Osseous Abnormalities Research Articles

Diagnostic Imaging of Ulnar Collateral Ligament Injury: A Systematic Review

Background: Ulnar collateral ligament (UCL) injuries can be debilitating in overhead athletes. Accurate diagnosis is important; however, several imaging modalities are available for the assessment of UCL injuries. Purpose: To provide a comprehensive review of published literature regarding the diagnostic capabilities of different imaging modalities for UCL tears. Methods: PubMed, Medline, and Embase were queried for peer-reviewed literature published between January 1947 and June 4, 2019, pertaining to diagnostic imaging of UCL tears. Articles assessing static and stress radiography, ultrasound, magnetic resonance imaging (MRI), MRI with arthrography (MRA), and computed tomography arthrography of the UCL were included. Studies were excluded if imaging results were not compared with intraoperative diagnosis, as intraoperative findings are generally considered the gold standard for diagnostic comparison. The articles were assessed per the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines and reviewed with the Quality Assessment of Diagnostic Accuracy Studies, version 2 (QUADAS-2) assessment. Results: The literature search yielded 2478 articles, of which 15 were included in this review. Potential bias was noted in each QUADAS-2 subsection. Multiple studies demonstrate an association between UCL tears and osseous abnormalities identified on static radiographs; however, the use of static or nonstressed radiographs is not recommended for specific evaluation of UCL injuries. Conventional ultrasound was 81% sensitive and 91% specific, as compared with 96% and 81% for stress ultrasound, respectively. The sensitivity and specificity of MRI ranged from 57% to 100% and 89% to 100%. The sensitivity of computed tomography arthrography ranged from 63% to 86%. The sensitivity and specificity of MRA ranged from 81% to 100% and 91% to 100%. Conclusion: Of the currently available imaging modalities, MRA provides the best combination of sensitivity and specificity of the evaluation of the UCL. Further research comparing ultrasound with MRA is needed.

Role of Phosphate in Biomineralization.

Inorganic phosphate is a vital constituent of cells and cell membranes, body fluids, and hard tissues. It is a major intracellular divalent anion, participates in many genetic, energy and intermediary metabolic pathways, and is important for bone health. Although we usually think of phosphate mostly in terms of its level in the serum, it is needed for many biological and structural functions of the body. Availability of adequate calcium and inorganic phosphate in the right proportions at the right place is essential for proper acquisition, biomineralization, and maintenance of mass and strength of the skeleton. The three specialized mineralized tissues, bones, teeth, and ossicles, differ from all other tissues in the human body because of their unique ability to mineralize, and the degree and process of mineralization in these tissues also differ to suit the specific functions: locomotion, chewing, and hearing, respectively. Biomineralization is a dynamic, complex, and lifelong process by which precipitations of inorganic calcium and inorganic phosphate divalent ions form biological hard tissues. Understanding the biomineralization process is important for the management of diseases caused by both defective and abnormal mineralization. Hypophosphatemia results in mineralization defects and osteomalacia, and hyperphosphatemia is implicated in abnormal excess calcification and/or ossification, but the exact mechanisms underlying these processes are not fully understood. In this review, we summarize available evidence on the role of phosphate in biomineralization. Other manuscripts in this issue of the journal deal with other relevant aspects of phosphate homeostasis, phosphate signaling and sensing, and disorders resulting from hypo- and hyperphosphatemic states.

