Radiology of postnatal skeletal development

The patella initially ossifies at between three and five years, commencing as multiple foci that rapidly coalesce. As the patellar ossification center enlarges the expanding margins may be irregular and associated with accessory ossification centers. These are most common superolaterally and may lead to the development of a bipartite patella. The bipartite patella has cartilaginous continuity despite the appearance of osseous discontinuity. The patella expands to all cartilaginous contours during late adolescence when the epiphyseal ossification centers around the knee are also in the final stages of maturation. The only cartilage not replaced is that occupying the superior twothirds of the articular surface (the lower one-third is covered by the fat pad). The subchondral plate does not assume the actual articular contours until the late stages of osseous maturation (after ten to twelve years). Accordingly, typical measurements such as medial and lateral angulation cannot be accurately done prior to the final stages of patellar ossification expansion and maturation.The tibial tuberosity begins ossification at between seven and nine years as a distal focus. This progressively enlarges proximally and anteriorly, while the main tibial ossification center concomitantly expands downward into the tuberosity. A section of epiphyseal cartilage usually remains between these two ossification centers until close to physeal maturity. The anterior chondro-osseous region at the site of patellar tendon attachment is a biomechanically susceptible region that may be acutely or chronically traumatized to create an Osgood-Schlatter lesion. The physis associated with the tibial tuberosity is histologically modified in a proximal to distal gradation of columnar adaptation to specific biomechanical demands in this region. Closure of the tuberosity physis occurs in a proximal to distal direction.     

MR imaging of the knee. Part II. Chronic disorders

Sixty patients with symptoms of chronic disease of the knee joint were evaluated with high-resolution, thin-section magnetic resonance (MR) imaging. MR imaging depicted a wide variety of knee joint abnormalities including osteochondritis dissecans, medullary infarcts, epiphyseal osteonecrosis, intraarticular osteochondral fragments, synovial cysts, joint effusions, intraarticular soft-tissue tumors, synovial disease, leukemic infiltration of bone marrow, Osgood-Schlatter disease, and nonossifying fibroma. In two cases MR imaging depicted bone infarcts not seen on both radionuclide bone scans and standard radiographs. The highly detailed depiction of the articular cartilage was of particular importance in predicting arthroscopic findings in cases of osteochondritis dissecans. In two cases, a soft-tissue mass (pigmented villonodular synovitis) and a large osteochondral fragment undetected at arthroscopy were accurately localized with MR imaging. The results indicate that MR imaging is capable of providing information that might otherwise require multiple, sometimes invasive diagnostic procedures.     

Osgood-Schlatter Disease in youth elite football: Minimal time-loss and no association with clinical and ultrasonographic factors

BackgroundOsgood-Schlatter Disease is the most common cause of knee pain in youth. Scientific research in youth elite football is limited.ObjectivesTo assess clinical and ultrasonographic factors associated with Osgood-Schlatter Disease and calculate point prevalence of clinical diagnosis and time-loss in youth elite male football.Study designNested case-control study and cross-sectional prevalence study; Level of evidence: 3.MethodsWe obtained data during the pre-season periodic health evaluation. Osgood-Schlatter Disease diagnosis was defined as (1) athlete-reported anterior knee pain and (2) clinical confirmation by pain provocation at the tibial tuberosity. Time-loss was defined as inability to participate in team training and/or competition.For the nested-case control study, we examined clinical and ultrasonographic factors in the U13 to U16 teams. We matched on calendar-age. The clinical factors were: self-reported history of Sever's disease, growth measures, leg muscles flexibility and strength and ultrasonographic bone maturity stages according to Ehrenborg, For the cross-sectional study, we included players of the U13 to U19 teams to calculate the point prevalence.ResultsThe case-control study consisted 30 players and the cross-sectional study 127 players. Previous Sever's disease was strongly associated with Osgood-Schlatter Disease (OR = 16.8; p = 0.02; 95% CI = 1.6–174.5). None of the other clinical or ultrasonographic factors were associated. The point prevalence was 17% and 80% had no time-loss despite presence of clinical symptoms.ConclusionConsidering the 16.8OR, previous Sever's disease indicates a strong association with Osgood-Schlatter Disease. Although generally suggested, growth velocity and bone maturity are not associated in an age-matched comparison.     

