- Email: [email protected]
Performance and Return to Sport After Hip Arthroscopy in the National Basketball Association
Performance and Return to Sport After Hip Arthroscopy in the National Basketball Association Robert A. Jack II, M.D., Kyle R. Sochacki, M.D., Takashi Hirase, M.D., Justin Vickery, M.D., Patrick C. McCulloch, M.D., David M. Lintner, M.D., and Joshua D. Harris, M.D.
Purpose: To determine: (1) return to sport (RTS) rate in National Basketball Association (NBA) players following hip arthroscopy, (2) postoperative career length and games per season, (3) pre- and postoperative performance, and (4) postoperative performance compared with control players. Methods: NBA athletes who underwent hip arthroscopy and matched controls were identified. RTS was defined as playing in at least 1 game after surgery. Player efficiency ratings were used for performance evaluation. Continuous variables of each group were compared using a 2-tailed paired samples Student t test for normally distributed data. c2 was used to analyze categorical data. RTS was used as the primary outcome with statistical significance defined by a P value < .05. A Bonferroni correction was used to control for the remaining multiple comparisons with statistical significance defined by a P value .008. Results: Twenty-three players (24 hips) were analyzed (mean age 27.5 3.1 years; mean experience in the NBA 5.8 2.8 years at time of surgery). Small forwards (n ¼ 8, 33.3%) represented the largest proportion of players that underwent hip arthroscopy. Twenty players (21 surgeries, 87.5%) were able to RTS in NBA at an average of 5.7 2.6 months. The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2%. Players in the control group (5.2 3.5 years) had a similar career length as (P ¼ .068) players who underwent surgery (4.4 3.0 years). There was no significant (P ¼ .045) decrease in games per season following surgery. There was no significant difference in performance postoperatively compared with preoperatively (P ¼ .017) and compared with matched controls following surgery (P ¼ .570). Conclusions: The RTS rate for NBA athletes after hip arthroscopy is high. There was no decrease in games played, career lengths, or performance following hip arthroscopy in NBA players versus preoperatively and matched controls. Level of evidence: Level III casecontrol study
emoroacetabular impingement (FAI) syndrome is a common cause of hip pain due to abnormal joint morphology leading to aberrant contact between the proximal femur and acetabular rim.1-4 This can lead to decreased function and performance in elite athletes.4,5 Multiple previous investigations have demonstrated a significant increase in the risk of cam morphology development in adolescent athletes playing a high-
F
intensity sport.6,7 In turn, there is a significantly greater rate of cam morphology in athletes versus nonathletes.8 Basketball players are at high risk for developing symptoms due to the repetitive high loading forces across the hip.9 As such, basketball players have an increased prevalence of cam morphology versus agematched controls not participating in elite level basketball.7,10
From Houston Methodist Orthopedic and Sports Medicine, Houston, Texas (R.A.J., K.R.S., T.H., P.C.M., D.M.L., J.D.H.); and Vanderbilt University Medical Center Orthopaedic Surgery and Rehabilitation, Nashville, Tennessee (J.V.), U.S.A. The authors report the following potential conflicts of interest or sources of funding: P.C.M. reports speaker’s bureau/paid presentation by company/ supplier (Vericel/Aastroom Biosciences); research support from company/ supplier (DePuy, A Johnson & Johnson Company; Arthrex/Medinc of Texas); and medical/orthopaedic publications editorial/governing board (Journal of Knee Surgery; Orthobullets.com). D.M.L. reports educational support; Arthrex/Medinc of Texas. J.D.H. reports AAOS: Board or committee member; American Journal of Orthopedics: editorial or governing board; American Orthopaedic Society for Sports Medicine: board or committee member; Arthroscopy: editorial or governing board; Arthroscopy Association of North America: board or committee member; DePuy, A Johnson & Johnson
Company: research support; Frontiers in Surgery: editorial or governing board; International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine: board or committee member; NIA Magellan: paid consultant; Ossur: paid consultant, paid presenter or speaker; SLACK Incorporated: publishing royalties, financial or material support; and Smith & Nephew: paid consultant, paid presenter or speaker, research support. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Received June 12, 2019; accepted September 10, 2019. Address correspondence to Joshua D. Harris, 6445 Main St., Suite 2500, Houston, TX 77030. E-mail: [email protected] Ó 2019 by the Arthroscopy Association of North America 0749-8063/19746/$36.00 https://doi.org/10.1016/j.arthro.2019.09.013
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol
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Previous studies have examined the epidemiology and outcomes of arthroscopic hip preservation surgery for FAI syndrome in professional athletes.11-16 The return to sports (RTS) rate in these professional athletes from the National Football League (NFL), Major League Baseball, National Hockey League, and Major League Soccer has been reported to range from 88% to 96% at an average of 5.4 to 9.2 months postoperatively with significant improvement in several patient-reported outcome measures.11,13,14,17-19 Importantly, these studies have also demonstrated RTS without decreased performance statistics. However, there are few studies investigating RTS and performance in National Basketball Association (NBA) players following hip arthroscopy. Given this limited evidence and the increasing popularity of professional basketball, it is important to understand surgical outcomes in these patients. The purpose of this study was to determine the (1) RTS rate in NBA players following hip arthroscopy, (2) postoperative career length and games per season, (3) pre- and postoperative performance, and (4) postoperative performance compared with control players. The authors hypothesized that NBA players who underwent hip arthroscopy would have (1) a greater than 85% RTS rate, (2) no significant difference in postoperative career length and games per season compared with matched controls, (3) no significant difference in postoperative performance compared with preoperative, and (4) no significant performance difference postoperative when compared with matched controls.