HIP INJURY- CROSS COUNTRY

HISTORY 18-year-old high school female cross-country runner presented with one week of left anterior hip pain. Denied a specific injury. Pain started during a late season meet causing her to finish at a slower pace. Pain progressively worsened requiring crutches to ambulate, despite no further activity. Max mileage was 40 miles/week, had tapered to 20 miles/week prior to injury. History of stress fracture 4 years prior. Initial x-ray of left hip revealed open epiphyseal plates, no other osseous abnormalities. Inquiring about menstrual history, she had yet to reach menarche. Per the patient’s mother, she had been trialed on growth hormone and is currently on estradiol patches. She has a known eating disorder for which she is not actively receiving help, despite multiple hospitalizations. PMHX Primary amenorrhea, followed by endocrinology. Lab work revealed low estradiol, LH, FSH with high alkaline phosphatase. Normal labs were thyroid studies, BMP, LFT, vitamin D and prolactin. Genetics showed 46XX. Multiple XR for bone age showed that of an 11-year-old. Cardiac work up showed sinus bradycardia on EKG and normal echo. Brain/pituitary MRI revealed normal pituitary and mild enlargement of ventricles, sulci, cerebellar folia. PHYSICAL EXAMINATION Patient stands 55 inches tall, weighing 61 pounds with a BMI of 14. She appears much younger than stated age. Hair is full, though fine. Breast tissue is not appreciated. On left hip exam, there is TTP along flexor tendon, lateral hip, and piriformis. She has pain with external rotation, weakness and pain with hip flexion, abduction, and adduction against resistance. She is unable to do a single leg hop due to groin pain. She is neurovascularly intact. DIFFERENTIAL DIAGNOSIS 1. Femoral neck stress fracture 2. Primary amenorrhea 3. Hip flexor strain 4. Relative Energy Deficiency in Sports syndrome 5. ASIS avulsion fracture TESTS/RESULTS MRI left hip 1. Partial thickness tear at attachment of left iliopsoas tendon to lesser trochanter with intramuscular hematoma 2. Minimal partial thickness tear of the left common hamstring origin FINAL DIAGNOSIS 1. Partial tear of left iliopsoas tendon and hamstring 2. RED-S TREATMENT/OUTCOMES 1. Shut down from all activities 2. Weightbearing as tolerated 3. Referral to gynecology for transvaginal ultrasound 4. Referral to Eating Recovery Center

Neck Injury - Football

HISTORY: 21-year-old senior high school football offensive line men sustained a neck injury while tackling. During the third quarter of a midseason game, he tackled an opponent player, and they both landed on the ground. The patient was facing down with opposing player just underneath his anterior torso. Shortly after the play, given he was near the ball, a pile up of players landed on his upper back. He sustained a hyperextension injury of his cervical neck since his head was laying on the player he tackled. Patient described an immediate "pop" sensation in his neck and had "complete weakness & numbness" of his R upper & lower extremities. PHYSICAL EXAMINATION: After safely placing patient in supine position on spine board, examination demonstrated he as alert and orientated x 4, had spinous process tenderness from C4-C7. Sensory testing along both extremities revealed significantly decreased and almost absent sensation in R upper & lower extremity. He was unable to raise / move his R arm or leg. His distal pulses and breathing were within normal ranges. DIFFERENTIAL DIAGNOSIS: Cervical Cord Compression, Cervical Fracture, Cervical Disc Herniation, Cervical Facet Radiculopathy, TESTS AND RESULTS: Cervical XRAYS: No osseous abnormality. Cervical CT Scan: L neural foramina stenosis at C3/C4, R neural foramina stenosis at C6/7. Mild to moderate spinal canal stenosis at C6/7 and C7/T1. Thoracic CT Scan: Normal CT chest, abdomen, pelvic, and thoracic spine. MRI Cervical Spine: C6-7 where a right paracentral / foramina disc protrusion. Mild central canal stenosis at T1-2 level due to diffuse disc bulge. FINAL/WORKING DIAGNOSIS: C6-7 cervical disc herniation with mild to moderate cervical cord stenosis at C6/7 and T1-2. TREATMENT AND OUTCOMES: R-sided weakness resolved after 4 weeks of supportive care, watchful waiting and physical therapy.

