Safe zones in dorsal portals for wrist arthroscopy: a cadaveric study.

The standard dorsal portals are the most commonly used in wrist arthroscopy. This cadaveric study aims to determine safe zones, by quantitatively describing the neurovascular relationships of the dorsal wrist arthroscopy portals: 1-2, 3-4, midcarpal radial, midcarpal ulnar, 4-5, 6-radial and 6-ulnar. The neurovascular structures of twenty-one fresh frozen human cadaveric upper limbs were exposed, while the aforementioned portals were established with needles through portal sites. The minimum distance between portals and: dorsal carpal branch of radial artery, superficial branch of radial nerve, posterior interosseous nerve and dorsal branch of ulnar nerve, were measured accordingly with a digital caliper, followed by statistical analysis of the data. The median and interquartile range for each portal to structures at risk were determined and a safe zone around each portal was established. Free of any neurovascular structure safe zones surrounding 1-2, 3-4, midcarpal radial, midcarpal ulnar, 4-5, 6-radial and 6-ulnar portals were found at 0.46mm, 2.33mm, 10.73mm, 11.01mm, 10.38mm, 5.95mm and 0.64mm respectively. Results of statistical analysis from comparisons between 1-2, 3-4 and midcarpal radial portals, indicated that 1-2 was the least safe. The same analysis among 3-4, midcarpal radial, midcarpal ulnar and 4-5 portals indicated that midcarpal portals were safer, while 3-4 was the least safe. Results among midcarpal ulnar, 4-5, 6-radial and 6-ulnar portals indicated that 6-radial and specifically 6-ulnar were the least safe. This study provides a safe approach to the dorsal aspect of the wrist, enhancing established measurements and further examining safety of the posterior interosseous nerve.

Ulnar-Sided Wrist Pain in the Athlete: Sport-Specific Demands, Clinical Presentation, and Management Options.

ABSTRACT: Ulnar-sided wrist injuries are common in sports that require repeated pronosupination, wrist radial/ulnar deviation, axial loading, and gripping equipment. Common anatomic structures affected include the triangular fibrocartilage complex, extensor carpi ulnaris tendon, distal radioulnar and ulnocarpal joints, and hamate bone. Presenting symptoms include pain with activity, swelling, possible snapping or clicking, and reproduction of symptoms with provocative maneuvers. Imaging may confirm or rule out pathologies, but abnormal findings also may present in asymptomatic athletes. Initial treatment is usually nonoperative with splinting, load management, activity modification, strengthening the components of the kinetic chain of the particular sport, and pain management. Surgery is usually indicated in ulnar-wrist pain pathology such as hook of hamate fractures and required in associated instability. Future research should address specific treatment and rehabilitation protocols, emphasizing the complete kinetic chain along with the injured wrist.

Cartilage and subchondral bone distributions of the distal radius: a 3-dimensional analysis using cadavers.

OBJECTIVE: To quantify the spatial distributions of cartilage and subchondral bone thickness of the distal radius. DESIGN: Using 17 cadaveric wrists, three types of 3-dimensional models were created: a cartilage-bone model, obtained by laser scanning; a bone model, rescanned after dissolving the cartilage; and a subchondral bone model, obtained using computed tomography. By superimposing the bone model onto the cartilage-bone and the subchondral bone models, the cartilage and subchondral bone thickness were determined. Measurements along with the spatial distribution were made at fixed anatomic points including the scaphoid and lunate fossa, sigmoid notch and interfossal ridge, and compared at each of these four regions. RESULTS: Cartilage thickness of the interfossal ridge (0.89 ± 0.23 mm) had a larger average thickness compared to that of the scaphoid fossa (0.70 ± 0.18 mm; p = 0.004), lunate fossa (0.75 ± 0.17 mm; p = 0.044) and sigmoid notch (0.64 ± 0.13 mm; p < 0.001). Subchondral bone was found to be thickest at the scaphoid (2.18 ± 0.72 mm) and lunate fossae (1.94 ± 0.93 mm), which were both thicker than that of sigmoid notch (1.63 ± 1.06 mm: vs scaphoid fossa, p = 0.020) or interfossal ridge (1.54 ± 0.84 mm: vs scaphoid fossa, p = 0.004; vs lunate fossa, p = 0.048). In the volar-ulnar sub-regions of the scaphoid and lunate fossa, the subchondral bone thickened. CONCLUSIONS: Our data can be applied when treating distal radius fractures. Cartilage thickness was less than 1 mm across the articular surface, which may give an insight into threshold for an acceptable range of step-offs. The combined findings of subchondral bone appreciate the importance of the volar-ulnar corner of the distal radius in the volar locking plate fixation.

