Return to Sports and Minimum 2-Year Outcomes of Bilateral Hip Arthroscopy in High-Level Athletes With a Propensity-Matched Benchmarking Against a Unilateral Control Group

Abstract

Background:

Return to sports (RTS) and patient-reported outcomes (PROs) for high-level athletes after bilateral hip arthroscopy have not been well established.

Purpose:

(1) To report minimum 2-year PROs and RTS rates in high-level athletes who underwent staged bilateral primary hip arthroscopies and (2) to compare clinical results against a propensity-matched control group of high-level athletes who underwent unilateral primary hip arthroscopy.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Data were prospectively collected and retrospectively reviewed for high-level athletes (professional, college, or high school) who underwent staged bilateral hip arthroscopy for femoroacetabular impingement syndrome between September 2009 and October 2018. Inclusion criteria were preoperative and minimum 2-year follow-up for modified Harris Hip Score, Non-arthritic Hip Score, Hip Outcome Score–Sports Specific Subscale (HOS-SSS), and visual analog scale for pain. Exclusion criteria were Tönnis grade >1, hip dysplasia (lateral center-edge angle <18°), and previous ipsilateral hip surgery/conditions. Rates of achieving the minimal clinically important difference (MCID), patient acceptable symptomatic state (PASS), and maximum outcome improvement satisfaction threshold were recorded in addition to RTS. These athletes were then propensity matched in a 1:3 ratio to high-level athletes who underwent unilateral arthroscopy for comparison. Outcomes were compared among the first hip of the study group, the second hip of the study group, and the control group.

Results:

A total of 74 high-level athletes who underwent bilateral hip arthroscopy met the inclusion criteria, and follow-up was available for 68 (91.9%) at 58.9 ± 24.5 months (mean ± SD). Athletes undergoing bilateral hip arthroscopy returned to sports at a high rate (81.7%), demonstrated significant improvements in all recorded PROs, and achieved the MCID and PASS for the HOS-SSS at rates of 80.9% and 64.7%, respectively. PROs, RTS rate, and rates of achieving the MCID and PASS for the HOS-SSS were similar when the bilateral study group was compared with the unilateral control group (P > .05).

Conclusion:

High-level athletes who undergo staged bilateral primary hip arthroscopy for femoroacetabular impingement syndrome may expect favorable PROs and RTS rates at minimum 2-year follow-up. These results were comparable with those of a propensity-matched control group of high-level athletes who underwent unilateral primary hip arthroscopy.

Keywords

athletes return to sports hip arthroscopy bilateral femoroacetabular impingement

Femoroacetabular impingement syndrome (FAIS) and labral tears are commonly encountered in the high-level athlete population and are particularly common in athletes in cutting sports.^{2,13,28,35,42,43,57} It has been proposed that the high rate of FAIS in athletes is associated with bone formation (resulting in cam-type morphology) as a protective mechanism in response to the repetitive high-impact activities often performed by athletes.⁶³

In the general population, bilateral FAIS has been well studied, and the prevalence of contralateral symptomatic FAIS is high, ranging from 15% to 40% in patients undergoing hip arthroscopy.^36,37,47,57 Nawabi et al⁵⁷ reported that in high-level athletes undergoing hip arthroscopy, 28.4% underwent bilateral surgical procedures. The literature has demonstrated good outcomes and high rates of return to sports (RTS) in competitive athletes undergoing hip arthroscopy; however, these studies typically have reported outcomes after unilateral surgery.^{4,5,13,21,45,61}

Only a few studies have evaluated RTS in high-level athletes undergoing bilateral hip arthroscopy or compared RTS rates with those of a propensity-matched control group of patients undergoing unilateral hip arthroscopy.^27,37,60 Rosinksy et al⁶⁰ reported minimum 1-year patient-reported outcomes (PROs) on 82 high-level athletes undergoing bilateral hip arthroscopy and showed favorable outcomes and RTS rates; however, no control group was presented for comparison. Given the high rates of high-level athletes undergoing bilateral hip arthroscopy, establishing minimum 2-year outcomes and RTS rates in this population is important and may help clinicians preoperatively counsel these patients.

The purpose of this study was (1) to report minimum 2-year PROs and RTS rates in high-level athletes who underwent staged bilateral primary hip arthroscopies and (2) to compare clinical results with those of a propensity-matched control group of high-level athletes who underwent unilateral primary hip arthroscopy. It was hypothesized that (1) athletes who underwent bilateral hip arthroscopy would demonstrate significant improvement in all PROs and RTS rates at minimum 2-year follow-up and (2) clinical results in this group would be similar to those of a propensity-matched control group of athletes who underwent unilateral hip arthroscopy.

Methods

Participation in the American Hip Institute Hip Preservation Registry

All patients in this study participated in the American Hip Institute Hip Preservation Registry. Although the present study represents a unique analysis, data on some patients may have been published in other studies. All data collection and reporting received institutional review board approval, and no funding was received for this study.

Patient Selection

Data were prospectively collected and retrospectively reviewed for all patients who underwent hip arthroscopy by the senior surgeon (B.G.D.) between September 2009 and October 2018. Patients were considered eligible if they underwent staged bilateral hip arthroscopy for FAIS during the study period and were high-level athletes (high school, collegiate, or professional) within a year before their first surgical procedure.³² Patients were included in the present analysis if they had preoperative and minimum 2-year follow-up PRO scores for the modified Harris Hip Score (mHHS),⁷ Non-arthritic Hip Score (NAHS),¹⁸ Hip Outcome Score–Sports Specific Subscale (HOS-SSS),⁵⁶ and visual analog scale (VAS) for pain¹⁷ and completed an RTS survey. Follow-up was considered complete if patients had all PRO measures and RTS data or if secondary ipsilateral hip surgery was recorded, such as revision arthroscopy or conversion to total hip arthroplasty. Patients were excluded from the analysis if they had a Tönnis grade of osteoarthritis >1, hip dysplasia (lateral center-edge angle <18°),⁵² previous ipsilateral hip surgery, or previous hip conditions (ie, avascular necrosis, ankylosing spondylitis, Ehlers-Danlos syndrome, Legg-Calvè-Perthes disease, pigmented villonodular synovitis, or slipped capital femoral epiphysis). None of the bilateral operations were same-day procedures. Analysis was performed against a propensity-matched control group of high-level athletes who underwent unilateral hip arthroscopy.