Methods Professional athletes from the NBA who underwent hip arthroscopy between January 2000 and December 2017 were identified through team websites, publicly available Internet-based injury reports, player profiles and biographies, and press releases. The search was manually conducted by 2 orthopaedic surgery residents in December 2017. Searches were performed for all professional teams. This method of data collection has been used successfully in multiple previous studies of professional athletes, including those in the NBA.20-29 All players identified were included in this study as it related to RTS rate. A player was deemed to have RTS if he played in any regular season game after surgery. A player did not RTS if he did not play in any game after surgery. Inclusion criteria were any player on an active roster before hip arthroscopy. Players were included if they were found to have undergone hip arthroscopy as reported by at least 2 separate sources. Information from these sources was verified against each other and through independent web-based searches of team press releases that confirmed the date of surgery for each player. If this information was
unclear, unverified, or unable to be obtained, then the athlete was excluded. Athletes who were injured and underwent procedures before completing their first regular season were excluded because no preoperative data would be available for comparison. Players who underwent hip arthroscopy in the 2017-2018 season were excluded from analysis because they had less than a 1-year opportunity to RTS and to obtain postoperative statistics. Demographic data were collected including each player’s age, position, date of injury, and date of surgery. Players were categorized by their positions, including center, power forward, small forward, shooting guard, and point guard. Due to the possible benefits or detriments of aging and/or experience on player performance and number of games played, matched control players were selected to use for comparison with postsurgery performance in the surgically treated players. Controls were matched to study cases based on position, age (1 year), years of experience (1 year), body mass index, and performance data before the surgery date. Each control was given an index date that matched the case player’s surgery date to compare postoperative and post-index performance. For example, if a player had surgery 3 years into his career, the control’s index date were 3 years into his career. Performance statistics were collected from www. basketball-reference.com for each player identified before and after hip arthroscopy. Statistics were collected for regular season NBA games only, with preseason and playoff games excluded. There were no players for whom performance data could not be identified. Player statistics for cases preoperative and postoperative and controls pre-index and post-index were collected and aggregated. Each performance data category was divided by the games played to account for discrepancies in the number of games played per season. Player efficiency rating (PER) was used for performance data used for comparison as previously described.29 PER is a per minute rating that sums up all a player’s positive accomplishments, subtracts the negative accomplishments, and returns a per-minute rating of a player’s performance. A KaplaneMeier survivorship curve with “retirement” as the endpoint was constructed postoperatively for cases and post-index for controls. The continuous variables of each cohort were compared using a 2-tailed paired samples Student t test for normally distributed data. c2 was used to analyze categorical data. Significance was set using an a value of .05. RTS was used as the primary outcome with statistical significance defined by a P value <.05. A Bonferroni correction was used to control for the remaining multiple comparisons with statistical significance defined by a P value .008.14,20
3
Online search of publicly available data for NBA players who underwent hip arthroscopy surgery from 2001 to 2017 (31 players)
No femoroacetabular impingement (FAI) surgery (2 players)
Screening
IdenƟficaƟon
RTS AFTER HIP ARTHROSCOPY IN THE NBA
No professional experience (1 player)
Eligibility
Fig 1. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart illustrating application of exclusion criteria to determine the final number of professional athletes analyzed in this study. FAI, femoroacetabular impingement; NBA, National Basketball Association.
NBA players who underwent FAI surgery (29 players)
Inadequate Ɵme in league (< 1 year) (3 players)
Inadequate follow up Ɵme (< 1 year) (2 players)
Included
FAI Surgery in the NBA (23 players, 24 surgeries)
Returned to sport (18 players, 19 surgeries)
Results Twenty-three players (24 hips) underwent hip arthroscopy from January 2000 to December 2017 (Fig 1). The mean age was 27.5 3.1 years, and the mean experience in the NBA was 5.8 2.8 years at time of surgery. Seven hip surgeries (29.2%) were performed in the offseason. One player had bilateral surgery 3 years apart and returned to sport after both surgeries. There were no revision surgeries. Small forwards (n ¼ 8) represented the largest proportion of players that underwent hip arthroscopy (33.3%) (Table 1). There were no significant differences in demographic, performance, and games per season data between cases and matched controls presurgery and pre-index. Twenty players (21 hips, 87.5%) were able to RTS in NBA at an average of 5.7 2.6 months (Table 1). The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2% (Fig 2). Players in
Returned to sport, reƟred within 1 year (2 players, 2 surgeries)
Did not return to sport (3 players, 3 surgeries)
the control group (5.2 3.4 years) were in the NBA a similar number of years as (P ¼ .068) players who underwent hip arthroscopy (4.4 3.0 years). There was no significant decrease in games per season preoperatively compared with postoperatively and between postoperative cases and post-index controls (Tables 2 and 3). There was no significant decrease in PER/season for cases preoperatively compared with Table 1. Time to RTS by Position Position C PF SF SG PG Overall
n 4 4 8 1 7 24
RTS, % 75.0 100.0 75.0 100.0 100.0 87.5
Months to RTS 2.2 1.0 6.1 2.6 7.1 2.5 7.1 8.6 6.8 5.7 2.6
C, center; PF, power forward; PG, point guard; RTS, return to sport; SF, small forward; SG, shooting guard.