Anatomical relationship between the morphology of the styloid process of the ulna and the attachment of the radioulnar ligaments.

The radioulnar ligaments are the major stabilizers of the distal radioulnar joint under dynamic loading; however, anatomical detail regarding their attachment on the middle and distal thirds of the styloid process of the ulna remains unclear. Because previous anatomical studies included only old cadavers, their anatomical findings might not reflect the morphological features of younger and healthy specimens. This study investigated the anatomical features of the distal ulna, particularly the styloid process, to determine the attachment of the radioulnar ligaments to the styloid process and verified their direction and attachment to the styloid process in younger and healthy donors using magnetic resonance imaging (MRI). We investigated the morphological features of the distal ulna of 12 cadaveric wrists using micro-computed tomography (micro-CT). We also visualized and measured the distribution of the cortical bone thickness. We histologically analyzed three specimens in the axial plane and macroscopically analyzed seven specimens to examine the attachment of the radioulnar ligaments to the styloid process. In addition, we evaluated five wrists from living volunteers using 3.0 Tesla MRI. The distal ulna has a ridge on the dorsoradial aspect of the styloid process that corresponds to the attachment of the radioulnar ligaments. Micro-CT images after data processing revealed that the cortical thickness of the dorsoradial quadrant was thicker than that of the other quadrant at the proximal slice of the styloid process (p < 0.01), and that of the dorsoulnar (p = 0.021) and ulnopalmar (p < 0.01) quadrants at the middle slice. Histological analyses showed that the radioulnar ligaments were attached to the middle and distal thirds of the styloid process via chondral-apophyseal entheses. The direction of the fiber was dorsal in the middle third of the styloid process and changed to palmar in the distal third of the styloid process. The direction and attachment of the radioulnar ligaments on the styloid process were confirmed using MRI for younger and healthy participants. The radioulnar ligaments were attached to the dorsoradial ridge of the styloid process, which was confirmed by cortical bone thickening, histology at the attachment sites, and in vivo MR imaging. The directions of the radioulnar ligaments sterically intersected, which would satisfy both slipping stability and rotational mobility. These anatomical findings may provide the basis for biomechanical consideration of distal radioulnar joint stabilization.

Imaging study of coronal structural matching of the distal radius in normal adults.

BACKGROUND: As an important anatomical basis, coronal structural position matching of the distal radius has long been lacking in terms of a quantitative understanding, and such matching is correlated with the postoperative functional recovery of patients with distal radius fracture. The purpose of this study was to explore the degree of coronal structural matching of the distal radius in a normal population and to improve the detailed anatomical knowledge of the distal radius. METHODS: The reconstructed 3D data were analysed using 3-matic research software from thin-film CT images of 80 normal adults, and the coronal structural matching of the distal radius was studied from two aspects: 1) self-matching of the distal radius; and 2) matching between the distal radius and ulna (i.e., the joint space of the distal radioulnar joint). Specific research methods: 1) The relative position of the medial wall of the distal radius with respect to the lunate was determined as the percentage (%) of the vertical distance from the medial wall of the radius to the most prominent ulnar point of the lunate in the corresponding plane from the ulna to the radius. 2) A total of 9 sets of data were collected for evaluating the palmar lateral spacing, median spacing, and dorsal lateral spacing at the distal, middle, and proximal levels of the radius. RESULTS: In the study, 9 sets of data were obtained. And the data of self-matching of the coronal structural of distal radius was also obtained, was 45.0% ± 16.2%. The P values in the above data were all greater than 0.05, showing no statistical significance. Finally, data of coronal bone structural matching of distal radius in 80 normal adults were obtained. CONCLUSIONS: Our study refines the anatomical data of the degree of coronal bone structural matching of the distal radius in a normal population. To explore the relationship between coronal alignment and function in cases of distal radius fracture, a standardized approach was established. Thin- film CT may help diagnose patients with dysplasia around the lunate and radioulnar joint that is difficult to diagnose on MRI.

