The natural history of scapholunate ligament injury is unknown. In fact, as far as we can tell, there has been no study examining the long-term natural history of this condition. It has, however, been assumed that the long-term progression of this injury leads to secondary osteoarthritis – scapholunate advanced collapse (the so-called SLAC wrist). In this study, we evaluated the clinical condition of 11 patients with proven scapholunate ligament injuries that had declined further treatment in an attempt to quantify any long-term disability. Whilst there was on-going pain and functional limitation in the injured wrist, there was no rapid progression of the osteoarthritis or SLAC wrist deformity

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 August 2015 Wrist & Hand Roundup360 looks at: Scaphoid screws out?; Stiff fingers under the spotlight; Trigger finger: is complexity needed?; Do we really need to replace the base of the thumb?; Scapholunate ligament injuries and their treatment: a missed research opportunity?; Proximal row carpectomy versus four-corner arthrodesis

This study describes the introduction of a virtual pathway for the management of suspected scaphoid fractures and reports patient-reported outcome measures (PROMs) and satisfaction following treatment with this service. All adult patients that presented with a clinically suspected scaphoid fracture that was not visible on presentation radiographs over a one-year period were eligible for inclusion in the pathway. Demographics, examination findings, clinical scaphoid score (CSS) and standard four view radiographs were collected at presentation. All radiographs were reviewed virtually by a single consultant hand surgeon, with patient-initiated follow-up on request. PROMs were assessed at a minimum of one year post presentation and included the QuickDASH, EQ-5D-5L, the Net Promoter Score (NPS) and return to work. There were 221 patients referred to the virtual pathway. The mean age was 41 (range 16–87; SD 18.4 years) and there were 99 men (45%). There were 189 (86%) patients discharged with advice and 19 (9%) patients were recalled for clinical review (seven undisplaced scaphoid fractures, six other acute fractures of the hand or wrist, two scapholunate ligament injuries, and four cases where no abnormality was detected). Thirteen patients (6%) initiated follow-up with the hand service; no fracture or ligament injury was identified within this group. PROMs were available for 179 (81%) patients at a mean of 19 months follow-up (range: 13 – 33 months). The median QuickDASH score was 2.3 (IQR, 0–15.9), the median EQ-5D-5L was 0.85 (IQR, 0.73–1.00), the NPS was 76, and 173 (97%) patients were satisfied with their treatment. There were no documented cases of symptomatic non-union one year following injury. This study reports the introduction of a virtual pathway for suspected scaphoid fractures, demonstrating high levels of patient satisfaction, excellent PROMs, and no detrimental effects in the vast majority of cases

Wrist motion is achieved primarily via rotation at the radiocarpal and midcarpal joints. The contribution of each carpal bone to total range of motion has been previously investigated, although there is no consensus regarding the influence of each structure to global wrist motion. The objective of this comprehensive in-vitro biomechanical study was to determine the kinematics of the capitate, scaphoid and lunate during unconstrained simulated wrist flexion-extension. In addition, this study examined the effect of motion direction (i.e. flexion or extension) on the kinematics and contribution of the carpal bones. Seven fresh frozen cadaveric upper limb specimens (age: 67±18 yrs) were amputated mid-humerus, and the wrist flexors/extensors were exposed and sutured at their musculotendinous junctions. Each specimen was mounted on a wrist motion simulator in neutral forearm rotation with the elbow at 90° flexion. Passive flexion and extension motion of the wrist was simulated by moving a K-wire, inserted into the third metacarpal, through the flexion/extension motion arc at a speed of ∼5 mm/sec under muscle tone loads of 10N. Carpal kinematics were captured using optical tracking of bone fixated markers. Kinematic data was analysed from ±35° flexion/extension. Scaphoid and lunate motion differed between wrist flexion and extension, but correlated linearly (R‸2=0.99,0.97) with capitate motion. In wrist extension, the scaphoid (p=0.03) and lunate (p=0.01) extended 83±19% & 37±18% respectively relative to the capitate. In wrist flexion, the scaphoid (p=1.0) and lunate (p=0.01) flexed 95±20% and 70±12% respectively relative to the capitate. The ratio of carpal rotation to global wrist rotation decreased as the wrist moved from flexion to extension. The lunate rotates on average 46±25% less than the capitate and 35±31% less than the scaphoid during global wrist motion (p=0.01). The scaphoid rotates on average 11±19% less than the capitate during wrist flexion and extension (p=0.07). There was no difference in the contribution of carpal bone motion to global wrist motion during flexion (p=0.26) or extension (p=0.78). The capitate, lunate and scaphoid move synergistically throughout planar motions of the wrist. Our study found that both the scaphoid and lunate contributed at a greater degree during wrist flexion compared to extension, suggesting that the radiocarpal joint plays a more critical role in wrist flexion. Our results agree with previous studies demonstrating that the scaphoid and lunate do not contribute equally to wrist motion and do not function as a single unit during planar wrist motion. The large magnitude of differential rotation observed between the scaphoid and lunate may be responsible for the high incidence of scapholunate ligament injuries relative to other intercarpal ligaments. An understanding of normal carpal kinematics may assist in developing more durable wrist arthroplasty designs

