increased risk of early periprosthetic fractures (EPF). We hypothesize that routine placement of uncemented THA by experienced surgeons diminishes this EPF-risk. The purpose of this study is to investigate the effect of age, gender, ASA classification and BMI of THA performed by experienced surgeons on the risk of EPF. METHODS: A retrospective cohort study including all primary THAs and revision surgeries performed between 2012 and 2018. Possible predictive factors included are age, gender, BMI, ASA classification, presence of osteoporosis, Dorr classification, revision surgery type and clinical outcome. A number needed to treat (NNT) analysis was conducted assuming that cementing THA prevents EPF. RESULTS: 2635 primary THAs were performed. Indications for 70 revisions included 18 EPF in uncemented THA female patients. Periprosthetic fractures without a relevant trauma occurred within six weeks in 16 patients. There was a statistically significant correlation between EPF-risk and age (P = 0.032), female gender (P = 0.001) and ASA classification (P = 0.015). For age ≥75, there was an increase in EPF (P = 0.047). With the assumption that cementing would prevent EPF, the NNT is 48. No statistically significant correlation was found between EPF and BMI, osteoporosis or Dorr classification. CONCLUSION: Female patients aged ≥75 have an increased EPF-risk after uncemented THA and would therefore benefit from treatment with a cemented stem. An ASA score of III-IV is an independent risk factor for EPF after uncemented THA.

Heterotopic ossification in primary total hip arthroplasty using the posterolateral compared to the direct lateral approach.

PURPOSE: Total hip arthroplasty (THA) is a successful procedure. However, in time, heterotopic ossification (HO) can form due to, amongst others, soft tissue damage. This can lead to pain and impairment. This study compares the formations of HO between patients who underwent either THA with the posterolateral approach (PA) or with the direct lateral approach (DLA). Our hypothesis is that patients who underwent THA with a PA form less HO compared to THA patients who underwent DLA. METHODS: In this prospective cohort study, 296 consecutive patients were included who underwent THA. A total of 127 patients underwent THA with the PA and 169 with the DLA. This was dependent on the surgeon's preference and experience. More than 95% of patients had primary osteoarthritis as the primary diagnosis. Clinical outcomes were scored using the Numeric Rating Scale (NRS) and Harris Hip Score (HHS), radiological HO were scored using the Brooker classification. Follow-up was performed at 1 and 6 years postoperatively. RESULTS: Two hundred and fifty-eight patients (87%) completed the 6-year follow-up. HO formation occurred more in patients who underwent DLA, compared to PA (43(30%) vs. 21(18%), p = 0.024) after 6 years. However, the presence of severe HO (Brooker 3-4) was equal between the DLA and PA (7 vs. 5, p = 0.551). After 6 years the HHS and NRS for patient satisfaction were statistically significant higher after the PA (95.2 and 8.9, respectively) compared to the DLA (91.6 and 8.5, respectively) (p < 0.001 and p = 0.003, respectively). The NRS for load pain was statistically significant lower in the PA group (0.5) compared to the DLA group (1.2) (p = 0.004). The NRS for rest pain was equal: 0.3 in the PA group and 0.5 in the DLA group. CONCLUSION: THA with the PA causes less HO formation than the DLA. TRIAL REGISTRATION: Registrated as HipVit trial, NL 32832.100.10, R-10.17D/HIPVIT 1. Central Commission Human-Related research (CCMO) Registry.

The Survivorship of the Uncemented Iso-Elastic Monoblock Acetabular Component at a Mean of 6-Year Follow-up.

