Interdisciplinary consensus statements on imaging of DRUJ instability and TFCC injuries

OBJECTIVES

The purpose of this agreement was to establish evidence-based consensus statements on imaging of distal radioulnar joint (DRUJ) instability and triangular fibrocartilage complex (TFCC) injuries by an expert group using the Delphi technique.

METHODS

Nineteen hand surgeons developed a preliminary list of questions on DRUJ instability and TFCC injuries. Radiologists created statements based on the literature and the authors' clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panelists consisted of twenty-seven musculoskeletal radiologists. The panelists scored their degree of agreement to each statement on an 11-item numeric scale. Scores of "0," "5," and "10" reflected complete disagreement, indeterminate agreement, and complete agreement, respectively. Group consensus was defined as a score of "8" or higher for 80% or more of the panelists.

RESULTS

Three of fourteen statements achieved group consensus in the first Delphi round and ten statements achieved group consensus in the second Delphi round. The third and final Delphi round was limited to the one question that did not achieve group consensus in the previous rounds.

CONCLUSIONS

Delphi-based agreements suggest that CT with static axial slices in neutral rotation, pronation, and supination is the most useful and accurate imaging technique for the work-up of DRUJ instability. MRI is the most valuable technique in the diagnosis of TFCC lesions. The main indication for MR arthrography and CT arthrography are Palmer 1B foveal lesions of the TFCC.

CLINICAL RELEVANCE STATEMENT

MRI is the method of choice for assessing TFCC lesions, with higher accuracy for central than peripheral abnormalities. The main indication for MR arthrography is the evaluation of TFCC foveal insertion lesions and peripheral non-Palmer injuries.

KEY POINTS

• Conventional radiography should be the initial imaging technique in the assessment of DRUJ instability. CT with static axial slices in neutral rotation, pronation, and supination is the most accurate method for evaluating DRUJ instability. • MRI is the most useful technique in diagnosing soft-tissue injuries causing DRUJ instability, especially TFCC lesions. • The main indications for MR arthrography and CT arthrography are foveal lesions of the TFCC.

Interdisciplinary consensus statements on imaging of scapholunate joint instability

Objectives

The purpose of this agreement was to establish evidence-based consensus statements on imaging of scapholunate joint (SLJ) instability by an expert group using the Delphi technique.

Methods

Nineteen hand surgeons developed a preliminary list of questions on SLJ instability. Radiologists created statements based on the literature and the authors’ clinical experience. Questions and statements were revised during three iterative Delphi rounds. Delphi panellists consisted of twenty-seven musculoskeletal radiologists. The panellists scored their degree of agreement to each statement on an eleven-item numeric scale. Scores of ‘0’, ‘5’ and ‘10’ reflected complete disagreement, indeterminate agreement and complete agreement, respectively. Group consensus was defined as a score of ‘8’ or higher for 80% or more of the panellists.

Results

Ten of fifteen statements achieved group consensus in the second Delphi round. The remaining five statements achieved group consensus in the third Delphi round. It was agreed that dorsopalmar and lateral radiographs should be acquired as routine imaging work-up in patients with suspected SLJ instability. Radiographic stress views and dynamic fluoroscopy allow accurate diagnosis of dynamic SLJ instability. MR arthrography and CT arthrography are accurate for detecting scapholunate interosseous ligament tears and articular cartilage defects. Ultrasonography and MRI can delineate most extrinsic carpal ligaments, although validated scientific evidence on accurate differentiation between partially or completely torn or incompetent ligaments is not available.

Conclusions

Delphi-based agreements suggest that standardized radiographs, radiographic stress views, dynamic fluoroscopy, MR arthrography and CT arthrography are the most useful and accurate imaging techniques for the work-up of SLJ instability.

Key Points

• Dorsopalmar and lateral wrist radiographs remain the basic imaging modality for routine imaging work-up in patients with suspected scapholunate joint instability.

• Radiographic stress views and dynamic fluoroscopy of the wrist allow accurate diagnosis of dynamic scapholunate joint instability.

