Conservative treatment of scaphoid fracture: Protocol for a systematic review

The scaphoid is the most commonly fractured carpal bone. Fractures affecting this bone affect young and active patients between 15 and 40 years of age. Stable scaphoid fractures are treated conservatively by plaster cast immobilization or other type of orthosis for an average period of four to 12 weeks. Failure to treat scaphoid fractures may result in avascular necrosis, nonunion, and early secondary osteoarthritis, which may result in significant economic and social impact due to the affected population, formed by young people of productive age. The management of this type of fracture varies significantly between different Institutions and orthopedic surgeons. This article describes a protocol for a systematic review that aims to evaluate the effects (benefits and harms) of conservative interventions in the treatment of scaphoid fractures in adults.

Radiographic Landmarks for Ideal Port Placement in Wrist Arthroscopy

Background The placement of wrist arthroscopy portals is traditionally performed using distances from anatomic landmarks. We sought to evaluate the safety of traditional portal placement and determine if radiographic landmarks could provide an additional method of identifying tendon intervals. Methods Six cadaveric specimens were used to evaluate the accuracy of portal placement based on anatomic and radiographic landmarks. Fluoroscopic images were used to document the location of previously described surface landmarks. Soft tissue was dissected away to identify the relationship between the transcutaneously placed portals and the extensor tendons. With soft tissue removed, tendon intervals were identified in relationship to anatomic carpal bone landmarks, and interval distances measured. Portals were then placed under radiographic imaging on the final three specimens and accuracy was examined by the removal of overlying soft tissue to confirm accurate interval placement Results The 3,4 portal was safely placed using only surface anatomic landmarks, however the 4,5 and midcarpal ulnar (MCU) portal sites were not consistently placed in the intended tendon interval, especially in larger wrists. Radiographic interval targets for the 3,4 portal were identified at the ulnar aspect of the scaphoid and the 4,5 portal at the ulnar one-third of the lunate. The radiographic site for the MCR was located at the inferior radial one-third of the capitate and the MCU portal was located at the radial aspect of the hamate. The 6R portal radiographic landmark is at the radial aspect of the triquetrum and 6U at the ulnar aspect of the triquetrum. Conclusion Portal placement in wrist arthroscopy based on anatomic landmarks alone can be unreliable in larger wrists. Radiographic imaging based on carpal bone landmarks provides an additional tool for consistent placement of portals in wrist arthroscopy and may limit unintended injury to extensor tendons. Level of Evidence This is a Level VI study.

Excessive Derotational K-Wire Angulation Decreases Compression by Headless Compression Screw

Background Scaphoid fracture is the most common carpal bone fracture. Open reduction internal fixation of scaphoid fractures typically undergo stabilization by a single headless compression screw (HCS). During screw insertion, a derotational Kirschner wire (K-wire) is often placed for rotational control of the near and far fragment. Questions/purposes The aim of this study was to determine if there is an angle of derotational K-wire placement in relation to the axis of a HCS that compromises the amount of compression generated at a fracture site by the HCS. We hypothesize that increased off-axis angle will lead to decreased compression across the fracture site. Methods A Cellular Block 20 rigid polyurethane foam (Sawbones, Vashon, WA) scaphoid model was created to eliminate variability in bone mineral density in cadaveric bone. MiniAcutrak HCS screws (Acumed, Hillsboro, OR) were used for testing. Three conditions were tested: (1) HCS with derotational wire inserted parallel to the HCS (zero degrees off-axis); (2) HCS with derotational wire inserted 10 degrees off-axis; and (3) HCS with derotational wire inserted 20 degrees off-axis. Results A statistically significant difference in the mean compression of the control group (56.9 N) was found between the mean compression with the derotational K-wire placed 20 degrees off-axis (15.2 N) (p = 0.001). Conclusions Compression at the fracture site could be impeded by placing an excessively angulated off-axis derotation wire prior to insertion of the HCS. Clinical Relevance Our study adds a new detail to the optimal technique of HCS placement in scaphoid fractures to improve compression and fracture union.

Kinematic Analysis During Straight Line Free Swimming in Horses: Part 1 - Forelimbs

Background: Swimming is used for rehabilitation and conditioning purposes in equine sports medicine despite the lack of understanding of equine swimming kinematics. The aim of this study was to assess forelimb joints kinematics (elbow, carpus, and fetlock) in swimming horses. The specific objectives were 1- to calculate and compare joint angles in swimming vs. passive mobilizations (PM), 2- to determine joint angular velocities during a swimming stride cycle.Methods: Eleven elite endurance horses swam in a 100-m straight pool. Underwater (swimming) and overground (PM) videos were recorded from the horses' left side. Joint markers were applied on the lateral hoof wall, lateral metacarpal epicondyle, ulnar carpal bone, lateral humeral epicondyle, and the greater tubercle of humerus, from which elbow, carpus and fetlock angles, and angular velocities were obtained. As a reference, maximal fetlock, carpus, and elbow flexion/extension angles were determined during PM overground. Differences between angle extrema, angular velocities and range of motion (ROM) were compared.Results: Carpus and fetlock ROM were significantly smaller (p < 0.001) during swimming when compared with PM, while there was no difference in elbow ROM between both situations. The carpus had the greatest ROM of all joints during swimming. Absolute angular velocities values of all joints during swimming were greater during retraction than protraction (p < 0.001). When compared to other joints during protraction, the carpus joint reached the highest angular velocity.Conclusion: Swimming, as a rehabilitation exercise, has the potential to benefit horses where great elbow ROM with a moderate carpus and fetlock extension are wanted.

Compression Screw Fixation of Lunate Fracture: Case Report and Review of the Literature

Background Isolated traumatic lunate fractures without other surgical carpal bone or ligamentous injuries are extremely rare, with few published reports available to guide management. Lunate fracture management is controversial, and depends on concurrent injuries of adjacent carpal bones, ligaments, risk of ischemia, and displacement. Case Description A 48-year-old right hand dominant man suffered a crush injury to the left hand caught between a forklift and a metal shelf. Radiographs and computed tomography imaging of the left hand and wrist were significant for a displaced Teisen IV fracture of the lunate. A dorsal ligament sparing approach was utilized to access, reduce, and fixate the fracture using a headless compression screw. After immobilization and rehab, at 9 months after initial injury, the patient was back to work on full duty without restriction and pleased with the results of his treatment. Literature Review A literature review of lunate fracture compression screw fixation was performed and revealed a total of three reports indicating successful treatment of fractures, with patients returning to full activity. Clinical Relevance Lunate fractures are rare, often missed, and treating these injuries can be challenging, particularly in the setting of acute trauma. Based on our limited experience, we believe that open reduction and internal fixation of isolated Teisen IV lunate fractures with a headless compression screw is a viable treatment modality with satisfactory outcomes.

Unilateral congenital lunate absence: A case report

Isolated congenital aplasia of carpal bones in the absence of an associated congenital syndrome is exceedingly rare. Since the first documented case report of congenital carpal bone absence in 1911, only 12 additional case reports have been published. Here we present a case report of an otherwise healthy 43-year-old male with unilateral congenital absence of the lunate, which has only been previously reported once in the literature.