Chronic Posttraumatic Instability of the Distal Radioulnar Joint: Foveal Reattachment of the Triangular Fibrocartilage Complex With Dorsal Capsuloplasty and Extensor Retinaculum Imbrications

Ligament reconstruction for distal radioulnar joint instability with the biomechanical analysis: A case report

RATIONALE

The aim of the study is to evaluate the clinical effects and feasibility on chronic distal radioulnar unstable joint (DRUJ) under wrist arthroscope triangular fibrocartilage complex (TFCC) repair and reconstruction. The biomechanical characteristics of the recovery process after treatment were analyzed using finite element modeling.

PATIENT CONCERNS

A patient with chronic DRUJ instability was treated with reconstruction of the distal radioulnar ligament using the Adams Berger method. Piano sign and forearm rotation tests were used to evaluate the function of the DRUJ. Grip power, range of motion, and visual analog scale scores were recorded at the last follow-up. Joint function was evaluated by the disability of the arm, shoulder, and hand score. A geometric model for the surgical repair of TFCC damage, meshing in finite element simulation, and stress distribution of the repaired ligament during forearm rotation were analyzed by finite element simulation.

DIAGNOSES

The diagnosis was confirmed as chronic DRUJ instability.

INTERVENTIONS AND OUTCOMES

The patient had no postoperative complications and was followed-up for 6 months. Stability was achieved in all patients. The results of the stress and forearm rotation tests are negative. At the last follow-up, the grip power, disability of the arm, shoulder, and hand score, visual analog scale score, and range of motion of the wrist were significantly improved compared with the preoperative values (P < .05).

LESSONS

TFCC repair and reconstruction under wrist arthroscopy can effectively treat chronic DRUJ and improve wrist function. Our study established a three-dimensional finite element model of the entire DRUJ, which provided a digital visual platform for simulating the biomechanical features of the TFCC, DRUJ, and other structures in different states. This study demonstrated that the rotation angle of the wrist joint should be confined within 75° for a short period after surgery to avoid tearing the tendon as a result of excessive force. It also provides an intuitive simulation tool for the design of TFCC repair and the evaluation of curative effects.

Effect of dorsal capsular imbrication on intraoperative DRUJ instability following arthroscopic TFCC repair surgery

BACKGROUND

To assess the clinical outcomes and identify the ideal indication for implementing dorsal distal radioulnar joint (DRUJ) capsular imbrication after triangular fibrocartilage complex (TFCC) repair in cases of DRUJ instability.

METHODS

We conducted a retrospective study on patients who underwent arthroscopic TFCC repair between 2016 and 2021. Inclusion criteria comprised a symptomatic ulna fovea sign for over 6 months and dorsal DRUJ subluxation on magnetic resonance imaging. A total of 225 patients were divided into two groups: Group 1 (135 cases) with a negative ballottement test after "Cross-form TFCC repair" (CR) and Group 2 (90 cases) with a positive ballottement test after "Cross-form TFCC repair" and augmented DRUJ stability through dorsal DRUJ capsular imbrication (CR + DCI). Pain visual analog scale score (VAS), grip strength, modified Mayo Wrist Score (MMWS), wrist range of motion (ROM), and patient-reported outcomes (PROMs) were assessed for a minimum of 3 years postoperatively.

RESULTS

Both groups showed significant improvements in pain VAS score, grip strength, wrist ROM, MMWS, and PROMs between the preoperative and postoperative periods (all P < 0.05). Recurrent DRUJ instability occurred in 3.7% and 1.1% of patients in the "CR" and "CR + DCI" groups, respectively, with a significant difference. Despite the "CR + DCI" group initially exhibiting inferior ROM compared with the "CR" group, subsequently, no significant difference was noted between them.

CONCLUSIONS

Dorsal DRUJ capsular imbrication effectively reduces postoperative DRUJ instability rates, enhances grip strength, and maintains wrist ROM in patients with a positive intra-operative ballottement test after arthroscopic TFCC repair.

Distal Radioulnar Joint Instability: Diagnosis and Treatment

Distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) tears are more usual than estimated and are frequently overlooked. Diagnosis is often clinical, which can be confirmed using computed tomography (CT) scan and magnetic resonance imaging (MRI). In doubtful cases, bilateral computed tomography in neutral forearm rotation, supination, and pronation should also be performed. Wrist arthroscopy can be diagnostic and therapeutic for ulnar-sided wrist pain. Two systematic reviews showed equivalent outcomes between open and arthroscopic repair of the TFCC. There is scant proof to advise one technique over the other in clinical practice. TFCC repair and reconstruction are contraindicated when there is a bony deformation of the radius or ulna or osteoarthritis of the DRUJ. With the advancement of implant arthroplasty, salvage procedures are less desirable. Constrained distal radioulnar arthroplasty is stable, and the longevity is encouraging.