• Wrist MR arthrography and CT arthrography are accurate for determination of scapholunate interosseous ligament tears and cartilage defects.

Treatment of the scaphoid humpback deformity - is correction of the dorsal intercalated segment instability deformity critical?

Treatment of scaphoid fractures has been focused mainly on achieving union, with less attention to restoring normal scaphoid shape and orientation. Malalignment of one carpal bone will disrupt the kinetics of the entire wrist. The dorsal intercalated segment instability deformity associated with scaphoid waist nonunion is a nondissociative form of carpal instability. It has to be reduced in the treatment of scaphoid waist nonunions to avoid kinetic problems that will lead to arthritic changes. Computerized tomography scanning has become indispensable to visualize the humpback deformity clearly. Different techniques may be used to restore the normal anatomy of scaphoid, from non-vascularized graft to arthroscopic bone grafting, and also the option of vascularized bone grafting.

The Anatomy of the Dorsal Capsulo-Scapholunate Septum: A Cadaveric Study

Background  Tears of the dorsal radiocarpal capsule at the level of the scapholunate interosseous ligament (SLIL) have recently been described in association with predynamic scapholunate instability. Purpose  The aim of this anatomical study of the dorsal capsulo-scapholunate septum (DCSS) was to examine the connection of the dorsal capsule on the SLIL and dorsal intercarpal ligament (DICL). Methods  Fourteen fresh frozen wrists from seven adult cadavers were dissected through a dorsal approach. Any dorsal attachment of the DICL on the dorsal surface of the SLIL, that is, the DCSS, was identified and measured (height and width). Results  The DCSS was consistently found connecting the DICL, the dorsal radiocarpal capsule, and the dorsal aspect of the SLIL. It was formed by the confluence of three arches like intersecting ribs in gothic architecture. The mean dimensions of the DCSS were 5.8 mm in height and 4.0 mm in maximum width. Conclusion  The DCSS that connects the SLIL with the dorsal capsule and DICL could be a constant structure of dorsal wrist. Further investigation is required to study the histology of the DCSS and its biomechanical properties in isolation to know whether the DCSS can be considered a secondary stabilizer of the scapholunate ligament complex. Clinical Relevance  A better anatomical knowledge of scapholunate ligament complex could help understand and manage instability of the wrist.

Erratum: The PARC Lesion: A Posterior Avulsion of the Radiocarpal Capsule

[This corrects the article DOI: 10.1055/s-0036-1584162.].

Indications, techniques, and outcomes of arthroscopic repair of scapholunate ligament and triangular fibrocartilage complex

This review includes updated understanding of the roles of intrinsic and extrinsic carpal ligaments in scapholunate instability and details the author's experience of indications, arthroscopic repair methods, and outcomes of treating the instability. A classification on triangular fibrocartilage complex injuries is reviewed, followed by author's indications, methods, and outcomes of arthroscopic repair of triangular fibrocartilage complex injuries.

The PARC Lesion: A Proximal Avulsion of the Radiocarpal Capsule

Purpose A proximal avulsion of the radiocarpal capsule (PARC) is a cause of persisting posttraumatic wrist pain. This lesion is often overlooked and left untreated during wrist arthroscopy. Materials and Methods A record review was performed on 13 patients with this lesion who underwent diagnostic wrist arthroscopy after failed conservative treatment. We retrospectively reviewed the results of an arthroscopic repair method in 13 patients. Results In 11 of the 13 consecutive cases the lesion was sutured using an arthroscopic dorsal capsule-ligamentous repair technique. Postoperatively, all high-demand patients were able to return to their previous sports. Discussion The PARC lesion is usually overlooked during diagnostic arthroscopy since it may be covered by synovial or fibrous tissue. It often coexists with scapholunate ligament or triangular fibrocartilage complex injuries. This lesion is amenable to an arthroscopic repair with satisfactory clinical results.

