Welke factoren zijn bepalend voor het resultaat van een conservatieve behandeling in geval van patellapeestendinopathie?
- FienJonnaert
Patellapeestendinopathie of ‘jumpers knee’ is een chronische sportblessure die hoge prevalentiecijfers heeft bij sporters betrokken in loop- en springsporten (1,2). Voornamelijk volleybal- en basketbalspelers worden hier frequent door getroffen. Patellapeestendinopathie ontstaat hoofdzakelijk op basis van mechanische overbelasting en heeft een weefseldegeneratief karakter (3,7,11). Hiernaast spelen tal van intrinsieke en extrinsieke risicofactoren (2,7,8,9,11) een rol in ontstaan en onderhoud van het peesletsel, dat zich in de meerderheid der gevallen voordoet ter hoogte van de proximale peesinsertie aan de inferieure patellapool (2,4,5). Door deze complexe, individueel sterk variabele etiopathogenese en het chronische karakter van peesproblemen (te wijten aan de zeer lage metabole activiteitsgraad van peesweefsel en een daaruit volgend vertraagde regeneratierespons), vormt de pathologie van jumpers knee een grote uitdaging voor menig (para)medicus (6). Ook bij de sporter zorgt patellapeestendinopathie, door aanzienlijke pijn , dysfunctie, verlies aan trainingsuren en competitie die ermee gepaard gaan, voor frustratie en ontevredenheid (1,7,12).
Snelle, accurate diagnostiek en adequate, causaal georiënteerde therapie zijn in deze gevallen dan ook essentieel. Kinesitherapie vormt tot op heden de 1e lijn behandeling bij deze sportspecifieke overbelastingblessures. Excentrische oefentherapie door middel van uni- en bipodale squats op een 25° gedeclineerd plankje vormen momenteel de gouden standaard binnen de medische trainingstherapie en het conservatief kinesitherapeutisch management (10,13,14,15). Ondanks de frequent aangetoonde therapeutische successen, vertoont een bepaald patiëntenpercentage relatieve of absolute resistentie aan dit primair conservatief beleid. Dergelijke patiënten zijn genoodzaakt meer invasieve medische behandelingen en zelfs chirurgische interventies te ondergaan, zonder zekerheid op definitief herstel (12,16).
Wat maakt dat sommige patiënten een goede therapierespons vertonen en anderen daarentegen (bijna) geen klinische en/of functionele vooruitgang boeken, is niet geweten. Binnen deze studie werd op zoek gegaan naar factoren die, naast een rol in ontstaan en onderhoud van patellapeestendinopathie, mogelijks ook verband houden met (de mate van) therapierespons. 14 patiënten (18 knieën) die gediagnosticeerd werden met patellapeestendinopathie werden geëvalueerd, op een aantal met letselrisico en –onderhoud geassocieerde parameters, voor en na een kinesitherapeutische (excentrische oefentherapie) behandelperiode van 6 weken.
De deelnemers werden getest op quadricepskracht, lenigheid van quadriceps en hamstrings (2,8,9), mate van intratendineuze patellapeesdoorbloeding (17,18), echografische peespresentatie (weefselkwaliteit), pijnintensiteit en functionaliteit (unipodale vertesprong en maximum aantal unipodale gedeclineerde squats). Veranderingen binnen de geteste parameters over de 6 weken durende trainingsperiode werden vervolgens vergeleken met klinische en functionele vooruitgang of achteruitgang.
Er kon worden geconcludeerd dat een positieve therapierespons, op basis van zowel klinische als functionele verbetering, in verband gebracht kan worden met een verbetering in quadricepskracht, quadricepsflexibiliteit en een toename in intratendineuze doorbloeding (bloodflow), geregistreerd ter hoogte van de proximale peesinsertie (i.e. de dominante letselregio). Deze factoren dienen dus goed onderzocht en adequaat geremedieerd te worden binnen conservatief management in geval van patellapeestendinopathie.
Dat voldoende lenigheid en kracht een voorwaarde zijn voor degelijk functioneel en klinisch herstel hoeft geen betoog, het feit dat deze verbetering ook effectief gepaard gaat met een significante toename in intratendineuze doorbloeding ter hoogte van de proximale peesinsertie (letsellocatie) werd met deze studie voor het eerst aangetoond. Gezien onvoldoende intratendineuze doorbloeding mede verantwoordelijk is voor het degeneratieve en chronische karakter van (patellapees)tendinopathieën en hier kon worden aangetoond dat excentrische oefentherapie effectief resulteert in een toegenomen bloodflow (en zodoende waarschijnlijk ook een toegenomen metabole activiteitsgraad), mag laatste dus beschouwd worden als zijnde een essentieel onderdeel van het oefentherapeutisch management binnen een kinesitherapeutische interventie.
