Borderline Dysplasia After Primary Hip Arthroscopy with Capsular Plication and Labral Preservation: Ten-Year Survivorship and Patient-Reported Outcomes

The Principles of Hip Joint Preservation

The three primary factors involved in preservation of the hip joint include femoroacetabular impingement (FAI), hip dysplasia/instability, and femoral torsion abnormalities. Each of these factors affects the health of the acetabular labrum and femoroacetabular cartilage. The appropriate surgical treatments for each of these factors include arthroscopic or open femoroplasty/acetabuloplasty for FAI, periacetabular osteotomy for hip dysplasia/instability, and derotational femoral osteotomy for femoral torsion abnormalities. When evaluating patients with prearthritic hip conditions, orthopaedic surgeons should be aware of the various factors involved in hip joint preservation and, if surgery is indicated, the surgeon should be sure to address all factors that need surgical treatment rather than focusing on the commonly diagnosed issue or visible injury, for example, a labral tear. If any of these factors is ignored, the hip joint may not thrive. The purpose of this review was to explain the importance of the most common factors involved in hip joint preservation and the appropriate surgical treatments for pathology in these factors.

A retrospective study of arthroscopic treatment for patients with bordline developmental dysplasia of the hip

PURPOSE

Hip arthroscopy is effective in treating bordline developmental dysplasia of the hip (BDDH), but there are only a few clinical reports in China, and its postoperative failure rate is still a problem that cannot be ignored. The aim of this study was to analyze the clinical effect of hip arthroscopy in BDDH treatment in China and to explore the risk factors influencing the efficacy of hip arthroscopy in BDDH treatment.

METHODS

All of 22 cases of BDDH treated with arthroscopy in our hospital from November March 2017 to February 2022 were analyzed retrospectively, including ten males and 12 females, with an average age of 34.7 ± 9.5 years (19-53 years). All patients underwent arthroscopic treatment with acetabular plasty, labral repair, femoral osteoplasty, and capsular plication. Visual Analogue Scale (VAS), modified Harris Hip Scores (mHHS), Hip Outcome Score-activities of Daily Living (HOS-ADL) and International Hip Outcome Tool-12 (iHOT-12) were measured before operation and at the follow-up, and statistical analysis was performed. The Minimum clinically significant difference (MCID) and Patient Acceptable Symptom State (PASS) were also obtained.

RESULTS

22 patients were followed up, and the follow-up time was ≥ one year, with an average of 21.4 ± 8.2 months. The VAS score decreased from 5.27 ± 1.58 points before surgery to 1.96 ± 0.92 points at the follow-up, and the difference was statistically significant (t = 9.05,P < 0.001). The mHHS score increased from 64.84 ± 13.58 points before surgery to 90.4 ± 10.11 points at the follow-up, and the difference was statistically significant (t=-7.07, P < 0.001). The HOS-ADL score increased from 68.92 ± 11.76 points before surgery to 88.91 ± 9.51 points at the follow-up, and the difference was statistically significant (t=-8.15,P < 0.001). The iHOT-12 score increased from 49.32 ± 12.01 points before surgery to 79.61 ± 15.89 points at the follow-up, and the difference was statistically significant (t=-7.66,P < 0.001). The MCID (mHHS) and MCID (HOS-ADL) were 81.8% and 77.3% respectively, and the PASS (mHHS) and PASS (HOS-ADL) were 86.4% and 72.7% respectively at the follow-up.

CONCLUSION

Hip arthroscopy can achieve good short-term outcomes in the treatment of BDDH.

LEVEL OF EVIDENCE

IV Therapeutic Study.

Editorial Commentary: Arthroscopic Treatment of Mild Hip Dysplasia Can Result in Excellent Outcome and Avoid More Invasive Periacetabular Osteotomy

Several mechanisms either support or decrease stability of the hip joint. Primary stability of the hip comes from bony coverage of the femoral head, influenced by acetabular version and femoral antetorsion. In addition, soft tissue structures such as the acetabular labrum, the ligamentum teres, and the hip capsule play a significant role in maintaining joint stability. Untreated hip instability may lead to pathological force transmission between the acetabular socket and femoral head, and subluxation resulting in osteoarthritis. Historically, pelvic and/or femoral osteotomies have been performed to increase hip stability and prevent joint degeneration. However, osteotomies do not address soft tissue instability or lesions of intra-articular structures, which could explain symptoms following bony correction. Furthermore, the rate of combined pathologies resulting in hip instability and femoroacetabular impingement syndrome (FAIS) is high. Modern hip arthroscopy enables reconstruction and stabilization of soft tissue structures and the correction of bony pathologies caused by FAIS. Minimally invasive procedures can help avoid overtreatment and unnecessary risks associated with more invasive osteotomies. However, in cases of ongoing symptoms after arthroscopic treatment for mild instability, or for patients with severe dysplasia, concomitant PAO and arthroscopy can combine bony correction of a PAO with intra-articular therapies of hip arthroscopy.

