[Angular and torsional malalignments of the paediatric knee joint]. / Achsen- und Drehfehler des kindlichen Kniegelenks.

BACKGROUND: Abnormal angular and torsional alignment of the lower extremities during growth are a common reason for consultation of a paediatrician or orthopaedist. There is often uncertainty about the pathological value of these abnormalities and the need for treatment, even among specialists. In the course of physiological growth and development processes, the axial and torsional alignment of the legs sometimes change considerably and in characteristic patterns. DIAGNOSTICS: The ability to assess whether abnormal angular or torsional alignments of the lower limb in the course of growth should still be regarded as normal or already as pathological, depending on age and gender, is essential for the treating physician and requires precise knowledge of the physiological development processes and the tolerable limits in all three spatial dimensions. TREATMENT: After careful explanation to the frequently concerned parents, a restrictive approach with observation of the spontaneous course of correction on the basis of regular clinical check-ups makes sense in the majority of cases. Pathological deviations from the physiological conditions are rare overall, can be idiopathic or of secondary origin and should be further clarified diagnostically using imaging procedures. As conservative measures are ineffective, pronounced angular and/or torsional deformities of the legs requiring treatment can only be corrected by surgical intervention, even in children and adolescents. The surgical treatment modalities available are varied and differ in terms of their invasiveness and complication profile, depending on the localization, type and severity of the deformity, as well as the age and possible concomitant diseases of the affected child or adolescent.

Femoral anteversion linked to the inability to squat: Analysis of CT images in the patient and control groups.

Many patients who cannot squat well in a neutral toe position can only squat in an excessively out-toeing position. This excessive out-toeing squat is thought to be caused by rotational problems of the lower extremities. In this study, we aimed to identify the cause for the inability to squat by measuring and comparing femoral and tibial torsion between an excessive out-toeing squat patient group and a control group representing the general population. Between 2008 and 2022, a patient group comprising 50 lower extremities with excessive out-toeing squats was established. A control group representing the general population was selected from patients aged 0 to 29 years, who underwent lower-extremity CT angiography between 2012 and 2022, using the Clinical Data Warehouse with exclusion criteria applied. A total of 94 lower extremities were included in the control group. The femoral torsional angle (FTA) and tibial torsional angle (TTA) of both groups were measured and compared using Student t test. Additionally, 30 each of those with the highest and lowest 30 FTA values were selected from the patient and control groups, and the TTA was compared between the high- and low-FTA groups using Student t test. The mean FTA was 0.34° (SD, 11.11°) in the patient group and 10.14° (SD, 11.85°) in the control group, with a mean difference of 9.8° and P < .001. The mean TTA was 27.95° (SD, 7.82°) in the patient group and 32.67 ° (SD, 7.58°) in the control group, with a mean difference of 4.72° (P = .001). The mean TTA was 34.3° (SD, 7.72°) in the high-FTA group and 28.17° (SD, 8.35°) in the low-FTA group, with a mean difference of 6.13° (P = .005). Patients with excessive out-toeing squat showed lower FTA and TTA values than the general population. Furthermore, although a correlation between FTA and TTA was not established through Pearson correlation analysis, a tendency was observed where a decrease in FTA was associated with a decrease in TTA. Based on these results, decreased FTA was demonstrated to be one of the major causes of excessive out-toeing squats.

Coronal and axial alignment relationship in Caucasian patients with osteoarthritis of the knee.

Individualized pre-operative assessment of the patterns of the lower extremity anatomy and deformities in patients undergoing total knee arthroplasty seems essential for a successful surgery. In the present study, we investigated the relationship among the coronal alignment and the rotational profile of the lower extremities in the Caucasian population with end-stage knee osteoarthritis. We conducted a prospective study of 385 knees that underwent a pre-operative three-dimensional computed tomography-based model. The lower extremity alignment was determined (mechanical tibiofemoral or hip-knee-ankle angle, supplementary angle of the femoral lateral distal angle, and proximal medial tibial angle). For each case, the femoral distal rotation (condylar twist angle), the femoral proximal version, and the tibial torsion were determined. As the coronal alignment changed from varus to valgus, the femoral external rotation increased (r = 0.217; p < 0.0005). As the coronal alignment changed from varus to valgus, the external tibial torsion increased (r = 0.248; p < 0.0005). No correlation was found between the global coronal alignment and the femoral version. The present study demonstrates a linear relationship between the coronal alignment and the rotational geometry of the distal femur. This correlation also occurs with the tibial torsion. Perhaps outcomes of total knee arthroplasty surgery might be improved by addressing these deformities as well.

