Knee Surg Sports Traumatol Arthrosc DOI 10.1007/s00167-014-2886-8
HIP
Surgical management of labral tears during femoroacetabular impingement surgery: a systematic review O. R. Ayeni • J. Adamich • F. Farrokhyar • N. Simunovic • S. Crouch • M. J. Philippon M. Bhandari
•
Received: 13 November 2013 / Accepted: 28 January 2014 Ó Springer-Verlag Berlin Heidelberg 2014
Abstract Purpose This systematic review explored reported outcomes addressing femoroacetabular impingement (FAI), specifically those comparing labral debridement to labral repair. In addition, the quality of the evidence was evaluated for the purposes of making treatment recommendations. Methods Three databases (MEDLINE, EMBASE, and PubMed) were searched for comparative studies involving labral repair and debridement during FAI surgery. Two reviewers conducted a title, abstract, and full-text review of eligible studies and the references of these studies. Inclusion and exclusion criteria were applied to the searched studies, data were extracted, and a quality assessment was completed for included studies. Results Six eligible studies involving 490 patients were identified. The most commonly reported outcome measure was the modified Harris hip score (MHHS) (50 %). All studies reported that labral repair had greater postoperative improvements in functional scores (modified Harris hip,
non-arthritic hip, hip outcome, and Merle d’Aubigne scores) compared to labral debridement. Five studies reported statistically significant improvements with labral repair. MHHS were pooled to demonstrate a clinically important difference in favor of labral repair by 7.4 points in three studies. The mean individual study quality can be considered fair. However, the overall quality of the body of evidence in this review is rated as low according to GRADE guidelines. Conclusions This review demonstrates a reporting of better clinical outcomes with labral repair compared to labral debridement in all studies with five of six studies reporting statistically significant improvements (of repair over debridement). However, given the lack of high quality evidence and associated limitations in study design, these results should be interpreted with caution. Consequently, definitive treatment recommendations require further investigation with well-conducted clinical trials. This systematic review enables the discussion of best evidence practice for the surgical managing of a labral tear associated with FAI. Level of evidence III.
Electronic supplementary material The online version of this article (doi:10.1007/s00167-014-2886-8) contains supplementary material, which is available to authorized users.
Keywords Femoroacetabular impingement Labrum Systematic review Hip Evidence
O. R. Ayeni (&) J. Adamich M. Bhandari Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, ON, Canada e-mail: [email protected]
Introduction
F. Farrokhyar N. Simunovic S. Crouch M. Bhandari Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada M. J. Philippon Steadman Philippon Research Institute, Vail, CO, USA
The labrum is fibrocartilaginous tissue that is connected to the osseous edge of the acetabulum. The labrum acts to deepen the acetabular socket while extending coverage of the femoral head [9]. The inferior aspect of the labrum joins smoothly with the transverse ligament of the acetabulum, bridging across the acetabular notch,
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thereby extending the circumference of the acetabulum [9]. There is emerging evidence regarding the function of the acetabular labrum and the significance of pathology. Several authors have demonstrated that the labrum aids in stabilizing the hip joint [6, 26]. The seal creates a negative pressure upon distraction and increases the resistance to dislocation. Furthermore, the sealing mechanism of the labrum may contribute to the lubrication of the hip joint, preventing direct cartilage contact [9]. The labral seal allows for loads applied to the hip joint to be carried by fluid pressure within the cartilage, thus protecting the cartilage from high contact stresses [1, 9, 19]. Femoroacetabular impingement (FAI) is a clinical syndrome, involving abnormalities in the structure and orientation of the hip joint, which causes hip pain and contributes to the development of early hip osteoarthrosis [10, 17]. CAM type impingement results from a nonspherical portion of the femoral head-neck junction, and pincer type impingement is the result of focal or global over-coverage by the acetabular rim [10, 17]. Beck et al. [4, 22] report a mixed subtype involving varying degrees both CAM and pincer impingement to be the most prominent subtype in FAI patients. It has been proposed that FAI-related damage to intra-articular structures leads to the development of osteoarthritis of the hip [28]. Thus, surgical intervention is aimed at restoring normal hip mechanics and treating existing damage. Labral debridement and labral repair are surgical treatment options for treating damaged labral tissue when addressing FAI [13]. Labral debridement involves the selective removal of damaged labral tissue [13, 23]. Labral repair involves repair of the labral tissue to the acetabulum rim. The purpose of this systematic review was to document the evidence for the surgical management of the labral pathology associated with FAI and associated treatment effects on outcomes.