异位骨化的影像学表现（附7例分析）

目的探讨异位骨化的影像学表现。方法回顾性分析本院确诊的7例异位骨化患者影像学资料,总结异位骨化的影像学特征。结果异位骨化累及腕部1例,踝关节2例,膝关节3例,髋关节2例。X线平片上表现为软组织内的条状、片状或层状不规则骨化影,可伴有软组织肿胀;CT可清楚显示骨化区范围;骨化区在MRI T2WI均表现为低信号,周围可见片状高信号。结论异位骨化影像学表现具有一定特异性,掌握其特征性影像学表现并结合临床表现有助于对该病的诊断。     

Ultrasound for diagnosis of apophyseal injuries

Avulsion injuries of the apophysis is a problem in young athletes. A correct diagnosis is necessary for establishing the appropriate treatment and the rehabilitation program. However, it is often difficult to distinguish between a simple muscle strain and an avulsion fracture. The X-ray examination is helpful only when an ossification center of the apophysis exists. Ultrasonography is considered the suitable diagnostic tool for these cases. From June 1988 to June 1993, 243 young athletes were seen with an anamnestic and clinically suspected apophyseal injury of the lower extremity. In all cases X-ray examination and ultrasound examination were performed. In 80 cases the diagnosis was confirmed by X-ray examination and in 97 by ultrasonography. Four criteria were defined for the sonographic examination: (a) a hypoechogenic zone, (b) increased distance to the apophysis, (c) dislocation of the apophysis, and (d) mobility of the apophysis on dynamic examination. These criteria are correlated to (a) edema, (b) lysis, (c) avulsion, and (d) unstable avulsion of the apophysis. Ultrasonography is a proven technique for the detection of apophyseal injuries. In comparison to X-ray examination, it has the advantages of no radiation exposure, early detection even without ossification center, and dynamic examination.     

Drug Testing in Sports

In brief Because of their skeletal immaturity, children and adolescents are subject to a somewhat different set of overuse knee injuries than are adults. Described here are the diagnosis and treatment for the most common growth-related causes of knee pain in active young people: Osgood-Schlatter disease, Sinding-Larsen-Johansson disease, osteochondritis dissecans, bipartite patella, medial plica syndrome, and discoid meniscus. In most cases these conditions respond to conservative treatment.     

低场MR在膝外伤中的应用价值

目的探讨低场(0.35 T)MR在膝外伤中的应用及诊断价值。方法对67例X线、4例同时行CT检查均未见明显异常的膝外伤患者行低场MR常规检查,常规自旋回波(SE)T1WI矢状位、快速自旋回波(TSE)T2WI矢状位及T2脂肪抑制序列矢状位及冠状位成像。结果骨挫伤28例,韧带损伤17例,半月板损伤13例,54例患者关节腔内有不同程度的关节腔积液及周围软组织损伤。结论低场MR可诊断膝关节骨质、关节软骨、半月板、韧带、周围软组织的单一及复合损伤,膝外伤后经X线或CT检查无明显异常,临床体检阳性、症状明显者应首选MRI。     

Get a kick out of this: the spectrum of knee extensor mechanism injuries

At the end of this article, the reader should be able to (1) recognise normal anatomy and anatomical variants of the extensor mechanism of the knee on various imaging modalities, including plain film, ultrasound and MRI; (2) diagnose a broad spectrum of EM injuries in adult and paediatric patients including patellar and quadriceps tendinopathy, Osgood-Schlatter disease, Sindig-Larsen-Johansson syndrome, chondromalacia patellae and patellar fractures on various imaging modalities; and (3) appreciate the important role of imaging in the diagnosis of musculoskeletal injuries.     

