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

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

Purpose: The mechanical behavior of human scapholunate ligaments is not described well in the literature regarding torsion. Presently, intact scapholunate specimens were mechanically tested in torsion to determine if any tensile forces were generated as a result. Method: Scapholunate specimens (n=19) were harvested and inspected visually. Scaphoid and lunate bones were potted in square chambers using epoxy cement. The interposing ligaments remained exposed. Specimens were mounted in a specially designed test jig and remained at a fixed axial length during testing. Using angular displacement control, ligaments were subjected to a torsional motion regime that included cyclic preconditioning (25 cycles, 1 Hz, triangular wave, 5 deg max), ramp-up to 15 deg at 180 deg/min, stress relaxation for 120 sec duration, ramp-down to 0 angulation at 180 deg/min, rest period for 5–10 minutes, and torsion-to-failure at 180 deg/min. Torque and axial tension were monitored simultaneously. Results: Tests showed a coupled linear relationship between applied torsion and the resultant tensile forces generated for the ligament during ramp-up (Torsion/Tension Ratio = 38.86 +/− 29.00 mm, Linearity Coefficient R-squared = 0.89 +/− 0.15, n=19), stress relaxation (Ratio = 23.43 +/− 15.84 mm, R-squared = 0.90 +/− 0.09, n=16), and failure tests (Ratio = 38.81 +/− 26.39 mm, R-squared = 0.77 +/− 0.20, n=16). No statistically significant differences were detected between the Torsion/Tension ratios (p=0.13) or between the linearity (R-squared) of the best-fit lines (p> 0.085). Conclusion: A strong linear relationship between applied torsion and resulting tensile forces for the ligament was exhibited during all testing phases. This may suggest that there is interplay between torsion and tension in both the stabilization of the scapholunate ligament during normal physiological motion and during resistance to injury processes. This is the first report in the literature of the coupling of torsion with tension for the scapholunate ligament

Aims. Diagnostic wrist arthroscopy is considered the gold standard for evaluating wrist joint complaints. Although this tool is often used to diagnose and stage scapholunate ligament (SLL) lesions, reports about the possible findings and their clinical relevance are scarce. Therefore, this study describes the patient characteristics, arthroscopic findings, and treatment of patients who underwent diagnostic arthroscopy for suspected SLL injury. Methods. We conducted a retrospective cohort study of patients who underwent diagnostic wrist arthroscopy due to suspicion of a SLL lesion based on medical history, physical examination, and imaging. We systematically gathered arthroscopic findings and complications. Results. This study included 324 patients, predominantly male (55%), with a median age of 44 years (IQR 29 to 54) and symptom duration of ten months (IQR 5 to 24). The indication of SLL injury was arthroscopically confirmed in 253 patients (78%). Isolated SLL injuries were found in 92 patients (28%) (Geissler I/II: 32%; III: 37%; IV: 32%). SLL lesions and SLL-associated cartilage damage were discovered in 31 patients (10%). Additional findings were found in 181 patients (56%), such as triangular fibrocartilage complex lesions (36%), lunotriquetral ligament lesions (7%), and radioscaphocapitate ligament lesions (11%). No pathology was found in 20 patients (6%). In 27 patients (8%), complications occurred due to wrist arthroscopy. The most common follow-up surgeries were 3LT (40%), salvage procedures (9%), and ulnar shortening osteotomy (6%). Conclusion. While diagnostic wrist arthroscopy commonly confirms the suspected SLL lesions and their severity, it often reveals additional pathologies (un)related to the suspected pathology. It is essential to perform the procedure thoroughly to establish all possible pathologies. Determining the appropriate treatment for these additional findings is not always straightforward and needs further investigation. Cite this article: Bone Jt Open 2025;6(3):312–320

Introduction: The current study investigates the influence of the interosseous portion of the scapholunate and the radioscaphocapitate ligaments in the range of movement of the scaphoid and lunate during flexion and extension of the wrist.

Material and Methods: 10 embalmed cadaveric specimens were studied. A jig was designed to clamp the forearms, holding the wrist in a fixed angle. Metal pointers with 1.5mm diameter were inserted into the scaphoid and the lunate. Digital cameras were aligned from the posterior and radial views and sequential photographs obtained during the full range of motion of the specimens. The SL and the RSC ligaments were then sectioned with new series of photographs obtained between each step. The angles in the photographs were measured with specific software.