4
R. A. JACK ET AL. 100% 90%
PERCENT SURVIVAL
80% 70% 60% 50% 40% 30% 20% 10% 0% 0
1
2
3
4
5
Cases
6 YEAR
7
8
9
10
11
12
13
Controls
Fig 2. KaplaneMeier survival analysis for cases and controls. Zero (0) signifies year of surgery for cases and index year for controls.
postoperatively (Table 3). There was no significant decrease in PER/season for cases postoperatively compared with controls post-index.
Discussion The study hypotheses were confirmed, with an 87.5% RTS rate for NBA players following hip arthroscopy. NBA athletes played similar games per season and career lengths postoperatively compared with preoperatively and matched controls. There was also no significant difference in performance compared with preoperatively and matched controls following surgery. The RTS rate in high-level basketball players has been previously reported to be 100% at an average of 2 to 3 months postoperatively.30,31 This is greater and faster than the current study, with a RTS rate of 87.5% at slightly less than 6 months. The lower RTS rate in the current study may be attributable to only including NBA players, whereas the other studies included high school and collegiate athletes. In addition, the definition of RTS is unclear in the previous studies, whereas the current study only considered a player to RTS if they played in an NBA regular season game following surgery with preseason and the developmental league not counting toward RTS. In the current study, only 5 NBA players were able to RTS in the same season as their surgery, and 78.9% of NBA players were in the
offseason during the recovery period of surgery. Therefore, the RTS time is likely inflated due to being in the offseason when the players were cleared to RTS. There are limited data regarding career length and games per season for NBA players undergoing hip arthroscopy. The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2%, with no significant differences in career length and games per season between players undergoing hip arthroscopy and control players post-index. This same trend was seen in NFL players undergoing hip arthroscopy, with hip arthroscopy having no significant effect on career length and games per season following surgery compared with preoperatively and matched controls.13 Both cases and controls demonstrated a postoperative or post-index decline in games per season, respectively. However, there was no significant difference between the groups. This indicates that this may be a function of normal age-associated decline as opposed to a result of surgery. In addition, both the postoperative cases and postindex controls experienced a similar decline in performance compared with preoperative and pre-index levels. However, this decline was not statistically significant compared with preoperatively and compared with matched controls. These findings are similar to a recent study in NFL players following hip arthroscopy that found no significant performance differences postoperatively compared with matched controls.13 This is an incredibly important aspect of perioperative discussions with NBA players, teams, coaches, trainers, and basketball players aspiring to play in the NBA (developmental leagues, college, high school): following arthroscopic hip preservation surgery, players return with similar performance statistics compared with their preoperative levels and compared with matched controls. This study was not able to assess the outcomes of NBA players with FAI treated nonoperatively. The most common position undergoing hip arthroscopy was small forward (n ¼ 8, 33.3%) followed by point guard (n ¼ 7, 29.4%). The high prevalence is likely due to the repetitive high loading forces across the hip demanded by playing the positions. Small forward and point guard are typically filled by the most athletic players, requiring a significant amount of running and jumping.
Table 2. Statistics for Pre- and Postsurgery for Cases and Pre- and Post-Index for Controls Cases Statistic G/s PER/s
Preop 61.9 12.4 15.1 2.7
Postop 53.8 17.3 13.3 4.1
Controls P Value .045 .017
Pre-Index 65.7 9.3 15.4 2.9
Post-Index 62.1 15.1 14.0 3.8
NOTE. P value as determined by 2-tailed paired Student t test between pre- and postsurgery and pre- and post-index. G/s, games played per season; PER/s, player efficiency rating per season; postop, postoperative; preop, preoperative.
P Value .309 .115
5
RTS AFTER HIP ARTHROSCOPY IN THE NBA Table 3. Postsurgery and Post-Index Statistics for Cases and Controls by Position Postsurgery and Post-index Statistic Seasons G/s PER/s
Cases 4.4 3.0 53.8 17.3 13.3 4.1
Controls 5.2 3.4 62.1 15.1 14.0 3.8
P Value .068 .145 .570
NOTE. P value as determined by 2-tailed paired Student t test. G/s, games played per season; PER/s, player efficiency rating per season.
