Roger Kerr

Benign and malignant cartilage tumors of bone and joint: their anatomic and theoretical basis with an emphasis on radiology, pathology and clinical biology

Abstract We reviewed 845 cases of benign and 356 cases of malignant cartilaginous tumors from a total of 3067 primary bone tumors in our database. Benign cartilaginous lesions are unique because the epiphyseal plate has been implicated in the etiology of osteochondroma, enchondroma (single or multiple), periosteal chondromas and chondroblastoma. In the first part of this paper, we will review important clinical, radiologic and histologic features of intramedullary cartilaginous lesions in an attempt to support theories related to anatomic considerations and pathogenesis.

A Comparison of MRI and Clinical Examination of Acute Lateral Ankle Sprains

Because of its excellent soft tissue contrast and ability to demonstrate soft tissue structures, magnetic resonance imaging is ideally suited to the evaluation of the soft tissues surrounding the ankle, including the lateral collateral ligaments. This study was undertaken to compare the clinical evaluation of 15 patients who suffered inversion injuries of the ankle with the results found on magnetic resonance imaging within 48 hours of the injury. Physical examination was found to be 100% accurate in the diagnosis of grade III ligament injuries but only 25% accurate in the diagnosis of grade II injuries. Clinicians most often underestimate the damage with a grade II ligament tear. Furthermore, other associated injuries, such as significant capsule ruptures and tendon damage, were often overlooked at physical examination.

MR imaging in tarsal tunnel syndrome

Magnetic resonance imaging was used to demonstrate the normal anatomy of the tarsal tunnel in two volunteers and to evaluate 33 feet in 27 patients with tarsal tunnel syndrome. The tarsal tunnel is a fibroosseous channel extending from the ankle to the midfoot, through which the medial tendons and the posterior tibial neurovascular bundle pass. Tarsal tunnel syndrome is a compression neuropathy of the posterior tibial nerve or one of its branches and may be caused by a variety of pathologic lesions. Magnetic resonance imaging demonstrated a mass lesion in five feet, dilated veins or varicosities in eight feet, fracture or soft tissue injury in five feet, fibrous scar in two feet, flexor hallucis longus tenosynovitis in six feet, and abductor hallucis muscle hypertrophy in one foot. Six feet were normal on MR imaging. The findings of MR imaging were confirmed in 17 of 19 patients that went to surgery. Magnetic resonance is useful for localizing lesions within the tarsal tunnel and for determining the lesion extent and relationship to the posterior tibial nerve and its branches.

Plantar compartmental infection in the diabetic foot. The role of computed tomography.

This review discusses the role of computed tomography (CT) in the evaluation of extent of plantar soft tissue infection in the diabetic foot. CT abnormalities are correlated with conventional radiography, results of preoperative aspiration cultures, intraoperative assessment, and bone, gallium, and 111In-leukocyte scan findings. Plantar soft tissue disease respects compartmental boundaries in general, with transcompartmental spread possible along musculotendinous units that normally transgress the intervening fascial septae. CT correlates well with the extent of infection as determined by other modalities, but cannot precisely predict its proximal boundary due to gradual transition between unequivocally abnormal and normal tissue. CT may be useful in establishing an appropriate level for contemplated amputation and can detect extension of superficial diabetic foot infections at an earlier stage than existing clinical methods, potentially resulting in less extensive surgical procedures.

Digital arthrography in the evaluation of painful joint prostheses.

Digital arthrography was accomplished in 16 patients who had painful prostheses. In each instance, resulting arthrographic abnormalities were compared with those apparent on subsequent overhead radiographs. Results indicate the potential value of the digital technique in this clinical setting. The examination is easy to perform and rapid, and allows the examiner to view the changing images in the subtraction mode. Image manipulation and enhancement are also possible.

CT analysis of proximal femoral trabecular pattern simulating skeletal pathology.

The proximal femoral trabecular pattern was studied in 20 patients, six cadavers, and 20 macerated specimens using plain film radiography and CT. A distinctive pattern of increased radiodensity in the proximal femur is described in patients and specimens with osteoporosis and osteoarthritis. The appearance is similar to that of an enchondroma or bone infarct. This pattern may be explained by biomechanical principles and is created by unmasking or hypertrophy of preexistent, reinforcing trabeculae. Confusion with osseous pathology can be avoided if the radiologist is aware of this pattern.

Sliding-screw plate fixation of proximal femoral fractures: Radiographic assessment

The sliding compression screw-sideplate combination is currently the most widely empoloyed device for internal fixation of stable and unstable intertrochanteric fractures of the femur. The normal and abnormal radiographic appearances of this device in the immediate post-operative period are discussed. Potential long-term complications including mal- or non-union, intra-articular penetration, metal failure, rotation of the proximal fracture fragment, disengagement, trochanteric bursitis, leg length discrepancy, delayed cervical stress fracture, and ischemic necrosis are reviewed.