Skip to main content
Log in

Postoperative alpha angle not associated with patient-centered midterm outcomes following hip arthroscopy for FAI

  • Hip
  • Published:
Knee Surgery, Sports Traumatology, Arthroscopy Aims and scope

Abstract

Purpose

The most commonly used parameter for defining cam-type femoroacetabular impingement(FAI) has been the alpha angle. The purpose of this study was to determine if patient-reported outcomes 5 years following hip arthroscopy for FAI were associated with postoperative alpha angle. We hypothesized that patient-reported outcomes would not be influenced by postoperative alpha angle in patients with FAI.

Methods

230 patients had primary hip arthroscopy for FAI and chondrolabral dysfunction. The median age was 40 years (range 18–69). All patients had preoperative and 1 day postoperative alpha angles recorded. At minimum 5 years following arthroscopy, all patients completed an online questionnaire that included the modified Harris Hip score(MHHS), WOMAC, HOS ADL, HOS Sport, SF12 and patient satisfaction. This study was IRB approved. Patients were grouped into two, based on their postoperative alpha angle: <55° (n = 158) and ≥ 55° (n = 56).

Results

The median preoperative alpha angle was 72° (range 50°–105°) and the median postoperative alpha angle was 45° (range 30°–100°). The postoperative alpha angle did not correlate with any outcome measure. The median preoperative alpha angle in the < 55° group was 71° and in ≥ 55° group the median was 74° (p = 0.044). The median follow-up was 5.1 years (range 5–7). The median mHHS was 85 (range 47–100) in the < 55° and 85 (range 54–100) in the ≥ 55° group (n.s); WOMAC was 5 (range 0–73) in the < 55° and 4.5 (range 1–57) in the ≥ 55° group(n.s); HOS ADL was 95 (range 31–100) in the < 55° and 96 (range 50–100) in the ≥ 55° group (n.s); HOS Sport was 88 (range 0–100) in the < 55° and 88 (range 13–100) in the ≥ 55° group (n.s) Median patient satisfaction was 9 (range 1–10) in both groups.

Conclusion

This study shows no statistically significant differences between the investigated patient-reported outcome scores at a 5 years postoperatively in relation to a correction of the alpha angle to 55°. While alpha angle has been shown to be an excellent preoperative diagnostic tool, the postoperative angle does not correlate with midterm outcomes or the development of osteoarthritis based on patient symptoms. The amount of osteoplasty should be based on dynamic examination at arthroscopy, and not by alpha angle.

Level of evidence

III Case–control, retrospective comparative study.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

Abbreviations

FAI:

Femoroacetabular impingement

AA:

Apha angle

FABER:

Flexion abduction external rotation

HOS:

Hip outcome score

ADL:

Activities of daily living

mHHS:

Modified Harris hip score

References

  1. Bhatia S, Nowak DD, Briggs KK, Patterson DC, Philippon MJ (2016) Outerbridge Grade IV cartilage lesions in the hip identified at arthroscopy. Arthroscopy 32:814–819

    Article  PubMed  Google Scholar 

  2. Beck M, Kalhor M, Leunig M, 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 Jt Surg Br 87:1012–1018

    Article  CAS  Google Scholar 

  3. Brunner A, Horisberger M, Herzog RF (2009) Evaluation of a computed tomography-based navigation system prototype for hip arthroscopy in the treatment of femoroacetabular cam impingement. Arthroscopy 25:382–391

    Article  PubMed  Google Scholar 

  4. Clohisy JC, Carlisle JC, Beaule MD, Kim YJ, Trousdale RT, Sierra RJ, Leunig M, Schoenecker PL, Millis MB (2008) A systematic approach to the plain radiographic evaluation of the young adult hip. J Bone Jt Surg Am 90(suppl 4):47–66

    Article  Google Scholar 

  5. de Sa D, Urquhart N, Philippon M, Ye JE, Simunovic N, Ayeni OR (2014) Alpha angle correction in femoroacetabular impingement. Knee Surg Sports Traumatol Arthrosc 22:812–821

    Article  PubMed  Google Scholar 

  6. Degen RM, Nawabi DH, Bedi A, Kelly BT (2017) Radiographic predictors of femoroacetabular impingement treatment outcomes. Knee Surg Sports Traumatol Arthrosc 25:36–44

    Article  PubMed  Google Scholar 

  7. Frank JM, Chahla J, Mitchell JJ, Soares E, Philippon MJ (2016) Remplissage of the femoral head-neck junction in revision hip arthroscopy: a technique to correct excessive cam resection. Arthrosc Tech 5:e1209–e1213

    Article  PubMed  PubMed Central  Google Scholar 

  8. Ganz R, Parvizi J, Beck M, Leunig M, Notzli H, Siebenrock KA (2003) Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res 417:112–120

    Google Scholar 

  9. Haldane CE, Ekhtiari S, de Sa D, Simunovic N, Ayeni OR (2017) Preoperative physical examination and imaging of femoroacetabular impingement prior to hip arthroscopy-a systematic review. J Hip Preserv Surg 4:201–213

    Article  PubMed  PubMed Central  Google Scholar 

  10. Johnston TL, Schenker ML, Briggs KK, Philippon MJ (2008) The relationship between offset angle alpha and hip chondral injury in femoroacetabular impingement. Arthroscopy 24:669–675

