Pubofemoral distances correlate to acetabular morphology and sonological instability in screening for hip dysplasia.

Aims: The present study seeks to investigate the correlation of pubofemoral distances (PFD) to α angles, and hip displaceability status, defined as femoral head coverage (FHC) or FHC during manual provocation of the newborn hip < 50%. Methods: We retrospectively included all newborns referred for ultrasound screening at our institution based on primary risk factor, clinical, and PFD screening. α angles, PFD, FHC, and FHC at follow-up ultrasound for referred newborns were measured and compared using scatter plots, linear regression, paired t-test, and box-plots. Results: We included 2,735 newborns, of whom 754 received a follow-up hip ultrasound within six weeks of age. After exclusion, 1,500 hips were included for analysis. Sex distribution was 372 male and 380 female, and the mean age at examination was 36.6 days (4 to 87). We found a negative linear correlation of PFD to α angles (p < 0.001), FHC (p < 0.001), and FHC during provocation (p < 0.001) with a 1 mm increase in PFD corresponding to a -2.1° (95% confidence interval (CI) -2.3 to -1.9) change in α angle and a -3.4% (95% CI -3.7 to -3.0) change in FHC and a -6.0% (-6.6 to -5.5) change in FHC during provocation. The PFD was significantly higher with increasing Graf types and in displaceable hips (p < 0.001). Conclusion: PFD is strongly correlated to both α angles and hip displaceability, as measured by FHC and FHC during provocation, in ultrasound of newborn hips. The PFD increases as the hips become more dysplastic and/or displaceable.

Birthweight correlates to pubo-femoral distances and α angles in hip ultrasound of newborns at 6 weeks of age: a retrospective cohort study.

BACKGROUND AND PURPOSE: There is inconsistency in the literature regarding the relationship between increased birthweight and risk of developmental dysplasia of the hip (DDH). We aimed to investigate the correlation between birthweight and pubo-femoral distance (PFD), as well as Graf's α angle in newborns undergoing hip ultrasound examination at 6 weeks of age. PATIENTS AND METHODS: Basic newborn characteristics and ultrasound measurements were retrospectively collected during a 1-year study period. We excluded multiple births, newborns born at less than 37 gestational weeks, and incomplete information. Simple and multiple linear regression analyses were performed to evaluate the correlation of birthweight and PFD, and, second, birthweight and α angles including a stratified regression analysis investigating the potential effect modification of sex. RESULTS: 707 newborns (1,414 hips) were included. Mean birthweight was significantly higher for male newborns (P < 0.001). Increased birthweight was positively correlated to PFD values (crude coefficient 0.21, 95% confidence interval [CI] 0.10-0.32) and the correlation was still present after adjusting for sex, family history, and breech presentation (adjusted coefficient 0.18, CI 0.07-0.29). The stratified α angle model for the males was significant for both the crude coefficient (-0.73, CI -1.28 to -0.19) and the adjusted (-0.59, CI -1.15 to -0.03), and also for the females (crude coefficient -1.14, CI -1.98 to -0.31 and adjusted coefficient -1.15, CI -1.99 to -0.31). CONCLUSION: We found that increased birthweight positively correlated to PFD, and negatively correlated to α angle, but this was not of clinical significance.

Pubo-Femoral Distances Measured Reliably by Midwives in Hip Dysplasia Ultrasound.

The pubo-femoral distance (PFD) has been suggested as an ultrasound screening tool for developmental dysplasia of the hip (DDH). The aim of this study was to examine if midwives undergoing minimal training could reliably perform pediatric hip ultrasound and PFD measurements. Eight recruited midwives performed two rounds of independent blinded PFD measurements on 15 static ultrasound images and participated in four supervised live-scanning sessions. The midwives were compared to a group of three experienced musculoskeletal radiologists. Reliability was evaluated using inter-rater correlation coefficients (ICC). Linear regression was used to quantify the learning curve of the midwives as a group. There was near complete intra- and inter-rater agreement (ICC > 0.89) on static ultrasound images across both rounds of rating for midwives and radiologists. The midwives performed a mean of 29 live hip scans (range 24−35). The mean difference between midwives and supervising radiologists was 0.36 mm, 95% CI (0.12−0.61) for the first session, which decreased to 0.20 mm, 95% CI (0.04−0.37) in the fourth session. ICC for PFD measurements increased from 0.59 mm, 95% CI (0.37−0.75) to 0.78 mm, 95% CI (0.66−0.86) with progression in sessions. We conclude that midwives reliably perform PFD measurements of pediatric hips with minimal training.

Abnormal corticospinal excitability in patients with disorders of consciousness.