Conversely, the center and power forward positions are more stationary, potentially leading to a decreased rate of FAI.7,10 Limitations There are limitations to this study and other studies of similar methodology. There is the potential for beta error, given comparisons without significant differences and the small number of subjects include in the study. This study also only evaluated male athletes in United Statesebased professional basketball only, so it may not translate to female athletes or other sports in other nations and has led to fewer subjects compared with other sports. Also, it is highly likely that surgeries performed in the early 2000s differed from more recent surgeries due to advancement in techniques and instrumentation. The use of publicly available data to identify players who underwent hip arthroscopy may be prone to selection, reporting, and observer bias. This is especially problematic with FAI and hip arthroscopy in general, as it is a relatively new diagnosis and the treatment has evolved significantly over the years. This differs compared with other, more common injuries such as anterior cruciate ligament tear, rotator cuff tear, and elbow ulnar collateral ligament tears, which have been diagnosed and treated much more commonly and routinely in the same time frame. However, this method of data acquisition has been used in multiple previous studies.20-23,25,26 By only including the highest level of professional players, these data may only apply to elite-level athletes. In addition, the PER may not provide a comprehensive evaluation of a player’s performance despite being used by several previous studies. Professional players have a greater rate of return to play than nonprofessional players.32 This is believed to be due to the inherently high talent and determination present at this level, with greater income potential and financial incentive to return.33 In addition, players may retire due to other nonperformancerelated reasons that are not able to be accounted for in this type of study. The authors may not have been able to identify all previous hip surgeries for the included players, which has been shown to have an effect on the outcomes of hip arthroscopy.34,35 Also,
career length and performance was not adjusted for “time missed” for players who underwent hip arthroscopy. Inherent to this type of study, there are multiple unknown confounding variables such no direct physical contact, patient-reported outcomes, or medical records access to corroborate diagnosis and treatment. The use of public data limits the ability to determine the chronicity and severity of the injury. It was also unable to be determined reliably the surgeon who performed the operation or exact operative procedure used in each hip arthroscopy (labral debridement vs repair vs reconstruction, degree of cam/pincer correction/undercorrection/overcorrection, chondral treatments for variable degrees of articular cartilage pathology/ arthritis, or capsular closure/repair/plication/shift; periarticular extra-articular peritrochanteric, deep gluteal space, or athletic pubalgia/core muscle injury). Heterogeneity of surgeons or surgeon experience is also a limitation. Other limitations include the absence of patient-reported outcomes and incomplete follow-up and career length for players still in their respective leagues. It is also possible that by performing a Bonferroni correction, the present study could miss a difference that does exist.
Conclusions The RTS rate for NBA athletes after hip arthroscopy is high. There was no decrease in games played, career lengths, or performance following hip arthroscopy in NBA players versus preoperatively and matched controls.
References 1. Banerjee P, McLean CR. Femoroacetabular impingement: A review of diagnosis and management. Curr Rev Musculoskelet Med 2011;4:23-32. 2. Clohisy JC, Baca G, Beaule PE, et al. Descriptive epidemiology of femoroacetabular impingement: A North American cohort of patients undergoing surgery. Am J Sports Med 2013;41:1348-1356. 3. Clohisy JC, Knaus ER, Hunt DM, Lesher JM, HarrisHayes M, Prather H. Clinical presentation of patients with symptomatic anterior hip impingement. Clin Orthop Relat Res 2009;467:638-644. 4. Frank JS, Gambacorta PL, Eisner EA. Hip pathology in the adolescent athlete. J Am Acad Orthop Surg 2013;21: 665-674. 5. Hammoud S, Bedi A, Voos JE, Mauro CS, Kelly BT. The recognition and evaluation of patterns of compensatory injury in patients with mechanical hip pain. Sports Health 2014;6:108-118. 6. Nepple JJ, Vigdorchik JM, Clohisy JC. What is the association between sports participation and the development of proximal femoral cam deformity? A systematic review and meta-analysis. Am J Sports Med 2015;43:2833-2840. 7. Siebenrock KA, Ferner F, Noble PC, Santore RF, Werlen S, Mamisch TC. The cam-type deformity of the proximal femur arises in childhood in response to
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R. A. JACK ET AL. vigorous sporting activity. Clin Orthop Relat Res 2011;469: 3229-3240. Frank JM, Harris JD, Erickson BJ, et al. Prevalence of femoroacetabular impingement imaging findings in asymptomatic volunteers: A systematic review. Arthroscopy 2015;31:1199-1204. Domb BG, Stake CE, Finch NA, Cramer TL. Return to sport after hip arthroscopy: Aggregate recommendations from high-volume hip arthroscopy centers. Orthopedics 2014;37:e902-e905. Siebenrock KA, Behning A, Mamisch TC, Schwab JM. Growth plate alteration precedes cam-type deformity in elite basketball players. Clin Orthop Relat Res 2013;471: 1084-1091. Locks R, Utsunomiya H, Briggs KK, McNamara S, Chahla J, Philippon MJ. Return to play after hip arthroscopic surgery for femoroacetabular impingement in professional soccer players. Am J Sports Med 2018;46: 273-279. Menge TJ, Briggs KK, Dornan GJ, McNamara SC, Philippon MJ. Survivorship and outcomes 10 years following hip arthroscopy for femoroacetabular impingement: Labral debridement compared with labral repair. J Bone Joint Surg Am 2017;99: 997-1004. Nwachukwu BU, Bedi A, Premkumar A, Draovitch P, Kelly BT. Characteristics and outcomes of arthroscopic femoroacetabular impingement surgery in the National Football League. Am J Sports Med 2018;46: 144-148. Jack RA 2nd, Sochacki KR, Hirase T, Vickery JW, Harris JD. Performance and return to sport after hip arthroscopy for femoroacetabular impingement in professional athletes differs between sports. Arthroscopy 2019;35:1422-1428. Alradwan H, Philippon MJ, Farrokhyar F, et al. Return to preinjury activity levels after surgical management of femoroacetabular impingement in athletes. Arthroscopy 2012;28:1567-1576. Nawabi DH, Bedi A, Tibor LM, Magennis E, Kelly BT. The demographic characteristics of high-level and recreational athletes undergoing hip arthroscopy for femoroacetabular impingement: A sports-specific analysis. Arthroscopy 2014;30:398-405. Degen RM, Fields KG, Wentzel CS, et al. Return-to-play rates following arthroscopic treatment of femoroacetabular impingement in competitive baseball players. Phys Sportsmed 2016;44:385-390. Malviya A, Paliobeis CP, Villar RN. Do professional athletes perform better than recreational athletes after arthroscopy for femoroacetabular impingement? Clin Orthop Relat Res 2013;471:2477-2483. Philippon M, Schenker M, Briggs K, Kuppersmith D. Femoroacetabular impingement in 45 professional athletes: Associated pathologies and return to sport following arthroscopic decompression. Knee Surg Sports Traumatol Arthrosc 2007;15:908-914. Erickson BJ, Gupta AK, Harris JD, et al. Rate of return to pitching and performance after Tommy John surgery in Major League Baseball pitchers. Am J Sports Med 2014;42: 536-543.
