Diagnosis and non-surgical options for Femoroacetabular Impingement
Ross Hauser, MD
Surgery and non-surgical options for Femoroacetabular Impingement
In this article, we will tackle the problems of getting an accurate diagnosis and appropriate treatment options for Femoroacetabular Impingement (FAI). We will also present discussions that a problem of pain and function of Femoroacetabular Impingement can be addressed with treatments that focus on the soft tissue of the hip and low back. We will also focus on treatments that would help prevent bone spurs from developing in the ball and socket hip joint.
Femoroacetabular Impingement or sometimes diagnosed simply as Hip Impingement is a condition where abnormal contact and rubbing of the ball and socket portion of the hip bones creates joint damaging friction. For some people, the rapid degeneration of the hip joint causes the formation of bone spurs. The bone spurs are there because the body is trying to create stability in a joint that has become unstable. The loss of stability can be traced to a weakening of the ligaments and tendons of the hip, low back, groin, and hamstring areas, and hip labrum degeneration. Femoroacetabular impingement (FAI) is most often seen in young, active individuals who utilize their hip joints more vigorously than less active and middle-aged individuals, although FAI can occur in anyone who has the bony anomalies associated with the condition. There is some debate in traditional medicine as to whether FAI is a genetically inherited condition or due to abnormal formation of the hip bones during the childhood growing years, but the prevailing consensus is turning toward the latter theory.
In the minds of some athletes/runners, the bone spur formation at the ball and socket of the hip are the big problem. These runners think the best way to treat bone spur formation is with surgery to shave them off. But is that the best way? Or is it the best way for everyone?
Before we begin this article and research findings, if you would like to contact our medical team, please use our contact form page. We can help assess your candidacy for our treatments and answer your questions.
What are we seeing in this image?
In this illustration, hip instability caused by injury to the hip labrum or any of the hip ligaments typically causes the two main types of femoracetabular impingement – the pincer type and the CAM type. Prolotherapy addresses the hip and ligaments injuries or damage and can help resolve the hip pain issue.
- Femoroacetabular Impingement may only be one part of a bigger problem
- Surgery or anti-inflammatories? Some patients will manage themselves along as best they can, for as long as they can with the help of painkillers and anti-inflammatories. Probably like you.
- I can’t sleep because of my hip, stress, worry, thinking about surgery, no surgery, and I have a lot of pain.
- Opioids before hip arthroscopy surgery, opioids after hip arthroscopy
- Stopping the progress of Femoroacetabular Impingement – non-surgically. Femoroacetabular Impingement and Hip Instability
- Is it Femoroacetabular impingement causing your issues or is it something else?
- Is your MRI showing you what is causing your problems?
- If you have a scan or MRI of your hip showing femoroacetabular impingement, doctors are saying it may as well be worthless. That is a powerful statement, here is some powerful research
- Is it Femoroacetabular impingement causing your issues or do you have hip tendinopathy and Greater trochanteric pain syndrome?
- Is it Femoroacetabular impingement causing your issues or is it pelvic or lower back issues?
- The problem of pelvic tilt in Femoroacetabular impingement.
- Doctors are noting that one of the main causes of Femoroacetabular impingement is hip arthroscopic surgery.
- Compromised hip cartilage after surgery.
- Kinesiophobia and Pain Catastrophizing in Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome.
- Sports hernia and femoroacetabular impingement in athletes.
Femoroacetabular Impingement may only be one part of a bigger problem
Femoroacetabular impingement can be asymptomatic and not affect function or quality of life. But for those who become symptomatic, the likelihood is high that FAI will progress unless treated. FAI results from femoral and acetabular incongruity that induces labral, and chondral damage, purported to cause pain and restriction of motion, especially internal rotation and flexion. Patients may complain of pain with walking, tying their shoes and inability to exercise and play the sports they love. Early diagnosis is essential in order to arrest the progression of damage caused by FAI according to the orthopedist theory.
As in the many conditions we see, Femoroacetabular Impingement is not a condition or diagnosis that sits in isolation. It is typically part of a bigger picture of hip instability. A December 2019 published case history (1) examined the role of microinstability of the hip and the many simultaneous conditions it can lead to. What is described herein in this Canadian medical journal is very similar to the problems we have seen in the past 29 plus years. The case surrounds a 25-year-old female athlete who was able to avoid surgery with an exercise program. Here is the case:
The case surrounds a 25-year-old female athlete who was able to avoid surgery with an exercise program.
“This case is designed to aid practitioners in understanding the potential role of hip microinstability as a possible underlying source of hip pain and dysfunction. A 25-year-old female collegiate cross-country athlete presented with a 2-year history of progressive left hip and groin pain. Extensive clinical examination and imaging confirmed the presence of cam-type femoroacetabular impingement, a labral tear, and gluteal tendinopathy. Despite multiple intra and extra-articular (conditions), understanding the role of hip instability and implementing a rehabilitation exercise program focused on hip joint centration (exercises that hold the hip joint in its proper alignment and position) alleviated the patient’s symptoms at rest and during activity.
A robust history and physical exam of the hip is essential with the addition of imaging when testing criteria is positive. Clinicians should be aware of the role hip microinstability plays and its clinical implications when in the presence of other contributing factors such as generalized joint laxity, and/or intra-articular pathology.”
For some people, exercise programs that get the hip back into its natural and optimal position will work very well. For those it does not, we will present the information below on regenerative medicine injections that can accelerate the healing process.
These are options to the traditional treatments of prolonged anti-inflammatory use and possibly the eventual need for surgical repair.
Surgery or anti-inflammatories? Some patients will manage themselves along as best they can, for as long as they can with the help of painkillers and anti-inflammatories. Probably like you.
For many athletes/runners, surgery is a concern. Rather than have the surgery, some patients will manage themselves along as best they can, for as long as they can with the help of painkillers and anti-inflammatories. Most of these people will continue to exercise or run through dull constant pain. For some patients we see, running has now become difficult at best for them. Even as they admit to using over-the-counter anti-inflammatories. These patients tell us that nowadays their run will usually end when the pain becomes too much to handle and running turned into limping.
These patients are reaching the end of their ability to self-manage. These people see surgery as the only way. They are in our clinic as possibly the last stop in an attempt to find non-surgical relief.
I can’t sleep because of my hip, stress, worry, thinking about surgery, no surgery, and I have a lot of pain.
Very common in patients with any type of pain is the problem of getting good sleep. You probably did not need to be told this. Sleep problems, fatigue, and always being tired may be a deciding factor in waiting for a surgical date. Of course, you may have to increase medications to get you to your future surgery. In this article, we hope to present options and research that will help you today. The quicker you can successfully treat Femoroacetabular Impingement, even if the initial improvement is small, the benefit is great. In February 2020, researchers writing in the journal BioMed Central Musculoskeletal Disorders,(2) offered these guidelines:
“patients with Symptomatic Femoroacetabular Impingement syndrome and acetabular dysplasia (shallow hip socket) have poor sleep quality. Worsening pain from a patient’s hip pathology is associated with poor sleep, even prior to the onset of osteoarthritis of the hip. . . We also found that sleep quality was better with higher scores indicating lower pain, fewer role limitations due to emotional problems, and improved mental health. Patients presenting with hip pain from Femoroacetabular Impingement syndrome and acetabular dysplasia should be screened for sleep disturbance and may benefit from a multidisciplinary treatment approach.”