Materials and methods Two reviewers searched three databases (MEDLINE, EMBASE, and PubMed) for comparative studies involving labral repair and debridement during FAI surgery. The search strategy combined the following terms: arthroscopy, debridement, hip injuries, joint diseases, hip joint, cartilage injury, and acetabular labral tear. Articles published from 1960 to April 2013 were screened. One reviewer completed the initial title and abstract review. Both reviewers completed a full-text review of the clinical studies independently. Disagreements regarding study and
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data inclusion were resolved by a consensus discussion including the senior author. Assessment of study eligibility The inclusion criteria for this review were as follows: (1) comparative study (i.e., case–control, cohort or randomized controlled trial) comparing labral repair versus debridement, (2) surgical treatment of FAI, (3) study involving human patients, and (4) study published in English. Exclusion criteria were: (1) basic science or non-human studies, (2) review articles, and (3) technique papers. One reviewer completed the initial title review (JA) and then both reviewers screened abstracts for eligible studies (JA & SC). The full-text review was also conducted in duplicate, and all references were hand-searched for additional studies. Data were extracted in duplicate. An intra-class correlation coefficient (ICC) was used to determine agreement between reviewers with a 95 % confidence interval (CI). The guideline suggested by Landis and Koch was applied for measures of agreement. A kappa/ICC of 0–0.2 represents slight agreement, 0.21–0.40 is fair agreement, 0.41–0.60 is moderate agreement, and 0.61–0.80 is substantial agreement. A value above 0.80 is considered almost perfect agreement [14]. Assessment of methodological quality Both reviewers conducted a quality assessment of the included articles. All studies were graded for the level of evidence according to the criteria of Wright et al. [29] published in 2005. Additionally, studies were graded for quality using the methodology index for a non-randomized study (MINORS) developed and validated by Slim et al. [25]. The ninth question of the MINORS scale regarding the comparison to a gold standard was removed, as there is no universally accepted gold standard for FAI surgery, making the final score out of 22. The reliability of MINORS was established by means of good inter-reviewer agreement, high test–retest reliability, and strong internal consistency. The external validity was also established in the ability of the MINORS scale to identify excellent studies [25]. We used the CONSORT (consolidated standards of reporting trials) checklist developed by Moher et al. [20] to assess the quality of any available randomized controlled trials (RCTs). The CONSORT checklist was developed as a means to improve the quality of reports of randomized controlled trials. Following the consort guidelines has been shown to increase the methodological quality of RCTs [21]. The existing body evidence was evaluated using the GRADE criteria to assess the ability to make treatment recommendations from the current review [2].
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Data abstraction Two reviewers collected data independently and reached a consensus on any discrepancies. Abstracted data included the following: authors, date of publication, indication for surgery, clinical indications, outcomes, and complications. In addition, we recorded the location, patient characteristics (e.g., percentage of male patients), mean age, and sample size. Statistical analysis Data abstracted from all included studies were organized into a table. An attempt was made to pool any evidence of common outcomes and interventions as specified a priori. Frequencies and means with standard deviations (SD) for demographics, preoperative, and postoperative measures were retrieved from the articles. SD were estimated from range or were extracted from graphs if not reported in the text, or were imputed using mean values in the case of missing data. For comparing the improvement of modified Harris hip score (MHHS) between the two procedures, the mean change from preoperative scores was calculated for labral repair and labral debridement procedures for approximate 32 months follow-up time. The mean difference in the MHHS change from preoperative scores between labral repair and labral debridement procedures was calculated and reported with 95 % CIs. For this analysis, we used random effects model using inverse variance method to account for between studies heterogeneity, small number of studies, and biases inherent to observational designs. A random effects model meta-analysis assumes that the true underlying effects vary between studies. To assess heterogeneity across studies, we used Cochrane Chisquare Q test based on the pooled mean difference. Heterogeneity was considered statistically significant at p B 0.1 because the heterogeneity test is underpowered when a small number of studies are included. Also, the I2 statistic was used to quantify heterogeneity; a value greater than 50 % considered as substantial heterogeneity. Cochrane Chi-square statistic with p value and I2 value are reported. A p value of 0.05 was considered for statistical significance. Review Manager version 5.1 (www.cochra nelibrary.com) and Microsoft Excel was used for analysis. The estimated clinically significant difference in MHHS was 6.0 with a SD of 8.0 in each group, as reported by Larson et al. [15]. An ICC was used to determine agreement between reviewers with a 95 % CI [3].
Results Our literature search identified 325 individual studies, of which six met the inclusion criteria and were selected for
Fig. 1 Literature search outlining reasons for exclusion of identified articles
this review [8, 13, 15, 16, 22, 24] (Fig. 1). The reviewers had perfect agreement at the full-text stage of the review. Study quality There were five Level III studies (86 %), [8, 15, 16, 22, 24], which included four retrospective cohort studies [8, 15, 16, 24] and one prospective cohort [22]. There was one randomized controlled trial [13] (Table 1). The non-randomized studies had a mean MINORS quality assessment score of 16 of 22 (range 14–18); the randomized control trial met 78 % of the CONSORT checklist items (19.5/25). There were no studies included in this review that were of high methodological quality (defined as a randomized study meeting 80 % of the CONSORT checklist criteria or cohort study meeting 80 % of MINORS checklist criteria). There was excellent agreement between reviewers for the quality assessment (ICC = 0.92, 95 % CI 0.88–0.94). Study characteristics All included studies were completed between 2007 and 2013. There were a total of 490 patients with a mean of 82 patients per study (range 36–112). Of six included studies, 221 patients were treated with labral debridement and 269 patients were treated with labral repairs. The overall weighted mean age was 35.5 years (Standard Deviation, SD 5.5) for labral debridement and 34.7 years (SD 5.8) for labral repair. The mean follow-up was 38 months (SD 6.6)
