Femoroacetabular impingement: bone marrow oedema associated with fibrocystic change of the femoral head and neck junction

AIM: To describe the association of bone marrow oedema adjacent to areas of fibrocystic change at the femoral head and neck junction in patients with femoroacetabular impingement. MATERIALS AND METHODS: The clinical and imaging findings in six patients with bone marrow oedema adjacent to an area of fibrocystic change at the femoral head and neck junction are presented. There were five males and one female (age range 19-42 years, mean age 34.5 years). Three patients were referred with a clinical suspicion of femoroacetabular impingement, two with suspected osteoid osteoma and one with a clinical diagnosis of sciatica. The volume of bone marrow oedema (grade 1: 0-25%, grade 2: 26-50%, grade 3: 51-75% and grade 4: 76-100% of the femoral neck width), presence of labral and articular cartilage abnormality, joint effusion, and femoral head and neck morphology were recorded. RESULTS: Magnetic resonance imaging (MRI) identified fibrocystic change in the anterolateral aspect of the femoral head and neck junction in all cases (mean size 9 mm, range 5-14 mm, three multilocular and three unilocular cysts). The volume of oedema was variable (one grade 1, two grade 2, one grade 3 and two grade 4). All patients had abnormality of the anterosuperior labrum with five patients demonstrating chondral loss. An abnormal femoral head and neck junction was identified in five patients. CONCLUSION: The radiological finding of fibrocystic change at the anterosuperior femoral neck with or without bone marrow oedema should prompt the search for femoroacetabular impingement. Bone marrow oedema may rarely be identified adjacent to these areas of cystic change and should be considered in the differential diagnosis of bone marrow oedema in the femoral neck.     

Femoroacetabular impingement: the femoral side

Femoroacetabular impingement is an abnormal conflict of the acetabular rim and the femoral head-neck junction. This condition causes labral and cartilage damage and leads to early osteoarthritis of the hip. Femoral osteoplasty is performed to restore normal femoral head-neck offset while the amount of bony resection is monitored by periodic examination. Dynamic examination of the area of impingement, which cannot be performed in open treatment of cam impingement, confirms adequate resection and labral seal through hip range of motion.     

MRI of bone marrow oedema associated with focal bone lesions

AIM: To quantify the volume of bone marrow oedema surrounding focal bone lesions and to identify its relevance relative to diagnosis. METHODS: Three hundred and eighty-eight of 1456 patients included in the orthopaedic oncology database who underwent magnetic resonance imaging (MRI) demonstrated bone marrow oedema and were included in the study. There were 225 males and 163 females, age range 1-87 years (mean 29 years). MRI images were retrospectively reviewed and assessed for the extent of bone marrow oedema. The amount of oedema was graded: grade 1: oedema present but smaller than the lesion size; grade 2: oedema equivalent to the lesion size; grade 3: oedema greater than the lesion size. RESULTS: There were 190 grade 1 lesions: 56% malignant, 33% benign, 11% non-neoplastic; 74 grade 2 lesions: 19% malignant, 50% benign, 31% non-neoplastic; and 124 grade 3 lesions: 10% malignant, 46% benign, 44% non-neoplastic. There was a significant relationship between oedema grade (i.e., volume of oedema) and final diagnosis (p<0.0005). CONCLUSION: Bone marrow oedema may be associated with a wide range of focal bony lesions, including malignant, benign and non-neoplastic causes. As the volume of bone marrow oedema increases relative to the size of the underlying lesion, the probability that the underlying lesion is benign is increased.     

Subperiosteal aneurysmal bone cyst with associated bone marrow oedema: an unusual appearance

A case of a subperiosteal aneurysmal bone cyst with adjacent bone marrow oedema is presented. Aneurysmal bone cysts have been well documented in the published literature; however, relatively few have been observed in a subperiosteal location, and associated bone marrow oedema in the absence of a demonstrable pathological fracture is a rare finding. Aneursymal bone cyst should be considered in the differential diagnosis of subperiosteal bone lesions and may be associated with bone marrow oedema.     

Bone marrow oedema associated with benign and malignant bone tumours

Bone marrow oedema is associated with a wide variety of pathological processes including both benign and malignant bone tumours. This imaging finding in relation to intraosseous tumours can aid in providing a more focused differential diagnosis. In this review, we will discuss the MR imaging of bone marrow oedema surrounding intraosseous neoplasms. The different pulse sequences used in differentiating underlying tumour from surrounding oedema are discussed along with the role of dynamic contrast enhanced MRI. Benign lesions commonly associated with bone marrow oedema include osteoid osteoma, osteoblastoma, chondroblastoma and Langerhan's cell histiocytosis. Metastases and malignant primary bone tumours such as osteosarcoma, Ewing's sarcoma and chondrosarcoma may also be surrounded by bone marrow oedema. The imaging findings of these conditions are reviewed and illustrated. Finally, the importance of bone marrow oedema in assessment of post chemotherapeutic response is addressed.     