Augmented reality-based navigation system for wrist arthroscopy: feasibility

PURPOSE

In video surgery, and more specifically in arthroscopy, one of the major problems is positioning the camera and instruments within the anatomic environment. The concept of computer-guided video surgery has already been used in ear, nose, and throat (ENT), gynecology, and even in hip arthroscopy. These systems, however, rely on optical or mechanical sensors, which turn out to be restricting and cumbersome. The aim of our study was to develop and evaluate the accuracy of a navigation system based on electromagnetic sensors in video surgery.

METHODS

We used an electromagnetic localization device (Aurora, Northern Digital Inc., Ontario, Canada) to track the movements in space of both the camera and the instruments. We have developed a dedicated application in the Python language, using the VTK library for the graphic display and the OpenCV library for camera calibration.

RESULTS

A prototype has been designed and evaluated for wrist arthroscopy. It allows display of the theoretical position of instruments onto the arthroscopic view with useful accuracy.

DISCUSSION

The augmented reality view represents valuable assistance when surgeons want to position the arthroscope or locate their instruments. It makes the maneuver more intuitive, increases comfort, saves time, and enhances concentration.

Anatomical Description of the Dorsal Capsulo-Scapholunate Septum (DCSS)-Arthroscopic Staging of Scapholunate Instability after DCSS Sectioning

Background The dorsal capsuloligamentous scapholunate septum (DCSS) is a confluence of the dorsal capsule, the dorsal intercarpal ligament (DIC), and the scapholunate interosseous ligament (SLIOL). It appears to play a role in the stability of the scapholunate articulation. The purpose of this study was to describe the anatomical basis for this structure and to investigate its role in scapholunate instability through sectioning of this structure followed by an arthroscopic and fluoroscopic analysis. Material and Methods In the anatomical part of the study we dissected 3 fresh cadaver wrists to examine the anatomy of the DCSS. In the arthroscopic part of the study we assessed the EWAS grade of SL instability before and after sectioning the DCSS and measured the scapholunate and radiolunate angles fluoroscopically. Results Sectioning the DCSS increased the EWAS grade of SL instability but did not affect the scapholunate gap, the scapholunate angle or radiolunate angle. Conclusion We have demonstrated that there is a distinct structure that is separate from the dorsal capsule, which we have labeled the Dorsal Capsuloligamentous Scapholunate Septum. We believe that the DCSS is a previously unreported secondary stabilizer of the SL joint which may have therapeutic and prognostic implications.

Arthroscopic dorsal capsulo-ligamentous repair in the treatment of chronic scapho-lunate ligament tears

