Osteochondral fractures of the dome of the talus.

Osteochondral fracture of the talar dome is an uncommon lesion occurring after ankle inversion and tearing of the lateral ligaments. This lesion can be overlooked if internal oblique radiographs are not obtained. The value of tomography is discussed. Symptoms may persist for many months if accurate radiographic diagnosis is delayed. Prompt arthrotomy is indicated to prevent post-traumatic arthritis of the ankle joint.     

Snowboarder's talus fractures experimentally produced by eversion and dorsiflexion

BACKGROUND: Fracture of the lateral process of the talus is an unusual injury that has received heightened attention in recent years because of its association with snowboarding. The diagnosis is often confused with that of lateral ankle sprain. If left untreated, it can cause long-term impairment, including osteoarthritis and subtalar joint degeneration. It is generally thought to result from dorsiflexion and inversion. However, few experimental studies have been conducted to investigate the injury mechanism. HYPOTHESIS: Eversion of a dorsiflexed ankle is more likely to fracture the lateral process of the talus than inversion of a dorsiflexed ankle. STUDY DESIGN: Controlled laboratory study. METHODS: Ten cadaveric leg specimens were subjected to dynamic inversion or eversion of an axially loaded and dorsiflexed ankle. RESULTS: Inversion failed to produce any fractures in three injured specimens. However, all six specimens subjected to eversion sustained a fracture of the lateral process of the talus. CONCLUSIONS: The incidence of fracture of the lateral process of the talus was significantly higher in the eversion group compared with the inversion group. Clinical Relevance: Eversion of an axially loaded and dorsiflexed ankle may be an important injury mechanism for fracture of the lateral process of the talus among snowboarders.     

Imaging of fractures of the lateral process of the talus,a frequently missed diagnosis

Although if fractures of the lateral process of the talus (LPT) have been considered rare the widespread diffusion in snowboard practice has resulted in a dramatic increase in their frequency. If unrecognized they can result in secondary osteoarthritis of the ankle and/or talo-calcaneal joints and chronic pain and stiffness. Due to the complex anatomy of the region, these fractures are difficult to detect by standard radiographs. A high degree of suspicion is then necessary to diagnose them. Once suspected on the basis of physical examination and/or non concluding radiographs, computed tomography (CT) is the best modality to confirm the diagnosis and accurately appreciate the number of the fragments and their position which have therapeutic consequences (medical vs. surgical treatment). A better knowledge of these lesions seems necessary to the general radiologist to allow an early diagnosis in order to avoid chronic sequel. The purpose of this article is to report three additional cases of LPT fractures and discuss their pathogenesis, diagnosis and treatment.     

Partial Hawkins sign in fractures of the talus: a report of three cases

OBJECTIVE: We introduce the concept of the partial Hawkins sign in three cases of talar neck fracture that are associated with incomplete avascular necrosis. Our objective is to call attention to the intraosseous blood supply of the talar body, which can be interrupted by fractures to produce patterns of incomplete avascular necrosis. CONCLUSION: We conclude that the Hawkins sign does not always have to be complete. Fractures of the talus occasionally can lead to partial avascular necrosis because of the disruption of end arteries within the body of the talus, even without subluxation or dislocation. Early recognition of the partial Hawkins sign should lead to MRI evaluation that can more readily define the involvement of the talar body and assist the treating physician in recommending when the patient can bear weight.     

Physeal fractures aboutthe ankle and osteochondral lesions of the talus in the skeletally immature athlete

In children and adolescents, many sports related ankle injuries result in physeal fractures. Excessive forces applied tothe skeletally immature ankle commonly result in Salter Harris 11, 111, and IV fractures. To minimize the potential for growth disturbance of the distal tibia and articular incongruity of the ankle joint, reduction with fixation is recornmended for fractures displaced greater than 2 mm. Transitional fractures of the ankle, ie, the juvenile Tillaux and triplane fractures, occur in the older adolescent athlete. Restoration of the articular surface is of primary importance in treating these injuries. Osteochondral lesions of the talus are often the cause of persistent ankle pain after a seemingly minor ankle injury. Immobilization and progressive rehabilitation are successful in treating the majority of these injuries in the immature athlete. Arthroscopic treatment techniques are recommended for treatment of osteochondral lesions not responsive to conservative measures.     