The course of posterior interosseous nerve in the wrist capsule. An anatomical study using the modified Sihler's staining.

The aim of the study was to assess the course of posterior interosseous nerve in the wrist capsule in the transparent method of nerve staining. MATERIAL AND METHODS: Thirty dorsal wrist capsules were collected bilaterally from 15 donors (thirty capsules) within 12 hours of death. By the dorsal incision the capsules were collected in the same manner. The specimens were stained according to the protocol of modified Sihler's staining technique. The preserved capsules were analysed under 8-16× magnification of optical microscope for the presence of major posterior interosseous nerve trunks, their major and minor branches, and nerve connections. RESULTS: Three main types of nerve course were identified within the joint capsule. Type I - the most common, with the presence of a single trunk with the excursion of the first main branch on the radial side, two main branches on the ulnar side, the presence of the prevailing number of small branches on the radial side and the presence of 3-4 branches extending beyond the level of the carpo-metacarpal joints. Type II with the presence of two main nerve trunks, running almost in parallel with the first main branch on the radial side, two main branches on the ulnar side with presence of a predominant number of small branches on the radial side and the presence of 3-4 branches running beyond the level of carpo-metacarpal joints. Type III (least often) with the presence of crossed main nerve trunks. CONCLUSION: The modified Sihler's staining technique allows for transparent visibility of the nerves innervation the dorsal wrist capsule. However does not allow accurate assessment as histological examination, especially in evaluation of nerve endings, but it gives a significantly larger area of nerve observation.

Three-dimensional geometric morphometric analysis of the distal radius insertion sites of the palmar radiocarpal ligaments in hominoid primates.

OBJECTIVES: To identify anatomic differences in the insertion sites of the palmar radiocarpal ligaments in different species of hominoid primates that may be related to their different types of locomotion. MATERIALS AND METHODS: We have used three-dimensional geometric morphometrics (3D GM) to analyze the distal radius ligament insertion sites in 31 Homo sapiens, 25 Pan troglodytes, 31 Gorilla gorilla, and 15 Pongo pygmaeus. We have also dissected the radioscaphocapitate (RSC), long radiolunate (LRL) and short radiolunate (SRL) ligaments in six H. sapiens and five P. troglodytes to obtain quantitative values that were then compared with the results of the 3D GM analysis. RESULTS: H. sapiens had a relatively larger insertion site of the RSC + LRL ligament than the other hominoid primates. P. pygmaeus and P. troglodytes had a relatively large SRL ligament insertion site with a palmar orientation. In G. gorilla, the two ligament insertion sites were relatively smaller and the SRL insertion site had an ulnopalmar orientation. DISCUSSION: The morphological differences observed can be related to the types of locomotion used by the different species and to quantitative data obtained from the dissection of ligaments in H. sapiens and P. troglodytes. 3D GM analysis of ligament insertion sites can help in interpreting the types of locomotion used by extinct hominoid primates through the analysis of preserved fossilized fragments of the distal radius.

Persistent Median Artery as an Unusual Finding in the Carpal Tunnel: Its Contribution to the Blood Supply of the Hand and Clinical Significance.

BACKGROUND Knowledge of the variable relation of the persistent median artery (PMA) to the median nerve and its contribution to the formation of the superficial palmar arch is of great clinical significance. This study presents a proposal of specific variables which might be introduced to characterize the PMA in the wrist region. MATERIAL AND METHODS One hundred and twenty-five randomly selected, isolated upper limbs fixed in 10% formalin solution were subjected to anatomical dissection. RESULTS Of the 125 upper limbs, PMA was found in 5 specimens (4% of the total number of limbs). In the carpal tunnel, the artery occupied the anterolateral position (2 cases), the anterior position (2 cases) or the anteromedial position (1 case) in relation to the median nerve. Two types of superficial palmar arches with significant contributions from the PMA were observed in the studied material: complete medio-ulnar arch and an incomplete arch without a connection between the territories of the ulnar and median arteries. The mean ratio of the diameter of the PMA to the diameter of ulnar artery at the level of the wrist was 0.59 (min.=0.38, max=0.83, SD=0.19). CONCLUSIONS Orthopedic and hand surgeons should be aware of the probability of occurrence of the PMA in both planning and conducting surgeries within the wrist region and within the carpal tunnel, as this anomalous vessel might present significant contributions to the arterial blood supply of the hand and might potentially play an important role in the presence of notable clinical symptoms and presentations.

