XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
Scott Med J OnlineFirst, published on November 26, 2014 as doi:10.1177/0036933014560300
Original Article
Clinical outcome scores for arthroscopic femoral osteochondroplasty in femoroacetabular impingement: a quantitative systematic review
Scottish Medical Journal 0(0) 1–10 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0036933014560300 scm.sagepub.com
JA Gillespie1, SR Patil2 and RDM Meek2
Abstract Background and aims: Femoroacetabular impingement is the abnormal contact of the proximal femur and acetabulum during motion. It causes hip pain and joint degeneration in young patients. This systematic review aims to clarify the clinical effect of arthroscopic femoral osteochondroplasty for cam lesions and to review the available literature for the general medical readership, including providers of primary and secondary care. Methods and results: Electronic databases were searched for studies of arthroscopic femoral osteochondroplasty in primary femoroacetabular impingement. A total of 2618 article titles, 242 abstracts and 33 full text articles were considered. Ultimately nine studies with clinical outcome scores met the inclusion criteria and were included in the qualitative systematic review. Six studies were suitable for meta-analysis using an inverse variance, random effects model (RevMan software). In the nine studies, improvements were seen in Western Ontario and McMaster Universities Osteoarthritis index, Nonarthritic Hip Score and Modified Harris Hip Scores. Across the six studies suitable for meta-analysis (537 patients), a 24point weighted mean improvement in Non-arthritic hip score was seen. This yielded a large overall effect size of 1.6. Conclusion: Arthroscopic femoral osteochondroplasty appears to be a beneficial treatment for primary femoroacetabular impingement, with a large effect size seen across six eligible studies.
Keywords Arthroscopy, osteochondroplasty, femoroplasty, femoroacetabular, hip
Introduction Primary femoroacetabular impingement (FAI) was described by Ganz as a cause of hip pain and osteoarthritis.1 It results from abnormal contact/impingement of the femoral neck and acetabular rim. This reduced joint clearance can be a consequence of increased nonsphericity of the femoral head–neck junction (cam) and/or acetabular over-coverage (pincer).1,2 These are described by alpha angle of 55 (cam lesion)3–5 and a centre edge angel 40 (acetabular over-coverage, i.e. pincer impingement).6 These pathologies can be combined (mixed FAI). Early reports from a prospective cohort suggest that cam deformity is associated with a significant increase in the risk of end stage osteoarthritis (OA) at 5 years.7
Symptoms of the FAI include groin pain associated with sporting activity and prolonged or repetitive hip flexion.1,2 The clinical impingement sign involves the elicitation of groin/hip pain from forceful flexion and internal rotation of the hip.8 Conservative measures can be trialled, e.g. non-steroidal anti-inflammatory drugs and activity modification, but these may mask the underlying joint destruction.2 1 2
Orthopaedic Registrar, Southern General Hospital, UK Consultant Orthopaedic Surgeon, Southern General Hospital, UK
Corresponding author: JA Gillespie, Southern General Hospital, Glasgow G51 4TF, United Kingdom. Email: [email protected]
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
2
Scottish Medical Journal 0(0)
Before the advent of arthroscopic osteochondroplasty of the hip, Ganz pioneered the use of surgical dislocation via a trochanteric osteotomy to facilitate adequate, safe exposure of the hip joint in treatment of FAI and other disorders.9 Due to the trochanteric osteotomy patients’ flexion and weight-bearing status must be restricted for up to eight weeks to allow the osteotomy to heal.2 This type of surgery has shown improvements in the Merle d’Aubigne Hip Score,10 Harris Hip Score11 and in both the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and short-form 12.12 There was subsequent interest in the use of therapeutic hip arthroscopy. Stahelin et al.13 described resection of the head–neck junction using a high speed burr until no femoroacetabular contact was visible in 110 flexion, 20 internal rotation and 20 adduction. To avoid fracture, it is suggested that not greater than 20% of the neck diameter is resected based on cadaveric biomechanical studies.14 Various clinical outcome scores are described in the literature and are summarised in Table 1.
