Three-dimensional spinal motion measurements. Part 2: A noninvasive assessment of lumbar brace immobilization of the spine

The purpose of this study was to evaluate the limitation of motion as well as comfort provided by four different types of lumbar braces. The four braces were the Raney jacket, the Camp lace-up corset, a molded-polypropylene thoracolumbar-sacral orthosis (TLSO), and a common elastic corset. The data revealed that all braces significantly restrict free lumbar and thoracic motion in the sagittal and frontal planes. All braces restricted lumbar motion more in the frontal than in the sagittal plane. The rigid TLSO and Raney jackets were most restrictive when compared with the Camp corset and the elastic corset. Axial rotation in the lumbar spine is normally minimal and further limitation by a brace would be negligible. All braces restricted thoracic motion despite the fact that lumbar braces were used. The elastic corset was rated the most comfortable and the Raney jacket the least comfortable. This verifies that there is an inverse relationship between a brace's ability to restrict motion and comfort.     

Three dimensional analysis of brace biomechanical efficacy for patients with AIS

Purpose

Corrective three dimensional (3D) effect of different braces is debatable. We evaluated differences in in-brace radiographic correction comparing a custom thoracic-lumbo-sacral-orthosis (TLSO) (T) brace to a Chêneau type TLSO (C) brace using 3D EOS reconstruction technology. Our primary research question was the 3D effect of brace on the spine and in particularly the apical vertebra rotation (AVR).

Methods

This was a retrospective comparative analysis of patients with adolescent idiopathic scoliosis who had orthogonal AP and lateral X-rays with and without brace. A 3D image of the spine was reconstructed. Coronal, sagittal and axial spine parameters were measured before bracing and then on the first post-brace X-ray. Brace efficacy in controlling coronal, sagittal and axial parameters was evaluated.

Results

Eighteen patients treated with the C brace and ten patients treated with the T brace were included. No difference was found regarding patients’ age, gender, magnitude of Cobb angle, sagittal parameters or AVR at inclusion. Following bracing, AVR was significantly reduced by the C brace compared to the T brace [average correction of 8.2° vs. 4.9° (P = 0.02)]. Coronal and sagittal correction did not differ significantly between the two groups.

Conclusions

By utilizing a novel 3D reconstruction technology, we were able to demonstrate that braces differ in their immediate effects on the spine. Although clinical relevance should be evaluated in a future trial we feel that the ability to measure treatment effects in 3D, and especially the transverse plane, is an important tool when evaluating different treatments.     

Does the use of postoperative brace help preventing mechanical complications following adult deformity surgery?

Purpose

There is scarce information regarding the effectiveness of postoperative braces in decreasing mechanical complications and reinterventions following adult deformity surgery.

Methods

Retrospective matched cohort study from a prospective adult deformity multicenter database. We selected operated patients, fused to the pelvis, > 6 instrumented levels, and minimum 2 year follow-up. Three hundred and eighty patients were separated into two groups (Brace—3 months TLSO—vs No Brace) and then matched controlling for age, gender and frailty. We studied demographic, intraoperative, and postoperative spinopelvic parameters. Both groups were compared regarding complications and reinterventions in the first 2 postoperative years, using univariate and multivariate logistic regression analysis.

Results

We finally analyzed 359 matched patients, mean age of 65.3 ± 8.9 years, frailty-index (0.43 ± 0.15), and mostly females (84%). 224 patients wore a postoperative brace (B) and 135 didn’t (NoB). They showed no difference in intraoperative variables and postoperative spinopelvic alignment. They differed (P < 0.05) in: Pelvic incidence (B:58° ± 13 vs NoB:54.5° ± 13); BMI (B:25.8 ± 4 vs NoB:27.4 ± 5); upper instrumented vertebra (B:81.7% T8-L1 vs NoB:72.6% T8-L1), and the use of multiple rods (B:47.3% vs NoB:18.5%). Univariate analysis showed a higher rate of mechanical complications and reinterventions when not using a brace. As well as higher NRS—back and leg pain at 6 weeks. However, multivariate analysis selected the use of multiple rods as the only independent factor protecting against mechanical complications (OR: 0.38; CI 95% 0.22–0.64) and reinterventions (OR: 0.41; CI 95% 0.216–0.783).