Preoperative Evaluation and Surgical Indications

A detailed patient history, physical examination, and radiographic analysis were collectively utilized preoperatively by the senior author (B.G.D.) to evaluate surgical candidates. Descriptive variables were collected, such as age at surgery, body mass index (BMI), sex, operative side, and follow-up time. Gait, range of motion, strength, points of tenderness, and signs of FAIS or mechanical symptoms (snapping, catching, locking) were noted during physical examination. Radiographs were obtained and evaluated for signs of cam- and pincer-type morphologies, acetabular dysplasia, and osteoarthritis in all patients via the anteroposterior pelvis, Dunn 45°, and false-profile views.²⁰ Radiographic measurements included lateral center-edge angle,⁵⁸ anterior center-edge angle,⁴⁴ alpha angle,¹⁰ Tönnis angle of acetabular inclination,³⁴ and femoral head-neck offset.³⁰ Osteoarthritis was graded according to the Tönnis classification.²³ Cam morphology was defined as an alpha angle >55° or femoral head-neck offset <0.8 cm.^22,30,54 Evaluations of these images were performed using General Electric Healthcare’s Picture Archiving and Communication System. The institution’s radiographic measurements have demonstrated good interobserver reliability in previously published studies.^24,48

Magnetic resonance arthrography was used to identify intra-articular pathology, such as labral tears or chondral damage. Before being recommended for surgery by the senior author (B.G.D.), all patients had pain that interfered with activities of daily living for ≥3 months and failed to improve with activity modification, nonsteroidal anti-inflammatory drugs, physical therapy, intra-articular ultrasound-guided injections, and rest.

Surgical Technique

All arthroscopic procedures were performed by the senior author (B.G.D.). Under general anesthesia, patients were placed in the modified supine position, and traction was applied to a hip.⁴¹ After the anterolateral and midanterior portals were created,⁵³ a systematic diagnostic arthroscopy was performed to assess the labrum, intra-articular cartilage, and ligamentum teres. We documented labral damage using the Seldes classification⁶² and articular cartilage damage and cartilage lesions using the acetabular labrum articular disruption and Outerbridge classifications, respectively.³³ Ligamentum teres damage was graded using the Domb and Villar classifications.⁴⁹

Under fluoroscopic guidance, acetabuloplasty and femoral osteoplasty were performed to address pincer- and cam-type morphologies, respectively, when needed.⁴⁰ When possible, labral tears were repaired via either a base refixation technique or a controlled-tension anatomic loop stitch.²⁵ Irreparable labral tears were treated via labral reconstruction or selective debridement.^25,51 At the end of each procedure, repair or plication of the interportal capsulotomy was performed unless excessive stiffness, adhesive capsulitis, or insufficient capsular tissue was noted.²⁶

Rehabilitation Protocol

After surgery, all patients used crutches with a 20-lb (9 kg) weightbearing restriction and were placed in a DonJoy hip brace (DJO Global) locked at 90° of flexion and 0° of extension for 2 weeks. On postoperative day 1, patients began daily use of a continuous passive motion machine or stationary bicycle. All patients received the institution’s rehabilitation protocol, with a predetermined goal of RTS 6 months after their second surgical procedure. The rehabilitation protocol was tailored to the specific procedures performed such that when labral reconstruction or microfracture was performed, the protocol was modified so that the patient was limited to 20-lb (9 kg) weightbearing for 6 to 8 weeks.

RTS and Surgical Outcome Tools

Before their first surgical procedure, all athletes completed a questionnaire reporting the level of participation in sports within 1 year of the surgical date and the sport type. For the bilateral group, RTS was determined after contralateral hip surgery. RTS was defined as a patient’s return to competitive participation in his or her sport.

To establish baseline scores, patients completed the following preoperative questionnaires within a month of the surgery date: mHHS, NAHS, HOS-SSS, VAS for pain, International Hip Outcome Tool (iHOT-12),⁵⁵ 12-Item Short Form Health Survey (SF-12) Physical and Mental,⁶⁴ Veterans RAND 12-Item Health Survey (VR-12) Physical and Mental,³⁹ and satisfaction. Baseline scores for iHOT-12, SF-12 Physical and SF-12 Mental, and VR-12 Physical and VR-12 Mental were not reported, as these PRO measures were added to the institution’s questionnaires well into the study period. Postoperatively, patients completed questionnaires at 3 months, 1 year, and annually thereafter. Secondary ipsilateral hip surgery was also documented for all patients. Outcomes were recorded at clinical visits, via encrypted email, or via telephone interviews.

The rates of patients achieving the minimal clinically important difference (MCID) for the mHHS and HOS-SSS were recorded (8 and 6 points, respectively).¹⁴ Additionally, the number of patients who met the patient acceptable symptomatic state (PASS) for the mHHS and HOS-SSS was documented (74 and 75 points, respectively).¹⁴ The maximum outcome improvement score was also calculated for each patient using the following equation¹¹:

[(outcome score at most recent follow-up – preoperative outcome score) / (maximum possible outcome score – preoperative outcome score)] × 100%.

The rate of patients achieving the maximum outcome improvement satisfaction threshold (MOIST) for the mHHS (54.8%) was recorded as described by Maldonado et al.⁵⁰

Statistical Analysis

Descriptive statistics for continuous variables were reported as means, standard deviations, and ranges. Categorical variables were reported as totals and percentages. Chi-square and Fisher exact tests were used to compare categorical data. Continuous variables were assessed for normality using the Shapiro-Wilk test and assessed for equal variance using the F test. A 2-tailed t test was used to assess normally distributed data sets with equal variance, and a Wilcoxon signed rank test, Mann-Whitney U test, or Welch test was used to analyze nonparametric data. One-way analysis of variance (ANOVA) with a subsequent post hoc Tukey honestly significant difference test was also utilized to assess data for each bilateral procedure and the unilateral cohort. The nonparametric Kruskal-Wallis test was used for samples that violated normality. Statistical analysis was performed using Microsoft Excel with the Real Statistics Add-in (Microsoft Corporation) and RStudio Desktop (Version 1.3.959; RStudio). The threshold for statistical significance was set at P < .05.

Propensity Score Matching

Propensity score matching was utilized to minimize the potential effect of confounding factors. Matching was completed using RStudio. Greedy matching without replacement was used to match athletes with bilateral hip arthroscopy to athletes with unilateral hip arthroscopy in a 1:3 ratio. For this process of matching, a hip in the unilateral group could be matched to a hip in the bilateral group only once. Previous studies have shown that the optimal method for group comparison is greedy matching without replacement.^3,8,9 The groups were matched according to age at the time of surgery, sex, BMI, Tönnis grade, follow-up time, and competition level. An a priori power analysis was calculated to find the number of patients necessary in each group to detect 80% power with a 1:3 matching ratio. Based on an expected mean difference in the mHHS of 8 points, the power analysis determined that 43 athletes in the bilateral group and 129 athletes in the unilateral group would be required.

