Surgical Treatment for FAI: Arthroscopic and Open Techniques for Osteoplasty

High incidence of femoroacetabular impingement deformity in bi-column acetabular fractures

INTRODUCTION

Dynamic interaction of cam and pincer deformities can result in pathological contact forces in femoroacetabular impingement (FAI) syndrome. Similar deformities were noted during acetabular fracture reconstruction. We hypothesise that the prevalence of FAI deformity is higher in patients sustaining acetabular fractures than in a control group.

METHODS

This retrospective radiographic study compared the parameters that define FAI deformity in 100 patients consecutively admitted to a trauma unit with an acetabular fracture and a control group of 100 patients with lateral compression pelvic fracture without acetabular injury. Both underwent identical clinical imaging. Centre-edge angles (CEA) and alpha angles were used to define patients with pincer, cam, or mixed FAI deformity.

RESULTS

There were significantly more patients with FAI deformity in the acetabular fracture group than in the control group (71% vs. 18%, p < 0.0001). There were considerably more fractures involving both anterior and posterior acetabular columns in patients with 'pincer' sockets (p = 0.02, OR = 2.95, 95% CI, 1.12-7.78).

CONCLUSIONS

There is a high prevalence of cam and pincer deformities in patients with acetabular fractures, particularly bi-column fractures.

Outcomes associated with hip preservation using osteochondral allograft transplants and acetabular labrum reconstruction

BACKGROUND

Osteochondral allograft (OCA) transplantation with or without labral reconstruction is considered a hip preservation surgical treatment option for young, active patients. This study aims to report early outcomes for use of OCA and labrum allograft transplants for patients treated for symptomatic femoral head chondral damage and/or acetabular labrum deficiency after implementation of a comprehensive joint restoration approach.

METHODS

33 patients from a lifelong registry were included for analysis. Outcomes were compared for statistically significant (p < 0.05) differences based on graft preservation methodology (standard preservation [SP] vs. Missouri Osteochondral Preservation System [MOPS]), and based on surfaces treated (femoral head only, labrum only, or femoral head and labrum).

RESULTS

Mean follow-up duration was 44.8 (range 12-95) months. Success was documented in 28 (84.8%) patients. For the SP cohort, successful outcomes were documented in 5 cases (50%), while all 23 MOPS cases (100%) were deemed successful at least 1 year after surgery. Hip preservation surgeries performed using MOPS grafts were associated with significantly (p = 0.001; OR = 47x) higher success rates, including significant and clinically meaningful improvements in PROMs at 1 and 2 years after surgery. Revision was performed in 2 patients in the SP cohort and failure requiring total hip arthroplasty was documented in 3 SP patients. Mean time to revision or failure was 23.6 (range 4-43) months. The surfaces treated were significantly associated with failure when comparing patients undergoing a femoral head OCA with or without labral reconstruction to those undergoing labral reconstruction only (p = 0.03; OR = 8.3x).

CONCLUSIONS

Patients with symptomatic femoral head cartilage loss and/or irreparable acetabular labrum deficiency undergoing femoral head OCA transplantation and/or labral reconstruction with meniscus allografts using MOPS-preserved tissues experienced statistically significant and clinically meaningful improvements in pain and function through at least 2 years after surgery.

Osteochondroplasty with or without labral repair is more cost-effective than arthroscopic lavage with or without labral repair for treatment of young adults with femoroacetabular impingement: A cost-utility analysis based on data from a randomized controlled trial

OBJECTIVES

The objective of this study was to conduct a cost-utility analysis of osteochondroplasty with or without labral repair compared to arthroscopic lavage with or without labral repair for femoroacetabular impingement (FAI) from a Canadian public payer perspective.