Risk Factors for Failure of Hip Arthroscopy in Patients with Borderline Dysplasia include a Tönnis angle ≥ 15 degrees, Age ≥ 40-42 years, Female Sex, Anterior Wall Index < 0.35, Labral Debridement, and Preexisting Hip Osteoarthritis: A Systematic Review

PURPOSE

To systematically review the literature to determine potential risk factors for failure of hip arthroscopy (HA) in patients with borderline hip dysplasia (BHD).

METHODS

A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed, the Cochrane Library, and Embase to identify English language clinical studies reporting on patients with BHD undergoing HA from 2003 to 2023. The search terms used were: (borderline OR mild) AND hip AND (arthroscopy OR dysplasia) AND failure. The primary outcomes assessed were risk factors reported by each study for failure of a HA-only approach in BHD patients.

RESULTS

Fourteen studies (8 level III, 6 level IV) met inclusion criteria, totaling 749 hips. Patient age ranged from 29.8 to 39.2 years with a mean follow-up ranging from 24.0 to 144.0 months. The overall percentage of females ranged from 11.8 to 100.0%. Overall, the clinical failure rate ranged from 0 to 53.3% and the reoperation rate ranged from 0 to 44.0%. The predominant predictors of poor outcomes following HA alone included Tönnis angle ≥ 15°, age ≥ 40-42 years at surgery, and female sex. Other risk factors for failure were preoperative clinical arthritis, grade 3 or 4 articular cartilage changes to the femoral head or acetabulum, an anterior wall index (AWI) < 0.35, and labral debridement. Revision procedures performed included revision HA (n=88, 0-28.0%), total hip arthroplasty (n=55, 0-23.7%), and endoscopic shelf acetabuloplasty (n=5, 0-11.0%). One study included an additional 9 patients converting to either PAO or total hip arthroplasty (THA) without distinguishing between the two.

CONCLUSION

For patients with BHD, Tönnis angle ≥ 15°, age ≥ 40-42 years at surgery, female sex, AWI < 0.35, labral debridement, and preexisting hip osteoarthritis are common risk factors for treatment failure following isolated HA.

LEVEL OF EVIDENCE

IV, systematic review of level III-IV studies.

Circumferential Labral Reconstruction With Knotless All-Suture Anchors Restores Hip Distractive Stability: A Cadaveric Biomechanical Analysis

BACKGROUND

The essential component of managing femoroacetabular impingement involves restoration of the original labral function. Circumferential labral reconstruction (CLR) has shown positive results. However, biomechanical studies of CLR are limited and have not established the efficacy of the modern knotless all-suture anchor (ASA) pull-through technique.

HYPOTHESES

(1) CLR with knotless ASA fixation will restore native labral suction seal biomechanics; (2) tensioning the ASA to a high-tension state will increase the peak distractive force.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight fresh-frozen human cadaveric hips were dissected free of all soft tissue except the native labrum and transverse acetabular ligament. On an electromechanical testing system, the hips were compressively loaded to 250 N to initiate a suction seal and distracted at a rate of 10 mm/s until rupture of the suction seal. Hips were tested in 4 states: intact labrum, full labral removal, knotless CLR with moderate anchor tension, and CLR with high anchor tension. Peak distractive force (in newtons) was compared using repeated measures analysis of variance (P < .05). Acetabular bevel angles (θ) were measured at labral clockface positions outside the transverse acetabular ligament using a 3-dimensional digitizer stylus after rim preparation. Linear regression plots compared θ and peak distractive force in the CLR state.

RESULTS

Peak force values were 138.5 ± 13.6 N (mean ± SE) for the intact labrum, 18.4 ± 2.79 N for labral excision, 95.4 ± 23.3 N for moderate-tension CLR, and 126.2 ± 27.3 N for high-tension CLR. Significant differences were observed only when full labral removal was compared with the other conditions: intact (P < .001), moderate-tension CLR (P = .016), and high-tension CLR (P = .002). Steeper acetabular bevel angles (smaller θ) were correlated with greater suction seal restoration (P < .05).

CONCLUSION

CLR restored distractive stability on average to 82.0% of the intact value after labral deficiency. Retensioning did not significantly increase peak distractive forces.

CLINICAL RELEVANCE

These findings provide biomechanical validation supporting CLR using knotless ASAs in an effort to minimize volumetric bone loss and provide other surgical advantages. The prepared rim's bevel angle may be an important variable to optimize for improved suction seal restoration.