Aim and clinical importance of the project A critical review of the literature was performed followed by analysis of preoperative and postoperative clinical outcome scores. The hypothesis was that arthroscopic femoral osteochondroplasty for cam lesions resulted in an improvement in clinical outcome scores.23
Methods Search process and article selection Electronic database and hand searches were performed in March 2013. Medline and EMBASE databases were
interrogated. Since FAI was first described in 1999,24 the search was confined to 1999 to March 2013. The following short search strings on the title and abstract: ‘femoroacetabular’; ‘femoro-acetabular’; ‘hip AND impingement’; ‘hip AND debridement’; ‘hip AND arthroscop$’ (where $ is a wildcard); ‘hip AND (osteochondroplasty OR osteoplasty)’; ‘femoroplasty’; ‘cam AND impingement’; ‘pincer AND impingement’. Each search string’s results was added to the project workspace on OVID. This simultaneous search within OVID allows an initial deduplication of articles with the same unique identifier. PUBMED was interrogated for citations using the equivalent search strategies, specifically looking for articles which are not from Medline. Furthermore, The Cochrane Central Register of Controlled Trials was also searched for trials not indexed in the aforementioned databases.25 To compensate for the lag time from publication to database indexing, a hand search of the table of contents of relevant journals covered the period October 2012–March 2013. Potentially relevant journals were: (1) American Journal of Sports Medicine, (2) British Journal of Sports Medicine, (3) Clinical Orthopaedic Related Research, (4) Journal of Bone and Joint Surgery (Am), (5) Bone and Joint Journal, (6) Operative Techniques in Orthopaedics, (7) Arthroscopy, (8) Hip international, (9) Journal of Arthroplasty, (10) Techniques in Orthopaedics, (11) Orthopaedics & Traumatology: Surgery and Research. Citations were imported into Zotero reference manager (version 3.0.14) and an initial screening of article titles was made. Thereafter, potential studies were identified for further abstract review with suitable articles undergoing subsequent full text review. Inclusion criteria: . Studies concern skeletally mature patients with primary FAI;
Table 1. Scoring systems in the literature. Scoring System
Intended Use
Relevance in hip arthroscopy
Modified Harris Hip Score (MHHS)
Modification of the original Harris Hip Score to remove the clinical examination component. Primarily designed for osteoarthritis Designed for and validated for use in osteoarthritis of the hip hip/knee18–20
Validated in hip arthroscopy.15 Correlates with patient satisfaction in hip arthroscopy16 and SF-3617 Not validated in hip arthroscopy. Considered an imperfect tool21
A modification of the WOMAC which has been validated in 20–40-year-old patients, with normal radiographs
Correlates with Harris Hip Score and SF-1222
Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) Non-arthritic hip score (NAHS)
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
Gillespie et al.
3
. Cam/mixed impingement undergoing arthroscopic femoral osteochondroplasty procedure; . Minimum six months follow-up; . Peer reviewed journals; . Levels of evidence 1–4;26 . Have pre and postoperative clinical outcome scores. Exclusion criteria: Skeletally immature patients; Secondary FAI (e.g. hip dysplasia); Revision surgery; Small case series < 10 patients; Conference proceeding abstracts; Duplicate/overlapping cohorts – the most recent will be used; . Review articles/ systematic reviews / meta-analysis / cadaveric studies. . . . . . .
Figure 1 demonstrates the selection process according to the template recommended by Preferred Reporting Items for Systematic Reviews and MetaAnalyses.
Data extraction Details extracted include study design; population/age; timeframe for recruitment; inclusion criteria; surgical procedures performed; follow-up time; loss-to-followup rate, preoperative and postoperative clinical outcome scores and where applicable the p value for the difference; definition and rates of failure, e.g. conversion to total hip replacement (THR), revision surgery and complications. An overview is presented to establish similarities and attempt to draw wider statistical conclusions, i.e. meta-analysis.
Figure 1. Article selection process.
Results Statistical analysis Where possible, for each study, RevMan27 was used to calculate the absolute mean change in clinical outcome scores and standardised mean difference (effect size).28 The Non-Arthritic Hip Score (NAHS) was used across multiple studies. Due to the heterogeneity of the studies, a Random Effects (inverse variance) model was used to calculate the weighted mean change in NAHS and overall effect size.29 An effect size of >0.8 is generally considered large.30 Some studies do not describe the SD in the mean clinical outcome score. The authors were contacted to request these, but at this time some data were not available. Assuming an approximate normal distribution of data, the SD can be estimated for Cochrane Reviews and other meta-analysis using the method described by Walter and Yao.31
