Arthroscopic Classification of the Lesions of the Dorsal Capsulo-Scapholunate Septum (DCSS) of the Wrist

Dorsal wrist ganglion: clinical and imaging correlation in symptomatic population based on high-field MRI

OBJECTIVES

To determine prevalence in the symptomatic population of dorsal mucoid cysts centered on dorsal capsuloscapholunate septum (DCSS) using high-field magnetic resonance imaging (MRI) for anatomoclinical and epidemiological correlations.

MATERIALS AND METHODS

This single-center retrospective study analyzed all 3-Tesla MRIs consecutively performed for painful wrists in 295 patients. Two blinded readers performed measurements. The protocol included T1 spin echo and 3D proton density sequences with fat saturation. Inter-observer reliability was assessed using kappa and intra-class correlation coefficients for cyst detection and volumetry, respectively. Disagreements concerning cyst detection were resolved by a consensus reading. Cyst size, relationship to extrinsic and scapholunate ligaments (SL), continuity of SL, minimum distance to the posterior interosseous nerve (PIN), cyst communication with joint, and anatomical classifications of cysts were analyzed. Correlation tests were performed to assess associations.

RESULTS

Two-hundred ninety-five patients (mean age 39.6 +/- 15.6 (standard deviation), 161 males) were evaluated for detection of dorsal wrist cysts identified in 150/295. In this subgroup, the mean age was 38.7 years (15-75), the sex ratio of 0.6 (59% women), and the median volume cyst of 8.7 mm3 (0.52-2555). Cyst detection, volume, and major axis measurements showed very high agreement between observers, respectively, 0.89, 0.96, and 0.91. 42 patients had dorsal SL pain. A weak negative correlation was found between distance to PIN and dorsal SL pain (r = -0.2415; p < 0.05) and a weak positive correlation between Guérini's classification and dorsal SL pain (r = 0.2466; p < 0.05).

CONCLUSION

High-field MRI is the modality of choice for the detection, anatomical, and volumetric assessment of dorsal cysts. Preoperative assessment will be aided by the proposed revised anatomical classification.

CLINICAL RELEVANCE STATEMENT

High-field MRI is the modality of choice for the anatomical study of dorsal ganglion cysts. It allows the radiologist to accurately describe the anatomical relationships, size, and visibility of the pedicle, essential information for the surgeon's preoperative assessment.

KEY POINTS

Dorsal mucoid wrist ganglion is a condition for which prevalence remains to be determined. High-field MRI is a reproducible imaging modality for the detection and assessment of dorsal wrist cysts. High-field MRI has a key role in the preoperative management of dorsal mucoid cysts.

Correlation between dorsal capsulo-scapholunate septum (DCSS) lesion and predynamic scapholunate instability

OBJECTIVE

Scapholunate instability is the most common ligament injury of the wrist. In case of predynamic instability, diagnosis can be difficult, even under arthroscopy. Scapholunate instability is not the result of an isolated injury to the scapholunate interosseous ligament. Scapholunate stability is dependent not only on the scapholunate ligament, but on a complex that is comprising intrinsic and extrinsic ligaments. The dorsal capsule-scapholunate septum (DCSS) is one of the secondary stabilizers of the scapholunate complex. The objective of the present study was to investigate the correlation between DCSS lesion and predynamic scapholunate instability.

METHOD

A prospective multicenter study included patients who underwent wrist arthroscopy for traumatic wrist. Arthroscopic DCSS lesion stage and instability according to European Wrist Arthroscopy Society stage were assessed.

RESULTS

Twenty-seven subjects were included. We found a significant correlation between pathological DCSS and predynamic scapholunate instability and a correlation between DCSS lesion severity and instability level.

CONCLUSION

Isolated DCSS lesion should be considered a predictive factor for predynamic instability.

Scapholunate Instability: Diagnosis and Management - Anatomy, Kinematics, and Clinical Assessment - Part I

Injuries to the scapholunate joint are the most frequent cause of carpal instability. The sequelae of these injuries account for considerable morbidity, and if left untreated, may lead to scapholunate advanced collapse and progressive deterioration of the carpus. Rupture of the scapholunate interosseous ligament and its critical stabilizers causes dyssynchronous motion between the scaphoid and lunate. Additional ligament injury or attenuation leads to rotary subluxation of the scaphoid and increased scapholunate gap. Intervention for scapholunate instability is aimed at halting the degenerative process by restoring ligament integrity and normalizing carpal kinematics. In the first section of this review, we discuss the anatomy, kinematics, and biomechanical properties of the scapholunate ligament as well as its critical ligament stabilizers. We provide a foundation for understanding the spectrum of scapholunate ligament instability and incorporate meaningful new anatomical insights that influence treatment considerations. The purpose is to provide an update regarding the anatomy of the scapholunate ligament complex, importance of the critical ligament stabilizers of the proximal carpal row, introduction of safe technique to surgically expose the scaphoid and lunate, as well as pathoanatomy as it pertains to the treatment of scapholunate dissociation. In the second section of this review, we propose a novel ligament-based treatment algorithm based on the stage of injury, degree and nature of ligament damage, and presence of arthritic changes.