Histopathological perspective on bone marrow oedema, reactive bone change and haemorrhage

This article presents a systematic review of the current biomedical literature surrounding the aetiopathogenesis and histopathological features of bone marrow oedema, reactive bone change and haemorrhage. Bone marrow oedema is generally demonstrated as a non-specific finding on magnetic resonance imaging in association with infections, tumours and avascular necrosis. When it occurs in isolation as a primary event not triggered by any obvious bony pathology in the clinical setting of debilitating joint pain, it constitutes the "bone marrow oedema syndrome". Although the latter diagnosis is based on magnetic resonance (MR) imaging, showing the lesion as areas of signal hyperintensity within the marrow, recent radiology-histology correlational studies have shown variably interstitial marrow oedema, necrosis, fibrosis and trabecular bone abnormalities. In light of these facts, the use of the term bone marrow oedema syndrome in a radiological context might be considered questionable, but histopathological techniques are not sensitive in detecting increased extracellular fluid. Reactive bone changes may be focal or diffuse and usually amount to increased bone formation. Bone marrow haemorrhage, due to trauma, results in bone bruising, a condition in which the size of the bruise and associated osteochondral injury determines the outcome, although the natural history of these lesions is still being researched.     

骨髓水肿在股骨头缺血性坏死中的临床意义

目的探讨骨髓水肿（BME）与坏死区信号、关节液体量和临床症状的关系，进一步提高对其在股骨头缺血坏死（ONFH）中临床意义的认识。方法分析经病理或临床随访证实的57例91髋成人ONFH资料。全部病例摄有骨盆正位平片，并于1周内行双髋1．5TMR检查和放射性核素骨显像。分别对股骨头皮质完整组、皮质断裂塌陷组和MRI不同信号坏死区组中的BME进行研究。结果具有“线样征”的88髋中，61髋其远侧区可见BME信号。BME在皮质完整的混杂信号坏死组中的出现率高于皮质完整的单纯脂肪样信号坏死组，而低于皮质断裂塌陷组（P〈0．05）。皮质断裂塌陷中的关节液体量和临床症状出现率与皮质完整中有BME组相当（P〉0．05），均大于皮质完整无BME组（P〈0．01）。结论临床无症状患者大多无BME，而无BME且股骨头皮质完整的髋关节内多见少量液体。伴有BME的患者无论股骨头皮质是否断裂塌陷，髋关节内常见大量液体，临床大多具有症状。ONFH中出现BME或BME程度加重时，提示病情进展。     

兔创伤性股骨颈骨折后股骨头血流的改变及其意义

目的采用三相~~(99)Tcm-亚甲基二磷酸盐(MDP)骨显像评价创伤性股骨颈骨折后各时期股骨头血流灌注的变化。方法24只左侧股骨颈骨折的新西兰大白兔,分别与骨折前、骨折后即刻、1,3个月行三相骨显像,评价股骨头血流改变,计算左右两侧放射性计数比(头-头比)。结果骨折前双侧股骨头血流分布对称,左右头头比为1.01±0.04,骨折后即刻、1,3个月左侧股骨头血流灌注表现为正常、低血供、高血供倾向,静态相左右头-头比分别为1.08±0.36,0.83±0.26,3.68±0.21。结论创伤性股骨颈骨折后即刻,供应股骨头血流的血管可能并未受到损伤,早期或后期的继发性因素致使血管损伤、股骨头的血供和代谢受到影响;骨折造成血管直接损伤机制可能并非创伤性股骨颈骨折后股骨头坏死的主要原因,可能还存在其他的多种机制。     

Focal bone tracer uptake associated with a herniation pit of the femoral neck

The herniation pit of the femoral neck is a common radiographic lesion whose pathogenesis has been described by Pitt et al and reported as negative on bone scanning. This case report demonstrates increased uptake of Tc-99m MDP in a herniation pit of the femoral neck.     

Bone marrow oedema on MR imaging indicates ARCO stage 3 disease in patients with AVN of the femoral head

Objectives

To test the hypothesis that bone marrow oedema (BME) observed on MRI in patients with avascular necrosis (AVN) of the femoral head represents an indicator of subchondral fracture.

