A comparison of 3-D CT and 2-D plain radiograph measurements of the wrist in extra-articular malunited fractures of the distal radius

Two-dimensional (2-D) plain radiographs may be insufficient for the evaluation of distal radial malunion, as it is a three-dimensional (3-D) deformity. This study introduced a 3-D measuring method that outputs radial inclination, ulnar variance, palmar tilt and axial rotation. To this end, a standardized and clearly defined coordinate system was constructed that allowed 3-D measurements closely resembling the conventional 2-D method in 35 patients. Mean differences between 3-D and 2-D measurements in affected wrists were 1.8° for radial inclination, 0.8 mm for ulnar variance and 3.7° for palmar tilt. In addition, inter- and intra-observer reproducibility of all 3-D and 2-D measurements were good or excellent (intraclass correlation coefficient >0.75), with 3-D reproducibility always better than 2-D. Axial rotation was present in all patients with a mean of 7.9° (SD 6.9). Although the differences between 2-D and 3-D measurements were small, 3-D evaluation enables the assessment of axial rotation and brings us closer to a routine 3-D evaluation of malunion.Level of evidence: III.

Outcomes of radialization with ulnar cuff osteotomy for radial longitudinal deficiency: a medium-term follow-up study

Addressing the deforming stresses arising from soft tissue and continued skeletal development is crucial to obtain long-term correction of forearm carpal alignment in Radial longitudinal deficiency. The aim of the present study was to report the medium-term follow-up results of radialization with ulnar cuff osteotomy in children. A total of 17 patients (21 involved limbs) with a mean follow-up of 66 months (range 50 to 96) were reviewed. Mean correction of the hand forearm angle at the final follow-up was 51°. Mean hand forearm position preoperatively and at the final follow-up were -1.1 cm (SD 0.9) and +1.3 cm (SD 0.8), respectively. This metaphyseal osteotomy relaxed the radial structures throughout the original phase of deformity correction. The mean ulnar growth was 62% of the contralateral side at the final follow-up. Our technique may provide a feasible solution to the correction and prevent recurrence of deformity while maintaining ulnar growth in the medium to longer term.Level of evidence: III.

Radiographic Assessment of Bilateral Asymmetry in the Upper Extremities of Living Humans

Objective Injuries resulting from trauma or tumor resection may cause length alterations in the bones of the upper extremities (UE) requiring reconstruction. Direct contralateral bone is often used to determine the appropriate length for reconstruction but fails to account for potential asymmetry. Given the paucity of data assessing asymmetry in living populations and the need for accurate length approximation, we developed a study evaluating UE long bone asymmetry using radiographic imaging in living subjects. Methods Bilateral X-ray images previously obtained for traumatic injury or chronic osseous conditions were retrospectively collected for adult subjects (ages 18-81). After screening, 61 patients met the inclusion criteria: 28 radii, 29 ulnae, and 19 humeri. Three serial measurements were taken, and the median was used for subsequent analysis. Wilcoxon signed-rank tests were performed to assess differences in contralateral bone lengths. Bootstrapping was utilized to obtain sample sizes of 200, 500, and 1000 for each bone. Results The difference in mean absolute length was 27.0 mm for the humerus, 8.6 mm for the radius, and 7.5 mm for the ulna. Neither the left side nor the right side was significantly longer for any bone. In 57.9% (11/19) of patients, the right humerus was longer than the left; in 60.7% (17/28), the right radius was longer than the left; and in 48.3% (14/29), the right ulna was longer than the left. All other measurements showed the left was longer than the right. Wilcoxon signed-rank tests did not find significant differences between contralateral pairs in any direct measurement group. In bootstrap samples, significant differences in length (p ≤ 0.05) were seen in all samples (n = 200, 500, and 1000) for both humerus and radius but only the 1000 sample group for the ulna. Conclusions Direct contralateral measure may be an appropriate method of length estimation for the humerus, radius, and ulna in post-industrial humans.

Predicting Body Height in a Pediatric Intensive Care Unit Using Ulnar Length

Objective: To determine if ulnar length obtained by the bedside nurse can be used to estimate patient length. To compare our findings to previous predictive equations of height and ulnar length. To evaluate the performance of predictive equations for height and ulnar length on patients with syndromes that affect height. Design: Retrospective observational study of prospectively collected data. Settings: Multidisciplinary Pediatric Intensive Care Unit in a university teaching hospital. Patients: 1,177 patients, ages 1 month to 23 years. Mean age was 79.7 months (1,3 IQR 19.5, 164.5 months) and 55.4% male. Measurements: Ulnar length was obtained using digital calipers by bedside nurses in PICU as well as height and weight. The electronic health care record was used to extract patient information. Main Results: The predictive equation for height for the entire group is: height (cm) = 0.59^*ulnar length (mm) + 13.1 (r² = 0.93). Bland Altman analysis of the derivation formula applied to the testing group did not show any systematic bias. Conclusions: Our study shows that ulnar length measurements can be used to predict height with a simple linear formula in a PICU setting. Not having specific individuals or specific training for ulnar measurement did not seem to alter the accuracy (r² = 0.93). The robust nature of the measurement and ease of use may make this an unconventional but reasonable alternative to obtaining height when that cannot be measured directly.