The impact of symptomatic femoral neck anteversion and tibial torsion on gait, function and participation in children and adolescents.

BACKGROUND: Torsional deformities of the lower limbs in children and adolescents are a common cause of in-toeing gait and cause gait deviations. The purpose of this study was to examine the relationship of children and adolescents with suspected Idiopathic Torsional Deformities (ITD) and pain, gait function, activity and participation. METHODS: A retrospective review of all children and adolescents who attended our Centre over a 5-year period for evaluation of the effect of ITD. All children completed three-dimensional gait analysis (3DGA), standardized physical examination, medical imaging and the Pediatric Outcomes Data Collection Instrument (PODCI). Statistical analysis was completed using two sample t-tests, Pearson's Correlation and linear regression. RESULTS: Fifty children and adolescents, 40 females and 10 males with a mean age of 13.5 years were included. Children reported a high prevalence of pain(86%), had increased internal hip rotation(p = 0.002) and decreased external hip rotation(p < 0.001) on physical examination when compared to published normative data. Medical imaging showed a mean(SD) femoral neck anteversion (FNA) of 38°(13°) and external tibial torsion of 39°(12°). Mean(SD) PODCI score was 32(16), indicating these children are functioning below their typically developing peers. The 3DGA kinematics show deviations from typical data including hip rotation, foot progression, pelvic tilt, hip flexion and knee extension. Observed mild kinetic deviations were within typical limits. The relationship between FNA and gait parameters, FNA and PODCI and gait and PODCI were weak. SIGNIFICANCE: These children and adolescents have altered gait and experience pain leading to impaired function and diminished participation. Therefore, ITD is not purely a cosmetic issue.

Intraperitoneal focal fat infarction: the great mimicker in the acute setting.

The term intraperitoneal focal fat infarction (IFFI) includes various self-limiting clinical conditions that are caused by focal fatty tissue necrosis. Most of the cases of IFFI concern torsion or infarction of the greater omentum or the epiploic appendages. However, although rarely, perigastric ligaments can also undergo torsion also leading to fat infarction. IFFI clinically may mimic other pathologies, such as acute appendicitis or diverticulitis, making their clinical diagnosis a challenge. Ultrasound (US) and computed tomography (CT) have a high sensitivity and specificity for the diagnosis of IFFI excluding other pathologies, and in most cases, the clinical evolution is spontaneously favorable, thus helping to reduce the need for unnecessary surgical intervention. We review cases with IFFI in order to identify specific involvement patterns. Cases of epiploic appendages reported to an acute, subacute, and more chronic phase in order to present the self-limiting nature of this entity and the resultant absorption. We also present cases with falciform ligament infarction, as well as primary ("whirl sign" on CT due to greater omentum torsion) and secondary omental infarctions. The aim of this pictorial review is not only to extensively explore the imaging findings of IFFI but to also describe the clinical presentation and pathophysiology of the prementioned conditions.

Femoral Derotation Osteotomy Improves Hip and Spine Function in Patients With Increased or Decreased Femoral Torsion.

