Scoliosis and BMI in patients with Prader-Willi syndrome.

Although scoliosis is commonly seen in patients with Prader-Willi syndrome, the patterns and extent of the deformity may change along their growth. Increased body weight is another issue in these patients, and its relationship with scoliosis is still controversial. The aim of this study was to evaluate scoliosis in patients with PWS, and its relationship with BMI. This was a retrospective cohort study in which a series of radiographic images and BMI from each patient were collected, and the data were rearranged following the age at which they were recorded. These patients were subsequently labeled as non-Scoliotic (<10°), Moderate (10° - 39°), and Severe (≥40°) according to their final Cobb angle, also as Normal (≤85%), Overweight (86%-95%), and Obese (≥95%) according to final BMI percentage. Thirty-four patients with age from 1 to 20 years old were recruited for this study, and the mean length of follow-up was 6.6 years. The prevalence of scoliosis was 71% (24 patients in Moderate, and 9 patients in Severe), and 65.6% were either overweight (11 patients) or obese (10 patients). The mean BMI percentage in non-scoliotic patients was 93.10 ± 13.84, which was significantly higher than that of the scoliotic groups ( P = 0.0180). When looking at the longitudinal change, the non-Scoliotic group had high BMI since childhood, and obese patients had less spine deformity also from early childhood. In this study, we found that the prevalence of scoliosis in Taiwanese population with PWS was 71% without gender preference. Not every patient had a high BMI, and obese patients seemed to have significantly less chance to develop scoliosis. Level III.

A robotized handheld smart tool for orthopedic surgery.

BACKGROUND: Handheld surgical robots offer functionalities, such as active guidance, tremor suppression and force reflection, for surgeons to enhance their skill in manipulating surgical tools during medical intervention. In orthopedic surgery, the robot additionally has to offer sufficient rigidity and power for bone machining. The size and weight of the mechanical design, together with the control behaviour associated with involuntary hand motion, navigation and reflected force to the human, all influence the overall performance of an orthopedic handheld robot. METHODS: The paper proposes a miniature and compact design for an embedded robot, which is a similar weight as a handpiece. Then, a shared controller is proposed to address the coupling among involuntary and voluntary hand motions, robot navigation, tool feedback forces and force artefacts from actuation. RESULTS: The handheld robot is able to stabilize the drill positioning by removing involuntary tremors as well as reduce force artefacts from motor actuation in experiments involving pedicle tunnelling on a porcine spine. CONCLUSION: The paper has successfully realized a compact handheld orthopedic robot which provides high performance of usability, tremor suppression and force reflection for bone drilling.

Endovascular intervention in Taiwanese patients with critical limb ischemia: patient outcomes in 333 consecutive limb procedures with a 3-year follow-up.

BACKGROUND/PURPOSE: Midterm outcomes of endovascular intervention (EVI) for critical limb ischemia (CLI) have not been previously reported in Taiwan. This study assessed the safety, feasibility, and patient-oriented outcomes for CLI patients after EVI. METHODS: From June 2005 to December 2011, 270 patients underwent EVI for CLI of 333 limbs. Primary patency (PP), assisted primary patency (AP), limb salvage, sustained clinical success (SCS), secondary SCS (SSCS), and survival were assessed using Kaplan-Meier analysis. RESULTS: The procedural success rate was 89%, and the periprocedural mortality and major complication rates within 30 days were 0.6% and 6.9%, respectively. During the mean follow-up time of 27 ± 20 months (1-77), 64 patients died and 25 legs required major amputation. Eighty-one percent of the patients with tissue loss had wound healing at 6 months and 75% of the patients were ambulatory, with or without assisting devices, at 1 year. The overall survival and limb salvage rates at 3 years were 70% and 90%, respectively. The PP and AP at 1 and 3 years were 58% and 37% and 79% and 61%, respectively. The SCS and SSCS were 65% and 46% and 80% and 64% at 1 and 3 years, respectively. CONCLUSION: In Taiwan, EVI was a safe and feasible procedure for CLI patients, with a high procedural success rate and lower complication rate. Sustained limb salvage and clinical success can be afforded with an active surveillance program and prompt intervention during midterm follow-up.

Coordinated control of bone cutting for a CT-free navigation robotic system in total knee arthroplasty.

BACKGROUND: Robots are gradually becoming intelligent tools for surgeons in computer assisted orthopedic surgery. A hands-on robot combining CT-free navigation software and coordinated control has been designed for total knee arthroplasty. METHODS: The hands-on robot is under bilateral force control so that the robot not only follows the force commands from the operator but also shapes the reflected force back to the operator. The proposed coordinated control also defines three operating modes to fulfill intelligent bone cutting by tuning appropriate scaling to the admittance gains. RESULTS: Experimental results demonstrated assistive, resistant and emergent actions to meet various bone cutting conditions by the coordinated controller. CONCLUSIONS: The proposed coordinated controller enables the robot to perform bone cutting more safely, rapidly and accurately compared with being performed by manual bone saw. The intelligent bone cutting has been successfully verified by a cadaver test.

Functional assessment of a surgical robot for reduction of lower limb fractures.

