• anterior capsule thickness
• arthroscopic surgery
• capsule
• heal
• hip
• magnetic resonance imaging

• Femoroacetabular impingement
• Hip joint
• Joint capsule
• Joint instability
• Magnetic resonance imaging

• Humans
• Joint Capsule/diagnostic imaging
• Joint Capsule/pathology
• Hip Joint/diagnostic imaging
• Hip Joint/pathology
• Joint Diseases/diagnostic imaging
• Magnetic Resonance Imaging/methods

• Barbed continuous suture
• Biomechanical tensile test
• Capsule repair
• Suturing materials
• Suturing methods

• Tensile Strength
• Animals
• Sutures
• Suture Techniques
• Swine
• Biomechanical Phenomena
• Materials Testing
• Joint Capsule/surgery
• Humans
• Stress, Mechanical

• Humans
• Arthroscopy
• Femoracetabular Impingement/surgery
• Cross-Sectional Studies
• Joint Capsule/surgery
• Practice Patterns, Physicians'/statistics & numerical data
• Hip Joint/surgery
• Surveys and Questionnaires
• Geography
• Orthopedic Surgeons/statistics & numerical data

• acetabular labrum repair
• cam resection
• capsular repair
• groin pain
• hip arthroscopy
• hip/pelvis/thigh
• hip: femoroacetabular impingement
• osteotomy
• pincer resection
• psoas fractional lengthening

• borderline hip dysplasia
• capsulotomy
• hip arthroscopy
• non‐interportal capsulotomy
• repaired interportal capsulotomy

• Humans
• Arthroscopy/methods
• Female
• Male
• Retrospective Studies
• Adult
• Follow-Up Studies
• Joint Capsule/surgery
• Patient Reported Outcome Measures
• Treatment Outcome
• Hip Dislocation/surgery
• Hip Joint/surgery
• Young Adult

• 81902303 National Natural Science Foundation of China
• JCYJ20210324102815040 Shenzhen Science and Technology Project
• 20213357007 Clinical Research Project of Shenzhen Second People's Hospital

• everted labrum
• femoroacetabular impingement
• hip arthroscopy

• Humans
• Acetabulum/surgery
• Female
• Retrospective Studies
• Male
• Adult
• Arthroscopy
• Patient Reported Outcome Measures
• Young Adult
• Adolescent
• Osteotomy/methods
• Middle Aged
• Treatment Outcome

• Humans
• Arthroscopy/adverse effects
• Arthroscopy/methods
• Acetabulum/injuries
• Acetabulum/pathology
• Acetabulum/surgery
• Hip Dislocation
• Hip Injuries/diagnostic imaging
• Hip Injuries/surgery
• Magnetic Resonance Imaging/methods
• Hip Joint/diagnostic imaging
• Hip Joint/surgery
• Hip Joint/pathology

• Capsule
• Hip
• Magnetic resonance imaging
• Ultrasound

• Humans
• Retrospective Studies
• Hip Joint/surgery
• Acetabulum/surgery
• Joint Capsule/diagnostic imaging
• Ultrasonography

• Humans
• Male
• Female
• Femoracetabular Impingement/diagnostic imaging
• Femoracetabular Impingement/surgery
• Hip Joint/diagnostic imaging
• Hip Joint/surgery
• Retrospective Studies
• Femur/diagnostic imaging
• Femur/surgery
• Bone Diseases
• Arthroscopy/methods

• Capsular management
• Capsular repair
• Capsulotomy
• Femoroacetabular impingement
• Hip arthroscopy
• Hip capsule

• Anterior Approach
• Developmental Dysplasia of the hip
• Hip Joint
• Open reduction
• Surgical Treatment

• D2022083 the Project of the Administration of Traditional Chinese Medicine of Hunan Province
• 2022CR14 the Hospital-level project of Hunan Children's Hospital
• 202204083923 the Scientific Research Project of Hunan Provincial Health Commission
• 202218015914 the Hunan Health Appropriate Technology Promotion Project in 2022

• Anterior capsular defect
• Anterior capsular thickness
• Borderline developmental dysplasia of the hip
• Magnetic resonance imaging

• Borderline dysplasia of hip
• Capsular thickness
• Hip instability
• Iliofemoral ligament
• Intra-substance change

• Male
• Humans
• Female
• Young Adult
• Retrospective Studies
• Hip Dislocation, Congenital/diagnostic imaging
• Hip Dislocation, Congenital/surgery
• Hip Joint/diagnostic imaging
• Hip Joint/surgery
• Femoracetabular Impingement/diagnostic imaging
• Femoracetabular Impingement/surgery
• Hip Dislocation/diagnostic imaging
• Hip Dislocation/surgery
• Arthroscopy/methods
• Treatment Outcome

To compare preoperative hip range of motion (ROM), hip capsular thickness on magnetic resonance imaging (MRI), and bony morphology on radiographs and computed tomography (CT) between patients with and without joint hypermobility as measured by the Beighton Test score (BTS), with subanalysis based on sex and age.

