Transient osteoporosis of the hip: A case report

We report a case of transient osteoporosis of the hip (TOH) in a 59-year-old man including the clinical presentation, diagnostic studies, management and clinical progress. TOH is a rare self-limiting condition that typically affects middle-aged men or, less frequently, women in the third trimester of pregnancy. Affected individuals present clinically with acute hip pain, limping gait, and limited ranges of hip motion. TOH may begin spontaneously or after a minor trauma. Radiographs are typically unremarkable but MR imaging studies yield findings consistent with bone marrow edema. TOH is referred to as regional migratory osteoporosis if it travels to other joints or the contralateral hip. TOH often resembles osteonecrosis but the two conditions must be differentiated due to different prognoses and management approaches. The term TOH is often used interchangeably and synonymously with transient bone marrow edema.     

A new hypothesis for the bone marrow edema pathogenesis during transient osteoporosis

Transient osteoporosis is an infrequent condition of uncertain etiology with pain, limited range of motion and radiographic evidence of osteoporosis affecting one or more joints. It is self-limited, reversible and can involve only the hip (transient osteoporosis of the hip, TOH) or, less frequently, one or more joints contemporaneously or at different times (regional migratory osteoporosis, RMO). We studied four men with transient osteoporosis, including two with TOH and two with RMO. All patients underwent a standard radiographic work-up of the affected joints, arteriovenous Doppler US, computed tomography, magnetic resonance imaging (MRI) and three-phase bone scanning. In all patients, symptoms were related to bone marrow edema demonstrated at MRI and to a transitory regional arterial hyperflow observed at the early scintigraphic analysis. On the basis of our observations, we hypothesize that regional arterial hyperflow may be the cause of the bone marrow edema and therefore of the transient osteoporosis.     

Pregnancy-related hip diseases: incidence and diagnoses

BackgroundPregnancy-related hip diseases epidemiology has been poorly evaluated. We report our experience of gestational and postpartum hip diseases and evaluate their incidence.Methods(1) Prospective survey: all pregnant or early postpartum women suspected to have hip involvement during their follow-up in an Obstetric unit were referred to a rheumatologist. If clinically confirmed, magnetic resonance imaging (MRI) and additional investigations as needed were performed. This survey had 2 years duration. (2) Retrospective study: all cases of definite (with MRI confirmation) pregnancy-related hip disease referred to our Rheumatology unit during the past 15 years were analyzed.ResultsDuring the 2-year prospective survey, 3 patients (4 hips) of pregnancy-related hip disease were observed over 4900 pregnancies (1 case of transient osteoporosis of the hip (TOH) and 2 cases of occult fracture of the femoral head). During the 15-year retrospective study, 12 patients (17 hips) with hip diseases during pregnancy or early postpartum were identified. There were 6 patients (9 hips) with TOH, 4 patients (6 hips) with occult fracture of the femoral head, 1 patient with osteonecrosis of the femoral head, and 1 coxitis in a patient with ankylosing spondylitis. Differentiating diagnosis between TOH and occult fractures could only be made by MRI. Five of the 6 women with TOH had osteopenia at the lumbar spine at dual energy X-ray absorptiometry (DEXA). The 4 women with occult fractures had either osteopenia or osteoporosis at the lumbar spine.ConclusionHip diseases are infrequent during pregnancy and early postpartum. Transient osteoporosis of the hip and occult stress fractures of the femoral head appear the main causes and those diagnoses justify evaluation for an underlying bone fragility. Osteonecrosis is very rare in this setting.     

