Precise arthroscopic mini-trochleoplasty combined with medial patellofemoral ligament reconstruction yields comparable complications to isolated medial patellofemoral ligament reconstruction

Table 1 Patient demographics, n (%)/mean ± SD

	PAM + MPFLR group (n = 30)	MPFLR group (n = 20)	P value	PAM + MPFLR cases with type B TD (n = 14)	MPFLR cases with type B TD (n = 10)	P value
Age (year)	25.47 ± 8.27	24.25 ± 7.28	0.5961	25.36 ± 8.39	28.30 ± 7.30	0.3821
Sex (male/female) (n)	6/24	7/13	0.2362	2/12	5/5	0.0853
Side (L/R) (n)	17/13	9/11	0.4192	10/4	5/5	0.2852
Follow-up (month)	27.27 ± 5.19	27.55 ± 4.47	0.8431	27.64 ± 6.67	27.40 ± 4.38	0.9211
Dejour type			0.0003
Normal	0 (0)	0 (0)
Type A	0 (0)	8 (40.0)
Type B	14 (46.7)	10 (50.0)
Type C	3 (10.0)	1 (5.0)
Type D	13 (43.3)	1 (5.0)

¹Mann-Whitney U test.

²Pearson’s χ² test.

³Fisher’s exact test.

PAM: Precise arthroscopic mini-trochleoplasty; MPFLR: Medial patellofemoral ligament reconstruction; TD: Trochlear dysplasia.

Table 2 Comparison of patient-reported outcome measure scores between the precise arthroscopic mini-trochleoplasty + medial patellofemoral ligament reconstruction and medial patellofemoral ligament reconstruction groups and subgroups with type B trochlear dysplasia

	PAM + MPFLR group (n = 30)	MPFLR group (n = 20)	P value1	PAM + MPFLR cases with type B TD (n = 14)	MPFLR cases with type B TD (n = 10)	P value1
VAS score
Preoperative	1.73 ± 1.48	5.45 ± 2.67	0.000	1.71 ± 1.27	5.00 ± 2.63	0.000
Postoperative	1.03 ± 0.85	0.95 ± 0.83	0.733	1.21 ± 0.89	0.80 ± 0.92	0.280
P value1	0.029	0.000		0.238	0.000
IKDC score
Preoperative	58.93 ± 22.71	57.64 ± 16.60	0.829	56.32 ± 24.01	54.14 ± 7.05	0.784
Postoperative	77.28 ± 9.58	87.13 ± 6.07	0.000	77.83 ± 7.62	86.44 ± 5.33	0.006
P value1	0.000	0.000		0.004	0.000
KOOS score
Pain
Preoperative	80.09 ± 15.56	65.83 ± 14.19	0.002	78.57 ± 16.43	64.72 ± 13.74	0.041
Postoperative	90.83 ± 6.93	92.64 ± 3.85	0.295	90.67 ± 6.94	93.06 ± 3.98	0.341
P value1	0.001	0.000		0.017	0.000
Symptoms
Preoperative	68.93 ± 20.29	67.86 ± 19.15	0.852	72.70 ± 18.46	70.71 ± 15.13	0.782
Postoperative	87.50 ± 9.37	87.32 ± 7.81	0.944	89.80 ± 7.66	84.64 ± 8.26	0.130
P value1	0.000	0.000		0.004	0.020
ADL
Preoperative	74.02 ± 21.90	67.06 ± 20.16	0.262	72.90 ± 22.53	68.68 ± 15.76	0.616
Postoperative	90.88 ± 6.69	92.35 ± 2.68	0.356	91.60 ± 7.15	91.62 ± 2.20	0.992
P value1	0.000	0.000		0.006	0.000
Sport/Rec
Preoperative	61.33 ± 27.70	53.75 ± 21.51	0.307	58.57 ± 26.71	54.50 ± 18.17	0.681
Postoperative	77.33 ± 17.06	86.00 ± 5.28	0.033	78.57 ± 17.91	86.50 ± 4.74	0.188
P value1	0.013	0.000		0.028	0.000
QOL
Preoperative	55.42 ± 21.88	55.94 ± 21.41	0.934	54.02 ± 24.95	58.13 ± 9.79	0.628
Postoperative	80.42 ± 8.00	82.50 ± 6.60	0.339	80.80 ± 5.73	81.25 ± 7.80	0.873
P value1	0.000	0.000		0.001	0.000
Lysholm score
Preoperative	51.40 ± 27.49	48.95 ± 7.84	0.700	49.29 ± 28.71	48.80 ± 8.00	0.959
Postoperative	87.73 ± 9.46	89.65 ± 3.39	0.390	87.00 ± 7.76	88.40 ± 2.88	0.593
P value1	0.000	0.000		0.000	0.000
Tegner activity score
Preoperative	2.87 ± 1.96	1.90 ± 1.25	0.057	2.71 ± 1.86	1.60 ± 1.07	0.104
Postoperative	5.03 ± 1.54	5.95 ± 1.10	0.026	4.93 ± 1.49	5.90 ± 1.20	0.103
P value1	0.000	0.000		0.002	0.000