Introduction Scapholunate ligament injuries usually result due to a fall on the outstretched hand leading to scapholunate instability. The natural history of untreated scapholunate instability remains controversial and usually results in late arthritic changes- the so-called "SLAC" wrist. The advent of wrist arthroscopy helps in early diagnosis and treatment of these serious injuries. In selected cases with reducible scapholunate instability (Garcia-Elias stages 2, 3 and 4) we propose a new "all arthroscopic dorsal capsulo- ligamentous repair" with the added advantage of early rehabilitation and prevention of post-operative stiffness. Material and Methods We report the results of our series of 57 consecutive patients suffering from chronic wrist pain refractory to conservative measures. All patients underwent a thorough clinical examination in addition to a standard set of radiographs and MRI exam; and they were treated by an all-arthroscopic dorsal capsulo-ligamentous repair under loco-regional anesthesia on an ambulatory basis. All patients were available for follow-up at regular intervals during the post-operative period. At follow-up, the wrist ROM in all directions, the grip strength, DASH questionnaire and pain relief based on the VAS were recorded for both- the operated and contra-lateral sides. Results There were 34 males & 23 females with a mean age of 38.72 ± 11.33 years (range 17-63 years). The dominant side was involved in 52 cases. The mean time since injury was 9.42 ± 6.33 months (range 3-24 months) and the mean follow-up was 30.74 ± 7.05 months (range 18-43 months). The mean range of motion improved in all directions. The mean difference between the post- and pre-operative extension was 14.03° (SEM = 1.27°; p < 0.001); while the mean difference between the post-and pre-operative flexion was 11.14° (SEM = 1.3°; p < 0.0001) with flexion and radial deviation reaching 84.3% and 95.72% respectively of the unaffected wrist. The mean difference for the VAS score was -5.46 (SEM = 0.19; p < 0.0001). The mean post-operative grip strength of the affected side was 38.42 ± 10.27 kg (range 20-60 kg) as compared with mean pre-operative grip strength of 24.07 ± 10.51 kg (range 8-40 kg) (p < 0.0001). The mean post-operative grip strength of the operated side was 93.4% of the unaffected side. The DISI was corrected in all cases on post-operative radiographs. The mean difference between the post-and pre-operative SL angles was -8.95° (SEM = 1.28°; p < 0.0001). The mean post-operative DASH score was 8.3 ± 7.82 as compared with mean pre-operative DASH score of 46.04 ± 16.57 (p < 0.0001). There was a negative co-relation between the overall DASH score and the post-operative correction of the DISI deformity with a lower DASH score associated with increasing SL angles. Discussion The dorsal portion of the scapholunate ligament is critical for the stability scapholunate articulation, largely due to its attachment to the dorsal capsule. We have recently conducted a multi-centric anatomical study with international collaboration demonstrating the critical importance of this dorsal scapholunate complex. The all arthroscopic capsulo-ligamentous repair technique provides reliable results in addition to avoiding postoperative stiffness. The overall results at a mean follow-up period of more than 2 years in our series of young, active patients appear to be encouraging.

Dorsal wrist capsular tears in association with scapholunate instability: results of an arthroscopic dorsal capsuloplasty

Purpose The purpose of this study is to report the association of dorsal wrist capsular avulsion with scapholunate ligament instability and to evaluate the results of an arthroscopy-assisted repair. Methods We retrospectively reviewed 10 patients with a mean age of 39.1 years suffering from chronic dorsal wrist pain. They underwent a wrist arthroscopy with an evaluation of the scapholunate ligament complex from the radiocarpal and midcarpal compartments. An avulsion of the dorsal intercarpal ligament (DICL) from the scapholunate interosseous ligament (SLIL) was visible from the radiocarpal compartment in all cases, while the SLIL was intact. The DICL tear was repaired with an arthroscopy-assisted dorsal capsuloplasty. Patients were assessed preoperatively and postoperatively by the QuickDASH (Disabilities of the Arm, Shoulder, and Hand) questionnaire, by the Visual Analog Scale (VAS) for pain, and by a clinical and radiological examination. Results Preoperatively, all patients had reduced flexion and radial deviation of the affected wrist. On the lateral radiograph, 5 of the 10 patients showed an increase of the scapholunate angle (60 to 85°). The scapholunate instability was graded as Messina-European Wrist Arthroscopy Society (EWAS) II in five cases and as grade IIIB in five cases. A tear of the ulnar part of the triangular fibrocartilage complex (TFCC) was found in seven cases. At a mean followup of 16 months, the wrist range of motion (ROM), the grip strength, the QuickDASH, and the VAS of pain improved significatively. The scapholunate angle was normalized in all cases. Discussion Isolated tears of the DICL at its insertion from the dorsal part of the SLIL can be associated with scapholunate instability in the absence of an injury to the SLIL. The diagnosis is made arthroscopically. The arthroscopic dorsal capsuloplasty is a minimally invasive technique that provides short-term satisfactory results. Further studies are needed to determine whether repair of the DICL tear could prevent secondary destabilization of the scapholunate ligament complex. Level of evidence IV (case series) Diagnosis.

