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Journal of Wrist Surgery Mar 2016Background In intra-articular fracture of distal radius, the intra-articular fragments can be divided into some specific fragments. In particular, the poor outcomes...
Background In intra-articular fracture of distal radius, the intra-articular fragments can be divided into some specific fragments. In particular, the poor outcomes have been well documented for reduction loss of the volar lunate facet, but the effect of a displaced dorsal rim fracture has rarely been addressed. Materials and Methods The records of 26 patients with dorsal rim fragment displaced by more than 2 mm after volar locking plate (VLP) fixation for a dorsally displaced distal radius fracture (DRF) treated from March 2006 to March 2009 were retrospectively reviewed. Clinical assessments including grip strengths, wrist range of motions, and Disabilities of Arm, Shoulder, and Hand (DASH) scores were performed at 12 months postoperatively. Widths of the distal ends of dorsal rims were determined by preoperative computed tomography (CT). Dorsal rim fragment displacements were measured in immediate postoperative plain lateral radiographs. Radial inclination, volar tilt, and ulnar variance were measured on immediate postoperative wrist radiographs. Arthritic changes of radiocarpal joints were graded using radiographs obtained at 12 months postoperatively. Description of Technique DRFs were fixed using a VLP in the usual manner. Although DRF displacement was noticed after plate fixation, no further procedure was performed. The sizes of articular portions of dorsal rim fragments were measured arthroscopically in 5 of the 26 patients at the time of plate fixation. Results At 12 months postoperatively, mean grip strength, wrist flexion arc, and mean wrist extension arc were 86 ± 13, 87 ± 11, and 91 ± 10%, respectively, of contralateral sides. Mean forearm supination and pronation were 96 ± 8 and 99 ± 5%, respectively, of contralateral sides. Mean DASH score was 11 ± 10 points. Preoperatively, mean width of the distal end of dorsal rim fragments and mean displacements of dorsal rim fragments were 2.0 ± 0.6 and 3.0 ± 0.9 mm, respectively. Mean width of the articular portions of dorsal rim fragment by arthroscopic examination was 1.0 ± 0.4 mm. Mean radial inclination was 21 ± 4.8 degrees, mean volar angulation was 4.8 ± 3.9 degrees, and mean ulnar variance was 0.6 ± 1.8 mm at immediate postoperatively. Two patients showed grade I arthritic changes at 12 months postoperatively. Conclusions The articular portions of dorsal rim fragments measured arthroscopically were smaller than determined by CT. Furthermore, the study shows that displaced dorsal rim fragments in dorsally displaced DRFs treated by VLP do not adversely affect wrist clinical outcomes.
PubMed: 26855833
DOI: 10.1055/s-0035-1571184 -
Hand (New York, N.Y.) Dec 2022Distal-ulna stump (DUS) instability often occurs when performing a distal radioulnar joint (DRUJ) arthroplasty. Recent studies suggest that the distal interosseous...
BACKGROUND
Distal-ulna stump (DUS) instability often occurs when performing a distal radioulnar joint (DRUJ) arthroplasty. Recent studies suggest that the distal interosseous membrane (DIOM) reinforces the triangular fibrocartilage complex, providing additional stability to the DRUJ. The aim of this study was to determine whether the DIOM stabilizes the ulnar stump.
METHODS
Twenty fresh-frozen random forearms were dissected. The presence of a distal oblique bundle (DOB) was recorded and measured. The radius was fixed to a vise and the ulna kept free. The DRUJ was fixed with a lag screw. A bone slice was removed by transverse ulna osteotomies 10 and 15 mm proximal to the DRUJ. A 10-N force was applied to the ulna in dorsal and volar directions. Displacements were measured. The DIOM was then transected, and maneuvers and measurements were repeated and compared.
RESULTS
A distinct distal membrane was present in 70% and a cord-like DOB in 30%. The mean length was 29 mm. Its origin was proximal to the sigmoid notch; its insertion was on the distal third of the ulna, at its lateral border. This attachment is comprised between 39 and 48 mm proximal to the ulnocarpal joint. Initial displacements averaged 22 mm dorsally and 13 mm volarly. After DIOM transection, ulnar translocation increased to 31 mm dorsally and 19 mm volarly.
