Novel technique for craniospinal radiotherapy with patient supine

A simple procedure to plan, verify and implement craniospinal irradiation（CSI） with patients supine is presented. Treatment is conducted with a single posterior spinal field abutting two lateral cranial fields. The opposed lateral fields are half-blocked and the inferior line is perpendicular. The posterior field uses some fixed field parameters so that the cephalad edge of the posterior field is coplanar with the caudal edges of the lateral fields and it is independent of the height of the couch. A steel-shot ball is used to measure the size of overlap or gap at the junction using portal images of an electron portal image device or portal films. The results of analyzing the portal images show that the errors of the junction are within ± 1 mm. The dose-volume histograms （DVHs）show that there are not unbearable hot or cold spots in the clinic target volumes （CTVs）. Supine craniospinal treatment is a reliable and convenient alternative to treatment in the prone position and avoids the technical difficulties of the latter. The use of fixed field geometry greatly facilitates treatment planning and effectively reduces the amount of time of setup, verification and treatment.

Comparing maternal and neonatal outcomes between hands-and-knees delivery position and supine position

Background:The supine position is the most common birth position adopted in China,but the World Health Organization recommends non-supine positions for delivery.The handsand-knees position shows several advantages,such as wide pelvic diameter and easy fetal rotation during delivery.Small trials conducted in China in 2011 revealed that the handsand-knees position resulted in improved maternal and neonate outcomes than those in the supine position.However,a comprehensive study must be conducted before the handsand-knees position can be introduced into clinical practice.Hence,we conducted this multicenter trial to comprehensively examine the benefits of the hands-and-knees position over the supine position during delivery.Methods:Our clinical study was conducted in 11 hospitals in China from May to December 2012.A total of 446 pregnant women who gave birth in the hands-and-knees position were assigned into the experimental group,and 440 women who gave birth in the supine position were classified into the control group.Episiotomy rate was evaluated as the primary outcome,and perineum laceration degree was considered the secondary outcome.Results:Women in the experimental group achieved lower rates of episiotomy and higher rates of intact perineum and first-degree perineum lacerations compared with those in the control.Postpartum bleeding amount,neonatal asphyxia,and APGAR scores at 1 and 5 min were not significantly different between the two groups.Conclusions:This study proves that women who delivered in the hands-and-knees position achieved low rates of episiotomy and intact perineum.Moreover,the rates of neonatal asphyxia and postpartum bleeding did not increase.Pregnant patients who prefer to adopt the hands-and-knees position should be assisted in assuming such position during delivery.

Combined ab-interno trabeculectomy and cataract surgery induces comparable intraocular pressure reduction in supine and sitting positions

AIM:To analyze the therapeutic effect of combined abinterno trabeculectomy and cataract surgery on intraocular pressure(IOP)levels in supine and sitting postures during a 24-hour IOP profile.METHODS:Twenty-six eyes of twenty-six patients receiving ab-interno trabeculectomy using electroablation of the trabecular meshwork combined with cataract surgery or stand-alone were included in this retrospective analysis.IOP change during 24-hour IOP profiles within two years postoperatively were analyzed for eyes receiving surgery(“study eyes”)and compared to fellow eyes,which had not received surgery.Clinical data including mean sitting IOP(siIOP),mean supine IOP(su IOP)and the number of topical antiglaucomatous medications(TAM)were extracted from patients’files.RESULTS:Preoperatively,si IOP was 17.6±5.3 mm Hg in study and 17.1±4.7 mm Hg in fellow eyes(P=0.347).Patients were treated with an average of 2.8±1.0 TAM.Best corrected visual acuity(BCVA)was significantly worse in study eyes(P<0.001),visual field function was marginally not significantly dif ferent(P=0.057).Af ter surger y 9.6±6.8 mo,study eyes had a mean si IOP of 14.5±3.6 mm Hg(IOP reduction:-3.2 mm Hg,P=0.009),a mean su IOP of 18.0±3.5 mm Hg,and an average of 1.3±1.34 TAM(P<0.001),while in fellow eyes,mean si IOP was 16.2±3.4 mm Hg and mean su IOP was 20.5±5.1 mm Hg.Postoperatively,the relative IOP increase between sitting and supine postures was approximately 30%in both study and fellow eyes(P=0.99).CONCLUSION:IOP after ab-interno trabeculectomy shows a comparable relative reduction in both supine and sitting position.Classical trabeculectomy is known to lower su IOP overproportionally.