Gezien de ware toedracht van de toename in intratendineuze doorbloeding ter hoogte van de patellaire apex, in relatie tot verbetering in kliniek en functionaliteit, nooit eerder onderzocht werd en het hier slechts een pilootstudie betreft, is verder onderzoek inzake dit onderwerp absoluut noodzakelijk om tot gefundeerde conclusies en suggesties te komen.
Bibliografie
Ackerman, P. (2001). Sensory neuropeptides in Achilles tendinosis. Int Soc Arthrosc Knee Surg Ortho Sports Med, (17), 516.
Ackerman, P., Ahmed, M., Kreichbergs, A. (2002). Early nerve regeneration after Achilles tendon rupture: a prerequisite for healing? A study in the rat. J Orth Res, (20), 849-856.
Akbas, E., Atay, A.O., Yüksel. (2011). The effects of additional kinesio taping over exercise in the treatment of patellofemoral pain. Acta Orthop Traumatol Turc. 45(5)335-41
Alfredson, H., Öhberg, L. (2005). Neovascularisation in chronic painful patellar tendinosis – promising results after sclerosing neovessels outside the tendon challenge the need for surgery. Knee Surg Sports Traumatol Arthrosc, (13), 74-80.
Alfredson, H., Thorsen, K. & Lorentzon, R. (1999). In situ microdialysis in tendon tissue: high levels of glutamate, but not prostaglandin E2 in chronic Achilles tendon pain. Knee Surg Sports Traumatol Arthrosc, (7), 378-381.
Alfredson, H., Pietila, T., Jonsson, P. (1998). Heavy load eccentric calf muscle training for the treatment of chronic achilles tendinosis. Am J Sports Med 26:360-6.
Almekinders, L.C., Vellema, J.H., Weinhold, P.S. (2002). Strain patterns in the patellar tendon and the implications for patellar tendinopathy. Knee surgery sports traumatology arthroscopy, (10), 2-5.
Almekinders, L.C., Weinhold, & Maffulli, N. (1998). Etiology, diagnosis, and treatment of tendonitis: an analysis of the literature. Med Sci Sports Exerc , (30),1183-1190.
Almekinders, L.C., Weinhold & Maffulli, N. (2003). Compression etiology in tendinopathy. Clinical Sports Medicine, (22), 703-710.
Andersson, G., Danielson, P., Alfredson, H. & Forsgren, S. (2008). Presence of substance P and the neurokinin-1 receptor in tenocytes of the human Achilles tendon. Regul Pept, (150), 81-87.
Arnoczky, S.P., Lavagnino, M., Whallon, J.H., Hoonjan, A. (2002). In situ cell nucleus deformation in tendons under tensile load; a morphological analysis using confocal laser microscopy. Journal of orthopaedic research, (20), 19-35.
Arnoczky, S.P., Tian, T., Lavagnino, M., Gardner, K., Schuler P. & Morse, P. (2002). Activation of stress-activated protein kinases (SAPK) in tendon cells following cyclic strain: the effects of strain frequency, strain magnitude, and cytostolic calcium. Journal of orthopaedic research, (20), 947-952.
Ästrom. (1998). Partial rupture in Achilles tendinopathy. A retrospective analysis of 342 cases. Acta Orthop Scand, 69(4), 404-407.
Bahr, R., Fossan, B., Loken, S, Engebretsen, L. (2006). Surgical treatment compared with eccentric training for patellar tendinopathy (jumper’s knee). A randomized controlled trial. J Bone Joint Surg Am, (88), 1689-1698.
Basso, O., Amis, A.A., Race, A., Johnson, D.P. (2002). Patellar tendon fiber strains: their differential responses to quadriceps tension. Clinical orthopaedics and related research, (400), 246)253.
Benjamin, M., Kumai, Milz, Boszczyk B.M., Boszczyk A.A. & Ralphs. (2002). The skeletal attatchment of tendons: tendon entheses. Comp Biochem Phys A Mol Integr Physiol, (133), 931-945
Benjamin, M. & Ralphs, J.R. (1998). Fibrocartilage in tendons and ligaments - an adaptation to compressive load. Journal of anatomy, (193), 481-494.
Benjamin, M., Toumi, H., Ralphs, J.R., Bydder,G., Best T.M. & Milz, S. (2006). Where tendons and ligaments meet bone: attatchment sites (‘entheses’) in relation to exercise and/or mechanical load. J Anat, 208, 471-490.
