The transitory bone marrow edema syndrome of the hip

AIM OF THE STUDY: Since MRI-studies had begun to establish the diagnosis of transitory bone marrow edema syndrome of the hip orthopedic surgeons have tried to integrate this new syndrome into the internationally accepted system of musculoskeletal diseases. Particularly, the relation to non-traumatic osteonecrosis of the femoral head and the possibilities in therapy were investigated in our clinical trial. METHODS: Our clinical trial encompassed 106 patients suffering from the transitory bone marrow edema syndrome diagnosed in our department between the years 1985 and 2000. In order to confirm this diagnosis we used the patients' histories, their clinical courses, MRI studies, scintigraphic bone scans, intraosseal pressure measurements, phlebographies, laboratory data, and histologic specimens. One half of our collective positive for transient bone marrow edema of the hip underwent core-decompression surgery (50 patients), the other half (56 patients) was treated conservatively by analgesic medication combined with restriction of weight-bearing in the affected extremity. RESULTS: Patients positive for transitory bone marrow edema syndrome of the hip are middle-aged individuals with a male to female predominance of 60 : 40. This group has no or only few risk factors usually associated with osteonecrosis of the femoral head. Thus, the missing alcoholic abuse is striking. All patients suffering from transitory bone marrow edema syndrome of the hip recovered completely independent of the therapy we initiated and none of them showed any signs of osteonecrosis. The one half undergoing surgical decompression of the edema by using a 4.5 mm drill experienced an markedly accelerated relief of their clinical symptoms as well as their signal changes on MRI studies. Conventional X-ray pictures and scintigraphic bone scans are not useful for early differentiation between early stages of osteonecrosis and bone marrow edemas. This also accounts for the historical measurements of intraosseal pressure determinations and phlebographies. In contrast to that, MRI studies are effective in early differentiation between osteonecrosis and bone marrow edema syndrome of the hip, especially when contrast medium (gadolinium) is administrated intravenously and fat-suppressed MRI-sequences find use. Beginning osteonecrosis of the femoral head shows a segmental loss of contrast medium, a "double line sign" interface to the intact bone marrow, and only in a few cases they are associated with a huge symptomatic edema. The histologic examination of specimens obtained from 43 patients with transitory bone marrow edema syndrome of the hip revealed no signs of osteonecrosis. CONCLUSION: MRI studies are useful in differentiation between bone marrow edema syndrome of the hip and non-traumatic osteonecrosis of the femoral head in each stage of these two diseases. The thorough differentiation between these two diseases is of extraordinary importance for the clinical work-up of the patients as well as for scientific reasons. The course of primary bone marrow edema is benign as it results in entire recovery. The core decompression surgery offers the chance to shorten the course of the disease.     

Fatty marrow conversion of the proximal femoral metaphysis in transient bone marrow edema syndrome

Introduction In the proximal femoral metaphysis, hematopoietic marrow is predominant during the adult stage of life. The conversion of hematopoietic marrow to fatty marrow in the proximal femoral metaphysis has been suggested as an etiologic factor of ischemia in the pathogenesis of femoral head osteonecrosis. To determine whether the chronology of fatty marrow conversion of the proximal femoral metaphysis is related to transient bone marrow edema syndrome of the hip, a case control study was conducted on 10 patients with the disease.Materials and methods There were 8 men and 2 women with a mean age of 33 years (range 19–45 years). The 10 patients were matched with 20 controls for gender and age (5-year range). T1-weighted MRI scans of their hips were reviewed. Marrow of the greater trochanter becomes fatty before puberty, and thus, the greater trochanter can be used as a built-in control. The signal intensity of the proximal femoral metaphysis was compared to that of the greater trochanter.Results In all patients, the signal intensity of the proximal femoral metaphysis was isointense (fatty marrow) relative to that of the greater trochanter. In control subjects, the signal intensity was isointense in 8 (40%) and hypointense (hematopoietic marrow) in 12 (60%) (p<0.05).Conclusion The current study shows that the proximal femoral metaphysis is predominantly fatty in transient bone marrow edema syndrome. The conversion of hematopoietic to fatty marrow is known to correlate with decreases in intramedullary blood flow. Thus, the current study suggests that an ischemia of the proximal femur secondary to fatty marrow conversion of the proximal femoral metaphysis might be a cause of transient bone marrow edema syndrome of the hip.     

Magnetic resonance imaging in diagnosis of transient osteoporosis of the hip.

