Changes in clinical symptoms and functional disability in patients with coexisting patellofemoral and tibiofemoral osteoarthritis: a 1-year prospective cohort study

Table 2 Comparison of characteristics between patients with coexisting PFOA and those with isolated TFOA^a

Variables	TFOA + PFOA (n = 45)	Isolated TFOA (n = 27)	P-value^**
Age, years	75.2 ± 8.86	71.6 ± 6.21	0.064
Women, no. (%)	33 (73.3)	20 (74.0)	0.945
Height, meters	1.54 ± 0.08	1.57 ± 0.08	0.120
Weight, kg	59.6 ± 10.2	55.7 ± 10.2	0.125
Body mass index, kg/m2	25.1 ± 3.76	21.7 ± 5.29	0.002
Tibiofemoral joint K/L grade, no. (%)			0.001
Grade 2	23 (51.1)	25 (92.6)
Grade 3	13 (28.9)	1 (3.7)
Grade 4	9 (20.0)	1 (3.7)
Patellofemoral joint K/L grade, no. (%)			–
Grade 0	0 (0)	2 (7.4)
Grade 1	0 (0)	25 (92.6)
Grade 2	30 (66.7)	0 (0)
Grade 3	9 (20.0)	0 (0)
Grade 4	6 (13.3)	0 (0)
Location of patellofemoral osteoarthritis, no. (%)			–
Medial facet	4 (8.9)	–
Lateral facet	18 (40.0)	–
Mixed (medial and lateral) facet	23 (51.1)	–
Patellar alignment and trochlear morphology
Lateral displacement, %	10.4 ± 5.87	5.73 ± 5.01	<0.001
Tilting angle, degrees^b	4.52 ± 4.27	6.95 ± 3.54	0.009
Sulcus angle, degrees	133.6 ± 6.49	134.4 ± 6.89	0.602

TFOA Tibiofemoral osteoarthritis, PFOA Patellofemoral osteoarthritis, K/L grade Kellgren/Lawrence grade
P-values indicating statistically significant differences (<0.05) are displayed in bold
^**Based on unadjusted analysis (Student’s t-test [age, weight, and sulcus angle], Mann-Whitney U test [height, body mass index, lateral displacement, and tilting angle], or chi-square/Fisher's exact tests [sex, tibiofemoral and patellofemoral joint K/L grades, and location of patellofemoral osteoarthritis]) of the TFOA + PFOA and isolated TFOA groups
^aExcept where otherwise indicated, values are mean ± SD
^bA positive value for tilting angle indicates patellar tilt toward the lateral side and a negative value to the medial side

ISSN: 1471-2474