Measurement Of Ulnar Variance Research Articles

Reliability of Wrist Arthroscopy in the Diagnosis and Treatment of Triangular Fibrocartilage Complex Tears

Wrist arthroscopy is considered the gold standard for diagnosis of intra-articular wrist conditions including triangular fibrocartilage complex (TFCC) tears; however, the ability to reliably diagnose TFCC pathology during wrist arthroscopy is unclear. The purpose of this study was to assess the reliability of the diagnosis of TFCC tears on wrist arthroscopy videos. Five hand surgeons reviewed 43 cases on a secure web-based platform at two time points separated by 4-6 weeks. Each case included a deidentified clinical vignette and wrist radiographs with ulnar variance measurements and an arthroscopy video of ulnar wrist pathology, averaging 42 seconds. Surgeons were queried on the presence of TFCC tear and Palmer and Atzei classifications. Interobserver/intraobserver reliabilities were determined using kappa coefficients. The interobserver reliability regarding the presence/absence of TFCC tear was fair-good, with kappa coefficients of 0.596 in the first round of case review and 0.708 in the second round. The overall intraobserver reliability for the presence/absence of TFCC tear was also fair-good, with a kappa coefficient of 0.567. For cases with central TFCC tears, the interobserver reliability regarding the presence of TFCC tear was perfect, with a kappa coefficient of 1.0. When central tears were excluded, the kappa coefficients decreased to 0.322 and 0.368 in each round. The interobserver reliability for the Palmer and Atzei classifications was low, with kappa coefficients of 0.220 and 0.121 in the first round and 0.222 and 0.123 in the second round. Experienced wrist arthroscopy surgeons demonstrated fair-good interobserver reliability for the diagnosis of TFCC tear on wrist arthroscopy. However, when central TFCC tears were excluded, interobserver reliability was poor. These findings demonstrate a need for a focus on education for wrist arthroscopy anatomy. This investigation demonstrated poor agreement in surgeon identification and classification of TFCC tears, aside from central TFCC tears. The low reliability has a direct bearing on treatment considerations for TFCC tears.

Comparison of cone beam computed tomography and plane radiographs of radial fractures as a basis for radiographical measurements

BackgroundThe purpose of this study was to determine whether radiological measurements of radial fracture position made in cone beam computed tomography (CBCT) projection images are comparable to those made on traditional radiographs and could potentially substitute them.MethodsSixteen patients with fractures of the distal radius referred for radiographs were recruited for an additional CBCT scan which was performed immediately afterwards. Projection images and volumetric data were saved from the CBCT scans. Measurements of ulnar variance, radial inclination and volar tilt were made from all three sets of images.ResultsAgreement of projection image based measurements with radiographs was nearly as good as as the agreement of cross sectional image measurements with radiographs. The average difference between the results for projection images and radiographs were -1.2 mm (SD 1.9 mm), for radial inclination 0.7° (SD 2.9°) and for volar tilt 1.9° (SD 5.6°).ConclusionDifferences between radiological measurements between the modalities studied are small and projection images could be used for the assessment of distal radial fractures.

Dorsal Tilt of the Distal Radius Fracture Changes With Forearm Rotation When Measured on Radiographs

PurposeThis study examined the impact of pronation and supination on the reliability of the radiographically measured values of dorsal tilt, radial inclination (RI), and ulnar variance (UV) in cadaveric forearms with artificially created distal radius fractures.MethodsWe prepared 21 human cadaveric forearms (11 right and 10 left) for radiostereometric analysis (RSA) by insertion of tantalum markers. Distal radius fractures were created midway between the marker segments. Radiographs and RSA images were taken at different degrees of supination and pronation. The precise degree of forearm rotation was calculated using RSA software. Two observers (H.B.T. and T.T.) independently measured tilt, RI, and UV on all radiographs in a blinded and randomized fashion. Univariate linear regression analyses were used to determine the relationship between forearm rotation and the measured radiographic values.ResultsThe radiographically measured value of tilt was significantly impacted by forearm rotation. Supinating or pronating the forearm by 10° decreased and increased, respectively, the radiographic value of dorsal tilt by approximately 3°.ConclusionsThis study showed that the positioning of the fractured forearm during the radiographic procedure significantly impacted subsequent radiographic measurements of tilt. Dorsal tilt measurements increased (ie, fracture displacement measured more dorsal) with pronation and decreased (ie, fracture displacement measured more toward neutral, with less dorsal tilt) with supination of the forearm. However, measurements of RI (p = 0.12 and p = 0.55 for observer 1 and 2) and UV (p = 0.34 and p = 0.17, observer 1 and 2) were not significantly impacted by rotation.Clinical relevanceTreatment of a distal radius fracture is, at least to some extent, based on radiographic quantification of fracture deformity. Therefore, unreliable measurements may adversely influence clinical decision making.