Results

Patient Characteristics

A total of 74 athletes who underwent bilateral hip arthroscopy met the inclusion criteria. Of those athletes, 68 (136 hips, 91.9%) had minimum 2-year follow-up and information regarding RTS. All 68 bilateral group athletes were successfully matched to 204 (204 hips) athletes who underwent unilateral hip arthroscopy and had minimum 2-year follow-up. The patient selection process is depicted in Figure 1.

The bilateral athlete cohort comprised 44 (64.7%) female and 24 (35.3%) male patients. At the time of the first surgical procedure, the bilateral cohort had a mean age of 19.9 ± 6.7 years, BMI of 23.9 ± 5.5, and follow-up of 62.5 ± 23.4 months. The average time between procedures for the bilateral cohort was 7.8 ± 11.6 months. At the time of the second procedure, the bilateral cohort had a mean age of 20.5 ± 6.8 years, BMI of 23.9 ± 4.8, and follow-up of 58.9 ± 24.5 months. Overall, 44 (64.7%) high school, 17 (25.0%) collegiate, and 7 (10.3%) professional athletes underwent bilateral hip arthroscopy. The unilateral athlete cohort included 126 (61.8%) female and 78 (38.2%) male patients with a mean age of 20.0 ± 6.0 years, BMI of 24.2 ± 4.7, and follow-up of 60.3 ± 32.1 months. There were 125 (61.3%) high school, 57 (27.9%) collegiate, and 22 (10.8%) professional athletes who underwent unilateral hip arthroscopy. The most common sport reported by bilateral and unilateral cohorts was track/running (25% and 21%, respectively) (Figure 2). There were no significant differences in characteristics between the bilateral cohort at the time of the first or second procedure and the unilateral cohort (P > .05). Table 1 presents a full summary of patient characteristics.

Table 1

Patient Characteristics^a

	Bilateral (n = 68)
	First Side	Second Side	Unilateral (n = 204)	P Value
Hips included in study				.104
Left	28 (41.2)	40 (58.8)	96 (47.1)
Right	40 (58.8)	28 (41.2)	108 (52.9)
Sex				.664
Female	44 (64.7)		126 (61.8)
Male	24 (35.3)		78 (38.2)
Age at surgery, y	19.9 ± 6.7 (13.2-44.2)	20.5 ± 6.8 (14.6-44.3)	20.0 ± 6.0 (13.2-58.4)	.784
Body mass index	23.9 ± 5.5 (16.3-48.9)	23.9 ± 4.8 (16.3-42.9)	24.2 ± 4.7 (16.5-44.5)	.836
Time between procedures, mo	7.8 ± 11.6 (1.1-56.1)			—
Follow-up time, mo	62.5 ± 23.4 (24.0-125.2)	58.9 ± 24.5 (24.0-126.1)	60.3 ± 32.1 (24.0-144.0)	.760
Competition level				.874
High school	44 (64.7)		125 (61.3)
College	17 (25.0)		57 (27.9)
Professional	7 (10.3)		22 (10.8)

Values are presented as mean ± SD (range) or n (%). Blanks correspond to repeated data points within the bilateral cohort and P value calculation for time between procedures is not applicable.

Intraoperative Findings and Arthroscopic Procedures

Intraoperative data demonstrated no difference in labral tear type, acetabular or femoral head cartilage damage, or ligamentum teres injuries between the bilateral cohort at the time of the first or second procedure and the unilateral cohort (P > .05). The surgical procedures performed were also similar between groups (P > .05). Intraoperative findings and arthroscopic procedures are presented in Tables 2 and 3, respectively.

Table 2

Intraoperative Findings^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
Seldes: labral tear type				.594
No tear	1 (1.5)	1 (1.5)	4 (2.0)
I	32 (47.1)	35 (51.5)	79 (38.7)
II	19 (27.9)	19 (27.9)	62 (30.4)
I and II	16 (23.5)	13 (19.1)	59 (28.9)
ALAD				.502
0	12 (17.6)	15 (22.1)	31 (15.2)
1	32 (47.1)	27 (39.7)	103 (50.5)
2	17 (25.0)	18 (26.5)	36 (17.6)
3	7 (10.3)	8 (11.8)	31 (15.2)
4	00 (0.0)	00 (0.0)	3 (1.5)
Outerbridge: acetabulum				.285
0	11 (16.2)	16 (23.5)	29 (14.2)
1	33 (48.5)	27 (39.7)	103 (50.5)
2	15 (22.1)	17 (25.0)	38 (18.6)
3	6 (8.8)	5 (7.4)	30 (14.7)
4	3 (4.4)	3 (4.4)	4 (2.0)
Outerbridge: femoral head				.543
0	63 (92.6)	66 (97.1)	191 (93.6)
1	1 (1.5)	1 (1.5)	1 (0.5)
2	1 (1.5)	1 (1.5)	7 (3.4)
3	2 (2.9)	00 (0.0)	3 (1.5)
4	1 (1.5)	00 (0.0)	2 (1.0)
LT percentile class: Domb				.909
0	45 (66.2)	45 (66.2)	142 (69.6)
>0 to <50	14 (20.6)	17 (25.0)	37 (18.1)
50 to <100	8 (11.8)	5 (7.4)	22 (10.8)
100	1 (1.5)	1 (1.5)	3 (1.5)
LT Villar class				.710
No tear	45 (66.2)	45 (66.2)	143 (70.1)
Complete tear	1 (1.5)	1 (1.5)	2 (1.0)
Partial tear	21 (30.9)	21 (30.9)	50 (24.5)
Degenerative tear	1 (1.5)	1 (1.5)	9 (4.4)

Values are presented as n (%). ALAD, acetabular labrum articular disruption; LT, ligamentum teres.

Table 3

Surgical Procedures^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
Labral treatment				.723
None	1 (1.5)	00 (0.0)	2 (1.0)
Debridement	4 (5.9)	6 (8.8)	22 (10.8)
Repair	63 (92.6)	59 (86.8)	173 (84.8)
Reconstruction	00 (0.0)	3 (4.4)	7 (3.4)
Capsular treatment				.061
Repair/plication	53 (77.9)	62 (91.2)	161 (78.9)
Capsulotomy without repair	15 (22.1)	6 (8.8)	43 (21.1)
Acetabuloplasty	55 (80.9)	59 (86.8)	161 (78.9)	.363
Femoroplasty	58 (85.3)	59 (86.8)	171 (83.8)	.834
LT debridement	12 (17.6)	9 (13.2)	37 (18.1)	.642

Values are presented as n (%). LT, ligamentum teres.

Radiographic Findings

There were no significant differences between groups in any pre- or postoperative radiographic measurement. Additionally, there were significant pre- to postoperative changes for lateral center-edge angle, alpha angle, and femoral offset for the unilateral cohort and the bilateral cohort’s first- and second-side procedures (P < .001). Radiographic findings are presented in Table 4.