Comparisons of Supine Roll Test and Alternative Positional Tests in HC-BPPV Lateralization

Objective The purpose of the study was to evaluate the efficiency of the supine roll test(SRT)and alternative positional tests(APTs)including the bow and lean test(BLT),pseudo-spontaneous nystagmus(PSN),and lying down nystagmus(LDN)to identify the affected side in horizontal canal benign paroxysmal positional vertigo(HC-BPPV).Methods In our prospective study,we performed a testing profile(PSN,BLT,LDN,SRT)on 59 HC-BPPV patients using videonystagmography.We compared the accuracy and sensitivity of these tests in HC-BPPV lateralization.Data from 30 healthy patients were collected as the control group.Results When performing positional tests,the elicited nystagmus coinciding with Ewald’s second law was defined as a“positive response”.In 44 patients with geotropic nystagmus,the rates of positive response in LDN,PSN,and BLT were 22/44(50%),19/44(43%),and 18/44(41%),respectively,while in 15 patients with apogeotropic nystagmus,the positive response rates of these three tests were 10/15(66.7%),9/15(60%),and 4/15(27.00%),respectively.The sensitivity of LDN(54.38%)was higher than that of PSN(47.37%)and BLT(38.60%)but lower than that of SRT(89.47%).Notably,the accuracy rate of PSN(71.8%)was higher than that of the other APTs.In 6 patients with symmetrical nysgtamus during the roll test,5 patients showed a positive response in both LDN and BLT(83.34%),whereas 4 patients showed a positive response in PSN(66.67%).Conclusion All positional tests are helpful for determining the affected side of HC-BPPV,but SRT carries the highest accuracy of lateralization followed by PSN.

Evaluation of Partial Pressure of Arterial Oxygen in Obese Patients in Supine Position during General Anesthesia

Background: Anesthetists should measure the concentration of supplemental oxygen to determine whether patients’ partial pressure of arterial oxygen (PaO2) is correct during general anesthesia. However, the standard PaO2 value in obese patients in the supine position is unknown. We evaluated the PaO2 with respect to the Broca-Katsura obesity index. Materials and Methods: From January 2001 to December 2013, we evaluated 472 patients aged ≥16 years old that underwent general anesthesia in the supine position. The anesthetic charts of 472 patients with an American Society of Anesthesiologists physical status of I or II were retrospectively reviewed to investigate the PaO2. Results: In patients aged 16 to 2 was 165.7 ± 25.6 mmHg at a Broca-Katsura index of 2 was 152.1 ± 23.8 mmHg at a Broca-Katsura index of 2 tended to decrease with age from 16 to 2 tended to decrease with age from 16 to <65 years at a Broca-Katsura index of 20% to <40%.

Evaluation of Pressure of Arterial Oxygen by Age in Supine Position during General Anesthesia

Background: The concentration of supplemental O2 should be measured during general anesthesia to determine whether patients’ pressure of arterial oxygen (PaO2) is correct. Nevertheless, we do not know standard value of PaO2 by age in supine position during general anesthesia. In this study, we evaluated the PaO2 by age at 33% or 40% O2 concentration. Materials and Methods: We retrospectively reviewed the anesthetic charts of 660 patients who were received general anesthesia from January 2001 to December 2013. Patients were divided into two groups by concentration of fraction of inspiratory oxygen: group at 33% or 40%. Second, patients aged 16 - 85 years were classified into 7 groups by age with each group covering one decade. Results: The PaO2 was 185.1 ± 19.2 mmHg (33%) and 209.8 ± 19.8 mmHg (40%) at age 16 - 25 years, 178.7 ± 23.6 mmHg (33%) and 202.7 ± 26.0 mmHg (40%) at age 26 - 35 years, 165.8 ± 30.6 mmHg (33%) and 188.9 ± 22.2 (40%) mmHg at age 36 - 45 years, 154.1 ± 22.8 mmHg (33%) and 181.8 ± 19.2 (40%) mmHg at age 46 - 55 years, 153.7 ± 21.7 mmHg (33%) and 177.5 ± 18.1 mmHg (40%) at age 56 - 65 years, 152.2 ± 24.5 mmHg and 171.0 ± 22.1 mmHg at age 66 - 75 years, and 154.6 ± 24.3 mmHg and 174.1 ± 20.2 mmHg at age 76 - 85 years. Conclusion: The PaO2 tended to decrease with age at both 33% and 40% O2 concentration.