Methods

Thirty-seven symptomatic hips of 27 consecutive patients (53 % women, mean age 49.2) with AVN of the femoral head and associated BME on magnetic resonance (MR) imaging were included. MR findings were correlated with computed tomography (CT) of the hip and confirmed by histopathological examination of the resected femoral head. Imaging studies were analysed by two radiologists with use of the ARCO classification.

Results

On MR imaging a fracture line could be identified in 19/37 (51 %) cases, which were classified as ARCO stage 3 (n?=?15) and stage 4 (n?=?4). The remaining 18/37 (49 %) cases were classified as ARCO stage 2. However, in all 37/37 (100 %) cases a subchondral fracture was identified on CT, indicating ARCO stage 3/4 disease. The extent of subchondral fractures and the femoral head collapse was graded higher on CT as compared to MRI (P?Histopathological analysis confirmed bone necrosis and subchondral fractures.

Conclusions

In patients with AVN, BME of the femoral head represents a secondary sign of subchondral fracture and thus indicates ARCO stage 3 disease.

Key Points

? BME on MRI in AVN of femoral head indicates a subchondral fracture. ? BME in AVN of the femoral head represents ARCO stage 3/4 disease. ? CT identifies subchondral fractures and femoral head collapse better than MR imaging. ? This knowledge helps to avoid understaging and to trigger adequate treatment.     

股骨头坏死骨髓水肿研究进展

<正>股骨头坏死(osteonecrosis of femoral head,ONFH)是一种骨科临床常见疾病,目前其病因病机尚不清楚,且致残率高,现已成为骨科疑难病种之一。在MRI出现之前,对股骨头坏死的诊断主要以X线片、CT及ECT为主,这些诊断方式各有优势     

Fibrocystic changes at anterosuperior femoral neck: prevalence in hips with femoroacetabular impingement

PURPOSE: To retrospectively evaluate if there is an association between juxta-articular fibrocystic changes at the anterosuperior femoral neck and femoroacetabular impingement (FAI). MATERIALS AND METHODS: The institutional review board approved this study and did not require informed patient consent. An orthopedic surgeon and a radiologist in consensus retrospectively reviewed the anteroposterior (AP) pelvic radiographs of 117 hips with FAI and compared these images with the AP radiographs of a control group of 132 hips with developmental dysplasia (DD) to determine the prevalence of juxta-articular fibrocystic changes at the anterosuperior femoral neck. Criteria for juxta-articular fibrocystic changes at the anterosuperior femoral neck were location close to the physis and a diameter (of the fibrocystic change) of greater than 3 mm. The sensitivity and specificity of AP pelvic radiography in the detection of these fibrocystic changes were calculated by using an additional 61 hips with FAI and on the basis of findings at magnetic resonance (MR) arthrography, which was routinely performed for assessment of FAI. In 24 patients who underwent joint-preserving surgery for FAI, the fibrocystic changes were localized intraoperatively and the spatial relation of the region of these changes to the area of FAI was identified. Joint-preserving surgery consisted of anterior surgical dislocation of the hip with osteochondroplasty of the proximal femur and/or the acetabular rim to improve the impingement-free range of hip motion. For statistical comparisons, nonparametric tests were performed. RESULTS: Fibrocystic changes were identified on the AP radiographs of 39 (33%) of the 117 FAI-affected hips and on none of the radiographs of the 132 DD-affected hips. According to MR arthrogram findings, the sensitivity, specificity, and positive and negative predictive values of AP pelvic radiography were 64%, 93%, 91%, and 71%, respectively. The mean diameter of the juxta-articular fibrocystic changes was 5 mm (range, 3-15 mm); smaller lesions were more prevalent. Dynamic MR imaging with the hip flexed and intraoperative observations revealed a close spatial relationship between the region of the fibrocystic changes at the anterosuperior femoral neck and the acetabular rim. CONCLUSION: The high prevalence of juxta-articular fibrocystic changes at the anterosuperior femoral neck and their spatial relation to the impingement site suggest an association and possible causal relationship between these alterations and FAI.     

Osteonecrosis of the femoral head extending into the femoral neck

Osteonecrosis of the femoral head (ONFH) is an ischemic disorder that can lead to femoral head collapse and secondary osteoarthritis. Although the condition is usually limited to the femoral head, we report a rare case of biopsy-proven ONFH extending into the femoral neck, which required hip replacement surgery. We emphasize the imaging features of this condition and briefly discuss its potential relevance.     