21. Jack RA 2nd, Burn MB, Sochacki KR, McCulloch PC, Lintner DM, Harris JD. Performance and return to sport after Tommy John surgery among Major League Baseball position players. Am J Sports Med 2018;363546518762397. 22. Jack RA 2nd, Sochacki KR, Gardner SS, et al. Performance and return to sport after achilles tendon repair in National Football League players. Foot Ankle Int 2017;38: 1092-1099. 23. Jack RA 2nd, Sochacki KR, Navarro SM, McCulloch PC, Lintner DM, Harris JD. Performance and return to sport after nonoperative treatment of clavicle fractures in National Football League players. Orthopedics 2017;40: e836-e843. 24. Makhni EC, Lee RW, Morrow ZS, Gualtieri AP, Gorroochurn P, Ahmad CS. Performance, return to competition, and reinjury after Tommy John surgery in major league baseball pitchers: A review of 147 cases. Am J Sports Med 2014;42:1323-1332. 25. Sochacki KR, Jack RA 2nd, Hirase T, et al. Performance and return to sport after forearm fracture open reduction and internal fixation in National Football League Players. Hand (N Y) 2017:1558944717726137. 26. Sochacki KR, Jack RA 2nd, Nauert R, et al. Performance and return to sport after thumb ulnar collateral ligament surgery in National Football League players. Hand (N Y) 2018:1558944718760001. 27. Harris JD, Erickson BJ, Bach BR Jr, et al. Return-to-sport and performance after anterior cruciate ligament reconstruction in National Basketball Association players. Sports Health 2013;5:562-568. 28. Harris JD, Walton DM, Erickson BJ, et al. Return to sport and performance after microfracture in the knees of National Basketball Association players. Orthop J Sports Med 2013;1:2325967113512759. 29. Mai HT, Chun DS, Schneider AD, et al. Performancebased outcomes after anterior cruciate ligament reconstruction in professional athletes differ between sports. Am J Sports Med 2017;45:2226-2232. 30. Byrd JW, Jones KS. Hip arthroscopy in athletes: 10-year follow-up. Am J Sports Med 2009;37:2140-2143. 31. Mohan R, Johnson NR, Hevesi M, Gibbs CM, Levy BA, Krych AJ. Return to sport and clinical outcomes after hip arthroscopic labral repair in young amateur athletes: Minimum 2-year follow-up. Arthroscopy 2017;33: 1679-1684. 32. Nho SJ, Magennis EM, Singh CK, Kelly BT. Outcomes after the arthroscopic treatment of femoroacetabular impingement in a mixed group of high-level athletes. Am J Sports Med 2011;39:14S-19S (suppl). 33. Menge TJ, Briggs KK, Philippon MJ. Predictors of length of career after hip arthroscopy for femoroacetabular impingement in professional hockey players. Am J Sports Med 2016;44:2286-2291. 34. Domb BG, Martin TJ, Gui C, Chandrasekaran S, SuarezAhedo C, Lodhia P. Predictors of clinical outcomes after hip arthroscopy: A prospective analysis of 1038 patients with 2-year follow-up. Am J Sports Med 2018;46: 1324-1330. 35. Sardana V, Philippon MJ, de Sa D, et al. Revision hip arthroscopy indications and outcomes: A systematic review. Arthroscopy 2015;31:2047-2055.