Opioids before hip arthroscopy surgery, opioids after hip arthroscopy
We are going to look at a November 2021 study from a combined research group from the University of Pittsburgh Medical Center, the Mayo Clinic, William Beaumont Hospital, Duke University, Durham and Emory University School of Medicine. This study was published in the Orthopaedic journal of sports medicine (3) . What these researchers wanted to answer was the question “what is the association of preoperative opioid use with postoperative outcomes after hip arthroscopy in patients with Femoroacetabular Impingement. Here are the findings.
- Preoperative opioid use has been shown to be a negative predictor of patient outcomes, complication rates, and resource utilization (more medical care needed) in a variety of different orthopaedic procedures.
- A total of 22,124 patients who underwent surgery between 2011 and 2018 were ultimately included in this study.
- Opioid prescriptions filled in the 6 months preceding surgery were assessed, and the average daily oral morphine equivalents (OMEs) in this period were computed for each patient. Patients were divided into 4 groups:
- patients who were opioid naïve (patients who did not use opioids at least 30 days prior to their surgery)
- patients who had more than OME per day,
- patients who had 1 to 5 OMEs per day, and
- patients who had more than 5 OMEs per day.
- Postoperative 90-day complications, health care utilization, perioperative costs, postoperative opioid use, and 1- and 3-year revision rates were then compared among groups.
Overall, the percentage of preoperative opioid-naïve patients increased from 64.5% in 2011 to 78.9% in 2018. (Signaling an increase in opioid prescriptions during these years).
- Patients who received preoperative opioids had a higher rate of complications, increased resource utilization, and increased revision rates.
- Specifically, patients taking more than 5 OMEs per day (compared with patients who preoperatively did not take opioids) had:
- increased odds of a postoperative emergency department visit
- 90-day readmission
- increased acute postoperative opioid use
- prolonged opioid use
- and 3-year revision surgery
Conclusion: “A large number of patients with FAI are prescribed opioids before undergoing hip arthroscopy, and use of these pain medications is associated with increased health care utilization, increased costs, prolonged opioid use, and early revision surgery.”
Stopping the progress of Femoroacetabular Impingement – non-surgically
Femoroacetabular Impingement and Hip Instability
There are times when femoroacetabular impingement surgery may be needed. There are other times when femoroacetabular impingement surgery may be THOUGHT to be needed. But can probably be avoided. There are times when non-surgical consideration should be given top consideration.
Here are the traditional Femoroacetabular Impingement problems that may be addressed surgically:
Pincer femoroacetabular impingement
- In pincer femoroacetabular impingement, when the hip is in full flexion (as in pulling your knee to the chest), the femoral head-neck junction hits the anterosuperior aspect (the front of the acetabulum). This problem is commonly caused by the socket being “too deep,” and the ball will pinch structures like the labrum between the acetabulum and the femur neck, this problem is also diagnosed as coxa profunda or protrusion acetabuli (where the ball of the hip protrudes into the pelvic area).
Cam femoroacetabular impingement
- In cam femoroacetabular impingement, there is abnormal contact between the head and socket of the hip because of a loss of roundness of the femoral head. Cam deformities may be recommended to surgery when there is femoral head asphericity, such as flattening of the anterior contour of the femur head/neck junction or an osseous bump. The bump is often located anterolaterally or anterosuperiorly at the head-neck junction and is commonly called a “pistol grip” deformity. This loss of roundness causes abnormal contact between the head and the socket of the hip. In cam FAI, the impingement typically occurs when the hip is flexed, but also internally rotated. As already mentioned, patients often have “mixed” FAI, meaning they have a combination of both.
“The optimal therapy for femoroacetabular impingement is unclear.” Is surgery the answer? That is UNCLEAR
Often we will hear a story from a patient where they were told that surgery is the only option. But they themselves were not convinced and started researching alternatives. For some people, surgery may be the only option. Who are those people, we are going to let the research from surgeons discussed below help answer that question?
Here is something typically that a new patient will say:
I have to have the surgery, my orthopedist is strongly recommending it. I need some bone shaved down. But to get to the surgery I have to go through a course of physical therapy. I am anxious to do the physical therapy but I am not sure how much it will help at this time. I have been doing stretching and yoga and exercises I found online. I am here and seeing a surgeon because these exercises have not really helped. (See below for our discussion on physical therapy).
This next section of our article will deal with the surgical challenges of femoroacetabular impingement. As we do in all our articles, when surgery is discussed, we bring in the opinions of some of the world’s leading surgical researchers.
In the medical journal Osteoarthritis and Cartilage (4) doctors found: “The optimal therapy for femoroacetabular impingement is unclear,” in trying to prove the surgical options available to patients. The doctors noted in their research of 18 studies comparing management strategies – none of these studies compared surgical and non-surgical treatment.
“Although evidence supports improvement in symptoms after surgery in FAI, no studies have compared surgical and non-surgical treatment. Therefore no conclusion regarding the relative efficacy of one approach over the other can be made. Surgery improves alpha angle (improper position of the ball in the socket) but whether this alters the risk of development or progression of hip osteoarthritis is unknown. This review highlights the lack of evidence for use of surgery in FAI. Given that hip geometry may be modified by non-surgical factors, clarifying the role of non-surgical approaches vs surgery for the management of FAI is warranted.”
Researchers call for FAI surgery assessment study
In the April 2018 edition of The Journal of Orthopaedic and Sports Physical Therapy, (5) researchers announced a study to assess the effectiveness of FAI surgery. Here are the highlights of what the research surgeons hope to accomplish and preliminary observations:
- The number of arthroscopic surgical procedures for patients with femoroacetabular impingement syndrome has significantly increased worldwide, but high-quality evidence of the effect of such interventions is lacking.
- The primary objective will be to determine the efficacy of hip arthroscopic procedures compared to sham surgery on patient-reported outcomes for patients with femoroacetabular impingement syndrome.
- The secondary objective will be to evaluate prognostic factors for long-term outcomes after arthroscopic surgical interventions in these patients.
- The researchers will also look at long-term outcomes in problems that are common in femoroacetabular impingement surgery post-op:
- Hip disability and Osteoarthritis
- fear of movement
- Patient expectations and disappointment
Rapid onset of hip osteoarthritis after femoroacetabular impingement surgery
In June 2019, the US Army Office of the Surgeon General out of Baylor University published these findings in the journal BMC Musculoskeletal Disorders. (6)
- One of the reported goals of hip preservation surgery is to prevent or delay the onset of osteoarthritis. This includes arthroscopic surgery to manage Femoroacetabular Impingement (FAI) Syndrome. The purpose of this study was to describe the prevalence of clinically-diagnosed hip osteoarthritis within 2 years after hip arthroscopy for FAI syndrome, and 2) determine which variables predict a clinical diagnosis of osteoarthritis after arthroscopy.
