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PloS One 2024Predating Darwin's theory of evolution, the holotype of Saurodesmus robertsoni is a long-standing enigma. Found at the beginning of 1840s, the specimen is a damaged...
Predating Darwin's theory of evolution, the holotype of Saurodesmus robertsoni is a long-standing enigma. Found at the beginning of 1840s, the specimen is a damaged stylopodial bone over decades variably assigned to turtles, archosaurs, parareptiles, or synapsids, and currently nearly forgotten. We redescribe and re-assess that curious specimen as a femur and consider Saurodesmus robertsoni as a valid taxon of a derived cynodont (?Tritylodontidae). It shares with probainognathians more derived than Prozostrodon a mainly medially oriented lesser trochanter and with the clade reuniting tritylodontids, brasilodontids, and mammaliaforms (but excluding tritheledontids) the presence of a projected femoral head, offset from the long axis of the femoral shaft; a thin, plate-like greater trochanter; a distinct dorsal eminence proximal to the medial (tibial) condyle located close to the level of the long axis of the femoral shaft and almost in the middle of the width of the distal expansion; and a pocket-like fossa proximally to the medial (tibial) condyle. Saurodesmus robertsoni is most similar to tritylodontids, sharing at least with some forms: the relative mediolateral expansion of the proximal and distal regions of the femur, the general shape and development of the greater trochanter, the presence of a faint intertrochanteric crest separating the shallow intertrochanteric and adductor fossae, and the general outline of the distal region as observed dorsally and distally. This makes Saurodesmus robertsoni the first Triassic cynodont from Scotland and, possibly, one of the earliest representatives of tritylodontids and one of the latest non-mammaliaform cynodonts worldwide. Moreover, it highlights the need for revisiting historical problematic specimens, the identification of which could have been previously hampered by the lack of adequate comparative materials in the past.
Topics: Animals; Fossils; Femur; Scotland; Biological Evolution; Phylogeny
PubMed: 38809839
DOI: 10.1371/journal.pone.0303973 -
Cureus Apr 2024Giant cell tumors (GCTs) of the bone present unique challenges in management due to their locally aggressive nature and potential for recurrence. This case report...
Giant cell tumors (GCTs) of the bone present unique challenges in management due to their locally aggressive nature and potential for recurrence. This case report describes the successful surgical management of a GCT located in the proximal tibia of a 28-year-old female. The patient presented with six months of pain and swelling following a traumatic injury to the knee. Diagnostic imaging confirmed the presence of a GCT, leading to preoperative prophylactic embolization to reduce intraoperative bleeding. Surgical excision of the tumor was performed, followed by reconstruction using autologous fibula grafts and plate fixation. Postoperative care included analgesia, antibiotics, and physiotherapy. Regular follow-up demonstrated satisfactory clinical outcomes without evidence of recurrence. This case highlights the importance of a multidisciplinary approach combining surgical expertise, preoperative planning, and postoperative rehabilitation to achieve favorable outcomes in managing GCTs.
PubMed: 38807825
DOI: 10.7759/cureus.59173 -
Schweizer Archiv Fur Tierheilkunde Jun 2024Two six-month old female Lacaune lambs with severe skeletal malformations of both front limbs were presented to the Department of Farm Animals, University of Zurich. The...
Two six-month old female Lacaune lambs with severe skeletal malformations of both front limbs were presented to the Department of Farm Animals, University of Zurich. The clinical examination showed alert animals with a high body weight and body condition score as well as a valgus deformation without pain or swelling. Radiographic examination showed severe irregularities in the epiphysial plate of the metacarpal bones in both lambs. Delayed growth in the lateral aspects of the physis was evident and resulted in valgus deformation. Nutritional causes were considered as the main reason for this presentation and a nutritional consultation was performed by the Institute of Animal Nutrition and Dietetics, University of Zurich. The estimated energy intake of these lambs was 65 % higher than the recommended maximum for growing sheep and the estimated vitamin D content of the diet was 71 % below the recommended allowance. Both animals were euthanized, and peripheral quantitative computed tomography (pQCT) was performed postmortem to measure total bone mineral density (BMD), trabecular bone mineral density (tBMD) and cortical bone mineral density (cBMD) of the left and right metatarsal bone of both animals. The BMD and the tBMD at 10 % of bone length were below the reference values and the BMD at 50 % was above the reference values. In addition, postmortem examination revealed a Salter-Harris-Typ-1 facture in the right caput humeri of one lamb. Histological evaluation showed defects in the articular cartilage with an eburnation in the metacarpal region and a disrupted area of columnar cartilage. This case report supports the fact that a high dietary energy intake leads to damage to the cartilage and the epiphyseal zone in sheep. In addition, insufficient dietary vitamin D intake contributed to the incomplete bone mineralization, as well as delayed growth and skeletal malformation.
