Introduction. The human wrist is a highly complex joint, offering extensive motion across various planes. This study investigates scapholunate ligament (SLL) injuries’ impact on wrist stability and arthritis risks using cadaveric experiments and the finite element (FE) method. It aims to validate experimental findings with FE analysis results. Method. The study utilized eight wrist specimens on a custom rig to investigate Scapho-Lunate dissociation. Contact pressure and flexion were measured using sensors. A CT-based 3D geometry reconstruction approach was used to create the geometries needed for the FE analysis. The study used the Friedman test with pairwise comparisons to assess if differences between testing conditions were statistically significant. Result. The study found significant variations in scaphoid and lunate bone movement based on ligament condition. Full tears increased scapholunate distance in the distal-proximal direction and decreased in the medial-lateral direction. Lunate angles shifted from flexion to extension with fully torn ligaments. Conversely, the scaphoid shifted significantly from extension to flexion with full tears. A proximal movement was observed in the distal-proximal direction in all groups, with significant differences in the partial tear group. Lateral deviation of the scaphoid and lunate occurred with ligament damage, being more pronounced in the partial tear group. All groups exhibited statistically significant movement in the volar direction, with the full tear group showing the least movement. Also, radiocarpal joint and finger contact pressure and contact area were studied. Whereas the differences in contact area were not significant, scapholunate ligament tears resulted in significantly decreased finger contact pressures. FEA confirmed these findings, showing notable peak radiocarpal contact pressure differences between intact and fully torn ligaments. Conclusion. Our study found that SLL damage alters wrist stability, potentially leading to early arthritis. The FEA model confirmed these findings, indicating the potential for the clinical use of computer models from CT scans for treatment planning

The October 2024 Wrist & Hand Roundup360 looks at: Circumferential casting versus plaster splinting in preventing redisplacement of distal radial fractures; Comparable outcomes for operative versus nonoperative treatment of scapholunate ligament injuries in distal radius fractures; Perceived pain during the reduction of Colles fracture without anaesthesia; Diagnostic delays and physician training are key to reducing scaphoid fracture nonunion; Necrotizing fasciitis originating in the hand: a systematic review and meta-analysis; Study design influences outcomes in distal radial fracture research; Long-term results of index finger pollicization for congenital thumb anomalies: a systematic review; Enhancing nerve injury diagnosis: the evolving role of imaging and electrodiagnostic tools.

Aims

The study aimed to assess the clinical outcomes of arthroscopic debridement and partial excision in patients with traumatic central tears of the triangular fibrocartilage complex (TFCC), and to identify prognostic factors associated with unfavourable clinical outcomes.

There is currently no commercially available and clinically successful treatment for scapholunate interosseous ligament rupture, the latter leading to the development of hand-wrist osteoarthritis. We have created a novel biodegradable implant which fixed the dissociated scaphoid and lunate bones and encourages regeneration of the ruptured native ligament. To determine if scaphoid and lunate kinematics in cadaveric specimens were maintained during robotic manipulation, when comparing the native wrist with intact ligament and when the implant was installed. Ten cadaveric experiments were performed with identical conditions, except for implant geometry that was personalised to the anatomy of each cadaveric specimen. Each cadaveric arm was mounted upright in a six degrees of freedom robot using k-wires drilled through the radius, ulna, and metacarpals. Infrared markers were attached to scaphoid, lunate, radius, and 3rd metacarpal. Cadaveric specimens were robotically manipulated through flexion-extension and ulnar-radial deviation by ±40° and ±30°, respectively. The cadaveric scaphoid and lunate kinematics were examined with 1) intact native ligament, 2) severed ligament, 3) and installed implant. Digital wrist models were generated from computed tomography scans and included implant geometry, orientation, and location. Motion data were filtered and aligned relative to neutral wrist in the digital models of each specimen using anatomical landmarks. Implant insertion points in the scaphoid and lunate over time were then calculated using digital models, marker data, and inverse kinematics. Root mean squared distance was compared between severed and implant configurations, relative to intact. Preliminary data from five cadaveric specimens indicate that the implant reduced distance between scaphoid and lunate compared to severed configuration for all but three trials. Preliminary results indicate our novel implant reduced scapho-lunate gap caused by ligament transection. Future analysis will reveal if the implant can achieve wrist kinematics similar to the native intact wrist

Aims

Wrist arthroscopy is a standard procedure in hand surgery for diagnosis and treatment of wrist injuries. Even though not generally recommended for similar procedures, general administration of perioperative antibiotic prophylaxis (PAP) is still widely used in wrist arthroscopy.

