The convergence of regenerative medicine and rehabilitation: federal perspectives.

Regenerative rehabilitation is the synergistic integration of principles and approaches from the regenerative medicine and rehabilitation fields, with the goal of optimizing form and function as well as patient independence. Regenerative medicine approaches for repairing or replacing damaged tissue or whole organs vary from utilizing cells (e.g., stem cells), to biologics (e.g., growth factors), to approaches using biomaterials and scaffolds, to any combination of these. While regenerative medicine offers tremendous clinical promise, regenerative rehabilitation offers the opportunity to positively influence regenerative medicine by inclusion of principles from rehabilitation sciences. Regenerative medicine by itself may not be sufficient to ensure successful translation into improving the function of those in the most need. Conversely, with a better understanding of regenerative medicine principals, rehabilitation researchers can better tailor rehabilitation efforts to accommodate and maximize the potential of regenerative approaches. Regenerative rehabilitative strategies can include activity-mediated plasticity, exercise dosing, electrical stimulation, and nutritional enhancers. Critical barriers in translating regenerative medicine techniques into humans may be difficult to overcome if preclinical studies do not consider outcomes that typically fall in the rehabilitation research domain, such as function, range of motion, sensation, and pain. The authors believe that encouraging clinicians and researchers from multiple disciplines to work collaboratively and synergistically will maximize restoration of function and quality of life for disabled and/or injured patients, including U.S. Veterans and Military Service Members (MSMs). Federal Government agencies have been investing in research and clinical care efforts focused on regenerative medicine (NIH, NSF, VA, and DoD), rehabilitation sciences (VA, NIH, NSF, DoD) and, more recently, regenerative rehabilitation (NIH and VA). As science advances and technology matures, researchers need to consider the integrative approach of regenerative rehabilitation to maximize the outcome to fully restore the function of patients.

The influence of ankle joint movement on knee joint kinesthesia at various movement velocities.

The purpose of this study was to determine if gastrocnemius elongation or shortening and direction and velocity of knee movement influenced knee kinesthesia. Healthy volunteers sat with their knee flexed (20 degrees) and was then passively rotated (flexion or extension) at three velocities (0.5, 2, or 10 degrees/s) while the ankle was either fixed or rotated (dorsiflexed or plantar flexed at 0.17, 0.65, or 3.3 degrees/s) creating gastrocnemius elongation or shortening. Subjects activated a thumb switch, stopping motion once they detected onset and direction of the motion. Detection of passive movement sense (DPMS) was the angular movement before activation of a thumb-switch. Significant differences (P=0.003) in the rate of change in DPMS across a variety of movement velocities was observed but shortening or elongation of the gastrocnemius did not affect DPMS. Gastrocnemius elongation/shortening did not affect knee DPMS, simple reaction time plays an important role in testing kinesthesia especially at faster movements. While feedback from the gastrocnemius muscle plays a limited role in healthy subjects, differences in testing velocities may incorporate higher levels of central nervous system processing. Clinical measures of kinesthesia can be affected by both movement direction and movement velocity that are speed dependent.

Scapulothoracic latent muscle reaction timing comparison between trained overhead throwers and untrained control subjects.

AIM: This study evaluated select scapulothoracic muscles for training-induced latent muscle reaction timing (LMRT) changes. Comparisons were also made between the dominant and non-dominant upper extremities and between individual muscles. MATERIALS AND METHODS: Fifteen male trained overhead throwers (college baseball pitchers) and 15 male untrained, age-matched control subjects participated in this study. Scapulothoracic muscle activation data were collected as subjects attempted to stop a variably timed, sudden glenohumeral joint internal rotation perturbation. RESULTS: Training group differences were not evident for LMRT (P=0.56), however upper extremity dominance (P=0.003) and test muscle (P=0.0002) displayed significant differences. Dominant upper extremity upper trapezius muscle LMRT (72.5+/-26 ms) occurred later than non-dominant upper trapezius muscle LMRT (60.0+/-14.1 ms, P=0.001). Dominant upper extremity middle trapezius-rhomboid muscle LMRT (60.0+/-16.2 ms) occurred later than non-dominant middle trapezius-rhomboid muscle LMRT (50.2+/-12.6 ms, P=0.004). Dominant upper extremity upper trapezius muscle LMRT also occurred later than serratus anterior (55.7+/-16.0 ms, P=0.001) and middle trapezius-rhomboid LMRT (60.2+/-16 ms, P=0.003). Mean overall dominant upper extremity LMRT (62.7+/-19.4 ms) was delayed compared with mean overall non-dominant upper extremity LMRT (53.9+/-12.4 ms, P=0.003). CLINICAL CONSEQUENCES: Although training was not found to influence scapulothoracic LMRT, differences were observed between the dominant and non-dominant upper extremities. Consistent LMRT delays at the dominant upper extremity suggest possible neuromuscular timing differences to enable prolonged glenohumeral joint and scapulothoracic articulation acceleration before deceleration through eccentric muscle activation. Both trained and untrained overhead throwers displayed this response. Variable perturbation test velocities, and in-season testing of larger subject groups may be needed to better elucidate the more subtle differences associated with training.

