Association of lesions of the scapholunate interval with arthroscopic grading of scapholunate instability via the geissler classification

Comparing Patient-Reported Outcomes on Three-Ligament Tenodesis Between Partial and Complete Scapholunate Ligament Injuries: A Cohort Study

PURPOSE

Multiple studies report outcomes after 3-ligament tenodesis (3-LT) in treating traumatic scapholunate interosseous ligament injury (SLIL). However, investigators do not differentiate between patients with partial or complete SLIL injury. The relation between the extent of SLIL disruption and surgical outcomes and if this should be considered when treating a patient with SLIL injury remains unknown. We aimed to evaluate differences in patient-rated wrist evaluation (PRWE) scores, satisfaction and return to work between patients with partial or complete chronic traumatic SLIL injury treated with 3 ligament tenodesis at 12 months after surgery.

METHODS

All patients with chronic SLIL injury (partial and complete) who were treated with 3-LT at our clinic and received the same postoperative management between December 2011 and December 2019 were studied. Only patients who had completed the PRWE and return to work questionnaires preoperatively and 12 months after surgery were included. Patients were allocated to the partial (classified as Geissler 2 or 3) or complete SLIL injury group (classified as Geissler 4) by retrospectively assessing wrist arthroscopy reports.

RESULTS

Thirty-nine patients with partial and 90 with complete SLIL injuries were included. At 1-year follow-up, PRWE scores had significantly improved in both groups. When adjusting for clinical baseline characteristics, there was no statistically significant difference between patients with partial or complete SLIL injury. Patients with complete SLIL injury had a 70% higher return to work within the first 12 months after 3-LT; however, satisfaction with the treatment result was similar for both study groups 1 year after surgery.

CONCLUSIONS

Patients with complete and partial traumatic SLIL injury report better PRWE total scores at 12 months after 3-LT, but there was no statistically significant difference between the groups in PRWE scores or satisfaction with the treatment result.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Validation of the Clenched Fist View in Detecting Scapholunate Ligamentous Injury

BACKGROUND

The purpose of this study was to determine the predictive value of the clenched fist stress views in identifying scapholunate ligament injuries.

METHODS

An institutional review board-approved retrospective chart review was conducted of adult patients who underwent diagnostic arthroscopy with a ligamentous wrist injury from 2015 to 2020. Standard posteroanterior, lateral, and clenched fist stress radiographs were reviewed and scapholunate ligament gaps recorded.

RESULTS

A total of 124 patients were included, of which 88 had normal standard radiographs and clenched fist radiographs. The positive predictive value of the clenched fist view was 69%, whereas the negative predictive value was 58%. The sensitivity of the clenched fist view was 40%, while the specificity was 82%. Of those patients with a negative clenched fist view, 42% were found to have an arthroscopic Geissler classification of 3 or higher scapholunate ligament injury.

CONCLUSIONS

Despite the emphasis on stress radiographic views, a normal stress clenched fist view does not preclude arthroscopic findings of a Geissler class 3 or greater injury in symptomatic patients. The sensitivity of a clenched fist view is only 40%. These findings question the utility of stress radiographs when assessing for scapholunate ligament injuries.

Immunohistochemical Investigation of Mechanoreceptors Within the Injured Scapholunate Ligament

PURPOSE

Scapholunate ligaments (SLLs) play a well-established role in maintaining carpal alignment and kinematics, and are innervated with sensory mechanoreceptors located within the ligaments. They are involved in the afferent arc of dynamic wrist stability. The aim of this study was to describe the changes in these mechanoreceptor populations in injured SLLs.

METHODS

Injured SLLs were collected from human wrists at the time of SLL reconstruction or limited wrist fusion, where the ligament remnants would otherwise be discarded. These specimens were formalin-fixed and paraffin-embedded for immunohistochemical analysis to identify mechanoreceptors, which were then classified by type and location within the ligament.

RESULTS

A total of 15 ligaments were collected, with the interval from injury ranging from 39 days-20 years. Eleven ligaments were collected less than one year after injury, and four ligaments were collected two years or more after injury. A total of 66 mechanoreceptors were identified, with 50 mechanoreceptors identified in nine of the 11 specimens collected less than one year after injury. In this group, 54% of the mechanoreceptors resided in the volar subunit, 20% in the dorsal subunit, and 26% in the proximal subunit. Two of the four specimens collected two years or later after injury contained mechanoreceptors, all of which were located in the dorsal subunit. Increasing time from injury demonstrated a decline in mechanoreceptor numbers within the volar subunit.