Temporary epiphysiodesis in adolescent patients with ulnocarpal impaction syndrome: a preliminary case series of seven wrists.

Adolescents with ulnar positive variance can develop ulnocarpal symptoms due to ulnocarpal impaction syndrome. Common treatment methods are conservative therapy, distal ulna epiphysiodesis or eventually ulnar shortening osteotomy. The aim of this preliminary case series was to investigate a recently described, new therapeutic approach using a reversible, temporary epiphysiodesis technique, following the principles of guided growth. Seven cases with the diagnosis of a painful ulnar positive variance, which underwent a temporary epiphysiodesis, were retrospectively evaluated. These cases consisted of four individual patients who received an intraoperatively customized plate fixation to slow down growth. The following parameters were collected: diagnosis, age at surgery, age at explantation, growth plate status at explantation, ulnar variance before and after surgery, complications and any clinical and radiological abnormalities. The radiological measurements of ulnar variance were performed according to the Gelbermann method. The seven investigated cases (average age at surgery 12.4 years; average age at explantation 14.7 years), in which a temporary epiphysiodesis was performed, showed an average ulnar variance of +3.9 mm (range: from +1.9 mm to +6.1 mm) before the start of therapy. After explantation, an average ulnar variance of +0.1 mm (range: from –3.2 mm to +5.0 mm) was observed, which corresponds to an average reduction/improvement of –3.8 mm (range: from –0.5 mm to –9.3 mm). The ulnocarpal wrist complaints were significantly reduced after the intervention. One case needed a secondary ulnar shortening osteotomy. The described method of a temporary, reversible epiphysiodesis is an elegant, less invasive technique to correct the ulnar positive variance without irreversibly closing the growth plate. In case of therapy failure, a secondary ulna shortening osteotomy is still possible.

Three-Dimensional Automated Assessment of the Distal Radioulnar Joint Morphology According to Sigmoid Notch Surface Orientation

To develop reproducible 3-dimensional measurements for quantification of the distal radioulnar joint (DRUJ) morphology. We hypothesized that automated 3-dimensional measurement of the ulnar variance (UV) and the sigmoid notch (SN) angle would be comparable to those of the reference standard while overcoming some drawbacks of conventional 2-dimensional measurements. Radiological data of healthy forearm bones (radiographs and computed tomography) of 53 adult subjects were included in the study. Automated measurements were developed for assessment of the SN morphology based on 3-dimensional landmarks, incorporating subject-specific estimation of cartilage surface orientation. A common anatomical reference was defined among the different imaging modalities and a comparison of the SN angle and UV measurements was performed in radiographs, computed tomography scans, and 3-dimensional models. Finally, the 3-dimensional UV measurements were evaluated in an experimental setup using 3-dimensional printed bone models. The automated 3-dimensional measurements of SN subtypes showed a notably larger notch radius (18.9 mm) for negative SN angles compared with positive SN angles in subjects (16.9 mm). Similar UV measurements were obtained in healthy DRUJ morphologies, with a high correlation between radiographs and 3-dimensional measurements for the SN angle (0.77) and UV (0.85). In the experimental setup with pathological radial inclinations, UV was on average 1.13 mm larger in the radiographs compared with the 3-dimensional measurements, and 1.30 mm larger in the cases with pathological palmar tilts. Furthermore, UV radiograph measurements on the modified palmar tilt deviated from the 3-dimensional measurements. The developed 3-dimensional automated measurements were able to quantify morphological differences among sigmoid notch subtypes and were comparable to those of the reference standard. The developed methods do not depend on the forearm position or orientation of the distal radius and can be used for 3-dimensional quantification of DRUJ pathologies in 3-dimensional surgical planning.

