Face Injury from Jamming in a Power-Operated Window of a Motor Vehicle: A Case Report

Introduction: Automatic power-operated windows of modern motor vehicles present a risk of injury due to jam events. Case Report: A 41-year-old man suffered an injury of his gingiva upon jamming of his face between the window and seal entry. The motor vehicle window that led to the injury had no closing force restriction. Discussion: Equipping power-operated windows with closing force restriction should be required

Analysis of Fit of the Ascension (R) PyroCarbon PIP Total Joint Component Heads

Background: The Ascension pyroCarbon proximal interphalangeal (PIP) total joint is available in 4 different sizes, and ideally, the prosthesis head will be flush with the bone. Fit of the Ascension pyrocarbon PIP joint prosthesis has not yet been investigated. Materials and Methods: The components of the Ascension pyrocarbon PIP total joint were inserted in 287 phalanges of human cadaver specimens. The distances from the edge of the component head to the edge of the bone were electronically measured radially, ulnarly, dorsally and palmarly on radiographs in posterior-anterior and lateral views. Results: Only one finger had a precise fit of the heads of both, the proximal and corresponding distal component in relation to the bone. Only in 17 (5 proximal, 12 distal) prosthesis components the head did the bone fit on all sides. Overall, the proximal component head tends to be too large, while the distal component head tends to be too small. Conclusion: With occasional exceptions, the proximal and distal component heads of the Ascension pyrocarbon PIP total joint do not accomodate the dimensions of finger phalanges

Analysis of the Design of the Ascension (R) PyroCarbon PIP Total Joint Proximal Component in Relation to the Proximal Phalanx Morphology

Background: There are many indications that long-term stability of the Ascension((R)) pyrocarbon proximal interphalangeal (PIP) total joint is not attained by osseointegration but by appositional bone formation. Accordingly, good locking by cortical bone for sufficient primary stability is necessary in order to avoid prosthesis loosening before enough new bone has been formed. The size of the proximal component of the Ascension((R)) PyroCarbon PIP total joint and thus cortical anchorage and primary stability depend on the morphology of the proximal finger phalanx and, especially, on the isthmus of the distal medullary canal. Objective: To clarify whether the medullary canal of the proximal finger phalanx can be enlarged using the Ascension((R)) pyrocarbon PIP total joint instruments so that cortical contact of the proximal prosthesis component is guaranteed in the region of the isthmus in both sagittal and frontal planes. Material und Methoden: Before insertion of the Ascension((R)) pyrocarbon PIP total joint prosthesis, the isthmus widths of the proximal phalanx of 138 cadaver fingers were measured on radiographs by fluoroscopy in both the frontal and sagittal plane. The measured dimensions were compared to the dimensions of the inserted proximal component stems (manufacturers instructions) after preparation of the medullary canal. The largest prosthesis possible was always used. Results: The mean isthmus width of the index fingers on PA view was 3.4mm (2.4-4.2), of the middle fingers 3.3mm (1.8-4.6), of the ring fingers 3.2mm (2.2-4.7), and of the small fingers 2.9mm (1.4-4.3). The mean isthmus width of the index fingers on lateral view was 2.6mm (1.6-3.7), of the middle fingers 2.5mm (1.8-3.8), of the ring fingers 2.3mm (1.5-3.6), and of the small fingers 2.0mm (1.4-2.8). There were statistically significant differences between the isthmus widths measured before insertion and the stem dimensions of the inserted proximal components. While the average width of the isthmus in the index, middle, ring, and little fingers was significantly larger than the stem width of the inserted proximal components, the average isthmus height was significantly smaller than the stem height of the inserted proximal components. Conclusion: Ideal cortical contact between the isthmus of the proximal phalanx and the largest proximal component of the Ascension((R)) pyrocarbon PIP total joint prosthesis that can be inserted, and thus good primary stability, is not possible due to a mismatch in the frontal plane between the morphology of the proximal phalanx and the prosthesis. But good contact can be achieved in the sagittal plane by broaching the medullary canal