RESEARCH ON THE STRATEGY OF REDUCTION OPERATION OF BASILAR INVAGINATION COMBINED WITH ATLANTOAXIAL DISLOCATION

Background: The complicated basilar invagination and atlantoaxial dislocation (BI-AAD) can cause a variety of neurological symptoms. Active treatment should be given. The main method of surgical treatment is to relieve the compression of the ventral bone of the brain stem and to fix the unstable spinal segments for fusion. At present, more surgical methods choose modified posterior cervical reduction and internal fixation fusion. Objective: The clinician has preliminarily designed an internal occipital fixation system capable of restoring both horizontal and vertical AADs, and proposed a new compression and distraction reduction (CDR) technique. The feasibility and effectiveness of posterior AAD reduction surgery using CDR techniques for different types of patients were studied in this paper. Methods: First, according to the CT scan sequence images of the congenital BI-AAD patient’s cervical vertebra, the software Materialize Mimics 13.1 was imported to reconstruct 3D geometric model of cervical spine (C0-C7). Then the geometric topology model was carried out in Geomagic2012 software, and surrounding soft tissue was established using SpaceClaim 14.0. The 3D finite element model (FEM) of cervical vertebra for congenital BI-AAD patients was obtained by assigning material attributes, setting contacts and mesh in ANSYS 14.0. To simulate the physiological activities of the spine under two conditions of forward flexion and backward extension, preoperative verification was carried out with the maximum displacement parameter. According to the postoperative CT data of the patient, the position and degree of freedom (DOF) of the occipitocervical internal fixation system were determined. The FEM of the occipitocervical internal fixation system was established by dividing unit grid in ANSYS. Using multiple loading step of statics analysis method, the CDR technology of posterior AAD reduction surgery was simulated. When the atlantoaxial horizontal and vertical reductions were satisfactory, the displacement data were obtained and verified using the post-operative data. Results: The cervical spine (C0-C7) FEM of congenital BI-AAD patients was established. For some lateral atlantoaxial articulation abnormal ossification II, we simulated the CDR technique for the AAD reduction surgery and proposed using the vertical traction instead of vertical reduction. Conclusion: This study confirms the feasibility and effectiveness of posterior AAD reduction surgery using CDR techniques and proposes the different reduction optimization scheme for the patients with lateral atlantoaxial articulation abnormal ossification II of congenital BI-AAD. The results of this study provide a biomechanical theoretical basis for improving the reliability of simple posterior reduction surgery and optimizing the surgical treatment of BI-AAD.

Hip morphology in mucopolysaccharidosis type IVA through radiograph, magnetic resonance imaging and arthrogram assessment

This study examined the hip morphology of paediatric patients with mucopolysaccharidosis (MPS) type IVA (MPS IVA). This was a retrospective chart review of 42 hips in 21 children with MPS IVA. Pelvic radiographs and magnetic resonance imaging (MRI) scans of 42 hips and arthrograms of 13 hips were analysed. The bony, cartilaginous and labral coverage of the acetabulum was determined by acetabular index (AI), centre edge angle (CEA) and femoral head coverage (FHC). The mean age at the time of radiography was 66.3 ± 21.7months. The bony, cartilaginous and labral AI in the MRI assessment were 36.3 ± 5.3, 18.3 ± 4.7 and 12.1 ± 4.6 degrees, respectively. The inter-class correlation coefficients (ICCs) for the bony AI, CEA and FHC measurements on radiographs and MRI were 0.936, 0.879 and 0.810, respectively. In the MRI assessment, labrum in 12 of 42 hips appeared as a regular triangle, and it was flat on 30/42 hips. The average arthrographic AI (AAI) was 11.1 ± 2.7 degrees. The ICCs value of AAI versus cartilaginous and labral AI on MRI indicates good agreement but higher in labral AI. Hips in MPS IVA exhibited obvious cartilage and labrum compensation in response to abnormal ossification of bony acetabulum. Cartilage in MPS IVA hip increases the thickness in the longitudinal direction, while the labrum becomes flatten in the horizontal direction. The AAI may represent intraoperative labrum coverage. The femora-acetabular harmony is difficult to determine using radiography only, and pre-operative MRI and an intraoperative arthrogram are very important in a hip assessment in MPS IVA.

