Ulnar Column Research Articles

Assessing the Need for Imaging after Distal Radius Fracture Fixation

Abstract Background Distal radius fractures are extremely common. Patients routinely undergo early imaging (around 2 weeks) after open reduction and internal fixation (ORIF) of distal radius fractures despite no clinical concerns. We analyzed the need for these radiographs by evaluating when imaging identifies complications after surgery. Methods All distal radius fractures treated with ORIF via a volar approach by the senior surgeon were included. Intraoperative and postoperative images were analyzed for maintenance of reduction and complications. Demographic data, fracture characteristics, and postoperative complications were also recorded. Results A total of 342 patients were identified. Postoperative images were obtained from 0 to 14, 15 to 90, 91 to 180, 181 to 365, or greater than 365 days after surgery. Some patients had multiple images. Measurements on postoperative images were statistically equivalent across all time points. Complications mostly occurred >90 days after surgery. Of the 26 patients with complications, 5 had a failure of reduction or plating seen on postoperative imaging. Two occurred after unrelated trauma; only three patients had unanticipated complications caught on routine imaging within 3 months after surgery. These patients had extraordinarily complex fractures in poor bone stock. Conclusion Early postoperative imaging is not necessary after ORIF for distal radius fractures unless the patient is elderly, or the fracture is severely comminuted with ulnar column or die-punch components. Thus, we suggest that patients have imaging only in the 3- to 6-month period to determine if the union has been achieved, which could provide cost savings to both surgeon and patient.

Degenerative changes of the wrist in mixed martial arts and boxing based on the three column theory

ABSTRACT Objective Mixed Martial Arts (MMA) is a relatively young combat sport. In contrast to classic boxing, MMA combines techniques of grappling and striking. However, characteristic long-term effects of MMA on the wrist are discussed controversially. Aim of this study was to elucidate characteristic degenerative changes of the wrist from MMA fighters in comparison to classic boxers. Methods In this study, eleven professional MMA fighters and ten professional boxers with chronic wrist pain were examined and compared. Age, weight, number of fights and weekly hours of training were recorded. Wrist and hand of each fighter were examined using a 3T-MR scanner. Degenerations of the radial, central and ulnar column were analyzed according to Navarro’s three-column theory and degenerative changes were categorized based on the classification of Fredericson. Results There was no significant difference of age, weight and number of fights between MMA fighters and boxers (p > 0.15). However, MMA fighters practiced significantly more hours per week (19.5 (MMA) vs. 8.5 (boxing) hours/week, p < 0.001). No significant associations were found between different training times per Week in terms of degenerative changes of the wrist in MMA and boxing based on the three column theory. The comparison of degenerative changes in the columns between MMA and boxing showed no significant differences. The MRI showed a significantly higher degeneration in the radial column compared to the central column among MMA fighters for ligaments (p = 0.01) and bones (p = 0.03). Conclusion Due to different fighting techniques, different physical traumas, including falls, pattern of degenerations of the wrist between MMA fighters and boxers are different. MMA fighters suffer of a highly degenerative radial column and boxers suffer of a homogeneous degeneration of all three columns.

The factors affecting the redisplacement in distal radius fractures

Objectives: Many instability criteria have been described in the literature to predict loss of reduction in distal radius fractures. However, the effect of the column location of the fracture on loss of reduction has not been investigated. The aim of this study is to investigate the effect of fracture column location and other radiological parameters on the loss of reduction of the distal radius fractures. Methods: A total of 106 patients who were treated conservatively for displaced distal radius fractures were included in the study. The average age of the patients included in the study is 54.9 years (range: 18-91 years). Anteroposterior and lateral radiographs of the wrist were taken in each patient at the time of first admission, immediately after reduction and casting, and at the 1st, 2nd and 6th weeks. Intraarticular fracture were evaluated by computed tomography (CT). Radial length, volar tilt angle and column location of the fracture were obtained by evaluating the radiographs and CT. The effects of post-reduction radiological parameters and column location of the fracture on loss of reduction were analyzed. Results: Reduction loss was detected in 23 (21.7%) of 106 patients. Metaphyseal fracture in 83 (78.3%) patients, intermediate volar column fracture in 76 (71.7%) patients, intermediate dorsal column fracture in 86 (81.1%) patients, ulnar column fracture in 52 (49.1%) patients and radial column fracture in 25 (23.6%) patients were determined. It was observed that having a fracture in the ulnar column or radial column caused a significant loss in radial length (p &amp;lt; 0.05). Metaphyseal and the intermediate column fractures did not make a statistically significant difference in reduction loss. Conclusions: Column location of the fracture can also be used to predict loss of reduction in the conservative treatment of distal radius fractures.