CONCLUSION
In DRUJ arthroplasties, the DIOM does not appear to be a stabilizer of the DUS beneath a useful threshold. Its retaining effect occurs only after an initial 22-mm dorsal displacement, which we consider not clinically admissible. Therefore, in DRUJ arthroplasties, some augmentation might be advisable.
Topics: Humans; Interosseous Membrane; Joint Instability; Biomechanical Phenomena; Cadaver; Ulna
PubMed: 34144664
DOI: 10.1177/1558944721999728 -
The Journal of Physiology Dec 19811. Extracellular and intracellular recordings were made from dorsal horn neurones sending their axons through the dorsal columns in cats anaesthetized with chloralose...
1. Extracellular and intracellular recordings were made from dorsal horn neurones sending their axons through the dorsal columns in cats anaesthetized with chloralose and paralysed with gallamine triethiodide. 2. Seventeen neurones were injected with horseradish peroxidase through the intracellular micro-electrode, recovered from the histological material and shown to send their axons into the dorsal columns. 3. The cells had axonal conduction velocities of 30--47 ms-1; excitatory receptive fields that usually showed multireceptive characteristics, often including input from sensitive mechanoreceptors in glabrous skin; a third of the sample had a marked subliminal fringe to the excitatory field; inhibitory fields were usually situated proximal to the excitatory field and contiguous with it. 4. The cells were located in laminae III, IV and medial V. Dorsal cells had restricted dendritic trees that ascended in an essentially cylindrical volume of tissue through lamina II and often into I; cells intermediate in depth had more primary dendrites than the others, usually dorsally directed into lamina II, and a more extensive rostro-caudal development; deep, medial cells had dendritic trees that radiated extensively from the cell body but were restricted to the transverse plane. Two cells had axons that ascended the dorsolateral funiculus for a few mm before re-entering the dorsal horn, crossing it and reaching the dorsal columns. Collaterals were given off the axons in the grey matter, in the dorsolateral funiculus and the dorsal columns. 5. The form and function of the neurones are discussed.
Topics: Animals; Axons; Cats; Dendrites; Evoked Potentials; Horseradish Peroxidase; Neural Conduction; Neural Pathways; Neurons; Spinal Cord
PubMed: 7338813
DOI: 10.1113/jphysiol.1981.sp013970 -
Cureus May 2020A 19-year-old female presented with pain, deformity, and slightly restricted left wrist motion for five years with gradual progression. Physical examination revealed...
A 19-year-old female presented with pain, deformity, and slightly restricted left wrist motion for five years with gradual progression. Physical examination revealed volar subluxation of the left hand, dorsally prominent ulnar styloid, radial and dorsal bowing of the distal forearm, and mild restriction in wrist dorsiflexion. Radiographs showed a failure of ossification of the ulnar side of the distal radial epiphysis, increased radial inclination angle, dorsal subluxation of the distal ulna, V-shaped proximal carpal row due to proximal migration of the lunate, and increased interosseous space. A diagnosis of Madelung deformity of the left wrist was made. Conservative management with oral analgesics, activity restriction, and a volar splint was done as the patient was skeletally mature, had only mild pain with no functional limitation or gross deformity. At the six-month follow-up, she was doing well with decreased pain and no new complaints.
PubMed: 32582486
DOI: 10.7759/cureus.8225 -
JB & JS Open Access 2021The use of low-profile dorsal and volar locking plates for distal radial fracture surgery has improved results and lowered the complication rate compared with older...
Volar Locking Plate Versus Dorsal Locking Nail-Plate Fixation for Dorsally Displaced Unstable Extra-Articular Distal Radial Fractures: Functional and Radiographic Results from a Randomized Controlled Trial.
UNLABELLED
The use of low-profile dorsal and volar locking plates for distal radial fracture surgery has improved results and lowered the complication rate compared with older plate designs. The purpose of the present randomized controlled trial was to compare patient-reported outcomes as well as radiographic and functional results between patients who underwent stabilization with a volar locking plate or a dorsal locking nail-plate for the treatment of dorsally displaced unstable extra-articular distal radial fractures.