METHODS

A Markov model was constructed to compare the lifetime quality-adjusted life years (QALYs) and costs of the two treatment strategies. The target population was surgical FAI patients aged 36 years. The primary data source was patient-level data from the Femoroacetabular Impingement Randomised Controlled Trial, which evaluated the efficacy of the surgical correction of FAI via arthroscopic osteochondroplasty with or without labral repair compared to arthroscopic lavage with or without labral repair in Canada. Long-term data were extrapolated using a generalized gamma model. The primary outcome was the incremental cost-effectiveness ratio, calculated by dividing the difference in costs by the difference in QALYs between osteochondroplasty and lavage, with or without labral repair. Probabilistic sensitivity analyses and one-way sensitivity analyses were used to characterize uncertainty of model parameters and assumptions.

RESULTS

Over a lifetime horizon, osteochondroplasty, with or without labral repair, had a greater expected benefit (0.63 QALYs gained per patient) and lower costs ($955.89 saved per patient), as compared with lavage with or without labral repair. Probabilistic sensitivity analyses demonstrated that the probability of osteochondroplasty, with or without labral repair, being cost-effective was 90.5% at a commonly used willingness-to-pay threshold of $50,000/QALY in Canada. Across all one-way sensitivity analyses, osteochondroplasty with or without labral repair remained a cost-effective option.

CONCLUSION

Over a lifetime time horizon, osteochondroplasty, with or without labral repair, is a cost-effective treatment strategy for young adults with FAI. Future research involving real-word data is needed to further validate these findings.

LEVEL OF EVIDENCE

III.

Chondral regeneration in femoroacetabular lesions is favoured using peripheral blood stem cells with hyaluronan-based scaffold and micro-drilling: A prospective cohort study

Purpose

To determine whether intra-articular injections of peripheral blood stem cells (PBSC) with hyaluronan (HA)-based scaffold improve articular cartilage regeneration in chondral injuries caused by mixed-femoroacetabular impingement syndrome (FAIS) over a period longer than 24 months post-hip arthroscopy.

Methods

In this prospective cohort study, patients with mixed-FAIS and chondral injury ≥ IIIB according to the International Cartilage Regeneration and Joint Preservation Society grade or III/IV of Konan/Haddad classification underwent intra-articular injection of PBSC with an HA-based scaffold and micro-drillings during hip arthroscopy. The degree of chondral repair was measured at baseline and 5 years using the International Cartilage Repair Society morphologic score system (MSS) as the primary outcome. Pain was measured at baseline and 5 years using the Visual Analogue Scale for Pain (VAS Pain), and hip functionality was measured at baseline (presurgery), 6 months, 1 year, and 5 years using the Hip Outcome Score (HOS). The largest diameter of injury, median follow-up, side effects, complications, and improvements were described. T-test, ANOVA with multiple comparisons, and statistical power were estimated.

Results

From initially 34 cases, 25 patients were enrolled. The median follow-up was 5.1 ± 0.3 years. One patient (4%) reported a few side effects with filgrastim administration. No infection, tumours, or synovitis was reported. The largest diameters in zones two, three, and four were 12.4 ± 3.1 mm (n = 8), 13.5 ± 2.8 mm (n = 14), and 11.4 ± 1.9 mm (n = 3), respectively. Ninety-two percent (23/25) of patients improved their outcomes. The MSS and HOS increased from 3.8 ± 1.1 to 9.6 ± 1.5 pts (p < 0.001) and from 65.5 ± 13.0 to 93.9 ± 2.4 pts (p < 0.001), respectively. The VAS-Pain decreased from 5.3 ± 0.7 to 1.3 ± 0.6 mm (p < 0.001). The obtained a posteriori power-size was 0.99.

Conclusion

The intervention suggests a favourable impact on articular cartilage regeneration and clinical outcomes for hip chondral lesions in mixed-FAIS injuries after a median follow-up of 5.1 ± 0.3 years.

Level of Evidence

Level IV.

The Effect of Pelvic Incidence on Outcomes After Hip Arthroscopy for Femoroacetabular Impingement and Acetabular Labral Tears

BACKGROUND

In the setting of femoroacetabular impingement (FAI), decompression osteoplasties reconcile deleterious loading patterns caused by cam and pincer lesions. However, native variations of spinopelvic sagittal alignment may continue to perpetuate detrimental effects on the labrum, chondrolabral junction, and articular cartilage after hip arthroscopy.