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Knee Surg Sports Traumatol Arthrosc Table 1 Study characteristics and quality scores References
Location
Study design
Espinosa et al. [8]
Switzerland
Comparative (retrospective chart review)
Krych et al. [13]
USA
Larson et al. [15]
USA
Prospective Randomized Study Comparative (retrospective cohort)
Laude et al. [16]
France
Philippon et al. [22] Schilders et al. [24] a
Sample size
% Male
Mean age
Type of surgery
Surgeon expertise
Length of follow-up (months)
Level of evidence
MINORS score
52
22
30y
Open (surgical dislocation)
N/A
24
3
16 of 22
36
32
38.5y
Arthroscopic
Senior Author
32
1
19.5 of 25a
96
27
29.8y
Arthroscopic
Senior Author
42
3
16 of 22
Comparative (retrospective chart review)
93
36
33.4y
Mini-open (arthroscopicassisted)
Senior Author
58.3
3
14 of 22
USA
Comparative (Prospective cohort)
112
17
40.6y
Arthroscopic
Senior Author
27.6
3
16 of 22
UK
Comparative (retrospective cohort)
101
75
37y
Arthroscopic
Senior Author
29.3
3
18 of 22
CONSORT quality score for randomized trials
Table 2 Clinical and radiographic outcomes reported in included studies
Clinical outcome measures reported
Clinical outcomes
No. of studies (%)
References
Modified Harris hip score
57
[15, 22, 24]
HOS activities of daily living (ADL)
29
[13, 22]a
Reported clinical outcomes included standardized outcome scores, physical examinations, analog scales, patient status, as well as return to sports (Table 2). The most commonly reported standardized outcome measure was the MHHS (n = 3 studies [15, 22, 24], 50 %). The majority of studies reported a combination of clinical and radiographic outcomes.
Pain on visual analog scale
29
[15]
Christensen non-arthritic hip score
29
[16, 22]a
Alpha angle (X-ray)
43
[15, 22]
Merle d’Aubigne score
14
[7]
Merle d’Aubigne pain score
14
[7]
Tonnis grade
29
[7, 15]
SF-12
29
[15]
HOS for sports
29
[13, 22]a
Complications stated
61
[7, 15, 16, 22]
Hip self-assessment Self-administered Questionnaire
14 14
[13] [22]a
Patient satisfaction
14
[22]a
Arthroscopic surgery
61
[13, 15, 22, 24]
Open procedure
29
[7, 16]
a
Outcome measure reported but do not separate repair from debridement
for labral debridement and 35.0 months (SD 5.3) for labral repair. Indications for surgery were stated in a total of three articles (50 %) [8, 15, 22]. Of the six included studies, five utilized the arthroscopic technique [13, 15, 22, 24] and two used an open approach [8, 16].
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Comparative outcomes Our systematic review identified a total of 221 patients managed with labral debridement and 269 patients who were managed utilizing labral repair utilizing either an arthroscopic or open approach. Table 2 depicts all reported outcomes by the authors of the included studies. Arthroscopic management of FAI resulted in postoperative improvements (mean MHHS) that were greater in the studies involving labral repair compared with labral debridement, although both had improvement [15, 22, 24]. There was a significant difference reported in favor of the repair group in 67 % (2/3) of the observational studies and one randomized controlled trial (p \ 0.5) [13] (Online Resource 1). Open management of FAI produced mixed results in comparing labral repair to debridement. Espinosa et al. [8] reported a statistically significant advantage (p = 0.01) of labral repair over debridement (mean difference of 5 vs. 3) while no significant difference between the two techniques was found by Laude et al. [16] (mean difference of 31.2 vs. 27.2) (Online Resource 1).
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Fig. 2 Forest plot of the modified Harris hip scores
There was a significant difference in the postoperative VAS pain scores between the labral debridement and repair groups (p = 0.04). On the contrary, the mean difference in improvement between repair group and the debridement group was 0.2 (5 vs. 4.8), demonstrating the difference may in fact be negligible [15]. Open management of FAI reported a significant difference in the postoperative Merle d’Aubigne pain scores (out of 6) between debridement and repair groups (p = 0.001). The mean difference in the labral repair group compared to the debridement was 4.2 versus 3.5 at last follow-up [8]. No significant differences in alpha angles were noted between the labral debridement and repair techniques. Pooled clinical outcomes Three studies assessed and compared MHHS between the two procedures [15, 22, 24]. The preoperative and postoperative MHHS means and mean change from preoperative score with SD for these three studies are shown in a Forrest plot (Fig. 2). The pooled evidence revealed that labral repair is associated with statistically significant improvements in MHHS when compared to labral debridement. The difference in means between groups was 7.41 in favor of labral repair meeting the criteria specified a priori for a clinically important difference. Similar results were noted in studies reporting other outcome measures (Table 2). Complications A total of ten complications were noted in the 558 patients (1.8 %). Arthroscopic management resulted in six complications (1.5 %), all of these patients having undergone labral debridement (3.5 %). The remaining four complications occurred in patients that underwent open management of FAI (2.8 %), but the labral management technique used was unstated. Chi square revealed an insignificant difference (a [ 0.3) in complications between arthroscopic and open studies. Of the 172 patients that underwent arthroscopic debridement, there were a total of eight failures and
corresponding reoperations (4.7 %). Of the 220 patients that underwent arthroscopic labral repair, there were no failures and four reoperations (1.8 %). Arthroscopic management with labral repair had no complications (0/220), while three (3/172) heterotopic bone formations occurred with labral debridement. There were a total of 73 patients that underwent open debridement, and 72 that underwent open labral repair. A total of 13 reoperations (9.0 %) and four complications (2.8 %) were reported in both groups combined. These complications included: one femoral head fracture, one heterotopic bone formation, and two deep infections. GRADE recommendation for repair versus debridement According to the GRADE guidelines, the overall quality of the body of evidence was found to be low [2]. The body of evidence is composed mainly of lower quality observational studies with methodological limitations. Individual GRADE evaluations are shown in Table 3.