- Of 1870 participants in this group of patients (average age 32.2 years), 21.9% (409 post-surgery patients) had a postoperative clinical diagnosis of hip osteoarthritis within 2 years. The 3 significant predictors in the final model were older age, being a male, and having undergone additional hip surgery.
CONCLUSION: A clinical diagnosis of hip osteoarthritis was found in approximately 22% of young patients undergoing hip arthroscopy in as little as 2 years. . .Females were at lower risk while increasing age and multiple surgeries increased the risk for an osteoarthritis diagnosis. Osteoarthritis onset still occurs after “hip preservation” surgery in a substantial number of individuals within 2 years.
Physical therapy or surgery – some interesting studies
In the December 2018 issue of the International Journal of Sports Physical Therapy (7) research lead by Creighton University Medical Center, suggested that a well-designed and customized physical therapy program showed benefit and surgical avoidance in six patients scheduled for femoroacetabular impingement surgery. The highlights of this research are
- Despite femoroacetabular impingement being a problem of many factors, surgical management to correct bone abnormality has been the predominant focus.
- The obvious findings of bone abnormality provide a simple answer that lends itself well to the idea of surgical correction
- However, the high prevalence of bone abnormality findings in asymptomatic, pain-free individuals suggests the problem is more complex.
- The patient cases of this study illustrate the clinical reasoning process (customized therapy based on the patient’s goals and need of treatment) utilized to prioritize subjects’ treatment along with a continuum of neuromuscular control (training the muscles to help provide stability in the hip) and mobility. The treatment approach also illustrates the successful management of potential surgical candidates that elected to forego surgery after satisfactory completion of conservative management.
A brief note: We work with physical therapists, especially in patients that do not respond to physical therapy to help them respond to the treatment. Please see our article Why physical therapy and exercise did not restore muscle strength in hip osteoarthritis patients, this will show how strengthening tendons and ligaments provide the resistance necessary in some patients to maximize the benefits of the PT.
To take this line of thinking one step further, that strengthened connective tissue in the hip could provide a counterbalance in asymptomatic FAI patients, let’s look at a study (July 2018) in the Orthopaedic Journal of Sports Medicine (8) Here researchers looked at patients with femoroacetabular deformity (FAD) who do not experience pain.
- The FAD group was significantly stronger than the FAI (patients with pain) and control groups during hip extension, and the femoroacetabular deformity group had a greater sagittal (left / right) pelvic range of motion and could squat to a greater depth than the FAI group.
- The stronger hip extensors (the muscles Gluteus maximus, Biceps femoris, Semitendinosus, Semimembranosus) of the femoroacetabular deformity are associated with a greater pelvic range of motion, allowing for greater posterior pelvic tilt, possibly reducing the risk of impingement while performing the squat, and resulting in a greater squat depth compared with those with symptomatic FAI.
Conclusion: Improving hip extensor strength and pelvic mobility may positively affect symptoms for patients with FAI.
The third study could not make a recommendation as to which treatment the patient should peruse, surgery or physical therapy. Appearing in the Orthopaedic Journal of Sports Medicine (9) in April 2020, researchers at Washington University suggest “superior outcomes of surgery compared to PT. However, PT can result in improvements in some patients and does not appear to compromise surgical outcomes.”
In other words, try the physical therapy first and if it does not work, then consider surgery. Which is pretty much the standard protocol.
This too was suggested by a more recent December 2020 study in The Journal of the American Academy of Orthopaedic Surgeons, (10) here the surgeons reported:
“Controversy exists as to the management of femoroacetabular impingement. When nonsurgical management of symptomatic FAI fails, surgical management is generally indicated. However, many groups with a stake in patient care (particularly payors) have insisted on higher levels of evidence.
Recently, there have been several Level I studies (higher quality research) published, comparing physical therapy with hip arthroscopy in the management of symptomatic FAI. All of these studies have used outcomes tools developed and validated for patients with non-arthritic hip pain. Highest level evidence confirms that although patients with FAI do benefit from physical therapy, patients who undergo surgical management for FAI with hip arthroscopy benefit more than those who undergo physical therapy.”
A young female athlete helped demonstrate successful management of symptomatic bilateral femoroacetabular impingement syndrome
In September 2018, an interesting case history was presented in the Open Access Journal of Sports Medicine. (11) In this study, a young female athlete helped demonstrate successful management of symptomatic bilateral femoroacetabular impingement syndrome. She had surgery on one side and non-surgical treatment on the other side. What did the researchers find? They could not really tell.
- “The strengths of the presented case report are the opportunity to compare surgical treatment and non-surgical treatment in the same patient, as well as a long follow-up period for the surgically treated hip and the use of PROM (patient-reported outcome questioning) validated for use in a young and active population.
- The limitations in the present case report are the lack of pre-treatment PROM data for both hips, which limits the opportunity to draw any firm conclusions about the baseline condition and amount of improvement.
- The different alpha angles ( a way to measure hip dysplasia, the abnormal placement of the ball in relationship to socket) for the two hips, 60° for the surgically treated side and 50° for the non-surgically treated side, also limit the opportunity for comparison. NOTE the non-surgically treated hip dysplasia is more severe.
- No gait analysis was performed and it is, therefore, possible that the patient was unloading one hip, generating a false favorable result for the other hip.
- It is worth mentioning that both treatment regimens included physiotherapy, but postoperative physiotherapy was mainly aimed at gradually increasing the load on the hip, while physiotherapy for the non-surgically treated hip was aimed at strengthening and stabilizing the hip girdle in a pain-free range of motion.
- Peri-operatively, there were no macroscopic findings of injury to the cartilage or the labrum. With pain from the hip, this is, however, unlikely to be true and highlights the difficulty involved in assessing less extensive soft-tissue damage visually.”
The bottom line factor here is that it was, in fact, difficult to compare surgery to physical therapy even in the same person for numerous reasons. One is, the similar lack of success of the treatments was influenced by the fact the female athlete reduced her activity level. Lastly, the patient was a 31-year-old physiotherapist.
Is it Femoroacetabular impingement causing your issues or is it something else?
In the research above we noted:
- “Despite femoroacetabular impingement being a problem of many factors, surgical management to correct bone abnormality has been the predominating focus…”
- People with femoroacetabular impingement can have no symptoms at all.
So what could be the underlying cause of your hip pain?
Joint Hypermobility and Hypermobile Elhers-Danlos Syndrome
An August 2022 paper in the medical journal Arthroscopy (31) examined a greater incidence of iliopsoas tendinitis in postoperative hip arthroscopy patients treated for femoroacetabular impingement (FAI). In this study, forty patients in whom postoperative iliopsoas tendinitis developed were identified and matched to 40 control patients in whom postoperative tendinitis did not develop. Increased joint hypermobility, quantified by the Beighton (joint hypermobility) score, was associated with an increased risk of iliopsoas tendinitis.