The data were extracted from the individual studies tabulated to facilitate comparison of study design and patient population (Table 2). The individual study results are combined in Table 3 along with the absolute ‘change in mean’ and the ‘effect size’ and indeed an explanation for those studies which will not be included in the meta-analysis. The meta-analysis (weighted mean change and effect size) has been performed twice. Table 4 includes the non-parametric data of Palmer et al.38 and Stahelin et al.13 (mean change in NAHS 24.1 and effect size 1.6) and then repeated excluding these two studies yielding a mean change in NAHS of 24.6 and an effect size of 1.7 (this separate calculation has not been tabulated). Using the data from all NAHS studies, a forest plot with each study’s mean change in NAHS,
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
Prospective case series (comparative)
Prospective case series
Prospective case series
Retrospective case series 170
Prospective case series
Retrospective case series 40
Prospective case series
Prospective case series
Brunner et al.33 (2009)
Brunner et al.34 (2009)
Byrd and Jones35 (2009)
Haviv et al.36 (2010)
Ilizaliturri et al.21 (2008)
Javed and O’Donnell37 (2011)
Palmeret al.38 (2012)
Stahelin et al.13 (2008)
31 cam/22 mixed
40 cam
18 cam
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
23 cam
29
27
12
42 (18–67)
40 (14–87)
65 (60–82)
34 (27–43)
37 (14–78)
6
46
30
24
22
33 (range n/a) 16
42 (17–66)
43 (17–67)
33 (27–41)
RA, Perthes, dysplasia, previous surgery, To¨nnis grade 2 and above To¨nnis grade 3, previous surgery
To¨nnis grade 3
Bone-on-bone contact
OB grade: 2 (n ¼ 35), 3(n ¼ 83), 4 (n ¼ 52)
OB grade: 0–2 (n ¼ 17), 3 (n ¼ 83), 4 (n ¼ 107); 45% were athletes
To¨nnis grade: 0(n ¼ 8), 1 (n ¼ 32), 2 (n ¼ 13)
All were To¨nnis 0 or 1
Other noteworthy comments
Dysplasia/SCFE/paediatric disease Failure of six months To¨nnis grade 2 and above, All were To¨nnis 0 or 1 non-operative bilateral disease, management. >60 Perthes, dysplasia, years of age, pure previous surgery cam FAI Cam/mixed FAI, To¨nnis grade 3, dysplasia, OB grade +impingement sign synovitis, >1.5 cm 0–3 (n ¼ 156), chondral lesions 4 (n ¼ 45); To¨nnis grade: 0 (n ¼ 174), 1 (n ¼ 25), 2 (n ¼ 1) Symptomatic, pure Previous surgery, To¨nnis To¨nnis grade: cam FAI Grade 3 0(n ¼ 15), 1 (n ¼ 5), 2 (n ¼ 3)
Pure cam FAI
Failure of 12 months non-operative treatment, + impingement sign,
Cam/mixed FAI
Cam/mixed FAI, To¨nnis grade 3, previous +impingement sign surgery, RA, other MSK disease
Pure cam FAI, alpha >50 , +impingement sign
Pure cam FAI
Exclusion criteria
Total patients (some may be bilateral). FAI: femoroacetabular impingement; MSK: musculoskeletal; OB: outerbridge cartilage grading; RA: rheumatoid arthritis; SCFE: slipped capital femoral epiphysis.
15 M: 7 F (22)
99 M: 102 F (201) 152 cam/49 mixed
26 M: 14 F (40)
10 M: 8 F (18)
132 M: 34 F (166) 170 cam
138 M: 62 F (200) 163 cam/44 mixed
41 M: 12 F (53)
50 cam
24 cam
Type of FAI
Mean follow-up (months) Inclusion criteria
4
23
201
18
207
53
39 M: 11 F (50)
14 M: 10 F (24)
Gender (total)a
Mean age (range)
(SCM)
a
Retrospective case series 24 (historical control)
Bardakos et al.32 (2008)
25 (nonnavigated) 25 (navigated)
Study Type
Author (year) and reference
Number of hips (subgroup)
Table 2. Study design and patient population.
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d [1–10] [INVALID Stage]
Scottish Medical Journal 0(0)
NAHS
Havivet al.36 (2010)
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
NAHS
Stahelin et al.13 (2008) 23
201
SD
14.47¥
85.7
89.5
81.9
11.92¥
10.16¥
13.34¥
60.5
62.1
82
70.7
69.8
19.6
15.9
16.25
13.24
9
16.6
16.4
74
78.2
79.7
77.2
89
86.1
84.8
19.5
15.8
16.18
15.4
9
16.2
16.3
Described a mean score change of 20 but does not give pre and post op scores
54.4
13.34¥
56.6
100% femoral OCP labral 56.1 debridement# Labral repair (n ¼ 11) Acetabular rim resection (n ¼ 46) 100% femoral OCP Labral 49.5 debridement (n ¼ 21) Labral repair (n ¼ 2)
100% femoral OCP Labral debridement (n ¼ 15)
100% femoral OCP Labral debridement (n ¼ 15) Ligamentum teres debridement (n ¼ 11)
100% femoral OCP chondral procedure# Microfracture (n ¼ 29)
100% femoral OCP ‘correction of pincer’ (n ¼ 44) Microfracture (n ¼ 58)
100% femoral OCP Labral debridement (n ¼ 41) Acetabular rim trimming (n ¼ 22)
18.72¥
51.9
SD
Median 83 IQ range 75–87
Mean
Post Op Score Change in Mean (95% CI)
15.10 (8.81, 21.39)
1.04 (0.57, 1.51)
0.76 (0.08, 1.14)
15.40 (11.91, 18.89) 0.94 (0.71, 1.16)
15.00 (11.52, 18.48) 0.92 (0.69, 1.14)
Insufficient data
31.30 (26.25, 36.35) 2.34 (1.85, 2.84)
32.90 (26.33, 39.47) 2.73 (1.95, 3.52)
Wilcoxon Signed Rank p < 0.05
24.50 (13.20, 35.80) 1.23 (0.60, 1.87)
Paired t-test 19.20 (12.09, 26.31) 1.17 (0.70, 1.65) p < 0.001 Wilcoxon Signed 22.10 (19.00, 25.20) 1.39 (1.17, 1.61) Rank p < 0.001
Paired t-test p < 0.001
Effect Size (95% CI)
30.00 (20.99, 39.01) 1.82 (1.15, 2.48)
Wilcoxon Signed 7.00 (1.12, 12.88) Rank p ¼ 0.001
Paired t-test p < 0.001
Paired t-test p < 0.001
No statistical tests
Paired t-test p < 0.001
Paired t-test p < 0.001
Paired t-test p < 0.001
Wilcoxon Signed Insufficient data Rank p < 0.001
Statistical Test and significance of change
Y (cautious of skew)
Y (cautious of skew)
Y
N (WOMAC not validated in hip arthroscopy)
Y
N (insufficient data)
Y
Y
N (cannot use medians and IQ ranges)
Include in metaanalysis (Y/N)
IQ: range interquartile range for non-parametric data; MHHS; Modified Harris Hip Score (0–100); N: no; NAHS; Non-arthritic Hip Score (0-100); OCP: osteochondroplasty; #: number of procedures not detailed; SD: standard deviation; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index (0–96); Y: yes; ¥: calculated using method described by Walter and Yao (see ‘Methods’ section).