Purpose: To determine: (1) return to sport (RTS) rate in National Basketball Association (NBA) players following hip arthroscopy, (2) postoperative career length and games per season, (3) pre- and postoperative performance, and (4) postoperative performance compared with control players. Methods: NBA athletes who underwent hip arthroscopy and matched controls were identified. RTS was defined as playing in at least 1 game after surgery. Player efficiency ratings were used for performance evaluation. Continuous variables of each group were compared using a 2-tailed paired samples Student t test for normally distributed data. c2 was used to analyze categorical data. RTS was used as the primary outcome with statistical significance defined by a P value < .05. A Bonferroni correction was used to control for the remaining multiple comparisons with statistical significance defined by a P value .008. Results: Twenty-three players (24 hips) were analyzed (mean age 27.5 3.1 years; mean experience in the NBA 5.8 2.8 years at time of surgery). Small forwards (n ¼ 8, 33.3%) represented the largest proportion of players that underwent hip arthroscopy. Twenty players (21 surgeries, 87.5%) were able to RTS in NBA at an average of 5.7 2.6 months. The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2%. Players in the control group (5.2 3.5 years) had a similar career length as (P ¼ .068) players who underwent surgery (4.4 3.0 years). There was no significant (P ¼ .045) decrease in games per season following surgery. There was no significant difference in performance postoperatively compared with preoperatively (P ¼ .017) and compared with matched controls following surgery (P ¼ .570). Conclusions: The RTS rate for NBA athletes after hip arthroscopy is high. There was no decrease in games played, career lengths, or performance following hip arthroscopy in NBA players versus preoperatively and matched controls. Level of evidence: Level III casecontrol study
emoroacetabular impingement (FAI) syndrome is a common cause of hip pain due to abnormal joint morphology leading to aberrant contact between the proximal femur and acetabular rim.1-4 This can lead to decreased function and performance in elite athletes.4,5 Multiple previous investigations have demonstrated a significant increase in the risk of cam morphology development in adolescent athletes playing a high-
F
intensity sport.6,7 In turn, there is a significantly greater rate of cam morphology in athletes versus nonathletes.8 Basketball players are at high risk for developing symptoms due to the repetitive high loading forces across the hip.9 As such, basketball players have an increased prevalence of cam morphology versus agematched controls not participating in elite level basketball.7,10
From Houston Methodist Orthopedic and Sports Medicine, Houston, Texas (R.A.J., K.R.S., T.H., P.C.M., D.M.L., J.D.H.); and Vanderbilt University Medical Center Orthopaedic Surgery and Rehabilitation, Nashville, Tennessee (J.V.), U.S.A. The authors report the following potential conflicts of interest or sources of funding: P.C.M. reports speaker’s bureau/paid presentation by company/ supplier (Vericel/Aastroom Biosciences); research support from company/ supplier (DePuy, A Johnson & Johnson Company; Arthrex/Medinc of Texas); and medical/orthopaedic publications editorial/governing board (Journal of Knee Surgery; Orthobullets.com). D.M.L. reports educational support; Arthrex/Medinc of Texas. J.D.H. reports AAOS: Board or committee member; American Journal of Orthopedics: editorial or governing board; American Orthopaedic Society for Sports Medicine: board or committee member; Arthroscopy: editorial or governing board; Arthroscopy Association of North America: board or committee member; DePuy, A Johnson & Johnson
Company: research support; Frontiers in Surgery: editorial or governing board; International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine: board or committee member; NIA Magellan: paid consultant; Ossur: paid consultant, paid presenter or speaker; SLACK Incorporated: publishing royalties, financial or material support; and Smith & Nephew: paid consultant, paid presenter or speaker, research support. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Received June 12, 2019; accepted September 10, 2019. Address correspondence to Joshua D. Harris, 6445 Main St., Suite 2500, Houston, TX 77030. E-mail: [email protected] Ó 2019 by the Arthroscopy Association of North America 0749-8063/19746/$36.00 https://doi.org/10.1016/j.arthro.2019.09.013
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol
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No
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(Month), 2019: pp 1-6
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R. A. JACK ET AL.
Previous studies have examined the epidemiology and outcomes of arthroscopic hip preservation surgery for FAI syndrome in professional athletes.11-16 The return to sports (RTS) rate in these professional athletes from the National Football League (NFL), Major League Baseball, National Hockey League, and Major League Soccer has been reported to range from 88% to 96% at an average of 5.4 to 9.2 months postoperatively with significant improvement in several patient-reported outcome measures.11,13,14,17-19 Importantly, these studies have also demonstrated RTS without decreased performance statistics. However, there are few studies investigating RTS and performance in National Basketball Association (NBA) players following hip arthroscopy. Given this limited evidence and the increasing popularity of professional basketball, it is important to understand surgical outcomes in these patients. The purpose of this study was to determine the (1) RTS rate in NBA players following hip arthroscopy, (2) postoperative career length and games per season, (3) pre- and postoperative performance, and (4) postoperative performance compared with control players. The authors hypothesized that NBA players who underwent hip arthroscopy would have (1) a greater than 85% RTS rate, (2) no significant difference in postoperative career length and games per season compared with matched controls, (3) no significant difference in postoperative performance compared with preoperative, and (4) no significant performance difference postoperative when compared with matched controls.