Bergstrom, K.A., Brandseth, K., Fretheim, S., Tvilde, K. & Ekeland, A., (2001). Activity-related knee injuries and pain in athletic adolescents. Knee surgery and sports traumatology arthroscopy, (9), 146-150.
Blazina, M. E., Kerlan, R. K., Jobe, F. W., Carter, V. S., Carlson, G. J. (1973). Jumper’s knee. Orthop Clin North Am, 1973, 4(3), 665-678.
Bleakley, C., McDonough, S., & LacAuley, D. (2006). Cryotherapy for acute ankle sprains: a randomised controlled study of two different icing protocols. Br J Sports Med , 40:700-705.
Cannell, L. J., Taunton, J.E., Clement, D.B., Smith, C., Khan, K.M. (2001). A randomised clinical trial of the efficacy of drop squats or leg extension/leg curl exercises to treat clinically diagnosed jumper’s knee in athletes: pilots study; Br J Sports med 2001;35:60-4.
Coleman, B., Khan, M., Muffulli, N., Cook, J. & Wark, J. (2000). Studies of surgical outcome after patellar tendinopathy: clinical significance of methodological deficiencies and guidelines for future studies. Victorian Institue of Sport Tendon Study Group. Scand J Med Sci Sports, (10), 2-11.
Colosimo, A.J. & Basset, F.H. (1990). Jumper’s knee: diagnosis and treatment. Orthopaedic Reviews, (29), 139-149.
Cook, J.L., Bass, S. & Black, J. (2007). Hormone therapy is associated with smaller Achilles tendon diameter in active post-menopausal women. Scan J Med Sci Sports, (17), 128-132.
Cook, L., Feller, J., Bonar, S., Khan, K. (2004). Abnormal tenocyte morphology is more prevalent than collagen disruption in asymptomatic athletes' patellar tendon. J Orthop Res. 2004 Mar; 22(2): 334-8.
Cook, J., & Khan, K. (2001). What is the most appropriate treatment for patellar tendinopathy? Br J Sports Med , 35: 291-294.
Cook, J., Khan, M., Harcourt, P., Grant, M., Young, D. & Bonar, S. (1997). A cross sectional study of 100 athletes with jumper’s knee managed conservatively and surgically. The Victorian Institute of Sport Tendon Study Group. British Journal of Sports Medicine, (31), 332-336.
Cook, J.L., Khan, K., Harcourt, P., Kiss, Z., Fehrmann, M., Grifftihs, L., Wark, J. (1998). Patellar tendon ultrasonography in asymptomatic active athletes reveals hypoechoic regions: a study of 320 tendons. Victorian Institute of Sport Tendon Study Group. Clinical Journal of Sports Medicine, (8), 73-77.
Cook, J.L., Khan, K.M., Kiss, Z.S., Coleman, B.D., Griffiths, L. (2001). Asymptomatic hypo-echoic regions on patellar tendon ultrasound: A 4-year clinical and ultrasound followup of 46 tendons. Scandinavian Journal of Medicine and Science in Sports , (11), 321-327.
Cook, J.L., Khan, K., Kiss, Z. & Griffiths, L. (2000). Patellar tendinosis in junior basketball players: A controlled clinical and ultrosonographic study of 268 tendons in players aged 14-18 years. Scand J Med Sci Sports, (10), 216-230.
Cook, J.L. & Purdam. (2003). Rehabilitation of lower limb tendinopathies. Clinical Sports Medicine, (22), 777-789.
Coombes, B., Bisset, L. & Vincenzino, B. (2010). Efficacy and safety of corticosteroid injections and other injections for the management of tendinopathy: a systematic review of randomised controlled trials. Lancet, (376), 1751-1767.
Crisp, T., Khan, F., Padhiar, N., Morrissey, D., King, J., Jalan, R., Maffulli, N. & Chan O. (2008). High volume ultrasound guided injections at the interface between the patellar tendon and Hoffa’s body are effective in chronic patellar tendinopathy. A pilot study. Disability Rehabilitation, (30), 1625-1634.
Crossley, K., Thancanamootoo, K., Metcalf, B., Cook, J., Purdam, C. & Warden, S. (2007). Clinical features of patellar tendinopathy and their implications for rehabilitation. Journal of orthopaedic research, september 2007, 1164-1175.
Culvenor, A.G., Cook, J.L., Warden, S.J. & Crossley, K.M. (2011). Infrapatellar fat pad size, but not patellar alignment, is associated with patellar tendinopathy. Scan J Med Sci Sports.