Consecutive patients who underwent hip arthroscopy for a diagnosis of femoroacetabular impingement syndrome with or without dysplasia were retrospectively reviewed. Patient BTS, hip ROM, demographics, surgical data, morphologic measures on radiographs and CT, and MRI findings including hip capsule thickness at various locations were compiled. Multiple statistical tests were performed, including multivariable linear or logistic regression models, while controlling for BTS, age, and sex.

In total, 99 patients were included with a mean age of 29 ± 9.9 years; 62 (62.6%), were female. Forty patients (40.4%) had a BTS ≥4. Female patients (P < .001) and younger patients (26.7 vs 30.9 years, P = .030) were more likely to have a BTS ≥4. Male patients had significantly thicker superior capsules (3.4 mm vs. 2.8 mm, P = .034). BTS was not associated with capsular thickness when controlling for sex. On CT, femoral version (18.9° vs 11.4°, P < .001), and McKibben index (37.8° vs. 28.2°, P < .001) were significantly greater in those with a BTS ≥4. Patients with a BTS ≥4 had more hip internal rotation at 90° of flexion (15.0° vs 10.0°, P < .001), when prone (30.0° vs 20.0°, P = .004), and in extension (10.0° vs. 5.0°, P < .001).

All female patients, regardless of Beighton score, and all patients with a BTS ≥4 indicated for primary hip arthroscopy for femoroacetabular impingement syndrome with or without dysplasia were more likely to have thinner superior hip capsules on MRI and greater hip internal rotation on exam. Bony morphologic differences exist between sexes and between patients with and without hypermobility, likely contributing to differences in ROM.

III, retrospective cohort study.

Hip arthroscopy for treatment of femoroacetabular impingement (FAI) has developed rapidly and has been shown to significantly decrease pain and improve hip function. However, the relationship between hip capsule characteristics and healing after arthroscopic surgery and changes in patient-reported outcomes scores (PROs) for postoperative pain, function, and symptoms is still uncertain.

We retrospectively evaluated consecutive patients who were diagnosed with FAI and underwent hip arthroscopy for treatment in our hospital between May 2018 and November 2020. All patients had preoperative MRI and postoperative MRI at least 6 months after arthroscopy. Hip capsular thickness was measured at the proximal, middle, and distal site of the capsule. PROs and PROs at final follow-up were obtained, including visual analog scale (VAS) for pain and modified Harris Hip Score (mHHS).

A total of 194 patients were included in this study. The mean MRI follow-up time was 14.3 (range, 6–37) months, and the mean clinical follow-up time was 26.1 (range, 12–43) months. Postoperative capsular thickness or net change were not correlated with postoperative PROs and VAS (P > .05). Capsular defect was observed in 17 (8.8%) patients. Patients with capsular defect had a relatively higher BMI (P < .05). Patients with capsular defect had a significant lower mHHS and higher VAS compared with patients with continuous capsule (P < .05). Ninety-one percentage of patients with continuous capsule surpassed minimal clinically important difference (MCID) and 80.8% achieved PASS, but only 58.8% of patients with capsular defect surpassed MCID and 47.1% achieved patient acceptable symptom state (PASS).

Postoperative capsular thickness may not have influence on the clinical outcomes of hip arthroscopy for treatment of FAI. Some capsule of patients who underwent arthroscopic interportal capsulotomy and repair could not heal. Postoperative capsular continuity had a great impact on the clinical outcomes of hip arthroscopy for FAI. Patients with higher BMI may be more likely to have capsule failure to heal.

• Capsule
• Femoroacetabular impingement
• Hip
• Magnetic resonance imaging

• Arthroscopy/methods
• Bone Diseases
• Femoracetabular Impingement/diagnostic imaging
• Femoracetabular Impingement/surgery
• Femur/diagnostic imaging
• Femur/surgery
• Hip Joint/diagnostic imaging
• Hip Joint/surgery
• Humans
• Magnetic Resonance Imaging/methods
• Tomography, X-Ray Computed/methods

Current literature shows no clear answer on the question how to manage the capsule after hip arthroscopy. Regarding patient reported outcome measures there seems to be no difference between capsular repair or unrepaired capsulotomy.

To evaluate and compare the integrity of the hip capsule measured on a magnetic resonance imaging (MRI) scan after capsular repair or unrepaired capsulotomy.

A case series study was performed; a random sample of patients included in a trial comparing capsular repair vs unrepaired capsulotomy had a postoperative MRI scan. The presence of a capsular defect and gap size were independently evaluated on MRI.