Conclusion

After controlling for potential confounders, our study could not identify the protective effect of postoperative braces preventing mechanical complications and reinterventions in the first two postoperative years.

     

Scoliosis in-brace curve correction and patient preference of CAD/CAM versus plaster molded TLSOs

Purpose CAD/CAM technology is a newer technique for creating spinal orthoses than standard plaster molded methods. To our knowledge there has been only one previous study of CAD/CAM braces. The purpose of our study was to compare patient preference and in-brace correction of Cobb angle between plaster molded thoracolumbosacral orthoses (TLSO) and CAD/CAM designed TLSOs in a series of patients with scoliosis. Methods Ten patients with an average initial Cobb angle of 30.8° (range 18°–46°) had both a plaster molded TLSO and a CAD/CAM TLSO fabricated for them. In each case, the decision to brace was made by the treating surgeon based on curve magnitude and skeletal maturity. After 3 weeks of 23 h a day wear, in-brace correction of the Cobb angle was measured for each brace based on standard PA spine radiographs. After 3 months of use, patients were asked which brace they preferred. Results For the CAD/CAM brace, the mean curve correction after 3 months was 51% compared to 44% in the plaster molded TLSO cohort. (p = 0.46). Seven out of nine patients preferred the CAD/CAM TLSO over the plaster molded TLSO. There were no brace complications in either group. Conclusion In our matched cohort study, CAD/CAM TLSOs had at least equivalent if not superior correction of the Cobb angle compared to standard plaster molded TLSOs; 78% of our patients preferred the CAD/CAM brace over the standard TLSO.     

Orthosis versus no orthosis for the treatment of thoracolumbar burst fractures without neurologic injury: a multicenter prospective randomized equivalence trial

Background contextThoracolumbar burst fractures have good outcomes when treated with early ambulation and orthosis (TLSO). If equally good outcomes could be achieved with early ambulation and no brace, resource utilization would be decreased, especially in developing countries where prolonged bed rest is the default option because bracing is not available or affordable.PurposeTo determine whether TLSO is equivalent to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures with respect to their functional outcome at 3 months.Study designA multicentre, randomized, nonblinded equivalence trial involving three Canadian tertiary spine centers. Enrollment began in 2002 and 2-year follow-up was completed in 2011.Patient sampleInclusion criteria included AO-A3 burst fractures between T11 and L3, skeletally mature and older than 60 years, 72 hours from their injury, kyphotic deformity lower than 35°, no neurologic deficit. One hundred ten patients were assessed for eligibility for the study; 14 patients were not recruited because they resided outside the country (3), refused participation (8), or were not consented before independent ambulation (3).Outcome measuresRoland Morris Disability Questionnaire score (RMDQ) assessed at 3 months postinjury. The equivalence margin was set at δ=5 points.MethodsThe NO group was encouraged to ambulate immediately with bending restrictions for 8 weeks. The TLSO group ambulated when the brace was available and weaned from the brace after 8 to 10 weeks. The following competitive grants supported this work: VHHSC Interdisciplinary Research Grant, Zimmer/University of British Columbia Research Fund, and Hip Hip Hooray Research Grant. Aspen Medical provided the TLSOs used in this study. The authors have no financial or personal relationships that could inappropriately influence this work.ResultsForty-seven patients were enrolled into the TLSO group and 49 patients into the NO group. Forty-six participants per group were available for the primary outcome. The RMDQ score at 3 months postinjury was 6.8±5.4 (standard deviation [SD]) for the TLSO group and 7.7±6.0 (SD) in the NO group. The 95% confidence interval (?1.5 to 3.2) was within the predetermined margin of equivalence. Six patients required surgical stabilization, five of them before initial discharge.ConclusionsTreating these fractures using early ambulation without a brace avoids the cost and patient deconditioning associated with a brace and complications and costs associated with long-term bed rest if a TLSO or body cast is not available.     

Effectiveness of the Charleston bending brace in the treatment of single-curve idiopathic scoliosis.