Danielson, P. (2008). Reviving the ‘biochemical’ hypothesis for tendinopathy: new findings suggest the involvement of locally produced signal substances. British Journal of Sports medicine, 2009, (43), 265-268.
Danielson, P., Andersson, G., Alfredson, H. & Forsgren, S. (2008). Marked sympathetic component in the perivascular innervation of the dorsal paratendinous tissue of the patellar tendon in arthroscopically treated tendinosis patients. Knee surgery sports traumatology arthroscopy, (16), 621-626.
Devan, M.R., Pescatello, L.S., Faghri, P. & Andersson, J. (2004). A prospective study of overuse knee injuries among female athletes with muscle imbalances and structural abnormalities. Journal of athletic training, (39), 263-267.
Dillon, E., Erasmus, P., Müller, J., Scheffer, C. & de Villiers, R. (2008). Differential forces within the proximal patellar tendon as an explanation for the characteristic lesion of patellar tendinopathy: an in vivo descriptive experimental study. The American journal of sports medicine, (36), 2119-2127.
Edwards, S., Steele, J., McGhee, D., Beattle, S., Purdam, C. & Cook J. (2010). Landing strategies of athletes with an asymptomatic patellar tendon abnormality. Medicine and science in sports and exercise, (42), 2072-2080.
Fenwick, S.A., Hazleman B.L. & Riley, G.P. (2002). The vasculature and its role in the damaged and healing tendon. Arthritis Res, (4), 252-260.
Franklyn-Miller, A., Falvey, E. & McCrory, P. (2009). Fasciitis before tendinopathy: does the anatomy hold the key? British Journal of Sports Medicine, (43), 887-889.
Fredberg, U., & Bolvig, L. (1999). Juper’s knee: review of literature. Scandinavian Journal of Medicine & Science in Sports. Scandinavian Journal of medicine & Science in Sports , 9(2),66-73.
Fu, S.C., Wang, W., Pau, H.M., Wong, Y.P., Chan, K.M., Rolf, C.G. (2002). Increased expression of transforming growth factor-beta1 in patellar tendinosis. Clinical Orthopedics, (400), 74-183.
Gaida, J., Cook, J. & Bass, S. (2008). Adiposity and tendinopathy. Disablity Rehabilitation, 9 mai 2008.
Gotoh, M., Hamada, K., Yamakawa, H., Inoue, A., Fukuda, H. (1998). Increased substance P in subacromial bursa and shoulder pain in rotator cuff diseases. J Orthop Res, (16), 618-621.
Grau, S., Maiwald, C., Krauss, I., Axmann, D., Janssen, P. & Horstmann, T. (2008). What are causes and treatment strategies for patellar tendinopathy in female runners? Journal of Biomechanics, (41), 2042-2046.
Hamilton, B. & Purdam, C. (2004). Patellar tendinosis as an adaptive process: a new hypothesis. British Journal of Sports Medicine, (38), 758-761.
Hansen, P., Aagaard, P., Kjaer, M., Larsson , B. & Magnusson, S. (2003). Effect of habitual running on human Achilles tendon load-deformation properties and cross-sectional area. Journal of applied physiology, (95), 2375-2380.
Haraldsson, B., Aagaard, P., Krogsgaard, M., Alkjaer, T., Kjaer, M. & Magnusson, S. (2005). Region-specific mechanical properties of the human patella tendon. Journal of applied physiology, (98), 1006-1012.
Hoksrud, A., Öhber, L., Alfredson, H. & Bahr, R. (2006). Ultrasound-guided sclerosis of neovessels in painful chronic patellar tendinopathy. A randomized controlled trial. American Orthopaedic Society for Sports Medicine, 34(11), 1738-1746.
Hubbard, T.J., Denegar, C.R. (2004). Does cryotherapy improve outcomes with soft tissue injury? J Athl Train. Sept 39(3):278-279
Ireland, D., Harral, R., Curry, V., Hallaway, G., Hackny, R., Hazleman, B., Riley, G. (2001). Multiple changes in gene expression in chronic human Achilles tendinopathy. Matrix Biology, (20), 159-169.
James, S., Ali, K., Pocock, C. (2007). Ultrasound guided dry needling and autologous blood injection for patellar tendinosis. British Journal of Sports Medicine, (41), 518-521.