Cervical Abnormalities in Severe Spinal Deformity: A 10-year MRI Review.

ObjectiveTo investigate the incidence of cervical anomalies (CA), including cervical intraspinal neural axis abnormalities (CIINAA) and/or cervical osseous abnormalities (COA), and the clinical relevance in severe spinal deformities (SSD) at a single center.MethodsA retrospective study of SSD admitted for spinal surgery from January 2003 to January 2015 was conducted at a single center. Inclusion criteria: patients who present with coronal Cobb over 90° (and/or sagittal cobb ≥90°); and patients with complete imaging and clinical data preoperatively. Exclusion criteria: ankylosing spondylitis, adult onset scoliosis, scoliosis secondary to bone destruction. There were 108 SSD patients who fulfilled the criteria in this research (41 males and 67 females). The mean age of the patients was 18.1 ± 2.7 years (range, 10–45 years). The clinical and radiological data of these patients were reviewed to identify CA and to analyze the relationship between clinical and radiographic characteristics in the population of SSD.ResultsThe major curves of scoliosis and segmental kyphosis were 109.1° ± 24.7° and 91.2° ± 29.1°. Cervical abnormalities were detected in 56 patients (51.85%) with 9 different CA, including 28 patients (25.9%) with 6 different COA, 21 patients (19.4%) with 3 different CIINAA, and 7 patients (6.5%) with a combination of COA and cervical intraspinal neural axis abnormalities (CINAA). Basilar invagination and Klippel–Feil syndrome were the most frequent COA. Syringomyelia was the most frequent CINAA. SSD with COA in upper vertebral levels (UVL) had a higher incidence of CINAA than those in subaxial vertebral levels (SVL) (P = 0.024) and SSD with multiple COA (mCOA) in UVL had a higher incidence of CINAA than those with single COA (sCOA) (P = 0.029). In the present study, 83.9% of the SSD with CA were asymptomatic.ConclusionThe incidence of CA in SSD was 51.85%, with most presenting with intact neurologic status. As the diversity of COA increased, we found a higher incidence of CINAA, especially in UVL.

Gestational and early postnatal exposure to a mixture of organophosphate ester flame retardants found in Canadian house dust on hindlimb skeletal development in postnatal day 4 rats

Background: Ever since organophosphate esters (OPEs) became the mainstream replacement for organobromine compounds in fire retardants (FRs), numerous studies have explored their potential as endocrine disruptors and developmental toxicants. The purpose of this study is to investigate the impact of gestational and early postnatal exposure of OPE mixtures on the ossification of hindlimb phalangeal in postnatal day 4 (PND4) rat pups, as the amount of OPEs within the diet mixture is relative to its composition in Canadian household dust.Methods: Male and female adult Charles River Sprague-Dawley rats were exposed to OPE mixtures for 70 and 21 days, respectively. The OPE doses were determined to be 10x, 1,000x, and 30,000x the relative human exposure. The progenies were exposed to OPEs both gestationally (~21 days) and lactationally (4 days). At least 2 of each sex from each litter were sacrificed and processed at PND4 for skeletal staining using Alizarin red and Alcian blue. The samples were analyzed and compared against a reference sample to examine any abnormalities in ossification.Results: At PND4, there is no significant effect of OPEs on the number of pups with abnormal ossification between the control and treatment groups. High doses of OPEs, at concentrations 30,000x of relative human exposures, showed a significant increase in the severity of delay of ossification at the middle phalanx of PND4 pups.Limitations: Due to the limitation of small sample sizes (litter n=6-7) and a wide variance in data, there is no clear evidence on whether OPE exposure induces greater incidences of abnormal ossification in the digits of PND4 pups.Conclusion: There is a delay in ossification from OPE exposure at the high dose (30,000x).