CONCLUSIONS

Mechanoreceptors were consistently located in the SLL, particularly in the volar subunit of specimens collected less than one year after injury.

CLINICAL RELEVANCE

Ligament reconstruction techniques aim to primarily reconstitute the biomechanical function of the disrupted SLL; however, re-establishing the afferent proprioceptive capacity of the SLL may be a secondary objective. This suggests the need to consider the reconstruction of its volar subunit particularly in those managed within one year of injury.

Scaphoid, lunate and capitate kinematics in the normal and ligament deficient wrist: A bi-plane X-ray fluoroscopy study

The ligamentous structures of the wrist stabilise and constrain the interactions of the carpal bones during active wrist motion; however, the three-dimensional translations and rotations of the scaphoid, lunate and capitate in the normal and ligament deficient wrist during planar and oblique wrist motions remain poorly understood. This study employed a computer-controlled simulator to replicate physiological wrist motion by dynamic muscle force application, while carpal kinematics were simultaneously measured using bi-plane x-ray fluoroscopy. The aim was to quantify carpal kinematics in the native wrist and after sequential sectioning of the scapholunate interosseous ligament (SLIL) and secondary scapholunate ligament structures. Seven fresh-frozen cadaveric wrist specimens were harvested, and cycles of flexion-extension, radial-ulnar deviation and dart-thrower's motion were simulated. The results showed significant rotational and translational changes to these carpal bones in all stages of disruptions to the supporting ligaments (p < 0.05). Specifically, following the disruption of the dorsal SLIL (Stage II), the scaphoid became significantly more flexed, ulnarly deviated, and pronated relative to the radius, whereas the lunate became more extended, supinated and volarly translated (p < 0.05). Sectioning of the dorsal intercarpal (DIC), dorsal radiocarpal (DRC), and scaphotrapeziotrapezoid (STT) ligaments (Stage IV) caused the scaphoid to collapse further into flexion, ulnar deviation, and pronation. These findings highlight the importance of all the ligamentous attachments that relate to the stability of the scapholunate joint, but more importantly, the dorsal SLIL in maintaining scapholunate stability, and the preservation of the attachments of the DIC and DRC ligaments during dorsal surgical approaches. The findings will be useful in diagnosing wrist pathology and in surgical planning.

Assessing Diagnostic Accuracy of Four-dimensional CT for Instable Scapholunate Dissociation: The Prospective ACTION Trial

Background Timely treatment of scapholunate instability depends on early identification, but current imaging methods are either intricate or fail to demonstrate the dynamic stages. Purpose To calculate the diagnostic accuracy of four-dimensional (4D) CT for diagnosing instable scapholunate ligament (SLL) tears. Materials and Methods This prospective study enrolled consecutive participants with clinically suspected SLL tears who underwent 4D CT from July 2020 to May 2022. A historical study sample diagnosed at cineradiography served as a comparison, and wrist arthroscopy was the reference standard. Scapholunate joints greater than 3 mm were interpreted as instable at index 4D CT and cineradiography. Diagnostic accuracy was expressed as sensitivity and specificity. Areas under the receiver operating characteristic curve and cutoff values for both index tests were calculated. Intraclass correlation coefficients (ICCs) were computed to compare interrater reliability. Effective radiation doses at 4D CT were measured with thermoluminescent dosimeters. Results The study included 40 participants (mean age, 43 years ± 14 [SD]; 24 male) evaluated at 4D CT and 78 patients (mean age, 45 years ± 11; 50 male) historically evaluated at cineradiography. Four-dimensional CT helped detect instable tears in 26 of 35 participants (sensitivity, 74.3% [95% CI: 56.7, 87.5]. Cineradiography revealed instable tears in 52 of 63 patients (sensitivity, 82.5% [95% CI: 70.9, 91]). Four of five participants with stable scapholunate joints were identified at 4D CT (specificity, 80.0% [95% CI: 28.4, 99.5]), and 12 of 15 patients with stable SLLs were identified at cineradiography (specificity, 80.0% [95% CI: 51.9, 95.7]). Interrater agreement of radiologic measurements on 4D CT scans was good to excellent (ICC range, 0.89-0.96). The effective radiation dose ranged from 67 to 72 mSv at the wrist and was less than 1 mSv at the head. Conclusion Four-dimensional CT results are highly reproducible. Instable scapholunate joints greater than 3 mm were detected with a sensitivity of 74.3% and a specificity of 80% in an exploratory trial. Further evidence from larger randomized trials is warranted. German Register for Clinical Trials no. DRKS00021110 (Universal Trial Number U1111-1249-7884) Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Demehri and Ibad in this issue.