Methods Professional athletes from the NBA who underwent hip arthroscopy between January 2000 and December 2017 were identified through team websites, publicly available Internet-based injury reports, player profiles and biographies, and press releases. The search was manually conducted by 2 orthopaedic surgery residents in December 2017. Searches were performed for all professional teams. This method of data collection has been used successfully in multiple previous studies of professional athletes, including those in the NBA.20-29 All players identified were included in this study as it related to RTS rate. A player was deemed to have RTS if he played in any regular season game after surgery. A player did not RTS if he did not play in any game after surgery. Inclusion criteria were any player on an active roster before hip arthroscopy. Players were included if they were found to have undergone hip arthroscopy as reported by at least 2 separate sources. Information from these sources was verified against each other and through independent web-based searches of team press releases that confirmed the date of surgery for each player. If this information was
unclear, unverified, or unable to be obtained, then the athlete was excluded. Athletes who were injured and underwent procedures before completing their first regular season were excluded because no preoperative data would be available for comparison. Players who underwent hip arthroscopy in the 2017-2018 season were excluded from analysis because they had less than a 1-year opportunity to RTS and to obtain postoperative statistics. Demographic data were collected including each player’s age, position, date of injury, and date of surgery. Players were categorized by their positions, including center, power forward, small forward, shooting guard, and point guard. Due to the possible benefits or detriments of aging and/or experience on player performance and number of games played, matched control players were selected to use for comparison with postsurgery performance in the surgically treated players. Controls were matched to study cases based on position, age (1 year), years of experience (1 year), body mass index, and performance data before the surgery date. Each control was given an index date that matched the case player’s surgery date to compare postoperative and post-index performance. For example, if a player had surgery 3 years into his career, the control’s index date were 3 years into his career. Performance statistics were collected from www. basketball-reference.com for each player identified before and after hip arthroscopy. Statistics were collected for regular season NBA games only, with preseason and playoff games excluded. There were no players for whom performance data could not be identified. Player statistics for cases preoperative and postoperative and controls pre-index and post-index were collected and aggregated. Each performance data category was divided by the games played to account for discrepancies in the number of games played per season. Player efficiency rating (PER) was used for performance data used for comparison as previously described.29 PER is a per minute rating that sums up all a player’s positive accomplishments, subtracts the negative accomplishments, and returns a per-minute rating of a player’s performance. A KaplaneMeier survivorship curve with “retirement” as the endpoint was constructed postoperatively for cases and post-index for controls. The continuous variables of each cohort were compared using a 2-tailed paired samples Student t test for normally distributed data. c2 was used to analyze categorical data. Significance was set using an a value of .05. RTS was used as the primary outcome with statistical significance defined by a P value <.05. A Bonferroni correction was used to control for the remaining multiple comparisons with statistical significance defined by a P value .008.14,20
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Online search of publicly available data for NBA players who underwent hip arthroscopy surgery from 2001 to 2017 (31 players)
No femoroacetabular impingement (FAI) surgery (2 players)
Screening
IdenƟficaƟon
RTS AFTER HIP ARTHROSCOPY IN THE NBA
No professional experience (1 player)
Eligibility
Fig 1. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart illustrating application of exclusion criteria to determine the final number of professional athletes analyzed in this study. FAI, femoroacetabular impingement; NBA, National Basketball Association.
NBA players who underwent FAI surgery (29 players)
Inadequate Ɵme in league (< 1 year) (3 players)
Inadequate follow up Ɵme (< 1 year) (2 players)
Included
FAI Surgery in the NBA (23 players, 24 surgeries)
Returned to sport (18 players, 19 surgeries)
Results Twenty-three players (24 hips) underwent hip arthroscopy from January 2000 to December 2017 (Fig 1). The mean age was 27.5 3.1 years, and the mean experience in the NBA was 5.8 2.8 years at time of surgery. Seven hip surgeries (29.2%) were performed in the offseason. One player had bilateral surgery 3 years apart and returned to sport after both surgeries. There were no revision surgeries. Small forwards (n ¼ 8) represented the largest proportion of players that underwent hip arthroscopy (33.3%) (Table 1). There were no significant differences in demographic, performance, and games per season data between cases and matched controls presurgery and pre-index. Twenty players (21 hips, 87.5%) were able to RTS in NBA at an average of 5.7 2.6 months (Table 1). The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2% (Fig 2). Players in
Returned to sport, reƟred within 1 year (2 players, 2 surgeries)
Did not return to sport (3 players, 3 surgeries)
the control group (5.2 3.4 years) were in the NBA a similar number of years as (P ¼ .068) players who underwent hip arthroscopy (4.4 3.0 years). There was no significant decrease in games per season preoperatively compared with postoperatively and between postoperative cases and post-index controls (Tables 2 and 3). There was no significant decrease in PER/season for cases preoperatively compared with Table 1. Time to RTS by Position Position C PF SF SG PG Overall
n 4 4 8 1 7 24
RTS, % 75.0 100.0 75.0 100.0 100.0 87.5
Months to RTS 2.2 1.0 6.1 2.6 7.1 2.5 7.1 8.6 6.8 5.7 2.6
C, center; PF, power forward; PG, point guard; RTS, return to sport; SF, small forward; SG, shooting guard.
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R. A. JACK ET AL. 100% 90%
PERCENT SURVIVAL
80% 70% 60% 50% 40% 30% 20% 10% 0% 0
1
2
3
4
5
Cases
6 YEAR
7
8
9
10
11
12
13
Controls
Fig 2. KaplaneMeier survival analysis for cases and controls. Zero (0) signifies year of surgery for cases and index year for controls.
postoperatively (Table 3). There was no significant decrease in PER/season for cases postoperatively compared with controls post-index.