Column-Specific Distal Radius Fracture Fixation

Despite the popularity and success of volar fixed angle plating, variations in distal radius fracture presentation underscore the importance of understanding different surgical treatment options to maximize patient outcomes. The 3-column theory of wrist mechanics provided the foundation for using a column-specific fixation approach. Implant placement within the ulnar column can be challenging because of anatomical constraints. Some have described "safe zones" for implant position to decrease the potential for tendon impingement. A thorough understanding of the surrounding anatomy can allow fixation decisions based on fracture fragment location. Literature reports have shown excellent results when using fragment specific fixation constructs and similar outcomes when comparing these constructs with volar locked plating. Achieving optimal outcomes in surgically treated distal radius fractures requires the surgeon to be competent along a spectrum of surgical approaches and fixation constructs.

CT Based Characterization of Volar Surface of Distal Radius: Can an Ideal Volar Plate for Fixation of Distal Radial Fractures be Designed?

Background: Literature has limited evidence concerning the morphology of volar surface of distal radius. A mismatch between the plate-contour and contour of the actual volar bony surface can result in malreduction. The purpose of this study is to analyze the normal curvature morphology of volar surface of distal radius and related parameters that can help in designing of the volar plates for fixation of distal radial fractures. Methods: We retrospectively analyzed CT scans of uninjured healthy distal radii performed during a one year period (2018-2019). The mediolateral extent of the pronator quadratus line, the mediolateral curve of the pronator quadratus line, the mediolateral surface angle between intermediate column and radial column of distal radius, the curvatures and locations of their vertices for radial and intermediate columns were measured. Results: A total of 84 CT-based studies were analyzed. The mediolateral extent of the pronator quadratus line, the mediolateral curve of the pronator quadratus line, and the mediolateral surface angle between intermediate column and radial column of the distal radius were 24.27 mm, 144.8 degrees and 163.1 degrees, respectively. The mean volar curvatures of the radial and intermediate columns were 156.5 and 151.4 degrees, respectively and distances of their vertices from the pronator-quadratus line were 10.96 mm and 14.13 mm, respectively. Conclusions: Considerable variations occur in curvature morphology of distal radial volar surface. A best fit rather than an anatomical fit can be considered during implant selection owing to these variations. Besides volar curvature of radial and ulnar columns, location of their vertices, mediolateral angulation and surface curvature between these columns at the level of watershed line should also be considered in plate selection. A combination of a few serial increments of the described parameters in the designs of volar fixation plates would be helpful for surgeons in the best implant selection.

Surgical Management of Intra-articular Fracture Distal Radius by Multi axial Locked Plate