An algorithmic diagnostic approach to scapholunate ligament injuries based on comparison of X-ray examinations and arthroscopy in 414 patients

Conventional X-ray imaging is usually the first diagnostic assessment after clinical examination in case of suspected scapholunate interosseous ligament (SLIL) injury. Nevertheless, there is no consensus on the norms of the scapholunate distance (SLD) or carpal angles. Therefore, we aimed to determine the utility of static and dynamic radiographs in the diagnostic of an SLIL injury in comparison with the reference standard arthroscopy. We retrospectively analyzed the preoperative X-ray series and surgical records of arthroscopies of 414 patients. Radiological assessment included conventional static X-rays in the posteroanterior (PA) projection, clenched fist views in ulnar and radial deviations, in which the SLD at the midportion of the scapholunate (SL) joint was measured. The scapholunate angle (SLA) and radiolunate angle (RLA) were measured on lateral wrist radiographs. Receiver operating characteristic (ROC) curves were created to determine possible cut-off points of the radiological indices for the diagnosis of SLIL injury. Further, a logistic regression with the parameters having the highest area under the curve (AUC) was calculated. We found that SLD in ulnar inclination (AUC= 0.774), SLD in PA projection (AUC = 0.748), and SLA (AUC = 0.737) had the highest diagnostic value. The AUC of the combination of these three parameters was 0.822 for all patients with any SLIL lesion and 0.850 for patients with SLIL lesions of 3-4 Geissler grade. Further investigation of SLIL pathology would be appropriate in the case of SLD in ulnar inclination of 2.7 mm, SLD in PA projection of 1.9 mm and SLA of 63°.

Scaphometacarpal Stabilization Technique for Repairable Scapholunate Injury

Despite the numerous techniques (both arthroscopic and open) for the treatment of acute scapholunate instability, there is no consensus on which one results in better healing of the ligaments. In the present work, we describe a new surgical technique to achieve stability of the scaphoid that enables the reduction inflexion and pronation of this bone when dissociation is produced. Using a high-strength suture wire with double cortical button anchor (Mini TightRope, Arthrex, Naples, FL, US, or MicroLink, Conmed, Largo, FL, US) stabilization of the scaphoid is achieved to protect ligament healing without the need for postoperative immobilization.

ACTION trial: a prospective study on diagnostic Accuracy of 4D CT for diagnosing Instable ScaphOlunate DissociatioN

Background

Early detection of scapholunate ligament (SLL) tears is essential after minor and major trauma to the wrist. The differentiation between stable and instable injuries determines therapeutic measures which aim to prevent osteoarthritis. Arthroscopy has since been the diagnostic gold standard in suspected SLL tears because non-invasive methods have failed to exclude instable injuries reliably. This prospective study aims to determine the diagnostic accuracy of dynamic, 4D computed tomography (CT) of the wrist for diagnosing instable SLL tears.

Methods

Single center, prospective trial including 40 patients with suspected SLL tears scheduled for arthroscopy. Diagnostic accuracy of 4D CT will be tested against the reference standard arthroscopy. Radiologists will be blinded to the results of arthroscopy and hand surgeons to radiological reports. A historical cohort of 80 patients which was diagnosed using cineradiography before implementation of 4D CT at the study site will serve as a comparative group.

Discussion

Static imaging lacks the ability to detect instable SLL tears after wrist trauma. Dynamic methods such as cineradiography and dynamic magnetic resonance imaging (MRI) are complex and require specific technical infrastructure in specialized centers. Modern super-fast dual source CT scanners are gaining popularity and are being installed gradually in hospitals and ambulances. These scanners enable dynamic imaging in a quick and simple manner. Establishment of dynamic 4D CT of the wrist in patients with suspected SLL tears in in- and outpatient settings could improve early detection rates. Reliable identification of instable injuries through 4D CT scans might reduce the number of unnecessary diagnostic arthroscopies in the future.

Trial registration

This study was registered prospectively at the German Clinical Trials Register (DRKS) DRKS00021110. Universal Trial Number (WHO-UTN): U1111–1249-7884.