Analysis of Ossification Abnormalities and Gene Expression in CCI Rats, a New Animal Model of Dwarfism

Analysis of Ossification Abnormalities and Gene Expression in CCI Rats, a New Animal Model of Dwarfism

Distribution of diffuse plexiform neurofibroma on the body surface in patients with neurofibromatosis 1.

Neurofibromatosis 1 (NF1) is a genetic disease characterized by cutaneous, neurological and osseous abnormalities. Approximately 20% of patients develop plexiform neurofibroma (PN), resulting in impaired quality of life. To evaluate distribution of diffuse PN on the body surface, a retrospective study was conducted for 354 patients with NF1 from 2007 to 2018 in Japan. We investigated a total of 40 patients with clinically apparent superficial diffuse PN. In the cases evaluated, 57.4% of the diffuse PN were located on the trunk, 19.2% the head and neck, 12.8% the lower limbs and 10.6% the upper limbs. Remarkably, 75.0% of the diffuse PN were located on the dorsal side. The frequency was significantly higher on the trunk than on the head and neck (P=0.026). Our findings provide useful information for giving attention to the high possibility of diffuse PN on the dorsal side before progression in childhood and for future treatment in NF1.

Imaging of osteochondrosis.

Osteochondrosis is an abnormality of the epiphyses or epiphyseal equivalents (round bones and apophyses) during later stages of endochondral ossification. This process of abnormal endochondral ossification can occur at various locations throughout the body. The pathogenesis of osteochondrosis is under active investigation. In humans, the process of abnormal endochondral ossification has been attributed to a combination of vascular insult and trauma. Although the proposed etiology of osteochondrosis varies based on body part affected, the overall process is defined by necrosis, revascularization and repair. As such, common radiologic findings include those of osseous destruction and associated inflammation. The purpose of this review is to discuss the current understanding of osteochondroses as a disease entity and explore imaging features of osteochondroses throughout the body.

Impingement syndromes of the ankle and hindfoot.

Ankle impingement refers to a chronic painful mechanical limitation of ankle motion caused by soft-tissue or osseous abnormality affecting the tibiotalar joint or extraarticular soft tissues. Impingement can be associated with a prior single traumatic event or repetitive microtrauma, often in an adolescent with anatomical predisposition. Impingement syndromes at the tibiotalar joint can be subdivided into anterior, anterolateral, anteromedial, posterior or posteromedial. Extraarticular impingement can consist of talocalcaneal or subfibular impingement. Impingement syndromes are just one possible etiology of persistent ankle pain, and although the diagnosis is often made or suspected clinically, the radiologist might be the first person to raise the possibility of the diagnosis or be called upon to provide support for the clinically suspected diagnosis. In this article I review the etiology, imaging findings and current treatment associated with these conditions.

Evaluation of Osseous Morphology of the Hip Using Zero Echo Time Magnetic Resonance Imaging

Background: Femoroacetabular impingement syndrome (FAIS) is a common disorder of the hip resulting in groin pain and ultimately osteoarthritis. Radiologic assessment of FAI morphologies, which may present with overlapping radiologic features of hip dysplasia, often requires the use of computed tomography (CT) for evaluation of osseous abnormality, owing to the difficulty of direct visualization of cortical and subchondral bone with conventional magnetic resonance imaging (MRI). The use of a zero echo time (ZTE) MRI pulse sequence may obviate the need for CT by rendering bone directly from MRI. Purpose/Hypothesis: The purpose was to explore the application of ZTE MRI to the assessment of osseous FAI and dysplasia morphologies of the hip. It was hypothesized that angular measurements from ZTE images would show significant agreement with measurements obtained from CT images. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: Thirty-eight hips from 23 patients were imaged with ZTE MRI and CT. Clinically relevant angular measurements of hip morphology were made in both modalities and compared to assess agreement. Measurements included coronal and sagittal center-edge angles, femoral neck-shaft angle, acetabular version (at 1-, 2-, and 3-o’clock positions), Tönnis angle, alpha angle, and modified-beta angle. Interrater agreement was assessed for a subset of 10 hips by 2 raters. Intermodal agreement was assessed on the complete cohort and a single rater. Results: Interrater agreement was demonstrated in both CT and ZTE, with intraclass correlation coefficient values ranging from 0.636 to 0.990 for ZTE and 0.747 to 0.983 for CT, indicating “good” to “excellent” agreement. Intermodal agreement was also shown to be significant, with intraclass correlation coefficients ranging from 0.618 to 0.904. Conclusion: Significant agreement of angular measurements for hip morphology exists between ZTE MRI and CT imaging. ZTE MRI may be an effective method to quantitatively evaluate osseous hip morphology.

