The clinical doctorate: a framework for analysis in physical therapist education.

This article explores major considerations for analysis and discussion of the role of the clinical doctorate as the first professional degree in physical therapist education (DPT). A process for this analysis is posed based on a conceptual framework developed by Stark, Lowther, Hagerty, and Orczyk through grounded theory research on professional education. External influences from society and the profession, institutional and programmatic influences, and articulation of critical dimensions of professional competence and professional attitudes as major categories are discussed in relation to the DPT. A series of questions generated from the application of the model are put forth for continued discussion and deliberation concerning the DPT. We conclude that the DPT provides the best pathway to serve society, the patient, and the profession.

Relaxation electromechanical delay of the quadriceps during selected movement velocities.

The purpose of this study was to quantify the time between the cessation of EMG activity and cessation of torque production, or relaxation electromechanical delay, (R-EMD) of the quadriceps at three angular movement velocities. A Biodex dynamometer passively moved the right knee of 25 males through a given range at three velocities (10, 60 and 120 degrees per second). Subjects were instructed to actively extend their knees to a visual target, then to immediately relax. Biodex torque and position data, as well as surface EMG from the right Vastus Medialis (VM), Rectus Femoris (RF) and Vastus Lateralis (VL) were sampled simultaneously. EMG cessation was determined when activity fell below a threshold based on the muscle's resting EMG. Torque cessation was determined when the slope of the relaxation curve decreased to 10% of the initial value. R-EMD time for each quadriceps head at each velocity was determined by calculating the difference between these two times. To examine reliability, subjects were retested four days later. Approximately two thirds of the subjects were unable to consistently perform the motor task of abrupt relaxation at some or all of the tested velocities. This variability was ascribed to motor control issues. Average R-EMD times for all subjects, muscle segments and velocities ranged from 249 +/- 68 ms to 276 +/- 51 ms during the first test session, and 239 +/- 46 ms to 300 +/- 59 ms during the second session. These data are important in identification of physiologically meaningful cessation of muscle contraction, and may be beneficial in research studies focusing on the areas of motor control and motor learning, computerized movement analysis, and prediction models for the determination of muscular force from the EMG signal.

Patellofemoral alignment: reliability.

Clinical assessment of the patellofemoral alignment is frequently performed, yet the repeatability of these measurements has not been previously investigated. This study examined the reliability of measuring patellofemoral alignment. The Q angle, A angle, and patellar orientation (mediolateral tilt, mediolateral position, superoinferior tilt, and rotation) of 27 healthy subjects were measured over three trials using standardized positioning and operationally defined goniometric, pluri-cal caliper, and visual estimation measurement techniques. Intratester and intertester intraclass correlation coefficients of measurements obtained with the pluri-cal caliper and goniometer ranged from .52 to .86 and .003 to .61, respectively. Intratester and intertester standard errors of the instrumented measurements ranged from 1.6 to 3.5 degrees and 3.2 to 6.8 degrees (.28 and .55 cm for mediolateral position), respectively. Intratester kappa's of visually estimating patellar orientation ranged from .40 to .57. Intertester kappa's were between .03 and .30. The results suggest that both clinical estimation and instrumented measurement of patellofemoral alignment may be unreliable.

Electromyographic activity of selected trunk and hip muscles during a squat lift. Effect of varying the lumbar posture.

Electromyographic (EMG) activity of selected hip and trunk muscles was recorded during a squat lift, and the effects of two different lumbar spine postures were examined. Seven muscles were analyzed: rectus abdominis (RA), abdominal obliques (AO), erector spinae (ES), latissimus dorsi (LD), gluteus maximus (GM), biceps femoris (BF), and semitendinosus (ST). The muscles were chosen for their attachments to the thoracolumbar fascia and their potential to act on the trunk, pelvis, and hips. Seventeen healthy male subjects participated in the study. Each subject did three squat lifts with a 157-N crate, with the spine in both a lordotic and kyphotic posture. The lift was divided into four equal periods. EMG activity of each muscle was quantified for each period and normalized to the peak amplitude of a maximal voluntary isometric contraction (MVIC). A two-way analysis of variance (ANOVA) for repeated measures was used to analyze the effects of posture on the amplitude and timing of EMG activity during the lift. Two patterns of EMG activity were seen: a trunk muscle pattern (RA, AO, ES, and LD) and a hip extensor pattern (GM, BF, ST). In the trunk muscle pattern (TP), EMG activity was greatest in the first quarter and decreased as the lift progressed. In the hip extensor pattern (HP), EMG activity was least in the first quarter, increased in the second and third quarters, and decreased in the final phase of the lift. Differences (P < .05) were seen among subjects and in the timing of the muscle activity in all muscles.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of manual therapy on connective tissue.