Johnson, D.P. (1998) Arthroscopic surgery for patellar tendonitis: A new technique. Arthroscopy, 14(1), 44
Jonsson,D.P., Alfredson, H., 2005, Superior results with eccentric compared to concentric quadriceps training in patients with Jumper’s knee: a prospective randomiseed study. Br J Sports med 2005;39:847-50
Johnson, D.P., Wakeley, C.J., Watt I. (1996). Magnetic resonance imaging of patellar tendonitis. J Bone Joint Surg Br, 78(3), 452-457
Johnson, G.A., Tramaglini, D.M., Levine, R.E., Ohno, K., Choi, N.Y. & Woo, S.L.Y. (1994). Tensile and visco-elastic properties of the human patellar tendon. Journal of orthopaedic research, (12), 796-803.
Jozsa, L. & Kannus, P. (1997). Human tendons: Anatomy, physiology and pathology. Champaign, IL: Human Kinetics.
Jozsa, L., Kvist, M. Balint, B.J., Reffy, A., Jarvinen, M., Lehto, M. & Barzo, M. (1989). The role of recreational sport activity in Achilles-tendon rupture - a clinical, pathoanatomical and sociological study of 292 cases. American journal of sports medicine, (17), 338-343.
Kannus, P. (1997). Etiology and pathophysiology of chronic tendon disorders in sports. Scandinavian journal of medicine and science in sports, (7), 78-85.
Kannus, P., Aho H., Jarvinen, M. & Niittymaki, S. (1987). Computerized recording of visits to an outpatient’s sports clinic. American Journal of Sports Medicine, (15), 79-85.
Kannus, P., Jozsa, L. (1991). Histopathological changes preceding spontaneous rupture of tendon. A controlled study of 891 patients. Journal of bone and joint surgery (Am), (73), 1507-1525.
Kaufman, K., Brodine, S., Shaffer, R., Johnson, C. & Cullison, T. (1999). The effect of foot structure and range of motion on musculoskeletal overuse injuries. American Journal of Sports Medicine, (27), 585-593.
Ker, R.F. (2002). The implications of the adaptable fatigue quality of tendons for their construction, repair and function. Comparative biochemistry and physiology a-molecular and integrative physiology, (133)4, 987-1000.
Kettunen, J.A., Kvist, M., Alanen, E. & Kujala,U.M. (2002). Long-term prognosis for jumper’s knee in male athletes. A prospective follow-up study. American Journal of Sports Medicine , (30), 689-692.
Khan, K.M., Cook, J.L. & Bonar, S. (1999). Histopathology of common tendinopathies. Update and implications for clinical management. Sports Med, (27), 393-408.
Khan, K.M, Cook, J.L., Kannus, P., Maffulli, N. & Bonar, S. (2002). Time to abandon the “tendinits” myth. British Medical Journal, (324), 626-627.
Khan, K.M., Cook, J.L., Kiss, Z.S., Visentini, P., Fehrmann, M., Harcourt, P., Tress, B.M. & Wark, J.D. (1997). Patellar tendon ultrasonography and jumper’s knee in elite female basketball players: a longitudinal study. Clinical Journal of Sports Medicine, (7), 199–206.
Khan, K.M., Maffulli, N., Coleman, B.D., Cook, J.L., Taunton, J.E. (1998) Patellar tendinopathy: some aspects of bsic science and clinical management. Br J Sports Med. 32 (4)346-355
Khan, K.M., Cook, J.L., Maffulli, N. & Kannus, P. (2000a). Where is the pain comming from in tendinopathy? It may be biochemical, not only structural, in origin. Britisch Journal of Sports Medicine, (34), 81-83.
Khan, K.M., Cook, J.L., & Taunton, J. (2000b). Overuse tendinosis, not tendinitis. Part1: a new paradigm for a dificult clinical problem. Physical Sportsmedicine , (28) 38-48.
Khan, K.M, Cook, J.L., & Taunton, J. (2000c). Overuse tendinosis, not tendinitis. Part2: applying the new approach to patellar tendinopathy. Physical Sportsmedicine , (28), 31-46.
Khan, K.M., Visentini, P.J., Kiss, Z.S., Desmond, P.M., Coleman, B.D., Cook, J.L., Tress, B.M., Wark J.D. & Forster, B.B. (1999). Correlation of ultrasound and magnetic resonance imaging with clinical outcome after patellar tenotomy: Prospective and retrospective studies. Victorian Institute of Sport Tendon Study Group. Clinical journal of sports medicine, (9), 129-137.
Kjaer, M., Langberg, H., Skovgaard, D., Olesen, J., Bulow, J., Krogsgaard, M. & Boushel, R. (2000). In vivo studies of peritendinous tissue in exercise. Scandinavian journal of medicine and science in sports, (10), 326-331.
Knobloch, K. (2008). The role of tendon microcirculation in Achilles and patellar tendinopathy. Journal of orthopaedic surgery and research, 3:18.