Aims

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.

Chauffeur fractures or isolated radial styloid fractures (IRSF) are known to be associated with scapholunate ligament (SL) injuries. Diagnosis without arthroscopic confirmation is difficult in acute fractures. Acute management of this injury with early repair may prevent the need for more complex reconstructive procedures for chronic injuries. We investigated if all IRSF should be assessed arthroscopically for concomitant SL injuries. We performed a prospective cohort study on patients above the age of 16, presenting to the Gold Coast University Hospital with an IRSF, over 2 years. Plain radiographs and computerized tomography (CT) scans were performed. All patients had a diagnostic wrist arthroscopy performed in addition to an internal fixation of the IRSF. Patients were followed up for at least 3 months post operatively. SL repair was performed for all Geissler Grade 3/4 injuries. 10 consecutive patients were included in the study. There was no radiographic evidence of SL injuries in all patients. SL injuries were identified arthroscopically in 60% of patients and one third of these required surgical stabilisation. There were no post operative complications associated with wrist arthroscopy. We found that SL injuries occurred in 60% of IRSF and 20% of patients require surgical stabilisation. This finding is in line with the literature where SL injuries are reported in up to 40-80% of patients. Radiographic investigations were not reliable in predicting possible SL injuries in IRSF. However, no SL injuries were identified in undisplaced IRSF. In addition to identifying SL injuries, arthroscopy also aids in assisting and confirming the reduction of these intra-articular fractures. In conclusion, we should have a high index of suspicion of SL injury in IRSF. Arthroscopic assisted fixation should be considered in all displaced IRSF. This is a safe additional procedure which may prevent missed SL injuries and their potential sequelae

Introduction and Objective. Scapholunate instability is the most common cause of carpal instability. When this instability is left untreated, the mechanical relationship between the carpal bones is permanently disrupted, resulting in progressive degenerative changes in the radiocarpal and midcarpal joints. Different tenodesis methods are used in the treatment of acute or early chronic reducible scapholunate instability, where arthritis has not developed yet and the scapholunate ligament cannot be repaired. Although it has been reported that pain is reduced in the early follow up in clinical studies with these methods, radiological results differ between studies. The deterioration of these radiological parameters is associated with wrist osteoarthritis as previously stated. Therefore, more studies are needed to determine the tenodesis method that will improve the wrist biomechanics better and will last longer. In our study, two new tenodesis methods, spiral antipronation tenodesis, and anatomic front and back reconstruction (ANAFAB) were radiologically compared with triple ligament tenodesis (TLT), in the cadaver wrists. Materials and Methods. The study was carried out on a total of 16 fresh frozen cadaver wrists. Samples were randomly allocated to the groups treated with 3 different scapholunate instability treatment methods. These are TLT (n: 6), spiral antipronation tenodesis (n: 5) and ANAFAB tenodesis (n: 5) groups. In all samples SLIL, DCSS, STT, DIC, RSC and LRL ligaments were cut in the same way to create scapholunate instability. Wrist CT scans were taken on the samples in 4 different states, in intact, after the ligaments were cut, after the reconstruction and after the movement cycle. In all of these 4 states, wrist CTs were taken in 6 different wrist positions. For every state and every position through tomography images; Scapholunate (SL) distance, Scapholunate (SL) angle, Radioscaphoid (RS) angle, Radiolunate (RL) angle, Capitolunate (CL) angle, Dorsal scaphoid translation (Dt) measurements were made. Results. Scapholunate distances means were different between intact and cut states only in neutral and clenched fist positions for all groups (p values <0.001). Mean differences were similar between the groups (p > 0.100). In neutral position, for SL center distance, mean difference between cut and reconstruction states were not different between the groups (p=0.497) but it was noted that only TLT group could not restore to the intact state. In neutral position, for SL angle, compared with the cut state, TLT and ANAFAB significantly reduced the angle (TLT: 20° (p=0.005), ANAFAB: 28° (p<0.001)) whereas antipronation tenodesis could not (13°, p=0.080). In clenched fist position, for SL angle, compared with the intact state, only ANAFAB group restored the angle, TLT and antipronation groups were significantly worse than the intact state (TLT: p<0.001, antipronation: p=0.001). In clenched fist position, for RL angle, compared with the intact state, ANAFAB and TLT groups restored the angle but antipronation group was significantly worse than the intact state (p<0.001). In neutral position, for RS angle, compared with the cut state, only ANAFAB significantly reduced the angle (11°, p<0.001) whereas TLT and antipronation groups could not (TLT: 6° (p=0.567), antipronasyon: 4° (p=0.128). Conclusions. In the presence of severe scapholunate instability in which a several number of secondary stabilizers are injured, the ANAFAB tenodesis method may be preferred to the classical method, TLT tenodesis. The results of spiral antipronation tenodesis were not better than the TLT

