Pelvic instability after bone graft harvesting from posterior iliac crest: report of nine patients

Objective. To report the imaging findings in nine patients who developed pelvic instability after bone graft harvest from the posterior aspect of the iliac crest. Design and patients. A retrospective study was performed of the imaging studies of nine patients who developed pelvic pain after autologous bone graft was harvested from the posterior aspect of the ilium for spinal arthrodesis. Plain films, bone scans, and CT and MR examinations of the pelvis were reviewed. Pertinent aspects of the clinical history of these patients were noted, including age, gender and clinical symptoms. Results. The age of the patients ranged from 52 to 77 years (average 69 years) and all were women. The bone graft had been derived from the posterior aspect of the iliac crest about the sacroiliac joint. All patients subsequently developed subluxation of the pubic symphysis. Eight patients had additional insufficiency fractures of the iliac crest adjacent to the bone graft donor site, and five patients also revealed subluxation of the sacroiliac joint. Two had insufficiency fractures of the sacrum and one had an additional fracture of the pubic ramus. Conclusions. Pelvic instability is a potential complication of bone graft harvesting from the posterior aspect of the iliac crest. The pelvic instability is manifested by insufficiency fractures of the ilium and subluxation of the sacroiliac joints and pubic symphysis. Received: 25 January 2000 Revision requested: 22 May 2000 Revision received: 15 September 2000 Accepted: 4 January 2001     

Three-phase radionuclide bone imaging in stress injury of the anterior iliac crest

Two adolescents with stress-related avulsion injury of the anterior iliac crest apophysis are presented. Increased tracer concentration in the anterior iliac crest area is present on the blood-pool and delayed images. Increased iliac crest activity was demonstrated on the radionuclide angiogram in one patient. Scintigraphic detection of this injury is useful when clinical findings are atypical, if objective evidence of a fracture is required, or when the fracture is not readily apparent radiographically.     

Cancellous bone structure of iliac crest biopsies following 370 days of head-down bed rest

INTRODUCTION: Static bone histomorphometry was applied to existing iliac bone sections originating from a 370-d 5 degrees head-down bed rest experiment. This bed rest experiment is the longest ever to have been conducted. We hypothesized that bed rest would decrease cancellous bone volume fraction and that this effect would be reversed by countermeasures. METHODS: Eight healthy male subjects underwent 370 d of 5 degrees head-down bed rest. Three subjects were treated with bisphosphonate (Xidifon, potassium salt of ethane-1-hydroxy-1-disphosphonate, EHDP) combined with an exercise regimen (1-2 h x d(-1)) for the entire study period. Five subjects underwent 120 d of bed rest without countermeasures followed by 250 d of bed rest with the exercise regimen. Transiliac bone biopsies were obtained either at baseline and day 366, or at baseline, day 116, and day 366 at alternating sides of the ileum. Static histomorphometry was performed using a computerized method. RESULTS: The 120 d of head-down bed rest without countermeasures resulted in decreased bone volume fraction BV/TV (-6.3%, p = 0.046) and trabecular number (Tb.N; -10.2%, p = 0.080) and increased trabecular separation (Tb.Sp; 14.7%, p = 0.020), whereas the 250 d of subsequent head-down bed rest with exercise treatment prevented further significant deterioration of the histomorphometric measures. DISCUSSION: The 120 d of 5 degrees head-down bed rest without countermeasures induced significant deterioration of iliac crest cancellous bone histomorphometric properties. On average, the countermeasures consisting of either bisphosphonate and exercise, or exercise alone were able to either prevent or stop immobilization-induced changes of the iliac cancellous bone structure.     

Vascular tumors of bone: Imaging findings

Purpose

To identify radiological features of malignant vascular tumors of bone, which can be used to avoid erroneously diagnosing metastases based on radiological multifocality, and histological epitheloid phenotype.

Materials and methods

From the databases of the Bologna & Netherlands Committee on Bone Tumors, 63 patients with a histological diagnosis of malignant vascular tumor of bone were retrieved. Epidemiological and imaging characteristics were recorded on a case record form.