PURPOSE

To evaluate the effect of pelvic incidence (PI) on postoperative outcomes after hip arthroscopy for acetabular labral tears in the setting of FAI.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective query of prospectively collected data identified patients ≥18 years of age who underwent primary hip arthroscopy for FAI and acetabular labral tears between February 2014 and January 2022, with 3-, 6-, 12-, and 24-month follow-ups. Measurements for PI, pelvic tilt (PT), sacral slope (SS), and acetabular version were obtained via advanced diagnostic imaging. Patients were stratified into low-PI (<45°), moderate-PI (45°≤ PI ≤ 60°), and high-PI (>60°) cohorts. Patient-reported outcome measures (PROMs), clinically meaningful outcomes (ie, minimal clinically important difference, Patient Acceptable Symptom State, substantial clinical benefit, and maximal outcome improvement), visual analog scale (VAS) pain scores, and patient satisfaction were compared across cohorts.

RESULTS

A total of 74 patients met eligibility criteria and were stratified into low-PI (n = 28), moderate-PI (n = 31), and high-PI (n = 15) cohorts. Correspondingly, patients with high PI displayed significantly greater values for PT (P = .001), SS (P < .001), acetabular version (P < .001), and acetabular inclination (P = .049). By the 12- and 24-month follow-ups, the high-PI cohort was found to have significantly inferior PROMs, VAS pain scores, rates of clinically meaningful outcome achievement, and satisfaction relative to patients with moderate and/or low PI. No significant differences were found between cohorts regarding rates of revision arthroscopy, subsequent spine surgery, or conversion to total hip arthroplasty.

CONCLUSION

After hip arthroscopy, patients with a high PI (>60°) exhibited inferior PROMs, rates of achieving clinically meaningful thresholds, and satisfaction at 12 and 24 months relative to patients with low or moderate PI. Conversely, the outcomes of patients with low PI (<45°) were found to match the trajectory of those with a neutral spinopelvic alignment (45°≤ PI ≤ 60°). These findings highlight the importance of analyzing spinopelvic parameters preoperatively to prognosticate outcomes before hip arthroscopy for acetabular labral tears and FAI.

Three-Dimensional CT and 3D MRI of Hip- Important Aids to Hip Preservation Surgery

Common hip internal derangements include femoroacetabular impingement (FAI), developmental dysplasia of hip (DDH) dysplasia, and avascular necrosis (AVN) of the femoral head. These are initially screened by radiographs. For preoperative planning of hip preservation, 3-dimensional (3D) CT is commonly performed to assess bony anatomy and its alterations. Magnetic resonance imaging (MRI) is used to evaluate labrum, hyaline cartilage, tendons, synovium, and loose bodies, and provides vital information for surgical decision-making. However, conventional 2D MRI techniques are limited by lack of isotropic multiplanar reconstructions and partial volume artifacts. With advancements in hardware and software, novel isotropic 3D MR Proton Density images are acquired with acceptable acquisition times leading to improved visualization of soft tissue and osseous structures for various hip conditions. Three-Dimensional MRI allows multiplanar non-gap reconstructions along the structures of interest. It results in detection of small, otherwise inconspicuous labral tears without the need for MR arthrogram, which can be subsequently measured. In addition, radial reconstructions of the femoral head can be performed from original 3D volume MR imaging and CT imaging without the need for individual different plane acquisitions. Three-Dimensional MRI thus impacts surgical decision-making for the important common hip derangement conditions. For example, femoral head hyaline cartilage loss may make hip preservation difficult or impossible. In this review, we discuss the advantages and technical details of 3D CT and MRI and their significant role in aiding hip preservation surgery for common hip conditions. The conditions discussed in this article include FAI, DDH, AVN, synovial disorders, cartilaginous tumors, and hip fractures.

