Hip Arthroscopy and Borderline Developmental Dysplasia of the Hip: A Systematic Review

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.

How useful are indirect radiographic measurements of hip instability in borderline hip dysplasia? An MRI-based comparison to a healthy cohort

PURPOSE

Symptomatic hips with borderline hip dysplasia (BHD) morphology pose a challenge in differentiating stable from unstable hips. The current study aims to compare indirect radiographic signs of instability in a symptomatic BHD population to those in a healthy cohort.

METHODS

The study group consisted of patients with a lateral centre-edge angle (LCEA) with values 18° ≤ LCEA < 25° who underwent corrective periacetabular osteotomy (PAO) and reported an improvement in patient-reported outcome measures (PROMs). The comparison group consisted of a healthy cohort of athletes who did not complain of any hip-related symptoms and who had normal values of their hip morphological parameters (LCEA, acetabular index (AI°), alpha angle (α°), femoral version, acetabular version). Indirect signs of instability consisting of the femoro-epiphyseal acetabular roof index (FEAR), iliocapsularis-to-rectus-femoris (IC/RF) ratio and labral dimensions (height-to-length ratio) were assessed in both groups. Partial Pearson correlation, logistic multiple regression analysis and Receiver-Operating Characteristic (ROC) curve analysis were performed to determine correlations, as well as the sensitivity and specificity of these signs to differentiate between healthy hips and BHD.

RESULTS

On binary logistic multiple regression analysis, the FEAR Index was the only independent predictor to differentiate between BHD and healthy hips (p < 0.001). The IC/RF ratio did not achieve significance. The calculated area under the curve (AUC) was 0.93 (0.87 - 0.99, CI 95%, p < 0.001) for the FEAR Index and 0.81 (0.70 - 0.92, CI 95%, p < 0.001) for the height-length ratio. Using the predefined cut-off values (dysplastic-FEAR Index ≥ 5° or labral height-to-length ratio ≤ 0.5), 27% sensitivity/100% specificity and 20% sensitivity/ 100% specificity, were achieved. ROC analysis provided the following new thresholds: FEAR Index ≥ -5° (73% sensitivity/97% specificity); labral height-to-length ratio ≤ 0.8 (70% sensitivity, 79% specificity).

CONCLUSION

In our cohort, the FEAR index was an independent parameter that could differentiate between borderline dysplastic and asymptomatic hips. The previously published values for both the FEAR index and labral hypertrophy ratio had a poor sensitivity in differentiating symptomatic unstable BHD from healthy hips. The cut-off values of ≥ -5° (FEAR index) and ≤ 0.8 (labral height-to-length ratio) provided acceptable sensitivity and specificity when comparing to morphological healthy hips.

Femoro-Epiphyseal Acetabular Roof Index Values on Anteroposterior Pelvic Radiographs Significantly Increase With Hip Adduction and Decrease With Abduction

PURPOSE

To investigate the impact of hip adduction and abduction on the femoro-epiphyseal acetabular roof (FEAR) index using conventional anteroposterior pelvic radiographs of patients with borderline hip dysplasia (BHD).

METHODS

Patients with BHD (lateral center edge angle [LCEA] with values of 18° ≤ LCEA <25°) and who were subject to periacetabular osteotoym were selected from a consecutive retrospective cohort from January 2009 to January 2016. The hip ad-/abduction (adduction handled as negative values) and the FEAR index (lateral opening angles handled as positive values) were measured in the initially standardized acquired pelvic radiographs. Thereafter, using surgical planning software, different degrees of hip adduction and abduction were simulated from 20° of adduction to 30° of abduction, and the FEAR index was measured at each position. Pearson correlation was used to identify a potential correlation between the hip ad-/abduction and the FEAR index.

RESULTS

Eighty-nine hips were included. Initial radiographs showed unintentional mean ad-/abduction of -5.3° ± 3.1° (range, -14° to 2°). The mean FEAR index at the initial ad-/abduction angle was -3.6° ± 7.2° (range, -18.0° to 16.0°) and was significantly different from neutral position (0° of ad-/abduction) -9.2° ± 7.0° (range, -27.0° to 10.0°) (P < .001). The FEAR index was negatively correlated to the hip ad-/abduction angle (r = 1, P < .001), with lower values for the FEAR index with the hip in abduction.

CONCLUSIONS

Significant differences in FEAR index measurements were observed depending on hip ad-/abduction on pelvic radiographs. A linear change of the FEAR index of 5° per 5° of hip adduction or abduction could be demonstrated, with adduction resulting in increasing and abduction in decreasing values for the FEAR index.

LEVEL OF EVIDENCE

Level III, diagnostic study.

Primary Hip Arthroscopy in Patients With Acetabular Dysplasia: A Systematic Review of Published Clinical Outcomes at Minimum 5-Year Follow-up

BACKGROUND

Hip arthroscopy in patients with borderline hip dysplasia has satisfactory outcomes at short-term follow-up; however, the data on midterm outcomes are inconsistent, and failure rates are high in some studies, limiting understanding of the role and utility of hip arthroscopy in this patient cohort.

PURPOSE

To provide an up-to-date, evidence-based review of the clinical outcomes of primary hip arthroscopy in patients with frank or borderline hip dysplasia at ≥5-year follow-up and report the failure rate and progression to total hip arthroplasty in this cohort.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they evaluated outcomes of primary hip arthroscopy in patients with lateral center-edge angle (LCEA) <25° at ≥5-year follow-up. Risk of bias assessment was performed using the methodological index for non-randomized studies scoring system. Level of evidence was determined using criteria from the Oxford Centre for Evidence-Based Medicine.

RESULTS

Nine studies were included in this review. Patients with LCEA <25° demonstrated satisfactory clinical outcomes, high patient satisfaction, and significant postoperative improvements in patient-reported outcomes (PROs) at follow-up ranging from a ≥5 to 10 years. Studies comparing patients with dysplasia to those without did not demonstrate significant differences in preoperative, postoperative, or delta PROs or in failure, reoperation, or revision rates. There was no overall significant correlation between outcomes and LCEA stratification.

CONCLUSION

Hip arthroscopy in carefully selected patients with LCEA <25° can be successful at mid- to long-term follow-up and may provide clinical outcomes and failure rates comparable with patients with normal LCEA, understanding that this is a singular, 2-dimensional radiographic measure that does not differentiate instability from impingement or combinations thereof, warranting future studies delineating these differences. These findings suggest that hip dysplasia may not be an absolute contraindication for isolated hip arthroscopy and may serve as a viable intervention with consideration of staged future periacetabular osteotomy (PAO). Importantly, this review does not suggest that hip arthroscopy alters the natural history of dysplasia; therefore, patients with dysplasia should be counseled on the potential utility of PAO by appropriate hip preservation specialists.

Bibliometric analysis of the acetabular labrum

The acetabular labrum (AL) plays a crucial role in the normal physiological functioning of the hip joint. This study aims to present an overview of the current status and research hotspots concerning the AL and to explore the field from a bibliometric perspective. A total of 1918 AL-related records published between January 1, 2000 and November 8, 2023 were gathered from the Web of Science Core Collection database. By utilizing tools such as HisCite, CiteSpace, VOSviewer, and the R package "bibliometrix," the regions, institutions, journals, authors, and keywords were analyzed to predict the latest trends in AL research. Global research interest and publication output related to this topic continues to escalate. The United States leads in international collaborations, number of publications, and citation frequency, underscoring its preeminent position in this field. The American Hip Institute emerged as the most prolific institution, making the greatest contribution to publications. Notably, Arthroscopy and the American Journal of Sports Medicine are the 2 most popular journals in this domain, accounting for 13.29% and 10.1% of publications, respectively, and were also found to be the most co-cited journals. Amongst authors, Benjamin G. Domb leads with 160 articles (8.35%), while Marc J. Philippon is the most frequently cited author. The keyword co-occurrence network showed 3 hot clusters, including "AL," "femoral acetabular impingement (FAI)," and "osteoarthritis." In addition, "survivorship," "FAI," and "patient-reported outcomes" were identified as trending topics for future exploration. This study represents the first comprehensive bibliometric analysis, summarizing the present state and future trends in AL research. The findings serve as a valuable resource for scholars, offering practical insights into key information within the field and identifying potential research frontiers and emerging directions in the near future.