NAHS
Palmer et al.38 (2012)
MHHS
40
NAHS
Javed and O’Donnell (2011)
37
18
WOMAC
Ilizaliturri et al.21 (2008)
170
207
53
Mean
Pre op Score
100% femoral OCP labral Median 59 IQ debridement# chondral range 52–64 procedure# microfracture#
Arthroscopic Procedures
25 (Non100% femoral OCP Labral navigated) debridement (n ¼ 39) 25 (navigated) Microfracture (n ¼ 20)
24
Number of hips (subgroup)
(SCM)
MHHS
MHHS
Byrd and Jones35 (2009)
NAHS
Brunner et al.33 (2009)
NAHS
MHHS
Bardakos et al.32 (2008)
Brunner et al.34 (2009)
Scoring System
Author (year) and reference
Table 3. Results for individual studies.
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d [1–10] [INVALID Stage]
Gillespie et al. 5
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
6
Scottish Medical Journal 0(0)
Table 4. Meta-analysis including studies by Palmer and Stahelin. Pre op NAHS
Post Op NAHS
Mean
SD
Mean
SD
Weighta (IV random Change in effects) Mean (95% CI)
25 (Non-navigated) 51.9 25 (Navigated) 56.6 53 54.4
18.72¥ 13.34¥ 14.47¥
81.9 89.5 85.7
13.34¥ 10.16¥ 11.92¥
12.4% 11.1% 14.4%
30.00 (20.99, 39.01) 1.82 (1.15, 2.48) 32.90 (26.33, 39.47) 2.73 (1.95, 3.52) 31.30 (26.25, 36.35) 2.34 (1.85, 2.84)
170 40
69.8 62.1
16.4 13.24
84.8 77.2
16.3 15.4
17.2% 14.8%
15.00 (11.52, 18.48) 0.92 (0.69, 1.14) 15.10 (8.81, 21.39) 1.04 (0.57, 1.51)
201
56.1
15.9
78.2
15.8
17.3%
22.10 (19.00, 25.20) 1.39 (1.17, 1.61)
23
49.5
19.6
74
19.5
12.8%
24.50 (13.20, 35.80) 1.23 (0.60, 1.87)
Author (year) and reference
Number of hips (subgroup)
Brunner et al.33 (2009) Brunner et al.34 (2009) Haviv et al.36 (2010) Javed and O’Donnell37 (2011) Palmer et al.38 (2012) Stahelin et al.13 (2008) Total Weighted mean statistical analysis: Overall size of effect statistical analysis:
Effect Size (95% CI)
537 100% 24.09 (18.42, 29.76) 1.58 (1.16, 2.00) Heterogeneity: Tau2 ¼ 47.52; Chi2 ¼ 47.03, df ¼ 6 (P < 0.00001); I2 ¼ 87% Test for overall effect: Z ¼ 8.32 (P < 0.00001) Heterogeneity: Tau2 ¼ 0.25; Chi2 ¼ 45.14, df ¼ 6 (P < 0.00001); I2 ¼ 87% Test for overall effect: Z ¼ 7.34 (P < 0.00001)
a Weight is illustrated for weighted mean rather than effect size. df: degrees of freedom; IV: inverse variance; NAHS: Non-arthritic Hip Score (0–100); SD: standard deviation; ¥: calculated using method described by Walter and Yao (see ‘Methods’ section).
95% confidence interval and the overall weighted mean change is shown in Figure 2.
