Comorbidity‐related quality of life in anterior cruciate ligament insufficiency: A cross‐sectional study involving 282 candidates for arthroscopic reconstruction

Figures & data

Table 1.  Variables in the whole study sample and in comorbidity‐stratified subgroups of patients affected by chronic ACL insufficiency with indication for ACL reconstruction

	Whole group	Subgroup A	Subgroup B	P‐value ^a
		(CI = 0)	(CI > 0)
	n = 282	n = 200	n=82
Age, median (range)	28(15–52)	26(15–52)	33(15–51)	< 0.001
Gender, men, n (%)	235 (83)	167 (83)	68 (83)	1.0
women, n (%)	47 (17)	33 (17)	14 (17)
CI, median (range) ^b	0 (0–9)	0 (0–0)	2 (2–9)	< 0.001
IKDC^c, n(%)				1.0
B	134 (48)	95 (48)	39 (48)
C	131 (46)	93 (46)	38 (46)
D	17 (6)	12 (6)	5 (6)
TAT, mean (SD)^d	10 (3)	9 (2)	10 (2)	0.04
SSD, mean (SD)^e	5 (3)	4 (3)	5 (3)	0.04
Meniscal tears, total, n (%)	152 (54)	110 (55)	42 (51)	0.5
medial	94 (62)	68 (62)	26 (62)
lateral	36 (24)	29 (26)	7 (17)
both	22 (14)	13 (12)	9 (21)
Chondral lesions total, n (%)^f	45 (16)	31 (16)	14 (17)	0.6
grade I	8	3	5
grade II	12	10	2
grade III	16	9	7
grade IV	9	9	0
Meniscal plus chondral
lesions, n (%)	33(12)	24(12)	9(11)	1.0

^a Significance of inter‐group (subgroup A vs. subgroup B) comparison of variables (Mann‐Whitney U test and contingency tables).

^b CI: median and (range) values of comorbidity index calculated according to the Self‐administered Comorbidity Questionnaire (SCQ) (Sangha et al., 2003).

^c IKDC: International Knee Documentation Committee evaluation form.

^d TAT: Tibial anterior translation in mm, measured with KT‐1000 arthrometer at maximum manual traction and reported as mean and standard deviation (SD).

^e SSD: side‐to‐side difference in mm, measured with KT‐1000 arthrometer at maximum manual traction and reported as mean and standard deviation (SD).

^f Degree of chondral lesions according to Outerbridge.

Table 2.  Type and frequency of medical conditions in 82 patients with comorbidity associated with ACL insufficiency

Type of medical comorbidity a	No. of patients
Single comorbidity
Back pain ^b	36
High blood pressure ^b	7
Lung disease ^b 5	5
Ulcer or stomach disease ^b 5	5
Anemia or other blood disease ^b 3	3
Liver disease ^b 2	2
Heart disease ^b 2	2
Migraine^c 2	2
Osteoarthritis ^b (post‐traumatic) 1	1
Ulcerative rectocolitis ^c 1	1
Hypothyroidism^c 1	1
Subtotal 65	56
Multiple comorbidities
Back pain ^b plus lung disease ^b 5	5
Back pain ^b plus allergy ^c 1	1
Back pain ^b plus anemia or other blood disease ^b 1	1
Back pain ^b plus ulcer or stomach disease ^b 1	1
Back pain ^b plus depression ^b 1	1
Back pain ^b plus rotator cuff disease ^c 1	1
Back pain ^b plus anemia or other blood disease ^b plus kidney disease ^b	1
Back pain ^b plus high blood pressurea plus lung disease ^b	1
Lung disease ^b plus heart disease ^b 1	1
Lung disease ^b plus liver disease ^b 1	1
Lung disease ^b plus ulcer or stomach disease ^b 1	1
High blood pressure ^b plus ulcer or	1
stomach disease ^b 1	1
Depression ^b plus sinusitis ^c 1	1
Subtotal 17	17
Total	82/82

^a The type of comorbidity is reported using terminology of the self‐administered comorbidity questionnaire (SCQ) (Sangha et al. 2003). The SCQ lists thirteen defined medical conditions (closed‐ended items: heart disease; high blood pressure; lung disease; diabetes; ulcer or stomach disease; kidney disease; liver disease; anemia or other blood disease; cancer; depression; osteoarthritis, degenerative arthritis; back pain; rheumatoid arthritis) and three medical diseases (openended items) that may be added by the patient. The SCQ requires that the diagnosis of the patient's self‐reported comorbidity has been made by a physician.

^b closed‐ended item.

^c open‐ended item.

Table 3.  SF‐36 domain scores in the whole study sample and in comorbidity‐stratified subgroups of patients affected by chronic ACL insufficiency with indication for ACL reconstruction

	Total				SF‐36 domain ^a
	n	PF	RP	BP	GH	VT	SF	RE	MH
Whole group	282
Mean (SD)		84 (15)	59 (39)	75 (23)	78 (13)	68 (16)	77 (22)	79 (33)	75 (16)
NBS ^b, mean		−11	−30	−9	+2	−1	−6	−5	+1
95% CL ^c		−13;−9	−34; −25	−12;−6	−0.1;+3	−3;+1	−9;−4	−9;−1	−0.6;+3
Subgroup A	200
(CI = 0)
Mean (SD)		86 (13)	61 (38)	77 (23)	80 (12)	70 (16)	78 (22)	80 (12)	77 (15)
NBS ^b, mean		−10	−28	−7	+4	+0.5	.5	+4	+2
95% CL ^c		−11;−8	−33; −22	−10;−4	+2;+5	−2;+3	−8;−2	−8; +0.6	+0.4;+5
Subgroup B	82
(CI > 0)
Mean (SD)		80 (17)	55 (40)	68 (21)	72(15)	64 (16)	74 (23)	75 (36)	74 (23)
NBS ^b, mean		−15	−34	−14	−3	34	−9	−9	−2
95% CL ^c		−19;−11	−42; −25	−19;−9	−6;+0.3	−8; −0.8	−14;−4	−17;−0.7	−6;+2

^a PF: physical functioning; RP: role physical (role limitations due to physical health problems); BP: bodily pain; GH: general health; VT: vitality; SF: social functioning; RE: role emotional (role limitations due to emotional health problems); MH: mental health.

^b NBS: norm‐based scoring obtained by comparison with the Italian norm (Apolone et al. 1997). The age‐ and gender‐matched SF‐36 domain scores are expressed as difference from the mean equalling zero, with positive and negative values indicating higher and lower scores, respectively, than the norm.

^c CL: confidence limits; confidence intervals not including zero indicate statistical significance.

The mean differences in SF‐36 domain scores in subgroup A (n = 200, CI = 0) and in subgroup B (n = 82, CI > 0) from the age‐ and sex‐adjusted Italian norm (Apolone et al. 1997). SF‐36 domains scoring above or below the reference line represent scores that are higher or lower than the norm, respectively (see for confidence limits and Discussion for the minimum clinically important difference attributable to statistically significant deviations from the norm). Domain legends: PF, Physical Functioning; RP, Role Physical (role limitations due to physical health problems); BP, Bodily Pain; GH, General Health; VT, Vitality; SF, Social Functioning; RE, Role Emotional (role limitations due to emotional health problems); MH, Mental Health.