Femoroacetabular impingement syndrome may frequently have co-existing sacroiliac joint pain
An August 2022 paper from Rush University Medical Center, published in The American journal of sports medicine (29) examined the effect of sacroiliac joint pain on surgery outcomes in patients who had hip arthroscopy for Femoroacetabular Impingement Syndrome.
The researchers noted: “Patients with femoroacetabular impingement syndrome may frequently have co-existing sacroiliac joint pain. It is known that patients with lower back pain undergoing total hip arthroplasty (total hip replacement) have inferior outcomes; however, it is unclear what the effect of sacroiliac joint pain is on outcomes after hip arthroscopy.
Study learning points:
- Patients with a minimum 2-year follow-up who underwent primary hip arthroscopy for Femoroacetabular Impingement Syndrome with sacroiliac joint pain, a total of 73 patients (75 hips) with SIJ pain were matched to 150 control patients (150 hips) without SIJ pain.
- Both groups demonstrated statistically significant improvement in all patient reported outcomes at 2 years.
- Patients with SIJ pain had significantly lower postoperative patient reported outcomes scores for pain, disability and quality-of-life.
- The SIJ pain group had significantly lower achievement of Minimal clinically important differences (MCID).
Conclusion: “Patients with Femoroacetabular Impingement Syndrome and sacroiliac joint pain on history or physical examination experience significant improvement in patient reported outcomes at 2 years after hip arthroscopy. However, they may be less likely to achieve the Minimal clinically important differences (MCID) or PASS (Patient Acceptable Symptom State – what they consider a successful treatment despite remaining symptoms) and have significantly lower postoperative patient reported outcomes compared with a matched cohort of patients without SIJ pain. Overall rates of revision and conversion to total hip replacement were similarly low in both groups.”
Is your MRI showing you what is causing your problems?
If you have a scan or MRI of your hip showing femoroacetabular impingement, doctors are saying it may as well be worthless. That is a powerful statement, here is some powerful research
- A 2017 study in the Journal of Orthopaedic Science (12) suggests “Radiographic signs of FAI were not associated with the degree of hip pain or a positive positive anterior impingement sign (the doctor’s attempt to recreate your hip pain in an examination), which suggests that radiographic findings may not be important in the clinical diagnosis of FAI.”
- In a study in the journal Clinical Orthopaedics and Related Research (13) Japanese doctors followed up with their findings that because FAI is seen on MRI in many symptom-free patients, doctors should question the need for femoroacetabular impingement surgery to correct a problem that does not seem to plague the patient.
- In a March 2018 study in the journal Hip Pelvis, researchers found that 31% of MRIs showed FAI in asymptomatic patients. (14)
Having an MRI that shows femoroacetabular impingement does not mean that is the cause of your hip problems
Is it Femoroacetabular impingement causing your issues or do you have hip tendinopathy and Greater trochanteric pain syndrome?
As we have mentioned many times in our hip pain-related articles, the hip is a big joint, we believe to help patients achieve their treatment goals, the entire hip needs to be examined with recommendations for treating the whole hip joint. We discuss this further in our article: The evidence for Prolotherapy as a hip-preserving alternative to arthroscopy and hip replacement.
- Recently in our article on greater trochanter pain syndrome, an example of the problems in getting successful treatment is found in treatment failures were concentrating on specific hip problems instead of treating the whole hip joint shows why some hip procedures did not work as well as they should have.
The example we cited is a new paper from doctors in Italy who looked to see what caused greater trochanter pain syndrome in patients with suspected femoroacetabular impingement syndrome.
- After magnetic resonance arthrography of the hip and evaluation of 189 patients, in the end, it was hard to say why patients with suspected femoroacetabular impingement syndrome also suffered from greater trochanter pain syndrome.
- Why? Because the biggest problem 38% of the patients had tendinopathy of the hip, 16% had bursitis. Problems considered “normal hip pathology.” So there were many problems causing the patient’s discomfort, simply treating one problem or the other was not going to help patients in the long run.
Is it Femoroacetabular impingement causing your issues or is it pelvic or lower back issues?
Doctors from Cambridge University Hospitals wrote in the journal International Orthopaedics (15) that extra-articular hip impingement syndromes encompass a group of conditions that have previously been an unrecognized source of pain. Extra-articular hip impingement syndromes mean problems caused from outside of the hip joint itself as opposed to intra-articular hip impingement syndromes which come from within the hip itself. Where it was once thought that hip impingement was caused by bone abnormalities limited to the ball and socket portion of the hip joint, doctors, including the Cambridge report cited below are finding that hip impingement can be caused by the pelvic bones as well.
The Cambridge doctors categorized these syndromes as:
- Ischiofemoral impingement: quadratus femoris muscle becomes compressed between the lesser trochanter portion of the thigh bone and the ischial tuberosity (the sit bones of the lower pelvis). We cover this problem in our article: Ischial tuberosity pain and ischiofemoral impingement: Here we describe Ischial tuberosity pain and ischiofemoral impingement. The focus will be on two types of problems. Impingement caused by instability and non or malunion of the fragment of the Ischial tuberosity caused by apophyseal (growth plate) avulsion fractures in young athletes.
- Subspine impingement: anatomical problems of the anterior inferior iliac spine (the wing of the upper iliac/pelvic bones) and the distal anterior femoral neck (the neck of the thigh bone) causing soft tissue entrapment of muscle and tendon.
- Iliopsoas impingement: friction between the iliopsoas muscle and the hip labrum, resulting in hip labrum breakdown. We cover issues in this article of the iliopsoas or psoas muscle as a cause of difficult-to-treat groin pain. Also, see our article on surgery for hip labral tear.
- Deep gluteal syndrome: pain occurs in the buttock due to the entrapment of the sciatic nerve in the deep gluteal space. In our articles, we cover a lot of information on buttock pain and the pelvis, lower spine connection. See also the connection with hamstring injuries.
- Pectineofoveal impingement: pain occurs when the medial synovial fold impinges against overlying soft tissue, primarily the zona orbicularis (the hip annular ligament).
The researchers concluded with a message to doctors that extra-articular hip impingement syndromes should be taken into consideration and should form a part of the differential diagnoses alongside intra-articular pathology including femoro-acetabular impingement particularly in the younger patient with a non-arthritic hip.
Questioning the MRI AGAIN
As described above, Subspine impingement involves problems of the anterior inferior iliac spine and the neck of the thigh bone. In looking at patients with Anterior Inferior Iliac Spine problems, doctors at the Walter Reed National Military Medical Center suggest that a high percentage of patients with Anterior Inferior Iliac Spine problems are associated with subspinous impingement are, in fact, asymptomatic. That the current radiographic classification system should not be used exclusively for clinical decision-making. (16)
The conclusion of this research made a point about function. If you have back pain, it may not be related to your hip problems. If you have back pain with functional disability it does cause hip problems
A January 2022 study from researchers at The Ohio State University Wexner Medical Center (30) examined the prevalence of low back pain and related disability in patients with femoroacetabular impingement syndrome. As stated in the paper, it is understood that low back pain has been associated with worse hip function for persons with femoroacetabular impingement syndrome (FAIS). What the researchers wanted to establish here was a patient profile to help doctors recognize problems of hip function and both low back related disability and low back pain severity. The authors hypothesized that participants with low back pain would be older, have higher body mass index (BMI), and report worse groin pain, longer symptom duration, and worse hip function.