The results of magnetic resonance (MR) imaging in six patients with transient osteoporosis of the hip were reviewed. Short TR/TE (repetition time/echo time) images demonstrated diffusely decreased signal intensity in the femoral head and intracapsular region of the femoral neck. Increased signal intensity was noted with progressive T2 weighting. Bone biopsies were performed in four patients. Histologic findings were nonspecific and included fat necrosis, marrow edema, increased bone resorption, and reactive bone formation. Repeat MR scans in two patients, performed six and eight months after the initial scans, showed an almost complete return to normal marrow signal. All patients became asymptomatic without bony deformity. In the appropriate clinical setting, MR scanning can aid in the diagnosis of transient osteoporosis as the cause of a painful hip.     

髓芯减压联合高压氧治疗髋关节骨髓水肿综合征

目的探讨髓芯减压联合高压氧治疗髋关节骨髓水肿综合征（BMES）的疗效。方法髓芯减压联合高压氧治疗12例髋关节BMES患者。结果12例均获随访,时间6～24个月。患者疼痛均完全消失,术后4～12周髋关节功能恢复正常。随访期间未发现病情复发及股骨头坏死。结论髓芯减压联合高压氧治疗髋关节BMES,创伤小,并发症少,疗效好。     

Migrating bone marrow edema syndrome: a cause of recurring knee pain

Bone marrow edema syndrome is a condition of unknown etiology, presenting with painful limping. It is characterized by normal radiographs, but magnetic resonance imaging findings change with bone marrow edema. When there is osteopenia in the radiographs, the condition is called transient osteoporosis. The term migratory bone marrow edema syndrome is used when there is involvement of another joint, or another compartment in the same joint, which typically occurs within 6 months of onset of primary symptoms. Here, a case of migratory bone marrow edema syndrome in a 47-year-old male patient, which was conservatively managed, is reported.     

骨髓水肿综合征与股骨头缺血性坏死

目的探讨骨髓水肿综合征(bone marrow edema syndrome,BMES)与股骨头缺血性坏死(avascular necrosis of femoral head,ANFH)的差异。方法广泛查阅国内外关于ANFH及BMES研究的相关文献,进行回顾及综合分析。结果 BMES与ANFH在病理、发病机制、临床表现、治疗方法及预后等方面存在不同。结论 BMES与ANFH是两种不同性质的疾病,微骨折可能是骨髓水肿出现的原因。     

Biochemical markers of bone metabolism in bone marrow edema syndrome of the hip

The aim of this study was to evaluate bone metabolism in patients with bone marrow edema syndrome of the hip. In 37 consecutive patients undergoing core decompression of the femoral head, biochemical markers of bone metabolism were measured in aspirates from cancellous bone and in samples obtained simultaneously from peripheral blood. The diagnosis was made by means of radiographs, magnetic resonance imaging (MRI), and core biopsy specimens. Undecalcified microtome section were available for histopathological evaluation. Bone specific alkaline phosphatase (bone ALP), osteocalcin (OC), procollagen Type I N-terminal propeptide (PINP), and C-terminal cross-linking telopeptide (ICTP) were studied. Mean serum levels of analytes were 13.1 ng/mL (OC), 11.2 ng/mL (bone ALP), 4.7 ng/mL (ICTP), and 38.8 ng/mL (PINP). In samples obtained from cancellous bone, mean concentrations of all markers were elevated significantly. The mean bone to serum ratios for bone ALP and OC were 14.1 (P=0.005) and 4.1 (P=0.002), respectively. For collagen Type I metabolites, bone to serum ratios averaged 16.3 (P=0.001) for ICTP and 9.6 (P=0.001) for PINP. Markers of bone formation correlated with each other in serum as well as in aspirates from cancellous bone. Elevation of all markers in aspirates from cancellous bone pointed at increased bone turnover, which correlated with histopathological findings of irregularly woven bone, osteoid seams, and lining cells. Mean serum concentrations of all markers, however, were not different from healthy individuals and thus did not provide any useful clue in the diagnosis of this disease. The lack of osteonecrotic regions in our specimens, the marked increase of bone turnover in samples obtained from edematous lesions, and the fact that none of the patients developed osteonecrosis of the femoral head so far seem to further support the contention that transient bone marrow edema syndrome of the hip is a distinct clinical entity.     