Discussion The study hypotheses were confirmed, with an 87.5% RTS rate for NBA players following hip arthroscopy. NBA athletes played similar games per season and career lengths postoperatively compared with preoperatively and matched controls. There was also no significant difference in performance compared with preoperatively and matched controls following surgery. The RTS rate in high-level basketball players has been previously reported to be 100% at an average of 2 to 3 months postoperatively.30,31 This is greater and faster than the current study, with a RTS rate of 87.5% at slightly less than 6 months. The lower RTS rate in the current study may be attributable to only including NBA players, whereas the other studies included high school and collegiate athletes. In addition, the definition of RTS is unclear in the previous studies, whereas the current study only considered a player to RTS if they played in an NBA regular season game following surgery with preseason and the developmental league not counting toward RTS. In the current study, only 5 NBA players were able to RTS in the same season as their surgery, and 78.9% of NBA players were in the
offseason during the recovery period of surgery. Therefore, the RTS time is likely inflated due to being in the offseason when the players were cleared to RTS. There are limited data regarding career length and games per season for NBA players undergoing hip arthroscopy. The overall 1-year NBA career survival rate of players undergoing hip arthroscopy was 79.2%, with no significant differences in career length and games per season between players undergoing hip arthroscopy and control players post-index. This same trend was seen in NFL players undergoing hip arthroscopy, with hip arthroscopy having no significant effect on career length and games per season following surgery compared with preoperatively and matched controls.13 Both cases and controls demonstrated a postoperative or post-index decline in games per season, respectively. However, there was no significant difference between the groups. This indicates that this may be a function of normal age-associated decline as opposed to a result of surgery. In addition, both the postoperative cases and postindex controls experienced a similar decline in performance compared with preoperative and pre-index levels. However, this decline was not statistically significant compared with preoperatively and compared with matched controls. These findings are similar to a recent study in NFL players following hip arthroscopy that found no significant performance differences postoperatively compared with matched controls.13 This is an incredibly important aspect of perioperative discussions with NBA players, teams, coaches, trainers, and basketball players aspiring to play in the NBA (developmental leagues, college, high school): following arthroscopic hip preservation surgery, players return with similar performance statistics compared with their preoperative levels and compared with matched controls. This study was not able to assess the outcomes of NBA players with FAI treated nonoperatively. The most common position undergoing hip arthroscopy was small forward (n ¼ 8, 33.3%) followed by point guard (n ¼ 7, 29.4%). The high prevalence is likely due to the repetitive high loading forces across the hip demanded by playing the positions. Small forward and point guard are typically filled by the most athletic players, requiring a significant amount of running and jumping.
Table 2. Statistics for Pre- and Postsurgery for Cases and Pre- and Post-Index for Controls Cases Statistic G/s PER/s
Preop 61.9 12.4 15.1 2.7
Postop 53.8 17.3 13.3 4.1
Controls P Value .045 .017
Pre-Index 65.7 9.3 15.4 2.9
Post-Index 62.1 15.1 14.0 3.8
NOTE. P value as determined by 2-tailed paired Student t test between pre- and postsurgery and pre- and post-index. G/s, games played per season; PER/s, player efficiency rating per season; postop, postoperative; preop, preoperative.
P Value .309 .115
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RTS AFTER HIP ARTHROSCOPY IN THE NBA Table 3. Postsurgery and Post-Index Statistics for Cases and Controls by Position Postsurgery and Post-index Statistic Seasons G/s PER/s
Cases 4.4 3.0 53.8 17.3 13.3 4.1
Controls 5.2 3.4 62.1 15.1 14.0 3.8
P Value .068 .145 .570
NOTE. P value as determined by 2-tailed paired Student t test. G/s, games played per season; PER/s, player efficiency rating per season.
Conversely, the center and power forward positions are more stationary, potentially leading to a decreased rate of FAI.7,10 Limitations There are limitations to this study and other studies of similar methodology. There is the potential for beta error, given comparisons without significant differences and the small number of subjects include in the study. This study also only evaluated male athletes in United Statesebased professional basketball only, so it may not translate to female athletes or other sports in other nations and has led to fewer subjects compared with other sports. Also, it is highly likely that surgeries performed in the early 2000s differed from more recent surgeries due to advancement in techniques and instrumentation. The use of publicly available data to identify players who underwent hip arthroscopy may be prone to selection, reporting, and observer bias. This is especially problematic with FAI and hip arthroscopy in general, as it is a relatively new diagnosis and the treatment has evolved significantly over the years. This differs compared with other, more common injuries such as anterior cruciate ligament tear, rotator cuff tear, and elbow ulnar collateral ligament tears, which have been diagnosed and treated much more commonly and routinely in the same time frame. However, this method of data acquisition has been used in multiple previous studies.20-23,25,26 By only including the highest level of professional players, these data may only apply to elite-level athletes. In addition, the PER may not provide a comprehensive evaluation of a player’s performance despite being used by several previous studies. Professional players have a greater rate of return to play than nonprofessional players.32 This is believed to be due to the inherently high talent and determination present at this level, with greater income potential and financial incentive to return.33 In addition, players may retire due to other nonperformancerelated reasons that are not able to be accounted for in this type of study. The authors may not have been able to identify all previous hip surgeries for the included players, which has been shown to have an effect on the outcomes of hip arthroscopy.34,35 Also,
career length and performance was not adjusted for “time missed” for players who underwent hip arthroscopy. Inherent to this type of study, there are multiple unknown confounding variables such no direct physical contact, patient-reported outcomes, or medical records access to corroborate diagnosis and treatment. The use of public data limits the ability to determine the chronicity and severity of the injury. It was also unable to be determined reliably the surgeon who performed the operation or exact operative procedure used in each hip arthroscopy (labral debridement vs repair vs reconstruction, degree of cam/pincer correction/undercorrection/overcorrection, chondral treatments for variable degrees of articular cartilage pathology/ arthritis, or capsular closure/repair/plication/shift; periarticular extra-articular peritrochanteric, deep gluteal space, or athletic pubalgia/core muscle injury). Heterogeneity of surgeons or surgeon experience is also a limitation. Other limitations include the absence of patient-reported outcomes and incomplete follow-up and career length for players still in their respective leagues. It is also possible that by performing a Bonferroni correction, the present study could miss a difference that does exist.
Conclusions The RTS rate for NBA athletes after hip arthroscopy is high. There was no decrease in games played, career lengths, or performance following hip arthroscopy in NBA players versus preoperatively and matched controls.
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