Purpose
To investigate the relation of hip capsular thickness as measured on preoperative
magnetic resonance imaging (MRI) and intraoperative hip joint axial distraction distance
on an examination under anesthesia.
Methods
A retrospective review of primary arthroscopic hip procedures performed between November
2018 and June 2021 was conducted. The inclusion criteria included a diagnosis of femoroacetabular
impingement syndrome and preoperative radiographic imaging and MRI. Fluoroscopic images
were obtained at 0 lb and 100 lb of axial traction force. Total distraction distance
was calculated by comparing the initial joint space with the total joint space at
100 lb. Hip capsular thickness was measured on MRI. Analysis was conducted using multiple
linear regression, independent-samples t tests, and Mann-Whitney U tests.
Results
Eighty patients were included. Bivariable regression showed an association between
an increased distraction distance and female sex (β = 4.303, R = 0.561, P < .001), as well as decreased anterior axial (β = –1.291, R = 0.365, P < .001) and superior coronal (β = –1.433, R = 0.501, P < .001) capsular thickness. Multivariable regression (R = 0.645) showed an association between an increased distraction distance and female
sex (β = 3.175, P < .001), as well as decreased superior coronal capsular thickness (β = –0.764, P = .022). Independent-samples t tests showed that female patients had significantly decreased superior coronal capsular
thickness (2.92 ± 1.14 mm vs 3.99 ± 1.15 mm, P < .001).
Conclusions
Female sex and decreased hip capsular thickness in the superior aspect of the coronal
plane on magnetic resonance scans were found to be predictors of increased hip joint
axial distraction distance on examination under anesthesia prior to hip arthroscopy,
with anterior axial capsular thickness being a moderate predictor. Poor predictors
of distraction distance were posterior axial and inferior coronal capsular thickness,
age, body mass index, and lateral center-edge angle. Female patients were also found
to have thinner hip capsules in the superior region, which may explain the association
between female patients and increased distraction. These findings further characterize
the relation between capsular thickness and hip laxity.
Level of Evidence
Level IV, case series.
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References
- An anatomic arthroscopic description of the hip capsular ligaments for the hip arthroscopist.Arthroscopy. 2011; 27: 628-636
- Atraumatic hip instability.JBJS Rev. 2016; 4: e3
- Microinstability of the hip—Gaining acceptance.J Am Acad Orthop Surg. 2019; 27: 12-22
- Hip capsular deficiency—A cause of post-surgical instability in the revision setting following hip arthroscopy for femoroacetabular impingement.Curr Rev Musculoskelet Med. 2021; 14: 351-360
- The effect of capsulotomy and capsular repair on hip distraction: A cadaveric investigation.Arthroscopy. 2017; 33: 559-565
- Effects of capsular reconstruction with an iliotibial band allograft on distractive stability of the hip joint: A biomechanical study.Am J Sports Med. 2018; 46: 3429-3436
- Vertical extension of the T-capsulotomy incision in hip arthroscopic surgery does not affect the force required for hip distraction: Effect of capsulotomy size, type, and subsequent repair.Am J Sports Med. 2018; 46: 3127-3133
- Capsulotomy size affects hip joint kinematic stability.Arthroscopy. 2016; 32: 1571-1580
- Capsular repair during hip arthroscopy demonstrates restoration of axial distraction resistance in an in vivo intraoperative testing model.J Bone Joint Surg Am. 2021; 103: 1977-1985
- Complete capsular repair restores native kinematics after interportal and T-capsulotomy.Am J Sports Med. 2019; 47: 1451-1458
- Biomechanical evaluation of capsulotomy, capsulectomy, and capsular repair on hip rotation.Arthroscopy. 2015; 31: 1511-1517
- Biomechanical assessment of hip capsular repair and reconstruction procedures using a 6 degrees of freedom robotic system.Am J Sports Med. 2017; 45: 1745-1754
