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A case of chronic, progressive avulsion of the anterior superior iliac spine leading to the formation of a long, attenuated spur of bone in an 18-year-old black male break dancer is described. The mechanism of formation appeared to be repetitive avulsion from break dancing.
Tibiae from 60 male Wistar rats, aged 13 +/- 1 weeks, were divided into six groups for mechanical and histological testing. Bones were loaded repetitively in torsion at 90 deg.s-1. Group 1 was subjected to 5,000 loading cycles at a twist angle of 3.6 degrees, groups 2-5 to 10,000 cycles at 3.6, 5.4, 7.2, and 9.0 degrees, respectively, and group 6 was tested to failure. Six transverse sections from the middiaphysis were then cut, bulk-stained in basic fuchsin, and hand ground to 30-50 microns to examine the presence of microcracks. Cracks were classified as running parallel to lamellae, crossing lamellae, crossing the full thickness of the cortex, or invading vascular canals. Results for fatigue testing showed that the tibiae exhibited a gradual decrease in torque (P less than 0.05), average stress (P less than 0.01), stiffness (P less than 0.01) and energy absorbed (P less than 0.01) from the initial loading cycle. Analysis of microdamage showed an increase in the variety of cracks from groups 1-5. Analysis of deviance demonstrated a strong dependence of crack probability on the level of loading for all crack types (P less than 0.05) except those crossing lamellae. This study reinforces the evidence that yielding of bone observed during repetitive loading is caused by diffuse structural damage such as microcracking or debonding.
A large aneurysmal bone cyst of the upper tibia in a 17-year-old patient was treated by superselective embolization with excellent clinical and radiological results. Extensive curettage and detailed pathologic analysis performed 2 years following embolization revealed only healing bone. The presented case and reviewed cases in the literature indicate that embolization is a promising method for definitive therapy of the aneurysmal bone cyst.
The material properties of normal cadaveric human cartilage in the ankle mortice (tibiotalar articulation) were evaluated to determine a possible etiologic mechanism of cartilage injury of the ankle when an obvious traumatic episode is not present. Using an automated indentation apparatus and the biphasic creep indentation methodology, creep indentation experiments were performed in five sites in the distal tibia, one site in the distal fibula, and eight sites in the proximal talus of 14 human ankles (seven pairs). Results showed significant differences in the mechanical properties of specific human ankle cartilage regions. Topographically, tibial cartilage is stiffer (1.19 MPa) than talar cartilage (1.06 MPa). Cartilage in the anterior medial portion of the tibia has the largest aggregate modulus (HA = 1.34 MPa), whereas the softest tissue was found to be in the posterior lateral (0.92 MPa) and the posterior medial (0.92 MPa) regions of the talus. The posterior lateral ridge of the talus was the thickest (1.45 mm) and the distal fibula was the thinnest (0.95 mm) articular cartilage. The largest Poisson's ratio was found in the distal fibula (0.08). The lowest and highest permeability were found in the anterior lateral regions of the astragalus (0.80 x 10(-15) m4N-1sec-1) and the posterior medial region of the tibia (1.79 x 10(-15) m4N-1sec-1), respectively. The anterior and posterior regions of the lateral and medial sites of the tibia were found to be 18-37% stiffer than the anatomically corresponding sites in the talus. The biomechanical results may explain clinically observed talar dome osteochondral lesions when no obvious traumatic event is present. Cartilage lesions in a repetitive overuse process in the ankle joint may be related to a disparity of mechanical properties between the articulating surfaces of the tibial and talar regions.
In an ongoing prospective study of 14 recreational athletes (12 males and 2 females, mean age 44.2 +/- 7.1 years) with unilateral chronic Achilles tendinosis, we investigated the effect of treatment with heavy-loaded eccentric calf-muscle training. Pain during activity (recorded on a VAS scale) and isokinetic concentric and eccentric calf-muscle strength (peak torque at 90 degrees /second and 225 degrees /second) on the injured and noninjured side were evaluated. In this group of patients, we examined areal bone mineral density (BMD) of the calcaneus after 9 months (range 6-14 months) of training. BMD of the injured side (subjected to heavy-loaded eccentric training) was compared with BMD of the noninjured side. Before onset of heavy-loaded eccentric training, all patients had Achilles tendon pain which prohibited running activity, and significantly lower concentric and eccentric plantar flexion peak torque on the injured compared with the noninjured side. The training program consisted of 12 weeks of daily, heavy-loaded, eccentric calf-muscle training; thereafter the training was continued for 2-3 days/week. The clinical results were excellent-all 14 patients were back at their preinjury level with full running activity at the 3 month follow-up. The concentric and eccentric plantar flexion peak torque had increased significantly and did not significantly differ from the noninjured side at the 3 and 9 month follow-up. There were no significant side-to-side differences in BMD of the calcaneus. There was no significant relationship between BMD of the calcaneus and calf-muscle strength. As a comparison group, we used 10 recreational athletes (5 males and 5 females) mean age 40.9 years (range 26-55 years), who were selected for surgical treatment of chronic Achilles tendinosis localized at the 2-6 cm level. Their duration of symptoms and severity of disease were the same as in the experimental group. There were no significant side-to-side differences in BMD of the calcaneus preoperatively, but 12 months postoperatively BMD of the calcaneus was 16.4% lower at the injured side compared with the noninjured side. Heavy-loaded eccentric calf-muscle training resulted in a fast recovery in all patients, equaled the side-to-side differences in muscle strength, and was not associated with side-to-side differences in BMD of the calcaneus. In this group of middle-aged recreational athletes, BMD of the calcaneus was not related to calf-muscle strength.