Topics: Animals; Female; Sheep; Sheep Diseases; Bone Density; Diet
PubMed: 38807435
DOI: 10.17236/sat00426 -
BMC Musculoskeletal Disorders May 2024To digitally measure the fixation trajectory of anatomical plates used in the combined reduction of quadrilateral acetabular fractures via the posterior approach, and to...
OBJECTIVE
To digitally measure the fixation trajectory of anatomical plates used in the combined reduction of quadrilateral acetabular fractures via the posterior approach, and to develop anatomical plates that align with the characteristics of the pelvis in the Chinese population.
METHODS
Pelvic computed tomography (CT) data from 102 adult patients were collected at the Affiliated Hospital of Zunyi Medical University. This group included 51 males and 51 females, aged between 20 and 60 years. Using Mimics software (version 21.0), a three-dimensional model of each pelvic data point was reconstructed. The fixation path for the combined reset anatomical steel plate was drawn, where the curves on the fixation path were approximated as arcs. The radius of curvature and length of these curves were measured, and an anatomical steel plate was designed to best fit the pelvic structure.
RESULTS
The combined anatomical reduction plate fixation system for quadrilateral acetabular fractures using a posterior approach consisted of two parts: a locking plate and a reduction plate. The posterior wall region (r2), ischial region (r3), quadrilateral region (r4), and bending region (r5), and the total length of the reduction plate were significantly smaller in females (P < 0.05). Similarly, the posterior wall region (R3), distal posterior wall region (R4), and the total length of the locking plate were significantly smaller in females (P < 0.05). Additionally, the anterior superior iliac spine side (r1) and the total length of the T-shaped auxiliary plate were significantly smaller in females (P < 0.05). The bending angle (< A) was also significantly smaller in females (P < 0.05).
CONCLUSIONS
The pelvic surface structure is irregular and varies greatly among individuals.Compared to the traditional steel plate, The combined reduction anatomical plate designed in this study demonstrated high precision and improved conformity to the anatomical structure of the pelvis.
Topics: Humans; Female; Male; Bone Plates; Acetabulum; Adult; Middle Aged; Fracture Fixation, Internal; Fractures, Bone; Young Adult; Tomography, X-Ray Computed; Imaging, Three-Dimensional
PubMed: 38807120
DOI: 10.1186/s12891-024-07522-x -
JOR Spine Jun 2024The first experimental study to produce cervical facet dislocation (CFD) in cadaver specimens captured the vertebral motions and axial forces that are important for...
BACKGROUND
The first experimental study to produce cervical facet dislocation (CFD) in cadaver specimens captured the vertebral motions and axial forces that are important for understanding the injury mechanics. However, these data were not reported in the original manuscript, nor been presented in the limited subsequent studies of experimental CFD. Therefore, the aim of this study was to re-examine the analog data from the first experimental study to determine the local and global spinal motions, and applied axial force, at and preceding CFD.
METHODS
In the original study, quasistatic axial loading was applied to 14 cervical spines by compressing them between two metal plates. Specimens were fixed caudally via a steel spindle positioned within the spinal canal and a bone pin through the inferior-most vertebral body. Global rotation of the occiput was restricted but its anterior translation was unconstrained. The instant of CFD was identified on sagittal cineradiograph films ( = 10), from which global and intervertebral kinematics were also calculated. Corresponding axial force data ( = 6) were extracted, and peak force and force at the instant of injury were determined.
RESULTS
CFD occurred in eight specimens, with an intervertebral flexion angle of 34.8 ± 5.6 degrees, and a 3.1 ± 1.9 mm increase in anterior translation, at the injured level. For seven specimens, CFD was produced at the level of transition from upper neck lordosis to lower neck kyphosis. Five specimens with force data underwent CFD at 545 ± 147 N, preceded by a peak axial force (755 ± 233 N) that appeared to coincide with either fracture or soft tissue failure.
CONCLUSIONS
Re-examining this rich dataset has provided quantitative evidence that small axial compression forces, combined with anterior eccentricity and upper neck extension, can cause flexion and shear in the lower neck, leading to soft tissue rupture and CFD.
PubMed: 38803524
DOI: 10.1002/jsp2.1336 -
Journal of Orthopaedic Surgery and... May 2024The use of continuous passive motion therapy (CPM) has led to promising results in the early phase of rehabilitation after surgical treatment of rotator cuff tears and... (Randomized Controlled Trial)
Randomized Controlled Trial
Early functional improvements using continuous passive motion therapy after angular-stable plate osteosynthesis of proximal humerus fractures - results of a prospective, randomized trial.
