Hip Pointers From 1st Annual UTOSM Hip Symposium

Hip Pointers – Takeaways from the 1^st UTOSM Hip Symposium

Femoral Acetabular Impingement (FAI)

• FAIS (femoral acetabular impingement syndrome) = motion related hip disorder due to symptomatic premature contact between the acetabulum and proximal femur with triad of symptoms, clinical signs and imaging findings
• Distinguish between extra- and Intra-articular hip pathology (positional groin pain reproduced with FADIR)
• 25% of asymptomatic patients have xray evidence of FAI
• Concept of ‘hips at risk’ = abnormal anatomy, abnormal loads or both
• CAM type (Green in figure 1)
  • Most are in anterosuperior position
  • Xray – ask for standing AP pelvis, 45 degree Dunn view, and possibly also frog leg lateral to identify CAM morphology and look for secondary signs of impingement (os acetabuli, acetabular rim fractures, synovial herniation pits)
  • Alpha angle > 55 degrees is abnormal and > 70 degrees associated with focal cartilage defects and predisposition to OA
• Pincer type (Red in figure 1)
  • Imaging findings = coxa profunda, protrusion acetabuli, cross-over sign

Figure 1 AP pelvis with findings of FAI:

• Physiotherapy is first line treatment for symptomatic FAI and should be active, core-based protocols with supervision
• Without treatment, FAI symptoms worsen over time, but the long term outcome of those with FAI is still unknown
• Does FAI cause OA?
  • CAM type with elevated alpha angles > 70 predispose to OA, less evidence for pincer impingement
  • No evidence having a labral tear predisposes to OA
  • No evidence that surgery for CAM deformity stops OA development. Operative intervention is for symptomatic patients only

Labral tears

Figure 2 – Illustration of a labral tear of Left Hip

• Asymptomatic tears at least 30% general population, probably 50% in athletes
• Common end outcome of impingement, dysplasia or arthritis but the surgical treatment will differ based on the underlying pathology
• No all are repairable (ripped jeans analogy), with some not as much a tear as more ‘wear and tear’
• Activity modification has poor evidence of efficacy, but high impact and high flexion based activity likely worse
• Therapy should focus on acetabular position (analogous to scapular stabilization therapy for rotator cuff pathology) – hamstrings and core…not clamshells

Injections

• Positive response to corticosteroid injection is 90% accurate for intra-articular hip pathology
• Corticosteroid – 5 RCTs showed pain reduction at 3-4 weeks and 2 reported improvements at 8 weeks in hip OA
• No correlation between degree of response and surgical outcomes however
• Hyaluronic acid – good evidence no better than steroid at 1 month, scarce evidence of efficacy at 3 months, no evidence at 6 months -> not recommended for hip OA
• PRP – very limited evidence

Hip arthroscopy

• An emerging treatment for which the indications are constantly evolving
• FAI symptoms can come and go, so want to refrain from surgery unless symptoms have persisted for at least one year
• OA and hip dysplasia generally do poorly with hip arthroscopy (poor outcomes and high revision rates in those with even mild OA on xray). We don’t yet know how much cartilage damage is too much on an MRI to determine who won’t benefit from a scope
• Outcome for CAM surgery more predictable than PINCER
• Positive prognostic factors = younger age (< 45), male, lower BMI, no OA, previous pain relief with intra-articular injection**
• Although a day surgery and made through small incisions, it’s a different operation than knee and shoulder scopes
• Arthroscopy associated with higher QoL than open treatment for FAI
• Labral surgery continuum = debridement -> repair -> augmentation -> reconstruction -> biologic enhancement
• Hip arthroscopy post-op issues can include infection (higher risk if corticosteroid injection within 3 months), subspine impingement post AIIS avulsion, heterotopic ossification, dislocations, rapid onset of OA, adhesive capsulitis, musculotendinous injuries from portals, and peripheral nerve injury – especially transient pudendal nerve dysfunction (as high as 1/3 of patients) and sciatic and femoral nerve injury due to traction (need approximately 100 lbs of force to distract hip during surgery)
• Post-op rehab is 6 months or longer, return to sport 7 to 8 months, and probably costs $1000-1500 to rehab from a hip scope

Wes Clayden MD CCFP(SEM) Dip Sport Med (October 25, 2019 PR ND)