Biomedical subjects

A J Cook

Publications and source records attributed to A J Cook.

42 records · Page 3Linked to original sources

PubMedDate not supplied

Madelung deformity in skeletally immature patients: morphologic assessment using radiography, CT, and MRI.

PURPOSE: The purpose of this study was to define the pathoanatomy of the distal radius and surrounding soft tissues, identify the factors that may contribute to diminished forearm rotation, and relate these findings to alterations in wrist motion in skeletally immature patients with the Madelung deformity. METHOD: Four skeletally immature female patients with bilateral Madelung deformities (eight wrists) underwent evaluation of each wrist with radiography, CT, and MRI to assess the morphology of the deformity. Two patients (four wrists) had isolated idiopathic Madelung deformities, and two patients (four wrists) had Madelung deformities secondary to dyschondrosteosis. RESULTS: Radiographically, all wrists demonstrated dorsal bowing of the radius, marked ulnar tilting of the radius and radial tilting of the ulna, volar tilting of the distal articular surface of the radius, and triangulation of the epiphysis. On CT, patients with the idiopathic deformity demonstrated dorsal ulnar subluxation and relative supination of the carpus with respect to the distal radius. Patients with dyschondrosteosis demonstrated no ulnar subluxation and relative pronation of the carpus. All wrists demonstrated a fixed pronated deformity of the distal radius. On MRI, a physeal bar that bridged the distal metaphysis of the radius to the epiphysis was identified in all eight wrists, located on the volar aspect of the radius at the lunate facet. An anomalous volar ligament, a volar radiotriquetral ligament, and the short radiolunate ligament were hypertrophied in seven wrists. CONCLUSION: Based on its location, it is likely that a physeal bar impedes the normal development of the distal radius ulnarly. Hypertrophy of the short radiolunate ligament may be an important contributing factor to carpal pyramidalization owing to tethering on the volar pole of the lunate. Diminished forearm rotation is likely related to carpal malalignment, a fixed pronated deformity of the distal radius, and dorsal bowing of the radius.

Adolescent↗

PubMedDate not supplied

Suspected scaphoid fractures in skeletally immature patients: application of MRI.

PURPOSE: The purpose of our study was to evaluate the MR findings in the wrists of pediatric patients who have sustained acute wrist injuries and to determine if this imaging method yields more information than combined serial radiographs and physical examinations. METHOD: Eighteen skeletally immature patients (11 boys and 7 girls, age range 8-15 years) who had presented to the emergency room within 2 days following acute wrist trauma underwent serial clinical, radiographic, and MR examinations if there was a suspicion of a scaphoid fracture. RESULTS: Ten patients had a scaphoid abnormality on MR images. Six had fractures and four had regional bone marrow edema. Initially, all but two fractures were radiographically occult, although the other fractures eventually became evident on later studies. Those with marrow edema did not progress to fractures. Obliteration of the scaphoid fat stripe occurred in five patients with a scaphoid fracture and in six patients who did not have a fracture. Dorsal soft tissue swelling occurred in eight patients, five of whom had scaphoid fractures. Seven patients had evidence of extensor tenosynovitis on MRI. CONCLUSION: A normal initial MR image had a negative predictive value of 100%. Persistent snuffbox pain may represent injury to the scaphoid, extensor tendons, or dorsal soft tissues. An outcome study evaluating the benefits of early application of MR in the pediatric population is warranted.

Acute Disease↗

PubMedDate not supplied

Treatment of osteoid osteoma by computed tomography guided excision in the pediatric patient.

An osteoid osteoma is a benign lesion that can occur in any bone. Controversy exists regarding treatment of this condition. This study demonstrates that the nidus of an osteoid osteoma can be disrupted and removed by use of the CORB biopsy system guided by computed tomography (CT) scan. Of nine patients followed for an average of 42.5 months (range 18-76 months), seven have had complete resolution of their pain after this procedure. The technique failed in two patients, who each required two separate en bloc excisions with bone grafting to resolve each lesion. CT-directed CORB appears to be useful in localization and removal of the nidus of an osteoid osteoma.

Adolescent↗

PubMedDate not supplied

Relationship between femoral anteversion and osteoarthritis of the hip.

The purpose of this study was to establish a relationship between the magnitude of femoral anteversion and osteoarthritis of the hip. Sixteen osteoarthritic subjects were compared with 18 control subjects by an improved computed tomography (CT) scanning technique. Femoral anteversion was accurately determined with little radiation exposure. There was no significant difference in femoral anteversion between arthritic subjects and a "normal" control population. There was no significant difference in femoral anteversion between the involved and the uninvolved hips of these subjects with osteoarthritis. These results suggest that performing a derotational femoral osteotomy to prevent osteoarthritis is not indicated. The cause of primary osteoarthritis is multifactorial and does not depend solely on preexistence of higher femoral anteversion.

Aged↗

PubMedDate not supplied

Computed tomography in the measurement of femoral anteversion.

A new technique using computed tomography for measuring femoral anteversion is presented, with advantages over prior techniques. Computed tomography allows the visual portrayal of the cervical axis to be superimposed upon the diacondylar axis for direct goniometric measurement of the anteversion angle. Beyond its accuracy, the procedure requires no complicated positioning framework and can be done in a brief span of time.

Child, Preschool↗

PubMedDate not supplied

Angiographic assessment and control of potential operative hemorrhage with pathologic fractures secondary to metastasis.

Two cases are reported, which demonstrate the contribution of angiography to the operative management of neoplastic, pathologic fractures. The degree of fracture site neovascularity was assessed by pre-operative arteriography. Selective trans-catheter gelatin-foam embolization was then employed to markedly reduce or obliterate the arterial supply to lesions shown to be richly vascular. Open reduction and internal fixation was subsequently accomplished with minimal operative hemorrhage.

Adenocarcinoma↗