A radiographic review of 178 consecutive primary total hip arthroplasties using the AML femoral component with a mean follow up of 40.1 months identified 92.3% to be stabilized by bony ingrowth and 7.7% by fibrous tissue. None were classified as loose. The quality of fit in the isthmus and calcar regions was identified as an important factor in achieving bony ingrowth stabilization. Bony ingrowth was achieved in all age groups with equal frequency. No relationship between sex and the type of stabilization was identified. A clinical correlation utilizing a subset of patients with identical prosthetic components identified equivalent clinical results across all age groups. Thirty-four percent of patients experienced some residual thigh pain. No statistically significant relationship between the presence of thigh pain and the type of femoral component stabilization (bony vs fibrous) could be identified. Ninety-eight percent of patients expressed unconditional satisfaction with their hip replacements.
The halo cervical orthosis has proven extremely effective in stabilizing the spine, both non-operatively and as a supplement to operative procedures. Current designs of the available halo utilize either a closed or an open stabilizing ring. Twenty-four patients with various indications for halo application are reviewed. Eleven were treated with a closed ring apparatus (Ace Medical, Los Angeles, California), and thirteen with an open ring device (Bremer, Inc, Jacksonville, Florida). X-rays of the treated patients were compared by group, and patients were interviewed regarding their complaints while wearing the halo. Rates of complication were compared. Results showed no significant differences between radiographs (kyphosis or translation) throughout the follow-up period. Patients experienced a significantly higher incidence of halo-associated pain in the open group. Otherwise, there were no statistical differences in the complication rates of either device. Whether or not the higher incidence of pain in the open group is related to decreased device rigidity is unknown. The open design may theoretically permit bending and opening of the ring to occur, the so-called 'wishbone' effect. Based on these data, it cannot be determined whether the advantages of the open ring-ease of application-are offset by this potential disadvantage. Clearly, a larger, randomized prospective study is required to investigate this.
Hangman's fracture in ventrally flexed traction between 10(6) and 75 degrees is analyzed on the basis of 220 fracture trials on plaster of real bone preparations of the atlas and axis of two adults. Hangman's fractures, which are usually regarded as a form of injury from dorsal flexion, occurred in 25% of the fracture trials under this kind of strain. Frequency depended on flexion angle, as well as on inclination of the dens axis. Thus Hangman's fractures occurred, as a whole, more frequently in the kyphotic dens type than in the lordotic type and were found as a rule at 75 degrees flexion. Furthermore, the investigations showed that pedicles can by no means be regarded as the sole predilection site for fracture. A detailed description is provided on why the Hangman's fracture type, due to ventrally flexed traction, can be included in the group of bone injuries arising from flexion, with tensile stress of the dorsal parts of the dens and the corpus axis, on the one hand, and the upper side of the axis arch on the other. Hence, the injury picture ranges from the dorsal arch fracture to the horizontal rupture through the superior articular facies and the corpus axis, as documented by substantial evidence.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.