Radioulnar ratio in detection of distal radioulnar joint instability associated with acute distal radius fractures.

Lesions of the triangular fibrocartilage complex (TFCC) are commonly associated with distal radius fractures and may adversely affect the functional outcome. This prospective study evaluated computed tomography, using the radioulnar ratio (RUR), to detect laxity of the distal radioulnar joint in 48 consecutive patients with acute distal radius fractures and compared the results with a radioulnar stress test. We found the clinical stress test to be reliable in chronic cases, but the RUR method of questionable value in both acute and chronic cases.

A prospective comparison of Butel and PCA hip arthroplasty.

We compared two cementless femoral components, the 'isoelastic' Butel stem and the more rigid PCA design, in a randomised, prospective study of 56 patients with a mean follow-up of 4 years (2 to 5). Patients were matched in 28 pairs, and one of each pair was treated with each femoral component. The isoelastic stem gave fewer signs of stress shielding radiologically, but both the Harris hip score and the visual analogue pain scale showed significantly inferior results at the two-year and three-year follow-up. The overall failure rates for the femoral components were 43% for the Butel and 11% for the PCA. These results contrast with those of earlier experimental and clinical studies, in which isoelastic properties appeared to be advantageous. This review emphasises the importance of controlled studies before an altered or new design of prosthesis is released on to the market for general use.

Loosening 5 years after total hip replacement--a radiological study of the McKee-Farrar and Charnley prostheses.

In a prospective study, 138 patients who underwent total hip replacement by the McKee-Farrar or the Charnley technique were monitored yearly for 5 years by X-ray. Six variables were measured on anteroposterior and lateral projections to describe the position of the prosthesis. Lateral opening greater than 50 degrees and cover of the acetabular cup less than 1.5 cm correlated with an increased cup-loosening rate: 71% (98 of 138) were loose at the 5-year follow-up. However, only about one-third of all cup loosenings in the present series can be explained by nonoptimal position of the prosthesis. No significant difference emerged concerning loosening rate between the McKee-Farrar and the Charnley prostheses.

The stability of union in tibial shaft fractures: its measurement by a non-invasive method.

The stability of the union in tibial shaft fractures was followed by repeated non-invasive radiographic measurement of a deflection induced in the area of the fracture. By means of a Shift Comparator the difference in the angle between the two fragments before and during application of the deflecting force can be measured. The relative measure of the strength of the union is furnished by a quantity, the deflection ratio, which is based on the quotient of the induced deflection by the magnitude of the applied bending moment. When this ratio falls below a certain value the union is considered to be stable enough for full weight bearing during walking. A plot of the deflection ratio against time, with logarithmic scales on both axes had a negative slope and was more or less linear. This graph can serve as an aid in detecting the course of union, in deciding when the cast should be removed, and in detecting any irregularity in the process of union. In the management of 207 fractures of the tibial shaft 508 such deflection measurements were performed.

Serial bone scanning of Colles fracture.

Serial bone scannings with 99-M-Tc-MDP have been performed in 15 patients with an extra-articular dorsal-angulated fracture of the distal radius (Colles' fracture). A method for the quantification of healing activity is described. The activity-ratios show a typical pattern of progress during the healing period. There is a correlation between fractures with high activity ratios late in the healing period and fractures that redisplace during the healing period.