Outcome Scores and Survivorship of Patients Undergoing Primary Hip Arthroscopy With Borderline Hip Dysplasia: A Propensity-Matched Study With Minimum 10-Year Follow-up

BACKGROUND

Patients with borderline hip dysplasia (BHD) and concomitant femoroacetabular impingement syndrome (FAIS) have demonstrated similar outcomes at short- and midterm follow-up compared with equivalent patients without dysplasia. However, comparisons between these groups at long-term follow-up have yet to be investigated.

PURPOSE

To compare long-term clinical outcomes between patients with BHD undergoing primary hip arthroscopy for FAIS versus matched control patients without BHD.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A retrospective cohort study was conducted on patients with BHD (lateral center-edge angle, 18°-25°) who underwent hip arthroscopy for FAIS between January 2012 and February 2013. Patients were propensity matched in a 1:3 ratio by age, sex, and body mass index to control patients without BHD who underwent primary hip arthroscopy. Groups were compared in terms of patient-reported outcomes (PROs) preoperatively and at 10 years postoperatively, including the Hip Outcome Score Activities of Daily Living subscale (HOS-ADL) and Sports subscale (HOS-SS), modified Harris Hip Score, 12-item International Hip Outcome Tool, visual analog scale (VAS) for pain and satisfaction. Achievement rates for minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) were compared between groups. Kaplan-Meier survivorship curves were assessed between groups.

RESULTS

At a mean follow-up of 10.3 ± 0.3 years, 28 patients with BHD (20 women; age, 30.8 ± 10.8 years) were matched to 84 controls who underwent primary hip arthroscopy. Both groups significantly improved from preoperative assessment in all PRO measures at 10 years (P < .001 for all). PRO scores were similar between groups, aside from HOS-SS (BHD, 62.9 ± 31.9 vs controls, 80.1 ± 26.0; P = .030). Rates of MCID achievement were similar between groups for all PROs (HOS-ADL: BHD, 76.2% vs controls, 67.9%, P = .580; HOS-SS: BHD, 63.2% vs controls, 69.4%, P = .773; modified Harris Hip Score: BHD, 76.5% vs controls, 67.9%, P = .561; VAS pain: BHD, 75.0% vs controls, 91.7%, P = .110). Rates of PASS achievement were significantly lower in the BHD group for HOS-ADL (BHD, 39.1% vs controls, 77.4%; P = .002), HOS-SS (BHD, 45.5% vs controls, 84.7%; P = .001), and VAS pain (BHD, 50.0% vs controls, 78.5%; P = .015). No significant difference was found in the rate of subsequent reoperation on the index hip between groups. Kaplan-Meier survival analysis demonstrated comparable survivorship at long-term follow-up (P = .645).

CONCLUSION

After primary hip arthroscopy, patients with BHD in the setting of FAIS had significantly improved PRO scores at 10-year follow-up, comparable with propensity-matched controls without BHD. Rates of MCID achievement were similar between groups, although patients with BHD had lower rates of PASS achievement. Patients with BHD had similar long-term hip arthroscopy survivorship compared with controls, with no significant difference in rates of revision hip arthroscopy or conversion to total hip arthroplasty.

Hip Arthroscopy in Patients With Generalized Joint Hypermobility Yields Successful Outcomes: A Systematic Review

PURPOSE

To evaluate the outcomes of hip arthroscopy in patients with generalized joint hypermobility (GJH).

METHODS

A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses. An electronic record search was performed in PubMed, Web of Science, Cochrane Library, and Embase. A 2-stage title/abstract and full-text screening was performed using the following inclusion criteria: (1) observational studies, cohort studies, and randomized controlled trials; (2) describing more than 5 patients with a mean age over 18 years and GJH; (3) undergoing arthroscopy of the hip; (4) reporting patient-reported outcome measures (PROMs), return to sport, or complications/reoperations; and (5) published in English.

RESULTS

Of the 517 articles identified, 10 studies meeting all selection criteria were included. Included studies report significant improvements in a range of different functional and pain-based PROMs. Most patients (25.0%-97.0%) in each study achieved a clinically important improvement postoperatively in at least 1 PROM. No complications were described in any of the 4 studies reporting this metric. One study each found an association between GJH and an increased risk of postoperative deep gluteal syndrome and iliopsoas tendinitis. The rate of revision arthroscopy ranged from 0% to 11.4%, and only 2 patients in a single study of 11 hips required conversion to total hip arthroplasty. No statistically significant differences were reported between patients with and without GJH with respect to any of the described outcomes.

CONCLUSIONS

Patients with GJH may achieve good outcomes following hip arthroscopy with respect to PROMs, perioperative complications, reoperation, and return to sport. With effective labral repair and capsular closure, outcomes achieved in patients with GJH are comparable to those reported in patients without hypermobility.

LEVEL OF EVIDENCE

Level IV, systematic review of level III to IV studies.

No Difference in Patient-Reported Outcomes for Periacetabular Osteotomy and Hip Arthroscopy With Capsular Plication in the Setting of Borderline Hip Dysplasia: A Propensity-Matched Multicenter Study With Minimum 5-Year Follow-Up

PURPOSE

To compare minimum 5-year patient-reported outcome measures after hip arthroscopy (HA) and periacetabular osteotomy (PAO) for borderline hip dysplasia.

METHODS

Hips with a lateral center-edge angle (LCEA) between 18° and less than 25° that underwent either PAO or HA were selected from 2 institutions. The exclusion criteria were as follows: LCEA less than 18°, Tönnis osteoarthritis grade greater than 1, prior hip surgical procedures, active inflammatory disease, Workers' Compensation, and concomitant surgery. Patients underwent propensity matching based on age, sex, body mass index, and Tönnis osteoarthritis grade. Patient-reported outcome measures included the modified Harris Hip Score, as well as calculation of the minimal clinically important difference, patient acceptable symptom state, and maximum outcome improvement satisfaction threshold. Preoperative radiographic predictors included comparison of the Femoro-epiphyseal Acetabular Roof index and ligamentum teres lesions.

RESULTS

A total of 28 PAO patients underwent propensity matching to 49 HA patients. The 2 groups were similar in terms of mean age, sex, preoperative body mass index, and LCEA. The PAO group had a longer mean follow-up period (95.8 months vs 81.3 months, P = .001). The mean Femoro-epiphyseal Acetabular Roof index was significantly lower preoperatively in the HA group (P < .001). The 2 groups showed similar and significant improvements in the mean modified Harris Hip Score from preoperatively to latest follow-up (P < .001). The relative risk of subsequent surgery in the PAO group was 3.49 (P = .024), mostly attributed to hardware removal (25%). The revision rate was 3.6% in the PAO group and 8.2% in the HA group (P = .65). One patient in the PAO group required revision HA for intra-articular adhesions. Three of the patients requiring revision in the HA group underwent PAO because of persistent pain, and one underwent revision HA alone. Conversion to total hip arthroplasty was required in 1 patient in the HA group and no patients in the PAO group.

CONCLUSIONS

Both PAO and HA with capsular plication provide borderline hip dysplasia patients with clinically significant improvements and low revision rates at a minimum of 5 years postoperatively.

LEVEL OF EVIDENCE

Level III, retrospective, comparative therapeutic trial.

Physical Therapy May Not Be Successful for Patients With Cam-Type Femoroacetabular Impingement Syndrome and May Result in Insufficient Hip Range of Motion When Femoral Anteversion Is Less Than 16° and α-Angle Is Greater Than 65°

PURPOSE

To identify factors associated with insufficient range of motion (ROM) improvement after the posterior pelvic tilt change in cam-type femoroacetabular impingement syndrome.