PURPOSE: To evaluate the outcomes of proximal femoral derotation osteotomy (PFDO) on the hip and spine function of patients with abnormal femoral torsion. METHODS: This retrospective study included patients who underwent PFDO to treat increased or decreased femoral torsion between July 2014 and February 2019. The exclusion criteria were: previous fracture, fixation of slipped capital femoral epiphysis or osteotomy in the ipsilateral femur; PFDO associated to varus or valgus osteotomy; Tönnis grade 2 or 3 osteoarthritis; and PFDO performed to treat knee abnormalities. Hip function was assessed through the modified Harris Hip Score (mHHS). A subgroup of consecutive patients with low back pain before the PFDO and operated after 2017 had the spine function assessed through the Oswestry disability index (ODI). RESULTS: A total of 37 hips (34 patients) were studied: 15 hips with increased femoral torsion and 22 with decreased femoral torsion. Eight patients were male and 26 were female. The average age at PFDO was 33 years (range, 15-54 years). At a mean follow-up of 24 months (range, 12-65 months), the mean mHHS improved from 58.1 ± 14.3 before PFDO to 82 ± 15.6 at the most recent follow-up (P < .001). Improvement in the mHHS above the minimum clinically important difference (MCID) was observed in 33 hips (89%). In the subgroup of 14 consecutive patients with ODI available, the ODI improved from a mean of 45% ± 16% before the PFDO to 22% ± 17% at the most recent follow-up (P = .001). Nine (64.3%) of the 14 patients presented improvement in the ODI above the MCID. Revision procedure with a larger intramedullary nail was necessary in 2 hips to treat nonunion. CONCLUSION: Proximal femoral derotation osteotomy improves the hip and spine function in patients with increased or decreased femoral torsion and nonarthritic hips. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Estimating umbilical cord flow resistance from measurements of the whole cord.

Measuring umbilical blood pressure in utero is challenging and for this reason non-invasive methods are required. However, the total vessel blood pressure drop can be estimated using numerical and empirical results by studying the mechanics of fluids in coiled and straight tubes. Two key findings emerge from such an analysis. Firstly, the total pressure drop along a vessel at a given blood flow-rate depends on both the tightness of the coils and the total cord length. Relatively short and straight cords exhibit low pressure, while long, tightly coiled cords with large width exhibit high pressure. It follows that an estimate of the pressure requires three measurements: the full cord length, its average width and number of coils. Using this result we propose two prototype indices for clinical testing that estimate umbilical cord flow resistance. The umbilical pressure index (PX) and flow index (QX) quantify the deviation of a cord geometry from defined typical conditions by considering the steady pressure drop and flow-rate, respectively. These indices can be quickly calculated, and require only a single additional measurement to the conventional umbilical coiling index (UCI); namely the cord coiling width. Unlike the UCI, these indices are derived from blood-flow properties and provide a measure of the relative flow-resistance inherent to a cord geometry. Furthermore, the pressure index can be applied to irregularities, including loose true knots, which we show must be accounted for.

Case Report: Ocular Tilt Reaction with Internuclear Ophthalmoplegia and Multiple Cranial Nerve Palsies.

SIGNIFICANCE: Ocular tilt reaction (OTR) is an abnormal eye-head postural reaction that consists of skew deviation, head tilt, and bilateral ocular torsion. Understanding of the pathway of the vestibulo-ocular reflex (VOR) is essential because this will help to localize the pathology. PURPOSE: The aim of this study was to report a case of OTR with contralateral internuclear ophthalmoplegia (INO) and fifth and seventh cranial nerve palsies. CASE REPORT: A 51-year-old gentleman with underlying diabetes mellitus presented with sudden onset of diplopia for 3 days. On examination, his visual acuity was 20/30 bilaterally without a relative afferent pupillary defect. He had a right OTR consisting of a right head tilt, a skew deviation with a left eye hypertropia, and bilateral ocular torsion (right excyclotorsion and left incyclotorsion) with nystagmus. He also had a left adduction deficit and right abduction nystagmus consistent with a left INO. Ocular examination revealed evidence of proliferative diabetic retinopathy bilaterally. Two days after the initial presentation, the patient developed left seventh and fifth cranial nerve palsies. MRI showed left pontine infarction and multiple chronic lacunar infarctions. There was an incidental finding of a vascular loop compression on cisternal portions of the left trigeminal, facial, and vestibulocochlear nerves. Antiplatelet treatment was started on top of a better diabetic control. The diplopia was gradually resolved with improved clinical signs. In this case, the left pontine infarction had likely affected the terminal decussated part of the vestibulocochlear nerve from the right VOR pathway, medial longitudinal fasciculus, and cranial nerve nuclei in the left pons. CONCLUSIONS: The OTR can be ipsilateral to the lesion if the lesion is before the decussation of the VOR pathway in the pons, or it can be contralateral to the lesion if the lesion is after the decussation. In case of an OTR that is associated with contralateral INO and other contralateral cranial nerves palsy, a pathology in the pons that is contralateral to the OTR should be considered. Neuroimaging study can hence be targeted to identify the possible cause.