Knobloch, K., Grasemann, R., Spies, M., & Vogt, P. M. (2007). Intermittent KoldBlue cryotherapy of 3x10 min changes mid-portion Achilles tendon microcirculation. Br J Sports Med , 41:e4.
Knobloch, K., Grasemann, R., Spies, M., & Vogt, P. M. (2008). Midportion Achilles Tendon Microcirculation After Intermittent Combined Cryotherapy and Compression Compared With Cryotherapy Alone. Am J Sports Med , vol. 36 no.11 2128-2138.
Knobloch,K., Kraemer, R., Lichtenberg, A., Jagodzinski, M., Gossling T., Richter, M., Zeichen, J., Hufner , T. & Krettek, C. (2006). Achilles tendon and paratenon microcirculationin midportion and insertional tendinopathy in athletes. American Journal of Sports Medicine, (34), 92-97.
Kongsgaard, M., Kovanen, V., Aagaard, P., Doessing, S., Hansen, P., & Laursen, A. H. (2009). Corticosteroid injections, eccentric decline squat training and heavy slow resistance training in patellar tendinopathy. Scand J Med & Science in Sports , (19) 790-802.
Kountouris, A. (2003). Rehabilitation of Achilles and patellar tendinopathies. Best Pract Res Clin Rheum, (21), 295-316.
Krauss, I., Grau, S., Rombach, S., Janssen, P., Maiwald, C., Axmann, D. & Horstmann, T. (2007). Association of strength with patellar tendinopathy in female runners. Isokinetics and exercise science, (15), 217-223.
Kujala, U., Kvist, M. & Osterman, K. (1986). Knee injuries in athletes: review of exertion injuries and retrospective study of outpatients sports clinic material. Sports Medicine, (3), 447-460.
Kvist, M., Jozsa, L., Järvinen, M., Kvist, H. (1985). Fine structural alternations in chronic Achilles paratenonitis in athletes. Path Res Pract, (180), 416-423.
Kvist, M., Jozsa, L., Järvinen, M. & Kvist, H. (1987). Chronic Achilles paratenonintis in athletes: A histological and histochemical study. Pathology, (19), 1-11.
LaStayo, P., Woolf, J., Lewek, M., Snyder-Mackler, L., Reich, T., & Lindstedt, S. (2003). Eccentric muscle contractions: their contribution to injury, prevention, rehabilitation and sport. J Orthop Sports Phys Ther , 33(10) 557-571.
vLian, O., Refsnes, P., Engebretsen, L., Bahr, B. (2003). Performance characteristics of volleyball players with patellar tendinopathy. American Journal of Sports Medicine, (31), 408-413.
Lian, O., Dahl, J., Ackermann, P., Frihagen, F., Engebretsen, I. & Bahr, R. (2006). Pronociceptive and antinociceptive neuromediators in patellar tendinopathy. American Journal of Sports Medicine, (34), 1801-1808.
Lichtwark, G. & Wilson, A. (2005) In vivo mechanical properties of the human Achilles tendon during one-legged hopping. Journal of experimental biology, (208) 24, 4715-4725.
Lorbach, O., Diamantopoulos, A., Kammerer, C.P. & Paessler, H.H. (2008). The influence of the lower patellar pole in the pathogenesis of chronic patellar tendinopathy. Knee Surg Sports Traumatol Athrosc, (16), 348-352.
Lui, P., Chan, L., Fu, S. & Chan, K. (2010). Expression of sensory neuropeptides in tendon is associated with failed healing and activity-related tendon pain in collagenase-induced tendon injury. American Journal of Sports Medicine, 38(4), 757-763.
Maffulli, N., Testa, V. & Capasso, G. (2004). Similar histopathological picture in males with Achilles and patellar tendinopathy. Med Sci Sports Exerc, (36), 1470-1475
Maffulli, N., Wong, J. & Almekinders, L. (2003). Types and epidemiology of tendinopthy. Clinical Sports Medicine, (22), 675-692.
Maganaris, C.N., Narici, M.V., Almekinders, L.C. & Maffulli, N. (2004). Biomechanics and pathophysiology of overuse tendon injuries - Ideas on insertional tendinopathy. Sports Medicine, (34), 1005-1017.
Magra, M. & Maffulli, N.. (2008). Genetic aspects of tendinopathy. J Sci Med Sports, (11), 243-247.
Malliaras, P. & Cook, J. (2000). Reduced ankle dorsiflexion range may increase the risk of patellar tendon injury among volleyball players. J Sci Med Sports, (9), 304-309.