Aims

To determine the role of early MRI in the management of suspected scaphoid fractures.

Aims. The purpose was to evaluate early clinical, patient-reported, and radiological outcomes of the scapholunate ligament 360° tenodesis (SL 360) technique for treatment of scapholunate (SL) instability. Methods. We studied the results of nine patients (eight males and one female with a mean age of 44.7 years (26 to 55)) who underwent the SL 360 procedure for reducible SL instability between January 2016 and June 2019, and who were identified from retrospective review of electronic medical records. Final follow-up of any kind was a mean of 33.7 months (12.0 to 51.3). Clinical, radiological, and patient-reported outcome data included visual analogue scale (VAS) for pain, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH), Mayo Wrist Score (MWS), and Patient-Rated Wrist Examination (PRWE). Means were analyzed using paired t-test. Results. Before surgery, patients with SL instability were significantly impaired with respect to wrist flexion, extension, and grip strength (mean flexion, 51° (20° to 85°) vs 73° (45° to 90°); mean extension, 46° (15° to 70°) vs 66° (45° to 80°); mean grip strength, 25 kg (20 to 31) vs 50 kg (35 to 68) compared to the unaffected side). The mean SL gap (4.9 mm (2.3 to 7.3) vs 2.1 mm (1.6 to 2.9)) and mean SL angle (71° (59° to 105°) vs 50° (38° to 64°) were also significantly greater in the affected wrist. At final follow-up, there was mean improvement regarding clinical, radiological, and functional outcomes comparing preoperative to final postoperative values for the VAS for pain scale, QuickDASH, MWS, PRWE, and SL gap and SL angle. Conclusion. In our small series, the SL 360 procedure for reducible SL instability has favourable early clinical, patient-reported, and radiological outcomes at a mean of 33.7 months (12.0 to 51.3). The suture tape and tendon construct confers robust stability, permitting earlier mobilization without the inherent disadvantages of Kirschner wire stabilization. Cite this article: Bone Joint J 2021;103-B(5):939–945

Abstract. Objectives. The scapholunate interosseous ligament (SLIL) has a unique C-shape following the arc of the scaphoid and lunate surfaces from distal dorsal around to distal volar. This ligament comprises of three subregions: dorsal, proximal and volar. The SLIL enthesis, a specialized region where this ligament attaches to the scaphoid and lunate, has not previously been studied despite its important mechanical function in the biomechanics of the wrist joint. This study therefore aims to compare the histomorphological differences between the SLIL subregions, including at their entheses. This study will examine the qualitative and quantitative differences between the three subregions, as well as between the scaphoid and lunate attachments. Methods. Twelve fresh-frozen human cadaveric wrists were dissected and the gross dimensions of each SLIL subregion measured. Subregions were then histologically processed for qualitative and quantitative morphological and compositional analyses, including quantification of enthesis calcified fibrocartilage (CF) area. Results. From the gross measurements taken, the dorsal subregion was the thickest. There were no significant differences in lengths and widths between the three subregions. Qualitatively, the dorsal and volar subregions had fibrocartilaginous entheses while the proximal subregion inserted into cortical bone via articular cartilage. Quantitatively, the dorsal subregion had significantly more CF than the volar subregion. There was no significant difference in the enthesis CF between scaphoid and lunate attachments in the three subregions. Conclusions. There are significant histomorphological differences between the SLIL subregions. The dorsal subregion has the largest amount of CF, which is consistent with the greater biomechanical force subjected to this subregion compared to the other subregions. This result confirms that the dorsal subregion is the strongest of the three subregions. The similar histomorphology of the ligament at the scaphoid and lunate entheses suggests that similar biomechanical forces are applied to both attachments. Declaration of Interest. (a) fully declare any financial or other potential conflict of interest