METHODS
One hundred and twenty patients ≥55 years of age were randomized to surgery with either a volar locking plate or a dorsal locking nail-plate and were assessed at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year. The primary outcome was the abbreviated version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score. Secondary outcomes were the Patient-Rated Wrist Evaluation (PRWE), EuroQol 5 Dimensions (EQ-5D) index and visual analog scale (VAS), range of motion, grip strength, radiographic measurements, and complication rate.
RESULTS
The median age was 66 years (range, 55 to 88 years). The rate of follow-up was 97%. There was no clinically important difference between the groups at any point during follow-up. Patients in the volar locking plate group had better mean QuickDASH scores at 6 weeks, 6 months, and 1 year. However, the differences were small (5.8 vs. 11.3 points at 1 year; mean difference, -5.5 points [95% confidence interval (CI), -9.9 to 1.2]; p = 0.014), which is lower than any proposed minimum clinically important difference (MCID). The difference in PRWE scores was also lower than the MCID (1.0 vs. 3.5 at 1 year; mean difference, -2.5 [95% CI, -4.4 to 0.6]; p = 0.012). The dorsal locking nail-plate group had slightly better restoration of volar tilt (p = 0.011). EQ-5D index, EQ-5D VAS, range of motion, grip strength, and complication rates were similar.
CONCLUSIONS
We found no clinically relevant difference between the volar locking plate and dorsal locking nail-plate groups after 1 year or in the time period up to 1 year. A dorsal locking nail-plate can therefore be an alternative method for the treatment of these unstable fractures or in cases in which a dorsal approach is preferable over a volar approach.
LEVEL OF EVIDENCE
Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.
PubMed: 34651093
DOI: 10.2106/JBJS.OA.21.00068 -
Joint Diseases and Related Surgery 2023The aim of this study was to evaluate the relationship between the length of the protruded screws from the dorsal cortex and extensor tendon damage in all compartments.
OBJECTIVES
The aim of this study was to evaluate the relationship between the length of the protruded screws from the dorsal cortex and extensor tendon damage in all compartments.
PATIENTS AND METHODS
Between May 2020 and April 2021, a total of 29 patients (13 males, 16 females; mean age: 52.3±13.0 years; range, 30 to 78 years) who were operated and followed in our clinic for AO A2 and A3 distal radius fractures were included in this prospective study. Surface ultrasound (US) imaging was made to the dorsal sides of both wrists of the operated patients at different timepoints postoperatively. The length of screws with radius dorsal cortex penetration and the presence of tendinitis were recorded.
RESULTS
In 15 of 23 patients, the presence of 29 protruding screws was accompanied by tendinitis and, in eight patients, no tendinitis was observed, despite the partial protrusion of screws. A statistically significant correlation was found between the screw protrusion and presence of tendinitis (p<0.05). The number of protruding screws and tendinitis were seen mostly in the second compartment. There was a statistically significant correlation between the protruding screw length of >1.6 mm and the presence tendinitis (p<0.05).
CONCLUSION
Dorsal cortex screw protrusions in the application of volar plate for distal radius fractures can cause tendinitis. Screw protrusions occur more frequently in the second compartment and the development of tendinitis in this compartment is associated with a screw length of >1.6 mm. Screw penetration can be easily identified with intraoperative US to prevent tendinitis and potential tendon ruptures.
Topics: Male; Female; Humans; Adult; Middle Aged; Aged; Radius Fractures; Prospective Studies; Fluoroscopy; Radius; Bone Screws; Wrist Fractures
PubMed: 36700271
DOI: 10.52312/jdrs.2023.856 -
Frontiers in Veterinary Science 2020Laminitis is a debilitating disorder resulting in irreversible anatomical changes in the feet of equids. Assessing specific anatomical features through radiography and...