Improved precision of radiographic measurements for distal radius fractures after a technique-teaching tutorial.

For the management of distal radius fractures, surgical decision-making depends on radiographic measurements of indicators including radial inclination (RI), ulnar variance (UV) and radial tilt (RT). Evaluation of the inter- and intrarater reliability of surgeons' measurements of these criteria has been limited. Twelve physicians were invited to participate in this study. Anonymously, they measured RI, UV and RT on 30 digitally stored radiographs of distal radius fractures on 3 occasions, each at least 1 week apart, using online measuring tools. After taking the third set of measurements, the participants were given a tutorial by the senior author (G.J.) on a single technique to measure all 3 indicators. The participants then took 3 more sets of measurements using only the technique they had been taught. Intraclass correlation coefficients (ICCs) were used to evaluate interrater reliability each week. Multiple logistic regression was used to calculate the effect of the tutorial, controlling for week of study along with reader (participant) and patient variance. The ICCs indicated that the participants' measurement precision improved promptly after the tutorial, and this improvement was sustained through subsequent readings. The odds of an "accurate" measurement (within 2° of the senior author's measurements for RI, 1 mm for UV and 4° for RT) was 1.7 times higher for RI, 2.7 times higher for UV and 2.3 times higher for RT after the tutorial; all of these results were statistically significant. Surgeons ought to be familiar with a method to reproducibly measure the indicators used in the published guidelines for surgical intervention. The tutorial on a single standardized technique for online measurement of RI, UV and RT in distal radius fractures improved measurement precision.

Three-Dimensional Versus Radiographic Measurements for Analyzing Extra-Articular Distal Radius Malunion

To compare the accuracy of evaluating deformity in distal radius malunions using plain radiographic measurements compared with a 3-dimensional method involving 3-dimensional computer bone models. Consecutive patients who had an extra-articular distal radius malunion were included. Standard radiographs and computed tomography scans of both wrists were performed. Palmar tilt, radial tilt, and ulnar variance were measured on radiographs. The computed tomography scan data were sent to a workstation and 3-dimensional bone surface models of the radius were created. The 3-dimensional palmar tilt, 3-dimensional radial tilt, 3-dimensional ulnar variance, and axial rotational deformity were calculated. Thirteen patients, mean age 40 years (range, 22-57 years) were included. The 3 3-dimensional values were positively correlated with their corresponding radiographic values. Nevertheless, the 3-dimesional palmar tilt and 3-dimensional radial tilt values were slightly smaller than the radiographic palmar tilt and radial tilt. The quantitative difference between the 3-dimensional method and plain radiographs was on average 2° for the dorsal deformity group and 3° for the palmar deformity group. The 3-dimensional ulnar variance was significantly higher than the radiographic ulnar variance by an average of+1.3 mm for malunions with dorsal tilt and+0.6 mm for malunions with palmar tilt. The 3-dimensional method allowed us to measure the extent of the axial rotational deformity, which was 9° on average (range, 2° to 21°). Despite small differences, measurements made on both plain radiographs and 3-dimensional computer bone models are accurate for evaluating the deformity in extra-articular distal radius malunions. Our 3-dimensional method seems to provide a more accurate measurement of ulnar variance, particularly for dorsally angulated cases, and is helpful for measuring rotational malalignment. In this study, we found that either a 3-dimensional computer bone model or plain radiographs can be used as a benchmark to evaluate the deformity of extra-articular distal radius malunion. The 3-dimensional method can also be used to define axial rotational deformity.

Radial Reference Points for Measuring Palmar Tilt and Ulnar Variance on Lateral Wrist Radiographs.

