In the JournalsPerspective

Slow walking speed may be a sign of patellofemoral OA after ACL reconstruction

Jacob J. Capin

According to study results, slower walking speed was a strong predictor of worse trochlear cartilage health. This finding led researchers to conclude that slow walking speed may be an early sign of patellofemoral osteoarthritis after ACL reconstruction.

“We examined the relationship between an early indicator of knee osteoarthritis (femoral trochlear T2 relaxation time) and several biomechanical variables during walking,” study co-author Jacob J. Capin, PT, DPT, PhD, told Healio.com/Orthopedics. “Our key findings were that walking speed was the strongest predictor of early patellofemoral osteoarthritis in the ACL reconstructed limb, and most biomechanical variables were either weakly correlated or not associated with cartilage degradation. While cause and effect cannot be determined from this study, patients who walked faster had healthier knee cartilage.”

Capin and colleagues compared walking mechanics 3 months after ACL reconstruction with femoral trochlear cartilage T2 relaxation times 6 months after ACL reconstruction. After primary unilateral ACL reconstruction, 26 patients participated in detailed motion analyses 3.3 months after ACL reconstruction and underwent quantitative MRI at 6.3 months postoperatively.

Results showed no between limb differences in femoral trochlear cartilage T2 relaxation time. Investigators noted slower walking speed correlated with higher femoral trochlear cartilage T2 relaxation times in the involved limb. Slower walking speed also correlated with greater interlimb differences in trochlear T2 relaxation times. Walking mechanics and trochlear T2 relaxation times were weakly correlated.

Capin said, “As a clinician-scientist, our findings are both somewhat surprising and quite exciting as walking speed may be evaluated accurately within a clinical setting whereas biomechanical variables, such as joint angles and muscle forces, cannot.”– by Monica Jaramillo

 

Disclosures: Capin reports the study was part of his PhD dissertation funded by a Ruth L. Kirschstein National Research Service Award Predoctoral Fellowship (NICHD F30-HD096830) and by the Foundation for Physical Therapy Research Promotion of Doctoral Studies (PODS) Level 1 and Level 2 Scholarships. Please see the study for a list of all other authors’ relevant financial disclosures.

 

Jacob J. Capin

According to study results, slower walking speed was a strong predictor of worse trochlear cartilage health. This finding led researchers to conclude that slow walking speed may be an early sign of patellofemoral osteoarthritis after ACL reconstruction.

“We examined the relationship between an early indicator of knee osteoarthritis (femoral trochlear T2 relaxation time) and several biomechanical variables during walking,” study co-author Jacob J. Capin, PT, DPT, PhD, told Healio.com/Orthopedics. “Our key findings were that walking speed was the strongest predictor of early patellofemoral osteoarthritis in the ACL reconstructed limb, and most biomechanical variables were either weakly correlated or not associated with cartilage degradation. While cause and effect cannot be determined from this study, patients who walked faster had healthier knee cartilage.”

Capin and colleagues compared walking mechanics 3 months after ACL reconstruction with femoral trochlear cartilage T2 relaxation times 6 months after ACL reconstruction. After primary unilateral ACL reconstruction, 26 patients participated in detailed motion analyses 3.3 months after ACL reconstruction and underwent quantitative MRI at 6.3 months postoperatively.

Results showed no between limb differences in femoral trochlear cartilage T2 relaxation time. Investigators noted slower walking speed correlated with higher femoral trochlear cartilage T2 relaxation times in the involved limb. Slower walking speed also correlated with greater interlimb differences in trochlear T2 relaxation times. Walking mechanics and trochlear T2 relaxation times were weakly correlated.

Capin said, “As a clinician-scientist, our findings are both somewhat surprising and quite exciting as walking speed may be evaluated accurately within a clinical setting whereas biomechanical variables, such as joint angles and muscle forces, cannot.”– by Monica Jaramillo

 

Disclosures: Capin reports the study was part of his PhD dissertation funded by a Ruth L. Kirschstein National Research Service Award Predoctoral Fellowship (NICHD F30-HD096830) and by the Foundation for Physical Therapy Research Promotion of Doctoral Studies (PODS) Level 1 and Level 2 Scholarships. Please see the study for a list of all other authors’ relevant financial disclosures.

 

    Perspective
    Andrew J. Cosgarea

    Andrew J. Cosgarea

    In the paper “Slower walking speed is related to early femoral trochlear cartilage degradation after ACL reconstruction,” authors Jacob Capin and colleagues use a novel approach to investigating patellofemoral joint degeneration. With the knowledge that patellofemoral OA is prevalent after ACL reconstruction (ACLR) and using quantitative MRI to characterize chondral precursors to OA, the authors correlated walking gait mechanics 3 months after ACLR with MR evaluation of femoral trochlear cartilage T2 relaxation times 6 months after ACLR.

    They found that slower self-imposed walking speed was the strongest predictor of femoral trochlear cartilage degradation (Pearson r: -.583, P= .002). The authors were careful to point out that they were unable to determine whether slower walking drives cartilage degradation or vice versa, and that multiple graft types were used in the 26 subjects.

    The take-home message is that although this study was only exploratory in nature, information regarding walking speed may be valuable for rehabilitation following injury or surgery and may inform clinicians as to who could be at high risk for subsequently developing patellofemoral OA.

     

    • Andrew J. Cosgarea, MD
    • Drew Family Professor of Orthopedic Surgery in honor of Alec J. Cosgarea
      Department of orthopedic surgery
      Head team physician
      Johns Hopkins University
      Baltimore

    Disclosures: Cosgarea reports no relevant financial disclosures.

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