Reconstruction Of Distal Radioulnar Ligaments Research Articles

Biomechanical evaluation of interference screw fixation techniques for distal radioulnar ligament reconstruction: a cadaveric experimental study.

In the reconstruction of distal radioulnar ligaments (DRULs), interference screws can be used for antegrade or retrograde fixation of grafts to the ulna. However, the biomechanics of interference screw fixation are currently unknown. This study aimed to determine the biomechanical effects of these two fixations on the distal radioulnar joint (DRUJ) in a cadaveric model and to investigate the appropriate initial tension. A total of 30 human cadaver upper extremities were used, and the DRULs were reconstructed according to Adams' procedure. First, eight specimens were randomly divided into two groups: antegrade and retrograde, followed by translational testing and load testing. Then, the other eight specimens were divided into the two groups above, and the contact mechanics, including forces, areas, and pressures, were measured. Finally, to investigate the appropriate initial tension, the remaining 14 specimens were fixed with interference screws under different tensions in an antegrade way, and the translational testing was repeated as before. In the neutral position, antegrade fixation exhibited less translation than retrograde fixation (7.21 ± 0.17mm versus 10.77 ± 1.68mm, respectively). The maximum failure load was 70.45 ± 6.20N in antegrade fixation, while that in retrograde fixation was 35.17 ± 2.95N (P < 0.0001). Antegrade fixation exhibited a larger increase in contact force than retrograde fixation (99.72% ± 23.88% versus 28.18% ± 10.43%) (P = 0.001). The relationship between tension and displacement was nonlinear (Y = - 1.877ln(x) + 7.94, R2 = 0.868, P < 0.0001). Compared with retrograde fixation, the antegrade fixation of interference screws may be a more reliable surgical technique, as it shows a higher failure load and stability. In addition, to avoid the risk of potential arthritis caused by anterograde fixation, we propose an equation to determine the appropriate initial tension in DRUL reconstruction.

Palmaris longus tendon for distal radio-ulnar ligament reconstruction – A novel technique

Palmaris longus tendon for distal radio-ulnar ligament reconstruction – A novel technique

A Biomechanical Evaluation of the DRUJ After Distal Oblique Bundle Reconstruction

Distal oblique bundle (DOB) reconstruction for distal radioulnar joint (DRUJ) instability is an alternative to the Adams 2-incision distal radioulnar ligament reconstruction. The DOB reconstruction offers a single incision and is a technically less demanding procedure requiring a shorter tendon autograft. The DOB and Adams reconstruction may provide similar stability. This study sought to compare the biomechanical stability of the 2 DRUJ reconstructions. We hypothesized that DOB reconstruction would result in equivalent DRUJ translation, cyclic loading to failure, and maximal load to failure compared with the Adams reconstruction. Ten fresh-frozen cadaver arms underwent DOB or Adams reconstructions. Volar, dorsal, and total translation of the radius relative to the ulna at the DRUJ were measured before and after each reconstruction. Translation was measured with a 20-N force in neutral position and 60° in pronation and supination. Measurements were obtained using a custom jig and electromagnetic motion-tracking system sensors. Total cycles and maximal load to failure of each reconstruction were measured and recorded using an electromechanical testing machine. There was a DOB incidence of 70%. Distal radioulnar joint translation, total cycles, and failure load were similar for the 2 reconstructions. On average, the DOB reconstruction had less dorsal translation than did the Adams in supination. Translation in the DOB reconstruction was similar to that of native DRUJs. In supination, on average, the Adams reconstruction had greater total, volar, and dorsal translation compared with native DRUJs. In terms of translation, cyclical loading, and maximal load to failure, the DOB reconstruction for DRUJ instability is similar to the Adams reconstruction. This pilot study supports the DOB reconstruction as a possible alternative to the Adams reconstruction for DRUJ instability. The DOB reconstruction may theoretically reduce patient morbidity because it requires only one incision and a shorter tendon graft. However, further clinical and cadaveric studies are required to determine biomechanical equivalence and impact on patient morbidity.

Classification of ulnar triangular fibrocartilage complex tears. A treatment algorithm for Palmer type IB tears.

II.