Results: Sectioning the SL increased the angle between the lunate and the scaphoid by 12° on average, while sectioning the RSC increased the SL angle by a further 2 ° with the wrist in maximal flexion. With the wrist in extension the angle was also increased by 12° after division of the SL and a further 2° after section of the RSC.

Conclusions: Although volar and dorsal inuries may be associated, our study suggests that the SL has a much greater influence on the relative movement of the scaphoid and lunate than the RSC. The method also suggests that in a number of cases the variation in agulation may be small enough not to be detected as significant on x-rays.

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

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

The pattern of injury to the carpal ligaments following wrist trauma is unclear. Different imaging techniques often prove inconclusive rendering the diagnosis difficult and hence the treatment controversial. This study aimed to observe and evaluate the differences in scapholunate kinematics before and after sectioning the scapholunate interosseous ligament (SLIL) and radioscaphocapitate ligament (RSC). Twenty two embalmed cadaveric wrists were used. There were four males and seven females with an average age of 84 years. Their medical records confirmed the absence of previous history of wrist diseases or injuries. The extensor and flexors tendons of the wrist were removed leaving the capsule intact. Two drill bits (1.5 mm) were used to make a hole each in scaphoid and lunate, one centimeter apart. The drill bits were left in the bones to act as metal wires for calibration. Each wrist was moved through a set of motions and each movement was performed thrice; first one with the ligaments intact, second with SLIL sectioned and the last one with RSC excised. Digital photographs were taken and angles measured with MB Ruler software. Analysis of variance was done using SPSS 12. There was no angle between the metal pointers when the ligaments were intact. There was movement and change in angle detected when SLIL and RSC were sectioned. The sectioning of the SLIL lead to a significant increase in the angle between the pointers in all the movements recorded (p value < 0.001). Subsequent sectioning of the RSC further increased this angle but this increase was much smaller compared to that after sectioning SLIL. On completion of the measurements the wrist capsule was opened to reveal that both the ligaments had been successfully sectioned and there were no degenerative changes in the bones or ligaments in any wrist. This first cadaveric evaluation of alterations in scapholunate motion with sectioning of SLIL and RSC revealed that SLIL has a significant influence on the scapholunate kinematics, where as sectioning of the RSC has little additional effect. This in-vivo finding might have implications of importance of preserving SLIL during wrist surgeries and its role in management of carpal instabilities

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

The April 2012 Wrist & Hand Roundup. 360 . looks at releasing the trigger finger, function in the osteoarthritic hand, complex regional pain syndrome, arthroscopic ligamentoplasty for the injured scapholunate ligament, self-concept and upper limb deformities in children, wrist arthroscopy in children, internal or external fixation for the fractured distal radius, nerve grafting, splinting the PIPJ contracture, and finding the stalk of a dorsal wrist ganglion

In a randomised prospective study, 20 patients with intra-articular fractures of the distal radius underwent arthroscopically- and fluoroscopically-assisted reduction and external fixation plus percutaneous pinning. Another group of 20 patients with the same fracture characteristics underwent fluoroscopically-assisted reduction alone and external fixation plus percutaneous pinning. The patients were evaluated clinically and radiologically at follow-up of 24 months. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and modified Mayo wrist score were used at 3, 9, 12 and 24 months postoperatively. In the arthroscopically- and fluoroscopically-assisted group, triangular fibrocartilage complex tears were found in 12 patients (60%), complete or incomplete scapholunate ligament tears in nine (45%), and lunotriquetral ligament tears in four (20%). They were treated either arthroscopically or by open operation. Patients who underwent arthroscopically- and fluoroscopically-assisted treatment had significantly better supination, extension and flexion at all time points than those who had fluoroscopically-assisted surgery. The mean DASH scores were similar for both groups at 24 months, whereas the difference in the mean modified Mayo wrist scores remained statistically significant. Although the groups are small, it is clear that the addition of arthroscopy to the fluoroscopically-assisted treatment of intra-articular distal radius fractures improves the outcome. Better treatment of associated intra-articular injuries might also have been a reason for the improved outcome

