Leg Manipulation Research Articles

Trans-Table Intraoperative Fluoroscopic Technique for Obtaining a True Lateral View of the Proximal Femur in the Lateral Decubitus Position.

The management of proximal femoral fractures, especially comminuted subtrochanteric ones, poses a surgical challenge. It is relatively easier to perform the open reduction of these fractures in the lateral position on a standard radiolucent table, but obtaining an accurate lateral view of the femoral head and neck remains difficult. This study presents a method that overcomes the limitations of fluoroscopy in the lateral decubitus position and improves the accuracy of obtaining a true lateral view. The technique involves positioning the patient in the lateral decubitus position with the unaffected hip flexed at a 45° angle. Additionally, the C-arm is tilted 30-35° cephalad, eliminating the need for position changes or leg manipulation. This method reduces the risk of losing reduction, particularly in cases involving obese patients or complex fractures. By simplifying proximal femur fixation in the lateral decubitus position, this technique can potentially improve patient outcomes.

Kinematic Model of the Human Leg Using DH Parameters

Robotic-assisted surgical procedures have recently increased in popularity in clinical environments. Applications of clinically approved surgical robots range from minimally invasive surgery to open joint replacements. In hip and knee orthopaedic procedures, access to leg joint cavities require constant manipulation of the patient's leg to a high degree of accuracy to reduce surgical injuries. This study develops a nine degree of freedom serial kinematic model of the human leg, using the well known Denavit Hartenberg Parameters, for robotic-assisted leg manipulation during orthopaedic leg surgery. The proposed model is validated through human cadaver experiments with an optical tracking system used as ground-truth to measure the leg pose. The knee and foot workspace for the model determines the pose of the leg and in comparing it to cadaver leg position. The positional error relative to the cadaver leg was found to be 0.43mm and 0.4mm respectively, with a maximum uncertainty of 3.51mm in the foot position. It demonstrates that the proposed model provides an accurate representation of the human leg motion for automated leg manipulation during orthopaedic surgery.

Anatomical Joint Measurement With Application to Medical Robotics

Robotic-assisted orthopaedic procedures demand accurate spatial joint measurements. Tracking of human joint motion is challenging in many applications, such as in sport motion analyses. In orthopaedic surgery, these challenges are even more prevalent, where small errors may cause iatrogenic damage in patients – highlighting the need for robust and precise joint and instrument tracking methods. In this study, we present a novel kinematic modelling approach to track any anatomical points on the femur and / or tibia by exploiting optical tracking measurements combined with a priori computed tomography information. The framework supports simultaneous tracking of anatomical positions, from which we calculate the pose of the leg (joint angles and translations of both the hip and knee joints) and of each of the surgical instruments. Experimental validation on cadaveric data shows that our method is capable of measuring these anatomical regions with sub-millimetre accuracy, with a maximum joint angle uncertainty of ±0.47°. This study is a fundamental step in robotic orthopaedic research, which can be used as a ground-truth for future research such as automating leg manipulation in orthopaedic procedures.

Pilot study of the impact sacroiliac joint manipulation has on walking kinematics using motion analysis technology

ObjectiveThe purpose of this study was to evaluate the feasibility of engaging in a series of larger studies measuring the effect of sacroiliac joint manipulation on walking kinematics using motion analysis technology. MethodsTwelve college students engaged in a baseline 90-second gait analysis at 1.5 mph using infrared VICON cameras. Following this, they underwent a prone heel comparison test for functional leg length inequality. Upon examination, participants were then classified as follows: left short leg, right short leg, or no short leg. Participants in each of the 2 short leg branches of this study were then randomized to receive either chiropractic manipulative therapy to the posterior superior iliac spine on the short limb side or no manipulation. Recruitment was ongoing for this pilot study until 1 participant was recruited in each of the following 5 comparative study groups: left short leg—manipulation, left short leg—no manipulation (control 1), right short leg—manipulation, right short leg—no manipulation (control 2), and no short leg (control 3). All participants then underwent another 90-second gait analysis. Data were then grouped and submitted to a blinded biomechanist to determine if there were any unique biomechanical differences between the groups. ResultsNo statistically significant differences were measured because of this being a pilot study with a small sample size. ConclusionsThe data from this study indicate that a series of larger studies with this design is feasible.

Infant With Right Leg Swelling, Tenderness, and Decreased Range of Motion

A 9-day-old girl, delivered at 39 weeks’ gestation via cesarean delivery for footling breech position, presented with right leg swelling, tenderness, and decreased range of motion since birth (Figure 1). ### Prenatal and Birth Histories The patient was afebrile, nippling well, and alert after delivery. However, patient's parents stated that her right leg was “swollen and not moving” since birth. Mother stated infant became very fussy during leg manipulation and diaper changes. Parents say they spoke to the nurse at the birth hospital and were told this is a normal result of breech presentation. The parents deny any history of trauma. The mother denies the infant has experienced any vomiting, diarrhea, bloody stools, apnea, or seizure activity. Parents state they took the child to her pediatrician on day 7 after birth for her newborn check and told the pediatrician about the leg. They were instructed to go to the emergency department. Parents went to emergency department that evening, and the child was admitted for overnight observation and then transferred to Children’s Hospital of Michigan NICU the next day to investigate child abuse. ### Social History Patient's parents were living with paternal grandmother. Patient's 30-year-old father stated that he has 3 other children (ages 6, 8, and 11 years), none of whom he has custody. Patient's father states he lost custody of his children because he was “young.” ### Vital Signs ### Physical Examination

Mechanical effects of leg position on vertebral structures examined by magnetic resonance imaging