髋关节一过性骨质疏松症的诊断与治疗

目的：探讨髋关节一过性骨质疏松症的诊断与治疗效果。方法：2005年1月至2010年2月采用保守方法治疗髋关节一过性骨质疏松症5例,均为男性;年龄27～46岁,平均38.6岁。对其临床表现、体格检查及影像学改变进行分析总结,采用Harris髋关节评分对治疗效果进行评价。结果：所有患者获随访,时间12～36个月,平均24个月。治疗前Harris髋关节评分分别为63.1、86.0、74.9、63.6、64.8分,治疗6个月后分别为90.5、94.5、89.7、93.9、87.8分。治疗6个月后,X线片及MRI影像均基本恢复正常。结论：髋关节一过性骨质疏松症有典型的临床及影像学表现,保守和对症处理对髋关节一过性骨质疏松症有效。     

Lumbar modic changes-a comparison between findings at low- and high-field magnetic resonance imaging

STUDY DESIGN.: A cross-sectional observational study. OBJECTIVE.: To investigate whether there is a difference in findings of lumbar Modic changes in low-field (0.3 T) magnetic resonance imaging (MRI) compared with high-field (1.5 T). SUMMARY OF BACKGROUND DATA.: It is a challenge to give patients with low back pain a specific diagnosis. Modic changes as seen on MRI have been reported to be a possible source of pain. However, it is unclear whether the diagnosis is independent on the field strength. METHODS.: Twenty patients with Modic changes, 11 women and 9 men (mean age, 53.6 yr; range, 29-81 yr), with or without sciatica, seen in a Danish outpatient low back pain clinic were included. All patients obtained MRI scans on both a high-field and a low-field MRI scanner. Two radiologists evaluated all lumbar endplates independently, using a standardized evaluation protocol. Kappa statistics were used to analyze the interobserver reproducibility. We used paired t test to analyze the difference between low- and high-field MRI. RESULTS.: The total number of Modic changes diagnosed with high-field MRI was significantly higher than that with low-field MRI. However, 3 to 4 times as many Modic type 1 changes were found with low-field MRI compared with high-field MRI. Contrarily, with high-field MRI type 2 changes were diagnosed twice as often. CONCLUSION.: There was a significant difference between low- and high-field MRI regarding the overall prevalence of any Modic change, but this had opposite directions for types 1 and 2: type 2 dominated in low field and conversely in high field. The type of MRI unit should be taken into consideration when diagnosing patients with Modic changes.     

Imaging diagnosis in femur head necrosis with emphasis on skeletal scintigraphy and magnetic resonance tomography

Early diagnosis and treatment of avascular necrosis (AVN) of the femoral heads improve the prognosis of this disorder. Of the different radiological studies available so far, none has been truly satisfactory. Conventional X-rays frequently show alterations in the femoral heads only in later stages. Early on these may be so subtle that they are overlooked by the examiner. Bone scintigraphy is more sensitive than conventional X-rays in the detection of early alterations, but there are still up to 18% negative studies in biopsy-proven femoral-head necrosis. The sensitivity of this method is also diminished when bilateral AVN is present. This is frequently the case even if only one hip joint is symptomatic. Computed tomography (CT) and single photon emission computed tomography (SPECT) are highly sensitive methods that are still not widely used for the diagnosis of AVN. With SPECT, clinical experience is still limited. A number of publications in recent years have revealed the excellent characteristics of magnetic resonance imaging (MRI) in showing the pathological processes in bone marrow and, in particular, AVN. This paper summarizes a few of these publications and our personal experience with MRI in AVN of the femoral head. Different cases examples are given.     

Transient Bone Marrow Edema in Renal Transplantation: A Distinct Post-transplantation Syndrome with a Characteristic MRI Appearance

We describe four patients who developed severe knee pain within 3 months of renal transplantation. Plain radiographs were normal and inflammatory markers (CRP, ESR) were all within normal ranges. Magnetic resonance imaging (MRI) showed a distinctive pattern in all four cases of bone marrow signal changes, extending from the epiphyseal region into the metaphyseal region in two cases. The appearances were different from those of avascular necrosis (AVN) and reflex sympathetic dystrophy and showed no progression to develop AVN during the follow-up period of 36 months. In all cases the pain resolved over a period of 3 months without specific therapy. Follow-up MRI scans were obtained in all patients after the pain had subsided, which revealed resolution of the MRI changes. We suggest that MRI be the investigation in such patients and that bone marrow edema changes will regress without the need to withdraw cyclosporin.     