A new radiographic view of the scaphotrapeziotrapezoid joint-a cadaveric study.

BACKGROUND: The scaphotrapeziotrapezoid joint (STTJ) has a complex osseous and ligamentous anatomy. Precise radiographic assessment is paramount when assessing osteoarthritic, post-traumatic, or post-operative patients. There has been no described technique to image the STTJ without any wrist movement, unobscured by the rest of the carpus. The aim of this study was to define an optimal radiographic method to assess the STTJ while maintaining the wrist in neutral position. METHODS: Computer tomography 3-D reconstructions of three uninjured wrists were initially used to determine an approximate beam angle. Serial radiographs of 12 cadaveric wrists were taken. The forearms were positioned in varying degrees of pronation and supination. The beam angle was concurrently adjusted to varying degrees of caudal tilt. From the images obtained, we assessed if the adjacent carpus obscured the view of the STTJ. RESULTS: Optimal STTJ imaging was in the semi-pronated wrist position with the X-ray beam tilted caudal. We found that the STTJ was best visualized at 48° supination from a fully pronated wrist and a caudal beam angle of 22°. CONCLUSIONS: The described wrist and beam orientation can aid in achieving an unobstructed view of the STTJ with little technical effort. This can aid in imaging ambulatory patients where symptoms prevent using other imaging techniques as well as patients in the operating room where imaging timing can be critical.

Volar Midcarpal Portals in Wrist Arthroscopy.

PURPOSE: To describe the placement of volar midcarpal portals using the inside-out technique, and the surrounding anatomical structures at risk. METHODS: Five fresh-frozen cadavers were used. Volar ulnar midcarpal (VUMC) and volar radial midcarpal (VRMC) portals were placed using an inside-out technique. The distance between these portals to surrounding anatomical structures was measured in millimeters using a caliper. RESULTS: The VUMC portal pierced the flexor digitorum profundus tendon to the middle finger in 1 specimen. The portal was an average 3.7 and 8.4 mm away from the ulnar artery and nerve, respectively. The VRMC portal pierced the palmaris longus in 2 specimens. It usually was between the flexor pollicis longus, the palmaris longus, and the median nerve. It was an average of 1.0 and 1.95 mm away from the median nerve and palmar cutaneous branch of the median nerve, respectively and in 1 specimen, was in contact with the median nerve after piercing the mesoneurium. CONCLUSIONS: With increasing use of volar midcarpal arthroscopy, the surgeon needs to have an understanding of the structures at risk when placing the VUMC and VRMC portals. CLINICAL RELEVANCE: When developing the volar midcarpal portals, the surgeon needs to pay close attention to the anatomical structures at risk and, in particular, the median nerve from the VRMC portal.

Image-Based Comparison Between the Bilateral Symmetry of the Distal Radii Through Established Measures.

PURPOSE: Anthropometric assessment of bony structures in the body is important for preoperative computer-aided surgery, implant design, finite element modeling, and biomechanical studies investigating joint structure and function. The use of the contralateral limb in surgery and clinical practice relies on the assumption that the right and left limbs of an individual are symmetric. Therefore, the purpose of this study was to quantify the bilateral symmetry of the bony structures of the distal radius using 3-dimensional (3D) computed tomography. METHODS: We collected computed tomography images of 37 paired, fresh-frozen, healthy cadaveric male upper limbs (aged 75.4 ± 8.3 years). Three-dimensional reconstructed models were created using semiautomatic segmentation. Using the 3D models, we measured 3D radial inclination, 3D volar tilt, 3D radial height, medial volar cortical angle, middle volar cortical angle, and lateral volar cortical angle and compared them between sides. RESULTS: There were no statistically significant differences measured between right and left distal radius in 37 paired wrists. Mean radial height was 12.81 mm (SD, 1.74 mm) on the left and 12.88 mm (SD, 1.72 mm) on the right. Mean volar tilt was 10.74° (SD, 3.74°) and 10.77° (SD, 3.19°) and radial inclination was 24.05° (SD, 2.63°) and 24.18° (SD, 3.41°) on the left and right, respectively. Mean volar cortical angle across the radius was 140.9° (SD, 7.9°) on the left and 140.1° (SD, 7.9°) on the right. CONCLUSIONS: Direct bilateral comparison of the distal radius and wrist joints is useful to predict normal anatomy of the injured radius, because bilateral similarities exist. CLINICAL RELEVANCE: This article provides a comprehensive list of measurements of the distal radius compared bilaterally using a 3D model. From this study, we found that the contralateral radius can be used as a benchmark with which to compare fracture reduction and to manage malunions during the preoperative planning of corrective osteotomies. It can also be used to define normal anatomy.