The purpose of this manuscript is to examine the known and theoretical mechanical effects of therapeutic manual techniques on the connective tissue (CT) of joints and fasciae. Typical CT structures that could be influenced by manual techniques will be discussed. The behavior of CT under loading and the influence of immobilization on CT will be examined. The forces developed during manual techniques will be described, and their potential effects on the physical properties of CT will be discussed. Research priorities regarding the effects of manual therapy on CT will be outlined.

Kinematics, ground reaction force, and muscle balance produced by backward running.

This study was conducted at the University of Kentucky Biodynamics Laboratory in Lexington, KY and was partially supported by a grant from the Kentucky Chapter of the American Physical Therapy Association. Backward running (BR) is employed for conditioning and for rehabilitation in sports, orthopaedics, and neurology. Our purposes were to compare kinematics and training effects of BR to forward running (FR). Ten runners (6 males, 4 females, ages 20-34 years) were assigned to a backward running (BRG) or control (FRG) group. Subject isokinetic muscular torque production (IMTP) and biomechanics during FR and BR at 3.58 m/sec were studied at the beginning and after 8 weeks of training. Stance time was significantly shorter during BR. The peak vertical component of the ground reaction force (Fz) and Fz impulse were significantly less during BR. After training, knee extensor IMTP of the BRG increased significantly at 75 and 120 degrees /sec. We concluded that BR produced lower Fz stress than FR and improved knee extensor torque at low speeds. Backward running may be clinically useful for reducing stress to injured joints and for increasing knee extensor strength. J Orthop Sports Phys Ther 1989;11(2):56-63.

Comparison of selected pulse frequencies from two different electrical stimulators on blood flow in healthy subjects.

The purpose of this study was to measure the effects of selected frequencies from two different pulsed electrical stimulators on blood flow, blood pressure, and heart rate. Each of 30 healthy subjects attended 10 study sessions: 1 torque-testing session, 1 control session consisting of no electrical stimulation (ES), and 8 sessions of ES. All subjects received ES at an intensity sufficient to produce torque equal to 15% of the predetermined maximal voluntary contraction of their right quadriceps femoris muscle. The results of a multivariate analysis of variance showed that changes in blood flow during and after ES were dependent on pulse frequency but independent of stimulator type. Further analysis showed significant increases in blood flow with ES using 10, 20, and 50 pulses per second compared with 1 pulse per second. Inconsistent changes in blood pressure and heart rate were produced by ES. Based on the results of this study, effective clinical use of ES for promoting arterial blood flow to muscle would involve pulsed frequencies of 10 to 50 pulses per second.

Unilateral hindpaw amputation causes bilateral articular cartilage remodeling of the rat hip joint.

The purpose of this paper was to describe the remodeling of adult coxofemoral articular cartilage (AC) in response to altered weight bearing. Twelve adult male Sprague-Dawley rats underwent unilateral hindpaw transection at the distal tibiofibular junction (AmpCont group); another group of eight rats served as normal controls (Norm group). Subpopulations of both groups were injected with 35SO4 24 hr before harvest. All femora were harvested after 8 weeks. Safranin O stained longitudinal sections were used to determine AC thickness, cellularity, and proteoglycan (PG) staining. Regional grain counting was performed on autoradiographs. Analysis of the data revealed that the AC of Norm hips in the region near the fovea capitis femoris was significantly thicker, had a lower cell density, a greater PG density, and a lower 35SO4 incorporation rate per chondrocyte than the AC of the Norm lateral edge region. The intact limbs of the AmpCont animals demonstrated a relative thinning of the AC near the fovea capitis femoris, compared with the edge region, and reduced 35SO4 incorporation rate in the lateral edge region, compared with normal values. The operated limb of the AmpCont animals displayed a relative increase of PG density in the edge region compared with the foveal region and a reduced 35SO4 incorporation rate in the lateral edge region, compared with normal values. We concluded that rat coxofemoral AC responds bilaterally to unilateral hindpaw amputation through appropriate morphologic remodeling.

