Editorial
Chronic patellar tendinopathy is one of the two most common tendinopathies of the lower limb. It is a degenerative condition and not an inflammatory one. Diagnosis is based on defining pain features for example localized pain in the inferior pole of the patella which is the most common site of patellar tendinopathy as well as reproducing pain with specific clinical tests and palpation. Although the signs and symptoms of tendinopathy are relatively clear, to date, no ideal treatment has emerged. Many physiotherapy techniques have been recommended for the treatment/rehabilitation of patellar tendinopathy such as electrotherapeutic (ultrasound, ESWT, laser, iontophoresis) and non-electrotherapeutic modalities (exercise programs, soft tissue manipulation, and acupuncture). All the above-mentioned treatments intend to improve symptoms (pain and function) of patellar tendinopathy but have totally different mechanisms of action. However, a treatment is effective when it reverses the pathology of the tendinopathy and not only improve the symptoms.
Nowadays, eccentric training of the “injured” tendon is the most commonly used conservative approach in the treatment of tendinopathy [1]. However, Malliaras and his colleagues [2] performed a systematic review of studies comparing two or more loading programs in achilles and patellar tendinopathy. They concluded that clinicians should consider eccentric-concentric loading alongside or instead of eccentric loading. Recently, isometric exercises have been recommended to reduce and manage patellar tendon pain [3] and initiate muscle-tendon unit loading when pain limits the ability to perform isotonic exercises [4]. Otherwise, isometric evidence is currently limited to the patellar tendon. Furthermore, eccentric training of the injured tendon alone is not effective for many patients with tendinopathies [5]. Therefore, eccentric training of the injured tendon is combined with static stretching exercises of the injured tendon in the treatment of tendinopathies as it was first proposed by Stanish et al [6].
A component lacking from evidence-based programs is adequate consideration of the kinetic chain. Poor lumbopelvic control has the potential to alter load distribution on the lower limb kinetic chain and increase the risk of lower limb tendinopathy. It is our belief that the improvement of lumbo-pelvic control can be achieved by performing simple exercises such as single leg bridging in supine and four point prone bridging exercises [7,8]. Future research is needed to confirm this suggestion.
In addition, hip extensor weakness has been associated with patellar tendinopathy [9]. Exercises to strengthen these muscle groups should be considered in exercise protocols and patellar tendinopathy. Functional activities such as jumping, cutting and sprinting should also be included in lower limb tendinopathy rehabilitation programs among athletes, but have so far not been included in popular programs in the literature [9,10].
According to previous reported issues, it is time to stop strengthening the tendon only eccentrically. Isometric, concentriceccentric, stretching-eccentric and isolated eccentric loading may be indicated depending on factors multiple factors such as pain, function, age, site of tendinopathy, access to equipment, etc. The tendinopathy management should be based on a progressive loading of the lower extremity (kinetic chain), muscle-tendon unit, and tendon itself. However, the optimal protocol of exercise training needs to be investigated.
Patellar tendinopathy pain can also be reported, apart from the inferior pole of the patella, at the tibial tuberosity, at the superior pole of the patella and at the midportion of the tendon [10]. Future welldesigned studies are needed to find out the appropriate protocol of exercise training for each site of patellar tendinopathy.
References
- Alfredson H, Pietila T, Johnson P, Lorentzon R. Heavy load eccentric calf muscle training for the treatment of chronic achilles tendinosis. Am J Sports Med. 1998; 26: 360–366.
- Malliaras P, Barton C, Reeves N, Langberg H. Achilles and patellar tendinopathy loading programmes. a systematic review comparing clinical outcomes and identifying potential mechanisms for effectiveness. Sports Med. 2013; 43: 267–286.
- Ark M, cook J, Docking S et al. Exercise programs to decrease pain in athletes with patellar tendinopathy in season: a rct. Br J Sports Med. 2014; 48: a9– a10.
- Cook J, Purdam C. The challenge of managing tendinopathy in competing athletes. BJSm. 2014; 48: 1333.
- Cannell L, Taunton J, Clement D, et al. A randomized clinical trial of the efficacy of drop squats or leg extension/leg curls to treat clinically diagnosed jumper’s knee in athletes: a pilot study. Br J Sports Med. 2001;35: 60-64.
- Stanish WD, Rubinovich RM, Curwin S. Eccentric exercise in chronic tendinitis. clinOrthoprelat res. 1986; 208: 65–68.
- Dimitrios S. Achilles tendinopathy and lumbopelvic Stability. Rheumatology: Current Research. 2013; 4: 126.
- Kountouris A, Cook J. Rehabilitation of achilles and patellar tendinopathies. Best practice & research in clinical rheumatology. 2007 ; 21: 295-316.
- Silva RS, Ferreira AL, Nakagawath, Santos Je, Serrão FV. rehabilitation of patellar tendinopathy using hip extensors Strengthening and landing Strategy modification: case report With 6-months Follow-up. J Orthop Sports Physther. 2015; 45: 899-909.
- Malliaras P, Cook J, Purdam C, Rio E. Patellar tendinopathy: Clinical Diagnosis, load management and advice for challenging case presentations. J Orthop Sports Physther. 2015; 45: 887-898.