髌骨软骨软化症的X线表现(附26例报告)

髌骨软骨软化症,男女皆可罹患,多发生于40岁以后膝部过劳累者。X线征26例均以髌骨后与股骨面软骨糜烂为主要表现。文中并探讨了发病原因、髌上透亮隙”、邻关节假囊肿的形成与X线特征     

Osteogenic sarcoma (report of 18 cases)

Eighteen cases of osteogenic sarcoma of the long bones in the extremities were analyzed in this paper. The pathological basis of the X-ray signs was explained. It was suggested that solitary calcific shadow appearing near the knee joint in young individuals should alert the radiologist to the possibility of osteogenic sarcoma. The X-ray findings of osteogenic sarcoma were characterized by dissociation of osteolysis from ossification. Simultaneous bony destruction both inside and outside the cortex was one of the patterns of erosive bone destruction in osteogenic sarcoma. The distinction between benign and malignant bony spicules, the differences in the relationship between soft tissue mass and subcutaneous fat layer and that between osteomyelitis and the subcutaneous fat layer were discussed.     

Transphyseal linear ossific striations of the distal radius and ulna

Radiologic and histologic analysis of transphyseal linear ossific striations of the distal ulna and radius showed that these striations consist of trabecular bone extending from the metaphysis across all zones of the physis into a small focus of fibrous and necrotic tissue within the epiphyseal cartilage. The focus appears to be a discrete area of epiphyseal ischemia with subsequent necrosis within and around the vasculature of a cartilage canal and probably represents a microscopic response to antecedent trauma that was insufficient to cause macrofailure (fracture) of the physis. The striations did not continue into the epiphyseal ossification center. The consequence is partial osseous bridging across the physis. This bridging is unlikely to cause significant growth damage, since in most cases it does not appear to extend farther into the secondary ossification center.     

原发性滑膜骨软骨瘤病的影像诊断

目的分析原发性滑膜骨软骨瘤病的X线、CT和MRI表现。方法22例原发性滑膜骨软骨瘤病患者均行CT扫描,其中16例拍摄X线平片,2例做MRI检查。结果22例中男13例,女9例。20例为单关节发病,2例为双侧关节同时发病。20例表现为关节内或周围大小不一、数目不等的结节状钙化或骨化影,1例表现为髋关节内分叶状软组织块影伴有钙化,并有髋臼骨质破坏,另1例表现为膝关节内条状软组织密度伴有点状钙化。2例关节骨质破坏,手术证实为软骨结节压迫所致。结论X线平片和CT扫描能够显示钙化或骨化的软骨结节,对未钙化或骨化的软骨结节MRI能够清楚显示。     

去分化软骨肉瘤的影像分析

目的分析去分化软骨肉瘤的X线及CT表现，探讨去分化成分的X线、CT表现特点。方法回顾性分析13例去分化软骨肉瘤的X线及CT表现，并结合临床及组织学特点进行分析研究。结果去分化软骨肉瘤不仅具有典型软骨肉瘤的表现，而且还具有去分化成分的影像特点。13例中8例显示有骨化，11例有骨膜反应，12例有软组织肿快，10例有钙化，其中8例钙化位于病灶中央部位。结论去分化软骨肉瘤具有典型软骨肉瘤所不具备的去分化成分的影像特点，认识这些特殊的影像特点有助于提高对该病的正确诊断。     

骨化性肌炎的多模态影像学表现

目的:探讨骨化性肌炎的X线、CT、MRI、SPECT/CT的特征性表现。方法:回顾性分析56例经病理或随访证实为骨化性肌炎患者的影像学资料,总结其影像学特征,探讨该病的鉴别要点及诊断价值。结果:56例中,位于髋关节23例,肘关节18例,其他部位15例。早期病变12例,CT或MRI表现为软组织水肿、肿胀,无明显骨化成分,可合并邻近骨骼的骨膜反应;中期病变23例,表现为软组织内分层状肿块,病灶中心呈软组织密度或信号,病灶周围呈蛋壳样、絮状骨化影,SPECT/CT表现为病灶整体显像剂异常摄取;晚期病变21例,表现为边界清楚的骨化团块,SPECT/CT显像15例,其中3例未见显像剂摄取,6例病灶中央显像剂摄取,6例病灶周围显像剂不均匀摄取。结论:骨化性肌炎早期缺乏影像学特征,中期蛋壳样骨化是其特征表现,晚期的骨化团块可表现为不同形式的显像剂摄取,多模态影像学的综合应用可提高其临床诊断价值。     

Radiologische Bildgebung der Kniegelenkarthrose

Clinical/methodical issue

Osteoarthritis is the most common degenerative age-related joint disease leading to typical degradation of articular cartilage with severe pain and limitation of joint motion.