The purpose of this study was to determine the effectiveness of the Charleston bending brace when compared with the thoracolumbosacral orthosis (TLSO or Boston) brace in the treatment of single-curve adolescent-type idiopathic scoliosis. The Charleston and TLSO braces were applied for approximately 8 nighttime hours and 18 to 22 hours per day, respectively. Treatment success was defined as improvement of curve deterioration with <5 degrees progression from the start of brace therapy until the conclusion of treatment, as well as the absence for the need to perform corrective surgery. The success rates were determined by Risser stage, initial angle, type of curvature, and sex of the patient. In addition, the success rate of the Charleston brace was assessed by analyzing the degree of initial correction. One hundred twenty-two patients (94 girls, 28 boys) were studied. Eighty-five patients were treated with the Charleston brace and 37 with the TLSO brace. Mean Cobb angle of curvature before bracing was 30.4 degrees. The curvature was lumbar in 60 patients, thoracic in 56, and thoracolumbar in 6. The average follow-up time was 23 months, with a minimum follow-up of 1 year. Surgery was performed in 11.8% and 13.5% of patients in the Charleston and TLSO groups, respectively. In this patient population, no significant difference in success rate was found between the groups.     

Is posterior percutaneous screw-rod instrumentation a safe and effective alternative approach to TLSO rigid bracing for single-level pyogenic spondylodiscitis? Results of a retrospective cohort analysis

Background contextCurrently, treatment for patients diagnosed with noncomplicated (ie, known infectious agent, no neurologic compromise, and preserved spinal stability) pyogenic spondylodiscitis (PS) is based on intravenous antibiotics and rigid brace immobilization. Since January 2010, we started offering our patients percutaneous posterior screw-rod instrumentation as an alternative approach to rigid bracing. Supposed benefits of posterior percutaneous instrumentation over rigid bracing are earlier free mobilization, increased comfort, and faster recovery.PurposeTo evaluate safety and effectiveness of posterior percutaneous spinal instrumentation for single-level PS and compare clinical and quality-of-life outcomes with standard thoracolumbosacral orthosis (TLSO) rigid bracing.Study design/SettingRetrospective observational cohort study.Patient sampleTwenty-seven patients consecutively diagnosed with single-level noncomplicated lower thoracic or lumbar PS from January 2010 to December 2011.Outcome measuresHealing rate, healing time, and changes in segmental kyphosis Cobb angle were compared in the two treatment groups. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and complete blood count at regular time points until complete healing were also obtained. Self-report measures included Visual Analog Scale (VAS), Short-Form 12 (SF-12), and EuroQol five-dimension (EQ-5D) questionnaires.MethodsAt enrollment, patients were offered to choose between 24/7 TLSO rigid bracing for 3 to 4 months and bridging posterior percutaneous screw-rod instrumentation followed by soft bracing for 4 weeks after surgery. All patients underwent antibiotic therapy accordingly to isolated infectious agents. Patients were seen in the clinic at 1, 3, 6, and 9 months, and ESR, CRP, complete blood count, VAS, SF-12, and EQ-5D questionnaires were obtained. Segmental kyphosis was measured at diagnosis and at 9 months follow-up. Two-way repeated-measures analysis of variance was used to assess group and time differences across time points.ResultsFifteen patients chose conservative treatment, whereas 12 patients chose surgical treatment. Complete infection healing was achieved in all patients with no significant differences in healing time (p<.366). C-reactive protein and ESR levels decreased in both groups accordingly with positive response to therapy with no significant differences. Surgically treated patients had significantly lower VAS scores at 1 month (2.76±0.80 vs. 5.20±1.21, p<.001) and 3 months (2.31±0.54 vs. 2.85±0.54, p<.016) post-diagnosis over TLSO patients. Moreover, surgery patients also showed steeper and statistically significant improvements in SF-12 scores over TLSO patients at 1, 3, and 6 months post-diagnosis (p<.012); no significant differences were detected at the other time points. EuroQol five-dimension index was significantly higher in surgery patients at 1 month (0.764±0.043 vs. 0.458±0.197, p<.001) and 3 months (0.890±0.116 vs. 0.688±0.142, p<.001); no significant changes were observed in segmental pre- and posttreatment kyphosis between the two groups. No instrumentation-related complications were observed in any patient.ConclusionsPosterior percutaneous spinal instrumentation is a safe, feasible, and effective procedure in relieving pain, preventing deformity, and neurologic compromise in patients affected by noncomplicated lower thoracic (T9–T12) or lumbar PS. Posterior instrumentation did not offer any advantage in healing time over TLSO rigid bracing because infection clearance is strongly dependent on proper antibiotic therapy. Nevertheless, surgical stabilization was associated with faster recovery, lower pain scores, and improved quality of life compared with TLSO conservative treatment at 1, 3, and 6 months after treatment.     