Comparison of the dose to lung volume between supine and prone position during treatment planning

Objective The aim of the study was to compare the dose to lung volume in the supine and prone posi- tion while designing CyberKnife treatment plans to treat metastatic tumors in the spinous processes of the thoracic vertebrae, and offer a reference for reducing damage to normal tissues. Methods Nine cases of metastatic tumors in the spinous processes of the thoracic vertebrae were selected, and then we designed treatment plans based on the supine and prone positions and compared the results. Results In contrast with the treatment plan based on the prone position, the one for the supine position required 14862-36337 MU more; the lung D5% was 5.20-7.90 Gy higher; and the lung D20% was 2.61-5.73 Gy higher. The difference of dose to spine volume between the two plans was -2.21-2.67 Gy; to the skin volume was -3.93-7.85 Gy; and to the esophagus was 0.28-6.39 Gy. Conclusion The treatment plan based on the prone position of patients can better protect lung tissues than the one based on the supine position, and can also improve the avaUabilitv of beams.

Hypothesis on supine sleep,sudden infant death syndrome reduction and association with increasing autism incidence

AIM:To identify a hypothesis on:Supine sleep,sudden infant death syndrome(SIDS) reduction and association with increasing autism incidence.METHODS:Literature was searched for autism spectrum disorder incidence time trends,with correlation of change-points matching supine sleep campaigns.A mechanistic model expanding the hypothesis was constructed based on further review of epidemiological and other literature on autism.RESULTS:In five countries(Denmark,United Kingdom,Australia,Israel,United States) with published time trends of autism,change-points coinciding with supine sleep campaigns were identified.The model proposes that supine sleep does not directly cause autism,but increases the likelihood of expression of a subset of autistic criteria in individuals with genetic susceptibility,thereby specifically increasing the incidence of autism without intellectual disability.CONCLUSION:Supine sleep is likely a physiological stressor,that does reduce SIDS,but at the cost of impact on emotional and social development in the population,a portion of which will be susceptible to,and consequently express autism.A re-evaluation of all benefits and harms of supine sleep is warranted.If the SIDS mechanism proposed and autism model presented can be verified,the research agenda may be better directed,in order to further decrease SIDS,and reduce autism incidence.

Arterial and End-Tidal Carbon Dioxide in Supine Obese Patients during General Anesthesia

Background: We investigated the differences between partial pressure of arterial carbon dioxide and end-tidal carbon dioxide (P(a-ET)CO2) with respect to the Broca-Katsura index (BKI), which is an obesity index, in obese patients during general anesthesia. Materials and Methods: From January 2003 to December 2013, we studied 601 patients aged 16 years old or over undergoing general anesthesia. Patients had American Society of Anesthesiology physical status I and II and we reviewed their anesthetic charts. The P(a-ET)CO2 with respect to the BKI divided patients into two groups: 16 to 2 values between the two groups. Results: In patients aged 16 to 2 was 2.2 ± 3.1 mmHg at BKI 2 was 3.2 ± 4.1 mmHg at BKI 2 tends to increase in obese patients during general anesthesia with increasing BKI in patients aged 16 to < 65 years old.

Retroperitoneoscopic adrenalectomy in semilateral supine position

Objective To discuss semilateral supine position for retroperitoneoscopic adrenalectomy. Methods From Jan. 2006 to Dec. 2008,36 patients ( 20 males and 16 females with mean age of 43 years) underwent retroperito-neoscopic adrenalectomy in 60° - 70°semilateral

Atypical cervical spondylotic radiculopathy resulting in a hypertensive emergency during cervical extension: A case report and review of literature

BACKGROUND Extensive research revealed the absence of reports documenting hypertensive emergencies precipitated by changes in the cervical spine posture.CASE SUMMARY We here present a 57-year-old woman diagnosed as having cervical spondylotic radiculopathy(CSR)who was scheduled for anterior cervical decompression and fusion.During post-anesthetic positioning,a sudden hypertensive surge was observed when the patient was in a supine position with the neck being slightly extended.This surge was promptly reversed through cervical flexion and head elevation.This event however required an alternate surgical approach for recovery—posterior laminoplasty and endoscopy-assisted nucleus pulposus removal.Following the 6-month outpatient follow-up period,cervical flexion and extension activities substantially improved in the patient without any episodes of increase in acute blood pressure.CONCLUSION Maintaining a safe hypotensive posture and performing rapid,thorough deco-mpression surgery may serve as effective interventions for patients presenting symptoms similar to those of CSR accompanied by hypertensive emergencies(HE).This would mitigate the underlying causes of these HEs.