Malliaras, P. & Cook, J. (2006). Patellar tendons with normal imaging and pain status over a volleyball season. Clinical Journal of Sports Med, (16), 388-391.
Malliaras, P., Cook, J. & Kent, P. (2007). Anthropometric risk factors for patellar tendon injury among volleyball players. British Journal of Sports Medicine, (41), 259-263.
Mokone, G., Gayjar, M., September, A.V., Schwellnis, M.P., Greeberg, J., Noakes, T.D., Collins, M. (2005). The guanine-thymine dinucleotide repeat polymorphism within the tenascin-C geneis associated with Achilles tendon injuries. American Journal of Sports medicine, (33), 1016-1021.
Myllymaki, T., Bondestam, S., Suramo, I., Cederberg, A., Peltokallio, P. (1990). Ultrasonography of jumper’s knee. Acta Radiologica, (31), 147–149.
Newell, S. & Bramwell, S. (1984). Overuse injuries to the knee in runners. Physical Sportsmedicine, (12), 81-86.
Ohberg, L. & Alfredson, H. (2003). Sclerosing therapy in chronic Achilles tendon insertional pain-results of a pilot study. Knee Surg Sports Traumatol Atrhrosc, (11), 339-343.
Ohberg, L., Lorentzon, R. & Alfredson, H. (2001). Neovascularisation in Achilles tendon with painful tendinosis but not in normal tendons: an ultrasonographic investigation. Knee Surg Sports Traumatol Arthrosc, (9), 233-238.
Pedrelli, A., Stecco, C., & Day, J. (2009). Treating patellar tendinopathy with Fascial Manipulation. Journal of Bodywork and Movement Therapies , 13,73-80.
Peers, K. & Lysens R. (2005). Patellar tendinopathy in athletes – Current diagnostic and therapeutic recommendations. Sports medicine, (35), 71-87.
Pellechia, G., Hamel, H., & Behnke, P. (1994). Treatment of infrapatellar tendinitis: a combination of modalities and transverse friction massage versus iontophoresis. Journal of sports rehabilitation , 1315-1345.
Pierets K., Verdonk R., De Muynck M. & Lagast J. (1999). Jumper’s knee: postoperative assessment. A retrospective clinical study. Knee Surgery, Sports Traumatology and arthroscopy, (7), 239-242.
Popp, J.E., Yu, J.S. & Keading, C.C. (1997). Recalcitrant patellar tendinitis. Magnetic Resonance Imaging, histologic evaluation and surgical treatment. Am J Sports Med, (25), 218-222.
Pufe, T., Peterson, W.J., Mentlein, R. & Tillmann, B.N. (2005). The role of vasculature and angiogenesis for the pathogenesis of degenerative tendon disease. Scan J Med Sci Sports, 15(4), 211-222.
Purdam, C.R., Johnsson, P., Alfredson, H., Lorentzon, R., Cook, J.L., Khan, K.M.(2004) A pilot study of the eccentric decline squat in the management of painful chronic patellar tendinopathy. British Journal of Sports Medicine, Aug. 2004;Vol. 38, No. 4, (395-397),
Ramos, L., Teixeira de Carvalho, R., Garms, E., Navarro, M., Abdalla, R. & Cohen, M. (2008). Prevalence of pain on palpation of the inferior pole of the patella among patients with complaints of knee pain. Clinics 2009, (64), 199-202.
Rees, J.D., Maffulli, N. & Cook, J.L. (2010). Management of tendinopathy. Am J Sports Med. 2009. Sep, 37(9):1855-67.
Rees, J.D., Wilson, A.M., Wolman R.L. (2006). Current concepts in the management of tendon disorders. Rheumatology, (45)5, 508-521.
Renstrom, P. (1991). Sports traumatology today: a review of common current sports injury problems. Ann Chir Gynaecol, (80), 81-93.
Rodineau, J. & Simon, L. (1987). Microtraumatologie du sport et surmenage articulaire. Parijs, New York, Barcelona, Milaan, Mexico, Soa Paula: Masson.
Roels, J., Martens, M., Mulier, J., Burssens, A. (1978). Patellar tendinitis (jumper’s knee). Am J Sports Med. 6:362-368.
Rufai, A., Ralphs, J.R. & Benjamin, M. (1995). Structure and histopathology of the insertional region of the human achilles tendon. J Orthop Res, (13), 585-593.
Rutland, M., O'Connell, D., Brismée, J.-M., Sizer, P., Apte, G., & O'Connell, J. (2010). Evidence-supported rehabilitation of patellar tendinopathy. North American J of Sports Physical Therapy , volume5, number3: 166-178.