Low-risk stress fractures

Stress fractures can occur in almost any bone in the body, with the lower extremity weightbearing bones, especially the tibia, tarsals, and metatarsals, being affected most frequently. Although the cause of these fractures is multifactoral, repetitive physical forces without adequate rest are the primary culprits. Stress fractures may be broadly classified as low-risk or high-risk injuries. Low-risk stress fractures, the topic of this review article, can be diagnosed through a thorough history, physical examination, and radiographs. Nuclear scintigraphy is occasionally necessary for confirmation, especially for fractures of the spine and pelvis. When diagnosed early and treated with restriction of activity, low-risk stress fractures have a favorable prognosis.     

空心加压螺钉联合可吸收材料治疗距骨骨折的临床疗效分析

距骨骨折是足踝部严重创伤,近年来有明显上升趋势。距骨无单独血液供应,创伤及手术损伤均可影响其血液供应,增加发生距骨缺血性坏死及创伤性关节炎并发症的发生率[1-2]。在显微无创手术技术的保障下,越来越多的距骨骨折选择手术治疗。多数学者选用空心加压螺钉固定距骨骨折[3],亦有选用可吸收材料固定距骨骨折者[4]。本研究选用空心加压螺钉联合可吸收材料固定治疗,比较两种治疗方法的疗效。     

Navicular stress fractures

Since the stress fracture of the tarsal navicular was first described in 1970, awareness of the injury has increased, and navicular stress fractures have represented up to 35% of stress fractures in recent series. However, these injuries remain difficult to diagnose and treat because of their often vague clinical presentation and the poor correlation between radiographic and clinical findings.     

Rib stress fractures

The ribs are an uncommon site of stress fracture. Typical locations are the first rib anterolaterally, the fourth through ninth ribs laterally and posterolaterally, and the posteromedial upper ribs. Muscular forces are predominantly responsible for these fractures. This article reviews the mechanisms of injury in various activities and illustrates the scintigraphic appearance of rib stress fractures.     

Sacral stress fractures

Sacral stress fractures are a relatively common occurrence and can be a debilitating source of low back pain. They generally occur in two distinctly different patient populations, and are of two different etiologies. Sacral insufficiency-type fractures are seen in elderly osteoporotic persons, and fatigue fractures are seen young active individuals. Although the clinical presentation of these fractures is similar, medical rehabilitation and interventional spine management strategies differ according to etiology. Although conservative management strategies have resulted in good outcomes, other treatment options have recently developed. This article provides an overview of the clinical presentation, pathology, and treatment options for sacral stress fractures and discusses some of the recent literature surrounding this interesting topic.     

Epidemiology of stress fractures

Stress fractures are a frequent cause of injury in competitive and recreational athletes. Although a number of epidemiologic studies have been conducted, the populations studied and data collection methods have varied. This article presents an overview of injury epidemiology and reviews the current body of literature regarding the occurrence of stress fractures in athletes. Given the heterogeneity of the populations studied and the variations in data collection, few broad conclusions can be drawn. There is a pressing need for large prospective studies to better establish the risks of stress fracture by sport, age, and gender.     

Imaging of stress fractures

The imaging evaluation of a patient who has a clinically suspected stress reaction or fracture should begin with high-resolution radiographs of the area in question. In inconclusive or indeterminate cases, additional imaging should be obtained. CT provides exquisitely fine osseous detail, in multiple planes, often demonstrating the endosteal remodeling or fracture line that is not apparent on conventional radiographs. The sensitivity of nuclear scintigraphy depicts areas of even subtle osseous turnover and stress remodeling. Ultrasonography, used increasingly in the evaluation of the musculoskeletal system, can provide a limited evaluation of the superficial osseous structures, providing an imaging alternative, especially in patients who are MRI-incompatible. MRI, however, provides the most comprehensive evaluation of stress injuries, revealing both functional and morphologic information about the bone.     

Imaging of stress fractures of the spine

Back pain caused by stress fractures, fatigue, or insufficiency, affects varied patient populations based on the level of physical activity and bone mineral density. Stress fractures may involve the vertebral body, pars interarticularis, and the pedicle; often overlooked are stress fractures of the sacrum or bony pelvis, which can mimic pain of spinal origin and delay diagnosis. The choice of optimal imaging (radiographs, nuclear medicine, magnetic resonance imaging, and computed tomography) also depends on the patient population under study and the clinically suspected diagnosis. The diagnosis typically determines which imaging modality is best to follow healing or progression.     

