Impaired Isometric, Concentric, and Eccentric Rate of Torque Development at the Hip and Knee in Patellofemoral Pain

Abstract

Impaired isometric, concentric, and eccentric rate of torque development at the hip and knee in patellofemoral pain. J Strength Cond Res 35(9): 2492-2497, 2021-The aims of this study were to compare maximal muscle strength and rate of torque development (RTD) of knee extensor and hip abductor during isometric, concentric, and eccentric contractions between women with and without patellofemoral pain (PFP). Thirty-eight women with PFP (PFPG) and 38 pain-free women (CG) participated in this study. Isometric, concentric, and eccentric maximal torque and RTD of knee extensor and hip abductor were assessed using an isokinetic dynamometer. Rate of torque development was calculated as the change in torque over the change in time from torque onset to 30, 60, and 90% of the maximal torque (RTD 30% , RTD 60% , and RTD 90% ) during isometric, concentric, and eccentric contractions. PFPG had lower isometric, concentric, and eccentric knee extensor maximal torque (29.9, 28.3, and 26.7%) compared with the CG. For knee extensor RTD, PFPG had slower isometric RTD 30% (17.8%), RTD 60% (21.5%), and RTD 90% (23.4%); slower concentric RTD 30% (35.7%), RTD 60% (29.3%), and RTD 90% (28.2%); and slower eccentric RTD 30% (20.5%), RTD 60% (25.2%), and RTD 90% (22.5%) compared with the CG. PFPG had lower isometric, concentric, and eccentric hip abductor maximal torque (28.3, 21.8, and 17%) compared with the CG. For hip abductor RTD, PFPG had slower isometric RTD 30% (32.6%), RTD 60% (31.1%), and RTD 90% (25.4%); slower concentric RTD 90% (11.5%); and slower eccentric RTD 30% (19.8%), RTD 60% (26.4%), and RTD 90% (24%) compared with the CG. In conclusion, women with PFP presented deficits in both maximal strength and RTD of knee extensor and hip abductor during isometric, concentric, and eccentric contractions, which highlight the potential importance of addressing different aspects of muscle function through exercise therapy.

Karakteristike jakosti kuka, gležnja i trupa kod osoba s patelofemoralnom boli

“…Pregled osnovnih podataka studija koje su proučavale maksimalnu voljnu izometričku kontrakciju mišića kuka i trupa kod osoba s patelofemoralnom boli u usporedbi s kontrolnom grupom (KG). 16,17,19 Ustanovljeno je da u žena s PFB-om vidljiv deficit MVIC-a abduktora kuka od 15 % do 20 % (p < 0,002) u usporedbi s KGom. 19 Drugi su autori na uzorku (n = 43) žena s PFB-om i bez PFB-a ocjenjivali povezanost dinamičnoga valgusa koljena i MVIC-a mišića kuka.…”

“…Uzimajući u obzir dokazano višu incidenciju PFB-a u žena, ne iznenađuje činjenica da različite studije uspoređuju MVIC abduktora kuka u žena s PFB-om i bez PFBa, 16,17,19 dok je onih koji potonje proučavaju u muškaraca osjetno manje. 20,21 Rezultati navedenih istraživanja izvještavaju o smanjenoj vrijednosti MVIC-a abduktora kuka u žena s PFB-om deficit dosegnuo 27,9 % (p < 0,01) u odnosu na KG bez PFB-a.…”

“…Ustanovljeno je da, iako postoje značajne razlike među skupinama za sve tri vrste mišićne kontrakcije, najizraženije su u slučaju MVIC-a. 17 Za razliku od žena s PFB-om, muškarci s istim bolnim sindromom nisu pokazali smanjene vrijednosti MVIC-a abduktora kuka. 20,21 Jedna od proučavanih studija uključila je 102 muškarca s PFB-om i bez PFB-a.…”

“…U čeonoj je ravnini kod žena s PFB-om vidljivo smanjenje MVIC-a abduktora kuka. 1,16,17 S obzirom na razlike među spolovima po pregledu literature pokazala se potreba za dodatnim istraživanjima koja bi proučavale MVIC na muškom uzorku s PFB-om te usporedila dobivene rezultate sa ženskim uzorkom iste problematike. Stoga je za zaokruživanje slike jakosti mišića u čeonoj ravnini potrebno identificirati potencijalne deficite jakosti pri muškom spolu.…”

“…Također, važno je napomenuti da su žene s PFB-om pokazale statistički značajno smanjenje MVIC-a ekstenzije koljena. 17 Kod muškaraca postoji nedostatak istraživanja koja bi sa sigurnošću potvrdila ili opovrgnula takve tvrdnje.…”