¹Mann-Whitney U test.

Data are expressed as n or mean ± SD unless otherwise indicated. PAM: Precise arthroscopic mini-trochleoplasty; MPFLR: Medial patellofemoral ligament reconstruction; TD: Trochlear dysplasia; VAS: Visual analog scale; IKDC: International Knee Documentation Committee; KOOS: Knee Injury and Osteoarthritis Outcome Score; ADL: Activities of daily living; QOL: Quality of life.

Table 3 Comparison of patellar instability risk factors between the two groups

	PAM + MPFLR group (n = 30)	MPFLR group (n = 20)	P value1
TT-TG distance (mm; threshold: 16.4 mm[26])
Preoperative	18.30 ± 2.86	15.47 ± 3.24	0.002
Postoperative	13.90 ± 2.32	14.59 ± 2.22	0.306
P value1	0.000	0.324
LTI (°; threshold: 16.2°[26])
Preoperative	-4.91 ± 11.00	10.52 ± 7.07	0.000
Postoperative	15.67 ± 9.81	10.98 ± 6.96	0.071
P value1	0.000	0.839
LPT (°; threshold: 17.2°[26])
Preoperative	29.33 ± 9.05	26.05 ± 7.12	0.179
Postoperative	11.58 ± 8.13	14.13 ± 6.87	0.254
P value1	0.000	0.000

¹Mann-Whitney U test.

Data are expressed as n or mean ± SD unless otherwise indicated. PAM: Precise arthroscopic mini-trochleoplasty; MPFLR: Medial patellofemoral ligament reconstruction; LTI: Lateral trochlear inclination; TT-TG: Tibial tubercle-trochlear groove; LPT: Lateral patellar tilt.

Table 4 Comparison of postoperative complications and clinical data between the precise arthroscopic mini-trochleoplasty + medial patellofemoral ligament reconstruction and medial patellofemoral ligament reconstruction groups, n (%)

	PAM + MPFLR group (n = 30)	MPFLR group (n = 20)	P value1	PAM + MPFLR cases with type B TD (n = 14)	MPFLR cases with type B TD (n = 10)	P value1
Redislocation	1 (3.3)	0 (0)	1.000	0 (0)	0 (0)	1.000
Postoperative subluxation	0 (0)	0 (0)	1.000	0 (0)	0 (0)	1.000
Apprehension sign	2 (6.7)	5 (25.0)	0.100	1 (7.1)	4 (40.0)	0.075
Residual instability	3 (10.0)	5 (25.0)	0.240	1 (7.1)	4 (40.0)	0.075
Reduced range of motion	1 (3.3)	0 (0)	1.000	1 (7.1)	0 (0)	1.000
Reoperation	1 (3.3)	0 (0)	1.000	1 (7.1)	0 (0)	1.000
Increased pain	2 (6.7)	1 (5.0)	1.000	0 (0)	0 (0)	1.000
Stiffness	0 (0)	0 (0)	1.000	0 (0)	0 (0)	1.000
Infection	0 (0)	0 (0)	1.000	0 (0)	0 (0)	1.000
Deep vein thrombosis	1 (3.3)	0 (0)	1.000	0 (0)	0 (0)	1.000

¹Fisher’s exact test.

PAM: Precise arthroscopic mini-trochleoplasty; MPFLR: Medial patellofemoral ligament reconstruction; TD: Trochlear dysplasia.