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

We present an anatomical study and the description of a new surgical technique for the arthroscopic treatment of scapholunate ligament injuries. Materials and Methods: 5 specimens were used to perform the new arthroscopic technique and prove with confidence it’s reproducibility. After arthroscopic surgery, anatomic dissection had been performed to measure the distances to the critical wrist structures such as the posterior interosseous nerve, the radial artery and the distance of the portals to the extensor compartments. Surgical Technique: Ligamentoplasty was performed with the flexor carpi radialis to reconstruct the dorsal scapholunate ligament. First, a standard wrist arthroscopy was performed, and two bone tunnels were made. One across the scaphoid, through the 3/4 portal from its dorsal face to the tubercle, and another through the 4/5 portal to the lunate, perpendicular to its axis. The plasty of the FCR was obtained by a volar approach, and it was passed through the tunnel of the scaphoid. Subsequently, the plasty was passed from the 3/4 portal to 4/5, through a small 3-cm arthrotomy on this site. Finally, we introduced the plasty in the lunate tunnel with a biotenodesis screw. At this manner the tenodesis Bone (insertion of FRC) - Tendon (FRC) - Tenodesis (FRC in lunate) was completed. Results: Tenodesis were obtained in all 5 cases with no mayor damage to the structures described. The average of distance to IP nerve was 12 mm; to radial artery 17 mm and to superficial radial artery 9 mm. The average of distances from the portals to different extensor compartments are 3/4 portal to the second 2,8 mm, to the third 3,2 mm and to the forth 5,2 mm. 4/5 portal to the fourth 1,8 mm and to the fifth 7,2 mm. Radial midcarpal portal to the second 2mm and to the fourth 5,6 mm. Cubital midcarpal portal to the fourth 2,2 mm and to the fifth 7,4 mm. Discussion: This is a revolutionary wrist arthroscopic technique, because usual reconstruction techniques of the scapholunate damage are done openly. With this arthroscopic technique three objectives are achieved. First, it reduces soft tissue damage, scar tissue and the section of secondary stabilizers of the wrist. Secondly, it ensures that, without doing and arthrotomy, the injured of IP nerve is avoided maintaining proprioception of the wrist and the properly function of the dynamic stabilizers. And finally the use of a stronger implant will shorten the time of immobilization. Conclusion: We have developed a new surgical technique for arthroscopic reconstruction of the scapholunate ligament that will improve the outcomes of standard open techniques, as long as it will gain mobility and maintain the proprioception of the wrist. However clinical trials in patients are needed to confirm with scientific rigor the new technique described

Aim:. To assess the clinical outcomes of patients that had perilunate or lunate dislocations treated with either open or closed reduction and wiring without repair of the scapholunate interosseous ligament (SLIL). Background:. Current literature states that acute perilunate dislocations should be treated with open reduction and repair of the dorsal scapholunate ligament. This is to prevent dissociative carpal instability and potential long term degenerative arthrosis. Methods:. A retrospective review of patients who sustained a perilunate or lunate dislocation, with no associated radial or carpal fracture was conducted. All were treated by reduction and percutaneous wiring without repair of the SLIL. Patients were examined and data was collected regarding patient's pain, range of motion, grip strength, instability and return to work. All patients had a Mayo wrist score. Pre and post-surgical radiographs were assessed and the scapholunate distance, scapholunate angle and the radiolunate angle were measured. The presence of a high riding scaphoid and osteoarthritis was recorded. Results:. A total of 13 patients were included in the study, with an average follow up of 32 months. 92% of patients had no pain in their wrist at final follow up. Range of movement was 78% of the normal side. 70% of patients returned to work. 92% of patients had no clinical wrist instability. Grip strength was 82% of the opposite side. Radiographic assessment showed an average scapholunate distance of 2.6 mm, a scapholunate angle of 65° and radiolunate angle of 11°. One of the 13 patients had a high riding scaphoid. 23% of patients had arthritic changes of the carpus on plain radiographs. Of the 13 patients, 3 had excellent mayo scores, 4 good, and 6 fair. No patients had poor scores. Of the 13 patients reviewed 10 returned to work, those that did not were not able to due to other disabilities acquired at the time of their accident. Conclusion:. Acute management of perilunate dislocations with reduction and percutaneous wiring without repair of the SLIL, resulted in the majority of patients having a pain free, stable, mobile wrist with an above average Mayo wrist score and no arthritic change on radiographic assessment