METHODS

Preoperative computed tomography images from 71 consecutive patients with femoroacetabular impingement syndrome treated with arthroscopic cam resection were evaluated. Using a dynamic computer simulation program, 3-dimensional models with a 10° posterior pelvic tilt from the supine functional pelvic plane (baseline) were created by computed tomography models. Patients were divided into 2 groups: those who experienced >10° (effective group) and ≤10° (ineffective group) improvements in internal rotation at 90° flexion after a 10° posterior pelvic tilt. Demographic characteristics; preoperative range of internal rotation at 90° flexion; and radiographic parameters, including Tönnis grade, lateral center-edge angle, acetabular roof obliquity angle, central acetabular anteversion, cranial acetabular anteversion, femoral anteversion, and α angle, were compared in the 2 groups. Univariate and multivariable logistic regression analyses were performed to evaluate factors associated with insufficient ROM improvement following a 10° posterior pelvic tilt.

RESULTS

The 71 patients included 58 men and 13 women, of mean age 41.4 ± 14.6 years. Posterior pelvic tilt was effective in 13 hips and ineffective in 58. Univariate analysis showed that preoperative range of internal rotation at 90°flexion, femoral anteversion, and α angle differed significantly in the 2 groups. Multivariable analysis showed that femoral anteversion <16° (odds ratio 7.4; 95% confidence interval 1.6-35; P = .012) and α angle >65° (odds ratio 6.7; 95% confidence interval 1.2-37; P = .027) were significant factors associated with insufficient ROM improvement after posterior pelvic tilt.

CONCLUSIONS

Physical therapy may not be successful for patients with cam-type femoroacetabular impingement syndrome and may result in insufficient hip ROM when femoral anteversion is less than 16° and α-angle is greater than 65°.

CLINICAL RELEVANCE

Patients with a prominent cam-type deformity and lower anterior femoral anteversion are at high risk of clinical failure following improvement in pelvic mobility by conservative treatment alone and are likely to benefit from surgery for cam deformity.

Improved Functional Outcomes of Combined Hip Arthroscopy and Periacetabular Osteotomy at Minimum 2-Year Follow-Up

PURPOSE

To evaluate patient-reported outcomes (PROs) and survivorship at minimum 2-year follow-up after combined hip arthroscopy and periacetabular osteotomy (PAO) performed in the setting of a single anesthetic event.

METHODS

Patients who underwent combined hip arthroscopy (M.J.P.) and PAO (J.M.M.) between January 2017 and June 2020 were identified. Preoperative and minimum 2-year postoperative PROs including Hip Outcome Score-Activities of Daily Living (HOS-ADL), HOS-Sport, modified Harris Hip Score (mHHS), Western Ontario and McMaster Universities Osteoarthritis Index, 12-Item Short Form Survey Mental Component Scores (SF-12 MCS), and 12-Item Short Form Survey Physical Component Score were collected and compared in addition to revision rate, conversion to total hip arthroplasty (THA), and patient satisfaction.

RESULTS

Twenty-four of 29 patients (83%) eligible for the study were available for 2-year minimum follow-up with a median follow-up time of 2.5 years (range, 2.0-5.0). There were 19 females and 5 males with mean age of 31 ± 12 years. Mean preoperative lateral center edge angle was 20° ± 5° and alpha angle was 71° ± 11°. One patient underwent reoperation for removal of a symptomatic iliac crest screw at 11.7 months after operation. Two patients, a 33-year-old woman and a 37-year-old man, were converted to THA at 2.6 and 1.3 years, respectively, following the combined procedure. Both patients had a Tönnis grade of 1 on radiographs, as well as bipolar Outerbridge grade III/IV defects requiring microfracture of the acetabulum. For patients who did not convert to THA (n = 22), there was significant improvement from before to after surgery for all scores (P < .05) except SF-12 MCS. The minimal clinically significant difference and patient-acceptable symptom state rates for HOS-ADL, HOS-Sport, and mHHS were 72%, 82%, 86%, and 95%, 91%, and 95%, respectively. Median patient satisfaction was 10 (range, 4 to 10).

CONCLUSIONS

Single-stage combined hip arthroscopy with periacetabular osteotomy for patients with symptomatic hip dysplasia results in improvement in PROs and arthroplasty free survivorship of 92% at median 2.5 year follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Femoral Anteversion Is Associated With a Thinner Anterior Capsule in Patients With Femoroacetabular Impingement Syndrome

PURPOSE

To measure femoral torsion on computed tomography images in patients with femoroacetabular impingement syndrome and explore whether femoral torsion was significantly correlated with anterior capsular thickness.

METHODS

Prospectively collected data of surgical patients were retrospectively reviewed. Only patients aged 16 to 55 years who underwent primary hip surgery were included in this study. Patients with a history of revision hip surgery, previous knee surgery, hip dysplasia, hip synovitis, and/or incomplete radiographs and medical records were excluded from the study. Femoral torsion was measured via computed tomography imaging using transcondylar slices of the knee. Anterior capsular thickness was measured using oblique-sagittal sequences on a 3.0-T magnetic resonance imaging system. The association between anterior capsular thickness and related variables, including femoral torsion, was assessed via multiple linear regression. The patients were then divided into 2 groups to further confirm the effect of femoral torsion on capsular thickness: Patients in the study group had hips with moderate (20°-25°) or severe (>25°) antetorsion, whereas patients in the control group had hips with normal torsion (5°-20°) or retrotorsion (<5°). Anterior capsular thickness was also compared between the 2 groups.

RESULTS

A total of 156 patients (89 female patients [57.1%] and 67 male patients [42.9%]) were finally included in the study. The mean age and body mass index of the included patients were 35.8 ± 11.2 years and 22.7 ± 3.5, respectively. The mean femoral torsion for the entire study population was 15.9° ± 8.9°. Multivariable regression analysis showed that femoral torsion (P < .001) and sex (P = .002) were significantly correlated with anterior capsular thickness. Propensity-score matching yielded 50 hips in the study group and 50 hips in the control group on femoral torsion subanalysis. The results showed that anterior capsular thickness was significantly smaller in the study group than in the control group (3.8 ± 0.5 mm vs 4.7 ± 0.7 mm, P < .001).

CONCLUSIONS

Femoral torsion is significantly inversely correlated with anterior capsular thickness.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Lateral Center-edge Angle of 18° (Bone-Edge): Threshold for Hip Arthroscopy Treatment in Patients with Borderline Developmental Dysplasia of the Hip?

OBJECTIVE

Hip arthroscopy for the treatment of symptomatic borderline developmental dysplasia of the hip (BDDH) has been controversial. The purpose of this study was to retrospectively analyze minimum 2-year outcomes of BDDH after arthroscopic surgery and explore the criteria and thresholds of the lateral center-edge angle (LCEA) in arthroscopic surgery for BDDH.

METHODS

Data were retrospectively collected from patients aged 18-50 who underwent arthroscopic surgery for BDDH and had an LCEA 18-25° between September 2016 and June 2020. The consistency of interobserver and intraobserver measurements of bone-edge LCEA was analyzed. Patients were divided into two groups based on LCEA (18-20°and 20-25°) and the results of arthroscopy compared between groups. Patient-reported outcome (PRO) scores, consisting of the modified Harris hip score (mHHS), the visual analogue scale (VAS) and the international hip outcome tool-12 (IHOT-12), the minimal clinically important difference (MCID) and patient acceptable symptom status (PASS) were calculated.