BACKGROUND: The Society of American Gastrointestinal Endoscopic Surgeons (SAGES) Task Force on Ergonomics conducted a subjective and objective assessment of ergonomic problems associated with laparoscopic instrument use. The goal was to assess the prevalence, causes, and consequences of operational difficulties associated with the use of laparoscopic instruments. METHODS: A questionnaire was distributed asking respondents to rate the frequency with which they experienced pain, stiffness, or numbness in several body areas after laparoscopic operations. An ergonomics station was assembled to quantify forearm and thumb muscle workload. Processed electromyogram (EMG) signals were acquired from 27 volunteer surgeon subjects while they completed simulated surgical tasks using a hemostat and an Ethicon laparoscopic grasper, with the aid of an endoscopic trainer and video monitoring system. RESULTS: Of 149 surgeons responding to the questionnaire, 8% to 12% reported frequent pain in the neck and upper extremities associated with laparoscopic surgery. The ergonomics station demonstrated that the peak and total muscle effort of forearm and thumb muscles were significantly greater (p < 0.01) when the grasping task was performed using the laparoscopic instrument rather than the hemostat. CONCLUSION: These findings indicate that laparoscopic surgical technique is more taxing on the surgeon.
The benefit of regularly performed physical activity as a fundamental component of a healthy lifestyle is uncontradicted. The number of persons who participate in sports in Germany is approximately more than 40 million people, whereof 27.5 million are organised in sport associations. Every year 1.5-2 million sports injuries occur in Germany, which represent 25-30% of all accidents. The costs for treatment amount to a total of 1.5 billion euros. It is estimated that 80% of all sports injuries could be prevented if training and competition were performed correctly. The patterns and risk of injuries differ between particular sport disciplines and are therefore difficult to estimate. Knowledge of specific injury risks is indispensable for prevention of sports injuries. Furthermore this knowledge facilitates both sports physicians' diagnosis and therapy and guidance of the patient. In this review epidemiological data of sport traumatology are surveyed, patterns of injuries of particular sports are described in detail and prevention strategies are given. In a separate section specifics of sports injuries in children are discussed.
Hypothenar hammer syndrome (HHS) is ischemia of the distal ulnar artery caused by injury to the ulnar part of the palmar arch. This disease often involves workers who frequently use the hypothenar part of the hand as a hammer. The aneurysmatic form of HHS represents an indication for operative treatment; the thrombotic form is treated mainly conservatively. In our opinion, the symptomatic thrombotic form represents an indication for operation if symptoms persist during conservative therapy, particularly if symptoms progress. In fresh embolic occlusions, regional thrombolysis is usually successful. We present here the symptomatic treatment and course in two patients with complaints increasing during conservative therapy. The patients reported progressive Raynaud's phenomenon of the fingers. Angiography confirmed corkscrew-like aneurysmatic configuration of the distal ulnar artery and subsequent embolization of digital arteries. In both cases, we removed the source of the embolism with resection of the involved arterial segment and anastomosis with autologous vein grafts.
A 25-year-old carpenter with severe localised Raynaud syndrome of the lateral three fingers of his right hand is described. The patient reported digital ischaemia caused by cold or vibration, and especially when both were present simultaneously. He was initially diagnosed with thrombangitis obliterans, but failed to respond to intravenous prostaglandin therapy, pentoxifyllin or aspirin. Diagnostic procedures performed in our hospital, especially angiography, confirmed our suspicion of hypothenar hammer syndrome. Radiological examination revealed severe anatomical and functional changes of the distal ulnar artery and, digital arteries of the affected digits. The differential diagnosis of Raynaud syndrome should include the hypothenar hammer syndrome as a possible cause. Early diagnosis and prevention of hand trauma is the only possible way to stop progression of this disease, which leads to invalidity.