Laminitis is a debilitating disorder resulting in irreversible anatomical changes in the feet of equids. Assessing specific anatomical features through radiography and venography provides diagnostic and prognostic information. The reference ranges are well-established in horses, but not in donkeys. It is also uncertain as to whether these ranges can be applied to every donkey breed. The present study characterizes the radiological and venographic hoof anatomy of healthy feet of Amiata donkeys and defines the changes associated with severe and mild laminitis. A total of 16 forefeet were evaluated in 8 Amiata jennies. The animals underwent musculoskeletal examination, Obel grading assessment and radiological evaluation. Based on clinical examination and radiographic findings, the forefeet were grouped as healthy, mild or severe laminitic feet, thus the digital venograms were performed according to the group definition. Radiology revealed 7/16 healthy, 4/16 mild laminitic, and 5/16 severe laminitic forefeet. Statistical analysis showed differences between the healthy and laminitic forefeet for the dorsal angle ( < 0.0001) and angle of solar aspect ( < 0.0001) of the distal phalanx, for deviation between dorsal aspect of distal phalanx and the hoof wall ( < 0.0001) and phalangeal rotation angle ( = 0.0032). Venography was abnormal in mild and severe laminitic forefeet. In particular, the vascularization was reduced or absent at the lamellar-circumflex junction dorsally, at the sub-lamellar vascular bed and at the circumflex veins. Coronary plexus vascularization was absent in severe laminitic forefeet. This study provides the radiological parameters for the assessment of healthy and laminitic forefeet of Amiata donkeys. The mild laminitic foot venogram showed decreased vascularization mainly on lamellar-circumflex junction and sub-lamellar vascular bed, in latero-medial views. The severe laminitic foot showed very poor or absent vascularization in multiple areas. The technique is easily applicable and provides diagnostic support in laminitis.
PubMed: 33409297
DOI: 10.3389/fvets.2020.601665 -
Journal of Veterinary Internal Medicine Jul 2021The Chihuahua dog breed is known for frequent occurrence of a bregmatic fontanelle on the dorsal skull. A common conception is that this skull defect is a clinically...
BACKGROUND
The Chihuahua dog breed is known for frequent occurrence of a bregmatic fontanelle on the dorsal skull. A common conception is that this skull defect is a clinically irrelevant finding. No studies, however, describe its prevalence or whether it is accompanied by other persistent fontanelles (PFs). Although Chihuahuas are predisposed to Chiari-like malformation (CM) and syringomyelia (SM), it is unknown whether PFs occur more commonly in dogs with clinical signs that are caused by CM or SM.
HYPOTHESIS/OBJECTIVES
To describe the number and location of PFs at cranial sutures (CSs) and to compare the occurrence of these PFs in dogs with and without CM/SM-related clinical signs. We hypothesized that PFs also occur commonly at lateral and caudal cranial surfaces, affect a higher number of CSs, and are larger in dogs with CM/SM-related clinical signs.
ANIMALS
Fifty client-owned Chihuahuas with or without CM/SM-related clinical signs.
RESULTS
Of the 50 dogs evaluated, 46 (92%) had either 1 or several PFs. The mean ± SD number of PFs was 2.8 ± 3.0 (range, 0-13). A total of 138 PFs occupied 118 CSs with 57 (48%) located dorsally, 44 (37%) caudally, and 17 (14%) laterally. The number of CSs affected by PFs was significantly higher (P ≤ .001) and total PF area was significantly larger (P = .003) in dogs with CM/SM-related clinical signs.
CONCLUSIONS AND CLINICAL IMPORTANCE
Persistent fontanelles are very common in this group of Chihuahuas and appear at dorsal, lateral, and caudal cranial surfaces. They are more numerous and larger in Chihuahuas with CM/SM-related clinical signs.
Topics: Animals; Arnold-Chiari Malformation; Dog Diseases; Dogs; Magnetic Resonance Imaging; Skull; Syringomyelia
PubMed: 34028887
DOI: 10.1111/jvim.16151 -
Neuroscience May 1982The agranular insular cortex is transitional in location and structure between the ventrally adjacent olfactory allocortex primutivus and dorsally adjacent sensory-motor...