Table 4

Radiographic Findings^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
Tönnis grade				.913
0	60 (88.2)	60 (88.2)	183 (89.7)
1	8 (11.8)	8 (11.8)	21 (10.3)
LCEA, deg
Preoperative	30.7 ± 5.3 (18-40)	31.8 ± 5.2 (19-48)	30.6 ± 5.8 (18-47)	.123
Latest	29.0 ± 5.5 (20-41)	31.2 ± 14.2 (18-48)	30.4 ± 5.4 (19-43)	.105
P value	<.001	<.001	<.001
ACEA, deg
Preoperative	31.6 ± 6.7 (17-47)	32.1 ± 6.8 (13-47)	31.5 ± 6.9 (18-55)	.312
Latest	30.8 ± 7.4 (9-48)	30.3 ± 8.0 (13-55)	30.1 ± 6.6 (16-46)	.094
P value	.734	.469	.379
Alpha angle, deg
Preoperative	58.5 ± 12.2 (37-99)	57.2 ± 12.0 (39-87)	60.0 ± 13.1 (37-93)	.297
Latest	42.9 ± 6.0 (34-70)	43.2 ± 8.1 (33-83)	45.0 ± 7.8 (32-83)	.072
P value	<.001	<.001	<.001
Tönnis angle, deg
Preoperative	3.1 ± 5.7 (-15-14)	3.8 ± 3.9 (-8-14)	4.1 ± 4.6 (-20-15)	.858
Latest	5.5 ± 3.4 (1-15)	4.3 ± 3.0 (1-15)	5.5 ± 3.9 (0.4-19)	.773
P value	.242	.725	.214
Femoral offset, cm
Preoperative	0.5 ± 0.3 (0.0-1.2)	0.5 ± 0.3 (0.0-0.95)	0.5 ± 0.3 (0.0-1.1)	.865
Latest	0.9 ± 0.2 (0.2-1.2)	0.9 ± 0.2 (0.4-1.2)	0.9 ± 0.2 (0.2-1.4)	.999
P value	<.001	<.001	<.001

Values are presented as mean ± SD (range) or n (%). Bold indicates P < .05. ACEA, anterior center-edge angle; LCEA, lateral center-edge angle.

RTS and PROs

All athletes in the present study experienced significant improvements in the mHHS, NAHS, HOS-SSS, and VAS from preoperative to latest postoperative follow-up (P < .001). The bilateral cohort demonstrated a significant difference in preoperative VAS between the first and second procedures (P = .005). However, there were no other significant differences in any pre- or postoperative score for the mHHS, NAHS, HOS-SSS, or VAS (P > .05). Additionally, no significant differences were found regarding the iHOT-12, SF-12 Physical, SF-12 Mental, VR-12 Physical, and VR-12 Mental at latest follow-up (P > .05). Mean satisfaction scores for patients’ first and second surgical sides were 8.4 and 8.7, respectively, and 8.4 for patients in the unilateral cohort. Additionally, there were no significant differences in the rates of achieving the MCID, PASS, or MOIST between the bilateral and unilateral cohorts (P > .05). A full summary of PROs is presented in Tables 5 and 6.

Table 5

Patient-Reported Outcomes^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
mHHS
Preoperative	64.9 ± 12.9 (37.0 to 96.0)	70.0 ± 15.1 (43.0 to 97.0)	65.5 ± 14.1 (19.0 to 100.0)	.053
Latest	85.4 ± 16.9 (28.0 to 100.0)	90.0 ± 11.7 (58.0 to 100.0)	89.2 ± 15.8 (36.0 to 100.0)	.123
P value	<.001	<.001	<.001
Improvement	20.2 ± 18.1 (–28.0 to 52.0)	20.0 ± 17.1 (–23.0 to 57.0)	21.9 ± 22.1 (–70.3 to 77.0)	.711
NAHS
Preoperative	63.1 ± 16.7 (23.8 to 93.8)	67.1 ± 18.3 (26.3 to 96.3)	65.8 ± 16.7 (23.0 to 99.0)	.360
Latest	82.6 ± 19.2 (17.5 to 100.0)	87.8 ± 13.8 (42.5 to 100.0)	88.9 ± 15.4 (20.0 to 100.0)	.112
P value	<.001	<.001	<.001
Improvement	19.1 ± 20.9 (–53.8 to 58.8)	20.6 ± 20.0 (–28.8 to 63.8)	20.5 ± 23.8 (–80.0 to 73.8)	.894
HOS-SSS
Preoperative	45.6 ± 19.2 (0.0 to 83.0)	43.4 ± 24.8 (0.0 to 94.0)	45.2 ± 20.4 (0.0 to 100.0)	.802
Latest	75.1 ± 26.8 (2.8 to 100.0)	77.4 ± 26.5 (11.1 to 100.0)	82.6 ± 23.4 (0.0 to 100.0)	.087
P value	<.001	<.001	<.001
Improvement	28.5 ± 27.3 (–44.5 to 86.1)	33.0 ± 31.6 (–36.3 to 89.0)	34.1 ± 33.2 (–81.0 to 100.0)	.491
VAS pain
Preoperative	5.9 ± 2.3 (0.0 to 9.0)	4.5 ± 2.6 (0.0 to 9.0)	5.3 ± 2.2 (0.0 to 9.7)	.005
Latest	2.3 ± 2.7 (0.0 to 10.0)	1.9 ± 2.2 (0.0 to 9.1)	1.8 ± 2.2 (0.0 to 10.0)	.491
P value	<.001	<.001	<.001
Improvement	−3.5 ± 3.3 (–9.0 to 7.0)	−2.7 ± 3.1 (–8.2 to 7.1)	−3.5 ± 3.0 (–9 to 5.0)	.144
iHOT-12	74.1 ± 27.3 (3.8 to 100.0)	79.3 ± 22.1 (19.5 to 100.0)	80.9 ± 22.8 (0.0 to 100.0)	.336
SF-12
Mental	54.8 ± 8.5 (29.9 to 66.9)	55.9 ± 7.9 (26.3 to 67.2)	56.5 ± 7.1 (22.8 to 69.3)	.387
Physical	50.3 ± 8.1 (22.5 to 61.9)	51.4 ± 7.1 (33.0 to 59.5)	51.7 ± 8.1 (18.7 to 64.3)	.273
VR-12
Mental	59.9 ± 8.2 (35.1 to 68.6)	60.9 ± 7.8 (36.0 to 68.2)	61.6 ± 7.1 (30.9 to 69.0)	.402
Physical	51.8 ± 7.6 (23.4 to 59.4)	53.0 ± 6.2 (35.9 to 60.9)	53.1 ± 7.6 (21.0 to 62.5)	.334
Patient satisfaction	8.4 ± 1.9 (3.0 to 10.0)	8.7 ± 1.6 (2.0 to 10.0)	8.4 ± 2.1 (0.0 to 10.0)	.841

Values are presented as mean ± SD (range) or n (%). Bold indicates P < .05. P value calculation is for the comparison between all three groups (first side bilateral surgery, second side bilateral surgery, and unilateral cohort). HOS-SSS, Hip Outcome Score–Sports Specific Subscale; iHOT-12, International Hip Outcome Tool–12; mHHS, modified Harris Hip Score; NAHS, Non-arthritic Hip Scope; SF-12, 12-Item Short Form Health Survey; VAS, visual analog scale; VR-12, Veterans RAND 12-Item Health Survey.