Sarimo, J. et al. (2006). Distal patellar tendinosis: an unusual form of jumper’sknee. Knee Surg Sports Traumatol Arthrosc, 2007, (15), 54-57.
Schmid, Hodler, Philipp, Duewell, Jacob & Romero. (2002). Is impingement the cause of jumper’s knee? Dynamic and Static Magnetic Resonance Imaging of Patellar Tendinitis in an Open-Configuration System. Am J Sports Med, (30), 388.
Schubert, T., Weidler, C., Lerch, K., Hofstadter, F. & Straub, R. (2005). Achilles tendinosis is associated with sprouting of substance P positive nerve fibers. Ann Rheum Dis, (64), 1083-1086.
Sheenan, F., Drace, J. (2000). Human patellar tendon strain - A noninvasive, in vivo study. Clinical orthopaedics and related research, (370), 201-207.
Stanish, W.D., Curwin, S. (1984) Tendinitis: its etiology and treatment. Lexington, MA: Coollamore Press.
Stasinopoulos, D., Stasionpoulos, I. (2004). Comparison of effects of exercise programme, pulsed ultrasound and transverse friction in treatment of chronic patellar tendinopathy. Clin Rehabil, 2004, (18,) 347-352.
Tan, S. & Chan, O. (2008). Achilles and patellar tendinopathy: Current understanding of pathophysiology and management. Disability and rehabilitation, (30), 20-22.
Torstensen, E.T., Bray, R.C. & Wiley, J.P. (1994). Patellar tendinitis: a review of current concepts a,d treatment. Clinical Journal of Sports Medicine, (4), 77-82.
Van der Worp, H., van Ark, M., Roerink, S., Pepping, G., van de Akker-Scheek, I. & Zwerver, J. (2011). Risk factors for patellar tendinopathy: a systematic review of the literature. British journal of sports medicine, (45), 446-452.
Visnes, H., & Bahr, R. (2007). The evolution of eccentric training as treatment for patellar tendinopathy (jumper"s knee): a critical review of exercise programmes. Br J Sports Med , (41), 217-223.
Visnes, H., Hoksrud, A., Cook, J., Bahr, R. (2005) No effect of eccentric training on jumper’s knee in volleyball players during the competitive season: A Randomized Clinical Trial. Clin. Journal of Sports Medicine, 2005; No. 15, (227-234).
Visentini, P.J., Khan, K.M., Cook, J.LL, Kiss, Z.S., Harcourt, P. & Wark, J.D. (1998). The VISA score: an index of severity of symptoms in patients with jumper’s knee (patellar tendinosis). Journal of science and medicine in sports, (1), 22-28.
Vogel, Ordog, Pogay & Olak. (1993). Proteoglycans in the compressed region of the human tibialis posterior tendon and in ligaments. J Orthop Res, (11), 68-77
Warden, S. J., & Bruckner, P. (2003). Patellar tendinopathy. Clinical Sports Medicine , (22) 743-759.
Willberg, L. Sunding, K. Ohberg, L., Forssblad, M., Alfredson, H. (2007) Treatment of jumper’s knee: promising short-term results in a pilot-studyusing a new arthroscopic approach based on imaging findings. Knee Surg Sports Traumatol Arthrosc, (15), 676-681.
Witvrouw, E., Bellemans, J., Lysens, R., Danneels, L. & Cambier, D. (2001). Intrinsic risk factors for the development of patellar tendinitis in an athletic population. The American Journal of Sports Medicine, (29), 190-195.
Witvrouw, E., Lorent, M., Va, Assche, D. (2008). Oefentherapie bij knieaandoeningen.: Centraal boekhuis
Wyssa, B., De Gautard, R. & Fritschy, D. (1992). L’apport de l’échographie dans la tendinite rotulienne, ou ‘jumper’s knee’. Journal de Traumatologie du Sport,
1992,(9), 140-149.
Young, M.A., Cook, J.L., Purdam, C.R., Kiss, Z.S., Alfredson, H.(2005). Eccentric decline squat protocol offers superior results at 12 months compared with traditional eccentric protocol for patellar tendinopathy in volleyball players. British Journal of Sports Medicine, Feb. 2005; Vol. 39, No. 2 (102-105).
Zwerver, J., Bredeweg, S.W., Hof, A.L. (2007). Biomechanical analysis of the single -leg decline squat. Br J Sports Med. 2007 41(4):264-268.
Zwerver, J., Kramer, T. & van den Akker-Scheek. (2009). Validity and reliability of the Dutch translation of the VISA-P questionnaire for patellar tendinopathy. BMC musculoskeletal disorders, (10), 102.