Radiographically Apparent Acetabular Sourcil Landmarks Are Created by Comparable Regions of the Pelvis With Extraarticular Bone Variably Confounding Estimates of Joint Coverage

BACKGROUND

The severity of hip dysplasia is characterized by radiographic measurements that require user definition of the acetabular sourcil edge, a bony landmark for which the corresponding three-dimensional (3D) anatomy is not well defined in any imaging plane.

QUESTIONS/PURPOSES

To use digitally reconstructed radiographs to determine: (1) What 3D anatomy is contributing to the "acetabular sourcil" location used to make lateral center-edge angle (LCEA) and anterior center-edge angle (ACEA) measurements in standing AP and false-profile radiographic views, respectively? (2) How do intraobserver and interobserver agreement in LCEA and ACEA translate into agreement of the 3D anatomy being evaluated? (3) How distinct are regions around the acetabular rim circumference that are evaluated by LCEA and ACEA measurements on radiographs?

METHODS

Between January 2018 and May 2019, 72 patients were indicated for periacetabular osteotomy to treat hip dysplasia or acetabular retroversion at our institution. From these patients, a series of 10 patients were identified of the first 12 patients in 2018 who were treated with periacetabular osteotomy, excluding two with missing or low-quality clinical imaging. A second series of 10 patients was identified of the first 11 patients in 2019 who were treated with periacetabular osteotomy and concurrent hip arthroscopy, excluding one who was missing clinical imaging. Pelvis and femoral bone surface models were generated from CT scans of these two series of 10 patients. There were 15 female and five male patients, with a median patient age of 18 years (IQR 17 to 23 years), a preoperative LCEA of 22° (IQR 18° to 24°), and a preoperative ACEA of 23° (IQR 18° to 27°). Exclusion criteria included missing preoperative CT or standard clinical radiographic imaging or severe joint incongruity. To address our first study question, digitally reconstructed radiographs matching each patient's standing AP and false-profile clinical radiographs were created from the segmented CT volumes. A board-certified orthopaedic surgeon and three trained researchers measured LCEA and ACEA on the digitally reconstructed radiographs, and the selected sourcil points were projected back into coordinates in the 3D anatomic space. To address our second study question, intraobserver and interobserver agreement in radiographic coverage angles were related to variations in 3D coordinates of the selected bony anatomy. Lastly, to address our third study question, 3D locations around the acetabular rim identified as contributing to the lateral and anterior sourcil points were summarized across patients in a clockface coordinate system, and statistical analysis of the "time" separating the 3D acetabular contributions of the sourcil edges was performed.

RESULTS

The 3D anatomy contributing to the lateral sourcil was a variable length (27 mm [IQR 15 to 34 mm]) span of the laterosuperior acetabular edges, with contributions by the anterior inferior iliac spine in 35% (7 of 20) of hips. The anterior sourcil reflected a 28-mm (IQR 25 to 31 mm) span of bone from the medial ilium (posterior-medial to the anterior-inferior iliac spine and anterior-lateral to the arcuate line) to the anterior and lateral edges of the acetabulum. Interobserver variability was good for LCEA (intraclass correlation coefficient [ICC] 0.82 to 0.83) and moderate to good for ACEA (ICC 0.73 to 0.79), whereas the agreement in identified 3D sourcil locations varied widely (ICC 0.32 to 0.95). The acetabular edge of the 3D anatomy contributing to the anterior sourcil overlapped the circumferential range of the acetabular rim contributing to the lateral sourcil.

CONCLUSION

Projection of two-dimensional radiographic landmarks contributing to the diagnosis of structural hip deformity into 3D allowed for the identification of the overlapping bony anatomy contributing to radiographically visible anterior and lateral sourcil edges.

CLINICAL RELEVANCE

This work leveraging digitally reconstructed radiographs and 3D pelvis anatomy has found that bone outside the joint contributes to the radiographic appearance of the sourcil and may variably confound estimates of joint coverage. Furthermore, the substantial overlap between the acetabular bone contributing to measurement of the LCEA and ACEA would indicate that these angles measure similar acetabular deformity, and that additional measures are needed to assess anterior coverage independent of lateral coverage.

The Otto Aufranc Award: Does Hip Arthroscopy at the Time of Periacetabular Osteotomy Improve the Clinical Outcome for the Treatment of Hip Dysplasia? A Multicenter Randomized Clinical Trial

BACKGROUND

A periacetabular osteotomy (PAO) is often sufficient to treat the symptoms and improve quality of life for symptomatic hip dysplasia. However, acetabular cartilage and labral pathologies are very commonly present, and there is a lack of evidence examining the benefits of adjunct arthroscopy to treat these. The goal of this study was to compare the clinical outcome of patients undergoing PAO with and without arthroscopy, with the primary end point being the International Hip Outcome Tool-33 at 1 year.