Background: Palmar tilt and ulnar variance are crucial parameters for evaluating the distal radius. Identifying suitable reference points for these parameters on lateral wrist radiographs remains challenging. The purpose of this study was to establish reference points for measuring palmar tilt and ulnar variance on lateral wrist radiographs and to evaluate the reliability of these two parameters using the newly defined reference points. Methods: The distal articular surfaces of 25 cadaver radii were marked at four different locations using thin wires. These bones were radiographed and constant landmarks were recorded. The reliability of the palmar tilt and ulnar variance measurements was assessed using the new reference points and two serial measurements recorded by three observers on 27 standardized lateral wrist radiographs. Results: The reference points for palmar tilt on lateral radiograph were the dorsal and volar end points of the subchondral line. The subchondral line was connected to two of five metaphyseal cortical lines. The reference point for lateral ulnar variance was easily defined on the midpoint of the proximal aspect of the subchondral line. The corresponding posteroanterior central reference point for ulnar variance was at the ulnar corner of the subchondral line. Inter- and intra-observer reliabilities were overall good for the palmar tilt measurements, and excellent for the ulnar variance measurements. Conclusions: Palmar tilt can be determined accurately with a good understanding of the radiographic landmarks on lateral radiographs, and by addressing the problems caused by ulnar inclination of the articular surface of the distal radius. Lateral wrist radiographs can provide a complete picture of the ulnar border of the radius for measuring ulnar variance.

Measurement of Ulnar Variance in Indian population

Measurement of Ulnar Variance in Indian population

Well-founded practice or personal preference: a comparison of established techniques for measuring ulnar variance in healthy children and adolescents

ObjectivesUlnar variance is a clinical measure used to determine the relative difference in length between the radius and ulna. We aimed to examine consistency in ulnar variance measurements and normative data in children and adolescents using the perpendicular and the Hafner methods.MethodsTwo raters measured ulnar variance on hand radiographs of 350 healthy children. Participants’ mean calendar and skeletal ages were 12.3 ± 3.6 and 12.0 ± 3.7 years, 52% were female. Raters used the perpendicular method, an adapted version of the perpendicular method (in which the distal radial articular surface is defined as a sclerotic rim) and the Hafner method, being the distance between the most proximal points of the ulnar and radial metaphyses (PRPR) and the distance between the most distal points of both (DIDI). Intraclass correlation coefficients (ICCs) for intermethod consistency and inter- and intrarater agreement were calculated using a two-way ANOVA model. Variability and limits of agreement were determined using the Bland-Altman method.ResultsThe interrater ICC was 0.75 (95% CI, 0.61–0.84) for the adapted perpendicular method, 0.88 (95% CI, 0.80–0.93) for PRPR, and 0.94 (95% CI, 0.90–0.97) for DIDI. The intermethod consistency ICC was 0.60 (95% CI, 0.48–0.70) for perpendicular versus PRPR and 0.60 (95% CI, 0.49–0.70) for perpendicular versus DIDI. The intrarater ICC was 0.88 (95% CI, 0.70–0.95) for perpendicular, 0.90 (95% CI, 0.83–0.94) for PRPR, and 0.81 (95% CI, 0.69–0.89) for DIDI. The perpendicular method was not useable in 38 cases (skeletal age ≤ 9 years) and the Hafner method in 79 cases (skeletal age ≥ 12 years).ConclusionsThe perpendicular and Hafner methods show moderate intermethod consistency. The Hafner method is preferred for children with skeletal ages < 14 years, with good to excellent inter- and intrarater agreement. The adapted perpendicular method is recommended for patients with skeletal ages ≥ 14 years.Key Points• The perpendicular method for measuring ulnar variance requires extended instructions to ensure good interrater agreement in pediatric and adolescent patients.• The Hafner method is recommended for ulnar variance measurement in children with unfused growth plates and up to a skeletal age of 13 years, and the perpendicular method is recommended for children with fused growth plates and from skeletal age 14 and older.• The mean ulnar variance measured in this study for each skeletal age group (range, 5–18 years) is provided, to serve as a reference for future ulnar variance measurements using both methods in clinical practice.

Distal radius fractures and radiographic assessment: a systematic review of measurement accuracy.

