Clinical, radiological and patient-rated outcome comparison between total and partial ulnar head implants

This study aimed to analyse the clinical and radiological outcomes after ulnar head replacement and to compare partial and total ulnar head implants. Twenty-two patients with 23 implants were available with a mean follow-up time of 7 years (range 1.3 to 17) after distal radioulnar joint arthroplasty. At the final follow-up, patients had a low level of pain at rest and during effort, a median Disabilities of the Arm, Shoulder, and Hand (DASH) score of 12 and Patient-Rated Wrist Evaluation score of 12 with partial ulnar head implants, and scores of 20 and 22 in total ulnar head implants, respectively. While the range of motion in patients with partial ulnar head implants was slightly reduced in comparison with the preoperative condition and to the patients with total ulnar head implants, there was a tendency to a higher grip strength and rotational torque. Both types of prosthesis showed sigmoid notch resorptions and resorptions around the neck. We conclude that the results after partial ulnar head replacement do not significantly differ from the total ulnar head implants in many aspects. Level of evidence: III

157 Non-Surgical Management of an Acute Isolated Volar Dislocation of the Distal Radio-Ulnar Joint

Isolated distal radio-ulnar joint dislocations are rare and commonly missed on radiographs. A young male presented with severe pain and deformity of the left wrist, following a collision whilst playing rugby. This was easily diagnosed using plain radiographs, and the initial attempted reduction methods in the Emergency Department failed. The patient was subsequently anaesthetised in theatre, yet reduction by an accepted method of palmar to dorsal pressure over the interosseous membrane with simultaneous distraction of the wrist failed. A further attempt to manipulate the dislocated ulnar head was successful, with the same force applied whilst the wrist was maximally flexed and pronated – thereby avoiding an open reduction. The patient was asymptomatic at final follow-up, over one year later. This technique has not previously been described in the literature and may be used in similar injuries in the future.

Application of force-monitor ultrasonography to assess distal radioulnar joint instability in patients with triangular fibrocartilage complex injury

Introduction In this study, we evaluated the differences and measurement accuracy in the force–displacement relationship of the distal radioulnar joint (DRUJ) between patients with triangular fibrocartilage complex (TFCC) injury and healthy controls using force-monitor ultrasonography. Methods This study included 11 TFCC injury patients and 22 healthy controls. We evaluated differences in the force–displacement relationship of the DRUJ in these patients using force-monitor ultrasonography. Cyclic compression was applied to the dorsal surface of the ulnar head. Distance between the dorsal surface of the distal radius and ulnar head at the DRUJ level was measured in the initial and pressed-down positions. Changes in radioulnar displacement, applied force, and displacement-to-force ratio were measured. Furthermore, we compared the parameters between the affected and unaffected wrists and between TFCC injury patients and controls. Results The radioulnar displacement and displacement-to-force ratio were significantly larger in the affected wrists than in the unaffected wrists ( P = 0.003 and P = 0.02). The affected/unaffected side ratio of radioulnar displacement and displacement-to-force ratio were significantly larger in the TFCC injury patients than in the controls ( P = 0.003 and P = 0.02). The area under the curve was 0.82 for the affected/unaffected ratio of the radioulnar displacement. The optimal cutoff value indicated by the receiver-operating characteristic curve for the affected/unaffected ratio of the radioulnar displacement was 1.71; the sensitivity and specificity were 82% and 86%, respectively. Conclusions Assessing the DRUJ instability with force-monitor ultrasonography may help identify TFCC-injured wrists.

Arthroscopic Anatomy of the TFCC with Relevance to Function and Pathology

Introduction The authors present a new comprehensive arthroscopic anatomical description of the fibrocartilage complex “TFCC” which is related to the current TFCC functional and pathological knowledge. Methods Our description of the TFCC is based on an arthroscopic view from the 3-4 portal as observed in more than 100 wrist arthroscopies in fresh cadavers and more than 1000 diagnostic and/or therapeutic wrist arthroscopies. Results TFCC is considered as a 3-D-3-part box-like structure (Reins, Wall and Disc). The first TFCC component (“R”) corresponds to 2 strong radio-ulnar ligamentous Reins, one dorsal (DRUL) and one palmar (PRUL). This “V-shaped” RUL reins diverge from the fovea and ulnar styloid to the volar and dorsal edges of the sigmoid notch. It is a main stabilizer of the DRUJ. The second TFCC component (“W”) is a continuous, radially concave Peripheral Capsular Wall attached and perpendicular to the RUL reins. It surrounds the ulnar aspect of the ulno-carpal interval while attaching to the RUL reins proximally and to the medial carpus distally. Along with the radiocarpal ligaments, the TFCC peripheral capsular wall contributes to the stability of the carpus with respect to the radius-ulna entity. This is especially true for the thick volar TFCC capsular wall. The third TFCC component (“D”) is the disc proper which is a static and dynamic shock absorber intercalated between the ulnar head and the medial proximal row in the coronal/sagittal planes and between the two strands of the RUL in the axial plane. Its pathology is influenced and related to the ulnar variance. Discussion This new arthroscopic description of the TFCC provides a comprehensive anatomical, functional ant pathological background for TFCC disorders analysis and treatment. Currently known disorders are included as “R 1,2,3,4”, “W 1, 2, 3, 4”, and “D 1, 2”. Combined TFCC disorders and further new pathology descriptions may be included in this open classification.