Modified Anterior Superior Oblique Tuck: A Case Series.

PURPOSE: Selection of the ideal procedure to correct symptomatic excyclotropia depends on several factors including the degree of torsion and associated vertical, horizontal and pattern deviation. Selective tuck of the anterior temporal torsional fibers of the superior oblique (SO) tendon is an alternative procedure to the classical Harada-Ito. The purpose of this study is to report its stability and results. METHODS: Retrospective review of all consecutive patients with symptomatic excyclotorsion of at least 5º (degrees) treated by selectively splitting and tucking the anterior temporal fibers of the SO tendon. Torsion in primary position was measured using the double Maddox Rods. Patients with additional symptomatic vertical or horizontal diplopia underwent simultaneous surgery on other extraocular muscles. RESULTS: Five patients were studied. Mean age was 60 ± 8 years (47-67). Mean postoperative follow-up was 10 ± 8 months (3-21). The mean preoperative torsion of 11º±4º (7º-15º) significantly decreased to 3º±2º (p = .03) at the first postoperative visit (16 ± 9 days) and 3 ± 2º during the last visit (P = .03). The procedure corrected 1.4º±0.9º per mm of tuck. Postoperatively no patient complained of torsion. No undesirable vertical or horizontal deviations were noted. CONCLUSION: This technique is a simple alternative to manage symptomatic excyclotorsion, with significant and stable relief of moderate amounts of torsion and without inducing unexpected vertical or horizontal deviation.

Detection of and Compensation for Static Cyclotorsion With an Image-Guided System in SMILE.

PURPOSE: To evaluate the effect of cyclotorsion compensation with an image-guided system (Callisto eye; Carl Zeiss Meditec AG, Jena, Germany) on the visual and refractive outcomes of small incision lenticule extraction (SMILE) surgery for astigmatism. METHODS: The medical records of 124 right eyes of 124 patients with astigmatism of 0.75 diopters (D) or greater who underwent SMILE for myopic astigmatism were reviewed. Patients were treated with cyclotorsion compensated SMILE or standard SMILE. After the sitting position reference axis was registered with IOLMaster 700 (Carl Zeiss Meditec AG), these data were transferred to the Callisto eye system, which was connected to the operating VisuMax microscope (Carl Zeiss Meditec AG). Cyclotorsion was measured by activating the Z-align function and compensated for by repositioning the patient's body or tilting the head until the reference axis from the IOLMaster 700 (0-180) was parallel to a manually drawn reference axis on the screen (0-180) before docking. The visual and refractive results were studied preoperatively and postoperatively. Astigmatic changes were interpreted using the Alpins method. RESULTS: Six months after surgery, the results showed that the astigmatic eyes in the cyclotorsion compensated group had improved axial alignment, more precise astigmatic correction, and better postoperative uncorrected distance visual acuity (UDVA) compared with the standard group. The mean logMAR UDVA was 0.02 ± 0.10 (range: -0.15 to 0.30) and 0.06 ± 0.11 (range: -0.15 to 0.30) (P = .13) and the mean astigmatic error was -0.19 ± 0.17 D (range: -0.50 to 0.00 D) and -0.45 ± 0.38 D (range: -1.50 to 0.00 D) (P < .001) in the cyclotorsion compensated group and the standard group, respectively. In regard to vector analysis, the mean index of success was 0.00 ± 0.00 (range: 0.00 to 0.00) and 0.40 ± 0.48 (range: 0.00 to 2.72) (P < .001), and the mean absolute angle of error in degrees was 1.18 ± 2.23 (range: 0.00 to 13.00) and 3.76 ± 3.80 (range: 0.00 to 14.00) (P < .001) in the cyclotorsion compensated group and the standard group, respectively. CONCLUSIONS: The combination of the Callisto eye system with a VisuMax laser might be an efficacious and reliable approach to enhance astigmatism treatment with SMILE surgery. [J Refract Surg. 2020;36(3):142-149.].