Three cases of regional migratory osteoporosis

We examined three patients with regional migratory osteoporosis. Radionucleotide bone scanning and MRI was helpful in the diagnosis of this disease, and all patients recovered with conservative treatment. A biopsy of the femoral head, which was performed in one case, demonstrated bone marrow edema without osteonecrosis. A low intensity area of subchondral bone was observed on a T1-weighted image in two cases, as well as a fracture of the subchondral bone, which might be associated with transient osteoporosis. In one case, the affected region migrated from the medial femoral condyle to the lateral femoral condyle in the same knee joint.     

股骨上端骨髓水肿综合征的MRI表现特点

目的：分析股骨上端骨髓水肿综合征的MRI表现特点以提高对该病的认识。方法;回顾性分析10例股骨上端骨髓水肿综合征患者的MRI表现,男6例,女4例;年龄36～57岁,平均41．5岁;病史1周～3个月。临床表现为突然发作的髋部疼痛9例,行走能力及髋关节活动受限7例;全部病例无明显外伤史,女性患者未在孕期。随访3～12个月,症状消失3个月复查MRI后结束随访。结果：MRI主要表现为弥漫性骨髓水肿,累及股骨头、颈、粗隆间,10例13髋中骨髓水肿1级6髋,2级5髋,3级2髋。合并髋关节积液9髋,I级积液6髋,Ⅱ级1髋,III级2髋。治疗3-12个月后患者髋部疼痛症状消失,股骨内MRI信号恢复正常。     

Bone marrow edema syndrome associated with uterine myoma: a case report

A patient with bone marrow edema syndrome of the hip associated with a uterine myoma is presented. A 51-year-old woman could not walk because of severe pain in both hips and had been referred to the authors' institute. Magnetic resonance imaging scans showed abnormal intensity on T1- and T2-weighted images in both femoral heads and a large mass arising from the uterus which was diagnosed as a uterine myoma. A 99mTc-methylene diphosphonate scintigraph showed diffuse uptake in both femoral heads. The pain in both hips decreased shortly after a hysterectomy and the patient could walk without crutches within 2 weeks after the gynecologic surgery. Magnetic resonance imaging scans taken 8 months after surgery showed high signal intensity on T1- and T2-weighted images, indicating normal bone marrow in the femoral heads. To the authors' knowledge, this is the first case report showing a bone marrow edema syndrome of the hip associated with uterine myoma. The pathophysiologic mechanisms for bone marrow edema syndrome of the hip in the current patient and in pregnancy may be identical. More specifically, a large intrapelvic mass may cause an increase of intrapelvic pressure and subsequent blood stasis in both conditions. The current case suggests the possible factors of bone marrow edema syndrome of the hip which need to be investigated.     

Compromised Bone Marrow Perfusion in Osteoporosis

A link between bone blood flow and osteoporosis may exist. Outside of the spine, the proximal femur is the most common site of osteoporotic fracture and is also an area prone to avascular necrosis and fracture nonunion. This study of the proximal femur investigates the relationship between BMD, bone marrow fat content, bone perfusion, and muscle perfusion. One hundred twenty healthy female subjects (mean age, 74 yr; age range, 67–89 yr) underwent DXA examination of the hip, proton MR spectroscopy, and dynamic contrast‐enhanced MR imaging of the right proximal femur, acetabulum, and adductor thigh muscle. In all bone areas examined (femoral head, femoral neck, femoral shaft, acetabulum), perfusion indices (maximum enhancement, enhancement slope) were significantly reduced in subjects with osteoporosis compared with subjects with osteopenia or normal BMD. Adductor muscle perfusion was not affected by change in BMD. As marrow perfusion decreased in the proximal femur, marrow fat increased (r = 0.827). This increase in fat content seemed to account for the decrease in marrow perfusion more than a reduction in BMD. For normal BMD subjects, perfusion parameters in the femoral head were one third of those in the femoral neck or shaft and one fifth of those in the acetabulum. Perfusion throughout the proximal femur is reduced in osteoporotic subjects compared with osteopenic and normal subjects. This reduction in perfusion only affects bone and not those tissues outside of bone with the same blood supply. As bone perfusion decreased, there was a corresponding increase in marrow fat.     