Open reduction internal fixation after displacement of a previously nondisplaced acromial fracture in a multiply injured patient: case report and review of literature.

SUMMARY: A twenty-eight-year-old multiple trauma patient had a nondisplaced acromion fracture that was not detected until after it had displaced. Open reduction internal fixation was performed without complication and the patient achieved excellent shoulder abduction strength. Nondisplaced acromion fractures may displace if not protected. Open reduction internal fixation of displaced acromion fractures should be considered if deltoid muscle strength is important to the patient.

The meniscus: review of basic principles with application to surgery and rehabilitation.

OBJECTIVE: To review basic meniscal anatomy, histology, and biomechanical principles as they apply to surgery and rehabilitation. DATA SOURCES: We searched MEDLINE and CINAHL for the years 1960-1999 using the terms meniscus,surgery,rehabilitation,meniscal repair, and arthroscopy. DATA SYNTHESIS: Injuries to a healthy meniscus are usually produced by a compressive force coupled with transverse-plane tibiofemoral rotation as the knee moves from flexion to extension during rapid cutting or pivoting. The goal of meniscal surgery is to restore a functional meniscus to prevent the development of degenerative osteoarthritis in the involved knee. The goal of rehabilitation is to restore patient function based on individual needs, considering the type of surgical procedure, which meniscus was repaired, the presence of coexisting knee pathology (particularly ligamentous laxity or articular cartilage degeneration), the type of meniscal tear, the patient's age, preoperative knee status (including time between injury and surgery), decreased range of motion or strength, and the patient's athletic expectations and motivations. Progressive weight bearing and joint stress are necessary to enhance the functionality of the meniscal repair; however, excessive shear forces may be disruptive. Prolonged knee immobilization after surgery can result in the rapid development of muscular atrophy and greater delays in functional recovery. CONCLUSIONS/RECOMMENDATIONS: Accelerated joint mobility and weight-bearing components of rehabilitation protocols represent the confidence placed in innovative surgical fixation methods. After wound healing, an aquatic therapy environment may be ideal during all phases of rehabilitation after meniscal surgery (regardless of the exact procedure), providing the advantages of controlled weight bearing and mobility progressions. Well-designed, controlled, longitudinal outcome studies for patients who have undergone meniscectomy, meniscal repair, or meniscal reconstruction are lacking.

Shoulder proprioception: latent muscle reaction times.

PURPOSE: The purpose of this study was to identify electromyographic (EMG) differences in the latent muscle reaction timing (LMRT) of the rotator cuff between trained overhead throwers and control subjects in response to sudden internal rotation perturbation (P < or = 0.05). METHODS: Subjects included 15 trained overhead throwers (male intercollegiate baseball players) and 15 untrained subjects (males not active in competitive throwing sports). Subjects were tested while seated, with their dominant glenohumeral joint positioned in 90 degrees abduction/external rotation (scapular plane), their elbow flexed to 90 degrees, and their forearm placed in the perturbation device. Rotator cuff LMRT was assessed as they tried to decelerate a variably timed, sudden internal rotation force. EMG sampling (2000 Hz, 2-s duration) began immediately before perturbation. RESULTS: Trained throwers had slower infraspinatus (P = 0.011) and teres minor (P = 0.024) LMRT and decreased supraspinatus (P = 0.001) and posterior deltoid (P = 0.0001) muscle activation duration compared with control subjects. CONCLUSIONS: These results suggest that the rotator cuff muscles of trained throwers may be downregulated in response to sudden internal rotation perturbation. Although these adaptations would enable greater internal rotation velocities during overhead throwing, they may also contribute to glenohumeral joint pathology. The identification of changes in rotator cuff LMRT in response to sudden internal rotation perturbation suggests an area of acquired neuromuscular imbalance warranting consideration by those involved in the rehabilitation and conditioning of the overhead throwing athlete.