Total Hip Arthroplasty in Patient with Melorheostosis (Case Report)

Melorheostosis is a rare mesenchymal dysplasia of bone manifesting as regions of sclerosing and thickening of bone tissue. This disease may involve the adjacent soft tissues and lead to joint pain, limitation of joint motion, stiffness resulting from abnormal ossification and soft-tissue contractures due to periarticular fibrosis. The paper describes a clinical case of a patient who presented with pain and stiffness in the proximal part of the left hip which patient suffered for the last 10 years. At first the patient had intermittent pain in the lower back and left hip during and after walking. Radiographs revealed dense sclerotic and wavy cortex and hyperostosis involving the left iliac crest, the acetabulum, and the femur. CT angiography with contrast was performed for preoperative planning. During the procedure the authors performed total hip arthroplasty of the left hip with excision of fibro-ossifications in the left ilioinguinal area. Severe periarticular fibrosis of the soft tissue was observed intraoperatively and cartilage-like formation was visible around the joint. A sample of the ossification bone was resected for histologic confirmation of the diagnosis; extensive cortical sclerosis with varying thickness typical of melorheostosis was found. Early postoperative period went without complications following routine post-THR protocol. Postoperative X-rays at 6, 12, 24 months did not reveal any complications or new ossifications. Full ROM and pain-free function were achieved in the left hip and lower back of the patient. The present clinical case of total hip arthroplasty with excision of fibroossifications provided good clinical outcome for melorheostosis of the left hip.

Reduction of the atlantoaxial dislocation associated with basilar invagination through single-stage posterior approach: using Xuanwu occipital-cervical reduction surgical suite

Objective: To examine the effect of posterior reduction in atlantoaxial dislocation (AAD) associated with basilar invagination(BI) using Xuanwu occipital-cervical fusion system in single stage. Methods: Thirty-seven AAD accompanied with BI cases treated at Department of Neurosurgery, Xuanwu Hospital, Capital Medical Universiy and the Second Hospital of Hebei Medical University were retrospective analyzed. There were 15 males and 22 females with age of (42.3±12.3)years (range: 18-69 yars). All the cases had congenital osseous abnormalities, such as assimilation of atlas and abnormal cervical fusion. Anterior tissue was released through posterior route followed by cage implantation into facet joint and occipital-cervical fixation with cantilever technique. The clinical results were evaluated using Japanese Orthopedic Association scale(JOA) and the main radiological measurements including anterior atlantodental interval (ADI),the distance of odontoid tip above Chamberlain line,clivus-canal angle (CCA) and the length of syrinx were collected.The preoperative and postoperative JOA score and radiological measurements were compared by paired t-test. Results: The mean JOA score of the patients increased from 10.5 to 14.4 at the one-year follow-up(t=14.3,P=0.00).Complete reduction of AAD and BI was achieved in 34 patients.The mean clivus-canal angle improved from 118.0 degrees preoperative to 143.7 degrees postoperative(t=6.2,P=0.00). Shrinkage of the syrinx was observed 1 week after surgery in 24 patients, and 6 months in 31 patients. Twenty-eight patients achieved bone fusion 6 months after surgery. All the patients achieved bone fusion 12 months after surgery. One-side vertebral artery occlusion was diagnosed in 1 case postoperatively for transient dizziness, and relieved in 2 weeks. Two patients developed moderate neck pain after surgery, and relieved in 1 month. No implant failure, spacer subsidence or infection was observed. Conclusions: The treatment of AAD associated with BI using Xuanwu occipital-cervical fusion system from posterior approach in single stage is effective and safe. Cage implantation intraarticularly and fixation with cantilever technique achieve complete reduction in most cases.