BACKGROUND: This paper presents a novel robot designed for reduction of lower limb fractures, with the additional features of automatic controlled flexion of the knee joint, individual traction of thigh and leg, and foot rotation. The aim of this design is to assist the orthopaedic surgeon to perform better fracture reduction through motor control, in contrast to current manual control, and the results of assessments of its functions on normal subjects are presented in this paper. METHODS: The robot was designed to be mounted onto the operation table, and was controlled through open switch relay. Functional assessments were conducted on six healthy volunteers in terms of knee joint motion and lower limb traction; measurement of angle and distance was calculated from data obtained by a 3D ultrasonic motion system (Zebris(®) ). RESULTS: The results showed a good correlation of the flexion angle between the robot and the subjects at the knee joint. In the traction tests, a steady lengthening of the proximal as well as the distal segment of the robot was observed, and a slight increase in subjects' limb length was also recorded, which might be due to distraction in the joint space. CONCLUSION: This automatic control fracture table has distinct features compared with the conventional ones, and it is believed to be of assistance to surgeons when performing fracture fixations.

Clinical application of rapid prototype model in pediatric proximal femoral corrective osteotomy.

Proximal femoral deformities can occur in children as sequelae of several disorders such as hip joint infection or avascular necrosis of the femoral head. Early surgical correction of deformities promises a good result; however, limited exposure of the surgical field often creates difficulties for surgeons. Application of a rapid prototyping model for proximal femoral corrective osteotomy in children serves not only as a guide for surgical planning but also as a communication tool between physicians and patients.

Extension splint for trigger thumb in children.

Sixty-two reducible trigger thumbs in 50 children with age from 0 to 4 years (mean, 1 year 11 months) were reviewed to study the effect of splinting. Thirty-one thumbs in 24 children received splinting for a mean of 11.7 weeks. The other 31 thumbs in 26 children were only observed. The results were categorized as cured, improved, or nonimproved. Follow-up was conducted after a mean of 20 months (age, 43 months). Result in the splinted group showed cured in 12 thumbs, improved in 10 thumbs, and nonimproved in 9 thumbs, whereas in the observed group, result showed 4, 3, and 24, respectively. Splinting results in 71% trigger thumbs cured or improved that is better than observation alone. The subsequent surgical release for the nonimproved trigger thumbs after splinting still had excellent results. Because surgical release for trigger thumb is not urgent, we suggest extension splinting to be a treatment option before the elective surgery.

Percutaneous screw fixation for unstable scaphoid fractures.

BACKGROUND: The technique of percutaneous screw fixation, with increasing popularity, has been successfully conducted in non-displaced, stable scaphoid fractures resulting in shortened immobilization duration and prompt functional retrieval. The purpose of this study was to evaluate the surgical technique and to explore the potential benefits of using percutaneous screw fixation in unstable scaphoid fractures. METHODS: Eleven of 97 patients with scaphoid fractures surgically treated between 1994 and 2002 were enrolled in this study. All were acute unstable fractures and underwent closed reduction and percutaneous screw fixation. All the records were meticulously reviewed and reported, including the complete radiographic examination before and after operation, time to fracture union, wrist motion, grip strength, and time of return to work, as well as overall patient satisfaction at the time of the most recent follow-up. RESULTS: Eleven fractures in an equal number of patients were followed up for a mean period of 1.6 years. All fractures acquired radiographic union in an average of 10.6 weeks. The modified Mayo Wrist score averaged 88.2. The functional result was ranked as excellent in 6 patients, and good in 5 patients. All returned to work or the pre-injury level of activity, and were satisfied with the surgical outcome. CONCLUSION: The technique of percutaneous screw fixation was successfully used to treat 11 unstable scaphoid fractures. The encouraging outcome of this treatment option and the prompt functional recovery deserve further investigation. Further randomized prospective studies to explore the specific indications and ubiquitous benefits of the technique presented herein are recommended.

Rush pin fixation versus traction and casting for femoral fracture in children older than seven years.

BACKGROUND: The optimal treatment for femoral fractures in children is controversial. The purpose of this study was to compare the results of Rush pin fixation with those of conservative treatment, and to evaluate the sequels of growth plate injury by internal fixation. METHODS: Eighteen femoral shaft fractures in 17 children who had concomitant head injury or multiple traumas were treated surgically. The mean age at operation was 9 years 3 months (range, 7 years 5 months to 11 years 1 month). One Rush pin was inserted from the tip of the greater trochanter, without reaming, to fix the fracture. Another 20 age-matched children treated by traction and casting were the control subjects. RESULTS: All the fractures united without consequences. In addition to a decrease in hospital stay with the use of the Rush pin (10 days vs. 27 days, p<0.05), fewer leg length discrepancies (4.2 mm vs. 7.1 mm, p<0.05) were also noted, compared with conservative treatment. The growth of the proximal femur after Rush pin fixation was evaluated after an average of 59 months. No femur shortening, coxa valgus, or hip dysplasia was noted. CONCLUSIONS: Intramedullary Rush pin fixation for femoral shaft fracture in children older than 7 years is a simple and reliable alternative. One narrow and non-reaming pin inserted from greater trochanter did not demonstrate femoral growth inhibition.

Acute primary hematogenous osteomyelitis of the epiphysis: report of two cases.

Acute primary infection of the epiphysis is uncommon. We present 2 cases of acute osteomyelitis of the distal femoral epiphysis. They were not diagnosed until 10 days and 3 weeks, respectively, after the onset of symptoms. The epiphyseal infection spread into the knee joint, and surgical debridement was performed. The majority of reported cases in the medical literature are of bacterial etiology, and the most common pathogen is Staphylococcus aureus. We report a rare case which was infected by Salmonella enteritidis. Prompt diagnosis and early treatment are required to prevent further destruction and growth disturbance.