BACKGROUND
The use of continuous passive motion therapy (CPM) has led to promising results in the early phase of rehabilitation after surgical treatment of rotator cuff tears and arthrolysis of the elbow. However, its use has not been proven in other pathologies of the upper extremity. Therefore, the aim of the underlying study was to evaluate the use of CPM therapy after plate osteosynthesis of proximal humeral fractures.
METHODS
95 patients with isolated proximal humerus fractures were enrolled in a prospective, randomized study. Patients were assigned to a treatment group with (n = 48, CPM) or without CPM therapy (n = 47, CG). Four patients (2 of each cohort) violated the study protocol and were excluded. CPM therapy was used for 6 weeks after surgery 2-3 times daily. Functional (range of motion) and patient reported outcomes (PROM, Constant Score [CSS], QuickDASH, subjective shoulder value [SSV], pain on visual analogue scale [VAS]) were evaluated at 6 weeks, 3 and 12months. 60 patients completed the 1-year follow-up.
RESULTS
The average patient age was 65.3 years (min: 27, max: 88, SD: ± 14.7). Seventy-two patients were female (79%). There was no difference regarding injury severity (2/3/4 part-fracture: 6/32/7 vs. 9/26/11, p = 0.867) and sex (p = 0.08). However, patients in the CPM group were significantly younger (CPM: 67 [min: 34, max: 82], CG: 74 [min: 27, max: 88], p = 0.032). After 6 weeks we observed a better range of motion for forward flexion (CPM: 90° [min: 50°, max: 180°] vs. CG: 80° [min: 20°, max: 170°] p = 0.035) and abduction (CPM: 80° [min: 40°, max: 180°] vs. CG: 70° [min: 20°, max: 180°], p = 0.048) in the CPM group. There was no difference regarding the further planes of motion or the assessed PROMs at 6 weeks. At 3 and 12 months the results between the treatment groups equalized with no further significant differences.
CONCLUSION
The treatment with CPM increases the range of motion after plate osteosynthesis of proximal humerus fractures in the first 6 weeks after surgery. This effect is not sustained after 3 and 12months. The evaluated PROMs are not being influenced by CPM therapy. Hence the results of this prospective randomized study suggest that CPM can be a beneficial asset in the early period of rehabilitation after proximal humerus plate osteosynthesis.
TRIAL REGISTRATION
The study protocol was registered in the US National Institutes of Health's database ( http://www.
CLINICALTRIALS
gov ) registry under NCT05952622.
Topics: Humans; Middle Aged; Aged; Female; Male; Prospective Studies; Bone Plates; Shoulder Fractures; Fracture Fixation, Internal; Motion Therapy, Continuous Passive; Adult; Aged, 80 and over; Range of Motion, Articular; Treatment Outcome; Recovery of Function; Time Factors; Follow-Up Studies
PubMed: 38802866
DOI: 10.1186/s13018-024-04804-x -
Plastic and Reconstructive Surgery.... May 2024Acute cervical osteomyelitis due to an epidural abscess and pyogenic spondylodiscitis in an immunosuppressed patient with progressive myelopathy is a challenge for the...
Acute cervical osteomyelitis due to an epidural abscess and pyogenic spondylodiscitis in an immunosuppressed patient with progressive myelopathy is a challenge for the reconstructive surgeon. This report presents our novel approach to treat such a condition in a 56-year-old patient in whom antibiotic treatment and decompression of the medulla by laminectomy of C4-C6 failed. Under general anesthesia, debridement of all infected tissue, including anterior corpectomy of C4-C6, was performed. Simultaneously, a free vascularized fibula graft (FVFG) was harvested, adapted to the bone defect, and anastomosed to the superior thyroid artery and external jugular vein. The graft was stabilized with an anterior plate. A scheduled posterior stabilization was performed 1 week later. was cultured from bone samples and was treated with antibiotics. The postoperative course was uncomplicated besides a dorsal midline defect 6 weeks postoperatively that was closed with a sensate midline-based perforator flap. Five years on, the patient is infection free, and regular control computed tomography and magnetic resonance imaging scan images show progressive fusion and hypertrophy of the fibula to C3/C7 vertebrae. An FVFG combined with posterior stabilization could be a promising primary salvage procedure in cases with progressive myelopathy caused by acute cervical osteomyelitis due to spinal infection. The FVFG contributes to blood circulation, delivery of antibiotics, and an immunological response to the infected wound bed and can stimulate rapid fusion and hypertrophy over time.