Correlation between bone marrow edema and collapse of the femoral head in steroid-induced osteonecrosis

OBJECTIVE: The purpose of this study was to clarify whether bone marrow edema is detectable on initial MR imaging of steroid-induced osteonecrosis of the femoral head. SUBJECTS AND METHODS: Forty-eight hips with osteonecrosis were examined consecutively with MR imaging and radiography. In a previously reported screening program, osteonecrosis was diagnosed on MR imaging when subchondral bands of abnormal signals were present. In the screening program, the MR images of 200 hips of 100 patients receiving high-dose steroid therapy were examined prospectively. Subchondral bands were detected in 48 hips at a mean of 14 weeks after the initiation of steroid therapy. RESULTS: On follow-up MR imaging of 47 hips (one hip excluded) bone marrow edema was initially observed in 13 hips after the onset of hip pain. MR imaging of the remaining 34 hips did not reveal bone marrow edema and the patients were all asymptomatic. MR imaging of 31 of the 34 hips continued to show subchondral bands and MR imaging of the other three hips indicated that the subchondral bands had disappeared. When bone marrow edema was detectable, abnormal findings on radiography were slight but 11 (85%) of the 13 hips progressed to advanced osteonecrosis. Bone marrow edema was highly correlated with the subsequent collapse of the femoral head (p<0.0001). CONCLUSION: Bone marrow edema was not present on initial MR imaging of osteonecrosis. Bone marrow edema should be considered a marker for potential progression to advanced osteonecrosis, and careful examinations for osteonecrosis are necessary when bone marrow edema is seen.     

用带蒂骨瓣加骨髓移植治疗青壮年股骨颈头下型骨折

目的观察带蒂骨瓣加骨髓移植治疗青壮年股骨颈头下型骨折的效果。方法从1994年1月～2001年12月,对37例股骨颈头下型骨折采用带缝匠肌蒂髂骨瓣结合红骨髓移植治疗,同时应用2根空心加压螺纹钉内固定。结果术后随访2～5年,34例在术后6个月～1年全部骨折愈合,未发现股骨头坏死,优良率达91．9％。3例因过早弃拐负重,导致股骨头坏死。结论采用内固定及带血运皮质骨块植骨与植入红骨髓的方法,可以促进股骨颈头下型骨折早期愈合,防止股骨头坏死。     

成人股骨头缺血性坏死合并骨髓水肿的介入治疗

目的探讨成人股骨头缺血性坏死合并骨髓水肿的介入治疗及其疗效观察。方法选择临床症状突出,经磁共振成像（MRI）检查证实的成人股骨头缺血性坏死合并骨髓水肿的患者20例,24髋,经对侧股动脉插管,分别超选择至患侧旋股内、外动脉,闭孔动脉开口,造影确定导管位置后,灌注溶栓剂、解痉剂及血管扩张剂等。结果①经2次或3次介入灌注术后与灌注前造影片对比,股骨头颈部血管增多、增粗、股骨头染色变深16例22髋,2例2髋改变不明显。②本组20例中有19例患者疼痛消失、明显减轻或缓解,总有效率占95％。③24个髋关节介入治疗前后活动范围均有不同程度改善。④16髋介入治疗后MRI对比,骨髓水肿明显减轻。结论介入灌注术治疗股骨头缺血性坏死合并骨髓水肿疗效确切。     

双极股骨头置换治疗高龄股骨颈移位骨折21例

笔者于2004-06至2009—10对21例高龄患者采用后外侧手术入路行双极股骨头置换,股骨颈移位骨折疗效满意。     

双极人工股骨头置换治疗高龄股骨颈骨折的疗效分析

目的探讨高龄股骨颈骨折应用双极人工股骨头置换的临床疗效。方法对63例高龄股骨颈骨折患者行骨水泥固定的国产双极人工股骨头置换,术后根据Harris评分法和X线资料评定其疗效。结果本组63例均成功完成手术,术中无血管神经损伤。术后无切口感染和关节脱位,无围术期死亡。术后随访10～42(15.3±2.1)个月。术后合并肺部感染6例,泌尿系感染5例,下肢深静脉血栓形成3例,中枢神经系统功能障碍2例,脑梗死1例。X线片检查显示髋关节间隙变窄11例,假体轻度内翻5例,出现假体下沉3例,骨水泥周围<2 mm的透亮带2例。根据Harris评分法评定,优22例,良26例,中12例,差3例,优良率76.19%。结论应用骨水泥固定的双极股骨头置换治疗高龄股骨颈骨折疗效满意。