Femoroacetabular Impingement: Critical Analysis Review of Current Nonoperative Treatments

Abstract

• »Femoroacetabular impingement (FAI) is the premature contact of the femoral head-neck junction with the superior acetabular rim during hip range of motion, which may further damage intra-articular soft tissue structures and lead to the accelerated development of osteoarthritis.
• »FAI syndrome is diagnosed by a triad of symptoms, clinical signs, and imaging findings, and is a common cause of hip pain in young patients that have a significant impact on patient hip-related function and quality of life.
• »The treatment of FAI syndrome begins with noninvasive nonoperative modalities such as patient education and supervised exercise-based physical therapy. For recalcitrant symptoms, various injections have been explored for both diagnostic and therapeutic purposes; however, the efficacy of these interventions have generally not been demonstrated outside of the short term
• »In this article, we examine the available literature regarding the nonoperative treatment of FAI and provide insight into the effectiveness of current treatment modalities.

Femoroacetabular impingement (FAI) is the premature contact of the femoral head-neck junction with the superior acetabular rim during hip range of motion¹. Within the last few decades, the condition has been identified as a common cause of hip pain, particularly among young active patients². FAI is associated with morphologic changes about the proximal femur and/or acetabulum. In cam morphology, there is bony overgrowth about the femoral head-neck junction, causing an aspherical shape. Pincer morphology exhibits the bony overgrowth about the acetabular rim, thereby increasing femoral head coverage. Whether these morphologies occur in isolation, or in tandem, there is resultant impingement, most commonly about the anterosuperior joint with hip range of motion (particularly with flexion and internal rotation), which may further cause structural damage to the adjacent labrum and acetabular cartilage³. While cam and/or pincer morphology may be observed in a reported 30% to 60% of the general population, less than a fourth these individuals become symptomatic^4,5. Therefore, according to the 2016 international consensus statement, FAI syndrome is defined by a triad of symptoms, clinical signs, and imaging findings¹.

While a large percentage of patients with abnormal morphology remain asymptomatic, FAI syndrome can have a significant impact on patient hip-related function, quality of life, and risk of osteoarthritis development^6,7. Although a definitive treatment algorithm for FAI syndrome has yet to be delineated, the use of joint-preserving surgery (i.e. hip arthroscopy, surgical dislocation, periacetabular osteotomy) to address the osseous impingement and the resultant periarticular structural damage has increased over the last 2 decades^1,8. However, the consensus remains that first-line treatment for most patients should be nonsurgical intervention, as conservative management has been found to effectively reduce symptomaticity, improve outcome measures, and delay need for surgical intervention without compromising its outcomes should it eventually be indicated^9-14. In the present review, we comprehensively examine current literature on nonoperative FAI management to provide supplemental familiarity on the efficacy of current therapies (Table I).

TABLE I.

Recommendations for Care in Nonoperative Management of FAI

Clinical Care Recommendation	Grade of Recommendation*
Patient education, and exercise-based physical therapy and rehabilitation should be considered first-line treatment for symptomatic FAI	A
Hyaluronic acid injections appear to confer reliable short-term improvements in hip pain and function for symptomatic FAI. Potential intermediate-term and long-term benefit has not yet been demonstrated	B
Corticosteroid injections may provide variable short-term relief for FAI syndrome, but do not provide intermediate or lasting relief, and recurrent injections may be contraindicated in the setting of healthy cartilage	B
Other biologic injections such as platelet-rich plasma or BMAC have demonstrated potential to augment surgical management of FAI, but have not yet been investigated as viable nonoperative interventions	I

BMAC = bone marrow aspirate concentrate, and FAI = femoroacetabular impingement

^*According to Wright⁸⁵, grade A indicates good evidence (Level-I studies with consistent findings) for or against recommending intervention; grade B, fair evidence (Level-II or III studies with consistent findings) for or against recommending intervention; grade C, poor-quality evidence (Level-IV or V studies with consistent findings) for or against recommending intervention; and grade I, insufficient or conflicting evidence not allowing a recommendation for or against intervention.