Table 6

Rates of the MCID and PASS^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
mHHS
MCID: 8	52 (76.5)	49 (72.1)	165 (80.9)	.288
PASS: 74	53 (77.9)	60 (88.2)	173 (84.8)	.237
MOIST: 54.8	45 (66.2)	48 (70.6)	149 (73.0)	.553
HOS-SSS
MCID: 6	54 (79.4)	55 (80.9)	165 (80.9)	.963
PASS: 75	39 (57.4)	44 (64.7)	142 (69.6)	.173

Values are presented as n (%). Hip Outcome Score–Sports Specific Subscale; MCID, minimal clinically important difference; mHHS, modified Harris Hip Score; MOIST, maximum outcome improvement score threshold; PASS, patient acceptable symptomatic state.

Among those who attempted to RTS, 49 (81.7%) bilateral cohort athletes and 130 (81.8%) unilateral cohort athletes returned to sports (P = .987). There was no difference between the bilateral and unilateral cohorts with respect to RTS rates or characteristics of those who did and did not RTS (P > .05). Tables 7 to 9 present RTS outcomes for both groups.

Table 7

Return-to-Sports Outcomes^a

	Bilateral	Unilateral	P Value
Returned to sports	49 (81.7)	130 (81.8)	.987
Did not return to sports
Hip pain	11 (18.3)	29 (18.2)
Lifestyle transition	8	45

Values are presented as n (%). Return-to-sports percentage does not include patients who underwent a lifestyle transition.

Table 8

Characteristics of Patients Who Did Return to Sports^a

	Bilateral	Unilateral	P Value
Sex			.800
Female	28 (57.1)	77 (59.2)
Male	21 (42.9)	53 (40.8)
Level			.963
High school	31 (63.3)	82 (63.1)
College	13 (26.5)	33 (25.4)
Professional	5 (10.2)	15 (11.5)
Ability after returning			.704
Lower	5 (17.2)	15 (21.7)
Same	16 (55.2)	36 (52.2)
Higher	8 (27.6)	18 (26.1)

Values are presented as n (%). Information regarding ability after return to sports was not available for all patients.

Table 9

Characteristics of Patients Who Did Not Return to Sports Because of Hip Symptoms^a

	Bilateral	Unilateral	P Value
Sex			.859
Female	9 (81.8)	23 (79.3)
Male	2 (18.2)	6 (20.7)
Level			.418
High school	8 (72.7)	18 (62.1)
College	1 (9.1)	8 (27.6)
Professional	2 (18.2)	3 (10.3)

Values are presented as n (%).

Secondary Surgery

Regarding revision arthroscopies, 16 (7.8%) unilateral cohort athletes underwent a revision, and 8 (11.8%) bilateral cohort athletes underwent a secondary arthroscopy on the first operative side and 3 (4.4%) on the second side (P = .283). There was no significant difference in revision rate or time to revision between the groups (Table 10). Additionally, by latest follow-up, no bilateral cohort athlete had undergone conversion to total hip arthroplasty on either side, while 1 (0.5%) unilateral cohort athlete had undergone conversion at 115.2 months postoperatively (P > .999).

Table 10

Secondary Surgery^a

	Bilateral
	First Side	Second Side	Unilateral	P Value
Revision arthroscopies	8 (11.8)	3 (4.4)	16 (7.8)	.283
Time to revision arthroscopy, mo	28.9 ± 19.2 (9.1-40.4)	17.9 ± 4.8 (17.3-23.0)	29.5 ± 24.1 (1.8-74.1)	.359

Values are presented as No. (%) or mean ± SD (range). P value calculation is for the comparison between all three groups (first side bilateral surgery, second side bilateral surgery, and unilateral cohort).

Discussion

The primary finding of this study was that high-level athletes who underwent bilateral hip arthroscopy demonstrated favorable RTS rates and statistically significant improvements in all measured PROs. From a clinical standpoint, these athletes achieved the MCID, PASS, and MOIST for the mHHS and the MCID and PASS for HOS-SSS at high rates. When compared with a propensity-matched control group of athletes who underwent unilateral hip arthroscopy, athletes who underwent bilateral hip arthroscopy had similar rates of clinical success and RTS.

Several studies in the hip preservation literature have evaluated high-level athletes and found high levels of clinical success and RTS rates.^5,6,13,46 More recently, studies have evaluated outcomes of high-level athletes undergoing bilateral hip arthroscopy and demonstrated promising outcomes at short-term follow-up (minimum, 1 year).⁶⁰ While PROs and RTS rates are frequently reported in this population, few have identified rates of achieving the MOIST.⁵⁰ The MOIST has been defined as the patient’s change in functional score divided by one’s total possible improvement. While the MCID and PASS are influenced by a patient’s preoperative outcome score, the MOIST is able to limit potential ceiling effects by accounting for total possible improvement.^{1,11,12,15,38} This holds particular promise in the athletic population where preoperative outcome scores are more subject to the ceiling effect than the general population.¹⁹

In the general population and especially the athletic population, there is a paucity of literature on outcomes after bilateral hip arthroscopy. Kuhns et al³⁷ evaluated 43 nonathlete patients undergoing bilateral hip arthroscopy and compared them with a matched control group of patients undergoing unilateral hip arthroscopy. They found that both groups had significant improvements in PROs at minimum 2-year follow-up; however, there was less improvement in the mHHS and VAS pain score in the bilateral group when compared with the unilateral group. The present study demonstrated similar success in an athletic population.

It has been hypothesized that RTS rates after bilateral hip arthroscopy would be equal to the square of the RTS rate in athletes undergoing unilateral hip arthroscopy.⁶⁰ Given this, the similar rates of RTS in athletes undergoing bilateral hip arthroscopy versus unilateral hip arthroscopy in the present study (81.7% vs 81.8%, P = .987) may seem counterintuitive. The results of the present study suggested that the outcome of bilateral hip arthroscopy statistically behaves like a dependent event rather than an independent event. This is supported by the findings of Hassebrock et al,³¹ who compared PROs among 133 patients undergoing bilateral hip arthroscopy and found similar outcomes between surgical sides.

