D Campbell

Metastatic pulmonary ameloblastoma. An unusual case.

We present a patient who had a large metastatic pulmonary ameloblastoma resected 25 years after removal of an apparently benign primary ameloblastoma of the jaw. It highlights three areas: problems with the histopathological diagnosis of pulmonary metastases using fine needle aspiration; a noted radiological improvement after a 5-year course of oral cyclophosphamide, in keeping with occasional patients who have responded to chemotherapy; and the technical difficulties of resection of a large pulmonary metastasis, particularly when it is adherent to the mediastinum.

How Critical is Patient Positioning in Radiographic Assessment of the Hip in Cerebral Palsy When Measuring Migration Percentage

Background: Migration percentage (MP) is an accepted method of assessing lateral displacement of the femoral head in children with cerebral palsy (CP). Difficulty in positioning of patients for pelvic radiography remains a concern for the reliability of the MP. Methods: This 2-part quantitative study examined 100 anteroposterior pelvic radiographs for children with CP. Fifty were from a region that had a positioning protocol for hip surveillance of children with CP and 50 images were from a region without. Images were assessed for acceptability of position in relation to hip abduction/adduction and/or pelvic rotation. Ten images deemed Acceptable or Borderline from the region with no protocol were then randomly selected. MP was measured on 2 separate occasions by 5 children’s orthopaedic surgeons and statistically analyzed for intrarater and interrater reliability. Results: There was no statistically significant difference in the acceptability of images between the 2 regions with 60% to 66% of the images meeting the criteria outright. When allowances were made for slight variation of abduction/adduction within 5 degrees, 74% to 80% of the images were acceptable. Reliability was variable with limits of agreement between 4.96% and 15.15%. Observers more familiar with the software measuring package had higher reliability within and between occasions. Variability within and between observers decreased as MP increased. Conclusions: Poor positioning did not appear to be the main reason for the variation in reliability of MP. Repeat measurements were reliable although standardized technique, training, and familiarity with software measuring programmes did influence outcomes. Level of Evidence: This is a Level I diagnostic study divided into 2 parts. The first half is a retrospective study of pelvic radiographs of children with CP as part of their annual/biannual orthopaedic assessment. The second half is an interrater and intrarater reliability study of MP measurement.

Cozen's phenomenon: a reminder.

A four-year-old child attended Accident and Emergency following a fall from a slide with a displaced and angulated proximal tibial metaphyseal fracture. Treatment included closed manipulation under anaesthesia and an above knee cast for seven weeks. Serial radiographs over the following few months were satisfactory demonstrating good alignment and evidence of healing. However, at four-months review new-onset genu valgum with mechanical axis deviation was noted. No evidence of spontaneous resolution was noted over the following 12 months and hence a corrective hemi-epiphysiodesis was performed. At 12-months post-operatively, there was marked clinical and radiographical improvement in alignment. Classically Cozen’s phenomenon is described as the late-onset post-traumatic valgus deformity associated with proximal tibial metaphyseal fractures in children. We want to reemphasise the early recognition of children at risk of this unique complication. In addition, we wish to highlight the progression of the late-onset valgus and its subsequent management.

A simple modification of the Pavlik harness for unstable hips.

The Pavlik harness has been used in the treatment of developmental dysplasia of the hip for almost 60 years. During this time there has been little in the way of modification of the original design. In clinical practice it has an established role, but it is recognized to be less effective in more unstable hips, which are often associated with marked acetabular dysplasia. The authors present a simple modification that proved successful in three hips that were not stabilized in a Pavlik harness applied in the usual fashion.

Prophylactic pinning for slipped capital femoral epiphysis: does it affect proximal femoral morphology?

This study was designed to determine whether prophylactic pinning of the unaffected hip in unilateral slipped capital femoral epiphysis affects the proximal femoral morphology. Twenty-four hips prophylactically pinned were compared with 26 cases observed. The articulotrochanteric distance (ATD) and the trochanteric–trochanteric distance (TTD) were measured. Postoperative radiographs were compared with final follow-up radiographs. The final TTD : ATD ratio was higher (P=0.048) in the pinned group, suggesting relative coxa vara/breva. There was a smaller difference between the two hips in the prophylactically pinned group (0.7) as opposed to those observed (1.47). Prophylactic pinning does not cause growth to stop immediately but alters the proximal femoral morphology.