The objective of this study was to evaluate the rotation and
translation of each joint in the hindfoot and compare the load response
in healthy feet with that in stage II posterior tibial tendon dysfunction
(PTTD) flatfoot by analysing the reconstructive three-dimensional
(3D) computed tomography (CT) image data during simulated weight-bearing. CT scans of 15 healthy feet and 15 feet with stage II PTTD flatfoot
were taken first in a non-weight-bearing condition, followed by
a simulated full-body weight-bearing condition. The images of the
hindfoot bones were reconstructed into 3D models. The ‘twice registration’
method in three planes was used to calculate the position of the
talus relative to the calcaneus in the talocalcaneal joint, the
navicular relative to the talus in talonavicular joint, and the cuboid
relative to the calcaneus in the calcaneocuboid joint.Objective
Methods
To introduce a new classification method and analyze related risk factor about lateral wall perforation associated with lower cervical pedicle screw and free-hand insertion technique. A Retrospective study was made to analyze 214 patients (1024 screws) with various cervical spine disorders, involved in pedicle screw instrumentation at C3-7 from July 2004 to July 2009. Researchers assessed the position of the screws in the pedicle by carefully probing intraoperatively and studying postoperative thin-slice computed tomography scan. Perforation of lateral wall was classified into two phases. Phase I refers to the burst of the pedicle by screw, which means that the length of screw threads penetrating the external cortex of pedicles on CT scan is 2 mm, whereas in Phase, the length is >2 mm. The Penetrated screws and related factors were analyzed though Backward Stepwise (Wald) Logistic regression.Introduction
Methods
Retrospective review. To report the technique and results of vertebral column decancellation (VCD) for the management of sharp angular spinal deformity.Study Design
Objective
How translation of different parts of spine responds to selective thoracic fusion has not been well investigated. Furthermore, how posterior pedicle-screw-only constructs affect spontaneous lumbar curve correction (SLCC) remains unknown. In a retrospective study, we aimed to investigate the balance change after selective thoracic fusion in Lenke 1C type adolescent idiopathic scoliosis (AIS) treated with posterior pedicle-screw-only constructs. All AIS cases, surgically treated between 2002 and 2008 in our institute, were reviewed. Inclusion criteria were: patients with Lenke 1C scoliosis treated with posterior pedicle-screw-only constructs; the lowest instrumented vertebra (LIV) ended at L1 level or above; and a minimum 2-year radiographic follow-up. Standing anteroposterior (AP) and lateral digital radiographs from different timepoints (preoperative, immediately postoperative, 3 months postoperative, and final follow-up) were reviewed. In each standing AP radiograph, centre sacral vertical line (CSVL) was drawn first, followed by measurement of the translation (deviation from the CSVL) of some key vertebrae, such as the LIV, LIV+1 (the first vertebra below LIV), LIV+2 (the second vertebra below LIV), LIV+3 (the third vertebra below LIV), lumbar apical vertebra, thoracic apical vertebra, and T1. Additionally, the Cobb angles of major thoracic and lumbar curve were measured at different timepoints, and the correction rate was calculated. Furthermore, clinical photos of patients' back appearance were taken preoperatively and postoperatively.Introduction
Methods
Progressive arthritis can occur in association with massive tears of the rotator cuff. Altered joint kinematics are commonly proposed as the principle causative factor but this does not explain the absence of arthropathy in some patients. We have investigated the role of the
Cuff Tear Arthropathy is characterised by massive rotator cuff tears, glenohumeral joint destruction and joint effusions containing basic calcium phosphate and calcium pyrophosphate dihydrate crystals. We have investigated the role of the ANKH gene in patients with cuff tear arthropathy and the effect of mutations on protein function. The transmembrane protein ANKH transports inorganic pyrophosphate (PPi) from the intracellular to extracellular space. Control of the extracellular levels of PPi is crucial in preventing calcium crystal formation. Genomic DNA was prepared from peripheral blood leucocytes from 22 patients with cuff tear arthropathy diagnosed clinically and radiologically. All 12 exons and exon-intron boundaries from the ANKH gene were PCR amplified and sequenced with BigDye version 3.1 terminator kit (ABI), and analysed using ABI PRISM ® 3100 Genetic Analyser. ANKH complementary DNA (cDNA) was ligated with mammalian expression vector pcDNA3 and site directed mutagenesis was used to make the ANKH mutation detected in the cases. Human articular chondrocytes were transfected with the cDNA variants and PPi concentrations measured. A G-to-A single nucleotide polymorphism in the 3′ untranslated region (3′UTR) of ANKH was identified. The G/A genotype was seen more frequently in the cases (45%) when compared to controls (20%) (p= 0.0008). We observed altered levels of extracellular PPi in human chondrocytes transfected with ANKH cDNA with the 3′ UTR variant when compared with control cells and normal ANKH cDNA. Cuff Tear Arthropathy appears to be heritable via a G-to-A transition in the 3′UTR of ANKH that alters extracellular PPi concentrations in chondrocyte cells. This supports a hypothesis of a primary crystal mediated arthropathy in patients with Cuff Tear Arthropathy.