Discussion There has been a dramatic increase in the number of hip arthroscopies being performed in the USA, and this increase is likely to occur elsewhere [5]. The increased interest in hip disorders has resulted in technological developments that allow for surgical techniques such as labral repair [7]. This review is the most recent attempt to evaluate the current state of the literature addressing management of labral tears during FAI surgery. Despite the biological rationale for repairing the labrum (maintaining stability, repair of the sealing mechanism, decreasing cartilage contact), the most important finding of this review is that higher level clinical evidence is needed to substantiate the clinical improvements of labral repair over debridement [30]. In this review, labral repairs resulted in superior outcomes when compared to labral debridement (6 of 6 included studies). Five of these studies report the
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Knee Surg Sports Traumatol Arthrosc Table 3 GRADE evaluation for each included study in the review Study
Observational studies risk of bias
Final GRADE
Eligibility criteria
Flawed measurement
Incomplete followup
Control confounding
Espinosa et al. [8]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
100 % Follow-up
No statistically significant differences between groups
Larson et al. [15]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
94 % Follow-up
No statistically significant differences between groups
Laude et al. [16]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
94 % Follow-up
Adjustment in statistical analysis
Philippon et al. [22]
Adequate inclusion criteria
80 % Follow-up
Unknown
Schilders et al. [24]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques Consistent reporting of standardized measures and surveillance techniques
100 % Follow-up
Adjustment in statistical analysis
Randomized controlled trial risk of bias
Krych et al. [13]
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Final GRADE
Blinding
Randomization and allocation concealment
Loss to follow-up
Surgeon and patient were not blinded
Sealed opaque envelopes
100 % Follow-up
improvements as statistically significant [8, 13, 15, 22, 24]. There was a variety of postoperative clinical and radiographic parameters reported. The available literature was also noted to be predominantly observational in design (five cohort studies) with a single moderate quality RCT. Although patients and surgeons confronted with a diagnosis of a ‘‘labral tear’’ may inherently think that a repair is most appropriate, the current literature suggests better outcomes with a repair but does not provide definitive information. This systematic review is strengthened by the methodological approach taken with a broad literature search of multiple databases and duplicate data abstraction and quality assessments. Furthermore, the Mean MHHS was pooled to create a Forrest plot to delineate outcomes with a commonly used outcome measure. Lastly, to increase translational value of the findings of this systematic review, the quality of the body of literature was assessed using the GRADE criteria to facilitate treatment recommendations. However, there are several important limitations. First, there was a lack of high quality evidence to inform recommendations. Second, the included studies used a variety of clinical and radiographic outcome measures, which prevented further pooling. Finally, the included studies generally had a follow-up period of less than 3 years, leaving the long-term success of labral tissue management unknown.
Low
Selective outcome reporting and other Validated outcome measures;
Low
Only female population
Certain challenges exist in current research addressing labral repair and debridement. First, the impact of surgeon learning curve is rarely assessed, and this is particularly important in a surgery of this complexity. As such it is possible that labral repairs were pursued selectively by experienced experts, leading to biased reporting of outcomes [12, 27]. Furthermore, surgeons who performed labral debridement initially may be more likely to investigate failures of treatment or complications than those who performed repairs as the index procedure. Factors that may affect the ability to treat labral tissue such as: tear pattern, tissue quality, patient compliance with rehabilitation, and general health of patients should be evaluated as potential prognostic indices in future studies. Such an approach is commonly applied to the meniscus tears when determining which meniscus tears are repaired or debrided [18]. Updated reports on the current patients in this review followed for longer periods of time can also help with analyzing the patients with treatment failures that require subsequent surgeries. From this, prognostic indices can be developed. In addition to studies that evaluate outcomes on a long-term basis, the development of a validated measurement tool that evaluates outcomes following surgical management of the labrum will be important. A previous systematic review has demonstrated that reported outcomes following FAI surgery have been inconsistently reported
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[11]. As such, the ability to use validated clinical and radiographic parameters that address labral pathology consistently will be very helpful. With the availability of such tools, the minimally important clinical difference can be determined a priori when conducting comparative trials. Nevertheless, this systematic review enables the discussion of best evidence and practice for the surgical managing of a labral tear associated with FAI.
Conclusion Labral tears associated with FAI can be treated using either labral debridement or labral repair. This review demonstrates improved short-term clinical outcomes, a decreased failure rate, and fewer complications with labral repair compared with debridement. However, given the lack of high quality evidence, these results should be interpreted with caution and further high-level comparative trials conducted. Acknowledgments Research Chair.
M. Bhandari is funded in part by a Canada
Conflict of interest The authors report that they have no conflict of interest in the authorship and publication of this article.