Diagnosis, Risk Factors, and Demographic Epidemiology

The most common reported symptoms of FAI are position-dependent hip and groin pain (i.e. sitting or deep squat), subjective stiffness, or activity-related mechanical symptoms such as catching, locking, or give-way. Patients may classically demonstrate a “C-sign” with their hands when attempting to demonstrate the location of their pain, spanning the anterior groin to the lateral aspect of the greater trochanter. Pain may also be experienced along the back, buttock, or thigh. On physical examination, patient hip range of motion may be limited, with pain and obligate external rotation observed on maximal hip flexion^1,15. Provocative testing such as the hip flexion, adduction, and internal rotation (FADIR) maneuver may reproduce groin discomfort, although its sensitivity and specificity for FAI is low^16-18. Hip strength, single-leg stance capability, and proprioception may also be impaired relative to the contralateral side¹⁹.

FAI may be identified on hip radiographs with the use of anteroposterior (AP), cross-table lateral, and modified Dunn views. A variety of radiographic measurements have historically been used to characterize FAI, but most often an alpha angle >50 to 60° is used to define cam morphology and a lateral center-edge angle exceeding 40° to define pincer morphology^20-23. Pincer morphology is commonly associated with acetabular retroversion, and this too may be identified on AP-view radiographs, denoted by the pathognomonic “crossover” sign³. Advanced imaging in the form of computed tomography or magnetic resonance imaging (MRI) may be used to further characterize bony morphology or assess for concomitant labral and cartilaginous damage about the joint, respectively.

FAI syndrome has a reported overall incidence rate of 54 per 100,000 person-years, with peak incidence of diagnosis from 18 to 35 in women and 19 to 25 in men⁸. Overall, cam lesions are more prevalent in men, accounting for approximately 37% of morphologies^3,5. Pincer morphology is more commonly described in women, accounting for 67% of morphologies²⁴. Mixed-type morphology is more common than either in isolation. As cam lesions are more commonly observed in athletic populations, it has been postulated that their development may be related to volume and intensity of exercise during skeletally immaturity, particularly through repetitive injury to the proximal femoral physis, such as may be experienced with high-impact sports⁵. By contrast, the etiology of pincer morphology remains unknown, with similar rates observed among athletic and nonathletic populations²⁵. Furthermore, the abnormal joint mechanics cause damage to surrounding soft tissue and cartilaginous structures. As a result, cam-specific FAI has been implicated in the development of primary hip osteoarthritis in as high as 25% to 50% of patients with observed degenerative changes^26-30.

Treatments

Patient Education, Exercise-Based Physical Therapy, and Rehabilitation

FAI has been shown to have substantial implications on native hip biomechanics. Namely, patients with FAI demonstrate restricted hip range of motion, diminished functional strength and proprioceptive capability, and reduced periarticular muscle bulk when compared with healthy controls^19,31-35. As such, patient education and implementation of a supervised physical therapy protocol to address these muscular imbalances and promote accommodative functional movement patterns has been a mainstay of conservative treatment. Evaluation and treatment by a licensed therapist has been found more effective than completion of a home-exercise regimen alone^36,37. Within daily life, patients are advised to avoid positions and postures known to exacerbate FAI symptoms—specifically FADIR, cross-legged sitting, prolonged static postures, deep squats movements, and side-to-side pivoting³⁸. Following assessment of patient symptoms and hip-related and functional deficits, an individualized physical therapy and exercise program should be tailored with a goal of improving pain, range-of-motion, neuromuscular control, and strength³⁹. Therapists may further intervene to correct postural deficits—such as swayback and anterior pelvic girdle tilt—which are observed more frequently within patients with FAI, as well as incorporate core strengthening in addition to hip-focused exercises, as their inclusion has been associated with improved functional outcomes in these populations^40-42.

The effectiveness of physiotherapy and rehabilitation in improving pain and function in patients with FAI has been well documented. Kemp et al. demonstrated that the employment of a 12-week physical therapy program incorporating hip and core strengthening alongside patient education significantly improved hip pain and functional outcomes in patients with FAI compared with controls (international Hip Outcome Tool-33 [iHOT-33])⁴³. Furthermore, in their 2019 investigation, Aoyama et al. found that implementation of a core strengthening and trunk stabilization program within patients with FAI conferred significant improvements in hip flexion range of motion, hip-abduction strength, and Vail hip and iHOT12 scores at 4 weeks and 8 weeks postintervention compared with controls⁴². A recent meta-analysis of 5 randomized controlled trials (RCTs) incorporating 124 patients with FAI (mean age 35 years; average follow-up 9.4 weeks) by Hoit et al. found that hip and core strengthening protocols, active physiotherapy, and supervised physiotherapy conferred statistically significant improvements in patient-reported functional outcomes compared with patients who underwent no core strengthening, passive modalities, and unsupervised care, respectively⁴¹.