RESULTS

In 52 patients with ≥2-year follow-up, female patients accounted for 71.2% and the mean age was 30.8 ± 8.4 years (range: 18 to 49 years). There was a high level of agreement when measuring the bone-edge LCEA definition of BDDH (Kappa = 0.921). Interobserver repeatability (ICC = 0.909, 95%CI: 0.847-0.947) and intraobserver repeatability (ICC = 0.944, 95%CI: 0.905-0.968) were excellent for bone-edge LCEA measurements. In addition to LCEA and Tönnis angle, there were no significant differences in α angle, neck stem angle, femoral anteversion angle, medial joint space, Tönnis grade of osteoarthritis, acetabular retroversion (8 sign), Cam deformity and anterior inferior iliac spine (AIIS) morphology between the two groups (p > 0.05). Intraoperative findings and procedures showed no statistical difference between groups (p > 0.05). The mean follow-up time was 44.4 ± 11.0 months (range: 25 to 64 months). Postoperative VAS, mHHS and IHOT-12 scores in the LCEA 18-20° group and the LCEA 20-25° group were significantly improved compared with those before surgery, and there was no statistically significant difference in the percentage of MCID and PASS (mHHS and iHOT-12) between the groups (p > 0.05).

CONCLUSION

Patients in the LCEA 18-20° group and the LCEA 20-25° group achieved favorable outcomes after arthroscopic surgery. LCEA 18° (bone-edge) should be the threshold for hip arthroscopic surgery in BDDH patients without obvious hip instability.

Factors influencing patient-reported outcomes following periacetabular osteotomy and open osteochondroplasty in the setting of borderline hip dysplasia

Aims

This study reports mid-term outcomes after periacetabular osteotomy (PAO) exclusively in a borderline hip dysplasia (BHD) population to provide a contrast to published outcomes for arthroscopic surgery of the hip in BHD.

Methods

We identified 42 hips in 40 patients treated between January 2009 and January 2016 with BHD defined as a lateral centre-edge angle (LCEA) of ≥ 18° but < 25°. A minimum five-year follow-up was available. Patient-reported outcomes (PROMs) including Tegner score, subjective hip value (SHV), modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. The following morphological parameters were evaluated: LCEA, acetabular index (AI), α angle, Tönnis staging, acetabular retroversion, femoral version, femoroepiphyseal acetabular roof index (FEAR), iliocapsularis to rectus femoris ratio (IC/RF), and labral and ligamentum teres (LT) pathology.

Results

The mean follow-up was 96 months (67 to 139). The SHV, mHHS, WOMAC, and Tegner scores significantly improved (p < 0.001) at last follow-up. According to SHV and mHHS, there were three hips (7%) with poor results (SHV < 70), three (7%) with a fair score (70 to 79), eight (19%) with good results (80 to 89), and 28 (67%) who scored excellent (> 90) at the last follow-up. There were 11 subsequent operations: nine implant removals due to local irritation, one resection of postoperative heterotopic ossification, and one hip arthroscopy for intra-articular adhesions. No hips were converted to total hip arthroplasty at last follow-up. The presence of preoperative labral lesions or LT lesions did not influence any PROMs at last follow-up. From the three hips that had poor PROMs, two have developed severe osteoarthritis (> Tönnis II), presumably due to surgical overcorrection (postoperative AI < -10°).

Conclusion

PAO is reliable in treating BHD with favourable mid-term outcomes. Concomitant LT and labral lesions did not negatively influence outcomes in our cohort. Technical accuracy with avoidance of overcorrection is essential in achieving successful outcomes.

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

BACKGROUND

The arthroscopic management of borderline hip dysplasia (BHD) is controversial, and long-term follow-up data are scarce. The purpose of this study was to report prospectively collected survivorship and patient-reported outcome measures (PROMs) at a minimum 10-year follow-up following primary hip arthroscopy with capsular plication and labral preservation in patients with BHD.

METHODS

Data were prospectively collected on all patients who underwent primary hip arthroscopy between September 2008 and September 2011. Patients with BHD (defined by a lateral center-edge angle [LCEA] between 18° and 25°) were included. Preoperative and minimum 10-year follow-up scores for the modified Harris hip score (mHHS), Nonarthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain were collected. Exclusion criteria were prior ipsilateral hip surgery, Workers' Compensation status, Tönnis grade of >1, previous hip conditions, or LCEA of <18°. Survivorship was defined as no conversion to total hip arthroplasty (THA). The risk factors for THA conversion were analyzed. The achievement rate for the minimal clinically important difference (MCID) was reported. A propensity-matched comparison with a control group without BHD was performed.

RESULTS

Forty-five (80%) of 56 eligible hips were included in this study: 38 hips (84%) of female patients and 7 hips (16%) of male patients. The mean patient age was 31.0 ± 12.9 years, and the mean patient body mass index (BMI) was 24.5 ± 5.4 kg/m2. The 10-year survivorship was 82.2%, and there was significant improvement in all PROMs and VAS pain from baseline to the minimum 10-year follow-up (p < 0.001). The odds of undergoing conversion to THA were 4.4 times higher for patients with a BMI of ≥23 kg/m2 and 7.1 times higher for patients who were ≥42 years of age. The MCID was achieved at high rates for the mHHS (79%), NAHS (79%), HOS-SSS (70%), and VAS pain (76%). The minimum 10-year survivorship, PROMs, and MCID achievement rates for the BHD group were comparable with those for the control group.

CONCLUSIONS

Patients with BHD who underwent primary hip arthroscopy with capsular plication and labral preservation demonstrated an overall survivorship of 82.2% and significant improvement in all PROMs and achieved the MCID at high rates at a minimum 10-year follow-up.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Mid- and Long-Term Outcomes Are Favorable for Patients With Borderline Dysplasia Undergoing Primary Hip Arthroscopy: A Systematic Review

PURPOSE

To evaluate midterm outcomes, long-term outcomes, and survivorship in the borderline dysplastic population after primary hip arthroscopy.

METHODS

A systematic review of current literature was performed with the following key words: "hip, "arthroscopy," "borderline dysplasia," "borderline hip dysplasia," "developmental dysplasia," "ten-year," "survivorship," "10-year," "5-year," "five year," "mid-term," "long-term," "outcomes," "arthroscopic," and "femoroacetabular impingement" in PubMed, Cochrane, and Scopus in March 2022 using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The following information was recorded: title, author, publication date, study design, demographic, number of hips, follow-up time, study period, indications for hip arthroscopy, patient-reported outcomes (PROs), characteristics of patients converting to total hip arthroplasty (THA), and rates of secondary surgeries and conversion to THA were recorded. Survivorship was defined as not converting to THA. Kappa values for the title/abstract and full-text screening were calculated. Forest plots were created for PROs that were included in 3 or more studies.

RESULTS

Six articles comprising 413 hips were included in the study. Three studies were Level III evidence, and 3 studies were Level IV evidence. Average follow-up ranged from 5.7 to 12.2 years. One study defined borderline hip dysplasia as lateral center-edge angle 18-25° and 5 defined it as lateral center-edge angle 20-25°. All studies included PROs and reported significant improvement after surgery in at least one PRO. Three studies reported clinical benefit and across the studies at least 70% of patients achieved minimum clinically important difference in at least one PRO. Rates of undergoing revision hip arthroscopy and THA ranged from 2.1% to 7% and 0% to 24%, respectively. Tönnis grade 2, Tönnis angle >15, and Outerbridge Grade IV cartilage damage were identified as predictors of conversion to THA.

CONCLUSIONS

Patients with borderline hip dysplasia undergoing primary hip arthroscopy demonstrated significant improvement in PROs at midterm and long-term follow-up. Survivorship at midterm follow-up was 98.2% (328/334 hips) and 76.3% (29/38 hips) at long-term follow-up.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III and Level IV studies.

Borderline Dysplastic Hips Undergoing Hip Arthroscopy Achieve Equivalent Patient Reported Outcomes When Compared With Hips With Normal Acetabular Coverage: A Systematic Review and Meta-Analysis

PURPOSE

To systematically review and meta-analyze studies reporting lateral center edge angle as it relates to patient-reported outcome (PRO) measures and clinically notable outcome assessments for patients undergoing hip arthroscopy for femoroacetabular impingement syndrome or labral pathology with borderline dysplastic hips (BDH).