Background Distal radius fracture characterization and treatment are mainly based on radiographic measurements but with contradictory findings on the correlation of those measurements to clinical outcome. Before applying radiographic measurement to the treatment decision and before correlating the measurements to clinical outcome, an accuracy of measurements must be established. Purpose To summarize existing evidence on accuracy of the radiographic measurements of: (i) dorsal/volar tilt of the distal radius; (ii) radial shortening; (iii) ulnar variance; (iv) radial inclination; and (v) articular step-off of the distal radius. We conducted a systematic critical review of the literature. Material and Methods MEDLINE, EMBASE, and the Cochrane Library database were searched. The Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines were followed. Quality of included studies was assessed using a tailored version of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Results A total of 5908 publications were screened and five studies met the inclusion criteria. Four studies assessed accuracy of articular step-off but with contradictory outcomes. Radiographic measurements of step-off were accurate in two studies and inaccurate in one study. In the last step-off study, some of their measurements varied significantly but accuracy was not reported. The radiographic measurements of ulnar variance were significantly underestimated when compared to the true variance. We were not able to include studies that assessed accuracy of radial shortening, radial inclination, or dorsal/volar tilt against a reference standard. Conclusion Currently, evidence is not available to support accuracy of the radiographic measurements commonly used to characterize distal radius fractures.

Ulnolunate Distance and Lunate Height: Reliability Testing

Many methods for measuring ulnar variance have been described. The purpose of thisstudy was to introduce the use of both lunate height and ulnolunate distance on the zero-rotation view as well as to assess the intra- and interobserver reliabilities of these measurements. The hypothesis was that the use of concave surfaces in the measurement of both lunate height and ulnolunate distance will yield a higher intra- and interobserver reliability than ulnar variance, which uses the convex surface of the distal radius. Seven hand fellows reviewed 32 radiographs. Measurements of lunate height, ulnolunate distance, and ulnar variance, using the method of perpendiculars, were recorded to the nearest 0.5 mm. Intraclass correlation coefficient (ICC) was then calculated for each radiograph for intra- and interobserver reliability. The ICC measurements were similar for lunate height, ulnolunate distance, and ulnar variance. The inter- and intraobserver reliability was similar for all 3 measurements. Measurements of ulnar variance utilize the concave surface of the distal radius. The use of the convex surface of the lunate and pole of the ulna does not seem to improve the reliability of these measurements. Further studies are necessary to confirm the clinical utility of these measurements. The use of ulnolunate distance and lunate height as an adjunct to ulnar variance may assist in evaluation of distal radius fractures and ulnocarpal abutment, improve surgeon communication, and contribute to our overall knowledge of the wrist.

Relationship Between Ulnar Variance, Cortical Bone Density, and Load to Failure in the Distal Radius at the Typical Site of Fracture Initiation

Increased ulnar variance has been shown to lead to diminished load borne by the distal radius. The purpose of this study was to determine the correlations among ulnar variance, bone mineral density, and load to failure at the distal radius. Posteroanterior radiographs and computed tomographic scans were taken of 12 cadaveric forearms in neutral rotation. Ulnar variance was measured for each wrist by the method of perpendiculars. Measurements of cortical, trabecular, and combined bone density were made at the distal radius. We performed linear regression analysis and correlation analysis to determine the relationship between bone densities and ulnar variance measurements. Next, we loaded the 12 cadaveric radii to failure under axial compression. Linear regression analysis and correlation analysis were then performed to determine the relationship between load to failure and both ulnar variance and cortical density. Increased ulnar variance was significantly correlated with decreased cortical bone density at the distal radius and both were correlated with decreased load to failure. We found no correlation between ulnar variance and trabecular density or combined trabecular and cortical bone density at the distal radius. Our study found that increased ulnar variance and decreased cortical bone mineral density correlates with decreased load to failure under axial compression. Ulnar variance is linked to both bone quality and load to failure at the distal radius.