In a prospective study investigating utilization of a nonoperative protocol in 76 adolescent patients with FAI (mean age 15.3 years), Pennock et al. found that 70% of patients were successfully managed by formal physical therapy, rest, and activity modification alone—evidenced by exceeding the minimal clinically important difference in modified Harris Hip Score (mHHS), significant improvement in the Nonarthritic Hip Score (NAHS), and avoidance of progression to surgical intervention across 2-year follow-up¹⁰. With use of the same cohort, a subsequent 5-year follow-up study revealed that these significant improvements in patient-reported outcomes were maintained at the midterm, with no significant drop-off in mHHS or NAHS (p > 0.3), and only 1 patient progressing to surgery between the 2-year and 5-year time periods¹³. Monn et al. similarly investigated midterm outcomes following implementation of physiotherapy protocol in 26 symptomatic patients with FAI and found at the mean 4.6-year follow-up, 19 of 26 patients had not progressed to surgery; Hip Outcome Score (HOS)-Activity of Daily Living (ADL) and HOS Sport outcome scores were significantly higher than pretherapy and comparable with scores documented at 18-week follow-up. Furthermore, patient Hip Sports Activity Scale (HSAS) scores were significantly lower at the final follow-up than their presymptomatic status (p = 0.022) but were comparable with their scores at 18-week follow-up, suggesting maintenance of the good exercise therapy outcomes and level of sport activity achieved in the short-term, at midterm follow-up⁴⁴.

Collectively, these studies suggest that patient education and supervised physical therapy can provide significant improvements in hip pain and function in the short-term and midterm for patients with symptomatic FAI. There is, however, a paucity of high-quality investigations exploring midterm and long-term outcomes following this intervention, highlighting the need for future studies to be conducted.

Injections

Injections may serve as both diagnostic and therapeutic tools in the management of FAI.

Corticosteroid Injection

Corticosteroid injections (CSIs) have long been used in the setting of intra-articular pathology given their ability to modulate inflammatory indices and suppressive nociceptive pathways within musculoskeletal disease pathways⁴⁵. Several studies have investigated their usefulness within the setting of FAI. Krych et al. prospectively investigated the use of a single image-guided intra-articular corticosteroid with local anesthetic injection in 54 patients with radiographic evidence of FAI and no concomitant osteoarthritis (Tonnis grade 0 or 1). Although mean Numerical Rating Scale (NRS) pain scores decreased from 7.0 preinjection to 1.0 during the immediate anesthetic phase, pain scores rebounded to 5.0 by 2 weeks postinjection, representing a significant diminishment of pain relief from the postinjection anesthetic phase (p < 0.001). Furthermore, at 14-days postinjection, only 37% of patients reported clinically significant decrease in pain; this further decreased to 6% by the 6-week mark, with an average duration of pain relief of 9.8 days. Altogether, their findings suggested short-lived benefit from steroid injections alone within FAI populations^46-48. The 2016 systematic review by Khan et al. investigated the utility of various intra-articular hip injections for FAI. The pooled results of 8 studies involving 281 hips, further reveals poor duration of treatment efficacy, as only 15% (9/60) of patients experienced symptom improvement at 6 weeks following CSI⁴⁹.

These findings were somewhat contrasted by those of Ebert et al., who recently reported on 44 patients who received a single image-guided CSI in the setting of symptomatic and radiographic-verified FAI with low-grade osteoarthritic changes. Differing from the aforementioned study, participants in this investigation subsequently underwent an 8-week supervised physical therapy and rehabilitation protocol. Investigators found that while 14/ of 44 patients (31.8%) progressed toward surgical intervention by the time of 2-year follow-up, those who remained within the nonoperative cohort demonstrated a 93% overall satisfaction rate, and significant increase in all hip range of motion, most isometric strength measures, and patient-reported outcome measures (iHOT-33 and HOS-ADL) both at 8 weeks and at the final 2-year follow-up (p < 0.05). Of note, those who progressed toward surgery had significantly worse iHOT-33 and HOS-ADL scores preinjection, and by as early as 1 week postinjection, they had already reported significantly worse pain than the cohort who remained nonoperative throughout the study. This suggests that initial symptom severity may influence the ultimate effectiveness of the intervention⁵⁰.