Strengths

There are several strengths in the present study, reinforcing the findings reported. To the best of our knowledge, this is one of the few studies to investigate clinical outcomes in high-level athletes after bilateral hip arthroscopy and the first to compare this cohort with a unilateral control group. Additionally, propensity score matching was utilized in this analysis to minimize the effects of potential confounding factors, such as sex, age, Tönnis grade, BMI, follow-up time, and sports competition level. Based on an a priori power analysis, the sample sizes of the study cohorts were adequately representative to detect statistical differences, diminishing the risk of type II error. Furthermore, the use of multiple validated functional hip outcome scores designed to assess outcomes in active patients with nonarthritic hips limits a potential ceiling effect and increases the generalizability of the results. Last, multiple clinical psychometric tools were utilized to assess clinical importance, including the MCID, PASS, and MOIST.²⁹

Limitations

Limitations of the present study must be acknowledged. First, as this was a nonrandomized study, additional confounding variables may have influenced the results. Although data were prospectively collected, the retrospective nature of this analysis may have introduced bias. Additionally, analysis was based on patients from a single experienced high-volume hip preservation surgeon, which may limit the generalizability of the results or lead to nonreproducible findings at other centers. Surgical technique evolved and improved substantially over the study period, which may have introduced bias to the results. As a result, some patients in the present study who underwent interportal capsulotomy without repair or selective labral debridement would currently be treated with capsular repair/plication and an alternative labral restoration technique such as labral repair, reconstruction, or augmentation.^16,25,59 The inclusion of high school, collegiate, and professional athletes may have introduced heterogeneity in terms of competition and ability level, limiting the generalizability of the results. Furthermore, the interval between the first and second hip arthroscopy was not standardized in this study, and no conclusions were able to be made regarding the timing of a staged procedure, which has been a recent topic of interest.³¹ Last, the present study was based on minimum 2-year follow-up, but longer follow-up is necessary to determine the durability of the results.

Conclusion

High-level athletes who undergo staged bilateral primary hip arthroscopy for FAIS may expect favorable PROs and RTS rates at minimum 2-year follow-up. These results were comparable with those of a propensity-matched control group of high-level athletes who underwent unilateral primary hip arthroscopy.

Footnotes

Submitted March 16, 2021; accepted June 7, 2021.

One or more of the authors has declared the following potential conflict of interest or source of funding: D.R.M. has received nonfinancial support from Arthrex, Stryker, Smith + Nephew, and Ossur. B.R.S. has received grants from Arthrex, speaker fees from DJO Global, and education support from Smith + Nephew and Medwest Associates. A.C.L. has received education support from Arthrex, Medwest, and Smith + Nephew; research support from Arthrex, Stryker, and Medacta; hospitality payments from Smith + Nephew, Stryker, Zimmer Biomet, Arthrex; and consulting fees from Arthrex and Graymont Medical. B.G.D. has had ownership interests in Hinsdale Orthopaedics, the American Hip Institute, SCD#3, North Shore Surgical Suites, and Munster Specialty Surgery Center; has received research support from Arthrex, ATI, the Kauffman Foundation, Stryker, and Pacira Pharmaceuticals; has received consulting fees from Adventist Hinsdale Hospital, Arthrex, MAKO Surgical, Medacta, Pacira Pharmaceuticals, and Stryker; has received education support from Arthrex, Breg, and Medwest; has received honoraria from Medacta; and receives royalties from Amplitude, Arthrex, DJO Global, MAKO Surgical, Medacta, Stryker, and Orthomerica. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

ORCID iDs

Jade S. Owens

Ajay C. Lall

References

Agarwalla

Puzzitiello

Liu

, et al. Timeline for maximal subjective outcome improvement after anterior cruciate ligament reconstruction. Am J Sports Med. 2019;47(10):2501-2509. doi:10.1177/0363546518803365

Agricola

Bessems

JHJM

Ginai

, et al. The development of cam-type deformity in adolescent and young male soccer players. Am J Sports Med. 2012;40(5):1099-1106. doi:10.1177/0363546512438381

Ali

Prieto-Alhambra

Lopes

, et al. Propensity score methods in health technology assessment: principles, extended applications, and recent advances. Front Pharmacol. 2019;10:973. doi:10.3389/fphar.2019.00973

Alradwan

Philippon

Farrokhyar

, et al. Return to preinjury activity levels after surgical management of femoroacetabular impingement in athletes. Arthroscopy. 2012;28(10):1567-1576. doi:10.1016/j.arthro.2012.03.016

Amenabar

O’Donnell

. Return to sport in Australian Football League footballers after hip arthroscopy and midterm outcome. Arthroscopy. 2013;29(7):1188-1194. doi:10.1016/j.arthro.2013.05.001

Anderson

Keene

. Results of arthroscopic iliopsoas tendon release in competitive and recreational athletes. Am J Sports Med. 2008;36(12):2363-2371. doi:10.1177/0363546508322130

Aprato

Jayasekera

Villar

. Does the modified Harris Hip Score reflect patient satisfaction after hip arthroscopy? Am J Sports Med. 2012;40(11):2557-2560. doi:10.1177/0363546512460650

Austin

. Optimal caliper widths for propensity-score matching when estimating differences in means and differences in proportions in observational studies. Pharm Stat. 2011;10(2):150-161. doi:10.1002/pst.433

Austin

. Some methods of propensity-score matching had superior performance to others: results of an empirical investigation and Monte Carlo simulations. Biometrical J. 2009;51(1):171-184. doi:10.1002/bimj.200810488

10.

Barton

Salineros

Rakhra

Beaulé

. Validity of the alpha angle measurement on plain radiographs in the evaluation of cam-type femoroacetabular impingement. Clin Orthop Relat Res. 2011;469(2):464-469. doi:10.1007/s11999-010-1624-x

11.

Beck

Gowd

Liu

, et al. How is maximum outcome improvement defined in patients undergoing shoulder arthroscopy for rotator cuff repair? A 1-year follow-up study. Arthroscopy. Published online March 20, 2020. doi:10.1016/j.arthro.2020.02.047

12.

Berglund

Damodar

Vakharia

, et al. Predicting outstanding results after anatomic total shoulder arthroplasty using percentage of maximal outcome improvement. J Shoulder Elbow Surg. 2019;28(2):349-356. doi:10.1016/j.jse.2018.08.016

13.

Casartelli

Leunig

Maffiuletti

Bizzini

. Return to sport after hip surgery for femoroacetabular impingement: a systematic review. Br J Sports Med. 2015;49(12):819. doi:10.1136/bjsports-2014-094414

14.