Scapholunate Diastasis in Distal Radius Fractures: Fracture Pattern Analysis on CT Scans

Objectives  Our understanding of distal radius fractures with concomitant scapholunate (SL) diastasis primarily comes from plain radiographs and arthroscopy. The clinical implications of SL diastasis are not clear. The aim of this study is to describe fracture characteristics of distal radius fractures on computed tomography (CT) scans in patients with distal radius fractures and static SL diastasis. Methods  We queried our institutional databases to identify patients who were treated for a distal radius fracture, had a CT scan with a wrist-protocol, and static SL diastasis on their CT scan. Our final cohort consisted of 26 patients. We then collected data on their demographics, injury, treatment, evaluated injury patterns, and measured radiographic SL characteristics. Our study cohort consisted of 11 men (42%) and almost half of our cohort ( n  = 12; 46%) had a high-energy mechanism of injury. The majority of the patients ( n  = 20; 77%) had operative treatment for their distal radius fracture and two patients (7.7%) had operative treatment of their SL injury. Results  The mean SL distance was 3.5 ± 1.1 mm. Twenty patients (77%) had an intra-articular fracture. In these patients, we observed three patterns: (1) scaphoid facet impaction; (2) lunate facet impaction; and (3) no relative impaction. We observed other injury elements including rotation of the radial styloid relative to the lunate facet and partial carpal subluxations. Conclusion  Static SL dissociation in the setting of distal radius fractures may be an indication of a complex injury of the distal radius, which may not be directly apparent on plain radiography. If these radiographs do not demonstrate impaction of the lunate or scaphoid facet, a CT scan may be warranted to have a more detailed view of the articular surface. Level of Evidence  This is a Level III, diagnostic study.

Chronic Scapholunate Interosseous Ligament Disruption: A Systematic Review and Meta-Analysis of Surgical Treatments

Background: Although many techniques have been described, there is no clear optimal surgical treatment for chronic scapholunate interosseous ligament (SLIL) disruption. Methods: We identified 255 articles reporting outcomes of SLIL reconstruction. Of these, 40 studies (978 wrists) met eligibility requirements and reported sufficient data on radiographic outcomes to be included in the study. The mean and standard deviation of preoperative and follow-up assessments including scapholunate gap (SLG) and scapholunate angle (SLA) were used to calculate pooled standardized mean differences (SMD) with 95% confidence intervals (CIs). For other radiographic or clinical outcomes, there were not enough reported data to calculate a pooled effect size, and pooled nonstandardized comparisons were made. Results: The SMD between preoperative and postoperative SLA in tenodesis reconstruction was 0.7 (CI, 0.29 to 1.11, P = .001) and 0.04 (CI, -0.27 to 0.38, P = .8) for capsulodesis reconstruction. For SLG, tenodesis demonstrated an SMD of 1.1 (CI, 0.6 to 1.55, P < .001) compared with 0.1 (CI, -0.36 to 0.59, P = .6) for capsulodesis reconstruction. Tenodesis had a significant improvement compared with capsulodesis in SLA (P = .01) and SLG (P = .005). Tenodesis also showed improvement in grip strength and Disabilities of the Arm, Shoulder and Hand scores. Conclusions: Comparing preoperative and postoperative radiographic measurements, tenodesis reconstruction demonstrated significantly improved SLG and SLA relative to capsulodesis. Interpreted in the context of the limitations, existing data demonstrates some benefit of tenodesis reconstruction.

Dorsal Extrinsic Ligament Injury and Static Scapholunate Diastasis on Magnetic Resonance Imaging Scans

PURPOSE

Current biomechanical data suggest that static scapholunate (SL) ligament dissociation occurs only when there is loss of competence of the extrinsic ligaments either acutely or with attenuation over time. We aimed to identify whether patients with an SL gap greater than 2 mm demonstrated concomitant dorsal radiocarpal ligament (DRC) and dorsal intercarpal ligament (DIC) ligament changes on magnetic resonance imaging (MRI) scans that were identified as having an SL ligament tear.

METHODS

We included 90 patients who had a posttraumatic MRI scan of the wrist diagnosed with an SL injury. We recorded basic demographics; 2 attending fellowship-trained musculoskeletal radiologists evaluated the integrity of the SL, DRC, and DIC ligaments and graded these as normal, low-grade injury (sprain or partial tear) or full-thickness tear. The association between the integrity of the DRC and DIC ligaments and the presence of a scapholunate gap of 2 mm or greater was analyzed.

RESULTS

A total of 48 patients (53%) had an SL distance of 2 mm or greater on MRI. Of these patients, 28 (58%) had a partial or total tear of the DIC and/or DRC ligament. Compared with patients with an SL interval less than 2 mm, patients with an SL interval 2 mm or greater more often demonstrated DIC signal change (31% vs 12%), DRC signal change (52% vs 14%), or combined or isolated DIC and/or DRC signal change (52% vs 14%).