Collectively, these studies point to CSI as a relatively noninvasive intervention that may offer short-term relief of FAI symptoms, particularly when paired with an exercise-based rehabilitation program. The duration of benefit remains questionable, however, and the results may also vary based on preexisting symptomaticity. Notably, there is also potential morbidity associated with this intervention. As with the introduction of any foreign substance into the joint, there is potential for the development of septic arthritis, and as well as the possible cumulative chondrotoxic effect associated with multiple (or even single) CSIs. Therefore, appropriate caution is warranted against repeat steroid injections in the setting of healthy cartilage^51-56.

Hyaluronic Acid Injection

The efficacy of viscosupplementation by intra-articular hyaluronic acid (HA) injections has also been investigated in the setting of FAI syndrome, given their demonstrated benefits in the treatment of symptomatic osteoarthritis⁵⁷. The effects of HA have been ascribed to its protective action on articular cartilage and soft tissue, as well as its anti-inflammatory properties^57,58. Abate et al. conducted a prospective trial in which 23 hips (20 patients) with radiographically confirmed FAI syndrome without concomitant OA underwent a series of 4 intra-articular HA injections. An initial injection was administered at baseline and another at 40 days, and the same dosing schedule was then repeated 6 months later. Clinical evaluation was performed at preinjection baseline, at 6 months, and at final 12-month follow-up with the use of a 10-point VAS pain score, Lequesne Index, Harris Hip Score (HHS), and anti-inflammatory medication consumption. Investigators reported a significant decrease in pain from baseline to 6-month follow-up (6.7 vs. 3.7), reduction in Lequesne Index from baseline to 12-month follow-up, improvement in HHS from baseline to 12-month follow-up (83.3 vs. 88.2), and reduction in anti-inflammatory drug consumption (14 patients vs. 4 patients; 3.6 vs 1.3 tablets per week). There was an additional significant improvement in VAS pain scores from 6-month to 12-month follow-up (3.7 vs. 1.7). Overall, the intervention was very well tolerated, with only 2 patients reporting mild temporary side effects (pain, heat, redness) lasting less than 3 hours following injection. Of note, none of the patients progressed to surgical intervention by the time of final 12-month follow-up⁵⁹.

In their 2016 randomized double-blinded crossover study, Lee et al. compared the effectiveness of HA and CSI in 30 patients with radiographically confirmed FAI syndrome without concomitant hip OA. Patients were received either CSI (triamcinolone acetate) or HA injection at baseline, with subsequent crossover injection at 2 weeks in those without reported clinical response or decrease in pain intensity (<2 points change measured by 10-points NRS). At 2-week follow-up, the HA group was found to have significant improvement in Hip Disability Scores (HOOS), without significant improvement in NRS pain scores; in contrast, the CSI group was found to have significant improvement in NRS pain scores, without improvement in HOOS scores (mean increase of HOOS = 13.8 with HA vs. −2.2 with TA, p = 0.031; mean decrease of NRS = 1.7 with first TA vs. 0.3 with first HA, p = 0.036). Thirteen patients subsequently underwent crossover at 2 weeks, and at 4-week follow-up, all cohorts demonstrated significant improvement in both NRS pain score and HOOS functional scores; however, those who underwent CSI first continued to endorse significantly better NRS scores than those who underwent HA first, while those who underwent HA first demonstrated significantly better HOOS scores than those who received CSI initially (NRS: 0.9 with TA first and HA later vs. 2.7 with HA first and TA later, p = 0.001; mean increase of HOOS: 5.3 with TA first and HA later vs. 10.2 with HA first and TA later, p = 0.032). While the large majority of patients were unable to follow-up by the conclusion of the 12-week study period, these findings suggest that HA may confer delayed and perhaps sustained improvement in function in patients with symptomatic FAI, while CSIs may provide initial pain relief more quickly⁶⁰.

The notion of sustained benefit from HA in the setting of FAI was further supported by the aforementioned 2015 systematic review by Khan et al. that reported intra-articular HA injection were most effective in providing pain relief and demonstrated significant improvements in functional outcomes that remained evident at 12 months postinjection⁴⁹. Altogether, these investigations suggest HA injection exists as a well-tolerated nonoperative intervention for improving pain and hip function in the setting of FAI, with effects that can persist throughout the short term. Notably, the study designs, injection formulations, and populations among which the intervention was used were heterogeneous, limiting conclusions that can be drawn. Further research is certainly needed to elucidate whether relief may persist throughout the short-term and long-term, as well as to determine the ideal HA injection formulations and demographics that would best benefit from it. As hip intra-articular HA injection is currently an off-label physician directed use of the medication, future investigations demonstrating its efficacy within the setting of symptomatic FAI could support its eventual consideration for Food and Drug Administration approval.