METHODS

In a multicenter study, 203 patients who had symptomatic hip dysplasia were randomized: 97 patients undergoing an isolated PAO (mean age 27 years [range, 16 to 44]; mean body mass index of 25.1 [range, 18.3 to 37.2]; 86% women) and 91 patients undergoing PAO who had an arthroscopy (mean age 27 years [range, 16 to 49]; mean body mass index of 25.1 [17.5 to 25.1]; 90% women).

RESULTS

At a mean follow-up of 2.3 years (range, 1 to 5), all patients exhibited improvements in their functional score, with no significant differences between PAO plus arthroscopy versus PAO alone at 12 months postsurgery on all scores: preoperative International Hip Outcome Tool-33 score of 31.2 (standard deviation [SD] 16.0) versus 36.4 (SD 15.9), and 12 months postoperative score of 72.4 (SD 23.4) versus 73.7 (SD 22.6). The preoperative Hip disability and Osteoarthritis Outcome pain score was 60.3 (SD 19.6) versus 66.1 (SD 20.0) and 12 months postoperative 88.2 (SD 15.8) versus 88.4 (SD 18.3). The mean preoperative physical health Patient-Reported Outcomes Measurement Information System score was 42.5 (SD 8.0) versus 44.2 (SD 8.8) and 12 months postoperative 48.7 (SD 8.5) versus 52.0 (SD 10.6). There were 4 patients with PAO without arthroscopy who required an arthroscopy later to resolve persistent symptoms, and 1 patient from the PAO plus arthroscopy group required an additional arthroscopy.

CONCLUSIONS

This randomized controlled trial has failed to show any significant clinical benefit in performing hip arthroscopy at the time of the PAO at 1-year follow-up. Longer follow-up will be required to determine if hip arthroscopy provides added value to a PAO for symptomatic hip dysplasia.

Patients With Dysplasia Achieve Similar Outcomes and Survivorship to Nondysplastic Patients 10 Years After Hip Arthroscopy for Femoroacetabular Impingement

PURPOSE

To determine the long-term outcomes of hip arthroscopy (HA) for femoroacetabular impingement (FAI) in the presence of concomitant lateral rim dysplasia compared with a matched control group.

METHODS

Patients undergoing HA between January 2009 and October 2013 with minimum 10-year follow-up were reviewed. The inclusion criteria consisted of patients undergoing HA for FAI with evidence of lateral rim dysplasia (lateral-center edge angle [LCEA] < 25°). Patients with lateral rim dysplasia were matched to patients with an LCEA greater than 30° based on sex, Tönnis grade, and age. Outcomes included survival (avoidance of total hip replacement [THR]), repeated HA, and patient-reported outcomes (PROs). Survivorship was assessed using a Kaplan-Meier curve and log rank test, whereas revision rates between groups were assessed using χ2 analysis. Between- and within-group analyses of PROs were conducted using the Mann-Whitney U test and Wilcoxon signed rank test, respectively. The proportion of cases achieving the patient acceptable symptom state was compared between groups using χ2 analysis.

RESULTS

This study comprised 46 dysplasia cases and 90 control cases. There was no statistically significant difference between groups in baseline metrics apart from the LCEA (P < .001), Sharp angle (P < .001), and Tönnis angle (P < .001). By 10 years postoperatively, 9% of dysplasia cases and 4% of control cases underwent conversion to THR. There was no statistically significant difference between groups in survival or revision rates. Both groups reported improvements in PROs, and there was no difference between PRO scores at either time point. Excluding cases that underwent THR, 84% and 83% of dysplasia and control cases, respectively, achieved the patient acceptable symptom state.

CONCLUSIONS

HA for symptomatic FAI is a successful treatment in cases in which dysplasia is present. Low complication rates, comparable outcomes to cases without lateral rim dysplasia, and a high survivorship rate of 91% at minimum 10-year follow-up are observed. Increasing Tönnis angle preoperatively may increase the risk of THR conversion.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Editorial Commentary: Decreased Hip Ligament Thickness in Patients With Dysplasia May Contribute to Hip Instability, Above and Beyond Associated Acetabular Under-coverage

Hip dysplasia is a pathomorphologic deformity that leads to decreased acetabular coverage and hip instability. Many different radiographic measurements have been explored to characterize hip dysplasia, including the lateral center-edge angle, femoral-epiphyseal acetabular roof index, and Tönnis angle. Magnetic resonance imaging offers 3-dimensional characterization of the hip pathomorphology that may be more detailed than 2-dimensional radiographs, as well as a modality that is free of radiation. Recent research has shown that dysplastic hips are associated with significantly thinner ligament thickness compared with non-dysplastic hips. The iliofemoral ligament is the most important hip capsular structure and helps to stabilize the hip joint, particularly in hip extension and external rotation. Differences in iliofemoral ligament thickness may help to explain why patients with dysplasia are more prone to hip instability, above and beyond their acetabular under-coverage. This reiterates the need for routine capsular closure and/or plication in patients with femoroacetabular impingement syndrome to prevent further instability.

