Richard W Willy1, Annelie Brorsson2, Hayley C Powell1, John D Willson1, Roy Tranberg2, Karin Grävare Silbernagel2,3. 1. Department of Physical Therapy, College of Allied Health Sciences, East Carolina University, Greenville, North Carolina, USA. 2. Department of Orthopaedics, Institute of Clinical Sciences at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. 3. Department of Physical Therapy, University of Delaware, Newark, Delaware, USA.
Abstract
BACKGROUND: Deficits in plantarflexor function are common after an Achilles tendon rupture. These deficits may result in an altered distribution of joint loads during lower extremity tasks. HYPOTHESIS: We hypothesized that, regardless of treatment, the Achilles tendon-ruptured limb would exhibit deficits in ankle kinematics and joint power while exhibiting elevated knee joint power and patellofemoral joint loads during walking, jogging, and hopping. We further hypothesized that this loading pattern would be most evident during jogging and hopping. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty-four participants (17 participants treated surgically, 17 treated nonsurgically) were tested at a mean 6.1 ± 2.0 years after an Achilles tendon rupture. Lower extremity kinematics and kinetics were assessed while participants completed walking, jogging, and single-legged hopping trials. Patellofemoral joint stress was calculated via a musculoskeletal model. Data were analyzed via mixed-model repeated analyses of variance (α = .05) and the limb symmetry index (LSI). RESULTS: No differences ( P ≥ .05) were found between the surgical and nonsurgical groups. In both groups, large side-to-side deficits in the plantarflexion angle at toeoff (LSI: 53.5%-73.9%) were noted during walking, jogging, and hopping in the involved limb. Side-to-side deficits in the angular velocity were only present during jogging (LSI: 93.5%) and hopping (LSI: 92.5%). This pattern was accompanied by large deficits in eccentric (LSI: 80.8%-94.7%) and concentric (LSI: 82.2%-84.7%) ankle joint powers in the involved limb during all tasks. Interestingly, only jogging and hopping demonstrated greater knee joint loads when compared with the uninvolved limb. Concentric knee power was greater during jogging (LSI: 117.2%) and hopping (LSI: 115.9%) compared with the uninvolved limb. Similarly, peak patellofemoral joint stress was greater in the involved limb during jogging (LSI: 107.5%) and hopping (LSI: 107.1%), while only hopping had a greater loading rate of patellofemoral joint stress (LSI: 110.9%). CONCLUSION: Considerable side-to-side deficits in plantarflexor function were observed during walking, jogging, and hopping in patients after an Achilles tendon rupture. As a possible compensation, increased knee joint loads were present but only during jogging and hopping. CLINICAL RELEVANCE: These data suggest that after an Achilles tendon rupture, patients may be susceptible to greater mechanical loading of the knee during sporting tasks, regardless of surgical or nonsurgical treatment.
BACKGROUND: Deficits in plantarflexor function are common after an Achilles tendon rupture. These deficits may result in an altered distribution of joint loads during lower extremity tasks. HYPOTHESIS: We hypothesized that, regardless of treatment, the Achilles tendon-ruptured limb would exhibit deficits in ankle kinematics and joint power while exhibiting elevated knee joint power and patellofemoral joint loads during walking, jogging, and hopping. We further hypothesized that this loading pattern would be most evident during jogging and hopping. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty-four participants (17 participants treated surgically, 17 treated nonsurgically) were tested at a mean 6.1 ± 2.0 years after an Achilles tendon rupture. Lower extremity kinematics and kinetics were assessed while participants completed walking, jogging, and single-legged hopping trials. Patellofemoral joint stress was calculated via a musculoskeletal model. Data were analyzed via mixed-model repeated analyses of variance (α = .05) and the limb symmetry index (LSI). RESULTS: No differences ( P ≥ .05) were found between the surgical and nonsurgical groups. In both groups, large side-to-side deficits in the plantarflexion angle at toeoff (LSI: 53.5%-73.9%) were noted during walking, jogging, and hopping in the involved limb. Side-to-side deficits in the angular velocity were only present during jogging (LSI: 93.5%) and hopping (LSI: 92.5%). This pattern was accompanied by large deficits in eccentric (LSI: 80.8%-94.7%) and concentric (LSI: 82.2%-84.7%) ankle joint powers in the involved limb during all tasks. Interestingly, only jogging and hopping demonstrated greater knee joint loads when compared with the uninvolved limb. Concentric knee power was greater during jogging (LSI: 117.2%) and hopping (LSI: 115.9%) compared with the uninvolved limb. Similarly, peak patellofemoral joint stress was greater in the involved limb during jogging (LSI: 107.5%) and hopping (LSI: 107.1%), while only hopping had a greater loading rate of patellofemoral joint stress (LSI: 110.9%). CONCLUSION: Considerable side-to-side deficits in plantarflexor function were observed during walking, jogging, and hopping in patients after an Achilles tendon rupture. As a possible compensation, increased knee joint loads were present but only during jogging and hopping. CLINICAL RELEVANCE: These data suggest that after an Achilles tendon rupture, patients may be susceptible to greater mechanical loading of the knee during sporting tasks, regardless of surgical or nonsurgical treatment.
Authors: Jennifer A Zellers; Ryan T Pohlig; Daniel H Cortes; Karin Grävare Silbernagel Journal: Knee Surg Sports Traumatol Arthrosc Date: 2019-07-02 Impact factor: 4.342
Authors: Daniel Jandacka; Julia Freedman Silvernail; Jaroslav Uchytil; David Zahradnik; Roman Farana; Joseph Hamill Journal: J Foot Ankle Res Date: 2017-11-28 Impact factor: 2.303