Lumbar spine orthosis wearing. II. Effect on trunk muscle myoelectric activity

The effects of wearing commonly prescribed low-back braces and corsets on myoelectric signal levels in the erector spinae and oblique abdominal muscles were investigated. A lumbosacral corset, a chairback brace, and a molded thoracolumbosacral orthosis (TLSO) were studied. Nineteen tasks involving sitting and standing were performed by five healthy adult men. Myoelectric signal levels measured when wearing each orthosis were compared with those measured when performing the same task while wearing no orthosis. The changes in mean myoelectric signal levels ranged from a 9% reduction to a 44% increase when the lumbosacral corset was worn, from a 27% reduction to a 25% increase when the chairback brace was worn, and from a 38% reduction to a 19% increase when the TLSO was worn.     

Effects of thoracolumbosacral orthosis on spinal deformities, trunk asymmetry, and frontal lower rib cage in adolescent idiopathic scoliosis

STUDY DESIGN: Prospective study. OBJECTIVES: To document immediate and late changes in shape and balance of the thoracic and lumbar spine and lower rib cage on the frontal plane induced by treatment with a thoracolumbosacral orthosis (TLSO). SUMMARY OF BACKGROUND DATA: The effect of TLSO on lateral plane of spinal deformity, frontal lower rib cage, trunk balance, and natural history are poorly understood. METHODS: Twenty-four female adolescents with major thoracic and/or lumbar scoliosis, averaging 30 degrees and 26 degrees, respectively, were treated with a full-time TLSO program. Scoliosis, kyphosis, convex, and concave rib-vertebral angles T7 to T12, frontal trunk balance, frontal vertebral inclination, rotation and translation from T7 to L4-vertebrae were measured before bracing, 1 month after bracing, and biannually thereafter in brace and without brace for a 4-year period and reevaluated at the age of 20 years, at an average of 3.5 years after termination of bracing to measure any permanent changes. RESULTS: Thoracolumbosacral orthosis treatment corrected both thoracic and lumbar scoliosis and reduced lateral trunk shift at the expense of significant, although temporary reduced physiological thoracic kyphosis, increased lateral displacement of T7 to T10, increased frontal inclination of L2 to L4, and elevation of the apical concave rib in favor of reduction of lateral displacement of T11 to L4; decreased frontal inclination of T7, T9, and T11; and derotated L1 and L2 and thoracic apical vertebra without affecting drooping of the 7th to 12th ribs. In this series, there was marked inconsistency in the obtained changes in several of the roentgenographic parameters in the different evaluations, which is probably because of the empiric application of the TLSO during different periods of treatment. 3.5 years after termination of TLSO-wearing, all roentgenographic parameters remained to the prebrace values. CONCLUSIONS: Thoracolumbosacral orthosis program maintained the measured roentgenographic parameters at the prebrace levels in progressive adolescent idiopathic scoliosis, but it had no effect on the droop of the seven lower ribs. The TLSO treatment stopped progression of scoliosis and reduced the number of patients requiring surgery. Thus, it changed the natural history of scoliosis.     

Comparison of planned and achieved implant position in total knee arthroplasty with patient-specific positioning guides

Background and purpose — Intraoperatively, patient-specific positioning guides (PSPGs) represent the preoperatively planned alignment. We investigated the degree of correlation between preoperative planning and the alignment achieved postoperatively with the PSPG technique.

