MAGNA++: Maximizing Accuracy in Global Network Alignment via both node and edge conservation.

MOTIVATION: Network alignment aims to find conserved regions between different networks. Existing methods aim to maximize total similarity over all aligned nodes (i.e. node conservation). Then, they evaluate alignment quality by measuring the amount of conserved edges, but only after the alignment is constructed. Thus, we recently introduced MAGNA (Maximizing Accuracy in Global Network Alignment) to directly maximize edge conservation while producing alignments and showed its superiority over the existing methods. Here, we extend the original MAGNA with several important algorithmic advances into a new MAGNA++ framework. RESULTS: MAGNA++ introduces several novelties: (i) it simultaneously maximizes any one of three different measures of edge conservation (including our recent superior [Formula: see text] measure) and any desired node conservation measure, which further improves alignment quality compared with maximizing only node conservation or only edge conservation; (ii) it speeds up the original MAGNA algorithm by parallelizing it to automatically use all available resources, as well as by reimplementing the edge conservation measures more efficiently; (iii) it provides a friendly graphical user interface for easy use by domain (e.g. biological) scientists; and (iv) at the same time, MAGNA++ offers source code for easy extensibility by computational scientists. AVAILABILITY AND IMPLEMENTATION: http://www.nd.edu/∼cone/MAGNA++/

The Baumann procedure to correct equinus gait in children with diplegic cerebral palsy: long-term results.

Although equinus gait is the most common abnormality in children with spastic cerebral palsy (CP) there is no consistency in recommendations for treatment, and evidence for best practice is lacking. The Baumann procedure allows selective fractional lengthening of the gastrocnemii and soleus muscles but the long-term outcome is not known. We followed a group of 18 children (21 limbs) with diplegic CP for ten years using three-dimensional instrumented gait analysis. The kinematic parameters of the ankle joint improved significantly following this procedure and were maintained until the end of follow-up. We observed a normalisation of the timing of the key kinematic and kinetic parameters, and an increase in the maximum generation of power of the ankle. There was a low rate of overcorrection (9.5%, n = 2), and a rate of recurrent equinus similar to that found with other techniques (23.8%, n = 5). As the procedure does not impair the muscle architecture, and allows for selective correction of the contracted gastrocnemii and soleus, it may be recommended as the preferred method for correction of a mild fixed equinus deformity.

Comparison of conventional versus minimally invasive extraperitoneal approach for anterior lumbar interbody fusion.

The purpose of the study was to compare conventional versus minimally invasive extraperitoneal approach for anterior lumbar interbody fusion (ALIF). Fifty-six consecutive patients with spondylolisthesis, lumbar instability, or failed back syndrome were treated with ALIF between 1991 and 2001. The patients were retrospectively evaluated and divided in two groups: Group 1, consisting 33 patients, was treated with ALIF using the conventional retroperitoneal approach, and Group 2, consisting of 23 patients, was operated with the minimally invasive muscle-splitting approach for ALIF. The groups were comparable as regards age, indication of fusion, and diagnosis. All patients in both groups had fusion with autologous iliac crest grafts and posterior instrumentation with posterolateral fusion in the same sitting. Clinical evaluation was done by two questionnaires: the North American Spine Society (NASS) Lumbar Spine Outcome Assessment Instrument and the Nottingham Health Profile (NHP). Fusion rate was evaluated radiologically. Mean clinical follow-up was 5.5 years. There was no statistical difference in the occurrence of complications with both approaches nor with the fusion rates of 92% in group 1 and 84% in group 2 respectively. The minimally invasive extraperitoneal approach for ALIF was associated with significantly less intraoperative blood loss, operation time, and length of the skin incision. In addition, this approach showed significant improvement in postoperative back pain in comparison to the conventional approach for ALIF.

[Single event multilevel surgery to improve gait in diplegic cerebral palsy - a prospective controlled trial]. / Operative Mehretageneingriffe zur Gangverbesserung bei spastischer Diplegie - Eine prospektive kontrollierte Untersuchung1.

AIM: To evaluate prospectively the outcome of gait-improvement surgery in children with spastic diplegia. METHOD: Three-dimensional gait analysis was performed in twenty children with spastic diplegia. Ten children underwent single event multilevel surgery for gait improvement. Indications for individual procedures followed a fixed set of selection criteria. The other ten children continued with their physiotherapy programme and served as a control group. A second gait analysis was performed in all children after 1.5 years. Time-distance parameters and kinematics of the pelvis, hip, knee and ankle joints in the sagittal plane served as main outcome measures RESULTS: The patients walked faster with an increased stride length after surgery in comparison to the conservatively treated controls. The average pelvic tilt increased slightly and the range of motion of the knee joint increased considerably after multilevel surgery. The motion at the ankle remained unchanged over the study period in both the groups. An improved knee extension during the stance phase of gait served to improve stance limb stability and facilitated an unhindered swing phase of the opposite limb. CONCLUSION: This prospective trial showed favourable changes in gait function after multilevel surgery in spastic diplegic children.