The purposes of this study were to define the range of laxity of the interosseous ligaments in cadaveric wrists and to determine whether this correlated with age, the morphology of the lunate, the scapholunate (SL) gap or the SL angle. We evaluated 83 fresh-frozen cadaveric wrists and recorded the SL gap and SL angle. Standard arthroscopy of the wrist was then performed and the grades of laxity of the scapholunate interosseous ligament (SLIL) and the lunotriquetral interosseous ligament (LTIL) and the morphology of the lunate were recorded. Arthroscopic evaluation of the SLIL revealed four (5%) grade I specimens, 28 (34%) grade II, 40 (48%) grade III and 11 (13%) grade IV. Evaluation of the LTIL showed 17 (20%) grade I specimens, 40 (48%) grade II, 28 (30%) grade III and one (1%) grade IV. On both bivariate and multivariate analysis, the grade of both the SLIL and LTIL increased with age, but decreased with female gender. The grades of SLIL or LTIL did not correlate with the morphology of the lunate, the SL gap or the SL angle. The physiological range of laxity at the SL and lunotriquetral joints is wider than originally described. The intercarpal ligaments demonstrate an age-related progression of laxity of the SL and lunotriquetral joints. There is no correlation between the grades of laxity of the SLIL or LTIL and the morphology of the lunate, the SL gap or the SL grade. Based on our results, we believe that the Geissler classification has a role in describing intercarpal laxity, but if used alone it cannot adequately diagnose pathological instability. We suggest a modified classification with a mechanism that may distinguish physiological laxity from pathological instability

Complex carpal injuries can be difficult to assess and manage. They usually occur following high energy injuries to the wrist. Imaging in the form of traction views and a CT scan can help understand the detail of the fracture dislocation pattern. Perilunate dislocations and perilunate fracture dislocations are commonly managed with a dorsal approach to provide an anatomic reduction. A volar approach can be used is median nerve entrapment and allows a surgical repair of the volar aspect of the lunotriquetral ligament. Perilunate dislocations are often classified into greater and lesser arc injuries. The greater arc injuries include fractures which go through the radial styloid, scaphoid, capitate or triquetrum. Lesser arc injuries are through the scapholunate ligament and lunotriquetral ligament. It is common for there to be a combination of greater and lesser arc injuries. We have also identified a complex injury which is a lunate intra-arc injury. This is a fracture through the lunate. With this translunate perilunate dislocation it is important to stabilise the lunate prior to stabilising the remainder of the carpus. The authors have reviewed a series of complex injuries and developed a classification system based on the above findings. In complex cases where reconstruction is difficult then salvage procedures can be performed. SLAC wrist procedure, proximal row carpectomy and full wrist fusion can be performed particularly in highly comminuted cases or cases with a delayed presentation

The aim of the study was to compare the radiological findings of wrist arthrogram with wrist arthroscopy. This allowed us to establish the accuracy (sensitivity, specificity) of MRI arthrogram as a diagnostic tool. Thirty patients (20 female and 10 male) have undergone both wrist MRI arthrogram and wrist arthroscopy over the last 3 years at Macclesfield District General Hospital. The mean age at arthrogram was 42.4 years with an average 6.7 month gap between the two procedures. The MRI arthrogram was reported by a consultant radiologist with an interest in musculoskeletal imaging and the arthrosopies performed by two upper limb surgeons. Patients undergoing both procedures were identified. The arthrogram reports and operation notes were examined for correlation. Three main areas of pathology were consistently examined: TFCC (triangular fibrocartilage complex), scapholunate and lunatotriquetral ligament tears. The sensitivity and specificity of arthrogram was calculated for each. Other areas of pathology were also noted. In the case of TFCC tears MRI arthrogram had a 92.3% sensitivity and 54.6% specificity. The lunatotriquetral ligament examination with this technique was 100% sensitivity and specificity. However for scapholunate ligament tears it only had 50% sensitivity and 77.8% specificity. Wrist arthrogram and arthroscopy are both invasive techniques and equally time consuming. In cost terms the arthrogram remains cheaper but is superseded by arthroscopy as it is both diagnostic and therapeutic