Supine versus prone percutaneous nephrolithotomy for renal calculi:Our experience

Objectives:To compare operative times,safety,and effectiveness of percutaneous nephrolithotomy in the supine versus prone position.Materials and methods:An observational study of 100 patients was conducted in our institution for 2years from 2018 to 2020 divided into 2 groups:50 patients underwent modified supine percutaneous nephrolithotomy(PCNL)and 50 patients underwent standard prone PCNL.The inclusion criteria included a renal calculus(calyx or pelvis)of any size for which PCNL was indicated and exclusion criteria were patients having contraindications for PCNL such as bleeding disorders,pregnancy,high risk,and co-morbid conditions.The measured data included operative time,number of punctures,stone-free rate,length of hospital stays,and rate of complications.Results:The 2 groups were comparable in mean age,male to female ratio,calculus size,number of punctures,residual calculi,and postoperative fever and pain.The mean difference of hemoglobin in the supine PCNL group was 0.37 g/dL whereas in the prone PCNL group it was 0.61 g/dL.The p value was significant at 0.043.The mean time to finish from initial postion was 72.24 minutes in supine PCNL and 88.12 minutes in prone PCNL.The p value was significant(p<0.001).The mean time before puncture was 20.92 minutes in the supine position and 31.84 minutes in the prone position.The p value was significant(p<0.001).The mean time from puncture to finish was 51.32 minutes in the supine position and 56.28 minutes in the prone position.The p value was significant(p<0.001).Conclusions:As observed from this study,supine PCNL is associated with a significantly reduced operating time when compared to conventional prone position PCNL procedures.The postoperative complications such as pain and fever were not significantly different.Hence,the supine PCNL is an equally effective modality for treatment of a renal calculus with benefits of simultaneous retrograde access and less operative time compared to the prone PCNL.

Retrolaminar migration as a complication of intraocular silicone oil injection detected on unenhanced CT

AIM:To describe the clinical and radiologic features of retrolaminar migration silicone oil(SiO)and observe the dynamic position of ventricular oil accumulation in supine and prone.METHODS:For this retrospective study,29 patients who had a history of SiO injection treatment and underwent unenhanced head computed tomography(CT)were included from January 2019 to October 2022.The patients were divided into migration-positive and negative groups.Clinical history and CT features were compared using Whitney U and Fisher’s exact tests.The dynamic position of SiO was observed within the ventricular system in supine and prone.CT images were visually assessed for SiO migration along the retrolaminar involving pathways for vision(optic nerve,chiasm,and tract)and ventricular system.RESULTS:Intraocular SiO migration was found in 5 of the 29 patients(17.24%),with SiO at the optic nerve head(n=1),optic nerve(n=4),optic chiasm(n=1),optic tract(n=1),and within lateral ventricles(n=1).The time interval between SiO injection and CT examination of migration-positive cases was significantly higher than that of migration-negative patients(22.8±16.5mo vs 13.1±2.6mo,P<0.001).The hyperdense lesion located in the frontal horns of the right lateral ventricle migrated to the fourth ventricle when changing the position from supine to prone.CONCLUSION:Although SiO retrolaminar migration is unusual,the clinician and radiologist should be aware of migration routes.The supine combined with prone examination is the first-choice method to confirm the presence of SiO in the ventricular system.

Direct anterior total hip arthroplasty: Literature review of variations in surgical technique

The direct anterior approach to the hip has been suggested to have several advantages compared to previously popular approaches through its use of an intra-muscular and intra-nervous interval betweenthe tensor fasciae latae and sartorius muscles. Recent increased interest in tissue-sparing and minimallyinvasive arthroplasty has given rise to a sharp increase in the utilization of direct anterior total hip arthroplasty. A number of variations of the procedure have been described and several authors have published their experiences and feedback to successfully accomplishing this procedure. Additionally, improved understanding of relevant soft tissue constraints and anatomic variants has provided improved margin of safety for patients. The procedure may be performed using speciallydesigned instruments and a fracture table, however many authors have also described equally efficacious performance using a regular table and standard arthroplasty tools. The capacity to utilize fluoroscopy intraoperatively for component positioning is a valuable asset to the approach and can be of particular benefit for surgeons gaining familiarity. Proper management of patient and limb positioning are vital to reducing risk of intra-operative complications. An understanding of its limitations and challenges are also critical to safe employment. This review summarizes the key features of the direct anterior approach for total hip arthroplasty as an aid to improving the understanding of this important and effective method for modern hip replacement surgeons.