BACKGROUND: Aseptic loosening, caused by wear and osteolysis, is the most frequent reason for hip replacement revision in the UK. To prevent aseptic loosening, an acetabular component with vitamin E added to irradiated highly cross-linked polyethylene (HXLPE) was developed to reduce oxidative degradation. QUESTIONS/PURPOSES: A prior study of the vitamin E-blended HXLPE acetabular component after 2 years of follow-up reported no adverse reactions or abnormal mechanical behavior. To further examine this hypothesis of reducing wear and osteolysis, we sought to evaluate outcomes after 6-year follow-up. METHODS: A cohort of 95 of the 112 initial patients (84.2%) completed the 6 years of follow-up after receiving a vitamin E-blended HXLPE acetabular component. Evaluation was performed in terms of clinical (visual analog scale [VAS] score, VAS score with weight-bearing, VAS score for satisfaction, and Harris Hip Score) and radiological (inclination, polar gap, radiolucencies, migration, and 2-D linear femoral head penetration rate) assessment. RESULTS: The mean VAS score for patient satisfaction was 8.75 and the mean Harris Hip Score was 91.8. There were two revisions because of deep infections and one because of a peri-prosthetic femoral fracture. Two acetabular components migrated initially; however, delayed acetabular stabilization occurred. Both patients had good clinical scores at 72 months. The mean femoral head penetration rate was 0.036 mm/year. CONCLUSIONS: This prospective cohort study has shown no adverse reactions concerning the vitamin E additive, promising wear rates, no signs of osteolysis, a 100% survival rate for aseptic loosening, and an all-cause survivorship percentage of 97.4% at 6 years of follow-up.

Trigonometric Algorithm Defining the True Three-Dimensional Acetabular Cup Orientation: Correlation Between Measured and Calculated Cup Orientation Angles.

BACKGROUND: Acetabular cup orientation plays a key role in implant stability and the success of total hip arthroplasty. To date, the orientation has been measured with different imaging modalities and definitions, leading to lack of consensus on optimal cup placement. A 3-dimensional (3D) concept involving a trigonometric description enables unambiguous definitions. Our objective was to test the validity and reliability of a 3D trigonometric description of cup orientation. METHODS: Computed tomographic scans of the pelvis, performed for vascular assessment of 20 patients with 22 primary total hip replacements in situ, were systematically collected. On multiplanar reconstructions, 3 observers independently measured cup orientation retrospectively in terms of coronal inclination, sagittal tilt, and transverse version. The angles measured in 2 planes were used to calculate the angle in the third plane via a trigonometric algorithm. For correlation and reliability analyses, intraobserver and interobserver differences between measured and calculated angles were evaluated with use of the intraclass correlation coefficient (ICC). RESULTS: Measured and calculated angles had ICCs of 0.953 for coronal inclination, 0.985 for sagittal tilt, and 0.982 for transverse version. Intraobserver and interobserver reliability had ICCs of 0.987 and 0.987, respectively, for coronal inclination; 0.979 and 0.981, respectively, for sagittal tilt; and 0.992 and 0.978, respectively, for transverse version. CONCLUSIONS: The 3D concept with its trigonometric algorithm is a valid and reliable tool for the measurement of cup orientation. CLINICAL RELEVANCE: By calculating the transverse version of cups from coronal inclination and sagittal tilt measurements, the trigonometric algorithm enables a 3D definition of cup orientation, regardless of the imaging modality used. In addition, it introduces sagittal tilt that, like pelvic tilt, rotates around the transverse axis.

Precision and accuracy of imageless navigation versus freehand implantation of total hip arthroplasty: A systematic review and meta-analysis.

BACKGROUND: Total hip arthroplasty (THA) is named the most successful surgical procedure of the twentieth century. To remain a success in the twenty-first century THA should meet the higher demands of patients and society with regard to technical and functional outcome, costs and implant survival. To meet these demands optimal acetabular cup positioning is necessary. An imageless navigation system (NAV) might prevent malpositioning of the acetabular cup in THA. The aim of this study has been to compare the precision and accuracy of the anteversion and inclination of the acetabular cup position after NAV implantation and after freehand implantation of THA. METHODS: A systematic review and meta-analysis was conducted to assess the precision (variance) and accuracy (deviation from the target) from all available high-quality randomised control trials to date. RESULTS: Six out of seven studies concluded a statistically significant difference in precision in anteversion between the NAV group and the freehand group. Five out of seven studies concluded a statistically significant difference in precision in inclination. There is a significantly better accuracy for the NAV group than for the freehand group for anteversion (p = 0.002) and for inclination (p = 0.01). CONCLUSION: This study showed that NAV placement is more precise and has an improved accuracy for anteversion and inclination than freehand placement of the acetabular cup. However, there is a lack of evidence to support an improved functional outcome and a reduction of complications and revisions.

[A woman with inguinal pain after a bone marrow biopsy]. / Een vrouw met pijn in de lies na beenmergpunctie.