Platelet-Rich Plasma Injection

Platelet-rich plasma (PRP) has also been explored as an injectable agent for the treatment of intra-articular hip disorders^61,62. To our knowledge, there have hitherto been no investigations demonstrating the efficacy of PRP strictly in the setting of FAI syndrome before surgical intervention, although several studies have been conducted on outcomes when these injections were used concurrently alongside arthroscopic cam/pincer decompression with or without labral repair. Generally, these investigations and systematic reviews have found no association between PRP and improved outcomes when it was used as an adjuvant intraoperatively or postoperatively^62-70. In a solitary 2015 prospective study evaluating the clinical and immunologic effects of intra-articular doses of PRP in arthroscopic hip surgery for FAI, Rafols et al. randomized 57 patients to either receive or not receive an intra-articular injection of PRP at the end of surgery and followed patient outcomes for 24 months after surgery. Investigators found the PRP group reported lower postoperative pain scores at 48 hours (3.04 vs. 5.28 via Visual Analog Scale; p < 0.05) and lower rates of joint effusion (21.1% vs. 36.7%; p = 0.013) on 6-month follow-up MRI, but no difference in function through mHHS and no difference in MRI-assessed labral integration rates between the 2 groups⁷¹. In another small pilot study, De Luigi et al. administered intra-articular PRP to 8 patients who had previously failed conservative management for symptomatic labral tears and found significant improvement in VAS pain and HHS at 2 weeks, 6 weeks, and 8 weeks postinjection⁷². Of note, however, while labral tears are often sequelae of FAI, it was not specified whether these patients had concomitant FAI morphology. Altogether, there is a paucity of information available surrounding the efficacy of PRP injection in the nonoperative management of FAI. While studies conducted thus far demonstrate benefits for various intra-articular hip pathology and that it is not helpful as an adjunct to arthroscopic surgery for FAI, there is a need for high-quality investigations on its use before surgical intervention.

Bone Marrow Aspirate Concentrate Injection

Bone marrow aspirate concentrate (BMAC) is a product derived from autologous bone marrow containing mesenchymal stromal cells (MSCs), platelets, red and white blood cells, and a vast array of growth factors and cytokines produced by the cells therein. In addition to the known anti-inflammatory capabilities of BMAC, the multipotent MSCs have demonstrated ability to differentiate into cells that could potentially deter chondral damage, thereby sparking recent interest in its potential use for intra-articular hip pathology. Similar to PRP, to our knowledge, no studies have been conducted expressly investigating the use of BMAC within the setting of nonoperative or preoperative management of FAI specifically. However, 2 recent prospective cohort studies have compared outcomes for hip arthroscopy with or without intraoperative augmentation with BMAC. In their 2022 investigation composed of 124 patients who underwent arthroscopic labral repair either with (n = 62) or without (n = 62) BMAC augmentation, Martin et al. reported that while there were no significant differences overall between the augmentation and nonaugmentation group at any time point during the 2-year follow-up, among patients specifically noted to have moderate intra-articular chondromalacia at the time of surgery, there were significantly greater iHOT-33 functional scores at 12-month (78.6 vs. 69.2; p = 0.035) and 24-month (82.5 vs. 69.5; p = 0.030) follow-ups with augmentation⁷³. Similarly, in their 2020 study, Rivera et al. performed hip arthroscopy for 80 patients with FAI, in which half patients received intraoperative augmentation with BMAC⁷⁴. The investigators found that at 12-month and 24-month follow-ups, the augmentation group demonstrated significantly lower VAS pain scores (0.007), higher mHHS scores (0.004), and higher iHOT scores (p = 0.024). Together, these studies suggest a potential role for BMAC in the surgical management of FAI; however, high-quality investigations are warranted to determine whether this product could be useful in its nonoperative management as well.