Increased femoral anteversion related to infratrochanteric femoral torsion is associated with ACL rupture.

PURPOSE: To determine the association between femoral torsion and anterior cruciate ligament (ACL) rupture and determine the level of torsion using magnetic resonance imaging (MRI). METHODS: The medical records of patients who were diagnosed with ACL injury were reviewed retrospectively. This descriptive epidemiological study included 2344 patients. MRI scans were examined and patients with femur and knee MRI scans obtained at the same time were identified (ACL-deficient group). Twenty-eight of them had femur and knee MRI scans because of an incidental benign lesion in the distal femur. Patients who were diagnosed with enchondroma were followed up by MRI evaluation of the femur and were randomly selected as controls. Supratrochanteric torsion (STT), infratrochanteric torsion (ITT), and femoral anteversion (FA) were measured by orthopedic surgeons with at least 5 years of experience. RESULTS: Age, sex, and side properties were similar in both groups. The mean FA values were 19.4 ± 3.0 degrees and 11.9 ± 2.0 degrees in the ACL-deficient and control groups, respectively (p < 0.001). STT was similar in the ACL-deficient and control groups [mean: 38.2 ± 4.3 and 37.7 ± 3.3, respectively, (n.s.)]. ITT was increased in the ACL-deficient group compared with the control group (mean - 18.8 ± 4.3 and - 25.8 ± 3.8, respectively; p < 0.001). CONCLUSIONS: According to our results, increased FA was associated with ACL rupture. Further, the torsional abnormality was developed from the ITT. We concluded that each ACL-deficient patient should be assessed by a clinician for torsional abnormality using physical examination. LEVEL OF EVIDENCE: III.

Optimal Blood Pressure Control Improves Left Ventricular Torsional Deformation and Vascular Function in Newly Diagnosed Hypertensives: a 3-Year Follow-up Study.

We investigated the effects of optimizing blood pressure control on cardiac deformation and vascular function. For this purpose, in 200 untreated patients with essential hypertension, we assessed at baseline as well as after 3 years of optimal blood pressure control: arterial stiffness and coronary microcirculatory function as well as longitudinal and torsional deformation parameters. Compared to baseline, after 3 years of optimal blood pressure control, there was an improvement of longitudinal strain, twisting as well as untwisting parameters of the left ventricle. In parallel, there was an improvement in coronary microcirculatory function, arterial stiffness, left ventricular mass, and ventricular-arterial interaction. The reduction of arterial stiffness was independently associated with the respective improvement of cardiac deformation markers and coronary flow reserve after adjusting for blood pressure improvement. Blood pressure optimization improves LV longitudinal and torsional mechanics in hypertensives in parallel with arterial stiffness, resulting in improved ventricular-arterial interaction and coronary flow reserve. Trial registration: ClinicalTrials.gov Identifier: NCT02346695.

Compensatory gait deviations in patients with increased outward tibial torsion pre and post tibial derotation osteotomy.

BACKGROUND: Tibial torsion describes the rotation between the proximal and distal joint axis along the shaft, which can be, as rotational deformity, pathologically increased or decreased. Some patients might increase hip internal rotation during walking to compensate increased outward tibial torsion. RESEARCH QUESTION: The aim of this study was to assess the effect of tibial derotation osteotomy on gait deviations in patients with increased outward tibial torsion. METHODS: Thirteen patients (13.5 ± 1.4 yrs, 22 limbs) with increased tibial torsion (CT confirmed 49.2 ± 4.8°) were analyzed pre and post tibial derotation osteotomy and compared with 17 typically developing children (TDC, 13.5 ± 2.3 yrs, 32 limbs). Kinematic and kinetic data were recorded. Subgroup analyses were performed whether patients showed compensatory hip internal rotation (Comp) or not (NoComp). Principal component (PC) analysis was used to achieve data transformation. A linear mixed model was used to estimate the main effect of PC-scores of retained PCs explaining 90% of the cumulative variance. RESULTS: Compensatory hip internal rotation (Comp, present in 45.5% of limbs analyzed) led to a lower external foot progression angle compared to patients without compensatory hip internal rotation (NoComp). In both patient groups foot progression angle was normalized after tibial derotation osteotomy. Post-operative NoComp had normalized frontal plane joint loadings, while Comp showed an increased hip and knee adduction moment. SIGNIFICANCE: Future studies should investigate if more time is needed for Comp to normalize gait patterns post-operative or if a pre and post-operative gait training might help. Otherwise the increased knee adduction moment might be clinically relevant due to previous studies reporting a possible association with knee osteoarthritis.