Haemorrhaging after a bone marrow biopsy is a rare but possibly life-threatening event. We describe a case of a retroperitoneal haemorrhage after a routine bone marrow biopsy in a 77-year-old woman who presented the day after the procedure with inguinal pain.

Quality of intraoperatively salvaged unwashed blood in hip arthroplasty.

BACKGROUND AND OBJECTIVES: Transfusion of autologous whole blood is one available method to reduce the need for allogenic blood transfusion. The aim of the present study was to investigate the quality of shed blood collected in a new intraoperative autotransfusion system. MATERIALS AND METHODS: In this prospective study fifteen consecutive patients who were scheduled for elective total hip arthroplasty were included. Shed blood was collected with a novel intraoperative autologous blood transfusion system (Sangvia®, AstraTech) from the surgical wound. Blood samples were taken from the transfusion bag. RESULTS: Mean blood loss during operation was 364ml (190-750ml) and mean transfused blood volume was 200ml (30-700ml). Mean haemoglobin concentration was 62g/l (17-91g/l) and mean plasma free haemoglobin concentration was 6.7g/l (1.9-12.7g/l) in transfusion blood. CONCLUSION: The basic laboratory characteristics of intraoperatively salvaged blood with the Sangvia® system are generally in the same range as reported in the studies on the postoperative transfusion of unwashed blood. From a blood quality point of view, our study indicates that transfusion of intraoperatively salvaged unwashed blood with the Sangvia® system in patients undergoing total hip arthroplasty is expected to be safe.

Interdisciplinary inter-observer agreement and accuracy of MR imaging of the shoulder with arthroscopic correlation.

INTRODUCTION: Differences between radiologists and orthopaedic surgeons in the interpretation of MR images of the shoulder joint are experienced in daily clinical practice. This study set out to evaluate the inter-observer agreement between radiologists and orthopaedic surgeons in assessing pathology on MR imaging of the shoulder joint. Also, we determined the accuracy of the observers with arthroscopy as the standard of reference. MATERIALS AND METHODS: Two radiologists and one orthopaedic surgeon reviewed 50 MR studies-25 conventional MR examinations and 25 MR arthrographies-of patients with shoulder complaints who had undergone MR imaging and subsequently arthroscopic surgery. The assessment was independent and blinded. All observers evaluated the MR examinations twice. Standard evaluation forms were used to score for pathology of rotator cuff, glenoid labrum, tendon of the long head of the biceps brachii and glenohumeral ligaments. The presence or absence of osteoarthritis, SLAP lesions, Bankart lesions, Hill-Sachs lesions or impingement was also noted. Intra- and inter-observer agreement, the sensitivity and specificity were calculated. Differences in percentages of correctly diagnosed lesions were tested for significance using McNemar's test. RESULTS: There was a poor inter-observer agreement between the orthopaedic surgeon and the radiologists in assessing Bankart lesions and ligamentous lesions. We found significant differences between the radiologists and the orthopaedic surgeon in the assessment of osteoarthritis, Hill-Sachs lesions and impingement. CONCLUSION: The orthopaedic surgeon and radiologists differed in their interpretation of what defines a Bankart lesion and what defines a ligamentous lesion. The orthopaedic surgeon was significantly more accurate in assessing impingement.

Resorbability of rigid beta-tricalcium phosphate wedges in open-wedge high tibial osteotomy: a retrospective radiological study.

The open-wedge high tibial osteotomy (OWHTO) is a well accepted treatment modality for patients with osteoarthritis of the medial compartment associated with genu varum. To fill in the osteotomy gap 30% macroporosity rigid beta-tricalcium phosphate (beta-TCP) is frequently used as a stable resorbable bone substitute. However, the resorbability of these beta-TCP wedges is not known. The aim of this study was to investigate this. Twenty-one OWHTO procedures in seventeen patients were performed with the use of 30% macroporosity rigid beta-TCP wedges. The osteotomies were fixed using an angle-stable locking plate. Conventional AP and lateral radiographs were examined in order to assess the resorbability of the 30% macroporosity rigid beta-TCP wedges as a function of time. A radiological classification system consisting of five phases was used to monitor the resorption of the 30% macroporosity rigid beta-TCP wedges. The mean duration of follow-up was 62 months (+/-23 range of 28-99). In all 21 cases, remnants of the 30% macroporosity rigid beta-TCP wedges were still present at maximum follow-up. Although the boundaries between 30% macroporosity rigid beta-TCP wedges and bone remained slightly visible, all osteotomies were completely consolidated and full osseointegration took place. In 16 out of 21 knees the fixation system was removed after a mean duration of 32 months (+/-19 range of 6-62). In six out of 21 knees a conversion to a knee arthroplasty was performed after a mean duration of 56 months (+/-18 range of 37-82). The OWHTO did not interfere with the placement of knee prostheses. Complete resorption of 30% macroporosity rigid beta-TCP wedges did not take place up to 8 years after operation.