Discussion There were no randomised controlled trials which met the inclusion criteria that compared non-operative and operative treatments. Three studies were retrospective,32,36,37 while six were prospective.13,21,33–35,38 One of the papers by Brunner compared computer navigated with conventional arthroscopic surgery33 but no clinical advantage was noted with navigation. The NAHS was the most common outcome measure used in six studies,13,33,34,36–38 the Modified Harris Hip Score (MHHS) was used in four32,35–37 and WOMAC in one.21 All nine studies reported improvements in the clinical outcome scores used, and those that reported complication rates described these as being low. Variable definitions of failure were used, including decreased clinical outcome score, conversion to THR and revision surgery. Where complications were discussed, generally a
(SCM)
[1–10] [INVALID Stage]
Scott Med J OnlineFirst, published on November 26, 2014 as doi:10.1177/0036933014560300
Original Article
Clinical outcome scores for arthroscopic femoral osteochondroplasty in femoroacetabular impingement: a quantitative systematic review
Scottish Medical Journal 0(0) 1–10 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0036933014560300 scm.sagepub.com
JA Gillespie1, SR Patil2 and RDM Meek2
Abstract Background and aims: Femoroacetabular impingement is the abnormal contact of the proximal femur and acetabulum during motion. It causes hip pain and joint degeneration in young patients. This systematic review aims to clarify the clinical effect of arthroscopic femoral osteochondroplasty for cam lesions and to review the available literature for the general medical readership, including providers of primary and secondary care. Methods and results: Electronic databases were searched for studies of arthroscopic femoral osteochondroplasty in primary femoroacetabular impingement. A total of 2618 article titles, 242 abstracts and 33 full text articles were considered. Ultimately nine studies with clinical outcome scores met the inclusion criteria and were included in the qualitative systematic review. Six studies were suitable for meta-analysis using an inverse variance, random effects model (RevMan software). In the nine studies, improvements were seen in Western Ontario and McMaster Universities Osteoarthritis index, Nonarthritic Hip Score and Modified Harris Hip Scores. Across the six studies suitable for meta-analysis (537 patients), a 24point weighted mean improvement in Non-arthritic hip score was seen. This yielded a large overall effect size of 1.6. Conclusion: Arthroscopic femoral osteochondroplasty appears to be a beneficial treatment for primary femoroacetabular impingement, with a large effect size seen across six eligible studies.
Keywords Arthroscopy, osteochondroplasty, femoroplasty, femoroacetabular, hip
Introduction Primary femoroacetabular impingement (FAI) was described by Ganz as a cause of hip pain and osteoarthritis.1 It results from abnormal contact/impingement of the femoral neck and acetabular rim. This reduced joint clearance can be a consequence of increased nonsphericity of the femoral head–neck junction (cam) and/or acetabular over-coverage (pincer).1,2 These are described by alpha angle of 55 (cam lesion)3–5 and a centre edge angel 40 (acetabular over-coverage, i.e. pincer impingement).6 These pathologies can be combined (mixed FAI). Early reports from a prospective cohort suggest that cam deformity is associated with a significant increase in the risk of end stage osteoarthritis (OA) at 5 years.7
Symptoms of the FAI include groin pain associated with sporting activity and prolonged or repetitive hip flexion.1,2 The clinical impingement sign involves the elicitation of groin/hip pain from forceful flexion and internal rotation of the hip.8 Conservative measures can be trialled, e.g. non-steroidal anti-inflammatory drugs and activity modification, but these may mask the underlying joint destruction.2 1 2
Orthopaedic Registrar, Southern General Hospital, UK Consultant Orthopaedic Surgeon, Southern General Hospital, UK
Corresponding author: JA Gillespie, Southern General Hospital, Glasgow G51 4TF, United Kingdom. Email: [email protected]
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
2
Scottish Medical Journal 0(0)
Before the advent of arthroscopic osteochondroplasty of the hip, Ganz pioneered the use of surgical dislocation via a trochanteric osteotomy to facilitate adequate, safe exposure of the hip joint in treatment of FAI and other disorders.9 Due to the trochanteric osteotomy patients’ flexion and weight-bearing status must be restricted for up to eight weeks to allow the osteotomy to heal.2 This type of surgery has shown improvements in the Merle d’Aubigne Hip Score,10 Harris Hip Score11 and in both the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and short-form 12.12 There was subsequent interest in the use of therapeutic hip arthroscopy. Stahelin et al.13 described resection of the head–neck junction using a high speed burr until no femoroacetabular contact was visible in 110 flexion, 20 internal rotation and 20 adduction. To avoid fracture, it is suggested that not greater than 20% of the neck diameter is resected based on cadaveric biomechanical studies.14 Various clinical outcome scores are described in the literature and are summarised in Table 1.