Sickle cell disease and silent avascular necrosis of the hip

We reviewed the prevalence of avascular necrosis (AVN) in a series of patients with sickle cell disease, using radiography and magnetic resonance imaging. We found AVN of at least one hip in 11 of 27 patients (41%). This is a significantly greater prevalence than reported. MRI was not as helpful in patients with sickle cell disease as it is in patients with AVN from other causes; it detected no more cases than radiography.     

The course and treatment of avascular necrosis of the femoral head in developmental dysplasia of the hip

Proximal femoral growth disturbance, commonly referred to as avascular necrosis (AVN) of the femoral head in the literature, is a potentially devastating complication in the treatment of developmental dysplasia of the hip (DDH). The early onset of debilitating degenerative changes in the hip joint when treatment options are limited remains the biggest fear. Controversy exists regarding the pathophysiology of this disorder, as well as exactly defining and diagnosing this problem. The natural history of AVN in the setting of DDH is very variable. Current practice concentrates primarily on prevention of this disorder, as there are no reliable ways to intervene at an early stage when changes are potentially reversible. Newer techniques using magnetic resonance imaging may have a role in early diagnosis of this condition before irreversible damage has occurred, and allow for interventions that will favorably affect the natural history of AVN. Treatment options for established AVN in DDH concentrate on improving the biomechanics of the proximal femur but unfortunately do not obviate the need for arthrodesis or arthroplasty at a later date.     

Intravenous pamidronate in the treatment of transient osteoporosis of the hip

The aim of this study was to evaluate the efficacy of intravenous pamidronate in patients with transient osteoporosis of the hip (TOH). Thirteen men and three women (mean age 38.3 years, range 30-49) were recruited. The diagnosis was made by means of radiographs, bone scintigraphy, and magnetic resonance imaging (MRI). Pamidronate (45 mg) was intravenously administered three times, once every third day. The outcome measures included a clinical assessment using a pain visual analog scale (VAS; range 0-100), and the WOMAC functional impairment score (FUI; range 0-100). The bone mineral density (BMD) of the total hip and femoral neck was measured using dual-energy X-ray absorptiometry (DXA). Clinical assessments were made before treatment (T(0)) and 1 month later (T(1)), and the densitometric measurements at T(0), and then after 2 (T(2)) and 4 months (T(4)). A further MRI scan was made 3 months after treatment. In comparison to the unaffected side, there was a significant decrease at T(0) in the BMD of both the total hip (median 16.6%, range 8.5%-29.1%, p < 0.00001) and femoral neck (median 22.5%, range 12.0%-34.2%, p < 0.00001). By T(1), both VAS and FUI had decreased significantly (p < 0.00001). By T(2), the total hip and femoral neck BMD had increased by 10.9% (range 2.7%-23.6%, p < 0.00001) and 12.3% (range 7.8%-26.9%, p < 0.00001), respectively, and all patients were asymptomatic. By T(3), the MRI findings had normalized in all patients and, at T(4), there was a further increase in BMD. None of the patients experienced symptom relapse during the follow-up of 39.5 +/- 17.7 months. These results suggest that a short course of pamidronate is effective in treating TOH, and leads to a prompt and long-lasting recovery.     

Avascular necrosis of the hip in multiple epiphyseal dysplasia

We observed radiographic changes of avascular necrosis (AVN) of the capital femoral epiphysis in 9 hips of 11 patients with multiple epiphyseal dysplasia (MED). Plain roentgenography, bone scintigraphy, and magnetic resonance imaging (MRI) studies all revealed characteristic asymmetric changes in the presence of AVN superimposed on dysplastic femoral heads.     