Results

In 63 patients, 185 lesions were detected by radiographs (61 patients) and/or CT (30 patients) and/or MRI (19 patients). Multifocality was observed in 25 patients (40%), in these patients most lesions were located in the femur. Typically lesions were well-defined, osteolytic, had a geographically pattern of destruction and were also located in the femur. Most lesions showed cortical destruction (118 lesions). No periosteal reaction was seen in most cases (121 lesions). In 13 of 39 patients (33%) tumor extension was more advanced and/or (additional) lesions (29 lesions; 17%) were visible on MRI and CT. In 20 cases (51%) cortex destruction was better shown on CT or MRI. In six patients (15%) periosteal reaction was only seen on MRI or CT and not on radiographs. In 16 (41%) cases soft tissue extension was only seen on MRI or CT, and not on radiographs. Extensive reactive changes on T2-weighted images were seen in 11 patients (58%).

Conclusion

When single, or regional multifocal osteolytic, well-marginated lesions with cortical destruction are seen, in the femur, and with marked reactive soft tissue changes on MRI, a diagnosis of malignant vascular tumor should trigger the use of additional immunohistochemistry to confirm the vascular nature of the tumor.

Clinical relevance statement

Because of epithelioid phenotype at histology, radiological signs are key in entertaining a diagnosis of malignant vascular tumor of bone which should trigger the use of appropriate immunohistochemical stainings.     

Healing of the patellar tendon after harvesting of its mid-third for anterior cruciate ligament reconstruction and evolution of the unclosed donor site defect

The purpose of this study was (a) to evaluate by ultrasonography the healing of the patellar tendon after its mid-third was removed for anterior cruciate ligament (ACL) reconstruction in two randomized groups of patients in whom the tendon donor site was either left open or closed: (b) to compare clinical, radiographic, and isokinetic studies of these two groups to evaluate the incidence of patellofemoral disorders. We performed 61 ACL reconstructions (22 males, 39 females) using the arthroscopically assisted in-out technique. All operations were performed by the same surgeon, and the patients were all subjected to the same postoperative protocol. The tendon defect was left open in 25 subjects (group A) and was closed in 36 subjects (group B). Postoperative patellar tendon behavior was evaluated in these two groups by ultrasonography at 3, 6, 9, and 12 months. The vertical position of the patella was measured in the follow-up lateral view at 45° of flexion and compared to that of the untreated knee. A clinical evaluation was performed throughout the follow-up period. and patellofemoral problems (pain, stiffness, patellofemoral crepitus) were evaluated and recorded using a modified Larsen and Lauridsen rating scale. Isokinetic evaluation was carried out at 6 months, and a quadriceps index of the two groups was recorded. Ultrasonography showed that healing of the patellar tendon initially progressed with a compensatory hypertrophy in width and thickness. The width was greater in group B (P<0.01). In group A we observed in the cross-sections a characteristic image of two cords separated by a low signal bridge which we defined as a binocular pattern. Areas of high ultrasound signal intensities persisted after 1 year in the open group: such areas were filled with scar tissue. In the closed group the ultrasound tendon signal returned to normal at 1 year. At 6 months the clinical, radiographic and isokinetic findings did not significantly differ between the open and closed groups. We conclude that defect closure after patellar tendon harvesting does not significantly influence the extensor apparatus.     

Imaging findings of atypical mycobacterial infection in the temporal bone

Atypical mycobacterial (AM) infection of the temporal bone is rare, and its early diagnosis is critical for a good patient outcome. The imaging findings of AM infection have been only briefly reported. We present the computed tomographic and magnetic resonance findings of AM involvement of the entire temporal bone in an immunocompromised patient, and we discuss the differential diagnosis. The scattered areas of both bone sclerosis and erosion may help the radiologist suggest the diagnosis of an indolent process such as tuberculosis or AM and allow initiation of early treatment.     

Avulsion fracture of the iliac crest in a football player

We describe an unusual injury of the iliac crest in an adolescent football player. The injury occurred as a result of a sudden twist of the trunk while kicking. Plain radiographs showed avulsion fracture of the anterior part of the iliac crest apophysis. Five months later the injury was partially ossificated but the patient felt minor pain and was not confident of returning to playing football.     

How does iliac crest bone marrow biopsy compare with imaging in the detection of bone metastases in small cell lung cancer?