Background: Early wrist motion and adequate reduction and fixation of fracture fragments including radial styloid process achieved with volar multi axial locked plate have the advantage of minimizing the risk of joint stiffness and radio carpal joint incongruity present in other treatment modalities of distal radius fractures. The aim of this work was evaluation of surgical management of intra-articular fractures of distal end of radius with volar multi axial locked plate. Objective: To compare the radiological and clinical outcomes with volar multi-axial locked plate and other treatment modalities of multi-fragmentary and intra-articular distal radius fractures Patients and methods: This was a prospective study on 20 patients with intra-articular distal radius fractures operated with open reduction and internal fixation with volar multi axial locked plates from February 2018 to March 2020 via trans flexor carpi radialis tendon sheath (modified Henry approach) in 12 patients with radial column involvement, and ulnar (extensile carpal tunnel release approach) in 8 patients with ulnar column involvement. Follow up was carried out for six months. Results: The mean DASH score at 3rd month was 20.5 ± 6.9, while the mean DASH score at 6th month was 7.25 ± 4.1. The mean 3 months Modified MAYO Wrist Score was 81 ± 9.8 (median = 85), while the mean 6 months MMWS was 85.8 ± 12.5 (median = 90) which indicated a good ability of the patient to perform daily activities with minimal difficulty. At six months follow up 12 patients had excellent results, 6 patients had good results, one patient had fair result, and one patient had poor result. Conclusion: Multi axial locked plate has the advantage of purchasing small fracture fragments including radial styloid process, and also allowing for early range of motion exercises which prevent the occurrence of radio carpal joint arthritis or stiffness.

Association of scapholunate dissociation and two-part articular fractures of the distal radius.

Scapholunate dissociation may occur in association with distal radial fractures and is easily missed at initial presentation. The aim of this study was to examine variances in the scapholunate distance with respect to subtypes of two-part partial articular distal radial fractures. Axial computed tomography (CT) scans of acute two-part intra-articular radial fractures were assessed retrospectively from 80 patients and compared to 20 controls. From each scan, two images were analysed to identify the scaphoid, lunate and articular fracture line in the distal radius for fracture type categorization. The images were overlaid on a standardized distal radius template and the scapholunate distance measured. Significant increase in the scapholunate distance was noted in fracture subtypes: radial styloid oblique; dorsal ulnar column; sagittal ulnar column; and volar coronal. We conclude that these findings support the need for a higher index of suspicion for scapholunate dissociation in these distal radial fracture subtypes. Level of evidence: III.

Biomechanical evaluation of a transcondylar screw from the dorsolateral plate support on the stabilization of orthogonal plate configuration in distal humeral fracture

IntroductionIntra-articular distal humeral fractures involving both columns require double-plate fixation. In orthogonal plate fixation, screws from the medial plate reach the radial column, while screws from the dorsolateral plate run posterior–anterior, not creating interdigitation. The Synthes LCP-DHP system has an orthogonal plate configuration that enables dorsolateral plating with support, as the radial and ulnar columns are linked via interdigitation of the distal screws. We hypothesized that the transcondylar screw from the posterolateral plate, which interdigitates with screws from the medial plate, enables more rigid stabilization of orthogonal plating in distal humeral AO type C fractures. MethodsA previous study reported the biomechanical properties of orthogonal plate fixation using an AO type 13-C2.3 intra-articular fracture model with a 1-cm supracondylar gap using artificial bones (Kudo et al., Injury, 2016). We performed a biomechanical study of the dorsolateral plate with support, and inserted one 2.7-mm locking screw through the support in the lateral-to-medial direction, creating interdigitation of the distal screws. A 0–200 N axial load was applied separately to the radial and ulnar columns. We calculated the stiffness of both columns, and the anterior displacement of the condylar fragment. We compared the biomechanical properties of orthogonal plating with versus without interdigitation. ResultsThere were no significant differences between the two groups in radial or ulnar axial compression. The ulnar column was stiffer than the radial column in both groups. There were no significant differences between groups in the angular displacements of the capitellum or trochlea. The capitellum moved more anteriorly than the trochlea during axial compression in both groups. DiscussionThe radial and ulnar columns were linked via interdigitation of the distal screws by adding one transcondylar screw from the dorsolateral plate, which did not affect radial column stiffness or capitellar anterior movement under axial compression. In the orthogonal configuration, axial compression induced more anterior displacement of the capitellum than the trochlea, which may induce secondary fragment or screw dislocation on the dorsolateral plate or nonunion at the supracondylar level. ConclusionsThe transcondylar screw from the dorsolateral plate did not affect axial compression of the radial column or capitellar anterior displacement.