The Iliopsoas: Anatomy, Clinical Evaluation, and Its Role in Hip Pain in the Athlete: A Scoping Review

Disability due to iliopsoas (IP) pain and dysfunction is underdiagnosed in the athletic population. The IP unit consists of the psoas major and iliacus muscles converging to form the IP tendon and is responsible primarily for hip flexion strength but has a number of secondary contributions such as femoral movement, trunk rotation, core stabilization, and dynamic anterior stability to the hip joint. As the IP passes in front of the anterior acetabulum and labrum, the diagnosis of IP pain may be confused with labral tearing seen on magnetic resonance imaging. This is in addition to the low sensitivity of magnetic resonance imaging to detect IP tendinitis and bursitis. Resisted seated hip flexion as well as direct palpation of the IP tendon and muscle belly are useful to assess function and help determine whether the IP may be the source of pain, which is common in athletes. Both biomechanical and clinical investigations have demonstrated the role of IP as an anterior hip stabilizer. Patients with signs of hip microinstability, developmental dysplasia of the hip, and increased femoral anteversion are at risk of IP pain and poor outcomes after IP lengthening, highlighting the importance of the IP in providing dynamic anterior hip stability.

Editorial Commentary: Revision Hip Arthroscopy in Patients With Borderline Dysplasia Has a Role: Indications Are Narrow Versus Periacetabular Osteotomy

Hip arthroscopy (HA) is preferred for surgical management of femoroacetabular impingement syndrome, whereas periacetabular osteotomy (PAO) is the gold standard for frank developmental hip dysplasia in young adults. Borderline hip dysplasia (BHD) is a conundrum, with data supporting the use of either or both, not to mention that BHD is defined by varying lateral center-edge angle thresholds between 18° and 25° or 20° and 25° and features generalized ligamentous laxity and variations in acetabular and femoral version. That said, HA for BDH has been shown to have 10-year survivorship of 82%. In a revision situation after HA in patients with BHD, PAO seems a logical next step, but HA may be indicated under narrow indications. From a technical standpoint, capsular preservation, labral function restoration, and avoiding acetabular rim over-resection are key points when performing HA in BHD. Most important, particularly in the revision setting, is to determine the root cause of failure. Primarily, instability-driven symptoms are an indication for PAO.

Noninterportal capsulotomy of hip arthroscopy showed improved outcomes in borderline hip dysplasia: A retrospective study with minimum 2-year follow-up

PURPOSE

The present study aimed to evaluate the functional outcomes of hip arthroscopy using a noninterportal capsulotomy technique to address labral tears in patients with borderline hip dysplasia (BHD). Additionally, we also compared these outcomes with those of patients with BHD who underwent the standard repaired interportal capsulotomy (RIPC) arthroscopy.

METHODS

Data from patients with BHD were retrieved from a database of patients who underwent arthroscopic hip surgery with noninterportal capsulotomy or RIPC to treat labral tears between January 2014 and December 2020. Data collected included both pre- and postoperative patient-reported outcomes (PROs).

RESULTS

A total of 58 patients (noninterportal capsulotomy, n = 37; RIPC, n = 21) with a mean age of 30.9 ± 5.6 and 28.6 ± 5.5 years, respectively, met the inclusion criteria. All of the patients underwent a minimal 2-year follow-up. The mean lateral centre-edge angle was 23.3 ± 1.2° in the noninterportal capsulotomy group and 23.7 ± 1.0° in the RIPC group, with no significant difference. The PROs improved from the preoperative to the latest follow-up, with a p < 0.001. There were no differences between the groups.

CONCLUSION

Using strict patient selection criteria, hip arthroscopy with noninterportal capsulotomy demonstrated significant pre- to postoperative improvements in patients with BHD and achieved results comparable to those from hip arthroscopy with RIPC.

LEVEL OF EVIDENCE

Level III.

Primary and Revision Hip Arthroscopy in Borderline Hip Dysplasia Shows Comparable Outcomes at a Minimum 5-Year Follow-Up

PURPOSE

To compare patient-reported outcomes (PROs), achievement of clinically significant outcomes, and reoperation-free survivorship between primary and revision hip arthroscopy (HA) for femoroacetabular impingement syndrome (FAIS) in propensity-matched borderline hip dysplasia (BHD) patients at a minimum 5-year follow-up.

