Diagnosis and management of femoroacetabular impingement (2024)

INTRODUCTION

Femoroacetabular impingement (FAI) is a pathological hip condition characterised by abnormal contact between the acetabulum and femoral head–neck junction.1 This can occur within the normal physiological range of motion as a result of osseous abnormalities described as either cam or pincer deformities. Cam deformities describe an abnormal anterosuperior femoral head–neck junction, whereas pincer deformities describe abnormalities in the shape or orientation of the acetabulum (Figure 1). Some patients have both deformities, designated mixed pathology.2 Impingement can also occur in a morphologically normal hip as a result of extreme range of motion activities, such as in ballet dancers or gymnasts.

Repeated abutment of the femoral neck against the acetabular rim can result in injury to the labrum and adjacent cartilage.3 Over time these focal lesions may progress to more extensive degenerative disease. There is increasing evidence implicating FAI in the development of osteoarthritis (OA).1,4 In a large population study, cam and/or pincer deformities were found in 71% of males and 37% of females with hip OA.5 Recent longitudinal studies also support this association.6

PRESENTATION

FAI commonly presents in healthy, active adults, most frequently between the ages of 25 and 50 years. In older patients it is more frequently accompanied by OA.

Deep intermittent discomfort, during or after activity is the most common presenting complaint. The first step in assessment involves a comprehensive pain history. Intermittent discomfort in the groin during or after repetitive or persistent hip flexion is characteristic of anterior impingement resulting from either cam or pincer deformities. Sprinting or kicking sports, hill climbing or prolonged sitting in low chairs are common exacerbating activities. Pain may be referred to the anterior thigh, symphysis pubis, or the ipsilateral testicl* in men.

Pincer deformities may also give rise to posterior impingement with pain experienced in the buttock or sacroiliac region and are often difficult to differentiate from pain referred from the low back or sacroiliac joint. Repeated hyperextension with such activities as fast-walking, or walking downhill are common exacerbating activities. Posterior hip pain during intercourse is also a frequent complaint in women.

Associated mechanical symptoms such as catching or clicking may be seen when labral tears are also present. Duration of symptoms is variable, and patients sometimes report an inciting event.

EXAMINATION

Antalgic or Trendelenberg-gait patterns may be observed.

Internal rotation with the hip at 90° of flexion is typically markedly limited. Flexion and abduction are also often limited, although this is a less consistent feature.

The hip impingement test is performed with the patient supine with hip and knee flexed to 90°, the hip is progressively rotated from external rotation to internal rotation while moving from abduction to adduction (Figure 2). A positive test elicits a sudden, sharp pain in the hip. Patients often report that the manoeuvre recreates their typical symptoms. A positive impingement test has been shown to be present in more than 90% of patients who go on to have FAI confirmed either radiologically or at the time of surgery,1,7 in addition it has a high positive predictive value for labral pathology.8

INVESTIGATION

TREATMENT

CONCLUSION

FAI is a common, often unrecognised condition causing hip pain and degenerative hip disease.

Careful history and examination (a positive impingement test in particular) are key to the diagnosis and enough to alert the GP to the possibility of FAI.

Surgery has two main goals: to provide symptomatic relief and functional improvement in the short term, for which there is increasing evidence; and potentially modify the disease process and delay or even prevent the onset of OA.

GPs have an important role to play in the recognition and management of FAI.

Notes

REFERENCES

1. 1.↵
   1. Ganz R,
   2. Parvizi J,
   3. Beck M,
   4. et al.

   (2003) Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res (417):112–120.

2. 2.↵
   1. Beck M,
   2. Kalhor M,
   3. Leunig M,
   4. Ganz R

   (2005) Hip morphology influences the pattern of damage to the acetabular cartilage: femoroacetabular impingement as a cause of early osteoarthritis of the hip. J Bone Joint Surg Br 87(7):1012–1018.

   OpenUrlCrossRefPubMed

3. 3.↵
   1. Wagner S,
   2. Hofstetter W,
   3. Chiquet M,
   4. et al.

   (2003) Early osteoarthritic changes of human femoral head cartilage subsequent to femoro-acetabular impingement. Osteoarthritis Cartilage 11(7):508–518.

   OpenUrlCrossRefPubMed

4. 4.↵
   1. Ganz R,
   2. Leunig M,
   3. Leunig-Ganz K,
   4. Harris WH

   (2008) The etiology of osteoarthritis of the hip: an integrated mechanical concept. Clin Orthop Relat Res 466(2):264–272.

   OpenUrlCrossRefPubMed

5. 5.↵
   1. Gosvig KK,
   2. Jacobsen S,
   3. Sonne-Holm S,
   4. et al.

   (2010) Prevalence of malformations of the hip joint and their relationship to sex, groin pain, and risk of osteoarthritis: a population-based survey. J Bone Joint Surg Am 92(5):1162–1169.

   OpenUrlAbstract/FREE Full Text

6. 6.↵
   1. Agricola R,
   2. Heijboer MP,
   3. Bierma-Zeinstra SM,
   4. et al.

   (2013) Cam impingement causes osteoarthritis of the hip: a nationwide prospective cohort study (CHECK). Ann Rheum Dis 72(6):918–923.

   OpenUrlAbstract/FREE Full Text

7. 7.↵
   1. Martin RL,
   2. Kelly BT,
   3. Leunig M,
   4. et al.

   (2010) Reliability of clinical diagnosis in intraarticular hip diseases. Knee Surg Sports Traumatol Arthrosc 18(5):685–690.

   OpenUrlCrossRefPubMed

8. 8.↵
   1. Hananouchi T,
   2. Yasui Y,
   3. Yamamoto K,
   4. et al.

   (2012) Anterior impingement test for labral lesions has high positive predictive value. Clin Orthop Relat Res 470(12):3524–3529.

   OpenUrlCrossRefPubMed

9. 9.↵
   1. Hunt D,
   2. Prather H,
   3. Harris Hayes M,
   4. Clohisy JC

   (2012) Clinical outcomes analysis of conservative and surgical treatment of patients with clinical indications of prearthritic, intra-articular hip disorders. PM R 4(7):479–487.

   OpenUrlCrossRefPubMed

10. 10.↵
    1. Nicholls AS,
    2. Kiran A,
    3. Pollard TC,
    4. et al.

    (2011) The association between hip morphology parameters and nineteen-year risk of end-stage osteoarthritis of the hip: a nested case-control study. Arthritis Rheum 63(11):3392–3400.

    OpenUrlCrossRefPubMed

11. 11.↵
    1. Clohisy JC,
    2. St John LC,
    3. Schutz AL

    (2010) Surgical treatment of femoroacetabular impingement: a systematic review of the literature. Clin Orthop Relat Res 468(2):555–564.

    OpenUrlCrossRefPubMed

12. 12.↵
    1. Matsuda DK,
    2. Carlisle JC,
    3. Arthurs SC,
    4. et al.

    (2011) Comparative systematic review of the open dislocation, mini-open, and arthroscopic surgeries for femoroacetabular impingement. Arthroscopy 27(2):252–269.

    OpenUrlCrossRefPubMed