Standard radiological methods

Although knee radiographs are widely considered as the gold standard for the assessment of knee osteoarthritis in clinical and scientific settings they increasingly have significant limitations in situations when resolution and assessment of cartilage is required.

Methodical innovations

Analysis of osteoarthritis of the knee with conventional x-ray is associated with many technical limitations and is increasingly being replaced by high-quality assessment using magnetic resonance imaging (MRI) or sonography both in the clinical routine and scientific studies.

Performance

Novel imaging modalities such as MRI or ultrasound enable in vivo visualization of the quality of the cartilaginous structure and bone as well as all articular and periarticular tissue. Therefore, the limitations of radiographs in assessment of knee osteoarthritis could be overcome by these techniques. This review article aims to provide insights into the most important radiological features of knee osteoarthritis and systematic visualization with different imaging approaches.

Practical recommendations

The demographic development in western industrialized countries predicts an increase of ageing-related osteoarthritis of the knee for the next decades. A systematic radiological evaluation of patients with knee osteoarthritis includes the assessment of the periarticular soft tissue, cartilaginous thickness, cartilage volume, possible cartilage defects, the macromodular network of hyaline cartilage, bone marrow edema, menisci and articular ligaments. Modern imaging modalities, such as MRI and sonography allow the limitations of conventional radiography to be overcome and to visualize the knee structures in great detail to quantitatively assess the severity of knee osteoarthritis.     

Calcaneal apophysitis (Sever's disease) — a common cause of heel pain in young athletes

The most common syndromes in young athletes are apophysitis, especially Osgood-Schlatter and Sever's disease. According to a retrospective questionnaire of 67 patients with Sever's disease treated at the Sports Medical Research Unit in Turku, the main sports causing this syndrome were related to running. The pain appeared on average at the age of 12.2 years (boys 12.5 and girls 11.8) and was unilateral in 85% of the cases; 54% of the patients were boys. The pain was typically worst at the end of exercise and afterwards. On average, the patients were forced to stop training because of pain for 1.3 months (< 2 weeks in 55% of the patients) and the syndrome interfered with fully effective training for 2 months in 28% of the cases. After a 2-month symptom-free period, Sever's disease recurred in 28% of the cases. Later, 48% of the patients contracted also Osgood-Schlatter disease. The diagnosis of Sever's disease is clinical and the treatment is symptomatic. Sever's disease is cured by the fusion of the epiphysis with the calcaneal bone.     

原发性骨网状细胞肉瘤的临床及X线分析

目的探讨原发性骨网状细胞肉瘤的临床及X线表现,以期提高对本病的诊断和鉴别诊断水平。方法结合临床表现、手术及病理所见回顾性分析经病理证实的11例原发性骨网状细胞肉瘤的X线特点。结果长管状骨5例(45%),椎骨、肋骨及骨盆各2例(各占18%)。主要X线改变为溶骨性破坏,有软组织肿块者7例,病理骨折1例,骨膜反应仅见2例且较轻微。结论当X线发现溶骨性恶性病变伴软组织肿块,且临床症状较其他骨恶性肿瘤为轻者,应考虑原发性骨网状细胞肉瘤的可能,最后确诊有赖于病理学证实。     

Magnetic resonance imaging of the clavicular ossification

Assessment of the degree of ossification of the medial clavicular epiphyseal cartilage is of vital importance in forensic age diagnostics of living individuals aged more than 18 years. To date, reference studies on the assessment of clavicular ossification using imaging procedures only relate to conventional radiography and computed tomography (CT). In this study, magnetic resonance (MR) scans of 54 sternoclavicular joints of bodies aged between 6 and 40 years were evaluated prospectively. All of the examined medial clavicular epiphyseal cartilages permitted an assessment of the degree of ossification. Stage 2 was first observed at the age of 15.0 years, the earliest age at which stage 3 was observed was 16.9 years, and stage 4 was first observed at the age of 23.8 years. The observed age intervals of the respective degrees of ossification correspond to the known data from X-ray and CT scan examinations. The achieved results should be examined with a larger number of cases. A modified examination protocol is required for the MR examination of the medial clavicular epiphyseal cartilage for the purpose of forensic age diagnostics of living individuals.