8例髋关节暂时性骨质疏松症的临床诊断与治疗

目的探讨髋关节暂时性骨质疏松症（transient osteoporosis of the hip,TOH）的临床表现、诊断、鉴别诊断、治疗及预后。方法2003年8月至2009年8月治疗8例TOH患者,男2例,女6例;年龄22—43岁,平均34．9岁。患者均为单侧发病,左侧5例,右侧3例。患者的患髋均表现有不同程度的突发急性疼痛或渐进性疼痛,同时伴有显著的跛行。患髋内旋轻度受限是主要的体征。症状出现后3—6周,x线片可见股骨头均匀广泛的骨质疏松,MR表现为弥散且一致的等低T1、长T2异常信号,脂肪抑制序列呈高信号。嘱患者在疼痛可忍受的条件下半负重行走,避免出现骨折等并发症;口服二膦酸盐和钙剂;剧烈疼痛时,可口服非甾体类抗炎药物缓解疼痛。结果临床治疗3个月后疼痛明显减轻,10个月后疼痛完全缓解,复查MR示病变完全消失。结论TOH是一种少见的疾病,无原因出现的髋关节疼痛和跛行是主要症状,X线片和MR可分别看到暂时性的骨质疏松和骨髓水肿。此病具有自限性,保守治疗可获得良好的结果,明确诊断是治疗的关键。     

股骨头骨髓水肿综合征的诊治及其与股骨头缺血性坏死的鉴别诊断

目的：通过对股骨头骨髓水肿综合征诊治的观察,分析其疾病特点及其与股骨头缺血性坏死的异同。方法：自2004年1月,股骨头骨髓水肿综合征患者19例,男12例,女7例;平均年龄（46．7±10．36）岁。给予药物及物理治疗,治疗前后按照髋关节Harris评分系统进行评分。结果：治疗前平均（43．17±12．62）分,治疗后平均（86．73±14．29）分,治疗前、后评分差异有统计学意义（P〈0．05）。结论：股骨头骨髓水肿综合征疾病特点不同于股骨头缺血性坏死,是一类独立的疾病。     

Value of a dynamic MR scan in predicting vascular ingrowth from free vascularized scapular transplant used for treatment of avascular femoral head necrosis

We have treated three patients with avascular osteonecrosis using vascularized scapular bone graft. To predict blood perfusion in both the diseased femoral head and the transferred bone, all the hips were followed up using dynamic magnetic resonance (MR) scans, performed 1 and 7 months after surgery. In the present cases, it was shown that conventional enhanced MR imaging sometimes depicts increased intensity in bone marrow without blood perfusion due to the leakage of gadolinium-DTPA (Gd-DTPA) from the capillaries surrounding the avascular tissue. It was found that Gd-DTPA remaining in the dead bone marrow resulted in a false-positive image. By contrast, the dynamic MR scan evaluated only those images taken before the leakage. This is one of the advantages of the dynamic study, which reflects actual blood flow in the bone. The fast rise in the time-intensity curve following bolus injection of Gd-DTPA indicates that there is fast blood perfusion in the bone. The dynamic MR scan has demonstrated that there is little blood perfusion in the diseased bone 1 month after the operation and that vascular ingrowth from the transferred bone flap proceeds gradually between 1 and 7 months after surgery. These findings indicate that the dynamic MR scan is very useful in demonstrating vascular ingrowth after surgery in avascular necrosis of the femoral head and can be a reliable monitoring technique for anastomotic patency of the vascularized bone flap. © 1995 Wiley-Liss, Inc.     

Bilateral Transient Osteoporosis of the Hip in a Young Man

Transient osteoporosis of the hip (TOH) is a rare disorder of unknown cause that is characterized by diffuse bone marrow edema of the femoral neck and head. A case of bilateral TOH occurring in a 32-yr-old man is reported and the radiological findings and bone densitometry that illustrate the natural history of this disorder are presented. The management of this disorder including the possible indications for antiresorptive therapy is reviewed.     

股骨头坏死修复反应区的骨髓水肿及其病理改变

目的探讨股骨头坏死修复反应区骨髓水肿的病理基础和临床意义。方法随机取20个因股骨头坏死行全髋关节置换的股骨头标本，取修复反应区制作成病理切片。根据MRI脂抑像表现分为骨髓水肿组和非水肿组。将两组病理切片的显微镜下结构随机取5个视野，对于所见坏死和崩解骨组织、脂肪组织、造血组织、肉芽组织、纤维组织，进行比较。结果本研究显示骨髓水肿组肉芽组织明显较常见（x^2=13．107，P〈0．05），而无水肿组脂肪组织（x^2=17．755，P〈0．05）和造血组织（x^2=2．838，P〈0．05）较多，两组差异有统计学意义。而坏死骨小梁（x^2=0．457，P〉0．05）、崩解组织（x^2=0．037，P〉0．05）、纤维组织（x^2=0．428，P〉0.05）在两组分布相似，差异无统计学意义。结论股骨头坏死修复反应区的骨髓水肿是一种炎性反应表现，其产生机制可能与股骨头内微骨折有关，对于临床治疗的相关性尚需进一步研究。     

