Principal component based analysis of biomechanical inter-trial variability in individuals with chronic ankle instability



      Biomechanical variability during movement may influence joint stability in individuals with chronic ankle instability (CAI). The purpose of this study was to compare the kinematic and the kinetic inter-trial variability between healthy and CAI individuals.


      Eleven individuals with CAI and 11 matched controls performed five repetitions of a single-leg landing task. Biomechanical data were collected from 100 ms before to 200 ms after touchdown, and were used to calculate touchdown angles, peak angles and moments at the ankle joint in the frontal and sagittal planes. In addition, principal component analyses were used to quantify kinematic and kinetic patterns in the same planes across the 300 ms time window. Five trial averages and inter-trial variability were calculated for all variables for each subject. Independent t-tests were used to compare variables between groups.


      The CAI group displayed greater inter-trial variability for principal component scores in the sagittal and frontal planes. The sagittal plane principal component captured a phase shift in plantar–flexion motion before touchdown, while the frontal plane principal component captured the general magnitude of motion during the entire movement. The CAI group therefore exhibited greater inter-trial variability in the sagittal plane before touchdown and in the frontal plane during the entire movement.


      While average motions did not differ between groups, the CAI group displayed greater kinematic inter-trial variability when analyzed with the principal component analysis. More variable joint motions may indicate less dynamic stability in the CAI group, which may originate from greater ligamentous laxity or diminished neuromotor control.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Clinical Biomechanics
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Brown C.
        Foot clearance in walking and running in individuals with ankle instability.
        Am. J. Sports Med. 2011; 39: 1769-1776
        • Brown C.
        • Padua D.
        • Marshall S.W.
        • Guskiewicz K.
        Individuals with mechanical ankle instability exhibit different motion patterns than those with functional ankle instability and ankle sprain copers.
        Clin. Biomech. 2008; 23: 822-831
        • Brown C.N.
        • Padua D.A.
        • Marshall S.W.
        • Guskiewicz K.M.
        Variability of motion in individuals with mechanical or functional ankle instability during a stop jump maneuver.
        Clin. Biomech. 2009; 24: 762-768
        • Brown C.
        • Bowser B.
        • Simpson K.J.
        Movement variability during single leg jump landings in individuals with and without chronic ankle instability.
        Clin. Biomech. 2012; 27: 52-63
        • Daffertshofer A.
        • Lamoth C.J.
        • Meijer O.G.
        • Beek P.J.
        PCA in studying coordination and variability: a tutorial.
        Clin. Biomech. 2004; 19: 415-428
        • Delahunt E.
        • Monaghan K.
        • Caulfield B.
        Altered neuromuscular control and ankle joint kinematics during walking in subjects with functional instability of the ankle joint.
        Am. J. Sports Med. 2006; 34: 1970-1976
        • Delahunt E.
        • Monaghan K.
        • Caulfield B.
        Changes in lower limb kinematics, kinetics, and muscle activity in subjects with functional instability of the ankle joint during a single leg drop jump.
        J. Orthop. Res. 2006; 24: 1991-2000
        • Drewes L.K.
        • McKeon P.O.
        • Paolini G.
        • Riley P.
        • Kerrigan D.C.
        • Ingersoll C.D.
        • et al.
        Altered ankle kinematics and shank-rear-foot coupling in those with chronic ankle instability.
        J. Sport Rehabil. 2009; 18: 375-388
        • Ferran N.A.
        • Maffulli N.
        Epidemiology of sprains of the lateral ankle ligament complex.
        Foot Ankle Clin. 2006; 11: 659-662
        • Fong D.T.
        • Hong Y.
        • Shima Y.
        • Krosshaug T.
        • Yung P.S.
        • Chan K.M.
        Biomechanics of supination ankle sprain: a case report of an accidental injury event in the laboratory.
        Am. J. Sports Med. 2009; 37: 822-827
        • Hale S.A.
        • Hertel J.
        Reliability and sensitivity of the foot and ankle disability index in subjects with chronic ankle instability.
        J. Athl. Train. 2005; 40: 35-40
        • Hass C.J.
        • Bishop M.D.
        • Doidge D.
        • Wikstrom E.A.
        Chronic ankle instability alters central organization of movement.
        Am. J. Sports Med. 2010; 38: 829-834
        • Hertel J.
        Functional anatomy, pathomechanics, and pathophysiology of lateral ankle instability.
        J. Athl. Train. 2002; 37: 364-375
        • Hertel J.
        The complex etiology of lateral ankle instability.
        J. Orthop. Sports Phys. Ther. 2005; 35: 9-10
        • Hubbard T.J.
        • Hertel J.
        Mechanical contributions to chronic lateral ankle instability.
        Sports Med. 2006; 36: 263-277
        • Jones G.M.
        • Watt D.G.
        Muscular control of landing from unexpected falls in man.
        J. Physiol. 1971; 219: 729-737
        • Konradsen L.
        • Voigt M.
        Inversion injury biomechanics in functional ankle instability: a cadaver study of simulated gait.
        Scand. J. Med. Sci. Sports. 2002; 12: 329-336
        • Kristianslund E.
        • Bahr R.
        • Krosshaug T.
        Kinematics and kinetics of an accidental lateral ankle sprain.
        J. Biomech. 2011; 44: 2576-2578
        • McLean S.G.
        The ACL injury enigma: we can't prevent what we don't understand.
        J. Athl. Train. 2008; 43: 538-540
        • McLean S.G.
        • Samorezov J.E.
        Fatigue-induced ACL injury risk stems from a degradation in central control.
        Med. Sci. Sports Exerc. 2009; 41: 1661-1672
        • McVey E.D.
        • Palmieri R.M.
        • Docherty C.L.
        • Zinder S.M.
        • Ingersoll C.D.
        Arthrogenic muscle inhibition in the leg muscles of subjects exhibiting functional ankle instability.
        Foot Ankle Int. 2005; 26: 1055-1061
        • Mok K.M.
        • Fong D.T.
        • Krosshaug T.
        • Engebretsen L.
        • Hung A.S.
        • Yung P.S.
        • et al.
        Kinematics analysis of ankle inversion ligamentous sprain injuries in sports: 2 cases during the 2008 Beijing Olympics.
        Am. J. Sports Med. 2011; 39: 1548-1552
        • O'Connor K.M.
        • Bottum M.C.
        Differences in cutting knee mechanics based on principal components analysis.
        Med. Sci. Sports Exerc. 2009; 41: 867-878
        • Verhagen R.A.
        • de Keizer G.
        • van Dijk C.N.
        Long-term follow-up of inversion trauma of the ankle.
        Arch. Orthop. Trauma Surg. 1995; 114: 92-96
        • Woltring H.J.
        • Huiskes R.
        • de Lange A.
        • Veldpaus F.E.
        Finite centroid and helical axis estimation from noisy landmark measurements in the study of human joint kinematics.
        J. Biomech. 1985; 18: 379-389
        • Wright I.C.
        • Neptune R.R.
        • van den Bogert A.J.
        • Nigg B.M.
        The influence of foot positioning on ankle sprains.
        J. Biomech. 2000; 33: 513-519
        • Yeung M.S.
        • Chan K.M.
        • So C.H.
        • Yuan W.Y.
        An epidemiological survey on ankle sprain.
        Br. J. Sports Med. 1994; 28: 112-116