Acute compartment syndrome of the thigh following hip replacement by anterior approach in a patient using oral anticoagulants

Acute compartment syndrome(ACS) of the thigh following primary total hip arthroplasty(THA) is a highly uncommon complication and has not yet been reported before with regards to the anterior approach through the anterior supine interval. We present a case of a 69-year-old male patient with a history of stroke, who developed ACS of the thigh after elective THA while using therapeutic low molecular weight heparin as bridging for regular oral anticoagulation. ACS pathogenesis, diagnostic tools, treatment and relevant literature are discussed. The patient's ACS was recognized in time and treated by operative decompression with fasciotomy of the anterior compartment. Follow-up did not show any neurological deficit or soft-tissue damage.

Kappa angles in different positions in patients with myopia during LASIK

AIM： To investigate the difference in kappa angle between sitting and supine positions during laser-assisted in situ keratomileusis（LASIK）.·METHODS： A retrospective study was performed on395 eyes from 215 patients with myopia that received LASIK. Low, moderate, and high myopia groups were assigned according to diopters. The horizontal and vertical components of kappa angle in sitting position were measured before the operation, and in supine position during the operation. The data from the two positions were compared and the relationship between kappa angle and diopters were analyzed.· RESULTS： Two hundred and twenty-three eyes（56.5%） in sitting position and 343 eyes（86.8%） in supine position had positive kappa angles. There were no significant differences in horizontal and vertical components of kappa angle in the sitting position or horizontal components of kappa angle in the supine position between the three groups（P 〉0.05）. A significant difference in the vertical components of kappa angle in the supine position was seen in the three groups（P 〈0.01）. Differences in both horizontal and vertical components of kappa angles were significant between the sitting and supine positions. Positive correlations in both horizontal and vertical components of kappa angles（P 〈0.05） were found and vertical components of kappa angle in sitting and supine positions were negatively correlated with the degree of myopia（sitting position： r =-0.109; supine position： r =-0.172; P 〈0.05）.·CONCLUSION： There is a correlation in horizontal and vertical components of kappa angle in sitting and supine positions. Positive correlations in both horizontal and vertical components of kappa angle in sitting and supine positions till the end of the results. This result still needs further observation. Clinicians should take into account different postures when excimer laser surgery needs to be performed.

Comparing posture induced intraocular pressure variations in normal subjects and glaucoma patients

AIM:To compare the posture-induced variations in intraocular pressure(IOP)between the primary open angle glaucoma(POAG)and non-glaucomatous eyes.METHODS:A case-controlled age matched study was conducted in 55 successive newly diagnosed POAG and 56 non-glaucomatous patients seen in glaucoma clinic and general outpatient eye clinic in the Alex Ekwueme University Teaching Hospital,Abakaliki.The IOPs of eligible correspondents were measured with Perkin’s hand-held tonometer in the sitting,supine flat and supine with pillow positions respectively.Measurement of IOP in each position was done after 15 min of assuming such posture.RESULTS:The IOP difference between the sitting and supine flat position was significantly higher in the POAG than non-glaucoma subjects(7.68±2.08 vs 4.03±0.13 mm Hg,P<0.001).The IOP difference between the sitting and supine with pillow positions was 2.61±1.49 mm Hg for POAG and 1.44±0.70 mm Hg in non-glaucoma(P<0.001),while difference between supine flat and supine with pillow positions was 5.07±2.24 mm Hg in POAG and 2.59±0.66 mm Hg in non-glaucomatous patients(P<0.001).CONCLUSION:Greater variations in posture induced IOP occurred in POAG patients than non-glaucomatous.The posture induced IOP variation is lowest in the sitting position and highest in the supine flat position.Evaluation of posture induced IOP changes may be an important tool in the management of glaucoma.

Clinical evaluation of prone position ventilation in the treatment of acute respiratory distress syndrome induced by sepsis