Conservative management of dynamic equinus in diplegic children treated by gait improvement surgery.

Multilevel surgery for gait improvement was performed on twelve ambulatory children with diplegic type of cerebral palsy and dynamic equinus deformity. Dynamic equinus deformities were defined as those who had an equinus at initial contact during preoperative gait analysis, and where the equinus deformity was correctable passively during physical examination. Ankle function was evaluated by clinical examination and gait analysis before surgery, and at least 3 years after surgery. The ankle showed an increase in dorsal flexion at initial contact, at single stance and in swing. There was an increase in dorsal flexion at the beginning of push-off, without a decrease in the range of motion of the ankle during push-off. Ankle moments demonstrated significant improvement in the maximum flexor moment in the second half of single stance. There was a change from abnormal generation of the energy in mid-stance to the normal pattern of energy absorption. Positive work during push-off was significantly increased. Conservative management of dynamic equinus deformities combined with multilevel surgery to correct other deformities of the locomotion system resulted in significant improvements in ankle function during gait.

Propulsive function during gait in diplegic children: evaluation after surgery for gait improvement.

Seventeen patients with diplegic cerebral palsy were assessed by clinical examination and three-dimensional gait analysis before and after surgery to improve gait. Selection of surgical procedures was according to a fixed set of selection criteria. The average postoperative follow-up was 3.8 years (range, 2.6-5.7 years). Clinical examination revealed an improved range of motion for the ankle and no reduction in the power grade at the hip, knee and ankle after surgery. Kinematic parameters showed improved knee extension in stance and significant changes towards a normal ankle motion pattern postoperatively. Kinetic evaluation demonstrated that most of the total power during walking was generated at the hip, with the ankle contributing a small part. After surgery, patients walked faster with an increased power generation at the hip during first double support and at the ankle during push off. Power generation at the hip in stance is pointed out to be an important mechanism for propulsion during walking.

Hip locomotion mechanisms in cerebral palsy crouch gait.

The purpose of this study was to evaluate three defined locomotion patterns in cerebral palsy gait using computerised gait analysis. Ambulant diplegic children who had no previous surgery were included in the study and were divided into two groups: one group consisted of children having a crouch gait, and the other group did not have the crouch pattern of gait. An age-matched group of normal children served as the control group. Locomotion patterns studied were the hip hike, propulsive function of the hip extensors, and pseudo-adduction. A statistical analysis was performed between the groups, using defined parameters. The mechanism of hip hike was not utilised by any of the groups. Both groups of diplegic children showed power generation at the hip beginning in the first double support phase of the gait cycle and continuing in the first half of single limb support, while in the normals this was only in the first half of single limb support. Both the groups of diplegic children showed significantly more internal rotation in the first half of stance as compared to the group of normal children; the degree of hip adduction was the same in all the groups. Thus diplegic children had pseudo-adduction.

Fixed and dynamic equinus in cerebral palsy: evaluation of ankle function after multilevel surgery.

Multilevel surgery for gait improvement was performed on 29 ambulatory children with diplegic cerebral palsy. Patients were divided into two groups based on the presence of dynamic equinus (12 cases) and fixed equinus deformity (17 cases). Dynamic equinus deformities were not corrected surgically, and fixed deformities were corrected by intramuscular gastrosoleus lengthening. Ankle function was evaluated by clinical examination and gait analysis before surgery and a minimum of 3 years after surgery. Positive changes in ankle function were observed in both the groups. Conservative management of dynamic equinus deformities resulted in significant improvements in ankle function. Intramuscular lengthening of fixed equinus deformities does not cause a weakening of the muscle and improves static and dynamic function of the ankle.

Complex foot deformities associated with soft-tissue scarring in children.

Two cases of deformities in scarred feet are presented. One case had an old, well healed forefoot amputation with severe equinovarus deformity, and the other had an equinus deformity following a burn injury 10 months prior. Both the cases were managed by primary release of the contracted joint capsules. The correction of the soft-tissue contractures was achieved by gradual distraction using the Ilizarov apparatus. The clinical presentation and surgical treatment of complex foot deformities, complicated by the presence of scar tissue, are presented. These cases illustrate the benefits of combining soft-tissue release with the Ilizarov technique of distraction histogenesis in the treatment of complicated foot deformities associated with scarring in pediatric patients.