Negative Ulnar Variance and Kienböck Disease

To test the primary null hypothesis that there is no difference in mean ulnar variance (UV) scaled to the length of the capitates between 166 wrists with Kienböck disease and an equal number of matched controls and to test the secondary null hypothesis that mean scaled UV does not vary based on age, sex, or race in both Kienböck and control wrists. Ulnar variance was measured on posteroanterior radiographs of the wrist as the distance between a line through the midpoint between the volar and the dorsal edges of the ulnar margin of the radius and a line tangential to the most distal aspect of the carpal surface of the head of the ulna, both perpendicular to the longitudinal axis of the radius. Measurement of UV was scaled to the length of the capitate, resulting in a UV to capitate height (UV:CH) ratio. We found a significant difference in mean UV:CH ratio between patients with Kienböck disease and a control group matched by age, sex, race, and limb. The prevalence of negative UV was high in both patients with Kienböck disease and matched controls. There were no differences in mean UV:CH ratio with respect to age, sex, or race among patients with Kienböck disease or matched controls. The precise role of ulna minus in the development of Kienböck disease remains uncertain and unanswered, given that many patients with Kienböck disease have neutral or positive UV. In addition, a large proportion of the normal population has negative UV, whereas Kienböck disease is rare.

Measurement of Ulnar Variance in a Regional Subset of Indian Population-A Pilot Study of 30 Subjects.

The variation of level of distal articulating surface of ulna with respect to distal articulating surface of radius is known as ulnar variance (UV). Positive and negative UV has been implicated in various wrist and hand pathologies. To measure ulnar variance in a regional subset of Indian population and to compare two techniques of measurement of ulnar variance viz. method of perpendiculars and modification of the concentric circles method. UV was measured in a regional subset of Indian population comprising of 30 subjects. The mean age of patients was 35.9 years. There were 16 males and 14 females in the study group. Antero-posterior (AP) X-rays of wrist in neutral position were taken and UV was measured using method of perpendiculars and the modified circle method. The mean UV using method of perpendiculars (UVA) was 0.387 mm and using modified circle method (UVB) was 0.507mm. A higher predominance of positive UV in this regional subset of Indian population was observed. There was no correlation between UV with respect to age and sex. No statistically significant difference was observed between the two methods of measurement utilized in the study. The documentation of a negative and positive ulnar variance will help in prophylactic and timely intervention for various wrist pathologies, if required. However, a larger sample size with a longer follow up is required to suggest a correlation of ulnar variance with clinically symptomatic disease.

Commentary on Kawanishi et al. 'A comparison of 3-D computed tomography versus 2-D radiography measurements of ulnar variance and ulno-lunate distance during forearm rotation'.

Commentary on Kawanishi et al. 'A comparison of 3-D computed tomography versus 2-D radiography measurements of ulnar variance and ulno-lunate distance during forearm rotation'.

Measurement of Ulnar Variance From the Lateral Radiograph: A Comparison of Techniques

To determine the reliability of measuring ulnar variance on lateral wrist radiographs and to compare this technique with previously described methods. Ulnar variance was measured in 100 normal wrist radiographs using the methods of perpendiculars, central reference point, and the lateral radiograph by 3 surgeons on 2 occasions. Intraobserver repeatability and agreement between raters and methods were assessed and compared. Intra- and interobserver reliability and agreement were both excellent using all 3 methods within a ± 1.0-mm cutoff. However, there was substantial pairwise disagreement in measures of ulnar variance between all 3 methods. This study demonstrates that, for measurement of ulnar variance, the methods of perpendiculars, central reference point, and lateral radiographic measurement each have clinically acceptable intraobserver repeatability and interobserver agreement. Despite their independent reliability, each method of radiographic determination of ulnar variance had considerable disagreement with the other methods, indicative of inherent inaccuracies in the techniques. The lateral radiograph uniquely allows for visualization of the amount of ulnar head protruding proximal or distal to the concave lunate facet and allows for a rapid estimation of pronosupination, which is known to affect ulnar variance. Determination of ulnar variance can be an important component of surgical decision making in various pathological conditions of the hand and wrist. Traditionally, it has been measured through methods using the posteroanterior wrist radiograph, but there are potential shortcomings with these methods, and use of the lateral radiograph may provide a more clinically relevant picture of ulnar variance. This study shows that measurement from the lateral radiograph provides similar reliability to previously accepted techniques.