Stabilization of the Distal Radioulnar Joint According to Adams: Clinical, and Radiological Results

Stabilization of the distal radioulnar joint (DRUJ) with reconstruction of distal radioulnar ligaments as outlined by Adams is indicated if a refixation of the triangular fibrocartilage complex (TFCC) is no longer possible. There is little information given on the results of these procedures in literature. The purpose of this retrospective study was to analyze with use of objective and subjective criteria, whether the reconstruction of the radioulnar ligaments according to Adams allows a sufficient re-stabilization of the DRUJ. 14 patients (9 female, 5 male) with a mean age of 29 (24-62) years underwent an Adams' procedure between 2004 to 2011. After an average follow up of 67 (26-110) months 11 patients could be examined retrospectively regarding functional results and subjective self assessment. As objective parameters assessment of distal radioulnar joint stability, range of forearm rotation and grip strength were measured. Krimmer- and Mayo Wrist Score were evaluated. Subjective parameters as DASH-score, patient's self assessment and pain (verbal and visual analogue scale) were recorded. In 5 patients the DRUJ was stable, in 2 it was lax. According the 4 patients with ongoing instability, one patient reported on improvement, 2 on unchanged instability and one an impaired sensation of instability. In 2 patients clicking during forearm rotation could be provoked. 2 patients suffered from restricted forearm rotation with loss of range of motion of 60 and 70° respectively. Pronation-supination averaged 89% of the opposite side and 99% compared to preoperative. Grip strength averaged 69% of the opposite side. Krimmer-Score was 74, Mayo Wrist-Score 73, and DASH-Score 24 points. Pain at rest on visual analogue scale (0-10) was 3 and 5 with activity. 6 patients had improved, 2 declined and 3 unchanged pain. Patient´s satisfaction rated 0-10 was 8. Eight would undergo again same operation procedure. The clinical findings show, that reconstruction of distal radioulnar ligaments according to Adams in patients with DRUJ instability and no repairable parts of TFCC, do not allow to re-stabilize the DRUJ in all patients. There is a need for further investigations trying to re-stabilize the DRUJ.

All-Arthroscopic Knotless Suture Anchor Repair of Triangular Fibrocartilage Complex Fovea Tear by the 2-Portal Technique

After the importance of the deep fiber of the distal radioulnar ligament had been acknowledged, some repair techniques have been introduced. Because the knotless suture anchor does not cause any knot irritation and yields appropriate tension, it is a useful fixation material. All-arthroscopic knotless suture anchor repair of the triangular fibrocartilage complex fovea tear by a 2-portal technique is easier and less vulnerable to ulnar nerve injury than the original Geissler technique. Instead of the suture hook and accessory portal, this technique uses the always-sharp 18-gauge needle and percutaneous route. This change results in the repair of the complex fovea tear having the smallest possible remnant tissue. Repair of triangular fibrocartilage complex fovea tears combined type IB, ID, and IIC tears can reduce the chance of needing to perform distal radioulnar ligament reconstruction.

Selection of Tendon Grafts for Distal Radioulnar Ligament Reconstruction and Report of a Modified Technique

To investigate the graft length necessary to complete a distal radioulnar ligament reconstruction and assess the suitability of several tendon graft sources. We measured the graft length needed to complete the distal radioulnar ligament reconstruction in 7 fresh-frozen cadaver specimens. The pure tendon lengths of 7 tendon graft sources were measured: palmaris longus, extensor indicis proprius, slips of extensor digiti minimi and abductor pollicis longus, and portions of flexor carpi ulnaris, flexor carpi radialis, and extensor carpi ulnaris. A modified technique that allows for a shorter length of graft is also described, and the suitability of each graft source for this technique was assessed. The mean graft lengths needed to complete the original and modified reconstructions were 138 mm and 89 mm, respectively. The average length of the tendon graft when measured as pure tendon was: palmaris longus (127 mm), slip of extensor digiti minimi (112mm), extensor indicis proprius (100 mm), partial flexor carpi radialis (87 mm), slip of abductor pollicis longus (69 mm), partial flexor carpi ulnaris (67 mm), and partial extensor carpi ulnaris (67 mm). The palmaris longus was too short for the original technique in the majority of specimens but was sufficient to complete the modified technique in every specimen that had a palmaris longus. Six specimens also had an extensor indicis proprius of suitable length for the modified technique. The length of donor graft required for the modified reconstruction was significantly less than that needed for the original reconstruction. Three specimens had no donor tendons sufficiently long to complete the original technique if a pure tendon graft were used, whereas the modified technique could be completed in all specimens. Many tendon graft sources in the upper extremity are of insufficient length to complete the distal radioulnar ligament reconstruction as described. A modified technique using suture anchors may be a useful alternative in such cases.