Changing Treatment Philosophy of Slipped Capital Femoral Epiphysis (SCFE) after Introduction of the Modified Dunn Procedure (MDP): Our Experience with MDP and Its Complications

BACKGROUND

The modified Dunn procedure (MDP) has become popular during the last 16 years to treat severely displaced slipped capital femoral epiphysis (SCFE) while "in situ" pinning (ISP) has remained valid to treat mild to moderate SCFE, although the indication limit of the Southwick angle (SA) has not yet been established for either procedure. In this context, we reviewed two cohorts of patients with SCFE, one treated by ISP and the other by MDP. We also tried to better elucidate the etiopathogenesis of hip instability, a severe complication of MDP.

METHODS

Fifty-one consecutive patients with 62 hips affected by SCFE were treated by us from 2015 to 2019: 48 hips with a SA ≤ 40° had ISP while 14, with the SA > 40°, had MDP. The latter also had a CT scan to better investigate the SCFE morphology. Results were assessed using the Harris Hip Score.

RESULTS

The mean length of follow up of the two cohorts was 5.4 years (range: 3 to 8 years). Of the 35 hips operated by ISP with a full follow-up evaluation, 30 had an excellent or good result, 3, fair, and 2, poor. Of the 14 hips that underwent MDP, 11 had an excellent or good result, 1, fair, and 2, poor. A CT scan showed femoro-acetabular incongruency in two unstable hips following MDP.

CONCLUSIONS

We performed ISP in chronic SCFE with the SA ≤ 40° and MDP in acute and chronic SCFE with the SA > 40°, with satisfactory results. In both acute-on-chronic and chronic long-lasting SCFE with severe displacement, planned for MDP, a CT scan should be carried out to evaluate possible femoro-acetabular incongruency that may cause hip instability.

Is combined surgical dislocation and proximal femoral osteotomy a safe procedure for correction of complex hip deformities?

Complex deformities of the hip requiring intra-articular and proximal femoral correction are challenging with regard to surgical access and complication risk. Combined surgical dislocation and proximal femoral osteotomy (SD/PFO) is a surgical strategy that provides unrestricted access to the joint with the capability for adjunctive PFO. Although providing excellent surgical access, concerns over a potentially high risk of postoperative complications remain, and published information on the safety of this technique remain scarce. In this study, we defined the early complication profile of combined surgery across 48 hips with a variety of complex deformities using a standardized, validated complication grading scheme for hip preservation surgery. Patients were mean age 19.1 years 13–33 years and 60% had previous surgery. At the early mean follow-up of 2.9 years, considerable improvement was seen across all outcome scores. Major complications (Grade III or higher) occurred at a rate of 4.2% (n = 2). Both were osteotomy non-unions, and both were treated successfully with revision PFO and bone grafting at mean 1.1 years. To our knowledge, the current series of combined SD-PFO surgeries represents the largest to date for which detailed complication data have been reported. Given the complexity of these disorders, a major complication rate of 4.2% is acceptable. Our complication rates were comparable to those reported for isolated SD and PFO procedures. These rates did not vary significantly across morphologic variants or patient-specific characteristics. Additionally, our complication risk profile is consistent with previous, smaller reports, which supports the generalizability of these results among appropriately experienced surgeons.

The Incidence of Hip Arthroscopy in Patients With Femoroacetabular Impingement Syndrome and Labral Pathology Increased by 85% Between 2011 and 2018 in the United States

PURPOSE

The purpose of this study was to investigate the incidence of hip arthroscopy in patients with labral pathology in the United States from 2011-2018 using a large national database.

METHODS

Patients who underwent hip arthroscopy from 2011-2018 were identified using Current Procedural Terminology (CPT) codes in the PearlDiver Patients Records Database (Colorado Springs, CO), which is a national database of orthopedic insurance records, including Medicare patients. The incidence of surgeries, age, and gender were all recorded. Groups were analyzed using SPSS version 24 (IBM, Armonk NY). CPT codes 29914/15/16 were introduced January 1, 2011 which is when we began our analysis. CPT-29999 and laterality were not assessed.