CONCLUSIONS

Dorsal extrinsic ligaments demonstrate MRI signal change suggestive of acute or chronic injury in patients with an SL interval 2 mm or greater more often than in patients with an SL interval less than 2 mm. These results reinforce that MRI findings of SL ligament tear need to be interpreted in a larger context, perhaps with additional attention to the DIC and DRC appearance upon MRI. In addition, MRI evaluation of dorsal extrinsic ligaments may aid in clinical decision-making for patients with SL injury.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Surgical outcomes of chronic isolated scapholunate interosseous ligament injuries: a systematic review of 805 wrists

Background

Management of chronic isolated scapholunate interosseous ligament (SLIL) injuries has generated a substantial volume of low-quality literature with descriptions of multiple new surgical techniques, and the impact of instability pattern and the optimal surgical technique remain unclear. The primary goal of this review was to compare clinical, radiographic and patient-rated outcomes between current surgical techniques.

Methods

We performed a systematic literature search using multiple databases. We analyzed clinical, radiographic and patient-reported outcomes. We used a fixed-effects model weighted by sample size with combined outcomes estimated via least squares means with 95% confidence intervals. We also performed a subgroup analysis of static versus dynamic instability.

Results

We assessed 805 procedures from 37 study groups, with 429 procedures used in subgroup analysis. There were no statistically significant differences in outcomes between surgical techniques or in subgroup analysis. Overall, postoperative wrist flexion and pain scores decreased, and grip strength and patient-rated outcomes improved.

Conclusion

Compared to overall preoperative values, modest improvements in pain score, grip strength and functional outcome scores were obtained from a range of reconstructive procedures performed for chronic isolated SLIL injuries. No significant differences could be ascertained between surgical techniques, potentially owing to the low quality of evidence and procedure heterogeneity. This study provides accurate preoperative reference values for future studies, highlights the controversial clinical impact of instability classification, and the need for higher-quality multicentre or collaborative trials to improve our understanding and management of this common injury.

Incidence and Functional Outcomes of Scapholunate Diastases Associated Distal Radius Fractures: A 2-year Follow-Up Scapholunate Dissociation

BACKGROUND

The Scapholunate Interosseous Ligament (SLIL) is the first intrinsic carpal ligament to be injured in wrist trauma, present in up to 64% of the distal radius fractures. However, it remains unclear what patients develop symptoms, making primary treatment of these injuries accompanying distal radius fractures remains questionable.

OBJECTIVE

The aim of this study was to evaluate the functional outcomes of patients with scapholunate diastasis associated with distal radius fractures.

METHODS

We evaluated 391 patients with a distal radius fracture. Using Computer Tomography (CT) scans the scapholunate interval was measured. We identified 14 patients with an SLD (>3mm) of the injured wrist, which underwent a CT-scan of the contralateral wrist. To evaluate the functional outcomes at a mean follow up of 136±90 weeks, we used the Quick Disabilities of the Arm, Shoulder and Hand (qDASH) Score.

RESULTS

There were 8 patients with bilateral SLD and 6 patients with unilateral SLD. Five patients had a qDASH score of 0 and one patient showed a qDASH score of 18.2. The patient with a poor score had bilateral preexisting osteoarthritis of the wrist. No patient had additional surgery of the SLIL.

CONCLUSION

In patients with distal radius fractures, more than half of the 14 patients with an SL gap on CT had widening on the contralateral side. It is therefore worthwhile to image the contralateral wrist before diagnosing a SLD. The patients with unilateral SLD should not be surgically treated at initial presentation because they may have good functional outcomes after a follow up of 2 years.

Early controlled mobilization using dart-throwing motion with a twist for the conservative management of an intra-articular distal radius fracture and scapholunate ligament injury: A case report

This case describes an early controlled mobilization (ECM) approach that uses dart-throwing motion (DTM) with a twist orthoses as an alternative to immobilization for conservative management of a minimally displaced and intra-articular distal radius styloid fracture with an associated scapholunate ligament injury in a 47-year-old female health care administrator (JP). Pain-free active DTM began at day 10 (5 times/d) with a dynamic DTM with a twist orthosis worn during the day from weeks 3 to 6. At 6 weeks, JP had pain-free functional mobility and strength with minimal limitation in household and occupational activities, returning to her normal sporting activities by 3 months. ECM led to rapid return of normal functioning in the short term with no apparent impact on intermediate outcomes at 8 months. This case allows hand therapists to consider a similar ECM approach for the management of similar injuries in their patients.

LEVEL OF EVIDENCE

Level 5 and case report.