The diagnostic dilemma created by osteoid osteoma that presents as knee pain

Purpose: Osteoid osteoma is a rare benign bone lesion with a high incidence in adolescents and young people. The objective of our study was to illustrate the difficulties in diagnosis of osteoid osteoma in patients presenting with atypical knee pain. Type of Study: Retrospective case series. Methods: In 10 patients who presented to our department with atypical knee pain between 1984 and 1999, the diagnosis of an osteoid osteoma was delayed. Retrospective review of these 10 cases was performed using interviews and re-evaluation of medical histories, radiographs, computed tomography (CT) scans, isotope bone scan, and magnetic resonance imaging (MRI). Results: Initial radiographs showed features of osteiod osteoma in only 2 cases. In addition, in 1 case, not only initial but also repeated radiographs of the knee joint were still normal 10 months after the delineation of the nidus using MRI. Four unnecessary arthroscopies were performed on 4 of the 10 patients and the final diagnosis was established using MRI, CT, and isotope bone scan. The mean time interval between arthroscopy and osteiod osteoma diagnosis was 11.5 months. Conclusions: Osteoid osteoma must be included in the differential diagnosis of persistent unexplained knee pain, especially when objective findings of the knee are vague. The presence of the lesion juxta-articular to the knee joint or in the midshaft or upper end of the femur may be referred as pain to a nearby joint. Plain radiographs have a low diagnostic value in the detection of the lesion whereas isotope bone scan and MRI are reliable imaging techniques. The evaluation of the ipsilateral hip joint should not be overlooked.     

Evaluation of the muscle morphology of the obturator externus and piriformis as the predictors of avascular necrosis of the femoral head in acetabular fractures

Avascular necrosis (AVN) of femoral head is a recognised complication of fracture dislocation of the hip joint but is not studied frequently in relation to acetabulum fractures. The aim was to establish the relationship between obturator externus and piriformis muscle morphology in acetabulum fractures and potenital development of AVN of the femoral head. Twenty-five fractures were included in this prospective study and were subjected to radiological assessment and computed tomography of the pelvis. Magnetic resonance imaging (MRI) of the hip was performed to assess the morphology of obturator externus and piriformis, and findings were compared intraoperatively (in 15 cases). Serial radiographs were taken at monthly intervals to assess the development of avascular necrosis. The patients with no evidence of AVN on radiographs at 6 months had additional MRI scans to look for such changes. Three patients developed AVN of femoral head and two had complete tears of piriformis and/or obturator externus muscles on the pre-operative MRI with the findings confirmed intraoperatively (p = 0.013). None of the patients without changes of AVN at 6-month follow-up had complete tears of either or both muscles. Of these patients, there was one case each of T-type fracture, isolated posterior wall fracture with hip dislocation, and posterior wall with transverse fracture of the acetabulum. Complete tears of obturator externus and/or piriformis muscles are a strong predictor of future development of AVN of the femoral head.     

Association of plasminogen activator inhibitor-1 genotype with avascular osteonecrosis in steroid-treated renal allograft recipients