METHODS

PubMed, EMBASE, and the Web of Science Core Collection databases were queried for articles evaluating lateral center edge angle as a predictor of PRO after hip arthroscopy. Articles were eligible for meta-analysis if they compared PROs measures between patients with normal acetabular coverage and borderline dysplasia and were at least level III evidence. Continuous random-effects models with standardized mean differences were used to compare postoperative Hip Outcome Score-Activities of Daily Living and sports subscales, modified Harris Hip Score, international Hip Outcome Tool scores, Satisfaction, and Visual Analog Scale Pain scores between normal coverage and borderline dysplastic groups.

RESULTS

Overall, 989 hips undergoing arthroscopy from six investigations were included in this meta-analysis, including 315 borderline dysplastic subjects (mean age 27.5 years) and 674 subjects with normal coverage (mean age 26.9 years). Borderline dysplastic and normal coverage cohorts were followed for an average of 37.0 and 36.8 months, respectively. Postoperative PRO measures (Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Subscale, modified Harris Hip Score, international Hip Outcome Tool-12, Satisfaction, and Visual Analog Scale Pain) collected approximately three years after hip arthroscopy were not markedly different between subjects with BDH when compared with patients with normal coverage.

CONCLUSIONS

In a meta-analysis of the available literature, patients with BDH are able to equally reach statistically similar clinical outcomes after isolated hip arthroscopy as compared with control subjects without dysplasia at short-term follow-up. A BDH should not be considered a contraindication to hip arthroscopy when optimal PRO achievement is the goal.

LEVEL OF EVIDENCE

Level III, Systematic Review and Meta-Analysis.

Does capsular repair make a difference in the integrity and thickness of anterior capsule in the setting of borderline hip dysplasia

BACKGROUND

Hip joint capsular ligaments serve a fundamental role in balancing functional mobility and joint stability. However, few studies had focused on postoperative capsule changes in patients with borderline developmental dysplasia of the hip (BDDH).

PURPOSE

To evaluate the integrity and thickness of anterior hip capsular thickness on pre and postoperative MRI in BDDH patients.

STUDY DESIGN

Case series study; Level of evidence III.

METHODS

A retrospective analysis was performed using data from BDDH patients who had arthroscopy between 2016 and 2019. Two groups were created and propensity-score matched based on whether the capsule was sutured. The study group comprised patients who have undergone routine capsule repair between 2018 and 2019. The control group includes BDDH patients with unrepaired capsulotomy between 2016 and 2018. Capsular integrity and thickness were measured on MRI before surgery and at least one year postoperatively. Furthermore, analysis was performed on correlations between the presence of a capsular defect and related factors.

RESULTS

Propensity-score matching yielded 37 hips in the repair group and 37 hips in the non-repair group. There were no significant differences detected in age, sex, and BMI between the two groups. MRI detected capsular defects in 3 hips (8.1%) in the repair group and 10 hips (27.0%) in the non-repair group (p = 0.032). The defect was found to be along the interportal capsulotomy line in all capsular defect cases. Moreover, the postoperative anterior capsule thickness in the study group was significantly thinner compared with preoperative (2.9 ± 0.5 mm vs 3.7 ± 0.6 mm; p < 0.001), and no significant difference was detected in the control group. There were no statistically significant correlations between the presence of a defect capsule and demographic characteristics such as patient age, sex, BMI, preoperative alpha angle, or lateral center-edge angle (LCEA).

CONCLUSION

The majority (91.9%) of the repaired hip capsules in BDDH patients remained closed compared with patients without repair (73.0%). The anterior capsule was significantly thinner in the zone of capsulotomy postoperative compared with preoperative in patients with unrepaired capsules. The presence of a defective capsule does not correlate with demographic factors.

Patients With Unhealed or Partially Healed Anterior Capsules After Hip Arthroscopy for Borderline Developmental Dysplasia of the Hips Have Inferior Patient-Reported Outcome Measures

PURPOSE

To evaluate the changes in anterior hip capsular thickness on pre- and postoperative magnetic resonance imaging (MRI) and their associated clinical outcomes in patients with borderline developmental dysplasia of the hip (BDDH).

METHODS

A minimum 2-year follow-up retrospective analysis was performed using data from symptomatic patients with BDDH who underwent hip arthroscopy with routine capsular closure between 2018 and 2020. An available postoperative hip MRI was a prerequisite for study inclusion. Capsular thickness at the capsulotomy zone was measured on MRI. An analysis of the correlations between anterior capsular thickness differences and demographic factors (including age, sex, body mass index, laterality, preoperative alpha angle and lateral center-edge angle, cartilage lesion grade, follow-up time, and capsule management) was performed. Patients with unhealed or partially healed capsules (study group) were propensity-score matched 1:1 to patients with completely healed capsules based on age, sex, body mass index, and follow-up time. Comparisons and analyses of the following parameters were completed for both groups: patient-reported outcomes (Hip Outcome Score-Activities of Daily Living [HOS-ADL], Hip Outcome Score-Sports-Specific Subscale [HOS-SSS], International Hip Outcome Tool 12-component form [iHOT-12], and modified Harris Hip Score), visual analog scale scores, radiographic measures, performed procedures, and complications.

RESULTS

Data were compiled for 59 patients' hips after patient selection. The majority of the repaired hip capsules remained closed (93.2%) at a minimum 2-year follow-up. Propensity-score matching was applied to distribute 25 subjects in the study group and 25 in the control group. The anterior capsule was significantly thinner postoperation in the study group (3.0 ± 1.2 mm vs 4.1 ± 0.6 mm; P < .001). Compared with the control group, patients in the study group had significantly inferior postoperative HOS-ADL (75.1 vs 83.5, P = .007), HOS-SSS (64.5 vs 77.1, P = .005), and iHOT-12 scores (56.1 vs 70.2, P = .006). In addition, patients in the study group were significantly less likely to achieve the minimum clinically important difference for the HOS-ADL score (52% vs 80%, P = .037) score and patient acceptable symptomatic state for the HOS-ADL score (32% vs 60%, P = .047).

CONCLUSIONS

The majority of the repaired hip capsules in patients with BDDH remained closed but not all capsules completely healed at a minimum 2-year follow-up. Patients with an unhealed or partially healed capsule had inferior HOS-ADL, HOS-SSS, and iHOT-12 scores and were less likely to achieve the minimum clinically important difference and patient acceptable symptomatic state for the HOS-ADL score.

LEVEL OF EVIDENCE

III, retrospective comparative prognostic study.

High-Level Athletes With Borderline Hip Dysplasia Achieve Favorable Outcomes and Return to Sport Rates Following Primary Hip Arthroscopy: Minimum 5-Year Outcomes Comparison to a Propensity-Matched Control Group

PURPOSE

(1) To report minimum 5-year patient-reported outcomes (PROs) and return to sport (RTS) rates in high-level athletes with borderline hip dysplasia (BHD) following primary hip arthroscopy for labral pathology and femoroacetabular impingement syndrome and (2) to compare results to a propensity-matched control group of athletes with normal acetabular coverage.

METHODS

Data were reviewed for surgeries performed between February 2009 and February 2016. Patients were eligible if they underwent primary hip arthroscopy in the setting of BHD (lateral center-edge angle [LCEA] 18-25°) and competed in professional, collegiate, or high school sports. Inclusion criteria were preoperative and minimum 5-year follow-up scores for the modified Harris Hip Score (mHHS), Non-Arthritis Hip Score, Hip Outcome Score-Sport Specific Subscale (HOS-SSS), and visual analog scale for pain. Rates of achieving the minimal clinically importance difference (MCID), patient acceptable symptomatic state (PASS), and maximum outcome improvement satisfaction threshold (MOIST) were recorded in addition to RTS. BHD athletes were matched by age at the time of surgery, sex, body mass index, Tönnis grade, follow-up time, sport type, and competition level to a control group of 58 athletes with normal acetabular coverage (LCEA 25°-40°) for comparison.