METHODS

Patients with BHD, characterized by a lateral center-edge angle 18° to 25°, who underwent HA for FAIS with capsular repair by a single surgeon between January 2012 and June 2018 with a minimum 5-year follow-up were identified. Cases of revision HA were propensity-matched 1:2 to cases of primary HA, controlling for age, sex, and body mass index. A 1:2 ratio was chosen to maximize the number of included patients. Collected PROs included Hip Outcome Score-Activities of Daily Living and Sport Subscales, International Hip Outcome Score 12, modified Harris Hip Score, and Visual Analog Scale for Pain. Achievement of minimal clinically important difference, patient acceptable symptom state, and substantial clinical benefit for any measured PRO was compared between groups along with reoperation-free survivorship using Kaplan-Meier analysis.

RESULTS

Thirty-six revision HA hips (34 patients) were propensity-matched to 72 primary HA hips (70 patients). The groups were similar in age (31.5 ± 10.3 years vs 30.5 ± 11.2, P = .669), sex (69.4% female vs 70.8%, P = .656), and body mass index (25.7 ± 4.0 vs 25.5 ± 3.7, P = .849). The revision group showed a greater prevalence of prolonged preoperative pain (50.0% vs 27.8%, P = .032) compared with the primary group. A significant improvement in all PROs was observed for both groups with comparable PROs preoperatively and at the 5-year follow-up between groups (P ≥ .086). The revision and primary groups showed comparable minimal clinically important difference (95.0% vs 95.7%, P ≥ .999), patient acceptable symptom state (80.0% vs 83.6%, P = .757), and substantial clinical benefit (62.5% vs 70.7%, P = .603) achievement for any PRO. Comparable reoperation-free survivorship was observed (P = .151).

CONCLUSIONS

Propensity-matched patients with BHD undergoing primary and revision hip arthroscopy for FAIS achieved similar minimum 5-year PROs, clinically significant outcomes, and reoperation-free survivorship.

LEVEL OF EVIDENCE

Level III, retrospective comparative case series.

Outcomes of Flexibility Sport Athletes With Borderline Hip Dysplasia After Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Propensity-Matched Analysis at Minimum 2-Year Follow-up

BACKGROUND

Hip arthroscopy has proved successful in treating femoroacetabular impingement syndrome (FAIS) in patients with and without borderline hip dysplasia (BHD). Despite a high prevalence of BHD in patients who participate in sports with high flexibility requirements, a paucity of literature evaluates the efficacy of hip arthroscopy in treating FAIS in flexibility sport athletes with BHD.

PURPOSE

To compare minimum 2-year patient-reported outcomes (PROs) and achievement of clinically significant outcomes in flexibility sport athletes with BHD undergoing primary hip arthroscopy for FAIS with capsular plication with results in flexibility sport athletes without dysplasia.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected for patients undergoing primary hip arthroscopy for FAIS with BHD, defined as a lateral center-edge angle of 18° to 25°, who reported participation in a sport with a high flexibility requirement, including dance, gymnastics, figure skating, yoga, cheerleading, and martial arts, according to previous literature. These patients were matched 1:2 to flexibility sport athletes without dysplasia, controlling for age, sex, and body mass index. Preoperative and minimum 2-year postoperative PROs were collected and compared between groups. Cohort-specific minimal clinically important difference and patient acceptable symptom state achievement was compared between groups.

RESULTS

In total, 52 flexibility sport athletes with BHD were matched to 104 flexibility sport athletes without BHD. Both groups showed similar sport participation (P = .874) and a similar level of competition (P = .877). Preoperative lateral center-edge angle (22.2°± 1.6° vs 31.5°± 3.9°; P < .001) and Tönnis angle (10.9°± 3.7° vs 5.8°± 4.4°; P < .001) differed between groups. Capsular plication was performed in all cases. Both groups achieved significant improvement in all PROs (P < .001) with no differences in postoperative PROs between groups (P≥ .147). High minimal clinically important difference (BHD group: 95.7%; control group: 94.8%) and patient acceptable symptom state (BHD group: 71.7%; control group: 72.2%) achievement for any PRO was observed with no differences between groups (P≥ .835).

CONCLUSION

Flexibility sport athletes with BHD achieved similar outcomes as those of flexibility sport athletes without BHD after hip arthroscopy for FAIS with capsular plication.

Borderline Hip Dysplasia Is Not Associated With Significant Differences in Hip Survivorship or Patient-Reported Outcomes Following Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Propensity-Matched Cohort Study

PURPOSE

To compare hip survivorship and patient-reported outcomes after primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS) in patients with versus without comorbid borderline hip dysplasia (BHD) at 2-year follow-up.

METHODS

A retrospective matched-cohort study was conducted involving patients who underwent primary hip arthroscopy for FAIS with a single surgeon from 2010 to 2019. BHD was defined as lateral center edge angle (LCEA) of 20 to 25°. Subjects with BHD were matched 1:2 to controls without BHD on age, sex, body mass index, and preoperative modified Harris Hip Score (mHHS). Alpha angle, LCEA, Tönnis angle, and acetabular retroversion signs were measured on preoperative and/or postoperative hip radiographs. Patient-reported outcomes were assessed using the mHHS and the Non-Arthritic Hip Score. Hip survivorship, outcome scores, and achievement of the minimum clinically important difference were compared between groups using the Mann-Whitney U test or Fisher exact test, as appropriate. P values <.05 were considered significant.