Patients and methods — TKAs performed with the PSPG technique between 2009 and 2011 were included. 39 patients (42 TKAs) volunteered for a postoperative CT scan. 2 independent observers performed the postoperative CT measurements. Preoperative component angles (target angles) in the coronal and axial planes were defined as 0 degrees, and in the sagittal plane on average 2.8 degrees for the femoral component and 3 degrees for the tibial component. A postoperative full-length standing anteroposterior radiograph was carried out in 41 TKAs.

Results — The femoral component was on average 1.2 (SD 1.5) degrees in varus, 4.4 (SD 4.0) degrees in flexion, and 0.5 (SD 1.4) degrees in external rotation. The tibial component was on average 0.4 (SD 2.5) degrees in varus and 3.7 (SD 2.3) degrees in flexion. A statistically significant difference between the target (preoperative software plan) and postoperative CT measurement was found for the femoral component angle in the frontal plane (p < 0.001; CI: 0.8–1.7), the sagittal plane (p = 0.01; CI –5.6 to –3.1), and the axial plane (p = 0.03; CI: 0.04–0.88). HKA angles were greater than 3 degrees from the neutral axis in 10 of the 41 cases.

Interpretation — We found our postoperative component alignment angles to be close to the software plan, especially for the tibial component. However, we found outliers in all planes and we cannot therefore conclude that the PSPG technique is a method that reproduces preoperatively planned alignment in a consistent manner.     

Tridimensional trunk surface acquisition for brace manufacturing in idiopathic scoliosis

Introduction

Brace manufacturing for idiopathic scoliosis requires trunk surface acquisition. Two methods are currently available to design the trunk shape: craft made technique based on a plaster mold and computer-aided design with 3-D reconstruction of the trunk by optical scanning. The objective of the present review was to compare these two methods.

Methodology

We describe the different steps to design and manufacture braces used for spinal deformities.

Results

Our prospective evaluation showed good results in terms of the correction achieved and regarding patients’ in-brace comfort.

Discussion

Optical scanning for computer-aided design and manufacturing (CAD-CAM) of trunk orthoses have proven their effectiveness. These technologies may help in monitoring conservative treatment and may enhance the brace interaction with the spinal deformity when orthopedic treatment is indicated.

     

Comparison of the biomechanical 3D efficiency of different brace designs for the treatment of scoliosis using a finite element model

The biomechanical influence of thoraco-lumbo-sacral bracing, a commonly employed treatment in scoliosis, is still not fully understood. The aim of this study was to compare the immediate corrections generated by different virtual braces using a patient-specific finite element model (FEM) and to analyze the most influential design factors. The 3D geometry of three patients presenting different types of curves was acquired with a multi-view X-ray technique and surface topography. A personalized FEM of the patients’ trunk and a parametric model of a virtual custom-fit brace were then created. The installation of the braces on the patients was simulated. The influence of 15 design factors on the 3D correction generated by the brace was evaluated following a design of experiments simulation protocol allowing computing the main and two-way interaction effects of the design factors. A total of 12,288 different braces were tested. Results showed a great variability of the braces effectiveness. Of the 15 design factors investigated, according to the 2 modalities chosen for each one, the 5 most influential design factors were the position of the brace opening (posterior vs. anterior), the strap tension, the trochanter extension side, the lordosis design and the rigid shell shape. The position of the brace opening modified the correction mechanism. The trochanter extension position influenced the efficiency of the thoracic and lumbar pads by modifying their lever arm. Increasing the strap tension improved corrections of coronal curves. The lordosis design had an influence in the sagittal plane but not in the coronal plane. This study could help to better understand the brace biomechanics and to rationalize and optimize their design.     

