Page 99 - Athletic Health Handbook
P. 99
return to activity. However, the use of injections of hydrocortisone at the on tendon synthesis have shown a
these medications has been shown to tendo-achilles insertion.25 Since that decrease in the fibroblastic response,
result in deleterious effects to tissues time, multiple reports of ligamentous tendon weight, and load to failure
in various animal models; therefore, and tendinous rupture have been following their administration.18,34
care must be taken when utilizing described following injection of Given the reports of spontaneous
these medications in the athlete. corticosteroid agents.3,11,12,20,22 This tendon rupture and experimental data
clinical experience is corroborated by mentioned, many authors have
Basic Science laboratory studies, primarily in rat encouraged caution when utilizing
models, that have shown an inhibitory corticosteroid injection therapy.23,32,33
Effects on Tendon and effect of normal mesenchymal cell
Ligament Metabolism matrix production by corticosteroids.1 Effects on Articular Cartilage
Corticosteroids are capable of exerting Since connective tissue homeostasis is
their effects through regulation of dependent upon the breakdown and Multiple studies have revealed delete-
DNA/RNA as well as arachidonic turnover of collagenous tissues, loss rious effects of corticosteroids upon
acid metabolism. Phospholipase A2, of matrix production may ultimately normal articular cartilage. Mankin
the initial enzyme along the arachi- lead to tendon/ligament/fascia weak- and Conger26 demonstrated a
donic acid metabolic pathway, is ening and ultimate failure. profound dose-dependent, but
inhibited by corticosteroids; thus, reversible, decrease in chondrocyte
the production of arachidonic acid is Because of these issues, direct intra- protein and matrix production in
halted by these agents.29 As a result, tendinous and intra-ligamentous response to intra-articular hydrocor-
neither lipooxygenase nor cyclooxy- injection has long been discouraged. tisone in the rabbit model. A similar
genase have arachidonic acid available Both the mechanical effects of the study in rabbits revealed a dose-depen-
to produce the end-inflammatory injection as well as the biochemical dent decrease in the production of
mediators such as leukotrienes, effects of the corticosteroids have proteoglycans, proteins, and collagen4
prostaglandins, prostacyclins, and been shown to produce connective with the development of cystic
thromboxanes. Corticosteroids have tissue injury. Collagen necrosis with degeneration and fissuring in weight-
been shown to have multiple other significant tendon weakening has been bearing segments of the articular
effects beyond blocking production noted for up to two weeks following cartilage.4 These authors also found
of these molecules. Significant direct injection of betamethasone into that when the corticosteroid injec-
inhibitory effects have also been seen rabbit Achilles tendons.19 An addi- tions were discontinued the rates of
upon fibrous connective tissue forma- tional study in the rabbit model proteoglycan and collagen synthesis
tion. In 1957, H.B. Lee reported a showed collagen necrosis and fibrob- increased up to 900 percent; however,
rupture of the Achilles tendon in a last cell death following hydrocortisone it took six months for proteoglycan
33 year-old male cross-country runner injection into the tendoachilles.2 levels to return to normal.5 It must
after receiving multiple peri-tendinous Other experimental studies examining be noted that most animal studies
the deleterious effects of corticosteroids have involved the use of weekly

Table 1: Common Injectable Corticosteroid Formulations

Preparation Proprietary Concentration Average Duration
Name (mg/ml) of Action (Days)

Triamcinolone hexacetonide Aristospan 20 21
Triamcinolone diacetate Aristocort Forte 25–40 7
Triamcinolone acetonid 10–40 14
Methylprednisolone Na succinate Kenalog 40–125 4
Methylprednisolone acetate Solu-Medrol 40–80 8
Prednisolone tebutate Depo-Medrol 10–14
Betamethasone acetate Hydeltra-T.B.A. 20 9
Dexamethasone acetate 6 8
Dexamethasone Na phosphate Soluspan 8 6
Hydrocortisone acetate Decadron-LA 4 6
25
Decadron
Hydrocortone

*Adapted from Caldwell7

INJECTABLE CORTICOSTEROIDS 99
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