RESULTS

Thirty-one BHD subjects (mean age 36.8 years, 71.0% female) and 62 controls (mean age 38.0 years, 71.0% female) were included. There were no significant intergroup differences in demographics or preoperative radiographic measurements besides LCEA and Tönnis angle (all P > .05). Intraoperatively, subjects with BHD were found to have significantly shorter labral tears (mean 2.6 vs 2.8 clock-face hours, P = .048), but there were no significant intergroup differences in acetabular or femoral cartilage status (all P > .05). Postoperatively, there were no significant intergroup differences in rates of revision arthroscopy (BHD 6.5% vs control 11.3%) or conversion to total hip arthroplasty (BHD 9.7% vs control 1.6%), in 2-year improvement of the mHHS and Non-Arthritic Hip Score, or in minimum clinically important difference achievement rates (all P > .05).

CONCLUSIONS

BHD is not associated with a significant difference in hip survivorship or patient-reported outcomes following primary hip arthroscopy for FAIS.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Predicting Outcomes in Hip Arthroscopy for Femoroacetabular Impingement Syndrome

PURPOSE OF REVIEW

Arthroscopic treatment of femoroacetabular impingement syndrome (FAIS) continues to rise in incidence, and thus there is an increased focus on factors that predict patient outcomes. The factors that impact the outcomes of arthroscopic FAIS treatment are complex. The purpose of this review is to outline the current literature concerning predictors of patient outcomes for arthroscopic treatment of FAIS.

RECENT FINDINGS

Multiple studies have shown that various patient demographics, joint parameters, and surgical techniques are all correlated with postoperative outcomes after arthroscopic FAIS surgery, as measured by both validated patient-reported outcome (PRO) scores and rates of revision surgery including hip arthroplasty. To accurately predict patient outcomes for arthroscopic FAIS surgery, consideration should be directed toward preoperative patient-specific factors and intraoperative technical factors. The future of accurately selecting patient predictors for outcomes will only improve with increased data, improved techniques, and technological advancement.

Editorial Commentary: Arthroscopy With Labral Preservation or Reconstruction Plus Capsular Closure Shows Excellent Outcome in Patients With Borderline Hip Dysplasia and is Less Invasive Than Periacetabular Osteotomy

Borderline developmental dysplasia of the hip (BDDH), or borderline hip dysplasia (BHD), traditionally characterized by a relatively low lateral center-edge angle (LCEA), presents a complex challenge in treatment due to its multifaceted etiology involving instability, femoroacetabular impingement (FAI), or a combination thereof. The optimal approach to managing adult BDDH remains a subject of significant debate. Periacetabular osteotomy (PAO) is considered the preferred treatment for addressing severe acetabular under-coverage, as it rectifies the underlying bony deficiency and promotes stability. However, the treatment of BDDH is less straightforward, particularly with the advancement of hip arthroscopy techniques, specifically labral preservation and capsular management. Given the minimally invasive and rapid postoperative rehabilitation advantage for arthroscopic procedures over open surgeries, numerous attempts have been undertaken in this context. Research has revealed favorable patient-reported outcomes (PROs), low failure rates, and a significant proportion of returning to sports (RTS) after arthroscopic management for patients with BDDH. Although we might in the right direction, Level I evidence studies are needed to comprehensively compare long-term PROs, failure rates, and rates of RTS between arthroscopy and PAO in the treatment of BDDH.

Osteochondral Allograft or Autograft Transplantation of the Femoral Head Leads to Improvement in Outcomes but Variable Survivorship: A Systematic Review

PURPOSE

To review patient-reported outcomes (PROs) and survivorship in patients undergoing osteochondral autograft or allograft transplantation (OAT) of the femoral head.

METHODS

PubMed, Cochrane Center for Register of Controlled Trials, and Scopus databases were searched in November 2022 with an updated search extending to December 2023 using criteria from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the following keywords: (hip OR femoral head) AND (mosaicplasty OR osteochondral allograft OR osteochondral autograft OR osteochondral lesion). Articles were included if they evaluated postoperative PROs in patients who underwent OAT of the femoral head and had a study size of 5 or more hips (n ≥ 5). Survivorship was defined as freedom from conversion to total hip arthroplasty. For PROs evaluated in 3 studies or more, forest plots were created and I2 was calculated.