Anatomic Reconstruction of the Distal Radioulnar Ligament for Posttraumatic Distal Radioulnar Joint Instability

BackgroundTo analyze clinical outcomes after anatomical reconstruction of distal radioulnar ligaments in patients with chronic post-traumatic instability of the distal radioulnar joint.MethodsAnatomical reconstruction was performed in 16 patients with subluxation or dynamic instability of distal radioulnar joint following trauma. Osteotomy was performed simultaneously in 10 patients with radial malunion. The average follow-up period was 18.9 months. For clinical outcome assessment, we performed the anteroposterior stress test, measured the range of motion and grip strength, and performed radiological examination. For assessment of the pain and function, we used the Patient Rated Wrist Evaluation, the Disabilities of the Arm, Shoulder and Hand, and the Modified Mayo Wrist Score.ResultsAnteroposterior stress test performed at the last follow-up showed normal in 12 patients, mild laxity in 3, and residual subluxation in one. The average Patient Rated Wrist Evaluation was 9.1 for pain and 11.2 for function. The average Disabilities of the Arm, Shoulder and Hand score was 10.5. The average Modified Mayo Wrist Score was 92.8; there were 10 excellent, 5 good, and 1 poor case. The average grip strength improved from 69.7 1b to 80.9 1b. A revision osteotomy was performed on the patient with residual subluxation in order to obtain normal alignment of the joint.ConclusionsAnatomical reconstruction of the distal radioulnar ligaments is recommended to restore distal radioulnar joint stability. In addition to ligament reconstruction, realignment of the distal radioulnar joint seems critical when the instability is combined with malunion of the radius.

DISTAL RADIOULNAR JOINT INSTABILITY

The distal radioulnar joint is inherently unstable. Pathologic instability can be acute or chronic; it can be dorsal, palmar, or multidirectional; and it can result primarily from soft-tissue injury or osseous malunion. Recognition of the type and cause of instability is fundamental in order to provide effective treatment. The distal radioulnar joint is a distal articulation in the biarticulate rotational arrangement of the forearm. This articulation allows only one degree of motion: pronation and supination. The sigmoid notch of the radius is concave and is shallow with a radius of curvature of 15 mm. The ulnar head is semicylindrical and has an articulate convexity of 220° with a radius of curvature of 10 mm1. The ulnar head is surrounded by an ulnar carpal ligament complex. This consists of the ulnolunate and ulnotriquetral ligaments, which originate from the palmar radioulnar ligament near the ulnar styloid process. When seen through an arthroscope, these ligaments appear to be continuous with the triangular fibrocartilage. The triangular fibrocartilage is a fibrocartilaginous disk originating at the junction of the lunate fossa and the sigmoid notch and inserting at the base of the ulnar styloid. Its central portion is cartilaginous, and it is designed for weight-bearing. It is also avascular. The peripheral margins are composed of thick lamellar cartilage designed for tensile loading and are called the dorsal and palmar radioulnar ligaments . The peripheral margins of the triangular fibrocartilage are well vascularized from the palmar and dorsal branches of the anterior interosseous artery and from the ulnar artery. The ulnar styloid is the continuation of the subcutaneous ridge of the ulnar shaft, and it stands as a strut on the end of the ulna to stabilize the ulnar soft tissues of the wrist. The sheath of the extensor carpi ulnaris, the ulnocarpal ligaments, and …

Reconstruction of the posttraumatic unstable distal radioulnar joint

Although not a common problem, the posttraumatic unstable distal radioulnar joint can be difficult to treat. This article focuses on the various methods for reconstruction of the unstable distal radioulnar joint. Attention focuses specifically on anatomic reconstruction of distal radioulnar ligaments. The authors' technique is presented in detail.