Casting in sport.

Attempts by sports medicine professionals to return high school athletes with hand and wrist injuries to competition quickly and safely have been the source of confusion and debate on many playing fields around the country. In addition to the differing views regarding the appropriateness of playing cast usage in high school football, a debate exists among sports medicine professionals as to which material is best suited for playing cast construction. Materials used in playing cast construction should be hard enough to provide sufficient stabilization to the injured area and include adequate padding to absorb blunt impact forces. The purpose of the biomechanical portion of this investigation was to attempt to determine the most appropriate materials for use in constructing playing casts for the hand and wrist by assessing different materials for: 1) hardness using a Shore durometer, and 2) ability to absorb impact using a force platform. Results revealed that RTV11 and Scotchcast were the "least hard" of the underlying casting materials and that Temper Stick foam greatly increased the ability of RTV11 to absorb impact. Assessment of the mechanical properties of playing cast materials and review of current developments in high school football rules are used to aid practitioners in choosing the most appropriate materials for playing cast construction.

Blood-tissue transport of exogenous albumin and immunoglobulin G in genetically analbuminemic rats.

Tracer uptake studies were carried out in adult female Nagase (NA) strain analbuminemic rats [derived from Sprague-Dawley (SD) stock] and in adult female SD controls to determine the extent to which capillary permeability to plasma proteins is altered in the absence of endogenous albumin. Accessory measurements (arterial pressure, central venous pressure, plasma and interstitial fluid protein concentrations and oncotic pressures, plasma volume, and interstitial fluid volume) confirm the report of Joles et al. [Am. J. Physiol. 257 (Renal Fluid Electrolyte Physiol. 26): F23-F28, 1989] that shows elevated plasma volumes, normal interstitial fluid volumes, nearly normal plasma oncotic pressures (due to elevated globulin concentrations), and lower interstitial fluid oncotic pressures. In skin, skeletal muscles, and heart muscle, clearances of exogenous heterologous (bovine) albumin were 20-40% higher in NA than in SD controls. In intestine, albumin clearances were 20-30% lower. In NA rats blood-to-tissue clearances of heterologous (bovine) immunoglobulin G in skin and heart were higher and in the intestine they were lower than in SD controls; however, clearances in skeletal muscles were not elevated. The differences between NA and SD are small compared with the large increases in macromolecular permeabilities reported by others for organs and single microvessels perfused with albumin-free fluids.(ABSTRACT TRUNCATED AT 250 WORDS)

Interstitial exclusion of albumin in rat tissues measured by a continuous infusion method.

Steady-state 125I-labeled rat serum albumin (125I-labeled RSA) concentration in plasma was maintained by intravenous infusion of tracer for 72-168 h with an implanted osmotic pump. At the end of the infusion period, the rat was anesthetized and nephrectomized, and extracellular fluid was equilibrated with intravenous 51Cr-labeled EDTA for 4 h. Five minutes before final plasma and tissue sampling, 131I-labeled bovine serum albumin (131I-labeled BSA) was injected intravenously as a plasma volume marker. Samples of skin, muscle, tendon, and intestine were assayed for all three tracers. Apparent distribution volumes were calculated as tissue tracer content/plasma tracer concentration. Interstitial fluid volume (Vi) was calculated as V51Cr-EDTA-V131I-BSA. Steady-state extravascular distribution of 125I-labeled RSA as plasma equivalent volume (Va,p) was calculated as V125I-RSA-V131I-BSA. Steady-state interstitial fluid concentrations of 125I-labeled RSA in skin, muscles, and tendon were measured with nylon wicks implanted postmortem, and steady-state interstitial albumin distribution volumes were recalculated as wick-fluid equivalent volumes (Va,w). Relative albumin exclusion fraction (Ve/Vi) was calculated as 1-Va,w/Vi. For skin and muscle, steady-state 125I-labeled RSA tissue concentrations were reached at 72 h. Ve/Vi for albumin averaged 26% in hindlimb muscle, 41% in hindlimb skin, 30% in back skin, 39% in tail skin, and 54% in tail tendon. For muscle, Ve/Vi corresponds to expectation if all tissue collagen and hyaluronan is dispersed in the interstitium. However, for skin and tendon, albumin exclusion is considerably lower than expected on this basis, suggesting that much of their collagen is organized into dense bundles of fibers containing no fluid accessible to 51Cr-labeled EDTA or 125I-labeled RSA.

Update on accelerated rehabilitation after anterior cruciate ligament reconstruction.

Rehabilitation of the anterior cruciate ligament (ACL) reconstructed knee continues to be a topic of intense interest among surgeons and therapists. Since 1987, over 880 patients who have undergone ACL reconstruction using the central one-third of the bone patellar tendon bone graft have followed our accelerated rehabilitation protocol. Follow-up of the patients reveals early return to athletic activity and maintenance of long-term stability. Our 1987 accelerated rehabilitation program continues to be modified, with less constraints placed on the postoperative patient in our present rehabilitation protocol. These recent changes are once again prompted by noncompliant patients who, with close follow-up evaluation, continue to yield excellent results. Our present accelerated rehabilitation protocol is divided into four phases. The initial phase encompasses the preoperative period. The second phase involves the initial 2 weeks post ACL reconstruction. The third phase dates from 2-5 weeks postoperation, and the final phase (greater than 5 weeks) involves a safe return to athletic play. Our goal with the accelerated rehabilitation protocol remains to decrease postoperative complications without jeopardizing the long term stability of the ACL reconstructed knee. J Orthop Sports Phys Ther 1992;15(6):303-308.