Aim and clinical importance of the project A critical review of the literature was performed followed by analysis of preoperative and postoperative clinical outcome scores. The hypothesis was that arthroscopic femoral osteochondroplasty for cam lesions resulted in an improvement in clinical outcome scores.23
Methods Search process and article selection Electronic database and hand searches were performed in March 2013. Medline and EMBASE databases were
interrogated. Since FAI was first described in 1999,24 the search was confined to 1999 to March 2013. The following short search strings on the title and abstract: ‘femoroacetabular’; ‘femoro-acetabular’; ‘hip AND impingement’; ‘hip AND debridement’; ‘hip AND arthroscop$’ (where $ is a wildcard); ‘hip AND (osteochondroplasty OR osteoplasty)’; ‘femoroplasty’; ‘cam AND impingement’; ‘pincer AND impingement’. Each search string’s results was added to the project workspace on OVID. This simultaneous search within OVID allows an initial deduplication of articles with the same unique identifier. PUBMED was interrogated for citations using the equivalent search strategies, specifically looking for articles which are not from Medline. Furthermore, The Cochrane Central Register of Controlled Trials was also searched for trials not indexed in the aforementioned databases.25 To compensate for the lag time from publication to database indexing, a hand search of the table of contents of relevant journals covered the period October 2012–March 2013. Potentially relevant journals were: (1) American Journal of Sports Medicine, (2) British Journal of Sports Medicine, (3) Clinical Orthopaedic Related Research, (4) Journal of Bone and Joint Surgery (Am), (5) Bone and Joint Journal, (6) Operative Techniques in Orthopaedics, (7) Arthroscopy, (8) Hip international, (9) Journal of Arthroplasty, (10) Techniques in Orthopaedics, (11) Orthopaedics & Traumatology: Surgery and Research. Citations were imported into Zotero reference manager (version 3.0.14) and an initial screening of article titles was made. Thereafter, potential studies were identified for further abstract review with suitable articles undergoing subsequent full text review. Inclusion criteria: . Studies concern skeletally mature patients with primary FAI;
Table 1. Scoring systems in the literature. Scoring System
Intended Use
Relevance in hip arthroscopy
Modified Harris Hip Score (MHHS)
Modification of the original Harris Hip Score to remove the clinical examination component. Primarily designed for osteoarthritis Designed for and validated for use in osteoarthritis of the hip hip/knee18–20
Validated in hip arthroscopy.15 Correlates with patient satisfaction in hip arthroscopy16 and SF-3617 Not validated in hip arthroscopy. Considered an imperfect tool21
A modification of the WOMAC which has been validated in 20–40-year-old patients, with normal radiographs
Correlates with Harris Hip Score and SF-1222
Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) Non-arthritic hip score (NAHS)
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
Gillespie et al.
3
. Cam/mixed impingement undergoing arthroscopic femoral osteochondroplasty procedure; . Minimum six months follow-up; . Peer reviewed journals; . Levels of evidence 1–4;26 . Have pre and postoperative clinical outcome scores. Exclusion criteria: Skeletally immature patients; Secondary FAI (e.g. hip dysplasia); Revision surgery; Small case series < 10 patients; Conference proceeding abstracts; Duplicate/overlapping cohorts – the most recent will be used; . Review articles/ systematic reviews / meta-analysis / cadaveric studies. . . . . . .
Figure 1 demonstrates the selection process according to the template recommended by Preferred Reporting Items for Systematic Reviews and MetaAnalyses.
Data extraction Details extracted include study design; population/age; timeframe for recruitment; inclusion criteria; surgical procedures performed; follow-up time; loss-to-followup rate, preoperative and postoperative clinical outcome scores and where applicable the p value for the difference; definition and rates of failure, e.g. conversion to total hip replacement (THR), revision surgery and complications. An overview is presented to establish similarities and attempt to draw wider statistical conclusions, i.e. meta-analysis.
Figure 1. Article selection process.
Results Statistical analysis Where possible, for each study, RevMan27 was used to calculate the absolute mean change in clinical outcome scores and standardised mean difference (effect size).28 The Non-Arthritic Hip Score (NAHS) was used across multiple studies. Due to the heterogeneity of the studies, a Random Effects (inverse variance) model was used to calculate the weighted mean change in NAHS and overall effect size.29 An effect size of >0.8 is generally considered large.30 Some studies do not describe the SD in the mean clinical outcome score. The authors were contacted to request these, but at this time some data were not available. Assuming an approximate normal distribution of data, the SD can be estimated for Cochrane Reviews and other meta-analysis using the method described by Walter and Yao.31