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Surgical management of labral tears during femoroacetabular impingement surgery: a systematic review O. R. Ayeni • J. Adamich • F. Farrokhyar • N. Simunovic • S. Crouch • M. J. Philippon M. Bhandari
•
Received: 13 November 2013 / Accepted: 28 January 2014 Ó Springer-Verlag Berlin Heidelberg 2014
Abstract Purpose This systematic review explored reported outcomes addressing femoroacetabular impingement (FAI), specifically those comparing labral debridement to labral repair. In addition, the quality of the evidence was evaluated for the purposes of making treatment recommendations. Methods Three databases (MEDLINE, EMBASE, and PubMed) were searched for comparative studies involving labral repair and debridement during FAI surgery. Two reviewers conducted a title, abstract, and full-text review of eligible studies and the references of these studies. Inclusion and exclusion criteria were applied to the searched studies, data were extracted, and a quality assessment was completed for included studies. Results Six eligible studies involving 490 patients were identified. The most commonly reported outcome measure was the modified Harris hip score (MHHS) (50 %). All studies reported that labral repair had greater postoperative improvements in functional scores (modified Harris hip,
non-arthritic hip, hip outcome, and Merle d’Aubigne scores) compared to labral debridement. Five studies reported statistically significant improvements with labral repair. MHHS were pooled to demonstrate a clinically important difference in favor of labral repair by 7.4 points in three studies. The mean individual study quality can be considered fair. However, the overall quality of the body of evidence in this review is rated as low according to GRADE guidelines. Conclusions This review demonstrates a reporting of better clinical outcomes with labral repair compared to labral debridement in all studies with five of six studies reporting statistically significant improvements (of repair over debridement). However, given the lack of high quality evidence and associated limitations in study design, these results should be interpreted with caution. Consequently, definitive treatment recommendations require further investigation with well-conducted clinical trials. This systematic review enables the discussion of best evidence practice for the surgical managing of a labral tear associated with FAI. Level of evidence III.
Electronic supplementary material The online version of this article (doi:10.1007/s00167-014-2886-8) contains supplementary material, which is available to authorized users.
Keywords Femoroacetabular impingement Labrum Systematic review Hip Evidence
O. R. Ayeni (&) J. Adamich M. Bhandari Division of Orthopaedic Surgery, Department of Surgery, McMaster University, Hamilton, ON, Canada e-mail: [email protected]
Introduction
F. Farrokhyar N. Simunovic S. Crouch M. Bhandari Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada M. J. Philippon Steadman Philippon Research Institute, Vail, CO, USA
The labrum is fibrocartilaginous tissue that is connected to the osseous edge of the acetabulum. The labrum acts to deepen the acetabular socket while extending coverage of the femoral head [9]. The inferior aspect of the labrum joins smoothly with the transverse ligament of the acetabulum, bridging across the acetabular notch,
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thereby extending the circumference of the acetabulum [9]. There is emerging evidence regarding the function of the acetabular labrum and the significance of pathology. Several authors have demonstrated that the labrum aids in stabilizing the hip joint [6, 26]. The seal creates a negative pressure upon distraction and increases the resistance to dislocation. Furthermore, the sealing mechanism of the labrum may contribute to the lubrication of the hip joint, preventing direct cartilage contact [9]. The labral seal allows for loads applied to the hip joint to be carried by fluid pressure within the cartilage, thus protecting the cartilage from high contact stresses [1, 9, 19]. Femoroacetabular impingement (FAI) is a clinical syndrome, involving abnormalities in the structure and orientation of the hip joint, which causes hip pain and contributes to the development of early hip osteoarthrosis [10, 17]. CAM type impingement results from a nonspherical portion of the femoral head-neck junction, and pincer type impingement is the result of focal or global over-coverage by the acetabular rim [10, 17]. Beck et al. [4, 22] report a mixed subtype involving varying degrees both CAM and pincer impingement to be the most prominent subtype in FAI patients. It has been proposed that FAI-related damage to intra-articular structures leads to the development of osteoarthritis of the hip [28]. Thus, surgical intervention is aimed at restoring normal hip mechanics and treating existing damage. Labral debridement and labral repair are surgical treatment options for treating damaged labral tissue when addressing FAI [13]. Labral debridement involves the selective removal of damaged labral tissue [13, 23]. Labral repair involves repair of the labral tissue to the acetabulum rim. The purpose of this systematic review was to document the evidence for the surgical management of the labral pathology associated with FAI and associated treatment effects on outcomes.