Using Visual analog pain scales (VAS 0-100) the researchers were able to categorize participants with and without clinically significant low back pain. Age, sex, BMI, pain severity and duration, and hip function (33-item Hip Outcome Tool [iHOT33]) were compared between those with and without clinically significant LBP. Correlations were evaluated between the modified Oswestry Disability Index (the most common test to assess a patient’s answers for low back pain) and iHOT33, ODI and groin pain severity, LBP severity and iHOT33, and LBP and groin pain severity.
Sixty percent of participants reported clinically significant low back pain.
- These participants reported worse iHOT33 scores (a iHOT33 survey is usually given to younger patients to help assess a recommendation to hip arthroscopic surgery – a worse score means hip pain and disability) than those without clinically significant low back pain.
- Worse Oswestry Disability Index (the most common test to assess a patient’s answers for low back pain) scores were associated with worse iHOT33 scores. (The worse the back pain the worse the hip pain).
- Clinically significant low back pain is highly prevalent in persons with femoroacetabular impingement syndrome and is associated with worse hip function.
The conclusion of this research made a point about function. If you have back pain, it may not be related to your hip problems. If you have back pain with functional disability it does cause hip problems.
- Worse low back pain-related disability, but not low back pain severity, was strongly associated with worse hip function. (In other words low back pain did not cause a worse hip condition, but low back pain with functional disability did).
The problem of pelvic tilt in Femoroacetabular impingement
A February 2021 study in the European Spine Journal (17) looked at adult spinal deformity patients’ hip orientation in a standing position and how they anatomically compensated for problems of pelvic tilt, abnormal spine curvature, and leg-length discrepancies. What they were keying in on was how much a patient bent their knees to try to “level” out.
The patients were divided into two groups:
- Adult spinal deformity with knee flexion if they compensated by flexing their knees
- and ASD with knee extension (simply, straightening out of the knee).
The patients with Adult spinal deformity who used a bent knee approach to trying to level out had:
- the higher sagittal vertical axis (a spinal imbalance leading to loss of the natural curvature of the spine),
- Pelvic tilt with an addition altered tilting of the acetabular (hip socket).
- pelvic incidence-lumbar lordosis mismatch
Conclusions: Adult spinal deformity patients compensating with knee flexion have altered hip orientation which can lead to posterior femoroacetabular impingement, thus limiting pelvic retroversion (the natural movement of the pelvis behind the spine in part due to loss of the natural curve or lordosis of the lumbar region). This underlying mechanism could be potentially involved in the hip-spine syndrome.
Please see our article: Treatments for leg length discrepancy, pelvic tilt, pelvic incidence-lumbar lordosis mismatch, and walking difficulties for a more detailed discussion.
Doctors are noting that one of the main causes of Femoroacetabular impingement is hip arthroscopic surgery.
New research on Femoroacetabular impingement surgery is concerning. Doctors are noting that one of the main causes of Femoroacetabular impingement is hip arthroscopic surgery.
In an editorial, James H. Lubowitz, M.D. (Editor-in-Chief) wrote in the medical journal Arthroscopy:
Hip femoroacetabular impingement is overwhelmingly the primary cause of revision surgery after hip arthroscopy. FAI imaging is confusing and requires additional research. Therefore, hip arthroscopic surgeons must become experts at clinical evaluation and examination. (18)
Clearly, a connection to the MRI research mentioned earlier.
- Further, researchers say that patients with protrusion acetabuli (displacement between the ball and socket, seen in advancing osteoarthritis and more common in middle-aged women) are at increased risk for failure after Femoroacetabular Impingement Surgery. (19)
In an editorial, Dr. JW Thomas Byrd writing in Arthroscopy: The Journal of Arthroscopic & Related Surgery, suggests:
When performing arthroscopic surgical management of symptomatic cases of hip femoroacetabular impingement, it is important to consider how much cam lesion resection (removal of labral, cartilage, and/or bone) is required, if any. Generally, failure to adequately address a cam lesion could result in progressive damage to the articular cartilage. Thus, while it is important to consider exactly how much arthroscopic intervention is necessary to achieve successful results, the potential consequences of neglecting a cam lesion are at least as worrisome as the risks of indicated cam lesion treatment. (20)
Capsular plication – persistent hip pain after hip arthroscopy – the need for another arthroscopic surgery
Briefly, capsular plication is when loose tissue is folded up in the hip capsule to try to alleviate the problems of that loose tissue getting caught and impinged again. We are going to bring in the surgeons to explain this:
In the journal Arthroscopy Techniques, surgeons wrote:(21)
“The most commonly reported reasons for persistent hip pain after hip arthroscopy are residual femoroacetabular impingement, dysplasia, and dysplasia variants, or extra-articular impingement. (The outside of the hip joint such as Ischial tuberosity pain syndrome or Greater trochanteric pain syndrome.)
Capsular defects after hip arthroscopy may suggest an alteration of the biomechanical properties of the iliofemoral ligament and lead to iatrogenically (the surgery caused) induced hip instability. There are a growing number of biomechanical and clinical studies showing the importance of capsular management during hip arthroscopy.”
Compromised hip cartilage after surgery
In June 2017, researchers in Denmark, as part of the Danish Hip Arthroscopy Registry study and publishing in the medical journal of the International Society of Orthopaedic Surgery and Traumatology (22) questioned how cartilage degeneration is treated in patients undergoing Femoroacetabular Impingement surgery.
Listen to these results:
- The majority of patients with femoroacetabular impingement undergoing hip arthroscopy have significant cartilage changes at the time of surgery primarily at the acetabulum and to a lesser degree at the femoral head.
- During femoroacetabular impingement surgery, the majority of patients have cartilage debridement performed but rarely cartilage repair.
- The presence of severe cartilage injury at the time of arthroscopic femoroacetabular impingement surgery results in a reduced subjective outcome and hip function.
In March of 2018, New York University’s Bulletin of the Hospital for Joint Diseases published Beyond the Scope Open Treatment of Femoroacetabular Impingement. (23)
In this paper, researchers suggested:
- Several recent reports of revision hip arthroscopy for treatment of residual FAI have exposed potential shortcomings of arthroscopic treatment of FAI, specific limitations with hip arthroscopy’s ability to address large or complex cam and pincer deformities.
- While hip arthroscopy can certainly be useful for the treatment of FAI in some patients, we have yet to identify which patients truly benefit from this minimally invasive approach and those who are better served by open surgical techniques.