Hip Arthroscopy vs. Conservative Management

Surgical management of FAI is generally reserved for cases refractory to the aforementioned conservative measures and typically entails arthroscopic femoroplasty, acetabuloplasty, and labral repair^75-77. Improved postoperative outcomes regarding pain and hip function and decreased risk of subsequent THA have been observed among patients with symptomatic FAI treated within 3 to 6 months of symptom onset compared with those with longer symptom duration before surgical intervention^78,79, suggesting the need to alter FAI treatment strategy within a timely fashion if clinical improvement is not observed with conservative measures alone^80-82. In addition, given persistent large cam-type lesions have been associated with the expedited development of end-stage hip osteoarthritis^26,30, and the observed stepwise decline in postoperative outcomes as patient age at the time of surgery increases, contemporary literature also supports an individualized approach to consideration for surgical candidacy, where more prompt operative intervention could be considered for young patients demonstrating substantial morphologic changes alongside significant hip range of motion deficits and/or evidence of early chondrolabral damage (Fig. 1).

Fig. 1.

Preoperative (top) and postoperative (bottom) Dunn view radiographs of a 19-year-old patient with significant cam deformity and concomitant hip stiffness who underwent expedited hip arthroscopy for femoroplasty, acetabuloplasty, and labral repair.

Several recent RCTs have directly compared outcomes from conservative vs. surgical management of FAI. The first was a 2018 multicenter RCT (UK FASHIoN study), in which Griffin et al. allocated 348 participants with radiographically confirmed symptomatic FAI without concomitant OA to undergo either hip arthroscopy or personalized hip therapy for management. Personalized hip therapy entailed a 12-week to 24-week individualized and supervised physiotherapist-led program of conservative care that also permitted a single image-guided CSI should the patient require it for analgesic relief to complete the protocol. At the time of 12-month final follow-up, while both groups demonstrated significant improvement in hip pain and function, the hip arthroscopy group had greater statistically significant improvement on iHOT-33 scores compared with the conservative group (39.2-58.8 vs. 35.6-49.7, respectively; p = 0.0093)⁸⁰. In the 2021 Australian FASHIoN trial, Hunter et al. used a similar protocol and likewise found statistically significant improvement among both operative and nonoperative groups at the 12-month final follow-up, but with statistically significant and clinically important greater improvement in the arthroscopy group of 14.2 units on iHOT33 (p = 0.003)⁸¹. Palmer et al. further investigated personalized supervised physiotherapy (without offering need-based CSI) vs. hip arthroscopy in a 2019 multicenter RCT involving 222 participants and reported mean HOS-ADL scores 10.0 points higher in the arthroscopy group compared with the physiotherapy program group (p < 0.001) at 8-month follow-up⁸².

In contrast to the aforementioned findings, Mansell et al. reported no significant differences between groups in HOS and iHOT-33 scores with 2-year follow-up in their 2018 RCT comparing supervised physiotherapy vs. arthroscopic management of symptomatic FAI among 80 active-duty military personnel. Of note, 28 patients (70%) initially allocated to the physiotherapy arm crossed over to surgery during the study period, and all surgeries were performed by a single surgeon at one hospital⁸³. A recent meta-analysis including all of the aforementioned studies (total 6 RCTs including 1,187 patients) did find that while arthroscopic and conservative therapies both have statistically significant clinical effects in the treatment of FAI, hip arthroscopy was statistically superior to conservative treatment at 1-year follow-up⁸⁴.

Altogether, the contemporary body of evidence supports the notion that FAI patients with hip pain and functional deficits refractory to conservative treatments could potentially benefit from arthroscopic surgery. However, heterogeneity among study populations, variable treatment protocols, and follow-up periods limited to the short-term highlight the need for future longitudinal multicenter RCTs to be conducted.

Conclusion

Nonoperative management of FAI syndrome remains the first-line treatment in one of the most common sources of hip pain in young patients. Contemporary evidence demonstrates that physical therapy and rehabilitation offers reliable short-term and midterm therapeutic benefits for patients with FAI syndrome, with little-to-no morbidity. CSIs may confer short-term symptomatic relief, particularly when paired with physiotherapy, but variable effectiveness and potential deleterious effects on healthy cartilage make it a less favorable repetitive long-term treatment option. Biologic injections have also been used in the treatment of FAI. While HA injections demonstrate the potential to provide prolonged improvement in hip pain and function, PRP injections are still very early in their investigational phase, with insufficient evidence to definitively recommend for or against treatment. As the large majority of studies conducted thus far include only short-to-intermediate term follow-up, future RCTs are warranted to investigate the long-term effectiveness of these nonoperative treatment adjuncts and refine the criteria for recommending early operative intervention in specific patient characteristics.

Source of Funding

No external source of funding was utilized for this investigation.