Materials and methods Two reviewers searched three databases (MEDLINE, EMBASE, and PubMed) for comparative studies involving labral repair and debridement during FAI surgery. The search strategy combined the following terms: arthroscopy, debridement, hip injuries, joint diseases, hip joint, cartilage injury, and acetabular labral tear. Articles published from 1960 to April 2013 were screened. One reviewer completed the initial title and abstract review. Both reviewers completed a full-text review of the clinical studies independently. Disagreements regarding study and
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data inclusion were resolved by a consensus discussion including the senior author. Assessment of study eligibility The inclusion criteria for this review were as follows: (1) comparative study (i.e., case–control, cohort or randomized controlled trial) comparing labral repair versus debridement, (2) surgical treatment of FAI, (3) study involving human patients, and (4) study published in English. Exclusion criteria were: (1) basic science or non-human studies, (2) review articles, and (3) technique papers. One reviewer completed the initial title review (JA) and then both reviewers screened abstracts for eligible studies (JA & SC). The full-text review was also conducted in duplicate, and all references were hand-searched for additional studies. Data were extracted in duplicate. An intra-class correlation coefficient (ICC) was used to determine agreement between reviewers with a 95 % confidence interval (CI). The guideline suggested by Landis and Koch was applied for measures of agreement. A kappa/ICC of 0–0.2 represents slight agreement, 0.21–0.40 is fair agreement, 0.41–0.60 is moderate agreement, and 0.61–0.80 is substantial agreement. A value above 0.80 is considered almost perfect agreement [14]. Assessment of methodological quality Both reviewers conducted a quality assessment of the included articles. All studies were graded for the level of evidence according to the criteria of Wright et al. [29] published in 2005. Additionally, studies were graded for quality using the methodology index for a non-randomized study (MINORS) developed and validated by Slim et al. [25]. The ninth question of the MINORS scale regarding the comparison to a gold standard was removed, as there is no universally accepted gold standard for FAI surgery, making the final score out of 22. The reliability of MINORS was established by means of good inter-reviewer agreement, high test–retest reliability, and strong internal consistency. The external validity was also established in the ability of the MINORS scale to identify excellent studies [25]. We used the CONSORT (consolidated standards of reporting trials) checklist developed by Moher et al. [20] to assess the quality of any available randomized controlled trials (RCTs). The CONSORT checklist was developed as a means to improve the quality of reports of randomized controlled trials. Following the consort guidelines has been shown to increase the methodological quality of RCTs [21]. The existing body evidence was evaluated using the GRADE criteria to assess the ability to make treatment recommendations from the current review [2].
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Data abstraction Two reviewers collected data independently and reached a consensus on any discrepancies. Abstracted data included the following: authors, date of publication, indication for surgery, clinical indications, outcomes, and complications. In addition, we recorded the location, patient characteristics (e.g., percentage of male patients), mean age, and sample size. Statistical analysis Data abstracted from all included studies were organized into a table. An attempt was made to pool any evidence of common outcomes and interventions as specified a priori. Frequencies and means with standard deviations (SD) for demographics, preoperative, and postoperative measures were retrieved from the articles. SD were estimated from range or were extracted from graphs if not reported in the text, or were imputed using mean values in the case of missing data. For comparing the improvement of modified Harris hip score (MHHS) between the two procedures, the mean change from preoperative scores was calculated for labral repair and labral debridement procedures for approximate 32 months follow-up time. The mean difference in the MHHS change from preoperative scores between labral repair and labral debridement procedures was calculated and reported with 95 % CIs. For this analysis, we used random effects model using inverse variance method to account for between studies heterogeneity, small number of studies, and biases inherent to observational designs. A random effects model meta-analysis assumes that the true underlying effects vary between studies. To assess heterogeneity across studies, we used Cochrane Chisquare Q test based on the pooled mean difference. Heterogeneity was considered statistically significant at p B 0.1 because the heterogeneity test is underpowered when a small number of studies are included. Also, the I2 statistic was used to quantify heterogeneity; a value greater than 50 % considered as substantial heterogeneity. Cochrane Chi-square statistic with p value and I2 value are reported. A p value of 0.05 was considered for statistical significance. Review Manager version 5.1 (www.cochra nelibrary.com) and Microsoft Excel was used for analysis. The estimated clinically significant difference in MHHS was 6.0 with a SD of 8.0 in each group, as reported by Larson et al. [15]. An ICC was used to determine agreement between reviewers with a 95 % CI [3].
Results Our literature search identified 325 individual studies, of which six met the inclusion criteria and were selected for
Fig. 1 Literature search outlining reasons for exclusion of identified articles
this review [8, 13, 15, 16, 22, 24] (Fig. 1). The reviewers had perfect agreement at the full-text stage of the review. Study quality There were five Level III studies (86 %), [8, 15, 16, 22, 24], which included four retrospective cohort studies [8, 15, 16, 24] and one prospective cohort [22]. There was one randomized controlled trial [13] (Table 1). The non-randomized studies had a mean MINORS quality assessment score of 16 of 22 (range 14–18); the randomized control trial met 78 % of the CONSORT checklist items (19.5/25). There were no studies included in this review that were of high methodological quality (defined as a randomized study meeting 80 % of the CONSORT checklist criteria or cohort study meeting 80 % of MINORS checklist criteria). There was excellent agreement between reviewers for the quality assessment (ICC = 0.92, 95 % CI 0.88–0.94). Study characteristics All included studies were completed between 2007 and 2013. There were a total of 490 patients with a mean of 82 patients per study (range 36–112). Of six included studies, 221 patients were treated with labral debridement and 269 patients were treated with labral repairs. The overall weighted mean age was 35.5 years (Standard Deviation, SD 5.5) for labral debridement and 34.7 years (SD 5.8) for labral repair. The mean follow-up was 38 months (SD 6.6)
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Knee Surg Sports Traumatol Arthrosc Table 1 Study characteristics and quality scores References
Location
Study design
Espinosa et al. [8]
Switzerland
Comparative (retrospective chart review)
Krych et al. [13]
USA
Larson et al. [15]
USA
Prospective Randomized Study Comparative (retrospective cohort)
Laude et al. [16]
France
Philippon et al. [22] Schilders et al. [24] a
Sample size
% Male
Mean age
Type of surgery
Surgeon expertise
Length of follow-up (months)
Level of evidence
MINORS score
52
22
30y
Open (surgical dislocation)
N/A
24
3
16 of 22
36
32
38.5y
Arthroscopic
Senior Author
32
1
19.5 of 25a
96
27
29.8y
Arthroscopic
Senior Author
42
3
16 of 22
Comparative (retrospective chart review)
93
36
33.4y
Mini-open (arthroscopicassisted)
Senior Author
58.3
3
14 of 22
USA
Comparative (Prospective cohort)
112
17
40.6y
Arthroscopic
Senior Author
27.6
3
16 of 22
UK
Comparative (retrospective cohort)
101
75
37y
Arthroscopic
Senior Author
29.3
3
18 of 22
CONSORT quality score for randomized trials
Table 2 Clinical and radiographic outcomes reported in included studies
Clinical outcome measures reported
Clinical outcomes
No. of studies (%)
References
Modified Harris hip score
57
[15, 22, 24]
HOS activities of daily living (ADL)
29
[13, 22]a
Reported clinical outcomes included standardized outcome scores, physical examinations, analog scales, patient status, as well as return to sports (Table 2). The most commonly reported standardized outcome measure was the MHHS (n = 3 studies [15, 22, 24], 50 %). The majority of studies reported a combination of clinical and radiographic outcomes.