Wrist motion is achieved primarily via rotation at the radiocarpal and midcarpal joints. The contribution of each carpal bone to total range of motion has been previously investigated, although there is no consensus regarding the influence of each structure to global wrist motion. The objective of this comprehensive in-vitro biomechanical study was to determine the kinematics of the capitate, scaphoid and lunate during unconstrained simulated wrist flexion-extension. In addition, this study examined the effect of motion direction (i.e. flexion or extension) on the kinematics and contribution of the carpal bones. Seven fresh frozen cadaveric upper limb specimens (age: 67±18 yrs) were amputated mid-humerus, and the wrist flexors/extensors were exposed and sutured at their musculotendinous junctions. Each specimen was mounted on a wrist motion simulator in neutral forearm rotation with the elbow at 90° flexion. Passive flexion and extension motion of the wrist was simulated by moving a K-wire, inserted into the third metacarpal, through the flexion/extension motion arc at a speed of ∼5 mm/sec under muscle tone loads of 10N. Carpal kinematics were captured using optical tracking of bone fixated markers. Kinematic data was analysed from ±35° flexion/extension. Scaphoid and lunate motion differed between wrist flexion and extension, but correlated linearly (R^2=0.99,0.97) with capitate motion. In wrist extension, the scaphoid (p=0.03) and lunate (p=0.01) extended 83±19% & 37±18% respectively relative to the capitate. In wrist flexion, the scaphoid (p=1.0) and lunate (p=0.01) flexed 95±20% and 70±12% respectively relative to the capitate. The ratio of carpal rotation to global wrist rotation decreased as the wrist moved from flexion to extension. The lunate rotates on average 46±25% less than the capitate and 35±31% less than the scaphoid during global wrist motion (p=0.01). The scaphoid rotates on average 11±19% less than the capitate during wrist flexion and extension (p=0.07). There was no difference in the contribution of carpal bone motion to global wrist motion during flexion (p=0.26) or extension (p=0.78). The capitate, lunate and scaphoid move synergistically throughout planar motions of the wrist. Our study found that both the scaphoid and lunate contributed at a greater degree during wrist flexion compared to extension, suggesting that the radiocarpal joint plays a more critical role in wrist flexion. Our results agree with previous studies demonstrating that the scaphoid and lunate do not contribute equally to wrist motion and do not function as a single unit during planar wrist motion. The large magnitude of differential rotation observed between the scaphoid and lunate may be responsible for the high incidence of scapholunate ligament injuries relative to other intercarpal ligaments. An understanding of normal carpal kinematics may assist in developing more durable wrist arthroplasty designs

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

The treatment of scapholunate (SL) ligament injuries is addressed by surgical procedures to stabilize the carpal joint. Open techniques include bone-ligament-bone transfers, tenodesis, partial fusions and carpectomies. Innovative procedures using wrist arthroscopy, offer minimally invasive fixation without full exposure of carpal bones; however, the success of the technique and its impact on the reduction on the range of carpal movement is as yet not well known. In this work, the performance of Corella tenodesis technique to repair the SL ligament is evaluated for a wrist type II by numerical methods. Human wrist can be classified based on the lunate morphology: type I for lunate that articulates with radius, scaphoid, capitate and triquetrum, and type II which has an extra surface to articulate with the hamate. A finite element model was constructed from CT-scan images, the model includes cortical and trabecular bones, articular cartilage and ligaments. Three scenarios were simulated representing healthy wrist, SL ligament sectioning and the Corella technique. The performance of the technique was assessed by measure the SL gap in dorsal and volar side as well as the SL angle to be compared to cadaveric studies. In intact position, the SL gap and the SL angle predicted by the numerical model is 2.8 mm and 44.8º, these values are consistent to the standard values reported in cadaveric experiments (2.0 ± 0.8 mm for SL gap and 45.8 ± 9.7 for SL angle). Virtual surgeries may help to understand and evaluate the performance of the techniques at clinical application

Aims

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

The December 2013 Wrist & Hand Roundup³⁶⁰ looks at: Scapholunate instability; three-ligament tenodesis; Pronator quadratus; Proximal row carpectomy; FPL dysfunction after volar plate fixation; Locating the thenar branch of the median nerve; Metallosis CMCJ arthroplasties; and timing of flap reconstruction