Peritendinous Corticosteroid Injections, Eccentric Decline Squat Training And Heavy Slow Resistance Training In Patellar Tendinopathy

Abstract

Patellar tendinopathy (PT) is a very frequent, persistent and disabling overload injury among jumping athletes. Tendinopathy is associated with tendon degeneration. No treatment of choice has been established for PT and comparative studies are scares. The underlying mechanisms of treatments in PT are highly unidentified. PURPOSE: Investigate the clinical, structural and tendon mechanical effects of three conservative treatments in PT. METHODS: 39 male PT patients were randomly allocated to 12 wks treatment consisting of either: 1) Peritendinous corticosteroid injections (CORT), 2) Eccentric decline unilateral squat training (ECC) or 3) Heavy slow resistance training (HSR). Subjects were examined at 0 wks, 12 wks and at half-year follow-up. Subjects indicated maximal tendon pain during activity on a VAS-scale and assessed symptoms and function in a VISA-p questionnaire. Subjects reported treatment satisfaction as "satisfied" or "not satisfied". Tendon swelling and vascularisation was assessed by ultrasound and Colour Doppler. Structural properties were assessed by MRI. Patellar tendon mechanical properties were assessed using simultaneous force and ultrasonography samplings. RESULTS: No differences existed between groups at 0 wks. All groups improved equally in VISA-p and VAS from 0 to 12 wks (p < 0.05). The VISA-p and VAS improvements were maintained at half-year follow-up in ECC and HSR but deteriorated in CORT (p<0.05). Tendon swelling decreased in CORT and HSR (13 + 2 & 12 + 2%, p < 0.05) but was unchanged in ECC. Vascularisation decreased in CORT and HSR (52 + 14 & 45 + 6%, p < 0.01) but was unchanged in ECC. Quadriceps cross sectional area increased in ECC and HSR (7 + 2 & 7 + 1%, p < 0.01) but was unchanged in CORT. At half-year follow up HSR were more satisfied than CORT and ECC. Patellar tendon mechanical properties did not differ in healthy and injured tendons and remained unchanged in all three groups. CONCLUSIONS: CORT had excellent short term, but poor long-term, clinical effects. HSR seems to have somewhat superior short and long-term effects. The mechanical properties of the patellar tendon are not affected by tendinopathy and do not change with either treatments.