The EWAS Classification of Scapholunate Tears: An Anatomical Arthroscopic Study

Treatment of scapho-lunate (SL) injuries is still a challenge for the surgeon, especially in chronic cases. The aim of the study isto experimentally cut, specific portions of scapholunate ligament and extrinsic ligaments and check their corresponding arthroscopic finding in order to understand the pathogenesis and develop a new classification system which is an evolution of the present arthroscopic classifications. Materials and Methods Thirteen cadaver wrists were studied under arthroscopy. Different portions of the scapho-lunate ligament were subsequently sectioned. In group A the sectioning sequence was: anterior SLIOL, RSC, LRL, SLIOL's proximal and posterior, DIC, DRC ligament and ST ligaments (8 cases). In group B it was: SLIOL's posterior and proximal, DIC, SLIOL's anterior, LRL, RSCL, DRC, ST ligaments (5 cases). The anatomo-pathological findings after each sectioning were correlated to the classification system proposed (Table 1). Results In group A, stage 3A was obtained when SL ligament's volar and intermediate portion and/ or SC/LRL ligaments were sectioned. A stage 3C was obtained when section of posterior SLIOL was sectioned as well. A stage IV when the DIC was also sectioned. In group B a stage 3B was obtained by cutting intermediate, posterior portion of the SLIOL ligament and DIC. A stage 3C was obtained when the anterior part of the SLIOL was also sectioned. In all cases, sectioning of the SLIOL lead to a stage 3C only if associated with sectioning of at least one of the extrinsic stabilizers (DIC or SC/LRL). Sectioning of DIC and SC ligament, in addition to SLIOL led to an arthroscopic stage IV. When ST, DRC and TH ligaments were also sectioned significant radiological signs appeared (stage V). Conclusions This study helps us to understand the anatomo-pathological scapho-lunate lesions in their different stages of partial lesions. Commonly called scapho-lunate lesions are complex, involving also extrinsic ligaments.

Vascularized bone grafts for the treatment of carpal bone pathology

Primary bone healing fails to occur in 5-15 % of scaphoid bones that undergo fracture fixation. Untreated, occult fractures result in nonunion up to 12 % of the time. Conventional bone grafting is the accepted management in the treatment algorithm of scaphoid nonunion if the proximal pole is vascularized. Osteonecrosis of the proximal scaphoid pole intuitively suggests a need for transfer of the vascularized bone to the nonunion site. Scaphoid nonunion treatment aims to prevent biological and mechanical subsidence of the involved bone, destabilization of the carpus, and early degenerative changes associated with scaphoid nonunion advanced collapse. Pedicled distal radius and free vascularized bone grafts (VBGs) offer hand surgeons an alternative treatment option in the management of carpal bone nonunion. VBGs are also indicated in the treatment of avascular necrosis of the scaphoid (Preiser's disease), lunate (Kienböck's disease), and capitate. Relative contraindications to pedicled dorsal radius vascularized bone grafting include humpback deformity, carpal instability, or collapse. The free medial femoral condyle bone graft has offered a novel treatment option for the humpback deformity to restore geometry of the carpus, otherwise not provided by pedicled grafts. In general, VBGs are contraindicated in the setting of a carpal bone without an intact cartilaginous shell, in advanced carpal collapse with degenerative changes, and in attempts to salvage small or collapsed bone fragments. Wrist salvage procedures are generally accepted as the more definitive treatment option under such circumstances. This manuscript offers a current review of the techniques and outcomes of VBGs to the carpal bones.

Arthroscopic dorsal capsuloligamentous repair in chronic scapholunate ligament tears

This article discusses the preliminary results of treatment of chronic scapholunate lesions by arthroscopic dorsal capsuloligamentous repair, which does not require open exposure of the wrist capsule. Thirty six patients underwent arthroscopically assisted dorsal capsuloplasties. Sixteen had percutaneous pinning. Mean follow-up was at 11.4 months. The average arc of motion was 105°preoperatively and 120°postoperatively. The average grip strength attained 92% of the contralateral side. Most of the results were excellent-to-good. Seven professional athletes returned to preinjury level. Arthroscopic dorsal capsuloligamentous repair is a promising option, but a longer follow-up is necessary to confirm these results.