A total of 28 patients (29 hips) were included. Patient demographics were comparable between treatment groups. There were 2 capsular defects in the capsular repair group and 7 capsular defects in the unrepaired capsulotomy group (P = 0.13). In the group of patients with a defect, median gap sizes at the acetabular side were 5.9 mm (range: 2.7-9.0) in the repaired and 8.0 mm (range: 4.5-18.0) in the unrepaired group (P = 0.462). At the muscular side gap sizes were 6.6 mm (range: 4.1-9.0) in the repaired group and 11.5 mm (range: 3.0-18.0) in the unrepaired group (P = 0.857). The calculated Odds ratio (OR) for having a capsular defect with an increasing lateral center-edge (CE) angle was 1.12 (P = 0.06). The OR for having a capsular defect is lower in the group of patients that underwent a labral repair with an OR of 0.1 (P = 0.05).

There is no significant difference in capsular defects between capsular repair or unrepaired capsulotomy. Regarding clinical characteristics our case series shows that a larger CE angle increases the likelihood of a capsular defect and the presence of a labral repair decreases the likelihood of a capsular defect.

• Hip
• Arthroscopy
• Magnetic resonance imaging
• Capsule
• Thickness

• UL1 TR002538 NCATS NIH HHS

• Arthroscopy
• Bilateral
• Complications
• FAI
• Hip
• Simultaneous
• Staged

• Hip arthroscopy
• Hip arthroscopy revision
• Hip capsular deficiency
• Hip capsular insufficiency
• Hip capsular laxity
• Hip capsule
• Hip instability
• Hip microinstability

To quantify the magnetic resonance arthrography (MRA) capsular morphologic findings associated with postarthroscopy hip instability.

Among patients with clinically significant iatrogenic hip instability at a single center, patients with preindex and postindex surgery MRAs were identified. These MRAs were compared regarding effective intracapsular volume calculated by semi-automated 3-dimensional pixel intensity region segmentation, 2-dimensional anterior proximal intracapsular area in the femoral neck axial plane reconstruction, maximal anterior fluid pocket depth, capsule retraction distance, and capsular instability grade. Morphological measurements were conducted using Horos image processing software. Paired t-test, paired Wilcoxon signed rank test, and the McNemar test were used for identifying statistical significance.

In 42 patients, mean effective intracapsular volume was significantly greater in the postindex surgery MRAs (19.44 cm³ vs 17.26 cm³; P = .006). Proximal anterosuperior (12-3 o'clock) intracapsular area was also significantly greater after index surgery (2.84 cm² vs 1.43 cm²; P < .001. Proximal anteroinferior (3-6 o'clock) intracapsular area (1.34 cm² vs 0.97 cm²; P = .002), capsule deficiency grade (P < .001), anterior capsule retraction distance (4.83 mm vs 0.34 mm; P < .001), and maximum anterior fluid depth (8.33 mm vs 4.90 mm; P <.001) were also significantly increased after index surgery.

In comparison to the preoperative state, iatrogenic hip instability is associated with MRA findings that include increases in total effective intracapsular volume, proximal anterosuperior and anteroinferior intracapsular cross-sectional area, maximum proximal anterosuperior fluid depth, and capsule retraction distance.

Level IV, diagnostic case series.

To evaluate the midterm outcomes and the capsular healing in patients who had interportal capsulotomy versus periportal capsulotomy of hip arthroscopy.

Retrospectively reviewed 33 patients with labral tear received hip arthroscopy, with an average age of 41 (27‐67) years, including 13 cases of Cam deformity and three cases of Pincer deformity. All patients had positive sign of flexion adduction internal rotation or flexion abduction external rotation. With MRI and radiographic (CT, X plain) imageological examination. MRI showed that all patients had labral tear. Radiographic finding (CT, X plain) showed the pathological changes of acetabular and femoral neck osteophyte. One group with 23 patients were treated with periportal capsulotomy. Another group with 10 patients were treated with interportal capsulotomy. All patients did not close the capsule. Clinical outcomes were measured with the Hip Outcome Score Activities of Daily Living (HOS‐ADL) and the modified Harris Hip Score (mHHS), patient satisfaction measured with visual analogue scale (VAS). The healing of the capsule was evaluated by MRI. MRI showed continuous capsular indicated healing, discontinuous capsular indicated unhealing. Postoperatively 6 months, mHHS and HOS‐ADL were obtained. Randomized controlled trials were used in this study for analysis.