Results of 101 aneurysms treated with polyglycolic/polylactic acid microfilament nexus coils compared with historical controls treated with standard coils.

BACKGROUND AND PURPOSE: Polyglycolic/polylactic acid (PGLA) addition to bare platinum coils is intended to reduce the reopening rate of coiled intracranial aneurysms. Nexus coils are standard complex platinum coils with interwoven PGLA microfilament threads. We present the clinical results of 101 intracranial aneurysms treated with Nexus coils. MATERIALS AND METHODS: Results of coiling of 101 aneurysms treated with Nexus coils were compared with our results of coiling of 120 aneurysms with Guglielmi detachable coils (GDC 10) and 115 with Trufill coils treated between May 2003 and December 2004 with the same treatment protocol. Rate of complications, mean aneurysmal volume, packing attenuation, incomplete aneurysmal occlusion at 6 months, and rates of retreatment were compared. RESULTS: Initial occlusion in aneurysms treated with Nexus coils was (near) complete in 97 aneurysms and incomplete in 4 aneurysms. There were no permanent procedural complications (0/95 patients, 0%; 97.5% CI, 0.0% to 3.3%). Mean aneurysmal volume was 180.2 mm(3) (range, 5-1624 mm(3)). Mean packing was 19.4% (range, 7.5% to 38.9%). Six months' angiographic follow-up in 87 of 101 aneurysms showed incomplete occlusion in 14 (16%), and 12 (14%) of those had additional coiling. Mean packing of 19.4% of Nexus coils was significantly lower than 22.9% for GDC 10 and 29.7% for Trufill coils. Other clinical results were not significantly different. CONCLUSION: In this series, PGLA microfilament Nexus coils were safe to use with clinical results comparable with those of standard platinum coils. This study gives additional evidence of the lack of beneficial effect of PGLA addition to reduce the reopening rate of coiled intracranial aneurysms.

3D rotational angiography: the new gold standard in the detection of additional intracranial aneurysms.

BACKGROUND AND PURPOSE: During surgery of symptomatic aneurysms, additional small angiographic occult aneurysms are commonly found. With 3D rotational angiography (3DRA) small aneurysms are more easily depicted than with digital subtraction angiography (DSA). In this study we compare 3DRA with DSA in the depiction of small additional aneurysms. MATERIALS AND METHODS: Three hundred fifty 3D datasets of 1 vascular tree of 350 patients with at least 1 intracranial aneurysm on the dataset were re-evaluated for the presence of additional aneurysms by 2 observers in consensus. Two other observers, blinded to the 3D images, re-evaluated DSA images of the same 350 vascular trees for these additional aneurysms. Results were compared. RESULTS: In 350 3D datasets, 350 target aneurysms and 94 additional aneurysms were detected. The mean size of 94 additional aneurysms was 3.54 mm (median, 3; range, 0.5-17 mm). The proportion of aneurysms

Fenestrations of the anterior communicating artery: incidence on 3D angiography and relationship to aneurysms.