Effects of high voltage pulsed electrical stimulation on blood flow.

The purpose of this study was to determine whether high voltage electrical stimulation would increase blood flow to skeletal muscle in healthy subjects. Subjects were assigned to one of three groups: 1) an Electrical Stimulation (ES) Group (n = 16), 2) an Exercise (EX) Group (n = 14), or 3) a Control Group (n = 8). Isometric contractions were induced electrically at 30 Hz in the ES Group and performed volitionally in the EX Group for five minutes at intensities of 10% and 30% of predetermined maximal voluntary isometric contraction (MVC) efforts. Blood flow, heart rate, and blood pressure were unaffected in the ES Group, but blood flow and systolic blood pressure increased and decreased, respectively, for the EX Group at 30% of MVC. High voltage stimulation at a pulse rate of 30 Hz and at intensities needed to evoke contractions at 10% and 30% of MVC for plantar flexion did not increase blood flow at the popliteal artery.

Augmenting voluntary torque of healthy muscle by optimization of electrical stimulation.

The purpose of this study was to evaluate the ability of electrical stimulation (2,500-Hz sine waves, interrupted for 50 pulsed bursts per second) to improve muscle torque using low-dosage training characteristics. Fifteen healthy subjects (9 men, 6 women), 20 to 32 years of age, participated in the experiment. All subjects received electrical stimulation of the right anterior thigh musculature while their left leg served as the control. Electrical stimulation was repeated eight times per session, each stimulation producing isometric torque equal to 50% of the subject's maximum voluntary isometric contraction. The sessions were repeated twice a week over a period of five weeks. Results showed that electrical stimulation, when used with the specified low-dosage training characteristics of this study, will augment quadriceps femoris muscle torque of men.

Osteoarthritis. Effects on synovial joint tissues.

The purposes of this article are 1) to provide an updated summary of some aspects of research into osteoarthritis and 2) to stimulate physical therapy inquiry on its causes, effects, and treatments. The current literature concerning the pathological changes associated with osteoarthritis is reviewed in the context of specific joint tissues (ie, articular cartilage, bone, synovial membrane, capsule and capsular ligaments, muscle, and nerve). Correlations are drawn between the pathological effects of osteoarthritis on these tissues and commonly observed clinical changes. Gaps in the current research literature are discussed, and areas needing further research are highlighted.

Circulatory response of digital arteries associated with electrical stimulation of calf muscle in healthy subjects.

The purpose of this study was to investigate the effects of electrical stimulation (2,500-Hz sine wave modulated at 50 bursts per second) of the posterior calf musculature on the blood circulation of an unexercised part of the body, the ipsilateral digital arteries. Intensities of electrical stimulation sufficient to produce 15% and 30% of isometric maximum voluntary contraction (MVC) of the plantar flexor muscles were used. Twenty-four healthy subjects participated in this study and were assigned either to an Experimental Group receiving electrical stimulation (n = 13) or to a Control Group not receiving electrical stimulation (n = 11). Analysis of data revealed significant differences in finger blood flow when the calf musculature was stimulated electrically. We found significant differences in blood flow of the finger when torques produced by electrical stimulation of the calf musculature were raised to 15% and 30% of MVC. The results of the study indicate that blood flow in the ipsilateral finger decreases significantly when the posterior calf musculature is exercised artificially with electrical stimulation bursts.

Effect of graded electrical stimulation on blood flow to healthy muscle.

The purpose of this study was to determine whether 2,500-Hz sine-wave electrical stimulation modulated at 50 bursts per second producing graded muscular responses affects blood flow. Healthy volunteer subjects were assigned randomly to an Experimental group (n = 14) that received bursts of electrical stimulation to the gastrocnemius muscle or to a Control group (n = 14) that received no treatment. Using a Doppler device, pulsatility index (PI) values were determined for multivariate statistical analysis. Electrical stimulation graded to simulate isometric torques equivalent to 10% and then 30% of the subjects' isometric maximum voluntary contraction resulted in respective mean increases in PI values of 20.5% and 19.6% over prestimulation PI values. We found no significant difference in PI values between the two levels of torque. No significant change in PI values was found among the Control group subjects. Our results indicate that electrical stimulation, as used in this study, can alter the blood flow to the muscle being stimulated.