PubMed: 38798940
DOI: 10.1097/GOX.0000000000005837 -
Narra J Apr 2024Bone implants are important in the recovery of fractures and degenerative diseases. Although many implants have been marketed, study on Indonesian-made plates is still... (Comparative Study)
Comparative Study
Bone implants are important in the recovery of fractures and degenerative diseases. Although many implants have been marketed, study on Indonesian-made plates is still limited. The aim of this study was to assess the patients' functional and radiological improvements and biomechanical and chemical changes of Indonesian-made plates used in long bone fractures. retrospective study was conducted at Semen Gresik Hospital, Gresik, Indonesia. This study included adult patients with long bone fractures who had surgeries with Indonesian plates. Functional improvement (assessed using disabilities of arm, shoulder, and hand (DASH) or lower extremity functional scale (LEFS)) and radiological data (assessed using radiographic union score (RUS)) were assessed in week 4 and month 6, 12, and 15 after surgery. Biomechanical changes (hardness and roughness test) and chemical analysis were assessed after 15 months of use. The normality of the data was tested with Shapiro-Wilk while data analysis was conducted using paired Student t-test or Friedman test as appropriate with type of data. Our data indicated that the DASH and LEFS functional scores had significant improvement over the follow-ups indicating functional recovery. RUS scores also improved over time, indicating a good healing process. Hardness tests on post-surgery implants showed a decrease in hardness of 7.3% and an increase of 3.3% in roughness. Chemical analysis showed a reduction in chemical levels in the implant of 7.8%, indicating durability and minimal toxicity. This study highlights that Indonesian implants have been proven safe to use in fractures. Further examinations with a larger sample and a longer duration of monitoring are recommended for stronger validity.
Topics: Humans; Male; Indonesia; Bone Plates; Retrospective Studies; Female; Adult; Fractures, Bone; Middle Aged; Biomechanical Phenomena; Fracture Fixation, Internal; Radiography; Recovery of Function; Aged
PubMed: 38798872
DOI: 10.52225/narra.v4i1.752 -
Progress in Orthodontics May 2024Skeletal anterior open bite (SAOB) represents one of the most complex and challenging malocclusions in orthodontics. Orthodontic treatment supported by miniplates enable...
BACKGROUND
Skeletal anterior open bite (SAOB) represents one of the most complex and challenging malocclusions in orthodontics. Orthodontic treatment supported by miniplates enable to reduce the need for orthognathic surgery. Transverse dimension may be affected by intrusion biomechanics. This study aims to assess transverse bone alterations in patients with SAOB who underwent orthodontic treatment with absolute anchorage using four miniplates.
METHODS
A total of 32 patients of both sexes, with an average age of 33.8 years, diagnosed with SAOB and treated orthodontically with four miniplates (one in each hemiarch), were selected for this study. Tomographic examinations were performed before (T1) and after (T2) orthodontic treatment. Linear measurements (width of the maxillary base, maxillary alveolar, maxillary root, maxillary dental cusp, mandibular alveolar) and angular measurements (maxillary intermolar angle) were assessed in these images. The Shapiro-Wilks normality tests were applied to verify data distribution, and the paired t-test was used to compare the initial and final measures obtained.
RESULTS
Among the evaluated parameters, the maxillary alveolar width, maxillary dental cusp width, mandibular alveolar cusp width, and intermolar angle showed statistically significant differences between T1 and T2 (p < 0.05). However, maxillary base and maxillary root widths showed no significant difference (p > 0.05).
CONCLUSIONS
Intrusion and distalization with miniplates in SAOB therapy may lead to significant expansive changes, due to molars cusps width and buccal inclination increase restricted at the alveolar level.
Topics: Humans; Orthodontic Anchorage Procedures; Male; Female; Open Bite; Adult; Bone Plates; Mandible; Maxilla; Cephalometry; Alveolar Process; Tooth Movement Techniques; Tomography, X-Ray Computed; Young Adult; Orthodontic Appliance Design
PubMed: 38797777
DOI: 10.1186/s40510-024-00519-1 -
Polymers May 2024The aim of this study was to evaluate the effect of two different insertion speeds at eight different insertion torque values ranging from 25 to 60 during implantation...
The aim of this study was to evaluate the effect of two different insertion speeds at eight different insertion torque values ranging from 25 to 60 during implantation in a dense polyurethane (PU) D1 bone model on the placement condition and removal torque of dental implants. In this study, 50 pcf single-layer PU plates were used. In the study, a total of 320 implant sockets were divided into two groups, Group 1 (30 rpm) and Group 2 (50 rpm), in terms of insertion speed. Group 1 and Group 2 were divided into eight subgroups with 25, 30, 35, 40, 45, 50, 55 and 60 torques. There were 20 implant sockets in each subgroup. During the implantations, the implant placement condition and removal torque values were assessed. There was a statistically significant difference between the 30 and 50 rpm groups in terms of overall implant placement condition ( < 0.01). It was found that the removal torque values at 50 rpm were statistically significantly higher than those at 30 rpm ( < 0.01). This study showed that in dense D1 bone, the minimum parameters at which all implants could be placed at the bone level were 50 torque at 30 rpm and 40 torque at 50 rpm.
PubMed: 38794554
DOI: 10.3390/polym16101361