Axial loading of the wrist results in carpal pronation, which loads the scapholunate ligament (SLL). ECRL and FCR are carpal supinators and ECU is a carpal pronator. In this study we aim to show differential activity in the ECRL and ECU as a protective mechanism for the SLL in simulated falls. Eight healthy volunteers were recruited for a simulated fall situation. Surface EMG was used to record muscle activity in the six major muscles that control wrist movement (FCU, FCR, ECRL, ECU, APL, ECRB) in the right forearm. The forearm skin was prepared in a standard fashion and the electrodes placed following an established protocol. Recordings were made using zero wire (Noraxon) surface EMG equipment. The data was exported and analysed using MyoResearch XP. Recordings were rectified and mean value, peak value, area under the curve and frequency were compared. Recordings were divided into five time periods from rest to post-impact. ECRL has the most predictable and consistent response to impact of the wrist on the ground. Immediately following impact there is inhibition of the extensors and no change in flexor activity. The next phase is characterised by a ‘spike’ in ECRL activity with a less marked increase in ECRB and minimal change in ECU activity. There is decrease activity in the flexors during the ECRL peak. The pre-peak period lasts between 5 to 10 ms. The ECRL peak period lasts between 20 to 30 ms. We have identified that ECRL is active post fall and this response takes less than 10 ms from the time of impact. The time response is in the order of a spinal proprioceptive reflex. We were unable to identify a stretch response in the flexors that could act to trigger the ECRL response

Aim. This study reviewed the efficacy of a CT arthrogram in clinical decision making for wrist disorders. Methods. Sixty four consecutive CT arthrograms done in a three year period at Glenfield Hospital were selected. All patients were referred by hand consultants at the Glenfield Hospital and all investigations were performed by a single senior musculoskeletal radiologist. CT arthrograms focussed on the following areas: scapholunate interosseous ligament (SLIL), lunotriquetral interosseous ligament (LTIL), peripheral and central triangular fibrocartilage complex (TFCC) tears, and articular surface disorders. Referral and clinic letters for all patients were obtained. We collected patient demographic detail, prescan diagnosis and clinical plan, CT arthrogram findings, postscan diagnosis and clinical plan and the final outcome. A decision was made whether the scan helped in the clinician's management plan and if so how it helped. Results. There were 35 male and 29 female patients with a mean age of 44.1 years. The right wrist was involved in 42 and the left in 22 patients. Sixty three of the 64 patients had their management based on the CT scan. In 54 of these the CT arthrogram either confirmed and calibrated the diagnosis or identified a new diagnosis. In 10 patients the scan was normal and allowed patient reassurance. Thirty six patients had ulnar sided problems, 20 had radial sided disorders and eight had midcarpal abnormality. The most common abnormality noted was a TFCC tear (24). The next most common was chondral damage/arthritis (14) followed by scapholunate interosseous ligament tear (12). The diagnosis was either confirmed and its extent established (31) or identified in addition to the primary diagnosis (19). Conclusions. The CT arthrogram is a helpful tool in the management of intra-articular wrist pathology. We found it to be useful in both confirming and calibrating the diagnosis and also diagnosing occult patho

Aim. To evaluate the correlation between the clinical Kirk Watson test and arthroscopic Geissler classification in scapholunate instability. Methods. All patients undergoing wrist arthroscopy between April 2006 and April 2010 were evaluated. Patients were included in the study if they had a Kirk Watson test and a wrist arthroscopy with an assessment of the stability of the scapholunate joint using the Geissler classification. Patients who had a Kirk Watson test performed with subsequent normal scapholunate joint at arthroscopy were included as a control group. Geissler grades 1 and 2 and grades 3 and 4 were grouped for further analysis into low and high grade instability groups respectively. Results. 76 patients were included in the study. 62 had scapholunate pathology and 14 had normal arthroscopic examinations of the stability of the joint. A positive test was found in 30% (3) of patients with grade 1 instability, 29% (4) with grade 2, 60% (12) with grade 3 and 78% (14) with grade 4 instability demonstrated at arthroscopy. The test was positive more commonly in those with grade IV instability compared with others (78% vs. 43%; p=0.015). There was a higher number with a negative test in the low grade instability group (71% vs. 32%; p=0.01) and a higher number with a positive test in the high grade instability group (68% vs. 29%; p=0.006). The test was most sensitive (78%) and most specific (57%) for those classified with Geissler grade IV instability and sensitivity and specificity were also high for those with high grade instability (68% and 66% respectively). Conclusions. The Kirk Watson test is a sensitive and specific test for diagnosis of higher grade instability of the scapholunate joint. We found a positive correlation between increasing scapholunate instability when assessed using the Geissler classification and positivity of the test. This confirms that the Kirk Watson test can be a useful test in the assessment of those with symptomatic instability of the joint and may reflect damage not only to the scapholunate ligament but to the secondary stabilisers of the joint as well