Kinesiophobia and Pain Catastrophizing in Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome
Kinesiophobia is fear of movement, pain catastrophizing is fear of pain. You may think that these fears would be characteristic of people before surgery. Indeed they are. But they are also characteristic of people after surgery. An April 2020 study (24) from researchers at the Departments of Orthopedic Surgery, Rush University Medical Center, and Wake Forest Baptist Health, found:
“Patient kinesiophobia and pain catastrophizing both shows significant improvements 1 year after undergoing hip arthroscopy for Femoroacetabular Impingement Syndrome. However, pain catastrophizing scores at 1 year are significantly greater in patients not achieving a minimal clinically important difference (outcome after surgery to before surgery. The surgery was not successful in the minds of the patient). The minimal clinically important difference, whereas no association, was identified between kinesiophobia and likelihood for Minimal clinically important difference achievement (successful surgery).”
Sports hernia and femoroacetabular impingement in athletes
The idea that sports-related chronic groin pain represents a major diagnostic and therapeutic challenge in sports medicine has been discussed at length in medical research. Ohio State University researchers writing in the medical journal Frontiers in Surgery. write the “complexity of the anatomy and biomechanics of the groin makes these injuries more difficult to identify and manage. Patients may find themselves evaluated by multiple physicians and receive numerous diagnostic studies over a period of months. (25)
Italian researchers reporting in the World Journal of Clinical Cases say Femoroacetabular impingement has been reported in as few as 12% to as high as 94% of patients with sports hernias, athletic pubalgia, or adductor-related groin pain.
Cam-type impingement is proposed to lead to increased symphyseal motion (resulting in cartilage deterioration) with overload on the surrounding extra-articular structures and muscle, which can result in the development of sports hernia and athletic pubalgia. In simpler terms, hip/pelvic instability.
In this paper, the researchers are suggesting that for patients with FAI and sports hernia, the surgical management of both problems is more effective than sports pubalgia surgery or hip arthroscopy alone (89% vs 33% of cases).
As sports hernias and FAI are typically treated by general and orthopedic surgeons, respectively, a multidisciplinary approach for diagnosis and treatment is recommended for optimal treatment of patients with these injuries. (26)
This idea that to successfully treat a sports hernia you would need to surgically repair numerous areas is not new. In 2011 doctors at the Minnesota Orthopedic Sports Medicine Institute wrote: When surgery only addressed either the athletic pubalgia or intra-articular hip pathology in this patient population, outcomes were suboptimal. Surgical management of both disorders concurrently or in a staged manner led to improved postoperative outcomes scoring and an unrestricted return to sporting activity in 89% of hips. (27)
For some athletes, this is good news, for others multi-stage surgeries present time off challenges. Here are the results of that study:
- 37 hips (mean patient age, 25 years) were diagnosed with both symptomatic athletic pubalgia and symptomatic intra-articular hip joint pathology.
- There were 8 professional athletes, 15 collegiate athletes, 5 elite high school athletes, and 9 competitive club athletes.
- Outcomes included an evaluation regarding return to sports and various scoring systems to determine successful treatment.
- Thirty-one hips underwent thirty-five athletic pubalgia surgeries.
- Hip arthroscopy was performed in 32 hips (30 cases of femoroacetabular impingement treatment, 1 traumatic labral tear, and 1 borderline dysplasia).
- Of 16 hips that had athletic pubalgia surgery as the index procedure, 4 (25%) returned to sports without limitations, and 11 (69%) subsequently had hip arthroscopy at a mean of 20 months after pubalgia surgery.
- Of 8 hips managed initially with hip arthroscopy alone, 4 (50%) returned to sports without limitations, and 3 (43%) had subsequent pubalgia surgery at a mean of 6 months after hip arthroscopy.
- Thirteen hips had athletic pubalgia surgery and hip arthroscopy in one setting. Concurrent or eventual surgical treatment of both disorders led to improved postoperative outcomes scores sporting activity in 89% of hips (24 of 27).
Ligaments, tendons, hip instability, and microinstability
Femoroacetabular impingement is more than treating part of the hip
In the medical journal Arthroscopy (28), doctors at the University of Rochester looked to see if femoroacetabular impingement is associated with hip instability and in what way. One thing they found was that patients suffered from frank dislocations and posterior subluxation events, the patients’ hips were frequently popping out of place.
What does this mean? It means that hip instability proceeded the need for the bone spurs. The hip was unstable.
In the above research, we discussed a tightening or strengthening of the hips and tendons of the hip to make physical therapy more effective in femoroacetabular impingement treatments. Ligaments and tendons are among the soft connective tissue that holds joints in their anatomically correct shape and helps the muscles and bones provide locomotion and range of motion. Ligaments hold bones to bones and tendons hold muscle to the bones.
For physical therapy to work, you need as much resistance as can be generated. Strength training is resistance training. Now, what if you do not have good resistance? For one thing, physical therapy will be less rewarding. For another, you will also have hip hypermobility, or more commonly called “instability of the hip.”
What we have documented through this research is that to treat femoroacetabular impingement you need to treat the whole hip with the goal of regenerating soft tissue to add strength and stability to the joint. Enter Prolotherapy.
PRP Prolotherapy for Femoroacetabular Impingement
Prolotherapy is the injection of simple sugar, dextrose. The idea is that dextrose injections will cause a controlled inflammatory response that will focus on strengthening and rebuilding the damaged soft tissue holding the hip in place. Strengthened soft tissue, i.e, ligaments, will stabilize the hip joint and help pull things back into place and reduce destructive joint forces in the hip.
PRP is Platelet Rich Plasma Therapy. PRP treatment re-introduces your own concentrated blood platelets into the hip area. Your blood platelets contain growth and healing factors. When concentrated through simple centrifuging, your blood plasma becomes “rich” in healing factors, thus the name Platelet RICH plasma.
- Prolotherapy and PRP treatments would be at the early onset of the problem with an unstable hip.
- The treatment entails doing injections in the hip and around the socket. This will help stabilize the hypermobility of the bone against the socket. PRP or stem cell therapy may be included in the tissue deep within the hip that is “shredded” or significantly damaged.
- What is the recovery time in utilizing these treatments? That depends on how long you have had symptoms. The plus side of these injections, as opposed to FAI surgery, is that the downtime is significantly less in successful cases. FAI surgery typically would require 6 months of physical therapy afterward.
- With our treatments, we would consider in severe cases 6 treatments at 6-week intervals. All the while, the patient would be able to train or return to work.
PRP injections at the time of surgery
Some of the orthopedic surgeons are trying to improve their results and are utilizing PRP at the time of surgery. The thought process for this is that because capsulotomies are required for hip arthroscopy, often involving cutting through the iliofemoral ligament (the strongest ligament in the body), arthroscopy then causes an injury to the hip capsule and iliofemoral ligament, leading to iatrogenically (surgical injury) induced hip instability. Thus, the surgeons think that putting PRP into the joint could help healing.