Flexible intramedullary nailing for the treatment of unicameral bone cysts in long bones.

BACKGROUND: Unicameral bone cyst is characterized by its tenacity and risk of recurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of flexible intramedullary nailing for the treatment of a unicameral bone cyst with or without a pathological fracture. METHODS: Flexible intramedullary nailing for the treatment of a unicameral bone cyst was performed in thirty-two patients. Thirty of these patients presented with a pathological fracture; twenty-four were managed immediately with intramedullary nailing, and the other six had been managed conservatively at other clinics before they were referred to our department. The remaining two cysts were detected incidentally. The cyst was located in the humerus in twenty-one patients, in the femur in nine, and in the radius in two. The mean age of the patients at the time of surgery was 9.8 years, and the mean duration of follow-up was 53.7 months. Radiographic evaluation was performed according to the criteria of Capanna et al., and the cyst was classified as completely healed, healed with residual radiolucency (osteolysis), recurred, or having no response. RESULTS: The healing period ranged from three to 105 months. Fourteen cysts healed completely, and sixteen healed with residual radiolucent areas visible on radiographs. There was recurrence of two cysts that had healed with residual radiolucency. All of the cysts in the present study responded to treatment. A change of nails was necessary in nine patients, as the nails had become too short after bone growth. No major complications were observed. CONCLUSIONS: Flexible intramedullary nailing provides early stability, which allows early mobilization and thus obviates the need for a plaster cast and decreases the prevalence of the most common complication: a pathological fracture. This method of treatment also allows for an early return to normal activity.

Assessment of hip rotation after gait improvement surgery in cerebral palsy.

Sixteen children with diplegic type of cerebral palsy and spastic internal rotation gait were evaluated using gait analysis before and an average of 3 years after multiple soft tissue surgery. Significant correction of the internal rotation gait was observed after multi-level soft tissue surgery which included medial hamstring lengthening in all cases. Our results suggest that for children with spastic internal rotation gait, multi-level soft tissue surgery effectively corrects the dynamic internal rotation gait in the absence of fixed bony rotational deformities.

The Baumann procedure for fixed contracture of the gastrosoleus in cerebral palsy. Evaluation of function of the ankle after multilevel surgery.

We treated 22 children (28 limbs) with diplegic cerebral palsy who were able to walk by the Baumann procedure for correction of fixed contracture of the gastrosoleus as part of multilevel single-stage surgery to improve gait. The function of the ankle was assessed by clinical examination and gait analysis before and at two years (2.1 to 4.0) after operation. At follow-up the ankle showed an increase in dorsiflexion at initial contact, in single stance and in the swing phase. There was an increase in dorsiflexion at initial push-off without a decrease in the range of movement of the ankle, and a significant improvement in the maximum flexor moment in the ankle in the second half of single stance. There was also a change from abnormal generation of energy in mid-stance to the normal pattern of energy absorption. Positive work during push-off was significantly increased. Lengthening of the gastrocnemius fascia by the Baumann procedure improved the function of the ankle significantly, and did not result in weakening of the triceps surae. We discuss the anatomical and mechanical merits of the procedure.

Intrasubject repeatability of gait analysis data in normal and spastic children.

OBJECTIVE: To evaluate intrasubject repeatability of data obtained from computer-aided motion analysis in normal and spastic children. DESIGN: Prospective controlled study. BACKGROUND: Information from gait analysis is used in selecting therapeutic interventions for gait improvement in cerebral palsy. While there are several studies regarding repeatability of normal gait, there are no studies evaluating the repeatability of spastic gait. METHODS: Forty children (20 normal, 20 with diplegic type of cerebral palsy) were subjected to gait analysis. Kinematic, kinetic and time distance parameters obtained from gait analysis were studied for intrasubject variability within-day and between-day using statistical measures. RESULTS: Normal children had lower variability in time distance parameters than spastic children both within and between days. The repeatability of kinetics was better than those of kinematics, and values for normal children were better than those for spastic children. Within-day repeatability of kinematics and kinetics was better in normal children. Between-day repeatability of kinematics was better in normal children, while spastic children showed better repeatability for kinetics. CONCLUSIONS: We found lower repeatability of gait analysis data in spastic children compared to normal children. Restricted joint range of motion due to spasticity in the group of cerebral palsy patients may be responsible for the lower repeatability of data. Some errors due to marker placement are inadvertent and contribute to the lower between-day repeatability. RELEVANCE: The results of this study should be of interest to clinicians who make therapeutic decisions in patients with cerebral palsy using gait analysis data, and for scientists studying normal and pathological gait.