Palmer Midcarpal Instability: An Algorithm of Diagnosis and Surgical Management

Background Palmar midcarpal instability (PMCI) is an uncommon form of nondissociative carpal instability. However, it is an important cause of chronic ulnar wrist pain. Diagnosis can be difficult and high index of suspicion is mandatory. Pathomechanics and optimal treatment of PMCI remain uncertain. We propose an algorithm of clinical diagnosis and evaluate the outcome of our management. Materials and Methods Between 2000 and 2011, 16 patients, including 7 males and 9 females, of a mean age of 33.9 diagnosed with PMCI were reviewed for their clinical, radiologic, and arthroscopic features. All patients presented with ulnar wrist pain in their dominant hands except in one. Initial management included a disease-specific anticarpal supination splint. Refractory cases were evaluated by arthroscopy and treated by arthroscopic thermal shrinkage using radiofrequency appliance as an interim or definite surgical intervention. Shrinkage was targeted at the ulnocarpal ligament at the radiocarpal joint and triquetrohamate ligament at the midcarpal joint. Nonresponsive or recurrent cases were managed by a novel technique of dorsal radiocarpal ligament reconstruction procedure using a pisiform-based split flexor carpi ulnaris (FCU) tendon graft. Results In all cases, the midcarpal clunk test was positive with pain. Other common clinical features included lax ulnar column, carpal supination, volar sagging of the wrist, increased pisostyloid distance, wrist pain aggravated by passive hand supination and not by passive forearm supination, and increased wrist pain upon resisted pronation, which could be partially alleviated by manually supporting the pisostyloid interval. Common arthroscopic findings were excessive joint space at triquetrohamate interval and reactive synovitis over the ulnar compartments. Nine patients (56.3%) responded well to splinting alone at an average follow-up of 3.3 years. Arthroscopic thermal shrinkage was performed in five patients with recurrence in two patients. Five patients received split FCU tendon graft for ligament reconstruction. All patients showed improvement in the wrist performance score (preop 21.0, postop 36.6 out of 40) and pain score (preop 10.0, postop 2.2 out of 20) at the final follow-up of average 86 months (range: 19-155 months). Grip strength improved from 66.9 to 82.0% of the contralateral side. Wrist motion slightly decreased from a flexion/extension arc of 132 to 125 degrees. Three patients were totally pain free, one had mild pain, and one had moderate fluctuating pain. All patients returned to their original works. X-ray showed no arthrosis. Conclusion PMCI is an uncommon but significant cause of chronic ulnar wrist pain. We have developed a clinical algorithm for diagnosis of the condition. The natural history seems to favor a benign course. Conservative treatment with an anticarpal supination splint is recommended as the initial management. Surgical options for resistant cases include arthroscopic thermal shrinkage or soft tissue reconstruction. The reconstruction of the dorsal radiocarpal ligament using a pisiform-based split FCU tendon graft provides reliable restoration of the carpal stability with good long-term outcome and few complications. This should be considered a viable alternative to limited carpal fusion.

Reduced Risk of FPL-Tendon Rupture in Distal Radius Fracture Treated by a Palmar V-Shaped Plate