A study published in Arthroscopy (x) released its findings after evaluating the clinical and immunologic effects of intra-articular platelet-rich plasma (PRP) in patients who underwent arthroscopic hip surgery for FAI. The patients receiving the surgery were divided into two groups: those that received an intra-articular injection of PRP and those that did not. All patients were evaluated at three, six, and 24 months after surgery. The surgeons found that patients who had received PRP had lower post-operative pain scores. It should be noted that the PRP injection was performed intra-articularly, not directly to the capsule or iliofemoral ligament. Again, the surgeon believes the problem is inside the joint so that is where they are injecting the PRP. The cause of hip pain and the x-ray and MRI findings of FAI are outside the joint.
This is a hip procedure on a runner who has hip instability and a lot of clicking and popping in the front of the hip.
In this video Prolotherapy treatments are demonstrated by Ross Hauser, MD:
- This is a hip procedure on a runner who has hip instability and a lot of clicking and popping in the front of the hip.
- This patient has a suspected labral tear and ligament injury.
- The injections are treating the anterior part of the hip which includes the hip labrum and the Greater Trochanter area, the interior portion, the gluteus minimus is treated.
- The Greater Trochanter area is where various attachments of the ligaments and muscle tendons converge, including the gluteus medius.
- From the front of the hip (1:05), we can treat the pubofemoral ligament and the iliofemoral ligaments.
- From the posterior approach, I’m going to inject some proliferant within the hip joint itself, and then, of course, we’re going to do all the attachments in the posterior part of the hip and that will include the ischiofemoral ligament, the iliofemoral ligaments. We can also get the attachments of the smaller muscles you’re obviously going to get you to know some of the smaller muscles too including the Obturator, the Piriformis attachments onto the Greater Trochanter
- Hip problems are ubiquitous, the hip ligament injury or hip instability is a cause of degenerative hip disease and it’s the reason why people have to get to get hip replacements.
When Prolotherapy is considered
In the video above you will see a comprehensive Prolotherapy injection treatment for a runner with hip issues. Simply Prolotherapy is the injection of simple dextrose (sugar) into the joint to create a positive inflammatory healing response which will bring the body’s natural growth factors to the area. The simple goal of this simple treatment is to regenerate ligaments, tendons, and cartilage.
In our numerous research papers on the problems of the hip and treatment with Prolotherapy, we suggested better results in patients with some reasonable range of motion remaining, ie 50% or greater normal range of motion, then Prolotherapy works at helping with the pain and exercises like cycling and swimming will slowly allow the patient to regain some of the lost range of motion.
- Some patients have conditions that predispose them to less range of motion. A person may present with 50% of normal motion in his right hip with regard to external rotation compared to his left hip, but not have any pain in the right hip. He may be able to run and continue sports with no problem, as the range of motion deficiency does not necessarily hinder sports performance or feel painful.
- In another example, a patient has FAI and his main symptom is groin pain. The patient is a cyclist and is experiencing pain with cycling. In seeing this particular patient, we would try and determine if he truly has FAI on physical examination, looking for a positive impingement sign, and then determine the cause of it. If the cause is some tremendous structural problem with the hip like a dysmorphic problem or orientation problem of the femur, then surgical correction may be needed. However the most common cause of FAI and other premature osteoarthritic conditions is simply some type of soft tissue injury such as a ligament injury, so Prolotherapy would be realistically thought of as a better option.
- Sometimes the patient will only achieve pain relief, which, of course, the patient is excited about. However, some sports like martial arts require not only improved pain levels but also improved range of motion. So sometimes, even though the patient is a good Prolotherapy candidate for decreasing pain levels, the patient may still need arthroscopy or some other surgical procedure to help with range of motion. It is surprising, however, the high number of patients we have seen over the years who do not really get a much-improved range of motion with surgical procedures and have supported these observations within the research above.
Questions about our treatments?
If you have questions about Femoroacetabular Impingement and how we may be able to help you, please contact us and get help and information from our Caring Medical staff.
1 Savic M, D’Angelo K. Exploring the role of microinstability of the hip: an atypical presentation of femoroacetabular impingement (FAI) and labral tear in a collegiate endurance athlete: a case report. The Journal of the Canadian Chiropractic Association. 2019 Dec;63(3):187. [Google Scholar]
2 Reddy N, Martinez JR, Mulligan E, Nakonezny P, Wells J. Sleep quality and nocturnal pain in patients with femoroacetabular impingement and acetabular dysplasia. BMC Musculoskelet Disord. 2020 Feb 28;21(1):134. doi: 10.1186/s12891-020-3151-6. [Google Scholar]
3 Fairley J, Wang Y, Teichtahl AJ, Seneviwickrama M, Wluka AE, Brady SR, Hussain SM, Liew S, Cicuttini FM. Management options for femoroacetabular impingement: a systematic review of symptom and structural outcomes. Osteoarthritis Cartilage. 2016 Apr 20. pii: S1063-4584(16)30048-6. [Google Scholar]
4 Nazzal EM, Wilson JM, Farley KX, Schwartz AM, Xerogeanes JW. Association of Preoperative Opioid Use With Complication Rates and Resource Use in Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement. Orthopaedic journal of sports medicine. 2021 Nov 19;9(11):23259671211045954.