Traditional versus Accelerated Rehabilitation following ACL Reconstruction: A One-Year Follow-Up.

Postoperative rehabilitation programs are believed to influence clinical outcome. The purpose of this paper was to outline the evolution of postoperative rehabilitation following anterior cruciate ligament reconstruction. Because of the controversy surrounding accelerated ACL rehabilitation and the concept of gaining terminal knee extension immediately following reconstruction, the authors felt justified in carrying out a retrospective comparison of traditional rehabilitation versus an accelerated approach. The objective variables under consideration included range of motion, isokinetic strength, and ligamentous stability. Results showed that active and passive range of motion, including hyperextension, returned more quickly and more fully in the accelerated group. Ligamentous stability was found to be equal to or better in the accelerated group despite a more aggressive rehabilitation approach. The results of this study indicated that an accelerated rehabilitation program following ACL reconstruction resulted in improved range of motion and strength gains without compromising stability. J Orthop Sports Phys Ther 1992;15(6):309-316.

Arthrofibrosis in acute anterior cruciate ligament reconstruction. The effect of timing of reconstruction and rehabilitation.

Arthrofibrosis is a potential complication of acute ACL reconstruction. Arthrofibrosis prevents the patient from regaining full range of motion, particularly the terminal 5 degrees of full extension, postoperatively. We did a retrospective study of 169 acute ACL reconstructions in a population of young athletes (average age, 22 years). We sought to determine the optimal time to perform acute ACL reconstruction with respect to arthrofibrosis and the effects of an accelerated versus conventional rehabilitation program. The short-term results were evaluated by range of motion measurements and 13 week Cybex scores. Patients whose ligaments were reconstructed within the 1st week after injury (Group I) had a statistically significant (P less than 0.05) increased incidence of arthrofibrosis (limited extension, scar tissue) over patients who had ACL reconstruction delayed 21 days or more (Group III). At 13 weeks after the reconstruction procedure, Group III patients scored an average of 70% (compared to 51% for Group I, P less than 0.05) on the Cybex evaluation. They also showed a trend toward more flexion of the knee as well as near full extension. Patients who had an ACL reconstruction between 8 and 21 days after injury (Group II) had a similar incidence of arthrofibrosis as Group I when they followed a conventional rehabilitation program postoperatively. However, only a small number of cases (approximately 4%) of Group II patients who followed an accelerated postoperative rehabilitation program had any arthrofibrosis--an observation we also made in the Group III patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Sampling interstitial fluid from rat skeletal muscles by intermuscular wicks.

A modification of the implanted wick method (K. Aukland and H. O. Fadnes. Acta Physiol. Scand. 88: 350-358, 1973) was devised to sample interstitial fluid from rat muscles. Dry nylon wicks were inserted postmortem into intermuscular spaces between leg muscles by means of a plastic catheter, which was subsequently withdrawn. Inserting the wicks postmortem avoids contaminating wick fluid with proteins extravasated as a result of local inflammatory reactions; placing them intermuscularly avoids contamination by fluid and proteins from damaged muscle cells. Wick fluid protein concentrations (mg/ml) averaged 24.1 +/- 1.1 and 28.5 +/- 1.5 (means +/- SE) in medial and lateral hindlimbs muscles, respectively. The corresponding albumin concentrations were 13.0 +/- 0.7 and 13.9 +/- 0.7 mg/ml. Total protein and albumin concentrations in plasma were 54.1 +/- 0.8 and 22.5 +/- 0.3 mg/ml. Electrophoresis of wick fluid showed a pattern of peaks similar to that of plasma, with albumin relatively high and larger molecules relatively low. Proteins from muscle cells were not detected. Isotope studies (125I-labeled albumin, 51Cr-EDTA) showed that less than 2% of the albumin in wick fluid came directly from plasma and that wick fluid was not concentrated by cell swelling postmortem. Wick fluid from intermuscular wicks implanted in anesthetized rats in vivo had nearly the same total protein concentration as fluid from postmortem wicks, but albumin-to-globulin (A/G) ratios were slightly lower (1.22 +/- 0.07 vs. 1.53 +/- 0.21 measured by gel electrophoresis), and more significantly, nearly 50% of the albumin leaked to wick fluid from plasma as a result of wick implantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Butirosin, a new aminoglycosidic antibiotic complex: antibacterial activity in vitro and in mice.

Butirosin is a new aminoglycosidic antibiotic complex which has broad gram-negative and gram-positive inhibitory antibacterial activity, as well as some bactericidal properties. Significantly susceptible bacteria include strains of Staphylococcus aureus and Streptococcus pyogenes, and pathogenic gram-negative species such as Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and P. vulgaris, Salmonella enteritidis and S. typhimurium, Shigella flexneri and S. sonnei. Good activity by parenteral dosing was obtained in various acute mouse infections. Butirosin is especially interesting because of its activity against Pseudomonas aeruginosa in vitro, including gentamicin-resistant clinical isolates, and in experimental mouse infections at relatively low doses.

Disc-agar diffusion microbiological assay procedure for determining serum and urine levels of sulfacytine and other sulfonamides.

A reasonably precise, reproducible, and sensitive microbiological procedure for directly assaying sulfacytine and other sulfonamides as antibacterially active drugs has been developed by appropriately modifying the standard disc-agar diffusion technique. Blood and urine levels as low as 3 mug/ml may be determined through the use of a strain of Escherichia coli and a chemically defined agar medium devoid of sulfonamide antagonists. Results indicate that this assay method should be a useful adjunct to the Bratton-Marshall colorimetric procedure, by permitting the direct measurement of antibacterially active drug in clinical specimens.