A new quantitative evaluation system for distal radioulnar joint instability using a three-dimensional electromagnetic sensor

Background The accurate assessment of distal radioulnar joint (DRUJ) instability is still challenging as there is no established objective evaluation method. This study aimed to develop a noninvasive measurement method using a three-dimensional electromagnetic sensor system (EMS) to quantitatively assess and characterize the normal DRUJ movement in healthy volunteers. Methods The DRUJ movement was mimicked using both a block model and saw bone. Movement of the models was measured by EMS, and the accuracy and reproducibility of the measurements were assessed. In vivo measurement was performed in a sitting position with the elbow flexed and the forearm pronated. One sensor each was attached to the distal radial shaft and the ulnar head. The examiners fixed the distal radius and the carpal bones, moved the ulnar head from the dorsal to the volar side and measured the dorsovolar translation. The volar translation was measured by EMS and ultrasonography, and the correlation coefficient was calculated. The dorsovolar translation was evaluated in 14 healthy volunteers (7 men and 7 women) by three hand surgeons. The intraclass and inter-rater correlation coefficients (ICCs), the differences between the dominant and non-dominant sides and between men and women were assessed. Results The accuracy and reproducibility assessment results of the EMS showed high accuracy and reproducibility. In the comparison between EMS and ultrasonography, the correlation coefficient was 0.920 (p = 0.16 × 10-3). The ICC (1,5) for the intra-rater reliability was 0.856, and the ICC (2,5) for inter-rater reliability was 0.868. The mean ulnar head translation and difference between dominant and non-dominant sides were 6.00 ± 1.16 mm (mean ± SD) and − 0.12 ± 0.40 mm, respectively. There were no significant differences between any of the parameters. Conclusions A new measurement method using EMS could evaluate DRUJ movement with high accuracy, reproducibility, and intra- and inter-rater reliability. In healthy volunteers, the dorsovolar ulnar head translation was 6.00 mm. The difference between the dominant and non-dominant sides was < 1.0 mm with no significant difference. EMS provided an objective, non-invasive, real-time assessment of dynamic changes in the DRUJ. These findings could be useful in the treatment of patients with DRUJ instability.

VAUGHAN JACKSON SYNDROME DUE TO DISTAL RADIOULNAR JOINT OSTEOARTHRITIS: A CASE REPORT

Spontaneous extensor tendons rupture (Vaughan Jackson syndrome) is a common complication of rheumatoid arthritis, but it is also reported sporadically with non-rheumatoid osteoarthritis of the distal radioulnar joint (DRUJ). We described a case of 45 years old female who lost her ability to extend the little, ring and middle fingers sequentially after months of wrist pain and limitation of movement due to osteoarthritis of DRUJ. The condition was treated surgically by tendon transfer and ulnar head excision. The patient did well after surgery.

Radial Club Hand Treated by Paley Ulnarization Generation 3: Is this the New Centralization?

(1) Background: Patients treated with the two previous generations of ulnarization developed a bump related to the ulnar head becoming prominent on the radial side of the hand. To finally remedy this problem, a third generation of ulnarization was developed to keep the ulnar head contained. While still ulnar to the wrist center, the center of the wrist remains ulnar to the ulnar head, with the ulnar head articulating directly with the trapezoid and when present the trapezium. (2) Methods: Between 2019 and 2021, 22 radial club hands in 17 patients were surgically corrected with this modified version of ulnarization. (3) Results: In all 17 patients, the mean HFA (hand–forearm-angle) correction was 68.5° (range 12.2°–88.7°). The mean ulna growth was 1.3 cm per year (range 0.2–2 cm). There were no recurrent radial deviation deformities more than 15° of the HFA. (4) Conclusions: This new version of ulnarization may solve the problem of the ulna growing past the carpus creating a prominent ulnar bump. The results presented are preliminary but promising. Longer-term follow-up is needed to fully evaluate this procedure.