Computer-assisted correction of incongruent distal radioulnar joints in patients with symptomatic ulnar-minus variance

[Treatment of Congenital Ulnar Impingement Syndrome by Corrective Osteotomy of the Distal Radius - Clinical Results]

BACKGROUND

In 2016, a new method was described to treat the painful impingement syndrome of the DRUJ: decompression corrective osteotomy of the distal radius. Clinical symptoms are based on a positive compression test; pain occurs with weight-bearing on the forearm. This phenomenon is seen in conjunction with a deformed sigmoid notch together with ulna minus-variance, which leads to increased tension in the distal oblique bundle of the interosseous membrane. The etiology of the condition can be either congenital, post-traumatic, or iatrogenic. Through the proposed osteotomy, decompression in the DRUJ is achieved. This study summarises the results of these surgical procedures performed in our hand centre exclusively in cases of congenital origin.

PATIENTS UND METHODS

Remodelling of the DRUJ is achieved through the shortening of the distal radius together with closed wedge osteotomy. Relief of the interosseous membrane is accomplished by ulnar translation of the radial shaft. This study only included patients with congenital incongruency in the DRUJ. The results were evaluated using a visual analogue scale (VAS) and the Krimmer Wrist Score and by measuring the preoperative and postoperative range of motion as well as grip strength.

RESULTS

Within 11 years, 45 procedures were performed with our method on 38 patients, of which 17 were treated on the right side, 14 on the left side, and 7 bilaterally. In cases of bilateral incongruency, only the symptomatic side was treated. The statistical evaluation showed a significant reduction of pain on the VAS from 7.2 to 2 (p<0.001). No significant changes were seen in the range of motion (p=0.812). The Krimmer Wrist Score showed good to excellent results in almost 90% of cases.

CONCLUSION

If the indication criteria are met, contraindications are avoided and the osteotomy is correctly performed, this technique leads to an improvement of patients' functionality and quality of life. From a preventive viewpoint, the influence on the progression of the degenerative changes is yet to be demonstrated in further studies. At any rate, this is a safe procedure, which leaves the path open for other possible options.

3D-assisted corrective osteotomies of the distal radius: a comparison of pre-contoured conventional implants versus patient-specific implants

PURPOSE

There is a debate whether corrective osteotomies of the distal radius should be performed using a 3D work-up with pre-contoured conventional implants (i.e., of-the-shelf) or patient-specific implants (i.e., custom-made). This study aims to assess the postoperative accuracy of 3D-assisted correction osteotomy of the distal radius using either implant.

METHODS

Twenty corrective osteotomies of the distal radius were planned using 3D technologies and performed on Thiel embalmed human cadavers. Our workflow consisted of virtual surgical planning and 3D printed guides for osteotomy and repositioning. Subsequently, left radii were fixated with patient-specific implants, and right radii were fixated with pre-contoured conventional implants. The accuracy of the corrections was assessed through measurement of rotation, dorsal and radial angulation and translations with postoperative CT scans in comparison to their preoperative virtual plan.

RESULTS

Twenty corrective osteotomies were executed according to their plan. The median differences between the preoperative plan and postoperative results were 2.6° (IQR: 1.6-3.9°) for rotation, 1.4° (IQR: 0.6-2.9°) for dorsal angulation, 4.7° (IQR: 2.9-5.7°) for radial angulation, and 2.4 mm (IQR: 1.3-2.9 mm) for translation of the distal radius, thus sufficient for application in clinical practice. There was no significant difference in accuracy of correction when comparing pre-contoured conventional implants with patient-specific implants.

CONCLUSION

3D-assisted corrective osteotomy of the distal radius with either pre-contoured conventional implants or patient-specific implants results in accurate corrections. The choice of implant type should not solely depend on accuracy of the correction, but also be based on other considerations like the availability of resources and the preoperative assessment of implant fitting.