Iliac crest bone marrow biopsy (BMB) has often been used as the gold standard for the detection of bone marrow metastases in small cell lung cancer (SCLC). However, it is likely to lead to numerous false-negative results. For this reason, we compared the results of bone scintigraphy (BS), magnetic resonance imaging (MRI), and BMB in 48 sequential patients affected with pathologically confirmed SCLC (47 were evaluable; mean age, 58.4 years). The three procedures were carried out within 1 week, no treatment being performed during this period. Whole-body scans and spot views were obtained in the anterior and posterior projections. For MRI, only the thoracolumbar spine, the sternum and the pelvis were scanned, using spin-echo T1-weighted sequences, resulting in an acquisition time of less than 45 min. Only five BMBs were rated as positive. In these cases, both BS and MRI were also positive. The other 42 biopsies were negative. Among them, in ten cases both BS and MRI were positive. In 21 cases, both BS and MRI were negative. In five cases MRI was positive while BS was negative. Finally, in six cases MRI was negative whilst BS was positive. In most cases in which either BS or MRI was positive, follow-up scans confirmed the initial findings. This study suggests that BMB is more invasive and less sensitive than BS or MRI in detecting bone metastases. MRI seems to be more sensitive than BS in detecting small spinal or pelvic metastases. Whole-body bone scintigraphy is more sensitive in detecting skull, costal or peripheral metastases. BS and MRI should be used in combination and may replace BMB in the detection of bone metastases in SCLC. Correspondence to: I. Perrin-Resche     

Imaging findings of the developing temporal bone in fetal specimens.

PURPOSETo trace the development of the normal fetal temporal bone by means of plain radiography, MR, and CT.METHODSEighteen formalin-fixed fetal specimens, 13.5 to 24.4 weeks'' gestational age, were examined with a mammographic plain film technique, CT, and MR imaging at 1.5 T. Temporal bone development and ossification were assessed.RESULTSThe membranous labyrinth grows with amazing rapidity and attains adult size by the middle of the gestation period. The cochlea, vestibule, and semicircular canals are very prominent and easily recognized on MR images. The otic capsule develops from a cartilage model. Ossification of the otic capsule proceeds rapidly between 18 and 24 weeks from multiple ossification centers that replace the cartilaginous framework. The mastoid, internal auditory canal, vestibular aqueduct, and external auditory canal continue to grow after birth.CONCLUSIONThe study of fetal developmental anatomy may lead to a better understanding of congenital disorders of the ear. Faster MR scanning techniques may provide a method for in utero evaluation of the fetal temporal bone.     

骨纤维异常增殖症的影像学表现

骨纤维异常增殖症（fibrous dysplasia of bone）的病因尚未明确，可能与胚胎原始问叶组织发育异常有关。临床分三型，单骨型、多骨型和骨纤维异常增殖综合征，后者即Albright综合征，也称McCunAlbright综合征。本病一般发病于儿童期，以Albright综合征发病较早，平均发病年龄16岁，恶变率约0．5％。部分骨纤维异常增殖症患者直到青年期或成年期才发现病变。     

Pseudoaneurysms at aortic cannulation site after coronary artery bypass graft: MR findings.

Pseudoaneurysm at the aortic cannulation site is a rare but potentially fatal complication of coronary artery bypass surgery. We present two cases in which MRI provided significant information regarding the anatomy and extent of a pseudoaneurysm. In one case both spin-echo imaging and cine MRI with and without gradient moment nulling (flow compensation) were used. The absence of gradient moment nulling in cine MRI provides additional contrast between flowing and static blood. This contrast may complement conventional cine images with gradient moment nulling, providing further information.     