RESULTS

In total, 35,966 arthroscopies were identified between 2011 and 2018 from a randomly selected sample of 30 million orthopaedic patients from the PearlDiver Mariner dataset. The incidence increased by 85% from 2011 to 2018 (7.31 cases vs 13.54 cases per 100,000 patients). The distribution of the age of patients undergoing hip arthroscopy was bimodal with the mode of each peak at 18 years old and 42 years old, respectively. Females underwent surgery more frequently (67.9%) than males (32.1%). The most common CPT code for hip arthroscopy was 29914 (43.9) which corresponds to a hip arthroscopy with femoroplasty.

CONCLUSIONS

Our findings corroborate those of previous studies and support the increase in incidence of hip arthroscopy in the United States. We indicate an overall increase of 85% from 2011 to 2018 and support previous trends, such as higher incidence of hip arthroscopy in women. Our study also supports a decreasing mean age for patients, likely due to improved diagnostics and surgeon familiarity and comfort with the procedure.

LEVEL OF EVIDENCE

Level 3, Retrospective Comparative Study.

Utility of Ultrasound-Guided Anesthetic Intra-articular Injection to Estimate the Outcome of Hip Arthroscopy in Patients with Femoroacetabular Impingement Syndrome

Objective

To investigate the effectiveness of ultrasound (US) guided intra‐hip joint injection to estimate the outcome of hip arthroscopy in patients with femoroacetabular impingement (FAI) syndrome.

Methods

Patients with FAI syndrome (n = 60) were prospectively enrolled in our study. Before hip arthroscopy, a mix of 4 mL 2% lidocaine and 4 mL 1% ropivacaine were injected into the hip joint under the guidance of US. The clinical efficacy of the intra‐articular injection was evaluated by comparing the visual analog scale (VAS) and international hip outcome tool 12 (iHOT‐12) results before and after the injection. The outcome of hip arthroscopy was evaluated by iHOT‐12, the modified Harris hip score (MHHS), and the patient's satisfaction 12 months after the operation. The outcome of intra‐articular injection and hip arthroscopy were compared. Factors related to the outcomes of hip arthroscopy were evaluated. The correlation between the efficacy of intra‐hip joint injection and arthroscopy was evaluated.

Results

The VAS of patients decreased from 11.3 ± 7.7 to 3.3 ± 4.5, and the iHOT‐12 increased from 52.1 ± 23.2 to 84.1 ± 18.1 after intra‐articular injection (all P < 0.001). The iHOT‐12 score increased from 52.1 ± 23.2 to 78.9 ± 19.2, and the MHHS increased from 66.5 ± 6.8 to 81.6 ± 8.1 after hip arthroscopy (all P < 0.001). The satisfaction rate of arthroscopy, including very satisfied and effective patients, was 93.3%. Multi‐variable logistic regression showed that only iHOT‐12 improved value after injection was included in the regression formula of satisfaction, with the β of −0.154, standard error of 0.071, Wald value of 4.720, and OR of 0.857 (95%CI 0.746–0.985) (P = 0.03). Significant correlation was detected between iHOT‐12 scores after intra‐articular anesthesia and at 12 months after arthroscopy (r = 0.784, P < 0.001). So was the iHOT‐12 improved value (r = 0.781, P < 0.001) and the iHOT‐12 improved ratio (r = 0.848, P < 0.001). If we had performed arthroscopy only on patients with post‐injection iHOT‐12 score improvement ≥10, the satisfaction rate of arthroscopy would have increased to 96.6%.

Conclusions

US‐guided intra‐hip joint injection may provide a feasible way to estimate the outcome of hip arthroscopy in patients with FAI syndrome, and could be used as a method for indication selection of hip arthroscopy.

