The evolution of radiological measurements and the association with clinician and patient reported outcome following distal radius fractures in non-osteoporotic patients: what is clinically relevant?

Introduction: Following distal radius fractures in young non-osteoporotic patients, clinical relevancy of outcome has been scarcely reported. Outcome can be put in perspective by using measurement errors of radiological measurements and Minimal Important Change when reporting on clinician and patient reported outcome. Aim of this study was to assess the clinical relevance of radiological measurements, clinician and patient reported outcomes following distal radius fractures in young non-osteoporotic patients.Methods: Retrospective cohort study. Non-osteoporotic patients following a distal radius fracture were selected. Radiographs of both wrists were obtained at baseline, 6 weeks and at follow-up. Active range of motion and grip strength measurements were obtained at the follow-up visit and 4 questionnaires were answered to assess pain, upper extremity functioning, and health status.Results: Seventy-three patients (32 women, 41 men) with a mean age of 33.5 (SD 9.2) years at the time of injury were included. Median follow up was 62 months (IQR 53.0-84.5). Several radiological measurements evolved statistically significantly over time, however none exceeded measurement errors. Flexion/extension difference of injured compared to uninjured wrist (mean difference 11.2°, t = -7.5, df = 72, p < 0.001), exceeded Minimal Important Change, while grip strength differences did not. When comparing patients with DRFs to healthy controls, only the differences on Patient Reported Wrist Evaluation subscales "pain", "function" and total scores exceeded minimal important change (8, 10 and 13 points, respectively). Multivariable regression analysis revealed statistically significant relationships between residual step-off and respectively diminished flexion/extension (B = -36.8, 95% CI -62; -11.1, p  =  0.006), diminished radial/ulnar deviation (B = -17.9, 95% CI -32.0; -3.9, p  =  0.013) and worse ShortForm-36 "mental component score" (B = -15.4, 95% CI -26.6; -4.2, p < 0.001).Conclusion: Radiological measurements following distal radius fractures seem to evolve over time, but differences were small and were probably not clinically relevant. Range of motion, in particular flexion/extension, was impaired to such extend that it was noticeable for a patient, whereas grip strength was not impaired. The Patient Reported Wrist Evaluation was clinically relevantly diminished. Residual articular incongruency seems to influence range of motion.Implications for rehabilitationReporting Minimal Important Change regarding clinician and patient reported outcome following distal radius fractures is of more clinical value than reporting on statistical significance.Following distal radius fractures, the changes in radiological measurements do not seem to reflect a clinical relevant change.Range of motion, in particular flexion/extension, should be measured following distal radius fractures, as this might be impaired in a clinically relevant way.Measuring grip strength is of less importance following distal radius fractures, because grip strength does not seem to be affected.Residual articular incongruency seems to influence range of motion and therefore should be reduced to a minimum when treating non-osteoporotic patients.

Unenhanced CT imaging is highly sensitive to exclude pheochromocytoma: a multicenter study

BACKGROUND

A substantial proportion of all pheochromocytomas is currently detected during the evaluation of an adrenal incidentaloma. Recently, it has been suggested that biochemical testing to rule out pheochromocytoma is unnecessary in case of an adrenal incidentaloma with an unenhanced attenuation value ≤10 Hounsfield Units (HU) at computed tomography (CT).

OBJECTIVES

We aimed to determine the sensitivity of the 10 HU threshold value to exclude a pheochromocytoma.

METHODS

Retrospective multicenter study with systematic reassessment of preoperative unenhanced CT scans performed in patients in whom a histopathologically proven pheochromocytoma had been diagnosed. Unenhanced attenuation values were determined independently by two experienced radiologists. Sensitivity of the 10 HU threshold was calculated, and interobserver consistency was assessed using the intraclass correlation coefficient (ICC).

RESULTS

214 patients were identified harboring a total number of 222 pheochromocytomas. Maximum tumor diameter was 51 (39-74) mm. The mean attenuation value within the region of interest was 36 ± 10 HU. Only one pheochromocytoma demonstrated an attenuation value ≤10 HU, resulting in a sensitivity of 99.6% (95% CI: 97.5-99.9). ICC was 0.81 (95% CI: 0.75-0.86) with a standard error of measurement of 7.3 HU between observers.

CONCLUSION

The likelihood of a pheochromocytoma with an unenhanced attenuation value ≤10 HU on CT is very low. The interobserver consistency in attenuation measurement is excellent. Our study supports the recommendation that in patients with an adrenal incidentaloma biochemical testing for ruling out pheochromocytoma is only indicated in adrenal tumors with an unenhanced attenuation value >10 HU.