An Anthropometric Assessment of the Proximal Hamate Autograft for Scaphoid Proximal Pole Reconstruction.

PURPOSE: Fragmentation of the scaphoid proximal pole secondary to avascular necrosis presents a difficult reconstructive problem. This anthropometric study assesses the utility of the ipsilateral proximal hamate for complete osteochondral scaphoid proximal pole reconstruction. METHODS: Twenty-nine cadaveric specimens underwent computed tomography scanning and 3-dimensional reconstruction of the carpus and distal radius. Scaphoid height was measured and a third of its height was used to simulate resection of the proximal scaphoid pole and extent of hamate autograft required. The proximal scaphoid and hamate were divided into 6 sections, and compared using an iterative point-to-point distance algorithm. Average distance between the scaphoid and the hamate surfaces was determined. An interbone algorithm was used to assess radioscaphoid joint congruency and articular contact surface of the native scaphoid compared with the scaphoid reconstructed with hamate autograft. RESULTS: The mean height of scaphoid proximal pole excision and proximal hamate autograft height was 9.3 mm. Comparing the morphology of the native scaphoid and hamate autografts, the absolute distances were the largest in the volar radioscaphoid, dorsal radioscaphoid, and dorsal scaphocapitate segments. Without osteotomy, the hamate autograft may cause impaction in the dorsal-radial aspect of the distal radius. The hamate autograft also shifted the articular contact point of the radioscaphoid joint toward the dorsal-radial position. Nine hamate autografts were classified as poor-fitting. Poor-fitting specimens had a greater radial styloid to distal radioulnar joint distance. These specimens also had wider hamates and scaphoids in the radial-ulnar dimension and wider scaphoids in the volar-dorsal dimension. Lunate type did not correspond to anthropometric fit. CONCLUSIONS: The proximal hamate osteochondral graft was poor fitting in 31% of cases (9 of 29 specimens). Wrists with radial-ulnar hamate width less than 10 mm, radial-ulnar scaphoid width less than 10 mm, and volar-dorsal scaphoid width less than 16 mm demonstrate better anthropometric fit. CLINICAL RELEVANCE: This study provides an anthropometric assessment of the recently described proximal hamate autograft, a new bone graft option for proximal scaphoid pole reconstruction.

Bony anatomy of the third metacarpal and relationship with the capitate: a computed tomography study.

PURPOSE: The purpose of this study was to accurately establish the anatomical variability of the third metacarpal, its medullary canal, and the relationship with the capitate in the context of high rates of component loosening still seen in total wrist arthroplasty. METHODS: CT scans of a 100 hands (age: 41 ± 14 years (range: 16-71 years); male/female ratio: 53/47) were studied to establish the detailed anatomy of the third metacarpal and the capitate. RESULTS: Although the shape of the third metacarpal and the angles formed with the capitate were highly variable, the third metacarpal length was longer in males (p < 0.001), the proximal cortical bone was thicker (p < 0.001) and the sagittal metacarpal-capitate axis offset was greater (p = 0.01). A relationship was found between the total length of the metacarpal and the distance to the isthmus from the base (r = 0.63; p < 0.0001) which was unaffected by gender. No age-related relationships were significant. CONCLUSION: The anatomy of the third metacarpal and capitate varies considerably more than has been alluded to in current wrist arthroplasty literature. Differences between males and females can likely be attributed to hand size. The distance of the isthmus from the base can be predicted from the total length of the metacarpal with a standard error of 1.9 mm.

Anatomical-positional relationship between the bone structure of the distal radius and flexor pollicis longus tendon using ultrasonography.

