Characterizing posterior calcaneal spur fractures in insertional Achilles tendinopathy: A case control study

Table 1 Participant demographics

Parameter	Subclass	n (%)/mean ± SD (median, range)
Sex	Female	59 (26.0)
	Male	168 (74.0)
Age (years)		53.9 ± 12.0 (54, 26-87)
Height (cm)		168.1 ± 8.7 (169, 146-189)
Weight (kg)		77.1 ± 15.7 (75.9, 38.5-147.5)
Body mass index		27.3 ± 5.1 (26.0, 16.4-43.7)
Side	Left	107
	Right	120
Spur fracture	Yes	87 (38.3)
	No	140 (61.7)
Spur length (mm)		8.2 ± 4.8 (7, 1-24)

Table 2 Comparison of demographics between cases with and without spur fractures, mean ± SD (median, range)

Parameter	With spur fracture	Without spur fracture	P value
Total number (female, male)	87 (11, 76)	140 (48, 92)	< 0.001c
Age (years)	51.0 ± 10.5 (50, 32-87)	55.7 ± 12.5 (55, 26-81)	0.004
Height (cm)	171.5 ± 7.5 (172.2, 150-189.2)	166.0 ± 8.7 (168, 146.5-185.3)	< 0.001c
Weight (kg)	80.0 ± 14.5 (78.5, 39.5-147.5)	75.3 ± 16.3 (72.2, 43.5-123.8)	0.016
Body mass index	27.1 ± 4.2 (26.1, 16.4-41.2)	27.4 ± 5.6 (25.8, 19.3-43.7)	0.56
Side (left, right)	87 (39, 48)	140 (68, 72)	0.59
Spur length (mm)	12.3 ± 4.5 (11, 3-24)	5.7± 3.0 (5.5, 1-19)	< 0.001c

^cP < 0.001.

Categorical and continuous variables were analyzed using Fisher’s exact test and the Mann-Whitney U test, respectively. P values were compared against the Bonferroni-adjusted significance threshold of P < 0.002.

Table 3 Comparison of female patients with and without spur fractures, n (%), mean ± SD (median, range)

Parameter	With spur fracture	Without spur fracture	P value
n	11 (18.6)	48 (81.4)
Age (years)	53.2 ± 11.3 (55, 35-69)	56.4 ± 13.4 (54.5, 31-78)	0.612
Height (cm)	161.1 ± 5.7 (161.9, 150-168)	157.0 ± 6.8 (157, 146.5-175)	0.051
Weight (kg)	73.3 ± 15.3 (76.1, 39.5-92.5)	72.1 ± 20.4 (65.5, 43.5-110.8)	0.532
Body mass index	28.3 ± 6.3 (27.9, 16.4-39.4)	29.2 ± 7.0 (26.7, 19.6-43.7)	0.984
Side (left, right)	11 (5, 6)	48 (20, 28)	1.00
Spur length	10.7 ± 4.0 (9, 6-17)	4.8 ± 2.1 (5, 1-10)	< 0.001c

^cP < 0.001.

The Mann-Whitney U test was used. P values were compared against the Bonferroni-adjusted significance threshold of P < 0.002.

Table 4 Comparison of male patients with and without spur fractures, n (%), mean ± SD (median, range)

Parameter	With spur fracture	Without spur fracture	P value
n	76 (45.2)	92 (54.8)
Age (years)	50.8 ± 10.4 (49.5, 32-87)	55.3 ± 12.1 (55.5, 26-81)	0.003
Height (cm)	173.1 ± 6.4 (174, 156-189.2)	171.0 ± 4.9 (170.8, 158-185.3)	0.02
Weight (kg)	81.0 ± 14.2 (79.0, 58.0-147.5)	77.2 ± 13.3 (74.8, 57.7-123.8)	0.06
Body mass index	26.9 ± 3.6 (25.8, 19.9-41.2)	26.5 ± 4.5 (25.4, 19.3-39.8)	0.236
Side (left, right)	76 (34, 42)	92 (48, 44)	0.356
Spur length	12.5 ± 4.6 (11.5, 3-24)	6.2 ± 3.3 (6, 1-19)	< 0.001c

^cP < 0.001.

The Mann-Whitney U test was used. P values were compared against the Bonferroni-adjusted significance threshold of P < 0.002.

Table 5 Comparison of female and male patients with spur fractures, n (%), mean ± SD (median, range)

Parameter	Female	Male	P value
n	11 (18.6)	76 (45.2)
Age (years)	53.2 ± 11.3 (55, 35-69)	50.8 ± 10.4 (49.5, 32-87)	0.467
Height (cm)	161.1 ± 5.7 (161.9, 150-168)	173.1 ± 6.4 (174, 156-189.2)	< 0.001c
Weight (kg)	73.3 ± 15.3 (76.1, 39.5-92.5)	81.0 ± 14.2 (79.0, 58.0-147.5)	0.106
Body mass index	28.3 ± 6.3 (27.9, 16.4-39.4)	26.9 ± 3.6 (25.8, 19.9-41.2)	0.311
Side (left, right)	11 (5, 6)	76 (34, 42)	1.00
Spur length	10.7 ± 4.0 (9, 6-17)	12.5 ± 4.6 (11.5, 3-24)	0.211

^cP < 0.001.

The Mann-Whitney U test was used. P values were compared against the Bonferroni-adjusted significance threshold of P < 0.002.