RESULTS

A total of 34 BHD athletes were included with a mean follow-up of 73.6 ± 10.7 months. BHD athletes showed significant improvements in all PROs, demonstrated high RTS rates (90.0%), and achieved PASS/MCID/MOIST for mHHS (MCID: 80.0%, PASS: 93.3%, MOIST: 80.0%) and HOS-SSS (MCID: 76.7%, PASS: 73.3%) at high rates. When compared to a propensity-matched group with normal acetabular coverage, BHD athletes demonstrated similar postoperative PROs, rates of achieving psychometric thresholds, and RTS rates (P > .05). Additionally, by the latest follow-up, no athlete in either group required conversion to total hip arthroplasty.

CONCLUSIONS

High-level athletes with BHD undergoing primary hip arthroscopy for labral pathology and femoroacetabular impingement syndrome may expect favorable midterm outcomes and high RTS rates. These results were comparable to a control group of athletes with normal coverage.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Hip Arthroscopy for Femoroacetabular Impingement Syndrome Shows Good Outcomes and Low Revision Rates, With Young Age and Low Postoperative Pain Score Predicting Excellent 5-Year Outcomes

PURPOSE

To evaluate the clinical outcomes of hip arthroscopy for femoroacetabular impingement syndrome (FAIS) and their predictors at a minimum 5 years' follow-up.

METHODS

We retrospectively analyzed patients with FAIS after first-time unilateral hip arthroscopy between January 2010 and July 2016. Patient-reported outcomes (PROs) included the validated modified Harries Hip Score (mHHS) and Visual Analog Scale for Pain (Pain VAS). We included patients with Tönnis grade 0 or 1 and reported PROs, and excluded patients with previous hip diseases or bilateral symptoms. Bivariate and multivariate analyses were used for data analysis.

RESULTS

We included 159 patients with a mean follow-up of 6.4 years, aged 36.18 ± 8.61 years, 41.5% female, and a mean body mass index of 23.61 ± 3.45. The mean postoperative mHHS was 88.82 ± 11.60, and the mean Pain VAS was 1.93 ± 1.89, significantly better than before surgery (P < .001). Postoperative alpha angle (P = .003) and lateral center edge angle (P < .001) were significantly decreased. Most patients (83.7%) achieved clinically important improvement based on patient-acceptable symptom state and minimal clinically important difference (MCID). The overall revision surgery rate was 2.5%. There were no conversions to total hip arthroplasty. Bivariate analysis indicated that age (P < .001), preoperative mHHS (P = .002), and postoperative Pain VAS (P <.001) correlated with postoperative mHHS at a minimum 5 years' follow-up. Multivariate regression analysis of MCID showed that age (P <.001), preoperative PROs (P < .01 for both), and postoperative Pain VAS (P < .001) were significant outcome predictors.

CONCLUSION

Patients with FAIS after first-time unilateral hip arthroscopy showed significant improvement in PROs at mid-term follow-up, with a low revision surgery rate. Young patients and those with low postoperative Pain VAS showed excellent outcomes at a minimum 5 years' follow-up.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Results of Arthroscopic Treatment for Femoroacetabular Impingement

Background. Femoroacetabular impingement (FAI) is one of the most frequent causes of hip pain and limited hip mobility in young and middle-aged patients. It is a result of repeated injury of hip structures, that leads to degenerative changes in hip labrum, cartilage and subchondral bone and provokes progressive development of hip osteoarthritis. Aim of study to analyze own experience of treating patients with femoroacetabular impingement and identify factors affecting its outcomes. Methods. Retrospective, uncontrolled, single-center clinical study included 128 patients with FAI which had 150 surgeries on 149 joints in in the period from 2013 to 2021. All patients underwent physical examination and X-ray diagnostics, their FAI type was identified. The alpha angle of external part of femoral head in anterior-posterior position and in the modified Dunn 45 position, as well as Tonnis angle, lateral central-marginal angle in Ogata modification and the height of articular gap along the lateral (LS) and medial edges (MS) of sclerosed acetabulum part were calculated. The i-HOT-33 and HOS scales were used to assess preoperative status and postoperative results. Results. The average follow-up period was 3.9 years (SD 1.71; min 1.05 and max 8.16). The study included 55 (43.0%) women and 73 (57.0%) men which underwent 64 (42.7%) and 86 (57.3%) surgeries respectively. The most common types of FAI, according to our data, were mixed type (53% of joints) and сam type (27.5% of joints). Insufficient coverage of the femoral head by the acetabulum (borderline dysplasia) in combination with the сam deformity of the femoral head was observed in 18.1%. Pincer-type FAI was observed in 1.4% of joints. We obtained the worst results with a combination of сam deformity and borderline dysplasia in comparison with cam- and mix-type FAI according to the i-HOT-33 and HOS scales. Patients age, deep cartilage damage, irreparable labrum damage and height decrease of the lateral part of the articular gap determined negative effect on treatment results according to the i-HOT-33 and HOS scales. Conclusion. Hip arthroscopy showed good short- and midterm outcomes in patients with FAI. Pain syndrome is most often manifested in patients with pathology of hip soft tissue structures concomitant to FAI. The combination of сam deformity and insufficient femoral head coverage, deep cartilage damage and a height decrease of the articular gap are important predictors of poor treatment results.

Use of Anatomic Radiographic Horizons for the Lateral Center-Edge Angle in the Classification of Hip Dysplasia

BACKGROUND

The lateral center-edge angle of Wiberg (LCEA) and Tönnis angle (TA) rely on a "horizon" that functions as a reference point for measurements of hip dysplasia on weightbearing anteroposterior pelvis radiographs. There are 3 different horizons that are currently utilized depending on surgeon preference: (1) a line parallel to the radiographic floor (F), (2) a line that connects the inferior portions of the acetabular teardrops (ATs), or (3) a line that connects the ischial tuberosities (ITs). It is imperative to accurately assess the degree of hip dysplasia on initial workup to select the appropriate surgical intervention.

PURPOSE

To assess how the choice of a radiographic horizon affects the measurements of the LCEA and TA. The secondary purpose was to assess how the horizon affected the classification of hips as either normal, borderline dysplastic, or dysplastic.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

The LCEA and TA were measured on all preoperative weightbearing anteroposterior pelvis radiographs for 186 consecutive patients who underwent hip preservation surgery between February 2016 and November 2020 (140 hip arthroscopic procedures, 46 combined hip arthroscopic procedures with periacetabular osteotomy), 3 times per hip, each time using an F, AT, and IT horizon. The Student t test was used to analyze the differences in the measurements of the LCEA and TA, and discordance rates in the dysplasia classification between horizons were quantified.

RESULTS

For the entire study population, the mean LCEA_F (23.4°± 7.4°) was significantly greater than the mean LCEA_IT (23.1°± 7.2°) (95% CI, -0.634 to -0.003; P = .047) and mean LCEA_AT (23.0°± 7.1°) (95% CI, -0.723 to -0.139; P = .004). There was no difference between the LCEA_IT and LCEA_AT (95% CI, -0.305 to 0.080; P = .251). When stratified by hip arthroscopic surgery, the mean LCEA_F (26.3°± 5.6°) was significantly greater than the mean LCEA_AT (25.8°± 5.3°) (95% CI, -0.845 to -0.162; P = .004). Overall, there was a 17.7% and 18.3% discordance rate in the dysplasia classification using the LCEA_IT and LCEA_AT compared with the LCEA_F, respectively. There were no statistically significant differences between the mean TA_IT, TA_AT, and TA_F for the entire study population, the arthroscopic surgery group, and the combined arthroscopic surgery and periacetabular osteotomy group.