Pain on visual analog scale
29
[15]
Christensen non-arthritic hip score
29
[16, 22]a
Alpha angle (X-ray)
43
[15, 22]
Merle d’Aubigne score
14
[7]
Merle d’Aubigne pain score
14
[7]
Tonnis grade
29
[7, 15]
SF-12
29
[15]
HOS for sports
29
[13, 22]a
Complications stated
61
[7, 15, 16, 22]
Hip self-assessment Self-administered Questionnaire
14 14
[13] [22]a
Patient satisfaction
14
[22]a
Arthroscopic surgery
61
[13, 15, 22, 24]
Open procedure
29
[7, 16]
a
Outcome measure reported but do not separate repair from debridement
for labral debridement and 35.0 months (SD 5.3) for labral repair. Indications for surgery were stated in a total of three articles (50 %) [8, 15, 22]. Of the six included studies, five utilized the arthroscopic technique [13, 15, 22, 24] and two used an open approach [8, 16].
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Comparative outcomes Our systematic review identified a total of 221 patients managed with labral debridement and 269 patients who were managed utilizing labral repair utilizing either an arthroscopic or open approach. Table 2 depicts all reported outcomes by the authors of the included studies. Arthroscopic management of FAI resulted in postoperative improvements (mean MHHS) that were greater in the studies involving labral repair compared with labral debridement, although both had improvement [15, 22, 24]. There was a significant difference reported in favor of the repair group in 67 % (2/3) of the observational studies and one randomized controlled trial (p \ 0.5) [13] (Online Resource 1). Open management of FAI produced mixed results in comparing labral repair to debridement. Espinosa et al. [8] reported a statistically significant advantage (p = 0.01) of labral repair over debridement (mean difference of 5 vs. 3) while no significant difference between the two techniques was found by Laude et al. [16] (mean difference of 31.2 vs. 27.2) (Online Resource 1).
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Fig. 2 Forest plot of the modified Harris hip scores
There was a significant difference in the postoperative VAS pain scores between the labral debridement and repair groups (p = 0.04). On the contrary, the mean difference in improvement between repair group and the debridement group was 0.2 (5 vs. 4.8), demonstrating the difference may in fact be negligible [15]. Open management of FAI reported a significant difference in the postoperative Merle d’Aubigne pain scores (out of 6) between debridement and repair groups (p = 0.001). The mean difference in the labral repair group compared to the debridement was 4.2 versus 3.5 at last follow-up [8]. No significant differences in alpha angles were noted between the labral debridement and repair techniques. Pooled clinical outcomes Three studies assessed and compared MHHS between the two procedures [15, 22, 24]. The preoperative and postoperative MHHS means and mean change from preoperative score with SD for these three studies are shown in a Forrest plot (Fig. 2). The pooled evidence revealed that labral repair is associated with statistically significant improvements in MHHS when compared to labral debridement. The difference in means between groups was 7.41 in favor of labral repair meeting the criteria specified a priori for a clinically important difference. Similar results were noted in studies reporting other outcome measures (Table 2). Complications A total of ten complications were noted in the 558 patients (1.8 %). Arthroscopic management resulted in six complications (1.5 %), all of these patients having undergone labral debridement (3.5 %). The remaining four complications occurred in patients that underwent open management of FAI (2.8 %), but the labral management technique used was unstated. Chi square revealed an insignificant difference (a [ 0.3) in complications between arthroscopic and open studies. Of the 172 patients that underwent arthroscopic debridement, there were a total of eight failures and
corresponding reoperations (4.7 %). Of the 220 patients that underwent arthroscopic labral repair, there were no failures and four reoperations (1.8 %). Arthroscopic management with labral repair had no complications (0/220), while three (3/172) heterotopic bone formations occurred with labral debridement. There were a total of 73 patients that underwent open debridement, and 72 that underwent open labral repair. A total of 13 reoperations (9.0 %) and four complications (2.8 %) were reported in both groups combined. These complications included: one femoral head fracture, one heterotopic bone formation, and two deep infections. GRADE recommendation for repair versus debridement According to the GRADE guidelines, the overall quality of the body of evidence was found to be low [2]. The body of evidence is composed mainly of lower quality observational studies with methodological limitations. Individual GRADE evaluations are shown in Table 3.