BACKGROUND AND PURPOSE: Demonstration of fenestrations of the anterior communicating artery (AcomA) with conventional digital subtraction angiography is very uncommon. The purpose of this study was to assess the incidence of visible fenestrations of the AcomA on 3D rotational angiography (3DRA) and to evaluate the relationship between fenestrations of the AcomA and aneurysms of the AcomA. MATERIALS AND METHODS: We systematically reviewed 305 datasets of 3DRA of the internal carotid artery in 305 patients with aneurysms of the anterior circulation on a dedicated workstation for the presence of fenestrations on the AcomA. RESULTS: In 78 of 305 3DRAs, only the ipsilateral A2 segment was visible; thus, the AcomA could not be evaluated. Of the remaining 227 3DRAs, a fenestration of the AcomA was present in 12 (5.3%; 95% CI, 3.0%-9.1%). Of 12 fenestrations of the AcomA, 10 (83%) were associated with 1 or more aneurysms of the AcomA. Of 305 patients, 133 had an aneurysm on the AcomA, and in 127 of these, the AcomA was visible. Of 127 AcomA aneurysms with a visible AcomA, 10 were associated with fenestration, which accounted for an incidence of AcomA fenestrations with AcomA aneurysms of 7.9% (95% CI, 4.2%-14.0%). The proportion of fenestrations of the AcomA with aneurysms of the AcomA was 4.4% (10/227), and the proportion of AcomA fenestration with an aneurysm at another location was 0.9% (2/227). This difference was statistically significant (P = .040). Even in retrospect, 11 of 12 fenestrations were not visible on 2D DSA images. CONCLUSION: In selected patients with aneurysms of the anterior circulation, fenestrations in the AcomA were found with 3DRA in 5.3% of datasets. Most fenestrations were associated with 1 or more aneurysms of the AcomA.

Long-term 3T MR angiography follow-up after therapeutic occlusion of the internal carotid artery to detect possible de novo aneurysm formation.

BACKGROUND AND PURPOSE: The purpose of this study was to assess the incidence of de novo aneurysm formation, the incidence of subarachnoid hemorrhage (SAH), and the growth of existing untreated aneurysms in 52 patients after therapeutic carotid artery balloon occlusion for carotid aneurysms. PATIENTS AND METHODS: Between January 1996 and August 2004, 52 patients were treated with carotid artery balloon occlusion for carotid aneurysms. In June 2005, all patients, their next of kin, or family physicians were contacted and questioned concerning episodes of headache or hospital admissions that could be attributed to SAH. In addition, MR imaging and MR angiography (MRA) at 3T were performed in 26 of 44 surviving patients after a mean follow-up period of 50.2 months (median, 43.5 months; range, 14-107 months). MR imaging and MRA studies were compared with the digital subtraction angiograms at the time of carotid artery occlusion. RESULTS: During clinical follow-up of 52 patients at a mean of 50.3 months (median, 42.5 months; range, 0-107 months), no episodes of SAH were reported (0%; 97.5% confidence interval [CI], 0-8.2%). In the 26 patients with follow-up MR imaging, no de novo aneurysms were detected (0%; 97.5 CI, 0-13.2%). Five existing untreated small aneurysms in 5 patients had not enlarged after a mean follow-up of 40 months. CONCLUSION: In this study, therapeutic carotid artery occlusion was not associated with development of new aneurysms or enlargement of existing untreated aneurysms with time.

Coiling of truly incidental intracranial aneurysms.

BACKGROUND AND PURPOSE: The purpose of this study is to report the morbidity, mortality, and angiographic results of coiling of asymptomatic incidental aneurysms and compare the characteristics of these aneurysms with other asymptomatic incidental aneurysms that were not treated. PATIENTS AND METHODS: During a 10-year period, 97 patients without previous subarachnoid hemorrhage, presented with incidentally found intracranial aneurysms. In 48 patients, 58 aneurysms were coiled. The mean size of the 58 coiled incidental aneurysms was 10.9 mm (median, 9 mm; range, 3-40 mm). Twenty-six of 58 coiled aneurysms (44.8%) were > or = 10 mm. RESULTS: Permanent morbidity of coiling was 2.1% (1 of 48), mortality was 0%. Compared with untreated patients with incidental aneurysms, coiled patients were younger and more often had multiple aneurysms. Aneurysms of coiled patients more often had a small neck, were more often located on the carotid artery, and were less often located on the middle cerebral artery. Of 46 aneurysms with angiographic follow up, 45 were completely or near completely occluded. To obtain these results, 3 aneurysms were coiled more than once. Coiled incidental aneurysms did not rupture during a median follow-up period of 28.5 months. Mean hospital stay per patient was 2.5 days. CONCLUSION: Coiling of incidental intracranial aneurysms has a low complication rate in selected aneurysms and patients. Coiling should be the first treatment option in incidental aneurysms suitable for this technique.

Epidermal growth factor receptor targeting enhances adenoviral vector based suicide gene therapy of osteosarcoma.