In-toeing gait in children with clubfoot and the effect of tibial rotation osteotomy.

In-toeing gait is common after treatment for clubfoot deformity and is often secondary to residual internal tibial torsion. The purpose of the current study was to characterize the gait pattern in children with an intoeing gait pattern associated with talipes equinovarus (TEV) deformity, identify secondary changes at the hip that occur with intoeing, and determine if these secondary effects resolve after correction of tibial torsion. Patients with a diagnosis of TEV deformity, in-toeing gait secondary to residual internal tibial torsion corrected with tibial rotation osteotomy (TRO) and complete preoperative and postoperative motion analysis studies obtained approximately 1 year apart, were included in the study. Nineteen children (19 left extremities) with a TRO at a mean age of 8.2 years met inclusion criteria. Clinical examination showed improvement in tibial torsion assessment by measure of the thigh foot axis and transmalleolar axis. Kinematically, an abnormal internal FPA was present in all cases preoperatively, was corrected to normal in 12 (63%), remained internal in 5 (26%), and was abnormally external in 2 (11%). External hip rotation was identified in 13 (68%) cases preoperatively. Hip rotation was normalized postoperatively in 7 (54%), and was unchanged in the remaining 6 (46%). TRO provides effective correction of excessive internal tibial torsion, resolution of kinematic internal knee rotation, and normalization of the internal foot progression angle in the majority of patients with TEV deformity. External hip rotation resolved in approximately 50% of cases. Overcorrection of the internal FPA is possible when secondary changes at the hip do not resolve.

Premenarchal patients present differently: A twist on the typical patient presenting with ovarian torsion.

BACKGROUND/PURPOSE: The aim of this study was to characterize differences between pre- and postmenarchal females with ovarian torsion. METHODS: A single-center review was conducted of all nonneonatal pediatric patients with ovarian torsion from 2011 to 2018. Clinical data were compared between pre- and postmenarchal patients. RESULTS: One hundred and twenty-seven patients were identified, and 25% were premenarchal. Premenarchal patients were more likely to have a delay in diagnosis (38% vs 20%, p = 0.042), develop ovarian necrosis (34% vs 17%, p = 0.036), and present without an associated adnexal mass (44% vs 0%, p < 0.001). All patients without a mass (n = 14) were premenarchal and presented with ovarian asymmetry. Patients without an associated mass underwent oophoropexy in the majority of cases. There were no differences in postoperative complication or recurrence rates between groups. CONCLUSION: Premenarchal females with ovarian torsion can present differently than females postmenarche and often have a delay in diagnosis. Premenarchal females are more likely to undergo torsion without an associated adnexal mass and are at higher risk for ovarian necrosis. Oophoropexy is an appropriate treatment in the absence of an adnexal mass. A high-index of suspicion for ovarian torsion should be maintained for premenarchal females presenting with abdominal pain and an otherwise negative workup. TYPE OF STUDY: Retrospective comparative study. LEVEL OF EVIDENCE: Level III.

Role of Rotation in Total Ankle Replacement.