The data were extracted from the individual studies tabulated to facilitate comparison of study design and patient population (Table 2). The individual study results are combined in Table 3 along with the absolute ‘change in mean’ and the ‘effect size’ and indeed an explanation for those studies which will not be included in the meta-analysis. The meta-analysis (weighted mean change and effect size) has been performed twice. Table 4 includes the non-parametric data of Palmer et al.38 and Stahelin et al.13 (mean change in NAHS 24.1 and effect size 1.6) and then repeated excluding these two studies yielding a mean change in NAHS of 24.6 and an effect size of 1.7 (this separate calculation has not been tabulated). Using the data from all NAHS studies, a forest plot with each study’s mean change in NAHS,
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
Prospective case series (comparative)
Prospective case series
Prospective case series
Retrospective case series 170
Prospective case series
Retrospective case series 40
Prospective case series
Prospective case series
Brunner et al.33 (2009)
Brunner et al.34 (2009)
Byrd and Jones35 (2009)
Haviv et al.36 (2010)
Ilizaliturri et al.21 (2008)
Javed and O’Donnell37 (2011)
Palmeret al.38 (2012)
Stahelin et al.13 (2008)
31 cam/22 mixed
40 cam
18 cam
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
23 cam
29
27
12
42 (18–67)
40 (14–87)
65 (60–82)
34 (27–43)
37 (14–78)
6
46
30
24
22
33 (range n/a) 16
42 (17–66)
43 (17–67)
33 (27–41)
RA, Perthes, dysplasia, previous surgery, To¨nnis grade 2 and above To¨nnis grade 3, previous surgery
To¨nnis grade 3
Bone-on-bone contact
OB grade: 2 (n ¼ 35), 3(n ¼ 83), 4 (n ¼ 52)
OB grade: 0–2 (n ¼ 17), 3 (n ¼ 83), 4 (n ¼ 107); 45% were athletes
To¨nnis grade: 0(n ¼ 8), 1 (n ¼ 32), 2 (n ¼ 13)
All were To¨nnis 0 or 1
Other noteworthy comments
Dysplasia/SCFE/paediatric disease Failure of six months To¨nnis grade 2 and above, All were To¨nnis 0 or 1 non-operative bilateral disease, management. >60 Perthes, dysplasia, years of age, pure previous surgery cam FAI Cam/mixed FAI, To¨nnis grade 3, dysplasia, OB grade +impingement sign synovitis, >1.5 cm 0–3 (n ¼ 156), chondral lesions 4 (n ¼ 45); To¨nnis grade: 0 (n ¼ 174), 1 (n ¼ 25), 2 (n ¼ 1) Symptomatic, pure Previous surgery, To¨nnis To¨nnis grade: cam FAI Grade 3 0(n ¼ 15), 1 (n ¼ 5), 2 (n ¼ 3)
Pure cam FAI
Failure of 12 months non-operative treatment, + impingement sign,
Cam/mixed FAI
Cam/mixed FAI, To¨nnis grade 3, previous +impingement sign surgery, RA, other MSK disease
Pure cam FAI, alpha >50 , +impingement sign
Pure cam FAI
Exclusion criteria
Total patients (some may be bilateral). FAI: femoroacetabular impingement; MSK: musculoskeletal; OB: outerbridge cartilage grading; RA: rheumatoid arthritis; SCFE: slipped capital femoral epiphysis.
15 M: 7 F (22)
99 M: 102 F (201) 152 cam/49 mixed
26 M: 14 F (40)
10 M: 8 F (18)
132 M: 34 F (166) 170 cam
138 M: 62 F (200) 163 cam/44 mixed
41 M: 12 F (53)
50 cam
24 cam
Type of FAI
Mean follow-up (months) Inclusion criteria
4
23
201
18
207
53
39 M: 11 F (50)
14 M: 10 F (24)
Gender (total)a
Mean age (range)
(SCM)
a
Retrospective case series 24 (historical control)
Bardakos et al.32 (2008)
25 (nonnavigated) 25 (navigated)
Study Type
Author (year) and reference
Number of hips (subgroup)
Table 2. Study design and patient population.
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d [1–10] [INVALID Stage]
Scottish Medical Journal 0(0)
NAHS
Havivet al.36 (2010)
Downloaded from scm.sagepub.com at WASHINGTON UNIV SCHL OF MED on January 17, 2015
NAHS
Stahelin et al.13 (2008) 23
201
SD
14.47¥
85.7
89.5
81.9
11.92¥
10.16¥
13.34¥
60.5
62.1
82
70.7
69.8
19.6
15.9
16.25
13.24
9
16.6
16.4
74
78.2
79.7
77.2
89
86.1
84.8
19.5
15.8
16.18
15.4
9
16.2
16.3
Described a mean score change of 20 but does not give pre and post op scores
54.4
13.34¥
56.6
100% femoral OCP labral 56.1 debridement# Labral repair (n ¼ 11) Acetabular rim resection (n ¼ 46) 100% femoral OCP Labral 49.5 debridement (n ¼ 21) Labral repair (n ¼ 2)
100% femoral OCP Labral debridement (n ¼ 15)
100% femoral OCP Labral debridement (n ¼ 15) Ligamentum teres debridement (n ¼ 11)
100% femoral OCP chondral procedure# Microfracture (n ¼ 29)
100% femoral OCP ‘correction of pincer’ (n ¼ 44) Microfracture (n ¼ 58)
100% femoral OCP Labral debridement (n ¼ 41) Acetabular rim trimming (n ¼ 22)
18.72¥
51.9
SD
Median 83 IQ range 75–87
Mean
Post Op Score Change in Mean (95% CI)
15.10 (8.81, 21.39)
1.04 (0.57, 1.51)
0.76 (0.08, 1.14)
15.40 (11.91, 18.89) 0.94 (0.71, 1.16)
15.00 (11.52, 18.48) 0.92 (0.69, 1.14)
Insufficient data
31.30 (26.25, 36.35) 2.34 (1.85, 2.84)
32.90 (26.33, 39.47) 2.73 (1.95, 3.52)
Wilcoxon Signed Rank p < 0.05
24.50 (13.20, 35.80) 1.23 (0.60, 1.87)
Paired t-test 19.20 (12.09, 26.31) 1.17 (0.70, 1.65) p < 0.001 Wilcoxon Signed 22.10 (19.00, 25.20) 1.39 (1.17, 1.61) Rank p < 0.001
Paired t-test p < 0.001
Effect Size (95% CI)
30.00 (20.99, 39.01) 1.82 (1.15, 2.48)
Wilcoxon Signed 7.00 (1.12, 12.88) Rank p ¼ 0.001
Paired t-test p < 0.001
Paired t-test p < 0.001
No statistical tests
Paired t-test p < 0.001
Paired t-test p < 0.001
Paired t-test p < 0.001
Wilcoxon Signed Insufficient data Rank p < 0.001
Statistical Test and significance of change
Y (cautious of skew)
Y (cautious of skew)
Y
N (WOMAC not validated in hip arthroscopy)
Y
N (insufficient data)
Y
Y
N (cannot use medians and IQ ranges)
Include in metaanalysis (Y/N)
IQ: range interquartile range for non-parametric data; MHHS; Modified Harris Hip Score (0–100); N: no; NAHS; Non-arthritic Hip Score (0-100); OCP: osteochondroplasty; #: number of procedures not detailed; SD: standard deviation; WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index (0–96); Y: yes; ¥: calculated using method described by Walter and Yao (see ‘Methods’ section).