    Article  PubMed  Google Scholar 

  11. Kappe T, Kocak T, Bieger R, Reichel H, Fraitzl CR (2011) Radiographic risk factors for labral lesions in femoroacetabular impingement. Clin Orthop Relat Res 469:3241–3247

    Article  PubMed  PubMed Central  Google Scholar 

  12. Locks R, Chahla J, Mitchell JJ, Soares E, Philippon MJ (2016) Dynamic hip examination for assessment of impingement during hip arthroscopy. Arthrosc Tech 5:e1367–e1372

    Article  PubMed  PubMed Central  Google Scholar 

  13. Martin RL, Kelly BT, Philippon MJ (2006) Evidence of validity for the hip outcome score. Arthroscopy 22:1304–1311

    Article  PubMed  Google Scholar 

  14. Martin RL, Philippon MJ (2008) Evidence of relibility and responsiveness for the hip outcome score. Arthrsocopy 24:676–682

    Article  Google Scholar 

  15. Meyer DC, Beck M, Ellis T, Ganz R, Leunig M (2006) Comparison of six radiographic projections to assess femoral head/neck asphericity. Clin Orthop Relat Res 445:181–185

    PubMed  Google Scholar 

  16. Neumann M, Cui Q, Siebenrock KA, Beck M (2009) Impingement-free hip motion: the ‘normal’ angle alpha after osteochondroplasty. Clin Orthop Relat Res 467:699–703

    Article  PubMed  Google Scholar 

  17. Notzli HP, Wyss TF, Stoecklin CH, Schmid MR, Treiber K, Hodler J (2002) The contour of the femoral head-neck junction as a predictor for the risk of anterior impingement. J Bone Jt Surg Br 84:556–560

    Article  CAS  Google Scholar 

  18. Philippon MJ, Briggs KK, Yen YM, Kuppersmith DA (2009) Outcomes following hip arthroscopy for femoroacetabular impingement and associated chondrolabral dysfunction: minimum 2 year follow-up. J Bone Jt Surg Br 91:16–23

    Article  CAS  Google Scholar 

  19. Philippon MJ, Maxwell RB, Johnston TL, Schenker M, Briggs KK (2007) Clinical Presentation of Femoroacetabular Impingement. Knee Surg Sports Traumatol Arthrosc 15:1041–1047

    Article  PubMed  Google Scholar 

  20. Philippon MJ, Schenker ML (2006) A new method for arthroscopic rim trimming and labral repair. Clin Sports Med 25:293–297

    Article  PubMed  Google Scholar 

  21. Philippon MJ, Stubbs AJ, Schenker ML, Maxwell RB, Ganz R, Leunig M (2007) Arthroscopic management of femoroacetabular impingement: osteoplasty technique and literature review. Am J Sports Med 35:1571–1580

    Article  PubMed  Google Scholar 

  22. Redmond JM, Gupta A, Hammarstedt JE, Stake CE, Dunne KF, Domb BG (2015) Labral injury: radiographic predictors at the time of hip arthroscopy. Arthroscopy 31:51–56

    Article  PubMed  Google Scholar 

  23. Skendzel JG, Philippon MJ, Briggs KK, Goljan P (2014) The effect of joint space on midterm outcomes after arthroscopic hip surgery for femoroacetabular impingement. Am J Sports Med 30:1127–1133

    Article  Google Scholar 

  24. Sankar WN, Nevitt M, Parvizi J, Felson DT, Agricola R, Leunig M (2013) Femoroacetabular impingement: defining the condition and its role in the pathophysiology of osteoarthritis. J Am Acad Orthop Surg 21(Suppl 1):S7–S15

    PubMed  Google Scholar 

  25. Stähelin L, Stähelin T, Jolles BM, Herzog RF (2008) Arthroscopic offset restoration in femoroacetabular cam impingement: accuracy and early clinical outcome. Arthroscopy 24:51–57

    Article  PubMed  Google Scholar 

Download references

Funding

No fees, funding or salary may gain or lose financially from this publication.

Author information

Authors and Affiliations

Authors

Contributions

KKB participated in study conception and design, carried out acquisition of data and analysis and interpretation of data, and carried out drafting and revising of the manuscript. ES participated in study conception and design, interpretation of data and participated in drafting and revising the manuscript. SB participated in study conception and design, interpretation of data and participated in drafting and revising the manuscript. MJP participated in study conception and design, collected data, participated in interpretation of data and participated in drafting and revising of the manuscript. All authors have given final approval of the manuscript submitted and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Corresponding author

Correspondence to Karen K. Briggs.

Ethics declarations

Conflict of interest

No financial or non-financial competing interest exists for this manuscript. The manuscript was not influenced by personal or financial relationship with other people or organizations.

Ethical approval

This study was approved by the Internal Review Board/Ethics Committee at the Vail Valley Hospital.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Briggs, K.K., Soares, E., Bhatia, S. et al. Postoperative alpha angle not associated with patient-centered midterm outcomes following hip arthroscopy for FAI. Knee Surg Sports Traumatol Arthrosc 27, 3105–3109 (2019). https://doi.org/10.1007/s00167-018-4933-3

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00167-018-4933-3

Keywords

Navigation