All patients were followed up with average time of 9.3 months(3‐29 months). The postoperative symptoms were obviously relieved, the VAS decreased from (4.9 ± 0.6) to (1.2 ± 0.2) after 3 months postoperative. Follow up 6 months post‐operation, patients in the interportal group, the mHHS and HOS‐ADL scores improvement were respectively 69.4 ± 9.3 & 70 ± 8.8 pre‐operation, and 92.5 ± 5.0 & 86.6 ± 5.4 post‐operation (P < 0.05); Patients in the periportal group, the mHHS and HOS‐ADL scores improvement were respectively 69.9 ± 15.8, 68.1 ± 15.0 pre‐operation, and 90.1 ± 9.3 & 86.7 ± 7.9 post‐operation (P < 0.05).The differences were statistically significant. Six months after operation, MRI showed that 23 patients with periportal capsulotomy, the capsule have healed, without other complications. Three of the ten patients with interportal capsulotomy were healed and seven were not.

Interportal and periportal capsulotomy had good outcomes. The technique of periportal capsulotomy had little damage to the joint capsule. Although the capsule did not close, the capsule healed well in postoperative follow‐up. The nonunion rate of the joint capsule was high in the interportal capsulotomy without close the capsule.

• Capsular healing
• Hip arthroscopy
• Interportal capsulotomy
• Outcomes
• Periportal capsulotomy

The zona orbicularis, which comprises the inner circular fibers of the joint capsule, is vital for hip stability in distraction. Despite the proximity of the whole joint capsule to the zona orbicularis, their anatomical relationship remains unclear. The aim of this study is to investigate the characteristics of the inner side of the joint capsule comprehensively. Twelve hips from nine bodies donated to science were examined. Six and three of the donated bodies, respectively, were embalmed using 8% formalin and Thiel's method. The joint capsules in three formalin‐embalmed bodies were sturied by micro‐computed tomography. During formalin fixation of six hips from these three bodies, one side was maintained at hip extension and the other at flexion. The remaining three formalin‐embalmed bodies were examined histologically. Micro‐computed tomography images revealed that the inward protrusion of the joint capsule narrowed the articular cavity, and the ratio of its narrowest area to that of the femoral neck was less at hip extension than at hip flexion. The Thiel's method specimens showed that the inner surface of the joint capsule protruded inward toward the femoral neck during hip extension. This inward protrusion was not histologically independent of the joint capsule. The zona orbicularis was interpreted as the inward protrusion caused by dynamic change of the joint capsule, rather than the local collar. In other words, the joint capsule could change its morphology dynamically depending on the hip position.

• anatomy
• hip joint
• joint capsule
• musculoskeletal system

• Arthroscopy
• Femoroacetabular impingement
• Hip
• Peripheral compartment

• 2-year outcomes
• T-capsulotomy
• femoroacetabular impingement syndrome
• hip arthroscopy
• interportal capsulotomy

• adult hip dysplasia
• borderline hip dysplasia
• hip arthroscopy
• lateral center-edge angle
• periacetabular osteotomy

• Capsule repair
• capsulotomy
• hip arthroscopy
• hip instability
• meta-analysis
• systemic review
• unrepaired capsule

• Arthroscopy
• Capsule
• Hip
• Thickness

• Capsular management
• Capsule
• Hip arthroscopy
• Patient reported outcomes (PROs)
• Plication
• Repair

• capsular closure
• hip arthroscopy
• hip instability
• labral tear

• Activities of Daily Living
• Adult
• Arthroscopy/methods
• Female
• Femur/surgery
• Hip Joint/surgery
• Humans
• Male
• Middle Aged
• Patient Reported Outcome Measures
• Postoperative Period
• Prospective Studies
• Reoperation/statistics & numerical data
• Treatment Outcome
• Young Adult

➤Hip joint capsular ligaments (iliofemoral, ischiofemoral, and pubofemoral) play a predominant role in functional mobility and joint stability. ➤The zona orbicularis resists joint distraction (during neutral positions), and its aperture mechanism stabilizes the hip from adverse edge-loading (during extreme hip flexion-extension). ➤To preserve joint function and stability, it is important to minimize capsulotomy size and avoid disrupting the zona orbicularis, preserve the femoral head size and neck length, and only repair when or as necessary without altering capsular tensions. ➤It is not fully understood what the role of capsular tightness is in patients who have cam femoroacetabular impingement and if partial capsular release could be beneficial and/or therapeutic. ➤During arthroplasty surgery, a femoral head implant that is nearly equivalent to the native head size with an optimal neck-length offset can optimize capsular tension and decrease dislocation risk where an intact posterior hip capsule plays a critical role in maintaining hip stability.

• Arthroplasty, Replacement, Hip/methods
• Cadaver
• Dissection
• Female
• Hip Joint/anatomy & histology
• Hip Joint/physiopathology
• Hip Joint/surgery
• Humans
• Imaging, Three-Dimensional
• Joint Capsule/anatomy & histology
• Joint Capsule/surgery
• Joint Instability/prevention & control
• Male
• Orthopedic Procedures/methods
• Range of Motion, Articular/physiology

• Wellcome Trust