The hypothenar hammer syndrome (HHS) is a rare form of secondary Raynaud's phenomenon in workers who frequently use the ulnar side of the palm as a hammer. Clinically the patient with HHS shows neurologic symptoms such as paresthesia, numbness and pain and signs of vascular insufficiency such as coldness, pallor, discoloration and blanching of the affected ulnar sided fingers. The diagnosis is verified by angiography, showing thrombosis or aneurysm of the distal ulnar artery. We report on the treatment and outcome of 5 patients with HHS. All patients were painfree after treatment. But with the ongoing working habit of using the hand as a hammer there is always the risk of a recurrence. Therefore the job environment has to be changed considerably and the most effort should go into prevention and prophylaxis. If the change of the working habit is not possible, the job is clearly at stake.
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The exact cause of the idiopathic osteoarthritis of the hip has not been identified, although the cause of hip degeneration in developmental dysplasia can clearly be attributed to an excessive axial loading. Based on the development of a surgical technique for the safe surgical dislocation of the hip and the associated possibility of intraoperative joint evaluation, we have found motion-induced joint damage in many of these hips. This begins peripherally at the acetabular rim, progressing centrally. This so-called "femoroacetabular impingement" (FAI), leads, by an increased acetabular coverage and/or a missing sphericity of the femoral head, to an abutment of the femoral head/neck junction against the acetabular rim, or even entering of the non-spherical femoral head into the hip. It initiates damage to the labrum and/or acetabular cartilage. Frequently, this becomes symptomatic in the second or third decade of life in patients with increased sport activity. Based on the predominance of the acetabular or femoral pathology, two different types of FAI, the pincer and the cam can be differentiated. Apart from these morphological alterations, supraphysiological mobility and overuse can contribute to FAI. The impingement concept has led to a new type of mainly intracapsular hip surgery.
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Overuse tendon injury is one of the most common injuries in sports. The etiology as well as the pathophysiological mechanisms leading to tendinopathy are of crucial medical importance. At the moment intrinsic and extrinsic factors are assumed as mechanisms of overuse tendon injury. Except for the acute, extrinsic trauma, the chronic overuse tendon injury is a multifactorial process. There are many other factors, such as local hypoxia, less of nutrition, impaired metabolism and local inflammatory that may also contribute to the development of tissue damage. The exact interaction of these factors cannot be explained entirely at the moment. Further studies will be necessary in order to get more information.
Sport climbing shows an enormous increase in participation, evolving to more popularity, including even school sport activity on high standards. Therefore the number of climbing related injuries is increasing and becomes a more frequently encountered medical problem. Typical climbing associated injuries involve predominantly the upper limb. Overuse injuries are the most common climbing related injuries. The clinical examination is the first line investigation, which is often limited especially in the acute phase. However, an exact diagnosis is desirable for therapeutic management. Imaging modalities have shown to be capable for detection of climbing related injuries. An overview about the current use of x-ray, ultrasound and magnetic resonance imaging in different climbing related overuse injuries is presented.
Soccer is one of the most popular sports worldwide. There is a high incidence of injuries in soccer in which several intrinsic and extrinsic factors play a part. Most injuries are minor, self-limiting and do not need extensive medical treatment or imaging. Imaging can be required for several reasons e.g. when the clinical findings are doubtful, to replace arthroscopy (i. e. of the knee) or for prognostic reasons. All imaging modalities available to the radiologist can be used but MRI is the most valuable imaging modality with its superior contrast resolution and multiplanar capabilities. Basically, injuries in the soccer player can occur anywhere in the body like in every sport. The lower extremities, more specific the knee and ankle, are however the most injured parts.
The increasing demands on the adolescent athlete in high performance sports puts high biomechanical stress on the growing structures of the active and passive locomotor system. The "growing factor" itself increases stretching forces on tendon insertions, which are often overloaded when a physical demanding sport is performed additionally. The apophysis is an ossification nucleus near the tendon insertion, which appears before the growing age resumes and these apophysis finally fuses with the adjacent bone. The tensile forces from vigorous sports activity leads to a chronic or acute avulsion of the ossifying tendon insertion. The radiological appearance of this apophyseal damage with ossification and osteolytic processes is sometimes difficult with respect to differential diagnoses. Apophyseal impairment is associated with pain, tenderness to palpation and decreased muscle function. If it is not diagnosed and treated properly it can lead to end of career in many adolescent athletes.
The hypothenar hammer syndrome (HHS) is characterized by lesions of the ulnar artery secondary to repetitive trauma to the hypothenar eminence. We report the case of an orthopedic surgeon with HHS due to his occupational practice. Angiography and MRI confirmed an aneurysm of the ulnar artery and embolic occlusions of his carpal and digital arteries. Patency was reestablished with regional thrombolysis using rt-PA. So far there have been no reports on thrombolysis with rt-PA in HHS.