Adenoviral nerve growth factor and beta-galactosidase transfer to spinal cord: a behavioral and histological analysis.

OBJECT: The present study characterizes the time course and loci of gene expression induced by the administration of adenoviral vectors into spinal cord. Although a marked inflammatory response to these vectors occurred, no effect on spinal cord function was seen in the 1st postoperative week. The expression of transgenic genes delivered by viral vectors is being exploited throughout the nervous system. The present study utilized adenoviral vectors containing the Rous sarcoma virus (RSV) promoter and a nuclear localization signal to achieve transgenic expression in mammalian spinal cord. METHODS: Initial experiments utilizing the vector Ad.RSVlacZ (10(12) particles/ml) injected into the region of the central canal resulted in viral gene expression stretching over approximately 1.2 cm of spinal cord. Gene expression was first detected 3 days following viral administration and lasted until postinjection Day 14 with peak expression at Day 7. A variety of cell types in both white and gray matter expressed lacZ. Transgenic expression of the neurotrophin nerve growth factor (NGF) was achieved using injections of Ad.RSVNGF. On histological examination mononuclear inflammatory infiltrate and gliosis were revealed surrounding the injection sites of spinal cords receiving adenovirus but not vehicle. To assess spinal cord function during viral gene expression, animals previously trained in an operant runway task were tested at 7 days postinjection (the peak of viral gene expression) and demonstrated no changes in spinal cord function. CONCLUSIONS: Results of this study using adenoviral neurotrophic gene transfer indicate that it provided an effective tool for the delivery of potentially therapeutic proteins to the injured or diseased spinal cord.

Does pulsed low intensity ultrasound allow early return to normal activities when treating stress fractures? A review of one tarsal navicular and eight tibial stress fractures.

We sought to evaluate the efficacy of daily pulsed low intensity ultrasound (LIUS) with early return to activities for the treatment of lower extremity stress fractures. Eight patients (2 males, 6 females) with radiographic and bone scan confirmed tibial stress fractures participated in this study. Additionally, a case report of a tarsal navicular stress fracture is described. All patients except one were involved in athletics. Prior to the study, subjects completed a 5 question, 10 cm visual analog scale (VAS) regarding pain level (10 = extreme pain, 1 = no pain) and were assessed for functional performance. Subjects received 20-minute LIUS treatments 5 times a week for 4 weeks. Subjects maintained all functional activities during the treatment period. Seven patients with posterior-medial stress fractures participated without a brace. Subjects were re-tested after 4 weeks of treatment. Mann-Whitney U tests (VAS data) and paired t-tests (functional tests) assessed statistical significance (p<0.05). Although the intensity of practice was diminished in some instances, no time off from competitive sports was prescribed for the patients with the tibial stress fractures. The patient with the anterior tibial stress fracture underwent tibial intramedullary nailing at the conclusion of a season of play. In this uncontrolled experience, treatment of tibial stress fractures with daily pulsed LIUS was effective in pain relief and early return to vigorous activity without bracing for the patients with posterior-medial stress fractures.

Scapular avulsion fracture of a high school wrestler.

This case study details a rare injury managed conservatively with aggressive therapy with early return to competition. A 17-year-old high school wrestler suffered indirect trauma to the right upper extremity. The patient was forced to the mat where he felt pain in the posterior aspect of his shoulder and was point tender over the inferior pole of his right scapula. Radiographs reveal an avulsion fracture at the inferior angle of the scapula. Aggressive therapy included modalities to control inflammation and muscle guarding in addition to early scapular mobility. Maintenance of glenohumeral motion and upper extremity strengthening was started within a week. The patient was able to wrestle in the state tournament 3 weeks after initial injury. At the 6-month follow-up, the patient had no clinical tenderness, full range of motion, and no motor deficits. The outcome resulted in clinical and radiological healing of the fracture and no functional deficits.

A trial to investigate reactions and responses to BCG vaccines of different strengths prepared from the Copenhagen 1331 strain.

Seven hundred and ninety-three tuberculin-negative school-children were vaccinated with BCG vaccine prepared from either the 1077 substrain, at 0-3 mg/ml moist weight, or the 1331 substrain at 0-15 and 0-3 mg/ml moist weight. Local vaccination reactions and Mantoux tuberculin conversion were measured. There were no differences between the 1077 vaccine and the lower strength 1331 vaccine. The more potent 1331 product, however, produced marginally larger vaccination lesions and a slightly increased tuberculin allergy. The small increase in size of the vaccination lesions was considered acceptable and vaccine of this type would be satisfactory for use in the United Kingdom.