Wide arthroscopic dorsal capsuloligamentous repair in patients with severe scapholunate instability

A conventional arthroscopic capsuloligamentous repair is a reliable surgical solution in most patients with scapholunate instability. However, this repair does not seem to be sufficient for more advanced injuries. The aim of this study was to evaluate the functional results of a wide arthroscopic dorsal capsuloligamentous repair (WADCLR) in the management of severe scapholunate instability. This was a prospective single-centre study undertaken between March 2019 and May 2021. The primary outcome was the evaluation of the reduction of the radiological deformity and the functional outcomes after WADCLR. A secondary outcome was the evaluation of the effectiveness of this technique in patients with the most severe instability (European Wrist Arthroscopy Society (EWAS) stage 5). The patients were reviewed postoperatively at three, six, and 12 months. The study included 112 patients (70 male and 42 female). Their mean age was 31.6 years (16 to 55). A total of three patients had EWAS stage 3A injuries, 12 had stage 3B injuries, 29 had stage 3C injuries, 56 had stage 4 injuries, and 12 had stage 5 injuries. There was a significant improvement of the radiological signs in all patients with a return to normal values. There was also a significant improvement in all aspects of function except for flexion, in which the mean increase was negligible (0.18° on average). There was also a significant improvement in all criteria for patients with a stage 5 injury, except for some limitation of extension, flexion, and radial and ulnar deviation, although these showed a trend towards improvement (except for flexion). WADCLR is a minimally invasive, easy, and reproducible technique with few complications, offering a clear improvement in function and a reduction in the radiological deformity at one year postoperatively.

Volar Ganglion Cyst and Echo-Guided Assistance for the Arthroscopic Removal

The ganglion of the wrist is very common but with uncertain prognosis. The arthroscopic resection seems to improve the result compared with open procedure, in decreasing recurrence and morbidity. Volar ganglions are close to the radial artery, the flexor pollicis longus tendon, and even the median nerve. Ultrasonography combined with arthroscopy offers incomparable safety for the resection of volar ganglions. The technical steps of this combined procedure are described, and the first published series are discussed.

Extrinsic and Intrinsic Ligaments of the Wrist

Carpal stability depends on the integrity of both intra-articular and intracapsular carpal ligaments. In this review, the role of the radial-sided and ulnar-sided extrinsic and intrinsic ligaments is described, as well as their advanced imaging using magnetic resonance arthrography (MRA) and contrast-enhanced magnetic resonance imaging (MRI) with three-dimensional (3D) scapholunate complex sequences and thin slices. In the last decade, the new concept of a so-called "scapholunate complex" has emerged among hand surgeons, just as the triangular ligament became known as the triangular fibrocartilage complex (TFCC).The scapholunate ligament complex comprises the intrinsic scapholunate (SL), the extrinsic palmar radiocarpal: radioscaphocapitate (RSC), long radiolunate (LRL), short radiolunate (SRL) ligaments, the extrinsic dorsal radiocarpal (DRC) ligament, the dorsal intercarpal (DIC) ligament, as well as the dorsal capsular scapholunate septum (DCSS), a more recently described anatomical structure, and the intrinsic palmar midcarpal scaphotrapeziotrapezoid (STT) ligament complex. The scapholunate (SL) ligament complex is one of the most involved in wrist injuries. Its stability depends on primary (SL ligament) and secondary (RSC, DRC, DIC, STT ligaments) stabilizers.The gold standard for carpal ligament assessment is still diagnostic arthroscopy for many hand surgeons. To avoid surgery as a diagnostic procedure, advanced MRI is needed to detect associated lesions (sprains, midsubstance tears, avulsions and chronic fibrous infiltrations) of the extrinsic, midcarpal and intrinsic wrist ligaments, which are demonstrated in this article using 3D and two-dimensional sequences with thin slices (0.4 and 2 mm thick, respectively).

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.

Optimal management of scapholunate ligament injuries

Scapholunate ligament (SLL) injuries are a common cause of wrist pain and instability. Treatment of SLL injuries requires intricate understanding of wrist anatomy and biomechanics. Mindful physical exam and appropriate diagnostic studies can orient the surgeon to the defined stage of injury. Review of the literature on each treatment by stage can prepare the upper extremity surgeon to provide the best evidence-based care. The optimal management of SLL injuries should result in a stable, painless wrist.