The agranular insular cortex is transitional in location and structure between the ventrally adjacent olfactory allocortex primutivus and dorsally adjacent sensory-motor isocortex. Its ventral anterior division receives major afferent projections from olfactory areas of the limbic system (posterior primary olfactory cortex, posterolateral cortical amygdaloid nucleus and lateral entorhinal cortex) while its dorsal anterior division does so from non-olfactory limbic areas (lateral and basolateral amygdaloid nuclei). The medial segment of the mediodorsal thalamic nucleus projects to both the ventral and dorsal divisions of the agranular insular cortex, to the former from its anterior portion and to the latter from its posterior portion. Other thalamic inputs to the two divisions arise from the gelatinosus, central medial, rhomboid and parafascicular nuclei. The dorsal division, but not the ventral division, receives input from neurons in the lateral hypothalamus and posterior hypothalamus. The medial frontal cortex projects topographically and bilaterally upon both ventral and dorsal anterior insular cortex, to the former from the ventrally located medial orbital and infralimbic areas, to the latter from the dorsally-located anterior cingulate and medial precentral areas, and to both from the intermediately located prelimbic area. Similarly, the ipsilateral posterior agranular insular cortex and perirhinal cortex project in a topographic manner upon the two divisions of the agranular insular cortex. Commissural input to both divisions originates from pyramidal neurons in the respective contralateral homotopical cortical area. In each case, pyramidal neurons in layer V contribute 90% of this projection and 10% arises from layer III pyramidals. In the brainstem, the dorsal raphe nucleus projects to the ventral and dorsal divisions of the agranular insular cortex and the parabrachial nucleus projects to the dorsal division. Based on their cytoarchitecture, pattern of afferent connections and known functional properties, we consider the ventral and dorsal divisions of the agranular insular cortex to be, respectively, periallocortical and proisocortical portions of the limbic cortex.
Topics: Afferent Pathways; Amygdala; Animals; Cerebral Cortex; Corpus Callosum; Cricetinae; Dominance, Cerebral; Frontal Lobe; Gyrus Cinguli; Horseradish Peroxidase; Hypothalamus; Male; Mesocricetus; Motor Cortex; Neurons; Olfactory Bulb; Somatosensory Cortex; Thalamic Nuclei
PubMed: 7110587
DOI: 10.1016/0306-4522(82)91133-2 -
Cell Adhesion & Migration 2009During development, dorsal root ganglion (DRG) neurons extend their axons toward the dorsolateral part of the spinal cord and enter the spinal cord through the dorsal... (Review)
Review
During development, dorsal root ganglion (DRG) neurons extend their axons toward the dorsolateral part of the spinal cord and enter the spinal cord through the dorsal root entry zone (DREZ). After entering the spinal cord, these axons project into the dorsal mantle layer after a 'waiting period' of a few days. We revealed that the diffusible axonal guidance molecule netrin-1 is a chemorepellent for developing DRG axons. When DRG axons orient themselves toward the DREZ, netrin-1 proteins derived from the ventral spinal cord prevent DRG axons from projecting aberrantly toward the ventral spinal cord and help them to project correctly toward the DREZ. In addition to the ventrally derived netrin-1, the dorsal spinal cord cells adjacent to the DREZ transiently express netrin-1 proteins during the waiting period. This dorsally derived netrin-1 contributes to the correct guidance of DRG axons to prevent them from invading the dorsal spinal cord. In general, there is a complete lack of sensory axonal regeneration after a spinal cord injury, because the dorsal column lesion exerts inhibitory activities toward regenerating axons. Netrin-1 is a novel candidate for a major inhibitor of sensory axonal regeneration in the spinal cord; because its expression level stays unchanged in the lesion site following injury, and adult DRG neurons respond to netrin-1-induced axon repulsion. Although further studies are required to show the involvement of netrin-1 in preventing the regeneration of sensory axons in CNS injury, the manipulation of netrin-1-induced repulsion in the CNS lesion site may be a potent approach for the treatment of human spinal injuries.
Topics: Animals; Axons; Humans; Mice; Nerve Growth Factors; Netrin-1; Regeneration; Signal Transduction; Spinal Cord; Tumor Suppressor Proteins
PubMed: 19262170
DOI: 10.4161/cam.3.2.7837