Transient epiphyseal lesion of the femoral head after traumatic hip dislocation: A case report

IntroductionWe experienced a rare case in which magnetic resonance imaging (MRI) showed a transient epiphyseal lesion of the femoral head four months after traumatic hip dislocation. To our knowledge, there have been no previously published reports on the development of such transient lesions after traumatic hip dislocation involving no abnormalities just after dislocation.Presentation of caseWe report a 22-year-old man who showed a transient epiphyseal lesion of the femoral head after traumatic hip dislocation. On MRI performed two days after dislocation, no bony injuries were observed around the hip joint. Four months after dislocation, the patient suddenly experienced right hip pain without any new trauma or injury. A low-intensity band convex to the articular surface was apparent above the epiphyseal scar on T1-weighted imaging, and bone marrow edema was observed around the band lesion on short-tau inversion recovery imaging. Following a two-month period of non-surgical conservative therapy, the patient’s hip pain resolved and the low-intensity band was no longer observed on follow-up MRI.DiscussionAlthough the detailed pathogenesis of this transient changes was unclear, we speculate that prolonged rest after traumatic hip dislocation may contribute to bone insufficiency, resulting in an insufficiency fracture of the femoral head.ConclusionThis study suggests that transient epiphyseal lesions of the femoral head may occur in patients with a history of traumatic hip dislocation associated with an adapted long-term rest.     

Magnetic resonance imaging and histology of repair in femoral head osteonecrosis

Different repair processes affect the clinical course of nontraumatic avascular femoral head osteonecrosis, not just necrotic lesion size and location. Fourteen femoral heads were retrieved at total hip arthroplasty after core decompression treatment, or after conservative treatment was done on 13 male patients diagnosed with different stages of femoral head osteonecrosis. To determine repair types, features of coronal magnetic resonance images were correlated with light microscopy findings on corresponding coronal undecalcified sections and microradiographs of the retrieved femoral heads. In five femoral heads, repair of necrotic bone and marrow remained restricted to the reactive interface for as many as 63 months, producing the diagnostic osteosclerotic rim with adjacent hypervascularity (limited repair). Nine femoral heads showed extension of the repair process into the necrosis. In five femoral heads, predominant resorption of necrotic bone led to femoral head breakdown within 2 to 50 months (destructive repair). In four femoral heads, reparative bone formation had started from subchondral fractures and/or the reactive interface, definitely reducing the size of the necrotic area (reconstructive repair). In the latter, the disease progressed slowly or stopped for as many as 45 months, irrespective of treatments, but elimination of risk factors seemed beneficial. Although core decompression did not always reach the necrotic area and improve repair, it reduced accompanying bone marrow edema and could delay the disease progress. Osteonecrosis with limited repair can be identified on magnetic resonance images obtained at followup, but the similar signal changes of destructive and reconstructive repair cannot be distinguished on magnetic resonance images alone. The evidence of reconstructive repair in nontraumatic osteonecrosis, however, gives hope for treatments that can improve repair to a sufficient creeping substitution of the affected femoral head.     

Fractional necrosis of the femoral head epiphysis after transient increase in joint pressure. An experimental study in juvenile rabbits

Ischaemia resulting from increased joint pressure may play a role in the pathogenesis of necrosis of the femoral head epiphysis. We studied the effect of temporary vascular occlusion on this epiphysis in young rabbits. Occlusion for six hours resulted in necrosis of trabecular bone and of intertrabecular marrow and vascular tissue, later followed by revascularisation and repair, as has been demonstrated previously. In contrast, raised intra-articular pressure lasting for only two hours resulted in a more complex picture: trabecular osteocytes were dead, whereas the bone-forming marrow was shown by fluorochrome labelling to remain viable, and to form appositional repair bone throughout the epiphysis. We concluded that transient vascular occlusion may cause the death of trabeculae despite intact perfusion of the bone. This type of change may be important in the pathogenesis of Perthes' disease.