Hip joint kinematics and segment coordination variability according to pain and structural disease severity in hip osteoarthritis

This study aimed to evaluate hip joint kinematic variability and segment coordination variability during walking according to pain and radiographic disease severity in people with hip osteoarthritis. Fifty-five participants with hip osteoarthritis had pain severity assessed during walking using an item on the Western Ontario and McMasters Universities Osteoarthritis Index (no pain = 10; mild pain = 28; moderate pain = 17). Radiographic disease severity was graded by Kellgren and Lawrence scale (KL2 = 29; KL3 = 21; KL4 = 5). Hip kinematics variability was estimated as the curve coefficient of variation. Vector coding was used to calculate coordination variability for select joint couplings. One-way analysis of variances with planned adjusted post hoc comparisons were used to compare hip kinematics variability and coordination variability of select segment couplings (pelvis sagittal vs thigh sagittal; pelvis frontal vs thigh frontal; pelvis transverse vs thigh transverse; thigh sagittal vs shank sagittal; thigh frontal vs shank sagittal; thigh transverse vs shank sagittal) according to pain and radiographic disease severity. No main effect of pain severity was observed for sagittal or transverse plane hip kinematic variability (P ≥ .266), and although there was a main effect for frontal plane hip kinematic variability (P = .035), there were no significant differences when comparing between levels of pain severity (P > .006). There was no main effect of radiographic disease severity on hip kinematic variability in the sagittal (P = .539) or frontal (P = .307) plane. No significant differences in coordination of variability of segment couplings were observed (all P ≥ .229). Movement variability as assessed in this study did not differ according to pain severity during walking or radiographic disease severity.     

Deuxieme Congres De La Socictc Internationace De Chirurgle Orthopcdique

Background and purpose In 2002–2003, several hospitals in Norway introduced the Ponseti method for treating clubfoot. The present multicenter study was conducted to evaluate the initial results of this method, and to compare them to the good results reported in the literature.

Patients and methods 116 children with 162 congenital idiopathic clubfeet who were born between 2004 and 2006 were treated with the Ponseti method at 8 hospitals in Norway. All children were prospectively registered at birth, and 116 feet were assessed according to Pirani before treatment was started. 63% used a standard bilateral foot abduction brace, and 32% used a unilateral above-the-knee brace. One of the authors examined all feet at a mean age of 4 years. At follow-up, all feet were assessed by Pirani’s scoring system, and range of motion of the foot and ankle was measured.

Results At follow-up, 77% of the feet had a Pirani score of 0.5 or better, good dorsiflexion and external rotation, and no forefoot adduction. An Achilles tenotomy had been performed in 79% of the feet. Compliance to any brace was good; only 7% were defined as non-compliant. Extensive soft tissue release had been performed in 3% of the feet.

We found no statistically significant differences between the two braces, except a tendency of better Pirani score in the group using the bilateral foot abduction brace, and a tendency of better compliance in patients using the unilateral brace. Better Pirani scores were found in children who were treated at the largest hospitals.

Interpretation After introducing the Ponseti method in Norway, the clinical outcome was good and in accordance with the reports from single centers. Only 5 feet needed extensive surgery during the first 4 years of life.     

Proposal of New Radiological Classification and Treatment Strategy for Transverse Fractures of the C2 Axis Body