BACKGROUND Acute respiratory distress syndrome(ARDS)is an acute,diffuse,inflammatory lung injury.Previous studies have shown prone position ventilation(PPV)to be associated with improvement in oxygenation.However,its role in patients with ARDS caused by sepsis remains unknown.AIM To analyze the clinical effects of PPV in patients with ARDS caused by sepsis.METHODS One hundred and two patients with ARDS were identified and divided into a control group(n=55)and a PPV treatment group(n=47).Outcomes included oxygenation index,lung compliance(Cst)and platform pressure(Pplat),which were compared between the two groups after ventilation.Other outcomes included heart rate(HR),mean arterial pressure(MAP),central venous pressure(CVP),left ventricular ejection fraction(LVEF),the length of mechanical ventilation time and intensive care unit(ICU)stay,and levels of C-reactive protein(CRP),procalcitonin(PCT),and interleukin-6(IL-6)after ventilation.Finally,mortality rate was also compared between the two groups.RESULTS On the first day after ventilation,the oxygenation index and Cst were higher and Pplat level was lower in the PPV group than in the conventional treatment group(P<0.05).There were no significant differences in oxygenation index,Cst,and Pplat levels between the two groups on the 2^(nd),4^(th),and 7^(th) day after ventilation(P>0.05).There were no significant differences in HR,MAP,CVP,LVEF,duration of mechanical ventilation and ICU stay,and the levels of CRP,PCT,and IL-6 between the two groups on the first day after ventilation(all P>0.05).The mortality rates on days 28 and 90 in the PPV and control groups were 12.77% and 29.09%,and 25.53% and 45.45%,respectively(P<0.05).CONCLUSION PPV may improve respiratory mechanics indices and may also have mortality benefit in patients with ARDS caused by sepsis.Finally,PPV was not shown to cause any adverse effects on hemodynamics and inflammation indices.

Neurogenic orthostatic hypotension with Parkinson's disease as a cause of syncope:A case report

BACKGROUND Syncope presents with diagnostic challenges and is associated with high healthcare costs.Neurogenic orthostatic hypotension(nOH)as one cause of syncope is not well established.We review a case of syncope caused by nOH in a patient with Parkinson's disease.CASE SUMMARY We describe a case of syncope caused by nOH in Parkinson's disease and review the literature.A 70-year-old man with Parkinson's disease had uncontrolled blood pressure for 1 mo,with blood pressure ranging from 70/40 to 220/112 mmHg,and once lost consciousness lasting for several minutes after getting up.Ambulatory blood pressure monitoring indicated nocturnal hypertension(up to 217/110 mmHg)and morning orthostatic hypotension(as low as 73/45 mmHg).Seated-to-standing blood pressure measurement showed that the blood pressure dropped from 173/96 mmHg to 95/68 mmHg after standing for 3 min from supine position.A diagnosis of nOH with supine hypertension was made.During the course of treatment,Midodrine could not improve the symptoms.Finally,the patient's blood pressure stabilized with simple strategies by strengthening exercises,reducing the duration of lying in bed in the daytime,and consuming water intake before getting up.CONCLUSION nOH is one of the causes of syncope.Ambulatory blood pressure monitoring is a cost-effective method for its diagnosis,and non-pharmacological measures are still the primary management methods.

Posterior interosseous nerve localization within the proximal forearm-a patient normalized parameter

AIM To provide a "patient-normalized" parameter in the proximal forearm. METHODS Sixty-three cadaveric upper extremities from thirty-five cadavers were studied. A muscle splitting approach was utilized to locate the posterior interosseous nerve(PIN) at the point where it emerges from beneath the supinator. The supinator was carefully incised to expose the midpoint length of the nerve as it passes into the forearm while preserving the associated fascial connections, thereby preserving the relationship of the nerve with the muscle. We measured the transepicondylar distance(TED), PIN distance in the forearm's neutral rotation position, pronation position, supination position, and the nerve width. Two individuals performed measurements using a digital caliper with inter-observer and intraobserver blinding. The results were analyzed with the Wilcoxon-Mann-Whitney test for paired samples. RESULTS In pronation, the PIN was within two confidence intervals of 1.0 TED in 95% of cases(range 0.7-1.3 TED); in neutral, within two confidence intervals of 0.84 TED in 95% of cases(range 0.5-1.1 TED); in supination,within two confidence intervals of 0.72 TED in 95% of cases(range 0.5-0.9 TED). The mean PIN distance from the lateral epicondyle was 100% of TED in a pronated forearm, 84% in neutral, and 72% in supination. Predictive accuracy was highest in supination; in all cases the majority of specimens(90.47%-95.23%) are within 2 cm of the forearm position-specific percentage of TED. When comparing right to left sides for TEDs with the signed Wilcoxon-Mann-Whitney test for paired samples as well as a significance test(with normal distribution), the P-value was 0.0357(significance-0.05) indicating a significant difference between the two sides.CONCLUSION This "patient normalized" parameter localizes the PIN crossing a line drawn between the lateral epicondyle and the radial styloid. Accurate PIN localization will aid in diagnosis, injections, and surgical approaches.