RESULTS

Twelve studies were included in this review, with a total of 156 hips and a mean follow-up time ranging between 16.8 and 222 months. In total, 104 (66.7%) hips were male while 52 (33.3%) were female. Age of patients ranged from 17.0 to 35.4 years, while body mass index ranged from 23.3 to 28.1. Eight studies reported on osteochondral autograft transplantation and 4 studies on osteochondral allograft transplantation. Three studies reported significant improvement in at least 1 PRO. Survivorship ranged from 61.5% to 96% at minimum 2-year follow-up and from 57.1% to 91% at minimum 5-year follow-up. At a follow-up of less than 5 years, osteochondral allograft transplantation studies showed 70% to 87.5% survivorship, while autograft varied from 61.54% to 96%.

CONCLUSIONS

Patients with osteochondral lesions of the femoral head who underwent osteochondral autograft or allograft transplantation demonstrated improved PROs but variable survivorship rates.

LEVEL OF EVIDENCE

Level IV, systematic review of Level IV studies.

Hip Arthroscopic Surgery With Chondrolabral Refixation, Osteochondroplasty, and Routine Capsular Closure for Femoroacetabular Impingement Syndrome: Clinical Outcomes at a Minimum 10-Year Follow-up

BACKGROUND

Hip arthroscopic surgery for femoroacetabular impingement syndrome (FAIS) has proven to be an effective surgical intervention, with high rates of return to sport and work as well as favorable outcomes at short- and midterm follow-up. However, limited data exist on outcomes at long-term follow-up.

PURPOSE

To evaluate patient-reported outcomes (PROs) at a minimum 10-year follow-up after primary hip arthroscopic surgery including labral repair, femoral osteochondroplasty, acetabular osteochondroplasty, and capsular closure for FAIS.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent primary hip arthroscopic surgery for FAIS between June 2012 and January 2013 were identified. PROs were collected preoperatively and at a minimum of 10 years postoperatively, including the Hip Outcome Score-Activities of Daily Living (HOS-ADL), Hip Outcome Score-Sports Subscale (HOS-SS), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (iHOT-12), and visual analog scale (VAS) for pain and satisfaction. Unique minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) thresholds were calculated, and their rates of achievement were analyzed. An alpha level of <.05 was used to determine statistical significance.

RESULTS

A total of 94 patients (55 female; mean age, 34.3 ± 12.4 years) were analyzed with a mean follow-up of 10.1 ± 0.3 years (range, 10.0-10.7 years). Patients demonstrated significant 10-year improvement across all PRO measures (P < .001). MCID and PASS thresholds were calculated as follows: HOS-ADL (10.4 and 85.3, respectively), HOS-SS (14.6 and 60.2, respectively), mHHS (8.8 and 76.0, respectively), VAS pain (14.6 and 27.5, respectively), and iHOT-12 (PASS: 71.4). The majority of patients achieved the MCID and PASS for each PRO measure: HOS-ADL (73.4% and 70.9%, respectively), HOS-SS (78.5% and 77.2%, respectively), mHHS (81.0% and 70.9%, respectively), VAS pain (88.6% and 70.9%, respectively), and iHOT-12 (PASS: 73.4%). Overall, 9 patients (9.6%) underwent subsequent revision hip arthroscopic surgery at a mean 4.9 ± 3.7 years (range, 1.1-10.1 years) postoperatively, and 6 patients (6.4%) underwent conversion to total hip arthroplasty at a mean 4.1 ± 3.1 years (range, 0.9-9.3 years) postoperatively.

CONCLUSION

Patients who underwent primary hip arthroscopic surgery for FAIS utilizing contemporary methods of labral repair, acetabular and/or femoral osteochondroplasty, and capsular closure commonly experienced sustained clinical improvement and reported high levels of satisfaction at a minimum 10-year follow-up with low rates of reoperation.

Editorial Commentary: Hip Arthroscopy Outcomes May Have a Gender Bias

It is a great challenge to analyze whether sex difference affects outcome of hip arthroscopy, because the indications, risk factors, and comorbidities are difficult to determine and may be heterogeneous between and within studies. For instance, mental health disorders, namely depression, are associated with worse outcomes following hip arthroscopy, and these disorders tend to be more prevalent in a female population. There are also known bony morphologic differences between men and women. Women tend to have a higher rate of borderline hip dysplasia defined by lateral center-edge angle between 18 and 25°. This is notable because long-term (10 year) survivorship of patients with this morphology undergoing hip arthroscopy is notably lower (79-82.2%) compared with patients undergoing hip arthroscopy without BHD (>90%). These gender differences, although notable within specific cohorts, are more difficult to tease out in large systematic reviews with all comers. In addition, many studies do not have longer-term follow-up required to assess conversion to THA. Perhaps hip arthroscopy outcomes are instead directly linked to independent bony morphologic, psychologic, and soft tissue-based risk factors that may have a gender bias.