CONCLUSION

There was no statistical difference between the AT and IT horizons for LCEA measurements. The dysplasia classification was in better agreement between the 2 anatomic horizons compared with the F horizon. The TA was not affected by changes in the horizon.

Periacetabular osteotomy after failed hip arthroscopy demonstrates improved outcomes in a heterogenous patient population: a systematic review

PURPOSE

To evaluate the literature on patients undergoing periacetabular osteotomy after failed hip arthroscopy (PAO-FHA) for (1) patient demographics and hip morphology, (2) changes in preoperative to postoperative patient-reported outcomes (PROs), and (3) PROs in comparison to primary periacetabular osteotomy (PAO) patients.

METHODS

A systematic literature search of Pubmed, CINAHL/Medline, and cochrane databases was performed in accordance with PRISMA guidelines. The search phrase was "(periacetabular osteotomy or PAO or rotational osteotomy) and (hip arthroscopy or arthroscopic)". The titles, abstracts, and full texts were screened for studies on PAO-FHA. Study quality was assessed, and relevant data were collected. A meta-analysis was not performed due to study heterogeneity.

RESULTS

The search identified 7 studies, including 151 hips (148 patients, 93.9% female) undergoing PAO-FHA, out of an initial 593 studies, with three Level IV and four Level III studies. Mean time from hip arthroscopy to PAO ranged from 17.0 to 29.6 months. Heterogenous hip morphologies and radiologic findings prior to PAO were observed, though patients most frequently demonstrated moderate-to-severe dysplasia (mean or median lateral center edge angle < 20°) and minimal osteoarthritis (Tönnis grade 0 or 1). In all 5 studies that reported concomitant procedures with PAO, femoral and/or acetabular osteoplasty was performed via arthroscopy or arthrotomy. Following PAO-FHA, radiographic acetabular coverage and PROs improved in all 6 studies that reported postoperative outcomes. All four comparative studies of primary PAO vs. PAO-FHA included patients with mean or median LCEAs < 20°, reporting mixed outcomes for the optimal treatment approach.

CONCLUSION

PAO-FHA is reported in a heterogenous patient population that frequently includes hips with moderate-to-severe dysplasia and minimal osteoarthritis. Regardless of hip morphology or concomitant procedures, all studies that reported postoperative outcomes demonstrated improved PROs following PAO-FHA.

LEVEL OF EVIDENCE

Level IV.

Arthroscopic labral repair combined with less invasive open-shelf acetabuloplasty for patients with developmental dysplasia of the hip

Hip arthroscopy has become widely used for intra-articular lesions, such as labral tears and femoral acetabular impingement. However, its use in patients with developmental dysplasia of the hip (DDH) has been controversial and has historically demonstrated mixed results, as acetabular dysplasia may cause instability due to insufficient bony coverage of the femoral head, thus causing excessive stress on the repaired labrum and cartilage. We devised a combined hip arthroscopic labral repair and a less invasive open-shelf procedure using a small skin incision as an anterolateral portal in hip arthroscopy. This novel procedure may improve the stability of the repaired labrum with a bony covering in a minimally invasive manner. Moreover, the shelf procedure can be performed under direct vision in a comparatively safe and precise manner. In total, 13 hips with DDH underwent the procedure for labral tears. All patients were females, with a mean age of 30 years. The mean follow-up period was 33 months. The mean Harris hip score improved from 74.2 to 93.6, and Oxford Hip score improved from 32.4 to 19.3. According to the Tönnis classification, the grade of arthritis preoperatively was grade 0 for nine hips and grade I for four hips. No radiographic progression of osteoarthritis was observed. It is possible that this novel procedure could be an effective treatment for labral tears with DDH and may prevent the early onset of secondary osteoarthritis. In this technical tip, we describe hip arthroscopic labral repair combined with a less invasive open-shelf acetabuloplasty in further detail.

Arthroscopic Treatment of Mild/Borderline Hip Dysplasia with Concomitant Femoroacetabular Impingement-Literature Review

Purpose of Review

This literature review aims to survey the current knowledge about the management FAI in the setting of borderline hip dysplasia.

Recent Findings

With better understanding, hip arthroscopy has recently been advocated for treating mild or borderline hip dysplasia (BDH) with concomitant femoroacetabular impingement (FAI) despite early studies that condemned its use. Recent outcome data have demonstrated that hip arthroscopy is a viable option in BDH, with and without FAI, and has been gaining wider acceptance. Hip arthroscopy can address the concomitant soft tissue and bony intra-articular pathologies and obviate the necessity for other surgeries. Moreover, hip arthroscopy may be used as an adjuvant treatment to other procedures such as a periacetabular osteotomy (PAO).

Summary

Hip arthroscopy for BDH is an evolving procedure with promising short- and mid-term outcomes. The combination of BDH and FAI is becoming recognized as a problem in its own right, requiring dedicated treatment.

Editorial Commentary: Hip Arthroscopy for Femoroacetabular Impingement in Patients With Borderline Dysplasia Does Not Result in Inferior Outcomes Compared With Outcomes in Patients Without Dysplasia: Do Not Fear

The treatment of adult borderline hip dysplasia remains challenging and continues to be a subject of controversy. The preferred treatment for hip instability and acetabular undercoverage is periacetabular osteotomy. However, patients with painful hips and associated femoroacetebular impingement, microinstability, or no instability may benefit from arthroscopic surgery. Short-term studies have reported favorable clinical outcomes. Traditionally, the lateral center-edge angle was used to determine hip dysplasia. More recently the femoro-epiphyseal acetabular roof (FEAR) index was introduced as a measure for borderline dysplasia. In general, a FEAR index of less than 5° indicates hip instability. When using a FEAR index of more than 2° as a cut-off for hip instability and borderline dysplasia, arthroscopic hip surgery can achieve very similar clinical outcomes to patients with a FEAR index of less than 2°. However low and unequal sample sizes have potentially resulted in both type I and II errors, reducing internal study validity. Although this may be a step in the right direction, further high-quality studies are required to understand patients' characteristics on diagnosis, prognosis, outcomes of surgical interventions, and long-term disease progression for adult borderline hip dysplasia.

Incidence of heterotopic ossification following hip arthroscopy is low: considerations for routine prophylaxis

PURPOSE

This scoping review aims to map and summarise the available literature on heterotopic ossification (HO) following hip arthroscopy, with particular focus on incidence, distribution as per Brooker classification, efficacy of prophylactic measures and factors that may influence the likelihood of production of HO.

METHODS

A computer-based search was performed on PubMed, Embase, Emcare, Cinahl, ISI web of science and Scopus using the terms 'heterotopic ossification' and 'hip arthroscopy'. Articles reporting heterotopic ossification following hip arthroscopy for any condition were included after two-stage title/abstract and full-text screening.

RESULTS

Of the 663 articles retrieved, 45 studies were included. The proportion of patients with HO ranged from 0 to 44%. The majority of the cases were either Brooker grade I or II. Of the six studies investigating the effect of NSAID prophylaxis, five reported a significantly lower incidence of heterotopic ossification associated with its use. Weak evidence suggests that an outside-in arthroscopic approach, no capsular closure, male sex and mixed cam and pincer resection may be associated with an increased risk of HO.

CONCLUSION

Although there is a large variation in rates of HO following hip arthroscopy in the current literature, the majority of studies report a low incidence. Evidence exists advocating the administration of post-operative NSAIDs to reduce the incidence of HO following hip arthroscopy. This, combined with the low risk of complications, means there is a favourable risk-benefit ratio for prophylactic NSAID used in HA. Future research should work to identify patient clinical and demographic factors which may increase the risk of development of HO, allowing clinicians to risk stratify and select only specific patients who would benefit from receiving NSAID prophylaxis.

Ten-Year Outcomes After Hip Arthroscopy in Patients With Femoroacetabular Impingement and Borderline Dysplasia

BACKGROUND

The role of hip arthroscopy in the treatment of patients with borderline hip dysplasia is controversial and evolving.