Objectives: Palmar locking plates enabling early active motion are successfully used in distal radius fracture treatment. But some fracture types can necessitate to place a plate distally to the watershed line with the risk of rupture of the flexor pollicis longus (FPL) tendon. In addition, the indication for implant removal following palmar plating is still discussed controversially. Patients and Method: In this prospective follow-up study, 18 patients with distal radial fracture (DRF) were stabilized by a new anatomical designed V-shaped palmar plate (Medartis, Basel, Switzerland). Radial inclination (RI), dorsal tilt (DT), and ulnar variance (UV) were assessed. An independent radiologist investigated the FPL tendon by ultrasound to course within the V-space of the plate at its distal end. In addition, the gliding and course of the FPL tendon was investigated during surgery. Results: In lateral projection, the plate appeared Soong type 0 (n = 3), Soong type 1 (n = 12), and Soong type 2 (n = 3). RI measured 20° (minimum 14°, maximum 27°), DT 3.8° (minimum 0°, maximum 12°), and UV 0 mm (minimum −3, maximum 2). In sonography, the FPL tendon run within the V-space in all cases. In all Soong types, there was no contact of the FPL tendon with the plate found in ultrasound. In Soong type 2, the ulnar column of the plate protruded and caused friction of the flexor digitorum profundus (FDP) tendon in 2 patients when a fit bone/implant contact was missing. Protrusion was seen in dorsal displacement of the distal fragment ad latus and soft tissue interposition. Intraoperatively, the radial column of the plate ended proximal at the watershed line without contact to the FPL tendon. Proximal to the watershed line, the course of the FPL tendon was minimally altered after release of the pronator quadratus (PQ) and mobilizing the FPL muscle for plate positioning. It remained unaltered distal to the watershed line where the FPL tendon enters the nonreleased carpal tunnel. Conclusion: The V-shaped FPL plate spared the FPL tendon in all Soong-type plate positions. Achieved reduction of RI greater 14°, DT more than 0°, and UV better than −3 mm proofed sufficient for the V-space design to avoid friction of the FPL. Restoration of DT and firm bone/plate contact of the distal fragment are important in distal plate position. Implant removal of plates positioned Soong types 1 and 2 seems to be no more imperative. In Soong type 3, the FDP tendons should be considered to be of some risk.

Biomechanical properties of orthogonal plate configuration versus parallel plate configuration using the same locking plate system for intra-articular distal humeral fractures under radial or ulnar column axial load

IntroductionPrevious reports have questioned whether an orthogonal or parallel configuration is superior for distal humeral articular fractures. In previous clinical and biomechanical studies, implant failure of the posterolateral plate has been reported with orthogonal configurations; however, the reason for screw loosening in the posterolateral plate is unclear. The purpose of this study was to evaluate biomechanical properties and to clarify the causes of posterolateral plate loosening using a humeral fracture model under axial compression on the radial or ulnar column separately. And we changed only the plate set up: parallel or orthogonal. Materials and methodsWe used artificial bone to create an Association for the Study of Internal Fixation type 13-C2.3 intra-articular fracture model with a 1-cm supracondylar gap. We used an anatomically-preshaped distal humerus locking compression plate system (Synthes GmbH, Solothurn, Switzerland). Although this is originally an orthogonal plate system, we designed a mediolateral parallel configuration to use the contralateral medial plate instead of the posterolateral plate in the system. We calculated the stiffness of the radial and ulnar columns and anterior movement of the condylar fragment in the lateral view. ResultsThe parallel configuration was superior to the orthogonal configuration regarding the stiffness of the radial column axial compression. There were significant differences between the two configurations regarding anterior movement of the capitellum during axial loading of the radial column. DiscussionThe posterolateral plate tended to bend anteriorly under axial compression compared with the medial or lateral plate. We believe that in the orthogonal configuration axial compression induced more anterior displacement of the capitellum than the trochlea, which eventually induced secondary fragment or screw dislocation on the posterolateral plate, or nonunion at the supracondylar level. In the parallel configuration, anterior movement of the capitellum or trochlea was restricted because of the angular stability of the plate and locking screws in the condyle. ConclusionsThe posterolateral plate tended to bend anteriorly under axial compression of the radial column in the orthogonal configuration, which led to secondary displacement of the posterolateral plate and eventual screw loosening.