Serial magnetic resonance imaging of the donor site after harvesting the central third of the patellar tendon A prospective study of 37 patients after arthroscopic anterior cruciate ligament reconstruction

The aim of this prospective study was to follow the development of repair tissue in the donor-site area using serial magnetic resonance imaging (MRI) evaluation and to assess whether the MRI findings were correlated with donor-site morbidity. Thirty-seven consecutive patients with unilateral anterior cruciate ligament injuries undergoing elective reconstruction of the ligament were included in the study. They were aged 27 (range 14–50) years. The graft was harvested through two 25-mm vertical incisions with the aim of protecting the infrapatellar nerve and sparing the paratenon. The tendon defect was left open. The patients underwent MRI evaluation at 6 weeks, 6 months and 27 months postoperatively. A final clinical follow-up was made 25 (range 23–29) months postoperatively. MRI demonstrated that the donor-site gap, i.e. the area corresponding to a pathological non-tendinous-like tissue signal, was 9 (range 4–18) mm at 6 weeks, 5 (range 2–14) mm at 6 months and 2 (range 0–5) mm at 27 months. The size of the donor-site gap had significantly decreased at 6 months compared with 6 weeks (P = 0.0001), as well as at 27 months compared with 6 months (P = 0.0001). We conclude that the patellar tendon at the donor site healed gradually, as expressed by a decrease in the area of non-tendinous-like tissue signal on the serial MRI evaluations. Received: 3 March 1998 Accepted: 28 May 1998     

Venoocclusive liver disease after bone marrow transplantation: findings at duplex sonography.

Ascites, thickening of the gallbladder wall, and reversal of portal flow are documented sonographic findings in venoocclusive disease of the liver. The frequency and specificity of these findings and their relationship to the severity of this disease have not been studied. In an attempt to clarify these issues, 65 patients who had bone marrow transplantations were prospectively studied with serial B-scans and duplex color Doppler sonography. For all patients, assessment included liver size and texture, thickening of the gallbladder wall (greater than 10 mm), and presence of ascites. Doppler flow velocity profiles were obtained from the portal vein, hepatic veins, and inferior vena cava. The hepatic artery resistive index (RI) was calculated. Twenty volunteers were also studied to establish normal flow values. Nineteen patients had documented venoocclusive disease, nine had hepatic graft-vs-host disease (GVHD) (five after proved venoocclusive disease), two had hepatitis, and 40 had no clinical or biochemical evidence of liver injury after bone marrow transplantation. Ascites (n = 16), thickening of the gallbladder wall (n = 8), hepatomegaly (n = 8), and altered liver texture (n = 3) were not distinguishing features of venoocclusive disease. Mean hepatic artery RI was as follows (ranges are in parentheses): control group, 0.69 (0.58-0.76); venoocclusive disease patients, 0.81 (0.75-0.87); GVHD patients, 0.69 (0.63-0.71); all other patients after bone marrow transplantation, 0.66 (0.61-0.71). The RI values in venoocclusive disease were significantly elevated, but an incremental rise in RI with increasing severity of the disease was not seen. Abnormalities in portal vein flow were seen in only two patients: in one with fatal venoocclusive disease, reversed portal flow developed, and in one with GVHD, portal vein thrombosis developed. Contrary to previous reports, no correlation between abnormalities in portal flow and venoocclusive disease was seen. Flow velocities in the hepatic veins and the inferior vena cava were not significantly different from values in the volunteer group. These results suggest that a significant elevation of the hepatic artery RI may be a sensitive index of liver damage related to venoocclusive disease after bone marrow transplantation and an important distinguishing sonographic feature.     

骨巨细胞瘤合并动脉瘤样骨囊肿的影像学表现分析

目的：探讨骨巨细胞瘤（GCT）合并动脉瘤样骨囊肿（ABC）的影像学表现及鉴别特点,以提高其诊断水平。方法：回顾性分析经手术、病理证实的14例GCT合并ABC的影像学表现。所有患者均行X线检查,11例行CT检查,12例行MRI扫描,2例行全身骨显像。对其影像学表现和病理结果进行对照。结果：14例中,病灶位于股骨6例,胫骨3例,尺骨3例,腓骨1例,桡骨1例。X线及CT表现为膨胀性骨质破坏,病灶密度不均匀,皮质变薄或中断。肿瘤实质区T₁WI呈等或低信号、T₂WI呈以高信号为主的混杂信号,病灶内多伴囊变和液-液平面,病灶周围骨质水肿,增强扫描病灶大部分呈明显强化。全身骨现象主要表现为病变部位片状放射性核素浓聚,显影不均匀。结论：GCT合并ABC的CT、MRI表现具有一定特征,结合X线、全身骨显像检查,有助于提高该病的术前诊断准确率,为临床治疗方案的制订提供帮助。