ObjectiveTo investigate the characteristics of transverse fractures of the C2 axis body diagnosed on sagittal computed tomography (CT) and to propose new classification and appropriate treatment strategies.MethodsA retrospective study was performed by enrolling 49 patients (26 men and 23 women) with transverse fractures of the C2 axis body who were treated at four national trauma centers of tertiary university hospitals from January 2000 to December 2017. The mean age of the patients was 60.8 years (ranging from 21 to 90 years). We classified 49 transverse fractures of the C2 body into three types based on fracture trajectories involving superior articular facet (SAF) and lateral cortex (LC) of the C2 body on coronal CT as follows: Type 1, involvement of C2 SAF on both sides; Type 2, unilateral involvement of C2 SAF on one side and LC on the other side; Type 3, involvement of LC on both sides. The characteristics, treatment methods, and results of 49 transverse fractures of the C2 body were analyzed. Mean follow‐up was 12.6 months (ranging from 12 to 26 months).ResultsTwenty‐six (53.1%) patients were Type 1, 21 (42.9%) were Type 2, and 2 (4.0%) were Type 3. Correlation coefficients for intra‐observer and inter‐observer reliabilities of classification were 0.723 and 0.598 (both, P < 0.001), respectively. About 40.8% (7 Type 1 and 13 Type 2) of the patients had fracture displacement >3 mm; Incidence of fracture displacement >3 mm was higher in Type 2 than Type 1 (61.9% vs 26.9%, P < 0.05). About 79.6% (20 Type 1, 17 Type 2 and 2 Type 3) of the patients were treated conservatively, and 20.4% (6 Type 1 and 4 Type 2) underwent surgery. At last follow‐up, 47 out of 49 patients achieved fusion; overall fusion rate was 95.9%. All conservatively treated Type 1 and Type 3 patients achieved fusion. Out of 17 conservatively treated Type 2 patients, 15 achieved fusion but two developed nonunion; however, two nonunion patients opted not to undergo surgery. Subgroup analysis showed that Philadelphia brace caused nonunion significantly in fracture displacement >3 mm compared to Minerva brace/Halovest (100% vs 0%, P < 0.05). All surgically treated Type 1 and 2 patients achieved fusion. In terms of clinical outcomes, neck pain visual analog scale and neck disability index were significantly improved (both, P < 0.01). According to Odom''s criteria, 93.9% (46/49) of the patients achieved satisfactory outcomes. No major complications occurred.ConclusionsThe majority of transverse fractures of C2 body can be treated conservatively. However, surgery or rigid Minerva brace/Halovest should be considered for Type 2 transverse fractures of the C2 body with fracture displacement >3 mm.     

Clinical and radiological outcomes of conservative treatment for unilateral sagittal split fractures of C1 lateral mass

ObjectiveThe aim of this study was to assess the effect of transverse atlantal ligament (TAL) integrity on clinical and radiological outcomes in patients with unilateral sagittal split fracture (USSF) of the C1 lateral mass (LM).MethodsTwenty-six consecutive patients (16 men and 10 women; mean age: 52 years (range: 32–69)) with C1 LM USSF were included in this study. Sixteen were TAL injury group (nine of type I injuries and seven of type II injuries according to Dickman's classification) and ten were TAL intact group. All cases were conservatively treated with a rigid brace for TAL intact or by halo-vest stabilization for TAL injury for three months. The mean follow-up was 16 months (range, 12–47 months). The results were compared with radiological assessment of fracture healing, LM displacement and Neck visual analog scale.ResultsAt the last follow-up, for TAL intact group, total LM displacement (LMD), unilateral LMD of fracture side, atlanto-dental interval, basion-dental interval, clivus canal angle, and atlanto-occipital joint axis angle were maintained compared to initial presentation. However, for TAL injury group, all radiological parameters were worsened. The worsening of radiological parameters was more severe in type I injury than type II injury except for total LMD and unilateral LMD. Neck visual analog scale significantly decreased and patient's satisfaction was higher in TAL intact group compared to TAL injury group.ConclusionConservative treatment for USSF of C1 LM with TAL injury failed to achieve healing of the fracture, which resulted in lateral displacement of C1 LM. This caused coronal and sagittal malalignment of occipitocervical junction, resulting in unsatisfactory clinical outcomes. Our results suggest that early surgical stabilization should be considered in USSF of C1 LM with TAL injury, especially type I injury. However, conservative treatment may be sufficient for a USSF of the C1 LM with TAL intact.Level of EvidenceLevel III, Therapeutic Study.     

Lumbar spine orthosis wearing. I. Restriction of gross body motions

The effects of wearing commonly prescribed low-back braces and corsets on restriction of gross body motions were investigated. A lumbosacral corset, a chairback brace, and a molded plastic thoracolumbosacral orthosis (TLSO) were studied. Four trunk movements (flexion, extension, lateral bending, and twisting) were examined in five healthy adult men when standing and sitting. All three orthoses restricted at least some gross body motion to approximately two thirds to one half of no-orthosis values. All three orthoses failed to provide restrictions of at least 10% in at least one motion. Mean motion restriction across all eight movements studied in all five subjects were largest when wearing the TLSO and least when wearing the corset. Gross body motion restrictions relieve lumbar trunk muscle and spine loads.     