SMFM Fetal Anomalies Consult Series #2: Extremities

SMFM Fetal Anomalies Consult Series #2: Extremities

Management of the First Patellar Dislocation: A Narrative Review.

First patellar dislocation is a common injury of the knee, involving often adolescents and the active population. The consequences of the first episode can be various and potentially disabling. Among these, acute patellar dislocation can often result in recurrent patellar instability. Recurrent patellar instability is certainly multifactorial but depends primarily on the injury of the medial patellofemoral ligament (MPFL), the major soft-tissue stabilizer of the patella. Some classifications are extremely useful in establishing the diagnosis and therapy in patellofemoral disease, in particular in terms of instability. Among those, Henri Dejour and WARPS (weak atraumatic risky anatomy pain and subluxation)/STAID (strong traumatic anatomy normal instability and dislocation) classifications are certainly the most frequently used. There is no clear agreement on the management of the first patellar dislocation. A conservative approach seems to be the first choice in most of cases, but the presence of patellar displacement or osteochondral fractures makes surgery mandatory at the beginning. In addition, there is no clear consensus on which surgical strategy should be used to approach first dislocation, in relation to the possible variation in location of the MPFL injury, and to the eventual presence of preexisting predisposing factors for patellar instability. MPFL reconstruction may theoretically be more reliable than repair, while there is no clear evidence available that osseous abnormality should be addressed after the first episode of patellar dislocation. A narrative review was conducted to report the etiology, the diagnosis and all the possible treatment options of the first patellar dislocation. Modern classifications of the patellofemoral instability were also presented.

Preoperative imaging of traumatic anterior shoulder instability: Diagnostic effectiveness of magnetic resonance arthrography and comparison with conventional magnetic resonance imaging and arthroscopy

Background: Associated injuries of traumatic anterior shoulder dislocations play an important role in predicting recurrent instability. MRI has proved popular for imaging of suspected abnormalities. MR arthrography (MRA) has been suggested to be more sensitive than MRI in the detection of labral tears and other capsular lesions. In this study, we aimed to assess prospectively the diagnostic effectiveness of MRA in the preoperative planning of traumatic anterior shoulder instability compared with conventional MRI and arthroscopy. Methods: Shoulder MRI and MRA in 100 patients (73 men and 27 women; mean age, 27 yr) with shoulder dislocations were evaluated by two musculoskeletal radiologists who were blinded to arthroscopic findings, which represented the reference standard. An arthroscopic surgeon blinded to the imaging findings evaluated the osseous abnormalities involving the humeral head and glenoid, anterior labroligamentous lesions, and capsular lesions. Sensitivity, specificity, accuracy, and positive and negative predictive values of each imaging study were calculated for each elemental lesion and compared using a paired McNemar test. Results: When comparing the sensitivity and accuracy values of the MRA and MRI for the detection of these elemental lesions, all values of MRA were higher than those of MRI (P<0.01). However, when comparing the specificity values, both MRI and MRA were highly specific (100%) in diagnosing bony Bankart lesions and anterior labroligamentous periosteal sleeve avulsions. MRI missed Perthes lesions, humeral avulsions of the anterior glenohumeral ligament, and glenoid avulsions of the anterior glenohumeral ligament. Conclusions: Despite being invasive, MRA is considerably more useful in the identification and categorization of different elemental lesions of traumatic chronic anterior shoulder instability.