NAHS
Palmer et al.38 (2012)
MHHS
40
NAHS
Javed and O’Donnell (2011)
37
18
WOMAC
Ilizaliturri et al.21 (2008)
170
207
53
Mean
Pre op Score
100% femoral OCP labral Median 59 IQ debridement# chondral range 52–64 procedure# microfracture#
Arthroscopic Procedures
25 (Non100% femoral OCP Labral navigated) debridement (n ¼ 39) 25 (navigated) Microfracture (n ¼ 20)
24
Number of hips (subgroup)
(SCM)
MHHS
MHHS
Byrd and Jones35 (2009)
NAHS
Brunner et al.33 (2009)
NAHS
MHHS
Bardakos et al.32 (2008)
Brunner et al.34 (2009)
Scoring System
Author (year) and reference
Table 3. Results for individual studies.
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d [1–10] [INVALID Stage]
Gillespie et al. 5
XML Template (2014) [21.11.2014–12:50pm] //blrnas3.glyph.com/cenpro/ApplicationFiles/Journals/SAGE/3B2/SCMJ/Vol00000/140066/APPFile/SG-SCMJ140066.3d
(SCM)
[1–10] [INVALID Stage]
6
Scottish Medical Journal 0(0)
Table 4. Meta-analysis including studies by Palmer and Stahelin. Pre op NAHS
Post Op NAHS
Mean
SD
Mean
SD
Weighta (IV random Change in effects) Mean (95% CI)
25 (Non-navigated) 51.9 25 (Navigated) 56.6 53 54.4
18.72¥ 13.34¥ 14.47¥
81.9 89.5 85.7
13.34¥ 10.16¥ 11.92¥
12.4% 11.1% 14.4%
30.00 (20.99, 39.01) 1.82 (1.15, 2.48) 32.90 (26.33, 39.47) 2.73 (1.95, 3.52) 31.30 (26.25, 36.35) 2.34 (1.85, 2.84)
170 40
69.8 62.1
16.4 13.24
84.8 77.2
16.3 15.4
17.2% 14.8%
15.00 (11.52, 18.48) 0.92 (0.69, 1.14) 15.10 (8.81, 21.39) 1.04 (0.57, 1.51)
201
56.1
15.9
78.2
15.8
17.3%
22.10 (19.00, 25.20) 1.39 (1.17, 1.61)
23
49.5
19.6
74
19.5
12.8%
24.50 (13.20, 35.80) 1.23 (0.60, 1.87)
Author (year) and reference
Number of hips (subgroup)
Brunner et al.33 (2009) Brunner et al.34 (2009) Haviv et al.36 (2010) Javed and O’Donnell37 (2011) Palmer et al.38 (2012) Stahelin et al.13 (2008) Total Weighted mean statistical analysis: Overall size of effect statistical analysis:
Effect Size (95% CI)
537 100% 24.09 (18.42, 29.76) 1.58 (1.16, 2.00) Heterogeneity: Tau2 ¼ 47.52; Chi2 ¼ 47.03, df ¼ 6 (P < 0.00001); I2 ¼ 87% Test for overall effect: Z ¼ 8.32 (P < 0.00001) Heterogeneity: Tau2 ¼ 0.25; Chi2 ¼ 45.14, df ¼ 6 (P < 0.00001); I2 ¼ 87% Test for overall effect: Z ¼ 7.34 (P < 0.00001)
a Weight is illustrated for weighted mean rather than effect size. df: degrees of freedom; IV: inverse variance; NAHS: Non-arthritic Hip Score (0–100); SD: standard deviation; ¥: calculated using method described by Walter and Yao (see ‘Methods’ section).
95% confidence interval and the overall weighted mean change is shown in Figure 2.
Discussion There were no randomised controlled trials which met the inclusion criteria that compared non-operative and operative treatments. Three studies were retrospective,32,36,37 while six were prospective.13,21,33–35,38 One of the papers by Brunner compared computer navigated with conventional arthroscopic surgery33 but no clinical advantage was noted with navigation. The NAHS was the most common outcome measure used in six studies,13,33,34,36–38 the Modified Harris Hip Score (MHHS) was used in four32,35–37 and WOMAC in one.21 All nine studies reported improvements in the clinical outcome scores used, and those that reported complication rates described these as being low. Variable definitions of failure were used, including decreased clinical outcome score, conversion to THR and revision surgery. Where complications were discussed, generally a