Influence of Gap Shape on Biomechanical Properties of Extra-Articular Distal Humeral Fracture - A Finite Element Study

The aim of the study was to assess the influence of gap shape on biomechanical results in extra-articular distal humeral fracture: with contact on the posterior part (by anterior gap) and contact on ulnar column (by radial gap). The goal was to examine if and to what extent did displacements decrease in comparison with previously examined parallel gap without bony contact. The finite element analysis on the three different plate constructs was performed, i.e. parallel, perpendicular and newly designed Y shape plate were considered. Displacements were measured on articular surface and gap point. The most visible decrease of maximum displacements in the distal part of the model was detected in the Y plate model with axial loading: in case of anterior gap 58.5% and especially at radially formed gap 60.9%. Similarly, at axial loading, displacement at the analyzed point on fracture gap most significantly decreased in Y plate model (by 49.4%) at posterior bony contact. Moreover, the latter showed displacement decrease by 68.5% at ulnar bone contact. Furthermore, if a longer radial plate than the ulnar one was used, varus stress could have been avoided. Study results suggested that sufficient stability could be ensured with the newly designed Y shape plate.

Palmar mid-carpal instability: My management algorithm

Introduction Palmar mid-carpal instability (PMCI) is an uncommon form of non-dissociative carpal instability, seldom reported in Asian population. It is however an important cause of chronic ulnar wrist pain. Diagnosis can be difficult and high index of suspicion is mandatory. Pathomechanics and optimal treatment of PMCI remains uncertain worldwide. We analyze our unique diagnostic approach in Chinese patients for the proposed etiology and evaluate our management outcomes. Methods Between 1997 and 2010, 16 patients diagnosed PMCI were reviewed for their clinical, radiologic and arthroscopic features. All patients were initially managed conservatively with a disease specific anti-carpal supination splint; refractory cases were evaluated by arthroscopy and treated by arthroscopic thermal shrinkage using radio-frequency appliance as an interim or definite surgical intervention. Shrinkage was targeted at the ulnocarpal ligament at the radiocarpal joint and triquetro-hamate ligament at the mid-carpal joint. Shrinkage of dorsal radiocarpal ligament was not attempted to minimize potential complication. Non-responsive or recurrent cases were managed by a newly designed dorsal radio-carpal ligament reconstruction procedure using a pisiform-based split flexor carpi ulnaris (FCU) tendon graft. Clinical outcomes were evaluated at an average of 86 months. Results Seven male and 9 female patients of a mean age 33.9 were diagnosed PMCI. All except one presented with ulnar wrist pain in their dominant hands. The average duration of symptom was 14 months. Most patients reported minor wrist injury before development of symptoms. Fifty percent of patients were associated with generalized ligamentous laxity. Positive mid-carpal clunk test was most sensitive and specific to diagnose PMCI. Other common clinical features included: lax ulnar column, volar sagging of wrist, increased piso-styloid interval, wrist pain aggravated by passive hand supination and not by passive forearm supination, wrist pain upon resisted pronation, which could be partially alleviated by manually supporting the piso-styloid interval. Common arthroscopic findings were excessive joint space at triquetro-hamate interval and reactive synovitis over the ulnar compartments. Nine cases responded well to conservative treatments. Arthroscopic thermal shrinkage was performed in 4 patients with recurrence in 2 cases. Five patients received split FCU tendon graft for ligament reconstruction and all claimed satisfactory results and restored stability at a mean follow-up 86 months. Conclusion PMCI is not rare in Chinese population but can often be missed. Better understanding of its etiologies, pathomechanics and using systematic method of clinical evaluation helps to establish diagnosis, predict prognosis and management outcomes. Many cases are self-limiting and can be expected to improve over time under conservative treatment. Thermal shrinkage offers an interim and minimally invasive measure to control symptom. The new surgical method of dorsal radio-carpal ligament reconstruction with split FCU graft is relatively simple and provides reliable long-term relief of symptom.