BACKGROUND: The mechanism of avascular osteonecrosis (AVN) is controversial. Besides an increased bone marrow pressure with reduced blood supply, an enhanced coagulation has been considered. We hypothesize that a genetic variant of the plasminogen activator inhibitor-1 (PAI-1) determines the risk of AVN in glucocorticoid-treated patients. METHODS: Genotyping for the 4G/5G PAI-1 polymorphism was performed in 228 glucocorticoid-treated renal transplant patients. AVN of the hip was present in 26 patients. Magnetic resonance imaging (MRI) of the hips was obtained in 81 of the remaining renal transplant patients without clinical symptoms of AVN. RESULTS: The presence of the homozygous 4G/4G PAI-1 genotype was higher in patients with AVN (60.3%) as compared with patients without either clinical (20.6%, P<0.007) or radiological signs of AVN (17.3%, P<0.002). The prevalence of AVN by genotype was 1.8% with the 5G/5G, 7.7% with the 5G/4G, and 30.3% with the 4G/4G alleles (P<0.001 vs. 5G/4G and 5G/5G). The prevalence of AVN increased with increasing body mass index (BMI) (P=0.04). The prevalence of AVN by genotype in subjects with persistent hyperparathyroidism was 4.2% with the 5G/5G, 15.2% with the 5G/4G, and 55.5% with the 4G/4G alleles (P<0.003 vs. 5G/4G and P<0.001 vs. 5G/5G). CONCLUSIONS: Hypofibrinolysis conferred by the 4G/4G PAI-1 gene variant is a major predisposing factor for AVN in renal transplant patients. The risk is particularly high in obese subjects or patients with persistent hyperparathyroidism. A prospective intervention study of early anticoagulation after renal transplantation is needed to assess whether glucocorticoid-associated AVN can be prevented.     

Avascular necrosis in children with acute lymphoblastic leukemia

This study describes the prevalence and demographics of avascular necrosis (AVN) in children with acute lymphoblastic leukemia (ALL). With improving survival of ALL patients on modern chemotherapy regimens, an increasing number of children with AVN will be presenting to orthopaedists. From 1991 to 1996, 202 patients were treated for ALL at a major tertiary pediatric cancer referral center. Eight patients (4.0%) subsequently developed AVN at an average of 30.0 months after beginning chemotherapy. A total of 27 documented joints were involved, with an average of 3.4 joints affected per patient diagnosed with AVN. The subset of patients with high-risk ALL who underwent an aggressive chemotherapy protocol was particularly susceptible to developing AVN. Six of 58 high-risk ALL patients (10.3%) developed AVN at an average of 18.5 months. As ALL patients now frequently survive into adulthood, orthopaedists will be increasingly called on to manage AVN affecting multiple joints in children and young adults.     

Magnetic resonance imaging of the ischemic hip. Alterations within the osteonecrotic, viable, and reactive zones

To explore the ability of magnetic resonance imaging (MRI) to depict the morphologic features of avascular necrosis (AVN) of the femoral head and to determine whether a classification based on stage of necrosis is possible, images of hips with 56 proved lesions were examined and correlated with roentgenographic stage, severity of pain and functional impairment, and available computed tomography (CT) scans. Six femoral heads with AVN were also studied ex vivo with MRI, CT, roentgenographic, and histologic examinations. These examinations were compared with 100 normal hips in 50 individuals and one normal proximal femoral specimen. The reactive interface between live and dead bone at the periphery of AVN lesions had a characteristic MRI appearance that facilitated diagnosis. Based on central signal intensity on two different pulse sequences, lesions could be separated into four classes that correlated with roentgenographic and clinical staging. Lesions that were isointense with fat on both sequences had an earlier roentgenographic stage and less severe symptoms than did lesions that were less intense than fat. Among hips with AVN in patients younger than 50 years of age, 67% had premature conversion to fatty intertrochanteric marrow outside the borders of the lesion. Detecting premature conversion to fatty marrow has important implications regarding the pathogenesis of AVN and may aid early diagnosis. MRI provides pathophysiologic information that is different from information obtained from conventional methods or various combinations of methods and may provide a basis for an improved system for grading AVN lesions.     