Nonunions of stress fractures of the tibia

Stress fractures of the tibia commonly occur in the proximal metaphysis and heal readily with rest. Fractures of the middle third of the tibia, on the other hand, are uncommon. We encountered six stress fractures of the middle third of the tibia over a 5 year period. None of these fractures healed with simple immobilization. One was treated with electromagnetic stimulation and failed to unite 2 years after presentation. One patient underwent a biopsy of the lesion without bone grafting and it had not healed when he was last seen. One patient sustained two acute complete fractures, and the stress fracture finally healed after the second acute fracture was openly reduced and internally fixed. The other three lesions were excised and grafted because of failure to unite. They all healed promptly. Stress fractures of the middle third of the tibia are unusual lesions. However, care must be taken in treating them. The patient must protect the extremity until the fracture has completely healed. Surgical excision and bone grafting of the lesion may be required if the fracture does not heal with plaster immobilization.     

Treatment of stress fractures: the fundamentals

This article is an introduction to the fundamentals of stress fracture management. Extrinsic and intrinsic factors, that may play a role in the development of stress fractures, are discussed and incorporated as possible treatment options. Different treatment modalities including ultrasound and electromagnetic fields are addressed, with an emphasis on literature support.     

Spontaneous stress fractures of the femoral neck

The diagnosis of spontaneous stress fractures of the femoral neck, a form of insufficiency stress fracture, can be missed easily. Patients present with unremitting hip pain without a history of significant trauma or unusual increase in daily activity. The initial radiographic features include osteoporosis, minor alterations of trabecular alignment, minimal extracortical or endosteal reaction, and lucent fracture lines. Initial scintigraphic examinations performed in three of four patients showed focal increased radionuclide uptake in two and no focal abnormality in one. Emphasis is placed on the paucity of early findings. Evaluation of patients with persistent hip pain requires a high degree of clinical suspicion and close follow-up; the sequelae of undetected spontaneous fractures are subcapital fracture with displacement, angular deformity, and avascular necrosis of the femoral head.     

Imaging of stress fractures in the athlete

Osseous stress fractures and stress reactions represent the effect of abnormal repetitive stress on normal bone. An accurate and thorough clinical history and sequential radiographs often suffice 40 make the diagnosis especially when the fracture occurs in one of the common locations, such as the tibia, metatarsals, or calcaneus. In cases that are atypical in location or clinical presentation the authors rely more on MR imaging, radionuclide bone scanning, and occasionally CT. MR imaging detects early changes of osseous stress injury and allows precise definition of anatomy and extent of injury, and is the preferred modality for evaluating the continuum of osseous manifestations of stress injury. MR imaging is useful in evaluating shin splints, early osseous stress injuries, and overt stress fracture. In the elite athlete prompt diagnosis and early rehabilitation are the goals.     

Femoral neck stress fractures

Femoral neck stress fractures are unusual but not rare athletic injuries. In one large series they accounted for 5% of all stress fractures. Early recognition of the signs and symptoms of this injury is important, as objective findings are often delayed. The potential problems from this fracture are serious. The aetiology includes repeated force above a certain load without internal bone response time. Loss of shock absorption due to muscle fatigue and limitation of ankle motion by boots or splints may also play a role. The diagnosis is based on the finding of groin pain and radiographic testing, which often requires plain films and bone scintigraphy. Regular radiographic findings present in stages progressing from a normal film through sclerosis to a disruption of the cortex and displacement. Bone scintigraphy may be positive 2 or more weeks before plain film changes are present. Classification schemes follow the radiographic changes. A classification system and treatment plan may be based on 3 categories of these fractures--compression side, tension side and displaced femoral neck fracture. Treatment ranges from rest with early symptoms to surgical stabilisation for any widening of cortical cracks and/or displaced fractures. Prompt diagnosis and carefully supervised treatment is the key to preventing displacement. Prolonged disability secondary to pain, nonunion or avascular necrosis is associated with displacement of the femoral neck stress fracture.     

Femoral neck stress fractures

Fifty-four femoral neck stress fractures were studied prospectively to evaluate treatment methods. Fifty-four fractures in 49 patients were identified in a 4 year prospective study that included 1,049 stress fractures of all types. From our evaluation of treatment methods, a modification of existing classification systems was developed based on radiographic findings and treatment. Differences from earlier studies were noted in racial diversity, in nonprogression of tension-side fractures, and in return to function.