A comparison of 3-D computed tomography versus 2-D radiography measurements of ulnar variance and ulnolunate distance during forearm rotation

Positive ulnar variance is associated with ulnar impaction syndrome and ulnar variance is reported to increase with pronation. However, radiographic measurement can be affected markedly by the incident angle of the X-ray beam. We performed three-dimensional (3-D) computed tomography measurements of ulnar variance and ulnolunate distance during forearm rotation and compared these with plain radiographic measurements in 15 healthy wrists. From supination to pronation, ulnar variance increased in all cases on the radiographs; mean ulnar variance increased significantly and mean ulnolunate distance decreased significantly. However on 3-D imaging, ulna variance decreased in 12 cases on moving into pronation and increased in three cases; neither the mean ulnar variance nor mean ulnolunate distance changed significantly. Our results suggest that the forearm position in which ulnar variance increased varies among individuals. This may explain why some patients with ulnar impaction syndrome complain of wrist pain exacerbated by forearm supination. It also suggests that standard radiographic assessments of ulnar variance are unreliable.

Distraction Plating for the Treatment of Highly Comminuted Distal Radius Fractures in Elderly Patients

To evaluate internal distraction plating for the management of comminuted, intra-articular distal radius fractures in patients greater than 60 years of age at two level 1 trauma centers. We specifically desired to determine whether patients would have acceptable results from the clinical standpoint of range of motion, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and the radiographic measurements of ulnar variance, radial inclination, and palmar tilt. Our hypothesis was that distraction plating of comminuted distal radius fractures in the elderly would result in acceptable outcomes regarding range of motion, DASH score, and radiographic parameters and would, thereby, provide the upper extremity surgeon with another option for the treatment of these fractures. A retrospective review was performed on 33 patients over 60 years of age with comminuted distal radius fractures treated with internal distraction plating at two level 1 trauma centers. Patients were treated with internal distraction plating across the radiocarpal joint. At the time of final follow-up, radiographs were evaluated for ulnar variance, radial inclination, and palmar tilt. Range of motion, complications, and DASH scores were also obtained. We treated 33 patients (mean age, 70 y) with distraction plating for comminuted distal radius fractures. At final follow-up, all fractures had healed, and radiographs demonstrated mean palmar tilt of 5° and mean positive ulnar variance of 0.6 mm. Mean radial inclination was 20°. Mean values for wrist flexion and extension were 46° and 50°, respectively. Mean pronation and supination were 79° and 77°, respectively. At final follow-up, the mean DASH score was 32. In the elderly, distraction plating is an effective method of treatment for comminuted, osteoporotic distal radius fractures. Therapeutic IV.

Ulnar Variance: Correlation of Plain Radiographs, Computed Tomography, and Magnetic Resonance Imaging With Anatomic Dissection

Several techniques used to measure ulnar variance on a posteroanterior wrist radiograph have been described. It remains unclear whether they accurately represent the true ulnar variance of the patient. The purpose of this study was to correlate ulnar variance measurements on plain radiographs, computed tomography (CT), magnetic resonance imaging (MRI), and anatomic dissection. Posteroanterior (PA) radiographs, coronal and sagittal CT scans, and coronal MRI scans were obtained on 8 fresh-frozen cadaver wrists. The ulnar variance was measured by 5 reviewers. The specimens were then dissected, exposing the wrist joint. The ulnar variance was measured directly on each specimen using digital calipers. The inter-rater reliability was calculated for each imaging modality. The bias for each imaging modality was calculated using the digital caliper measurements as the true ulnar variance. Intraclass correlation coefficients demonstrated excellent inter-rater reliability for each imaging modality. The average bias from the true variance was the following: PA radiograph, 0.77 mm; coronal CT, 0.96 mm; sagittal CT, 0.96 mm; MRI with articular cartilage, 0.73 mm; MRI excluding cartilage, 0.49 mm. The variance measured on all imaging modalities tended to underestimate the magnitude of the true variance. Ulnar variance measured on coronal MRI best reflected the true ulnar variance as measured directly using calipers. The CT scans demonstrated the greatest deviation from the true variance. However, differences were small and might not be clinically meaningful. All imaging modalities demonstrated excellent inter-rater reliability, with MRI being highest. All imaging modalities tended to underestimate the magnitude of the true variance. The imaged underestimation of true ulnar variance should be taken into account when performing surgical procedures that alter the relative lengths of the radius and ulna.