Shockwave therapy and ultrasound therapy for chronic patellar tendinopathy

The main aim of the study is to assess the efficacy of radial shock wave and ultrasound therapies for patellar tendinopathy . Patients diagnosed with patellar tendinopathy will be randomly allocated to one of three experimental groups: Group A: radial shock wave therapy Group B: ultrasound therapy Group C: placebo ultrasound Group A - radial shock waves will be applied without local anesthesia using ShockMaster 500 (Gymna-Uniphy) with a pneumatic applicator. A gel will be applied on the patient’s skin in the target area to help conduct the shock waves. Shockwave therapy will be applied at the patellar ligament extending from the apex of the patella to the tibial tuberosity. The patient will be positioned supine with a roll under the knees. Applicator: standard 15 mm applicator, D-Actor vibration applicator. Pressure: 2.5 bars Number of shocks: 3000 Frequency: 8 Hz. Number of therapy sessions: 3 (duration of intersession break 4-10 days). Duration of each session: approximately 5-7 minutes Group B - sonotherapy will be performed with a device for ultrasound applications – Pulson 400(Gymna). The skin will be coated with a coupling agent, ie., ultrasound gel. The patient will be positioned supine with a roll under the knees. Tranducer head size: 4 cm^2. Ultrasound frequency: 3 MHz. Ultrasound power density (spatial average of the density): 1 W/cm^2. Pulse ratio (duty cycle): 50 %. The duration of a therapy session will depend on the size of the treatment area – each square centimeter will be exposed to ultrasonic energy for 1 to 2.5 minutes. Frequency of therapy sessions: everyday, five days a week (except for Saturday and Sunday). Number of therapy sessions: 10. Duration of each session: approximately 7-10 minutes The parameters of the treatment in Group A and in Group B were determined based on our own clinical experience and reasoning, literature review (Val Robertson et al.: Electrotherapy Explained, Principles and Practice, 4th Edition, Elsevier; Król Piotr & Franek Andrzej: Fala uderzeniowa w leczeniu dysfunkcji ukladu narzadów ruchu, Meden 2014) and general principles of application of physical modalities. During the first two weeks of the therapy, all study groups will also undergo deep friction massage. The following measurements will be performed to objectively assess therapy effects: I. Stabilography will be carried out using 2 AMTI AccuSway platforms with integrated sensors to register ground reaction forces and the horizontal torque applied by the subject’s feet. A two-platform test (Platforms A and B) will consist of 7 trials: a/ Quiet standing with one foot resting on Platform A and the other on Platform B situated next to Platform A. Two 60-second trials in a quiet standing position will be recorded for each of the two testing conditions: eyes open and eyes closed. b/ Two lean-forward trials to the limits of stability (LOS) with movement at the ankles only. The protocol of LOS will consist of three phases: Phase 1 – 10s of quiet standing (quiet standing with one foot resting on Platform A and the other on Platform B situated next to Platform A); Phase 2 – the maximal forward-lean in a self-paced manner; Phase 3 – maintenance of the maximal forward-lean. c/ Two lean-backward trials to the limits of stability (LOS) with movement at the ankles only. The protocol of LOS will consist of three phases: Phase 1 – 10s of quiet standing (quiet standing with one foot resting on Platform A and the other on Platform B situated next to Platform A); Phase 2 – the maximal backward-lean in a self-paced manner; Phase 3 – maintenance of the maximal backward-lean. The step initiation's tests: d/ Three repetitions: quiet standing on platform A for 15 seconds, then changing to Platform B (1 step) followed by quiet standing for another 15 seconds. The distance between platforms: 10cm. e/ Three repetitions:quiet standing on Platform A for 15 seconds, then changing to Platform B (1 step) followed by quiet standing for another 15 seconds. A 15-cm obstacle over the edge of the platforms; the distance between platforms: 10 cm. f/ Three repetitions – quiet standing on Platform A for 15 seconds, then changing to Platform B (1 step up) followed by quiet standing for another 15 seconds. Platform B is placed on a 17-cm base directly at the edge of Platform A. g/ Three repetitions – quiet standing on Platform B for 15 seconds, then changing to Platform A (1 step down) followed by quiet standing for another 15 seconds. Platform B is placed on a 17-cm base directly at the edge of Platform A. Platform changing will each time start at a sound signal. The procedure of step initiation will be performed twice to make sure that each trial is initiated using alternate limbs. II. Vertical jump (without an arm swing) measurements will be taken on an AMTI AccuSway platform. The following trials will be performed: - countermovement jump (starting position: quiet standing) , - squat jump (starting position: knees flexed to 90°). In each of the above trials the patients will perform three maximal jumps and three sub-maximal jumps (approximately 50% of the maximum height). - muscle stiffness test: five maximal countermovement jumps in a row without an arm-swing, with a minimum bend at lower limb joints. The diagnosis of patellar tendinopathy will be made by an orthopedic surgeon. Shockwave and ultrasound therapy will be carried out by a physiotherapist. Posturography tests, vertical jump measurements and questionnaire survey will be conducted by another therapist. Posturographic measurements, countermovement jump quantification, forward body lean and subjective assessment will be taken prior to therapy and at 1, 6, and 24 weeks of therapy completion. There are no plans to assess fidelity or adherence, or strategies to promote adherence or fidelity.