The Effect of Lunate Morphology on the 3-Dimensional Kinematics of the Carpus

To assess carpal kinematics in various ranges of motion in 3 dimensions with respect to lunate morphology. Eight cadaveric wrists (4 type I lunates, 4 type II lunates) were mounted into a customized platform that allowed controlled motion with 6 degrees of freedom. The wrists were moved through flexion-extension (15°-15°) and radioulnar deviation (RUD; 20°-20°). The relative motion of the radius, carpus, and third metacarpal were recorded using optical motion capture methods. Clear patterns of carpal motion were identified. Significantly greater motion occurred at the radiocarpal joint during flexion-extension of type I wrist than a type II wrist. The relative contributions of the midcarpal and radiocarpal articulations to movement of the wrist differed between the radial, the central, and the ulnar columns. During wrist flexion and extension, these contributions were determined by the lunate morphology, whereas during RUD, they were determined by the direction of wrist motion. The midcarpal articulations were relatively restricted during flexion and extension of a type II wrist. However, during RUD, the midcarpal joint of the central column became the dominant articulation. This study describes the effect of lunate morphology on 3-dimensional carpal kinematics during wrist flexion and extension. Despite the limited size of the motion arcs tested, the results represent an advance on the current understanding of this topic. Differences in carpal kinematics may explain the effect of lunate morphology on pathological changes within the carpus. Differences in carpal kinematics due to lunate morphology may have implications for the management of certain wrist conditions.

Síndrome de impactación ulnocarpiano, manejo artroscópico

Ulnocarpal impaction is one of the most common causes of ulnar-sided wrist pain. It is a progressive degenerative condition caused by chronic impaction of the ulnar head against the triangular fibrocartilage (TFC) and the ulnar portion of the carpus. The aim of surgical treatment is to perform a decompression of the ulnar column of the wrist, in the ulnocarpal joint.With the advances in wrist arthroscopic surgery it is possible to shorten the ulnar head (Wafer procedure) by an arthroscopic approach, at the same time as assessing and treating the injuries associated with the ulnar impaction (TFC injuries, chondral injuries, lunopyramidal ligament tears, synovitis, etc.), thus allowing a more complete and accurate treatment, and with some very satisfactory results.

Antegrade Nailing Can Prevent Cubitus Varus and Valgus After Pediatric Supracondylar Fractures With Impacted Columns

Supracondylar fractures are commonly encountered in the pediatric population. An impacted radial or ulnar column may result in the deviation of the elbow axis in the frontal plane clinically seen as cubitus varus or valgus. Antegrade nailing has become a feasible alternative to treat supracondylar fractures. It is not known whether it can prevent the development of cubitus varus or valgus in the cases of fractures with impacted columns. Between 1994 and 2009, 264 supracondylar humeral fractures were treated. Nineteen patients presented with either an impacted ulnar (n = 12) or radial (n = 7) column and were included in the study. The average elbow angle in fractures with impacted radial column was 159° mean (range 153-167°) compared with 179° (range 173-184°) in fractures with an impacted ulnar column. After closed reduction and antegrade nailing, the elbow angle was restored to normal values. At follow-up examination after a mean of 3.8 years (range 2.4-7.6 years), no further changes of the humeral-ulnar angle were seen. We are able to show that antegrade nailing is a safe method to treat supracondylar humeral fractures with impacted columns.

Translating Carpal Biomechanics to Triangular Fibrocartilage Complex Injury: Significance of Ulnar Variance in Predicting TFCC Lesions

Ulnar variance (UV) describes the cranio‐caudal position of the distal ulna in relation to the distal radius at the wrist. Neutral ulnar variance (ulna and radius articulating at the carpus at exactly the same level) transmits 20% of the compressive load across the wrist to the distal ulna and 80% to the distal radius. A +2.5mm positive UV has been shown to increase the ulnocarpal load to 40%. The triangular fibrocartilage complex (TFCC) acts as a cushion for the ulnar carpus and transmits axial loads from the wrist to the ulna in a longitudinal direction across the ulnar column of the wrist. Consequently, a positive ulnar variance implicates a greater risk of TFCC injury. This study sought to calculate the prevalence of traumatic TFCC injury in those with a positive UV versus those with a negative UV. 20 cadaveric wrists aged 50 – 90 were assessed for TFCC damage via gross examination and classified according to Palmer's schema. A plain film PA radiograph of each wrist was then taken to measure the degree of UV. Results showed that all wrists had degenerative Class II lesions of the TFCC, while traumatic Class I lesions of the TFCC were found in 69% of wrists with positive UV as compared to 0% of wrists with negative UV (p&lt;0.05). Our investigation prompts further research exploring a “dose‐response” relationship between UV and TFCC damage as well as between the degree of TFCC damage and clinical symptoms or diminished quality of life.Grant Funding Source: SUNY Downstate College of Medicine Alumni Association