Background and Objectives: Leg manipulation has been postulated to affect spinal curvature and position of the cauda equina within the dural sac. However, no evidence of such mechanical effects has been shown in living subjects. We used magnetic resonance imaging to evaluate the mechanical effects of leg position on these 2 parameters. Methods: Sagittal and axial magnetic resonance images of the lumbosacral vertebral canal were obtained in 5 healthy, female volunteers with the subject in the supine position with knees straight, knees slightly flexed, and knees fully flexed. Results: In the straight leg position, physiologic lumbar lordosis was evident in all subjects on midline sagittal slices, whereas lumbar lordosis disappeared in the fully flexed leg position. On the axial slices the cauda equina moved ventrally within the dural sac in all subjects in the fully flexed leg position. In 1 of the 5 subjects the cauda equina moved ventrally and also separated completely into right and left parts. Conclusions: Our findings indicate that 2 potential factors, flattening of the lumbar lordosis and some added tension on the lumbosacral nerve roots, may contribute to postoperative back and leg aching after spinal anesthesia in the lithotomy position. Reg Anesth Pain Med 2002;27:429-432.

A new fetal rat model of gastroschisis: Development and early characterization

The perinatal management and pathophysiology of gastroschisis remain controversial. Large animal experimental models of gastroschisis are inherently limited by expense and length of gestation, making multiple studies and statistical analysis difficult. To address these limitations the authors have developed a model of gastroschisis in the fetal rat. Twenty-one time-dated pregnant rats underwent laparotomy at 18 (1/2) day's gestational age. The exposed uterus was bathed in ritodrine for tocolysis. The right posterior leg was exteriorized through a hysterotomy, and under a dissecting microscope (16x) the fetal small bowel was exteriorized through a small incision performed on the right lower abdominal quadrant. The amniotic fluid was restored with saline solution and the hysterotomy closed with a purse-string suture. Control fetuses underwent hysterotomy and leg manipulation only. The surgical time was uniformly less than 60 minutes. Fetuses were harvested by cesarean section at 21 (1/2) days' gestational age. Fetal intestine was assessed by microscopic examination, and fetal weight, intestinal length, and intestinal weight per unit length were evaluated. There was a significant surgical and anesthetic learning curve, which is not included in this report. After this, the authors achieved a maternal survival of 100% (n = 21). We created gastroschisis in 64 fetuses (58 survivors, 90.6%), and 33 fetuses were only manipulated (30 survivors, 90.9%). The number of induced gastroschisis per pregnant rat varied between 2 and 5 with median of 3. On gross examination, eviscerated intestine appeared dilated, edematous, and covered by peel when compared with control intestine. Fetuses with gastroschisis had significantly reduced body weight (4.1+/-0.5 v 5.6 g +/- 0.5 g) and intestinal length (102+/-19 v 210+/-17 mm) relative to controls, whereas the intestinal weight per unit length (1.75+/-0.29 v 0.71 +/- 0.1 mg/mm) was markedly increased (P<.001). The pathophysiology observed in this experimental model appears to resemble human gastroschisis. In comparison with large animal models, the rat model offers the advantages of low expense, short gestation, littermate controls, and high maternal and fetal survival rates. In addition, there are specific probes and reagents available for application of molecular methodology to clarify the mechanisms responsible for the intestinal damage. This model appears appropriate for future experimental studies on gastroschisis.

Transient neurologic syndrome in one thousand forty-five patients after 3% lidocaine spinal anesthesia.

Recent reports have discussed the potential risk of transient radicular irritation (TRI) after spinal anesthesia with lidocaine. Because we have not encountered such neurologic sequelae with the high incidence reported, we prospectively examined the incidence of TRI after spinal anesthesia with lidocaine. One thousand forty-five adult patients (aged 47 +/- 15 yr) receiving spinal anesthesia with 3% hyperbaric lidocaine (1.0-1.5 mL) for anorectal surgery were consecutively studied. After the induction of spinal anesthesia, all patients were placed in the prone position for surgery. Patients were evaluated for neurologic symptoms in the buttocks, thighs, or lower extremities using a checklist to standardize data collection. Although there was no complaint of neurologic symptoms on Postoperative Day (POD) 1, four patients (0.4%) reported aching, hypesthesia, numbness, or dull pain of both lower extremities and buttocks by the morning of POD 3. In three patients, the symptoms resolved without any treatment by POD 5, whereas in one patient, numbness of the lower extremities lasted until POD 7. We conclude that a combination of lidocaine with surgical position or leg manipulation during surgery might be a major contributing factor in the development of transient neurologic syndrome. Recent studies have reported the potential risk of transient neurologic syndrome after lidocaine spinal anesthesia. The current study reports a low incidence of such sequelae in 1045 patients undergoing anorectal surgery during the prone position. Other factors, such as surgical position, may be important in the development of this syndrome.

Subdural hygroma: results of treatment by ventriculo-abdominal shunt.

Subdural hygromas, which differ from acute and chronic subdural haematomas in clinical features and pathogenetic mechanism, can occur as isolated lesions or in association with ventricular dilatation and/or subarachnoid cysts which are mistaken for atrophy. On the basis of the postulate that these fluid accumulations might be related to a disturbance in CSF circulation, we treated them by ventriculoperitoneal CSF drainage. This was regarded as indicated only for children with symptoms of retardation and a distended ventricular system. Disappearance of the hygroma or the cortical cysts and ventricular dilatation was demonstrated in 9 of 14 children treated by ventriculo-abdominal shunt and in 4 of 7 less seriously affected untreated children. Clinical improvement came later than neuroradiological improvement, and was incomplete in a number of children. Although there are anamnestic factors with an unfavourable effect on development, the hygromas per se can cause cerebral dysfunction which is associated with their bifrontal localization. The principal symptoms are those of retardation in the development of verbal expression, leg motor function and manipulation.