PURPOSE: In this study, using an ultrasonography, we investigated the positional relationship between the volar bone cortex of distal radius and flexor pollicis longus (FPL) tendon in the distal radius of healthy subjects. METHODS: The subjects were 32 healthy volunteers (56 wrists) (Age 32.9 ± 8.5, 16 males and 16 females). Their wrists were imaged by an ultrasonography. The distances between the watershed line (WS) and FPL (A), between the distal margin of pronator quadratus (DMPQ) and FPL (B), between the FPL and volar radial bone cortex at the maximum muscle belly of the PQ muscle right below the sliding region of the FPL tendon (C), and between the WS and DMPQ (D) were measured. RESULTS: All these parameters showed a normal distribution. When the correlation among the parameters was investigated, a correlation with an index of the physique, BMI, was noted in A (P < 0.01), B (P < 0.01), and C (P < 0.01), but no correlation was noted only in D (P = 0.59). CONCLUSIONS: Our results were suggested that when distal radius fracture is treated with a distal plate placement, the appropriate placement can be achieved by applying about 3 mm additional dissection of soft tissue on the volar bone cortex distal to the DMPQ.

Safe zones in volar portals for wrist arthroscopy, evaluation of central portal : a cadaveric study.

The purpose of this cadaveric study is to determine safe zones utilizing volar portals for wrist arthroscopy, by quantitatively describing the neurovascular relationships of a volar radial and a volar ulnar wrist arthroscopy portals in comparison with those of a newly described volar central portal (7) , considering the advantages in visualization of volar portals for wrist arthroscopy over the standard dorsal (19) . The neurovascular structures and the tendons of nine frozen human cadaveric upper limbs were exposed, while the aforementioned volar portal sites were pointed out with pins. The horizontal distance between the portals and the closest neurovascular branch or tendon was measured with a digital caliper, followed by statistical analysis of the data. The median interquartile range distances from portals to structures at risk were measured and safe zones around each portal were established. This study provides a safe approach to the volar radial and ulnar aspects of the radiocarpal and midcarpal joints, while volar radial and ulnar portals should be considered for inclusion in the arthroscopic examination of any patient with radial and ulnar sided wrist pain respectively (17,18) . Regarding the volar central portal, it is reproducible, safe and both the above joints can be inspected through one single incision (7) .

[Relationship of BMI and wrist joint index with carpal tunnel syndrome in manual laborers].

Objective: To evaluate the severity of median nerve damage in patients with carpal tunnel syndrome (CTS) , and to analyze its relationship with body mass index (BMI) and wrist joint index. Methods: From May 2016 to January 2017, 23 patients with mild CTS (mild group) and 35 patients with moderate to severe CTS (moderate to severe group) were enrolled in this study. And 22 healthy volunteers matched for sex and age were selected as control group. The neuroelectrophysiological monitor was used to measure the median nerve movement and sensory nerve conduction in the subjects. The BMI and wrist joint index were calculated. The relationship of neuroelectrophysiological parameters with BMI and wrist joint index was analyzed in the CTS patients. Results: Compared with the control group, the mild group and the moderate to severe group had significantly higher wrist joint index, significantly longer distal motor latency (DML) of the median nerve, and significantly lower sensory nerve conduction velocity (SNCV) and sensory nerve action potential (SNAP) amplitude of the finger 1-wrist and finger 3-wrist (P<0.01) ; the moderate to severe group had significantly higher BMI and significantly lower composite muscle action potential (CMAP) amplitude (P<0.01) . The wrist joint index and BMI were positively correlated with DML of the median nerve and negatively correlated with SCV and SNAP amplitude of the finger 1-wrist and finger 3-wrist (all P<0.05) . The patients with a wrist joint index of >0.73 had a significantly higher risk of CTS than those with a wrist joint index of <0.73 (odd ratio=30.67, 95% confidence interval: 3.79-248.36) . Conclusion: A wrist joint index of >0.73 is an independent risk factor for CTS in manual laborers. CTS should be prevented in the manual laborers with high wrist joint index and BMI.

Distal radius fluoroscopic skyline view: extension-supination versus flexion-supination.