BACKGROUND: Transcranial magnetic stimulation (TMS) has been frequently used to explore changes in the human motor cortex in different conditions, while the extent of motor cortex reorganization in patients in vegetative state (VS) (now known as unresponsive wakefulness syndrome, UWS) and minimally conscious (MCS) states due to severe brain damage remains largely unknown. OBJECTIVE/HYPOTHESIS: It was hypothesized that cortical motor excitability would be decreased and would correlate to the level of consciousness in patients with disorders of consciousness. METHODS: Corticospinal excitability was assessed in 47 patients (24 VS/UWS and 23 MCS) and 14 healthy controls. The test parameters included maximal peak-to-peak M-wave (Mmax), F-wave persistence, peripheral and central motor conduction times, sensory (SEP) and motor evoked (MEP) potential latencies and amplitudes, resting motor threshold (RMT), stimulus/response curves, and short latency afferent inhibition (SAI). TMS measurements were correlated to the level of consciousness (assessed using the Coma Recovery Scale-Revised). RESULTS: On average, the patient group had lower Mmax, lower MEP and SEP amplitudes, higher RMTs, narrower stimulus/response curves, and reduced SAI compared to the healthy controls (P < 0.05). The SAI alterations were correlated to the level of consciousness (P < 0.05). CONCLUSIONS: The findings demonstrated the impairment of the cortical inhibitory circuits in patients with disorders of consciousness. Moreover, the significant relationship was found between cortical inhibition and clinical consciousness dysfunction.

Corticospinal excitability in patients with anoxic, traumatic, and non-traumatic diffuse brain injury.

BACKGROUND: Transcranial magnetic stimulation (TMS) have been frequently used to explore changes in motor cortex excitability in stroke and traumatic brain injury, while the extent of motor cortex reorganization in patients with diffuse non-traumatic brain injury remains largely unknown. OBJECTIVE/HYPOTHESIS: It was hypothesized that the motor cortex excitability would be decreased and would correlate to the severity of brain injury and level of functioning in patients with anoxic, traumatic, and non-traumatic diffuse brain injury. METHODS: TMS was applied to primary motor cortices of 19 patients with brain injury (5 traumatic and 14 non-traumatic causes; on average four months after insult), and 9 healthy controls. The test parameters included resting motor threshold (RMT), short intracortical inhibition (SICI), intracortical facilitation (ICF), and short latency afferent inhibition (SAI). Excitability parameters were correlated to the severity of brain injury measured with Glasgow Coma Scale and the level of functioning assessed using the Ranchos Los Amigos Levels of Cognitive Functioning Assessment Scale and Functional Independence Measure. RESULTS: The patient group revealed a significantly decreased SICI and SAI compared to healthy controls with the amount of SICI correlated significantly to the severity of brain injury. Other electrophysiological parameters did not differ between the groups and did not exhibit any significant relationship with clinical functional scores. CONCLUSIONS: The present study demonstrated the impairment of the cortical inhibitory circuits in patients with brain injury of traumatic and non-traumatic aetiology. Moreover, the significant correlation was found between the amount of SICI and the severity of brain injury.

Robotic gait training in patients with impaired consciousness due to severe traumatic brain injury.

PRIMARY OBJECTIVE: This prospective controlled non-randomized study investigated the effects of robotic gait training on electroencephalographic (EEG) brain activity in patients with impaired consciousness due to severe traumatic brain injury (TBI). METHODS: Twelve TBI patients and 14 healthy controls underwent a single training session on a computer-driven gait orthosis (Lokomat®). The sensory pathways were assessed using sensory evoked potentials (SEPs). The global delta-alpha EEG power ratio (DAR) and latency of the P300 component of the event-related potentials was assessed prior to and following a training session. RESULTS: Baseline measurements showed impaired SEPs in the majority of patients and significantly larger DAR in patients compared to healthy controls. Robotic gait training resulted in a reduction of the DAR in healthy subjects but not in patients. No changes were observed in P300 latencies after training in either patients or healthy controls. CONCLUSION: The study showed that robotic gait training induced measurable changes in the EEG power spectrum in healthy individuals, while no changes were observed in patients with severe TBI. The absence of the EEG changes following training might be an indicator of the severity of brain dysfunction.

Disorders of consciousness: further pathophysiological insights using motor cortex transcranial magnetic stimulation.

Transcranial magnetic stimulation (TMS) is a noninvasive means of investigating the function, plasticity, and excitability of the human brain. TMS induces a brief intracranial electrical current, which produces action potentials in excitable cells. Stimulation applied over the motor cortex can be used to measure overall excitability of the corticospinal system, somatotopic representation of muscles, and subsequent plastic changes following injury. The facilitation and inhibition characteristics of the cerebral cortex can also be compared using the modulatory effect of a conditioning stimulus preceding a test stimulus. So called paired-pulse protocols have been used in humans and animals to assess GABA (gamma-amino-butyric acid)-ergic function and may have a future role directing therapeutic interventions. Indeed, repetitive magnetic stimulation, where intracranial currents are induced by repetitive stimulation higher than 1 Hz, has been shown to modulate brain responses to sensory and cognitive stimulation. Here, we summarize information gathered using TMS with patients in coma, vegetative state, and minimally conscious state. Although in the early stages of investigation, there is preliminary evidence that TMS represents a promising tool by which to elucidate the pathophysiological sequelae of impaired consciousness and potentially direct future therapeutic interventions. We will discuss the methodology of work conducted to date, as well as debate the general limitations and pitfalls of TMS studies in patients with altered states of consciousness.