P107. Releasing anterior soft tissue and reduction of the irreducible atlantoaxial dislocation associated with basilar invagination through single-stage posterior approach

BACKGROUND CONTEXT The management of AAD combined with BI is challenging. Traditional posterior approaches lack the ability to release the anterior soft tissue and result in unsatisfactory reduction; posterior fixation followed by the anterior release approach has higher morbidity and lead to higher costs and a longer length of stay. PURPOSE This study aims to analyze outcomes of the release of anterior soft tissue through posterior route in order to reduce irreducible atlantoaxial dislocation (AAD) and basilar invagination (BI) through a single-stage operation. This study aims to analyze outcomes of the release of anterior soft tissue through posterior route in order to reduce irreducible atlantoaxial dislocation (AAD) and basilar invagination (BI) through a single-stage operation. STUDY DESIGN/SETTING This is a retrospective study. PATIENT SAMPLE Thirty-one patients with irreducible AAD and concomitant BI with congenital osseous abnormalities were analyzed. OUTCOME MEASURES The clinical results were evaluated using the Japanese Orthopedic Association (JOA) scale, and the radiological measurements included anterior atlantodental interval (ADI), the distance of odontoid tip above Chamberlain line, clivus-canal angle (CCA) and the length of the syrinx. METHODS The anterior soft tissue was released posteriorly, and cages were placed into the facet joint followed by occipital-cervical fixation with cantilever correction. We used paired t-test to compare preoperative and postoperative measurements. RESULTS The mean JOA score increased from 11.65 to 14.48 at 1-year follow-up. Complete reduction of AAD and BI was achieved in 23 patients (74.2%). The mean clivus-canal angle improved from 113.0 degrees preoperatively to 148.4 degrees postoperatively. Shrinkage of the syrinx was observed in 6 patients in one week after surgery. Nine patients had 18-month follow-up and achieved bone fusion. Twenty-two patients have a 12-month follow-up, and 19 (86.3%) achieved bony fusion. Unilateral vertebral artery occlusion was diagnosed in 2 cases without clinical symptoms. CONCLUSIONS It appears effective and safe to treat irreducible AAD associated with BI by releasing the anterior soft tissue from a posterior approach. Cage implantation within the facet and fixation using cantilever can achieve complete reduction in most cases. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Extensive ossification of the ungular cartilages and other osseous abnormalities of the proximal and distal phalanges

SummaryOssification of the ungular cartilages of the equine foot has been well documented. There is growing evidence to suggest that extensively ossified cartilages (≥grade 4) can be associated with injury, pain and lameness. The objectives of this study were to describe the locations and extent of new bone on the proximal and distal phalanges and to determine the frequency of occurrence related to the ossification grade of the ungular cartilages. It was hypothesised that new bone formation would be seen more commonly in horses with grades ≥4 ossification than those with ossification of grade ≤3. Data were collected from 929 sets of images from individual limbs of 589 horses. Logistic regression modelling was used to indicate predictor variables that were significant. In 15.4% of limbs, there was grade 4 or 5 ossification of one or both ungular cartilages. New bone formation was seen on the palmaromedial and palmarolateral aspects of the diaphyseal and distal metaphyseal regions of the proximal phalanx in 28.7% of limbs. New bone formation was seen on the dorsal, dorsomedial and dorsolateral aspects of the distal phalanx, midway between proximal and distal in 7.2% of limbs. New bone formation was seen more commonly on the proximal phalanx (P≤0.002) and the distal phalanx (P≤0.042) in feet with grade ≥4 ossification of the ungular cartilages than in feet with ossification grade ≤3. Thoroughbred (odds ratio [OR] 0.398) and Warmblood (OR 0.522) breeds had a lower risk of new bone formation on the proximal phalanx compared with other breeds. Increasing age was a risk factor for new bone formation on the proximal phalanx (OR 1.092) but was associated with reduced risk of new bone on the distal phalanx. New bone formation on the proximal and distal phalanges may contribute to pain and lameness.