BACKGROUND: Despite improvements in the treatment of osteosarcoma (OS) there are still too many patients who cannot benefit from current treatment modalities. Therefore, new therapeutic approaches are warranted. Here we explore the efficacy of targeted adenoviral based suicide gene therapy. METHODS AND RESULTS: Immunohistochemistry and FACS analysis detected low or absent expression levels of the primary adenovirus receptor CAR on human primary OS and human OS cell lines. These results predict a low infection efficiency and thus a reduced therapeutic effect. Targeting the adenoviruses to another receptor highly expressed on OS could overcome this limitation. We found epidermal growth factor receptor (EGFR) to be widely expressed on primary OS. Immunohistochemistry on primary tumor samples and FACS analysis on primary short-term cultures and four OS cell lines showed that EGFR was consistently expressed. The recombinant bispecific single-chain antibody 425-s11 redirects adenoviral vectors towards the EGFR. Adenovirus transduction experiments in the presence or absence of 425-s11 showed significantly enhanced gene transfer with the targeted adenoviral vector compared with the native vector (OS cell lines 2.5 to 7.2 times enhanced gene transfer and OS primary short term cultures 1.7 to 10 times enhanced gene transfer). On this basis, targeted suicide gene therapy experiments with AdCMVHSV-TK in combination with ganciclovir were performed. These experiments demonstrated up to 3.5-fold enhanced kill of OS cell lines and primary short-term cultures by the EGFR targeted vector. CONCLUSIONS: Suicide gene therapy with adenovirus targeted towards EGFR may have favorable therapeutic characteristics for future gene therapy applications in OS.

Retroversion of the humeral head in children with an obstetric brachial plexus lesion.

We undertook a prospective MRI study to measure the retroversion of the humeral head in 33 consecutive infants with a mean age of 1 year 10 months (3 months to 7 years 4 months) who had an obstetric brachial plexus lesion (OBPL). According to a standardised MRI protocol both shoulders and humeral condyles were examined and the shape of the glenoid and humeral retroversion determined. The mean humeral retroversion of the affected shoulder was significantly increased compared with the normal contralateral side (-28.4 +/- 12.5 degrees v -21.5 +/- 15.1 degrees, p = 0.02). This increase was found only in the children over the age of 12 months. In this group humeral retroversion was -29.9 +/- 12.9 degrees compared with -19.6 +/- 15.6 degrees in the normal shoulder (p = 0.009), giving a mean difference of 10.3 degrees (95% confidence interval 3.3 to 17.3). This finding is of importance when considering the operative treatment for subluxation of the shoulder in children with an OBPL.

Transforming growth factor beta-coated platinum coils for endovascular treatment of aneurysms: an animal study.

OBJECTIVE: To test the hypothesis that coating platinum coils with transforming growth factor beta (TGFbeta) would improve the cellular proliferation within experimental aneurysms relative to uncoated coils. MATERIALS AND METHODS: Elastase-induced saccular aneurysms were created in 12 New Zealand White rabbits. These aneurysms were embolized with platinum coils, either "control" (unmodified) coils or "test" (coated with TGFbeta) coils. Subjects were killed either 2 weeks (n = 3, control; n = 3, test) or 6 weeks (n = 3, control; n = 3, test) after embolization. Aneurysm tissue was embedded in plastic, sectioned, and stained with hematoxylin and eosin. The thickness of tissue covering the coils at the coil-lumen interface was measured by use of a digital microscope, and was compared between groups by use of the Student's t test (P < or = 0.05). RESULTS: Two-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 36+/-15 microm and mean thickness of overlying control coils of 3+/-5 microm, indicating significantly thicker tissue growth covering test versus control coils (P = 0.02). Six-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 86+/-74 microm versus mean thickness overlying control coils of 37+/-6 mu; this difference did not reach statistical significance (P = 0.30). Thickness of tissue covering TGFbeta-coated coils did not change significantly from 2 to 6 weeks (P = 0.31). Tissue thickness over control coils increased significantly between 2 and 6 weeks (P = 0.002). CONCLUSION: TGFbeta-coated platinum coils undergo earlier cellular coverage than standard platinum coils, but differences in coverage between coated and control coils are no longer present at later time points. These data suggest that improvements in intra-aneurysmal cellular proliferation resulting from coil modifications, although significant in the early postembolization phase, may dissipate over time.