Distal radius fracture fixation with volar locking plates and additional bone augmentation in osteoporotic bone: a biomechanical study in a cadaveric model

Fractures of the distal radius represent the most common fractures in adults. Volar locked plating has become a popular method for treating these fractures, but has been subject to several shortcomings in osteoporotic bone, such as loss of reduction and screw purchase. In order to overcome these shortcomings, cement augmentation has been proposed. AO-type 23-A3.3 fractures were made in 8 pairs of fresh frozen osteoporotic cadaveric radial bones. All specimens were treated with volar plating, and divided into cement augmentation or non-augmentation groups (n = 8/group). Constructs were tested dynamically and load to failure, construct-stiffness, fracture gap movement and screw cutting distance were measured. Cement augmentation resulted in a significant increase in cycles and load to failure, as well as construct stiffness at loads higher than 325 N. When compared to the non-augmented group, fracture gap movement decreased significantly at this load and higher, as did screw cutting distance at the holes of the ulnar column. The cycles to failure depend on the BMD in the distal region of the radius. Cement augmentation improves biomechanical properties in volar plating of the distal radius.

Locking Reconstruction Double Plating of Distal Humeral Fractures: How Many Screws in the Distal Ulnar Column Segment in A3 Fracture Provide Superior Stability? A Comparative Biomechanical In Vitro Study

Two 90-degree configurations of locking reconstruction plates with different numbers of screws in the distal ulnar column segment of distal extra-articular humeral fractures with metaphyseal comminution (A3) were biomechanically investigated. Eight pairs of fresh-frozen human humeri were used. For paired comparison, the humeri were divided into 2 randomized groups. In both groups, double-plate osteosyntheses with locking reconstruction plates were performed in 90-degree configurations. In group 1, the posteriorly placed radial column plate exceeded the capitellum and the ulnar column plate extended into the ulnar sulcus. The ulnar plate was molded around the medial epicondyle and fixed with 3 short angular stable screws distally. In group 2, the posteriorly placed radial column plate was applied analogous to group 1. The locking reconstruction plate placed on the ulnar column was used reaching to the ulnar epicondyle, fixed with 1 long, angular, stable screw in the distal fragment. Stiffness testing for axial load and bending in static and cyclic tests were performed. In static test mode, a load was applied with a frequency of 0.1 Hz. For cyclic loading conditions, a load was applied at 1 Hz for 5000 cycles. All tested specimens adequately resisted simulated physiologic loading conditions with no failure. Comparable stiffness values for axial load (P = 0.161) and significant lower stiffness values for bending (P = 0.017) in group 2 under static bending conditions were found. Considering cyclic loading conditions, no significant alterations in stiffness in each group under axial load occurred. In bending conditions, stiffness values for group 2 were significantly lower than that for group 1 (P = 0.036). Under static and cyclic bending conditions, stiffness in group 2 was significantly lower than that in group 1. Nevertheless, both implant configurations showed no failure of the constructs. Based on these data, when applying locked plates in the clinical setting, more than 1 locked screw applied into the distal ulnar column of the articular segment is recommended.

A case report of coronal fractures through the hamate, the capitate, and the trapezoid

To our knowledge, the simultaneous coronal fractures of the hamate, capitate, and trapezoid have not been previously reported in the literature. There were few reports about coronal fractures of the hamate caused only by axial loading to the ulnar column. We report 43-year-old man who presented with painful swelling on the dorso-ulnar side of the wrist after striking a wall with his right clenched fist. The computed tomography scan demonstrated coronal fractures through the hamate, capitate, and trapezoid. We performed closed reduction and fixation with a percutaneous compression screw. At the last follow-up, the patient was able to return to sports activities without any symptoms.