Long-term results of distal oblique bundle reinforcement for treatment of chronic bidirectional instability of the distal radioulnar joint

Distal oblique bundle (DOB) reinforcement for treatment of post-traumatic bidirectional instability of the distal radioulnar joint (DRUJ) has previously been reported. The objective of the current study was to assess the incidence of symptomatic graft failure and the need for secondary wrist procedures at a longer follow-up in an updated patient cohort of 27 patients with 28 DOB reinforcement procedures. Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and patient-rated wrist/hand evaluation (PRWHE) outcome measures were also evaluated. At median 82 months follow-up, pre- to postoperative QuickDASH score improved from a mean of 62 (SD 14) to 31 (SD 22) (p < 0.01) and PRWHE score from a mean of 67 (SD 17) to 34 (SD 23) (p < 0.01). Symptomatic graft failure with resultant painful DRUJ instability occurred in four out of 28 procedures, which was better than the published results of alternative surgical options for DRUJ instability. DOB reinforcement presents a relatively safe, effective and durable method for treatment of post-traumatic DRUJ instability.Level of evidence: III

Long-term results of distal oblique bundle reinforcement for treatment of chronic bidirectional instability of the distal radioulnar joint

Distal oblique bundle (DOB) reinforcement for treatment of post-traumatic bidirectional instability of the distal radioulnar joint (DRUJ) has previously been reported. The objective of the current study was to assess the incidence of symptomatic graft failure and the need for secondary wrist procedures at a longer follow-up in an updated patient cohort of 27 patients with 28 DOB reinforcement procedures. Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and patient-rated wrist/hand evaluation (PRWHE) outcome measures were also evaluated. At median 82 months follow-up, pre- to postoperative QuickDASH score improved from a mean of 62 (SD 14) to 31 (SD 22) (p < 0.01) and PRWHE score from a mean of 67 (SD 17) to 34 (SD 23) (p < 0.01). Symptomatic graft failure with resultant painful DRUJ instability occurred in four out of 28 procedures, which was better than the published results of alternative surgical options for DRUJ instability. DOB reinforcement presents a relatively safe, effective and durable method for treatment of post-traumatic DRUJ instability.Level of evidence: III

Multiplanar reformation computed tomography for carpal malalignment

Correct interpretation of scaphoid axial length and carpal malalignment is difficult owing to the complex geometry of the scaphoid. Traditional measurements, such as the scapholunate angle and radiolunate angle, have shown limited reproducibility. To improve the assessment of these measurements, we used multiplanar reformation computed tomography with added average intensity projection. Four measurements for scaphoid morphology and carpal alignment were independently measured by four observers on computed tomography scans of 39 consecutive patients who were treated conservatively for scaphoid fracture. Fleiss's kappa for categorical results showed substantial agreement for the measurements of the scapholunate and radiolunate angles. Intraclass correlation coefficients were significant for measurements of the axial length, scapholunate angle and radiolunate angle. Our results suggest that multiplanar reformation computed tomography with added average intensity projection is a reliable technique for assessment of scaphoid morphology and carpal alignment

Association between bone shape and the presence of a fracture in patients with a clinically suspected scaphoid fracture

Scaphoid fractures are difficult to diagnose with current imaging modalities. It is unknown whether the shape of the scaphoid bone, assessed by statistical shape modeling, can be used to differentiate between fractured and non-fractured bones. Therefore, the aim of this study was to investigate whether the presence of a scaphoid fracture is associated with shape modes of a statistical shape model (SSM). Forty-one high-resolution peripheral quantitative computed tomography (HR-pQCT) scans were available from patients with a clinically suspected scaphoid fracture of whom 15 patients had a scaphoid fracture. The scans showed no motion artefacts affecting bone shape. The scaphoid bones were semi-automatically contoured, and the contours were converted to triangular meshes. The meshes were registered, followed by principal component analysis to determine mean shape and shape modes describing shape variance. The first five out of the forty shape modes cumulatively explained 87.8% of the shape variance. Logistic regression analysis was used to study the association between shape modes and fracture presence. The regression models were used to classify the 41 scaphoid bones as fractured or non-fractured using a cut-off value that maximized the sum of sensitivity and specificity. The classification of the models was compared with fracture diagnosis on HR-pQCT. A regression model with four shape modes had an area under the ROC-curve of 72.3% and correctly classified 75.6% of the scaphoid bones (fractured: 60.0%, non-fractured: 84.6%). To conclude, fracture presence in patients with a clinically suspected scaphoid fracture appears to be associated with the shape of the scaphoid bone