Discussion There has been a dramatic increase in the number of hip arthroscopies being performed in the USA, and this increase is likely to occur elsewhere [5]. The increased interest in hip disorders has resulted in technological developments that allow for surgical techniques such as labral repair [7]. This review is the most recent attempt to evaluate the current state of the literature addressing management of labral tears during FAI surgery. Despite the biological rationale for repairing the labrum (maintaining stability, repair of the sealing mechanism, decreasing cartilage contact), the most important finding of this review is that higher level clinical evidence is needed to substantiate the clinical improvements of labral repair over debridement [30]. In this review, labral repairs resulted in superior outcomes when compared to labral debridement (6 of 6 included studies). Five of these studies report the
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Knee Surg Sports Traumatol Arthrosc Table 3 GRADE evaluation for each included study in the review Study
Observational studies risk of bias
Final GRADE
Eligibility criteria
Flawed measurement
Incomplete followup
Control confounding
Espinosa et al. [8]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
100 % Follow-up
No statistically significant differences between groups
Larson et al. [15]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
94 % Follow-up
No statistically significant differences between groups
Laude et al. [16]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques
94 % Follow-up
Adjustment in statistical analysis
Philippon et al. [22]
Adequate inclusion criteria
80 % Follow-up
Unknown
Schilders et al. [24]
Adequate inclusion criteria
Consistent reporting of standardized measures and surveillance techniques Consistent reporting of standardized measures and surveillance techniques
100 % Follow-up
Adjustment in statistical analysis
Randomized controlled trial risk of bias
Krych et al. [13]
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Final GRADE
Blinding
Randomization and allocation concealment
Loss to follow-up
Surgeon and patient were not blinded
Sealed opaque envelopes
100 % Follow-up
improvements as statistically significant [8, 13, 15, 22, 24]. There was a variety of postoperative clinical and radiographic parameters reported. The available literature was also noted to be predominantly observational in design (five cohort studies) with a single moderate quality RCT. Although patients and surgeons confronted with a diagnosis of a ‘‘labral tear’’ may inherently think that a repair is most appropriate, the current literature suggests better outcomes with a repair but does not provide definitive information. This systematic review is strengthened by the methodological approach taken with a broad literature search of multiple databases and duplicate data abstraction and quality assessments. Furthermore, the Mean MHHS was pooled to create a Forrest plot to delineate outcomes with a commonly used outcome measure. Lastly, to increase translational value of the findings of this systematic review, the quality of the body of literature was assessed using the GRADE criteria to facilitate treatment recommendations. However, there are several important limitations. First, there was a lack of high quality evidence to inform recommendations. Second, the included studies used a variety of clinical and radiographic outcome measures, which prevented further pooling. Finally, the included studies generally had a follow-up period of less than 3 years, leaving the long-term success of labral tissue management unknown.
Low
Selective outcome reporting and other Validated outcome measures;
Low
Only female population
Certain challenges exist in current research addressing labral repair and debridement. First, the impact of surgeon learning curve is rarely assessed, and this is particularly important in a surgery of this complexity. As such it is possible that labral repairs were pursued selectively by experienced experts, leading to biased reporting of outcomes [12, 27]. Furthermore, surgeons who performed labral debridement initially may be more likely to investigate failures of treatment or complications than those who performed repairs as the index procedure. Factors that may affect the ability to treat labral tissue such as: tear pattern, tissue quality, patient compliance with rehabilitation, and general health of patients should be evaluated as potential prognostic indices in future studies. Such an approach is commonly applied to the meniscus tears when determining which meniscus tears are repaired or debrided [18]. Updated reports on the current patients in this review followed for longer periods of time can also help with analyzing the patients with treatment failures that require subsequent surgeries. From this, prognostic indices can be developed. In addition to studies that evaluate outcomes on a long-term basis, the development of a validated measurement tool that evaluates outcomes following surgical management of the labrum will be important. A previous systematic review has demonstrated that reported outcomes following FAI surgery have been inconsistently reported
Knee Surg Sports Traumatol Arthrosc
[11]. As such, the ability to use validated clinical and radiographic parameters that address labral pathology consistently will be very helpful. With the availability of such tools, the minimally important clinical difference can be determined a priori when conducting comparative trials. Nevertheless, this systematic review enables the discussion of best evidence and practice for the surgical managing of a labral tear associated with FAI.
Conclusion Labral tears associated with FAI can be treated using either labral debridement or labral repair. This review demonstrates improved short-term clinical outcomes, a decreased failure rate, and fewer complications with labral repair compared with debridement. However, given the lack of high quality evidence, these results should be interpreted with caution and further high-level comparative trials conducted. Acknowledgments Research Chair.
M. Bhandari is funded in part by a Canada
Conflict of interest The authors report that they have no conflict of interest in the authorship and publication of this article.
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