Chahal

Thiel

GSV

Mather

Lee

Salata

Nho

. The minimal clinical important difference (MCID) and patient acceptable symptomatic state (PASS) for the modified Harris Hip Score and Hip Outcome Score among patients undergoing surgical treatment for femoroacetabular impingement. Orthop J Sports Med. 2014;2(7)(suppl 2):2325967114S00105. doi:10.1177/2325967114S00105

15.

Chahal

Van Thiel

Mather

, et al. The patient acceptable symptomatic state for the modified Harris Hip Score and Hip Outcome Score among patients undergoing surgical treatment for femoroacetabular impingement. Am J Sports Med. 2015;43(8):1844-1849. doi:10.1177/0363546515587739

16.

Chandrasekaran

Darwish

, et al. Arthroscopic reconstruction of the irreparable acetabular labrum: a match-controlled study. Arthroscopy. 2019;35(2):480-488. doi:10.1016/j.arthro.2018.09.024

17.

Chandrasekaran

Gui

Walsh

Lodhia

Suarez-Ahedo

Domb

. Correlation between changes in visual analog scale and patient-reported outcome scores and patient satisfaction after hip arthroscopic surgery. Orthop J Sports Med. 2017;5(9):2325967 117724772. doi:10.1177/2325967117724772

18.

Christensen

Althausen

Mittleman

Lee

McCarthy

. The nonarthritic hip score: reliable and validated. Clin Orthop Relat Res. 2003;406:75-83. doi:10.1097/01.blo.0000043047.84315.4b

19.

Clapp

Nwachukwu

Beck

Jan

Gowd

Nho

. Comparing outcomes of competitive athletes versus nonathletes undergoing hip arthroscopy for treatment of femoroacetabular impingement syndrome. Am J Sports Med. 2020;48(1):159-166. doi:10.1177/0363546519885359

20.

Clohisy

Carlisle

Beaulé

, et al. A systematic approach to the plain radiographic evaluation of the young adult hip. J Bone Joint Surg Am. 2008;90(suppl 4):47-66. doi:10.2106/JBJS.H.00756

21.

Degen

Fields

Wentzel

, et al. Return-to-play rates following arthroscopic treatment of femoroacetabular impingement in competitive baseball players. Phys Sportsmed. 2016;44(4):385-390. doi:10.1080/00913847.2016.1226123

22.

Domb

Annin

Chen

, et al. Optimal treatment of cam morphology may change the natural history of femoroacetabular impingement. Am J Sports Med. 2020;48(12):2887-2896. doi:10.1177/0363546520949541

23.

Domb

Chaharbakhshi

Rybalko

Litrenta

Perets

. Outcomes of hip arthroscopic surgery in patients with Tonnis grade 1 osteoarthritis at a minimum 5-year follow-up: a matched-pair comparison with a Tonnis grade 0 control group. Am J Sports Med. 2017;45(10):2294-2302. doi:10.1177/0363546517706957

24.

Domb

Chen

, et al. Predictors of clinical outcomes after hip arthroscopy: 5-year follow-up analysis of 1038 patients. Am J Sports Med. 2021;49(1):112-120. doi:10.1177/036354 6520968896

25.

Domb

Hartigan

Perets

. Decision making for labral treatment in the hip: repair versus débridement versus reconstruction. J Am Acad Orthop Surg. 2017;25(3):e53-e62. doi:10.5435/JAAOS-D-16-00144

26.

Ekhtiari

de Sa

Haldane

, et al. Hip arthroscopic capsulotomy techniques and capsular management strategies: a systematic review. Knee Surg Sports Traumatol Arthrosc. 2017;25(1):9-23. doi:10.1007/s00167-016-4411-8

27.

Essilfie

Bloom

Zusmanovich

Kester

Wolfson

Youm

. Staged bilateral hip arthroscopy compared with a matched unilateral hip arthroscopy group: minimum 2-year follow-up. Arthroscopy. 2020;36(7):1856-1861. doi:10.1016/j.arthro.2020.02.025

28.

Gerhardt

Romero

Silvers

Harris

Watanabe

Mandelbaum

. The prevalence of radiographic hip abnormalities in elite soccer players. Am J Sports Med. 2012;40(3):584-588. doi:10.1177/0363546511432711

29.

Harris

Brand

Cote

Faucett

Dhawan

. Research pearls: the significance of statistics and perils of pooling, part 1: clinical versus statistical significance. Arthroscopy. 2017;33(6):1102-1112. doi:10.1016/j.arthro.2017.01.053

30.

Harris

Kapron

Peters

Anderson

. Correlations between the alpha angle and femoral head asphericity: implications and recommendations for the diagnosis of cam femoroacetabular impingement. Eur J Radiol. 2014;83(5):788-796. doi:10.1016/j.ejrad.2014.02.005

31.

Hassebrock

Chhabra

Makovicka

Economopoulos

. Bilateral hip arthroscopy in high-level athletes: results of a shorter interval between staged bilateral hip arthroscopies. Am J Sports Med. 2020;48(3):654-660. doi:10.1177/0363546519895259

32.

Hassebrock

Makovicka

Chhabra

, et al. Hip arthroscopy in the high-level athlete: does capsular closure make a difference? Am J Sports Med. 2020;48(10):2465-2470. doi:10.1177/0363546520 936255

33.

Hawellek

Hubert

Hischke

, et al. Calcification of the acetabular labrum of the hip: prevalence in the general population and relation to hip articular cartilage and fibrocartilage degeneration. Arthritis Res Ther. 2018;20(1):104. doi:10.1186/s13075-018-1595-y

34.

Jessel

Zurakowski

Zilkens

Burstein

Gray

Kim

Y-J

. Radiographic and patient factors associated with pre-radiographic osteoarthritis in hip dysplasia. J Bone Joint Surg Am. 2009;91(5): 1120-1129. doi:10.2106/JBJS.G.00144

35.

Kapron

Peters

Aoki

, et al. The prevalence of radiographic findings of structural hip deformities in female collegiate athletes. Am J Sports Med. 2015;43(6):1324-1330. doi:10.1177/0363546515576908

36.

Klingenstein

Zbeda

Bedi

Magennis

Kelly

. Prevalence and preoperative demographic and radiographic predictors of bilateral femoroacetabular impingement. Am J Sports Med. 2013;41(4):762-768. doi:10.1177/0363546513476854

37.

Kuhns

Hannon

Makhni

, et al. A comparison of clinical outcomes after unilateral or bilateral hip arthroscopic surgery: age- and sex-matched cohort study. Am J Sports Med. 2017;45(13): 3044-3051. doi:10.1177/0363546517719020

38.

Kvien

Heiberg

Hagen

. Minimal clinically important improvement/difference (MCII/MCID) and patient acceptable symptom state (PASS): what do these concepts mean? Ann Rheum Dis. 2007;66(suppl 3):iii40-iii41. doi:10.1136/ard.2007.079798

39.