BACKGROUND: The importance of total ankle replacement (TAR) implant orientation in the axial plane is poorly understood with major variation in surgical technique of implants on the market. Our aim was to better understand the axial rotational profile of patients undergoing TAR. METHODS: In 157 standardized computed tomography (CT) scans of patients with end-stage ankle arthritis planning to undergo primary TAR surgery, we measured the relationship between the knee posterior condylar axis, the tibial tuberosity, the transmalleolar axis (TMA), and the tibiotalar angle. The foot position was measured in relation to the TMA with the foot plantigrade. The variation between the medial gutter line and the line bisecting both gutters was assessed. RESULTS: The mean external tibial torsion was 34.5 ± 10.3 degrees (11.8-62 degrees). When plantigrade, the mean foot position relative to the TMA was 21 ± 10.6 degrees (0.7-38.4 degrees) internally rotated. As external tibial torsion increased, the foot position became more internally rotated relative to the TMA (Pearson correlation, 0.6; P < .0001). As the tibiotalar angle became more valgus, the foot became more externally rotated relative to the TMA (Pearson correlation, -0.4; P < .01). The mean difference between the medial gutter line and a line bisecting both gutters was 4.9 ± 2.8 degrees (1.7-9.4 degrees). More than 51% of patients had a difference greater than 5 degrees. The mean angle between the medial gutter line and a line perpendicular to the TMA was 7.5 ± 2.6 degrees (2.8-13.7 degrees). CONCLUSION: There was a large variation in rotational profile of patients undergoing TAR, particularly between the medial gutter line and the TMA. Surgeon designers and implant manufacturers should develop consistent methods to guide surgeons toward judging the appropriate axial rotation of their implant on an individual basis. We recommend careful clinical assessment and preoperative CT scans to enable the correct rotation to be determined. LEVEL OF EVIDENCE: Level IIc, outcomes research.

In Vivo Measurement of Cervical Elasticity on Pregnant Women by Torsional Wave Technique: A Preliminary Study.

A torsional wave (TW) sensor prototype was employed to quantify stiffness of the cervix in pregnant women. A cross-sectional study in a total of 18 women between 16 weeks and 35 weeks + 5 days of gestation was performed. The potential of TW technique to assess cervical ripening was evaluated by the measurement of stiffness related to gestational age and cervical length. Statistically significant correlations were found between cervical stiffness and gestational age ( R 2 = 0.370 , p = 0.0074 , using 1 kHz waves and R 2 = 0.445 , p = 0.0250 , using 1.5 kHz waves). A uniform decrease in stiffness of the cervical tissue was confirmed to happen during the complete gestation. There was no significant correlation between stiffness and cervical length. A stronger association between gestational age and cervical stiffness was found compared to gestational age and cervical length correlation. As a conclusion, TW technique is a feasible approach to objectively quantify the decrease of cervical stiffness related to gestational age. Further research is required to evaluate the application of TW technique in obstetric evaluations, such as prediction of preterm delivery and labor induction failure.

Comparison of ocular torsion between congenital and acquired unilateral superior oblique palsy.

BACKGROUND/OBJECTIVES: To compare ocular torsion between congenital and acquired unilateral superior oblique palsy (USOP). SUBJECTS/METHODS: Retrospective review was performed on medical records of 163 USOP patients. Qualitative fundus torsional states in both eyes were determined based on locations of optic disc and fovea. Disc-fovea angles (DFA) were collected in both eyes for quantitative analysis. DFAs and the proportions of qualitative fundus torsional states in paretic and non-paretic eyes were compared between USOP patients and normal controls, and between congenital and acquired USOP patients. RESULTS: This study included 90 patients with congenital USOP, 73 patients with acquired USOP, and 66 normal controls. Most control subjects showed no torsion in both eyes (93.9%), whereas 61.1% of congenital and 46.5% of acquired USOP patients showed extorsion in either eye. More patients with congenital USOP showed fundus extorsion in the non-paretic eye (24.4% versus 12.3%) or both eyes (20.0% versus 6.8%), compared with patients with acquired USOP (P = 0.007). DFAs of paretic and non-paretic eyes were larger in USOP patients than in normal controls (P < 0.001, for both congenital USOP versus control and acquired USOP versus control). DFAs of non-paretic eyes were larger in congenital USOP patients than in acquired USOP patients (10.3° versus 8.5°, P = 0.018). CONCLUSIONS: Congenital USOP showed greater fundus extorsion in the non-paretic eye, compared with acquired USOP. Fundus photographs of both eyes are necessary to understand the ocular torsion in USOP patients and the variations in fundus torsion with varying USOP aetiology.