5 Risberg MA, Ageberg E, Nilstad A, Lund B, Nordsletten L, Løken S, Ludvigsen T, Kierkegaard S, Carsen S, Kostogiannis I, Crossley KM. Arthroscopic surgical procedures versus sham surgery for patients with femoroacetabular impingement and/or labral tears: study protocol for a randomized controlled trial (HIPARTI) and a prospective cohort study (HARP). journal of orthopaedic & sports physical therapy. 2018 Apr;48(4):325-35. [Google Scholar]
6 Rhon DI, Greenlee TA, Sissel CD, Reiman MP. The two-year incidence of hip osteoarthritis after arthroscopic hip surgery for femoroacetabular impingement syndrome. BMC musculoskeletal disorders. 2019 Dec;20(1):266. [Google Scholar]
7 Narveson JR, Haberl MD, Vannatta CN, Rhon DI. CONSERVATIVE TREATMENT CONTINUUM FOR MANAGING FEMOROACETABULAR IMPINGEMENT SYNDROME AND ACETABULAR LABRAL TEARS IN SURGICAL CANDIDATES: A CASE SERIES. International journal of sports physical therapy. 2018 Dec;13(6):1032. [Google Scholar]
8 Catelli DS, Kowalski E, Beaulé PE, Smit K, Lamontagne M. Asymptomatic Participants With a Femoroacetabular Deformity Demonstrate Stronger Hip Extensors and Greater Pelvis Mobility During the Deep Squat Task. Orthopaedic journal of sports medicine. 2018 Jul 17;6(7):2325967118782484. [Google Scholar]
9 Schwabe M, Cheng AL, Pascual-Garrido C, Harris-Hayes M, Harris M, Hunt D, Prather H, Clohisy JC, Nepple JJ. HIP ARTHROSCOPY VS. PHYSICAL THERAPY IN PATIENTS WITH FEMOROACETABULAR IMPINGEMENT: A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS. Orthop J Sports Med. 2020 Apr 30;8(4 suppl3):2325967120S00211. doi: 10.1177/2325967120S00211. PMCID: PMC7222232. [Google Scholar]
10 Gao I, Safran MR. Nonsurgical Versus Surgical Management of Femoroacetabular Impingement: What Does the Current Best Evidence Tell Us. JAAOS-Journal of the American Academy of Orthopaedic Surgeons. 2020 Dec 21:10-5435. [Google Scholar]
11 Öhlin A, Ayeni OR, Swärd L, Karlsson J, Sansone M. Bilateral femoroacetabular impingement syndrome managed with different approaches: a case report. Open access journal of sports medicine. 2018;9:215. [Google Scholar]
12 Yamauchi R, Inoue R, Chiba D, Yamamoto Y, Harada Y, Takahashi I, Nakaji S, Ishibashi Y. Association of clinical and radiographic signs of femoroacetabular impingement in the general population. J Orthop Sci. 2016 Nov 4. [Google Scholar]
13 Ahn T, Kim CH, Kim TH, Chang JS, Jeong MY, Aditya K, Yoon PW. What is the Prevalence of Radiographic Hip Findings Associated With Femoroacetabular Impingement in Asymptomatic Asian Volunteers? Clin Orthop Relat Res. 2016 Dec;474(12):2655-2661. [Google Scholar]
14 Han J, Won SH, Kim JT, Hahn MH, Won YY. Prevalence of Cam Deformity with Associated Femoroacetabular Impingement Syndrome in Hip Joint Computed Tomography of Asymptomatic Adults. Hip & pelvis. 2018 Mar 1;30(1):5-11. [Google Scholar]
15 Nakano N, Yip G, Khanduja V. Current concepts in the diagnosis and management of extra-articular hip impingement syndromes. Int Orthop. 2017 Apr 11. doi: 10.1007/s00264-017-3431-4. [Google Scholar]
16 Balazs GC, Williams BC, Knaus CM, Brooks DI, Dickens JF, McCabe MP, Anderson TD. Morphological Distribution of the Anterior Inferior Iliac Spine in Patients With and Without Hip Impingement: Reliability, Validity, and Relationship to the Intraoperative Assessment. Am J Sports Med. 2017 Apr;45(5):1117-1123. [Google Scholar]
17 Mekhael M, Kawkabani G, Saliby RM, Skalli W, Saad E, Jaber E, Rachkidi R, Kharrat K, Kreichati G, Ghanem I, Lafage V. Toward understanding the underlying mechanisms of pelvic tilt reserve in adult spinal deformity: the role of the 3D hip orientation. European Spine Journal. 2021 Feb 27:1-9. [Google Scholar]
18 Lubowitz JH. Editorial Commentary: Hip Femoroacetabular Impingement Surgery Requires Improved Radiologic Research and Expert Understanding of Hip Clinical Examination. Arthroscopy. 2015 Jul;31(7):1391. [Google Scholar]
19 Hanke MS, Steppacher SD, Zurmühle CA, Siebenrock KA, Tannast M. Hips with protrusio acetabuli are at increased risk for failure after femoroacetabular impingement surgery: A 10-year followup. Clinical Orthopaedics and Related Research. 2016 Oct 1;474(10):2168-80. [Google Scholar]
20 Byrd JW. Editorial Commentary: Hip Femoroacetabular Impingement Correction: Risk Versus Reward, or How Much Is Too Much? Arthroscopy. 2017 Apr;33(4):780-782. [Google Scholar]
21 Levy DM, Grzybowski J, Salata MJ, Mather RC 3rd, Aoki SK, Nho SJ. Capsular Plication for Treatment of Iatrogenic Hip Instability. Arthrosc Tech. 2015 Nov 2;4(6):e625-30. doi: 10.1016/j.eats.2015.07.007. [Google Scholar]
22 Lund B, Nielsen TG, Lind M. Cartilage status in FAI patients–results from the Danish Hip Arthroscopy Registry (DHAR). SICOT-J. 2017;3. [Google Scholar]
23 Clapp IM, Nwachukwu BU, Beck EC, Rasio JP, Alter T, Allison B, Nho SJ. What is the Role of Kinesiophobia and Pain Catastrophizing in Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome? Arthrosc Sports Med Rehabil. 2020 Jan 8;2(2):e97-e104. doi: 10.1016/j.asmr.2019.12.001. [Google Scholar]
24 Ryan MK, Youm T, Vigdorchik JM. Beyond the Scope. Bulletin of the Hospital for Joint Diseases. 2018;76(1):47-54. [Google Scholar]
25 Strosberg DS, Ellis TJ, Renton DB. The Role of Femoroacetabular Impingement in Core Muscle Injury/Athletic Pubalgia: Diagnosis and Management. Frontiers in Surgery. 2016;3:6.[Google Scholar]
26 Munegato D, Bigoni M, Gridavilla G, Olmi S, Cesana G, Zatti G. Sports hernia and femoroacetabular impingement in athletes: A systematic review. World Journal of Clinical Cases : WJCC. 2015;3(9):823-830. [Google Scholar]
27 Larson CM, Pierce BR, Giveans MR. Treatment of athletes with symptomatic intra-articular hip pathology and athletic pubalgia/sports hernia: a case series. Arthroscopy. 2011 Jun;27(6):768-75. [Google Scholar]
28 Canham CD, Yen YM, Giordano BD. Does Femoroacetabular Impingement Cause Hip Instability? A Systematic Review. Arthroscopy. 2015 Sep 27. pii: S0749-8063(15)00646-5. [Google Scholar]
29 Horner NS, Rice MW, Sivasundaram L, Ephron CG, Nho SJ. Effect of Sacroiliac Joint Pain on Outcomes in Patients Undergoing Hip Arthroscopy for the Treatment of Femoroacetabular Impingement Syndrome: A Matched Comparative Cohort Analysis at Minimum 2-Year Follow-up. The American journal of sports medicine.:3635465221108975. [Google Scholar]
30 Brown‐Taylor L, Bordner H, Glaws K, Vasileff WK, Walrod B, Di Stasi S. Prevalence of low back pain and related disability in patients with femoroacetabular impingement syndrome. PM&R. 2022 Jan;14(1):8-18. [Google Scholar]
31 Mojica ES, Rynecki ND, Akpinar B, Haskel JD, Colasanti CA, Gipsman A, Youm TJ. Joint Hypermobility Is Associated With Increased Risk of Postoperative Iliopsoas Tendinitis After Hip Arthroscopy for Femoroacetabular Impingement. Arthroscopy: the journal of arthroscopic & related surgery: official publication of the Arthroscopy Association of North America and the International Arthroscopy Association.:S0749-8063. [Google Scholar]
32 Rafols C, Monckeberg JE, Numair J, Botello J, Rosales J. Platelet-rich plasma augmentation of arthroscopic hip surgery for femoroacetabular impingement: a prospective study with 24-month follow-up. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2015 Oct 1;31(10):1886-92. [Google Scholar]
This page was updated August 4, 2022