Changes in clinical symptoms and functional disability in patients with coexisting patellofemoral and tibiofemoral osteoarthritis: a 1-year prospective cohort study.
This 1-year prospective cohort study aimed to compare the changes in clinical symptoms and functional disability between patients with coexisting patellofemoral (PF) and tibiofemoral (TF) osteoarthritis (OA) and those with isolated TFOA.



Seventy-two patients with medial knee OA were enrolled. Knee pain and functional disability were assessed at baseline and at 1-year follow-up using the Japanese Knee Osteoarthritis Measure (JKOM) and a visual analog scale (VAS). We performed two-way analysis of covariance for the clinical outcome variables to examine, time (baseline and follow-up), group (coexisting PFOA and isolated TFOA), and time-group interaction effects. Furthermore, we conducted post-hoc exploratory analysis to address the possibility that dividing patients according to location of PFOA (i.e., isolated lateral, isolated medial, and mixed [bilateral]) may identify a distinct subgroup with different changes in clinical outcomes at 1-year follow-up.



We detected group effects only in scores of the JKOM pain subscale (P = 0.012) and VAS (P = 0.033), adjusted for age, sex, and body mass index. Patients with coexisting PFOA have stable moderate level knee pain and functional disability throughout the year which is significantly worse than that in those with isolated TFOA. Post-hoc subgroup analysis demonstrated that change of knee pain likely varied with location of PFOA. Patients with isolated lateral PFOA had mild/moderate level knee pain, and their VAS scores were likely to improve, whereas those with mixed PFOA exhibited stable to worsening moderate/severe knee pain.



Although we did not detect differences in changes in clinical symptoms and functional disability between patients with coexisting PFOA and those with isolated TFOA, our findings indicate that patients with coexisting PFOA had worse clinical symptoms and functional disability than those with isolated TFOA. The results of the exploratory analysis suggested that patients with coexisting PFOA might have heterogeneous clinical outcomes, and presence of mixed PFOA might be an indicator of severe clinical knee OA.
Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.|Japan Society for the Promotion of Science, Tokyo, Japan.
Hirotaka
H
Iijima
Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Naoto
N
Fukutani
Rehabilitation Center, Fujioka General Hospital, Gunma, Japan.
Takuya
T
Isho
Nozomi Orthopaedic Clinic, Hiroshima, Japan.
Yuko
Y
Yamamoto
Nozomi Orthopaedic Clinic, Hiroshima, Japan.
Masakazu
M
Hiraoka
Nozomi Orthopaedic Clinic, Hiroshima, Japan.
Kazuyuki
K
Miyanobu
Nozomi Orthopaedic Clinic, Hiroshima, Japan.
Masashi
M
Jinnouchi
Nozomi Orthopaedic Clinic, Hiroshima, Japan.
Eishi
E
Kaneda
Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan. aoyama.tomoki.4e@kyoto-u.ac.jp.
Tomoki
T
Aoyama
Department of Physical Therapy, Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Hiroshi
H
Kuroki
Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Shuichi
S
Matsuda
D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000145:classification / Q000503:physiopathology*; D057071:Patellofemoral Joint / Q000503:physiopathology*; D011446:Prospective Studies
Disability; Knee pain; Patellofemoral osteoarthritis; Tibiofemoral osteoarthritis