- Improved outcomes after hip arthroscopic surgery in patients undergoing T-capsulotomy with complete repair versus partial repair for femoroacetabular impingement: A comparative matched-pair analysis.Am J Sports Med. 2014; 42: 2634-2642
- Midterm outcomes following repair of capsulotomy versus nonrepair in patients undergoing hip arthroscopy for femoroacetabular impingement with labral repair.Arthroscopy. 2019; 35: 1828-1834
- Patient-reported outcomes of capsular repair versus capsulotomy in patients undergoing hip arthroscopy: Minimum 5-year follow-up—A matched comparison study.Arthroscopy. 2018; 34: 853-863.e1
- Hip dislocation or subluxation after hip arthroscopy: A systematic review.Arthroscopy. 2016; 32: 1428-1434
- Patient-specific parameters associated with traction in primary and revision hip arthroscopic surgery.Orthop J Sports Med. 2018; 62325967118807707
- Gross instability after hip arthroscopy: An analysis of case reports evaluating surgical and patient factors.Arthroscopy. 2016; 32: 1196-1204.e1
- Hip capsular closure.Am J Sports Med. 2017; 45: 434-439
- Prevalence of generalized ligamentous laxity in patients undergoing hip arthroscopy: A prospective study of patients’ clinical presentation, physical examination, intraoperative findings, and surgical procedures.Am J Sports Med. 2019; 47: 885-893
- Capsular laxity of the hip: Findings at magnetic resonance arthrography.Arthroscopy. 2013; 29: 1615-1622
- Capsular thinning on magnetic resonance arthrography is associated with intra-operative hip joint laxity in women.J Hip Preserv Surg. 2020; 7: 298-304
- Which two-dimensional radiographic measurements of cam femoroacetabular impingement best describe the three-dimensional shape of the proximal femur?.Clin Orthop Relat Res. 2019; 477: 242-253
- Relationship between the lateral center-edge angle and 3-dimensional acetabular coverage.Orthop J Sports Med. 2017; 52325967117700589
- Discrepancies in measuring acetabular coverage: Revisiting the anterior and lateral center edge angles.J Hip Preserv Surg. 2015; 2: 280-286
- What are the radiographic reference values for acetabular under- and overcoverage?.Clin Orthop Relat Res. 2015; 473: 1234-1246
- Previous arthroscopic hip surgery increases axial distractibility compared to the native contralateral hip and may suggest instability.Arthroscopy. 2022; 38: 1466-1477
- Statistical tables.W. H. Freeman, San Francisco1995
- A guideline of selecting and reporting intraclass correlation coefficients for reliability research.J Chiropr Med. 2016; 15: 155-163
- Generalized joint hypermobility is predictive of hip capsular thickness.Orthop J Sports Med. 2017; 52325967117701882
- The capsule’s contribution to total hip construct stability—A finite element analysis.J Orthop Res. 2011; 29: 1642-1648
- Arthroscopic capsulotomy, capsular repair, and capsular plication of the hip: Relation to atraumatic instability.Arthroscopy. 2013; 29: 162-173
- Arthroscopic management of femoroacetabular impingement: Osteoplasty technique and literature review.Am J Sports Med. 2007; 35: 1571-1580
- Microinstability of the hip—It does exist: Etiology, diagnosis and treatment.J Hip Preserv Surg. 2015; 2: 123-125
- Patient-specific factors influencing the traction forces in hip arthroscopy.Arch Orthop Trauma Surg. 2017; 137: 81-87
Article info
Publication history
Published online: May 09, 2022
Accepted:
April 19,
2022
Received:
November 24,
2021
Footnotes
See commentary on page 3141
The authors report the following potential conflicts of interest or sources of funding: S.K.A. receives personal fees for consulting from Stryker; personal fees for travel and lodging from Stryker; personal fees for food and beverage from Stryker and Smith & Nephew; and personal fees for education support from Active Medical, outside the submitted work. Full ICMJE author disclosure forms are available for this article online, as supplementary material.
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© 2022 by the Arthroscopy Association of North America