Kwon

Sawatzky

. Examining gender-related differential item functioning of the Veterans RAND 12-Item Health Survey. Qual Life Res. 2017;26(10):2877-2883. doi:10.1007/s11136-017-1638-x

40.

Lall

Annin

Chen

, et al. Achieving a perfectly spherical femoroplasty: pearls, pitfalls, and optimal surgical technique. Arthrosc Tech. 2020;9(3):e303-e313. doi:10.1016/j.eats.2019.10.011

41.

Lall

Saadat

Battaglia

Maldonado

Perets

Domb

. Perineal pressure during hip arthroscopy is reduced by use of Trendelenburg: a prospective study with randomized order of positioning. Clin Orthop Relat Res. 2019;477(8):1851-1857. doi:10.1097/CORR.0000000000000804

42.

Larson

Sikka

Sardelli

, et al. Increasing alpha angle is predictive of athletic-related “hip” and “groin” pain in collegiate National Football League prospects. Arthroscopy. 2013;29(3):405-410. doi:10.1016/j.arthro.2012.10.024

43.

Lee

Kuhn

Draovitch

Bedi

. Return to play following hip arthroscopy. Clin Sports Med. 2016;35(4):637-654. doi:10.1016/j.csm.2016.05.008

44.

Lequesne

de Seze . False profile of the pelvis: a new radiographic incidence for the study of the hip. Its use in dysplasias and different coxopathies. Article in French. Rev Rhum Mal Osteoartic. 1961;28:643-652.

45.

Levy

Kuhns

Frank

, et al. High rate of return to running for athletes after hip arthroscopy for the treatment of femoroacetabular impingement and capsular plication. Am J Sports Med. 2017;45(1):127-134. doi:10.1177/0363546516664883

46.

Lindman

Öhlin

Desai

, et al. Five-year outcomes after arthroscopic surgery for femoroacetabular impingement syndrome in elite athletes. Am J Sports Med. Published online March 20, 2020. doi:10.1177/0363546520908840

47.

Louer

Pashos

Clohisy

Nepple

. A prospective analysis of the contralateral hip among patients with femoroacetabular impingement: what are the risk factors for disease progression? Am J Sports Med. 2018;46(10):2486-2491. doi:10.1177/0363546518786246

48.

Maldonado

Chen

Walker-Santiago

, et al. Radiographic and demographic factors can predict the need for primary labral reconstruction in hip arthroscopic surgery: a predictive model using 1398 hips. Am J Sports Med. 2020;48(1):173-180. doi:10.1177/0363546519887749

49.

Maldonado

Chen

Walker-Santiago

, et al. An intact ligamentum teres predicts a superior prognosis in patients with borderline dysplasia: a matched-pair controlled study with minimum 5-year outcomes after hip arthroscopic surgery. Am J Sports Med. 2020;48(3):673-681. doi:10.1177/0363546519898716

50.

Maldonado

Kyin

Shapira

, et al. Defining the maximum outcome improvement of the modified Harris Hip Score, the Nonarthritic Hip Score, the visual analogue scale for pain, and the International Hip Outcome Tool–12 in the arthroscopic management for femoroacetabular impingement syndrome and labral tear. Arthroscopy. Published online January 12, 2021. doi:10.1016/j.arthro.2021.01.002

51.

Maldonado

Lall

Walker-Santiago

, et al. Hip labral reconstruction: consensus study on indications, graft type and technique among high-volume surgeons. J Hip Preserv Surg. 2019;6(1):41-49. doi:10.1093/jhps/hnz008

52.

Maldonado

LaReau

Perets

, et al. Outcomes of hip arthroscopy with concomitant periacetabular osteotomy: minimum 5-year follow-up. Arthroscopy. 2019;35(3):826-834.

53.

Maldonado

Rosinsky

Shapira

Domb

. Stepwise safe access in hip arthroscopy in the supine position: tips and pearls from A to Z. J Am Acad Orthop Surg. Published online May 22, 2020. doi:10.5435/JAAOS-D-19-00856

54.

Mansor

Perets

Domb

. In search of the spherical femoroplasty: cam overresection leads to inferior functional scores before and after revision hip arthroscopic surgery. Am J Sports Med. 2018;46(9):2061-2071. doi:10.1177/036354651 8779064

55.

Martin

Kivlan

Christoforetti

, et al. Defining variations in outcomes of hip arthroscopy for femoroacetabular impingement using the 12-Item International Hip Outcome Tool (iHOT-12). Am J Sports Med. 2020;48(5):1175-1180. doi:10.1177/0363546520906408

56.

Martin

Philippon

. Evidence of validity for the Hip Outcome Score in hip arthroscopy. Arthroscopy. 2007;23(8):822-826. doi:10.1016/j.arthro.2007.02.004

57.

Nawabi

Bedi

Tibor

Magennis

Kelly

. The demographic characteristics of high-level and recreational athletes undergoing hip arthroscopy for femoroacetabular impingement: a sports-specific analysis. Arthroscopy. 2014;30(3):398-405. doi:10.1016/j.arthro.2013.12.010

58.

Ogata

Moriya

Tsuchiya

Akita

Kamegaya

Someya

. Acetabular cover in congenital dislocation of the hip. J Bone Joint Surg Br. 1990;72(2):190-196. doi:10.1302/0301-620X.72B2.23 12554

59.

Riff

Kunze

Movassaghi

, et al. Systematic review of hip arthroscopy for femoroacetabular impingement: the importance of labral repair and capsular closure. Arthroscopy. 2019;35(2):646-656.e3. doi:10.1016/j.arthro.2018.09.005

60.

Rosinsky

Kyin

Lall

Shapira

Maldonado

Domb

. Rate of return to sport and functional outcomes after bilateral hip arthroscopy in high-level athletes. Am J Sports Med. 2019;47(14): 3444-3454. doi:10.1177/0363546519885354

61.

Sansone

Ahldén

Jonasson

, et al. Good results after hip arthroscopy for femoroacetabular impingement in top-level athletes. Orthop J Sports Med. 2015;3(2):2325967115569691. doi:10.1177/2325967115569691

62.

Seldes

Tan

Hunt

Katz

Winiarsky

Fitzgerald

. Anatomy, histologic features, and vascularity of the adult acetabular labrum. Clin Orthop Relat Res. 2001;382:232-240.

63.

Vigdorchik

Nepple

Eftekhary

Leunig

Clohisy

. What is the association of elite sporting activities with the development of hip osteoarthritis? Am J Sports Med. 2017;45(4):961-964. doi:10.1177/0363546516656359

64.

Ware

Kosinski

Keller

. A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34(3):220-233.

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