Pedicle subtraction osteotomies (PSO) in the lumbar spine for sagittal deformities

Introduction

The narrow correlation between sagittal alignment parameters and clinical outcomes has been widely established, demonstrating that improper sagittal alignment is a clinical condition that is associated with increased pain and limitations in patients’ functional ability.

Indication

Lumbar pedicle subtraction osteotomy (PSO) is indicated in the treatment of large sagittal (more than 25° of rigid loss of lordosis) deformities of the lumbar spine or its combination with coronal deformity, especially when they are rigid. Indication should be based on careful assessment of the severity of symptoms, functional impairment, functional expectations of the patient, general clinical condition and surgical and anesthesiological team experience. Risk should be carefully assessed and discussed to obtain appropriate informed consent.

Surgical procedure

Surgical planning includes selection of the safest levels for the upper and lower instrumented vertebra, site of the osteotomy, modality of fixation, and, most importantly angular value of the correction goal (target lumbar lordosis). Failure to adequately obtain the necessary amount of sagittal correction is the most frequent cause of failure and reoperation.

Conclusion

PSO is a valuable surgical procedure in correction of severe hypolordosis (=relative kyphosis) in the lumbar spine. It is a demanding procedure for the surgeon, the anesthesiologist and the intensive care team. Although its complication rate is high, it has a substantial positive impact in the quality of life of patients, including the elderly.

     

The Effect of Postural Pelvic Dynamics on the Three-dimensional Orientation of the Acetabular Cup in THA Is Patient Specific

BackgroundSagittal pelvic dynamics mainly consist of the pelvis rotating anteriorly or posteriorly while the hips flexes, and this affects the femoroacetabular or THA configuration. Thus far, it is unknown how the acetabular cup of the THA in the individual patient reorients with changing sagittal pelvic dynamics.Questions/purposesThe aim of this study was to validate a method that establishes the three-dimensional (3-D) acetabular cup orientation with changing sagittal pelvic dynamics and describe these changes during functional pelvic dynamics.MethodsA novel trigonometric mathematical model, which was incorporated into an easy-to-use tool, was tested. The model connected sagittal tilt, transverse version, and coronal inclination of the acetabular cup during sagittal pelvic tilt. Furthermore, the effect of sagittal pelvic tilt on the 3-D reorientation of acetabular cups was simulated for cups with different initial positions. Twelve pelvic CT images of patients who underwent THA were taken and rotated around the hip axis to different degrees of anterior and posterior sagittal pelvic tilt (± 30°) to simulate functional pelvic tilt in various body positions. For each simulated pelvic tilt, the transverse version and coronal inclination of the cup were manually measured and compared with those measured in a mathematical model in which the 3-D cup positions were calculated. Next, this model was applied to different acetabular cup positions to simulate the effect of sagittal pelvic dynamics on the 3-D orientation of the acetabular cup in the coronal and transverse plane. After pelvic tilt was applied, the intraclass correlation coefficients of 108 measured and calculated coronal and transverse cup orientation angles were 0.963 and 0.990, respectively, validating the clinical use of the mathematical model.ResultsThe changes in 3-D acetabular cup orientation by functional pelvic tilt differed substantially between cups with different initial positions; the change in transverse version was much more pronounced in cups with low coronal inclination (from 50° to -29°) during functional pelvic tilt than in cups with a normal coronal inclination (from 39° to -11°) or high coronal inclination (from 31° to 2°). However, changes in coronal inclination were more pronounced in acetabular cups with high transverse version.ConclusionUsing a simple algorithm to determine the dynamic 3-D reorientation of the acetabular cup during functional sagittal pelvic tilt, we demonstrated that the 3-D effect of functional pelvic tilt is specific to the initial acetabular cup orientation and thus per THA patient.Clinical RelevanceFuture studies concerning THA (in)stability should not only include the initial acetabular cup orientation, but also they need to incorporate the effect of sagittal pelvic dynamics on the individual 3-D acetabular cup orientation. Clinicians can also use the developed tool, www.3d-hip.com, to calculate the acetabular cup’s orientation in other instances, such as for patients with spinopelvic imbalance.