Outcomes After Arthroscopic Osteochondroplasty for Femoroacetabular Impingement Secondary to Slipped Capital Femoral Epiphysis: A Systematic Review

PURPOSE

To determine the efficacy of arthroscopic osteochondroplasty for patients with femoroacetabular impingement (FAI) secondary to slipped capital femoral epiphysis (SCFE).

METHODS

A systematic review was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using Embase, PubMed (Medline), and Cochrane Library up to November 1, 2019. Data including patient demographics, slip severity according to Southwick, outcomes, and complications were retrieved from eligible studies that reported a minimum 3-month follow-up of arthroscopic osteochondroplasty for FAI secondary to SCFE. Methodological Index for Non-Randomized Studies (MINORS) criteria was used to assess quality of studies. Heterogeneity and quality were evaluated using P values and the I² statistic.

RESULTS

Six studies (90 hips) were analyzed. The range of MINORS scores was 8 to 11. Most studies were level of evidence 4 (n = 4, 66.7%), with more men than women (n = 5, 83.3%). The ranges of age, body mass index, and follow-up length after surgery were 10 to 42 years, 17.5 to 32.3 kg/m², and 3 to 56 months, respectively. The Modified Harris Hip Score (mHHS) was the most commonly used score to report on clinical outcomes (n = 2 studies, 28 hips) with a significant improvement following surgery. Three studies reported an improvement in internal rotation (IR) of the hip with a range of improvement of 17° to 32°, with low heterogeneity (I² = 0% and P = .531). Five studies reported a significant correction of the α angle, with range of improvement of 19.9° to 37.3°. The range of postoperative α angle was 32° to 67°, and 3 studies achieved appropriate postoperative α angle (40° to 50°), with low heterogeneity (I² = 8.4% and P = .336). The total number of complications was 8 (1 major complication) and there were 6 revisions, with low heterogeneity.

CONCLUSION

Arthroscopic osteochondroplasty for FAI secondary to SCFE provides good short- to medium-term outcomes and improves IR of the hip, with the ability to potentially correct the α angle with a low rate of complications and revision.

LEVEL OF EVIDENCE

IV, systematic review of level II to IV studies.

Increased hip arthroscopy operative duration is an independent risk factor for overnight hospital admission

PURPOSE

The purpose of this study was to determine the association between operative duration and short-term complications as well as overnight hospital admission following hip arthroscopy.

METHODS

Hip arthroscopy cases from 2006 to 2016 were retrieved from the National Surgical Quality Improvement Program registry, which prospectively collects 30-day postoperative complications. Patients were stratified into the following groups based on procedure length: group 1 (< 60 min), group 2 (60-120 min), and group 3 (> 120 min). Preoperative characteristics were compared across the cohorts. Multivariate regressions were used to compare complication rates and overnight hospital admission between the three groups. Independent risk factors for overnight hospital admission were characterized.

RESULTS

A total of 2129 hip arthroscopy cases were identified. Average operative duration was 99.3 ± 55.7 min. As operative time increased, patients were more likely to be younger, male, and had lower American Society of Anesthesiologists (ASA) class (p < 0.001). Body mass index and comorbidity profiles were similar across the patient cohorts, with the exception of hypertension being more prevalent in the shorter operative time cohort (p < 0.001). Patients in group 3 were more likely to stay overnight in the hospital (26.0%) compared to patients in groups 1 (7.7%) and 2 (10.9%), p < 0.001). All postoperative complication rates were otherwise similar between the cohorts. Independent risk factors for overnight hospital admission included increasing operative time (most notably > 120 min relative to < 60 min, relative risk [RR] = 3.53, 95% CI 2.50-5.00, p < 0.001) and increasing ASA classification (most notably ASA III or IV relative to ASA I, RR = 1.64, 95% CI 1.18-2.27; p = 0.013).

CONCLUSIONS

Increasing operative duration was not associated with increased postoperative complications following hip arthroscopy. However, patients were more than three times likely to stay in the hospital overnight if their surgery was longer than 120 min, relative to cases that were less than 60 min.

LEVEL OF EVIDENCE

III.