Are military fitness tests safe for members with a total hip arthroplasty?

INTRODUCTION

Canadian Armed Forces (CAF) members must complete an annual fitness evaluation. Members with a total hip arthroplasty (THA) may be at risk of injury during these strenuous tests. To inform CAF policy, we sought expert consensus on the safety of fitness testing for members with a THA.

METHODS

We conducted a three-round Delphi study with a panel of hip arthroplasty experts to determine the safety of CAF operational fitness evaluations for members with a THA. The experts evaluated videos of the 10 individual tasks included in the evaluations.

RESULTS

All individual tasks were judged to be safe by consensus. One task, which involves digging with a shovel, was considered safe provided that participants avoid deep hip flexion. The nine other tasks were judged to be safe without modifications or interventions. The experts also supported a policy recommendation that would allow members to perform military fitness evaluations if they (1) have a primary THA, (2) had no episodes of instability, (3) are at least 12 months postoperatively and (4) have been cleared by an orthopaedic surgeon and a physiatrist/physiotherapist.

CONCLUSION

A panel of arthroplasty experts concluded, based on video analysis, that CAF fitness evaluations are generally safe for members with a THA.

Activation of cAMP dependent protein kinase during surfactant release from type II pneumocytes

Release of surfactant from pulmonary type II epithelial cells was stimulated by the beta-adrenergic agonist terbutaline and the diterpene forskolin. Cytosolic cyclic adenosine monophosphate (cAMP) concentrations increased significantly following exposure to terbutaline or forskolin and reached maximal levels within 5 min after treatment. Terbutaline and forskolin had a synergistic effect on cytosolic cAMP levels when added simultaneously. cAMP-dependent protein kinase activity was identified in cytosolic preparations of type II pneumocytes by phosphorylation of the peptide substrate Kemptide (Leu-Arg-Arg-Ala-Ser-Leu-Gly) and binding of 3H-cAMP to the regulatory components of cAMP-dependent protein kinase. Type I and type II regulatory subunits of the cANP-dependent kinase were present in approximately equal concentrations in type II cell cytosol. Activation ratio of cAMP-dependent protein kinase in cultured type II cells increased significantly in the presence of terbutaline, forskolin, or terbutaline plus forskolin. Activation ratios increased from 0.45 +/- 0.03 for control cells to 0.96 +/- 0.06 for cells exposed to terbutaline (10 microM) plus forskolin (5 microM) for 20 min. Release of 3H-phosphatidylcholine was also stimulated by terbutaline and forskolin. Effects of terbutaline and forskolin on surfactant release were approximately additive. Our results demonstrated increased cytosolic cAMP levels, increased cAMP-dependent protein kinase activation ratios, and subsequent augmented surfactant release from isolated type II pneumocytes in response to terbutaline and forskolin. These data support a role for activation of cAMP-dependent protein kinase as a mediator of surfactant release and document the utility of forskolin for study of cAMP-mediated effects in isolated type II cells.