Avascular osteonecrosis after renal transplantation

Avascular osteonecrosis (AVN) is a serious osseous complication after renal transplantation. Its prevalence clearly decreased from 20% to 4% after introduction of cyclosporine and reduction of steroid doses. The aim of our study was to evaluate the frequency of AVN among kidney transplant recipients and to determine the risk factors by comparing them with a population without AVN. Among 326 kidney transplant recipients between June 1986 and December 2004, 15 patients developed AVN with mean age of 40.86 years, including 11 men and 4 women. Fifteen kidney transplant recipients without AVN were selected to be matched for age, gender, and date of transplantation (control group). Cases of symptomatic AVN were diagnosed by hip X-ray, radioisotope bone scan, or magnetic resonance imaging. AVN was diagnosed at a mean of 3.5 years after transplantation (range, 0.5-13 years). The main localization of AVN was the femoral head in 12 cases and the femoral condyle in 3 cases. We studied the following risk factors: the type of donor (cadaver or living donor), the duration on dialysis before transplantation, the cumulative steroid dose, the acute rejection rate, and the posttransplantation weight gain. Statistical analysis showed that the cumulative steroid dose and the acute rejection rate were higher among the AVN group than the control group (P=.04 and P=.058, respectively). The prevalence of AVN in our population is 4.6%, which is probably an underestimate since these were symptomatic cases. The reduction or early withdrawal of steroids remains the only efficient preventive treatment for AVN.     

Chronic Recurrent Multifocal Osteomyelitis of the Hand: A Rare Pediatric Condition

Background: Chronic recurrent multifocal osteomyelitis (CRMO) is a rare autoinflammatory condition characterized by bone pain and swelling, secondary to sterile bone osteolytic lesions. Estimated incidence is 1:1 000 000, with ~2% involving the hand. We present a case series of CRMO of the hand and review the available literature, with the aim of educating and raising awareness of this condition. Methods: A retrospective chart review was conducted for all patients presenting to the institution diagnosed with CRMO involving the hands. Subsequently, a literature review was performed. Results/Case Series: Three cases of CRMO of the hand were identified. Age ranged from 20 months to 6 years, with 1 female. Time from presentation to diagnosis ranged from 3 to 15 months. Two had a single lesion, with the remaining patient having a second lesion on full-body magnetic resonance imaging (MRI). Three lesions involved phalanges, and one involved a metacarpal. Two received antibiotics without improvement prior to diagnosis. After diagnosis of CRMO, two received intravenous pamidronate. They both later showed improvement on MRI. Conclusion: CRMO is a rare disease with scarce literature to guide management. We present a series of CRMO specifically of the hand. The cases educate key stakeholders, raise awareness of the diagnosis, and illustrate challenging aspects of managing these patients. This includes the special functional and anatomical consideration essential in managing cases involving the hand.     

Percutaneous core decompression: A successful method of treatment of Stage I avascular necrosis of the talus

The talus is a bone uncommonly affected by avascular necrosis (AVN) [1]. Factors such as trauma and pre-existing inflammatory arthropathy (particularly with concomitant steroid use) increase the risk of development of AVN.We report a case of resolution of Stage I AVN, diagnosed clinically and on magnetic resonance imaging (MRI), treated successfully by percutaneous core decompression of the talus.An MRI 12 weeks post-operatively showed complete resolution of the appearances of AVN.     

Ganglion cysts of the cruciate ligaments: a series of 31 cases and review of the literature

ABSTRACT: BACKGROUND: A case series for ganglion cyst of the cruciate ligament with MRI findings, clinical presentation, and management options along with review of literature is presented. METHODS: Of 8663 consecutive patients referred for knee MR imaging, 31 were diagnosed with ganglion cysts of the cruciate ligaments, including 21 men and 10 women of ages 12 to 73 years (mean: 37). A review of charts revealed that knee pain was the chief complaint in all cases. Arthroscopic debridement of ganglion cyst was performed in 11 patients. RESULTS: MRI proved to be a valuable tool in diagnosing and deciding management of these cases. All 11 patients who underwent arthroscopic treatment were symptom-free on a minimum follow-of one year. CONCLUSION: Cyst formation associated with cruciate ligament of the knee is an infrequent cause of knee pain. MR imaging was important in confirming the cyst lesions and provided useful information prior to arthroscopy. Arthroscopic debridement of ganglion cyst produced excellent outcome without recurrence. This study describes the pertinent MRI and intraoperative findings of ganglion cyst.