The aim of our study was to compare the vertical fluoroscopic view of the wrist in extension and supination (ES) to the view in flexion and supination (FS) and determine which of the two views allowed the best visualization of four selected anatomical landmarks SDLR (radial styloid, dorsal radius cortex, Lister's tubercle and distal radioulnar joint). Our case series included 50 patients who had suffered a distal radius fracture and undergone an open reduction and internal fixation procedure with a volar locking plate. For each case, two fluoroscopic views were taken: ES (wrist extension and supination) (group I) and FS (wrist flexion and supination) (group II). Ten observers had to recognize the SDLR anatomical landmarks on 100 fluoroscopic skyline views (time 1) and 15 days later (time 2). The rate of recognition of the four anatomical landmarks was 78% in group I and 66% in group II (p < 0.001). The concordance rate of recognition of the four anatomical landmarks was mediocre (κ = 0.411). In conclusion, the vertical fluoroscopic skyline view in wrist extension and supination seems to be the most adequate view to assess the quality of the fracture reduction, the distal radioulnar joint and the length of the screws in open reduction and internal fixation of distal radius fractures with volar locking plates.

Wrist and Hand Ultrasound: Reliability of Side-to-Side Comparisons of Very Small (<2-mm) Clinically Relevant Anatomic Structures.

OBJECTIVES: In ultrasound (US) examinations of clinically relevant very small structures of the wrist and hand, the healthy contralateral side can be used as a reference to identify subtle abnormalities. Intraindividual side-to-side variability must be minimal. The aim of this study was to assess the reliability of side-to-side US evaluations of very small structures of the wrist and hand. METHODS: Forty-one healthy volunteers were prospectively studied. Small structures of the wrist and hand were evaluated bilaterally by 2 musculoskeletal radiologists in separate sessions. The first annular pulleys of the second finger and the thumb, sagittal band of the third finger, extensor and flexor retinacula, ulnar collateral ligament of the thumb, radial collateral ligament of the second finger, and palmar cutaneous branches of the median and ulnar nerves were considered. To assess intra- and inter-reader agreement, 10 of 41 (24%) examinations were repeated. Nonparametric statistics were used. RESULTS: Data were not normally distributed (P > .001). Intra-reader agreement was κ = 0.674 (95% confidence interval [CI], 0.57-0.78), and inter-reader agreement was κ = 0.935 (95% CI, 0.92-0.95). The mean value ± SD for all of the structures was 0.78 ± 0.44 mm. The overall coefficient of variation was 9.8% ± 0.07%. The intraclass correlation coefficient was 0.97 (95% CI, 0.96-0.98). CONCLUSIONS: In clinical practice, the healthy contralateral side can be used as a reference during a real-time musculoskeletal US evaluation of small (<2-mm) structures.

Anatomy and injuries of the pediatric wrist: beyond the basics.

Ligamentous injuries of the pediatric wrist, once thought to be relatively uncommon, are increasingly recognized in the context of acute high-energy mechanism trauma and chronic axial loading, including those encountered in both recreational and high-performance competitive sports. Recent advances in MR-based techniques for imaging the pediatric wrist allow for sensitive identification of these often radiographically occult injuries. Detailed knowledge of the intrinsic and supportive extrinsic ligamentous complexes, as well as normal developmental anatomy and congenital variation, are essential to accurately diagnose injuries to these structures. Early identification of ligamentous injury of the pediatric wrist is essential within the conservative treatment culture of modern pediatric orthopedics because treatment of these lesions often necessitates surgery, and outcomes often depend on early and sometimes aggressive intervention. In this article, we review MR arthrogram technique and pediatric wrist anatomy, and correlate appearances on MR and selected ligamentous pathologies of the pediatric wrist.

Treatment of Recurrent and Persistent Carpal Tunnel Syndrome: The Fasciocutaneous Dorsal Ulnar Artery Flap.

Surgical treatment of recurrent and persistent carpal tunnel syndrome by repeat carpal tunnel release combined with soft tissue nerve coverage results in a higher success rate for symptomatic relief in the presence of a scarred median nerve. Several techniques, including local pedicled flaps, transposition flaps from the distal forearm, and free flaps, have been described, but consensus regarding a preferred technique has not been reached. The dorsal ulnar artery flap or Becker flap is a local fasciocutaneous flap based on a dorsal perforating branch of the ulnar artery that can be used for soft tissue coverage of the median nerve. Advantages of this technique are the quick and easy dissection and low donor site morbidity. Studies of its use for the treatment of recurrent carpal tunnel syndrome are limited.