PURPOSE

To evaluate outcomes at a minimum 10-year follow-up in patients who underwent hip arthroscopy for femoroacetabular impingement in a hip with borderline dysplasia.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All hips that underwent labral repair between June 2006 and March 2009 for femoroacetabular impingement with borderline dysplasia were included if they had a lateral center-edge angle of 20° to 25°, had primary hip arthroscopy for the diagnosis of femoroacetabular impingement, and were aged 18 to 70 years. Patients were excluded if they had previous hip surgery, avascular necrosis, or fracture. Kaplan-Meier survivorship was performed, with survivorship defined as avoidance of conversion to total hip arthroplasty (THA).

RESULTS

A total of 45 patients met the inclusion criteria, and 38 were contacted at a minimum 10 years postoperatively (84%; mean ± SD, 12 ± 1.3 years). There were 23 women and 15 men with an average age of 41 ± 9.6 years (range, 25-69). Twenty patients were ≥40 years of age. In this patient cohort, survivorship was 87% at 5 years and 79% at 10 years for conversion to THA. Of the 38 patients included, 9 were converted to THA (24%), and 3 required revision hip arthroscopy (7%). Patient age, Tönnis grade, microfracture of cartilage lesions, and Tönnis angle >15° were associated with conversion to THA. No statistically significant differences were found between those who underwent conversion to THA and those who did not regarding lateral center-edge angle, Sharp angle, or alpha angle. Significant improvements were seen at follow-up of 12 years (range, 10-13) for the modified Harris Hip Score (58 to 83; P = .002), Hip Outcome Score-Activities of Daily Living (70 to 87; P = .003), Hip Outcome Score-Sport (47 to 76; P = .004), and Western Ontario and McMaster Universities Osteoarthritis Index (31 to 10; P = .001). At follow-up, >80% maintained the minimal clinically important difference for the Hip Outcome Score (Activities of Daily Living and Sport) with no differences between patients aged <40 and ≥40 years.

CONCLUSION

Risk factors for conversion to THA after hip arthroscopy in the borderline dysplastic hip included older age, higher Tönnis grades, grade 4 chondral lesions that were microfractures, and Tönnis angle >15°. In those patients who did not convert to THA, improvement in outcome measures was seen at 10 years. Careful patient selection is critical to the success of this procedure.

The influence of prior arthroscopy on outcomes of primary total lower extremity arthroplasty: A systematic review and meta-analysis

PURPOSE

The primary purpose of this systematic review and meta-analysis was to investigate the impact of prior arthroscopy on postoperative revisions, complications, and other clinical outcomes after conversion total lower extremity arthroplasty.

METHODS

Two individual researchers conducted the platform searches on the Embase, PubMed, Cochrane Central, and Google Scholar electronic databases from inception to June 02, 2021. We identified cohort trials that compared the outcomes of patients who underwent primary THA or TKA in the prior arthroscopy or control groups. The primary outcome was revision, and secondary outcomes included reoperation, patient-reported outcomes, and postoperative complications. A modified version of the Downs and Black tool was used to assess the methodological quality of the non-randomized cohort studies.

RESULTS

Of the 23 included studies with 319946 cases, 18 were matched retrospectively and five were non-matched retrospectively. Methodological quality was high in ten studies and moderate in thirteen studies. Our analysis demonstrated that TKA or THA patients with prior arthroscopy were associated with an increased risk of revision, reoperation, infection, and aseptic loosening. THA patients with prior arthroscopy were also associated with an increased risk of dislocation. Furthermore, there were no significant intergroup differences in periprosthetic fracture, range of motion, Harris Hip Score, or Knee Society Score.

CONCLUSION

Arthroscopy performed before total lower extremity arthroplasty substantially increased the revision, reoperation, infection, and aseptic loosening rates. THA patients with prior arthroscopy were also associated with an increased risk of dislocation. Patients should be counseled on the potential increased risks associated with conversion total lower extremity arthroplasty after prior arthroscopy. Further research is needed to better characterize these findings.

Femoro-Epiphyseal Acetabular Roof (FEAR) Index and Anterior Acetabular Coverage Correlate With Labral Length in Developmental Dysplasia of the Hip

PURPOSE

The aim of this study was to evaluate the association between labral length and radiographic parameters of lateral and anterior acetabular coverage and the femoro-epiphyseal acetabular roof (FEAR) index in patients with developmental dysplasia of the hip (DDH).

METHODS

We retrospectively analyzed data from patients with DDH who visited our hip joint clinic for the first time due to hip symptoms. DDH presence was defined as a lateral center-edge angle (LCEA) of ≤25°. The labral lengths on the anterior and lateral sides were measured on central axial and central coronal slices of T1-weighted magnetic resonance imaging, respectively. The Pearson correlation coefficients (r) and simple linear regression analyses were performed to determine the association of the lateral and anterior labral lengths with the radiographic parameters, including the LCEA, acetabular roof obliquity, FEAR index, anterior wall index, and vertical center anterior angle.

RESULTS

This study included 88 patients, with a mean age of 39.6 ± 11.8 years. There were 65 women and 23 men. The lateral and anterior labral lengths correlated with all parameters of dysplasia. Specifically, the lateral labral length had a strong positive correlation with the FEAR index (R = 0.65, P < .001). The anterior labral length had a strong negative correlation with the anterior wall index (R = -0.66, P < .001).

CONCLUSIONS

The lateral labral length had a strong positive correlation with the FEAR index. Furthermore, the anterior labral length had a correlation with the anterior dysplasia.

LEVEL OF EVIDENCE

Level III, retrospective cross-sectional study.

[Recent research progress of hip-preserving treatment for adolescents and adults with developmental dysplasia of the hip]

Objective

To review the imaging evaluation, treatment progress, and controversy related to developmental dysplasia of the hip (DDH) in adolescents and adults.

Methods

The domestic and abroad hot issues related to adolescents and adults with DDH in recent years, including new imaging techniques for assessing cartilage, controversies over the diagnosis and treatment of borderline DDH (BDDH), and the improvement and prospect of peracetabular osteotomy (PAO) were summarized and analyzed.

Results

DDH is one of the main factors leading to hip osteoarthritis. As the understanding of the pathological changes of DDH continues to deepen, the use of delayed gadolinium-enhanced MRI of cartilage can further evaluate the progress of osteoarthritis and predict the prognosis after hip preservation. There are still controversies about the diagnosis and treatment of BDDH. At the same time, PAO technology and concepts are still being improved.

Conclusion

Cartilage injury and bony structure determine the choice of surgical methods and postoperative prognosis of hip preservation surgery. The hip preservation of adolescent and adult DDH patients will move towards the goal of individualization and accuracy.

One Bony Morphology, Two Pathologic Entities: Sex-Based Differences in Patients With Borderline Hip Dysplasia Undergoing Hip Arthroscopy

BACKGROUND

Sex-based differences have been largely uncharacterized for patients with borderline hip dysplasia (BHD) undergoing hip arthroscopy.

PURPOSE

To evaluate for sex-based differences in clinical and pathologic characteristics as well as surgical outcomes in patients with BHD undergoing hip arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Between January 2011 and December 2018, data were prospectively collected on all patients with BHD undergoing primary hip arthroscopy. Patients were included if they had preoperative and minimum 2-year postoperative scores for the modified Harris Hip Score (mHHS), Non-arthritic Hip Score (NAHS), and visual analog scale for pain. Patients with previous ipsilateral hip conditions or surgery, Tönnis grade >1, lateral center-edge angle <18° or >25°, or workers' compensation status were excluded. Patients were then divided by sex and propensity score matched in a 1:1 ratio for body mass index, age, and Tönnis grade. The rates of patients who achieved the minimal clinically important difference were recorded for the mHHS and NAHS. The rates of achieving the patient acceptable symptomatic state for the mHHS were calculated.

RESULTS

A total of 344 hips met the inclusion criteria, and 317 hips (92%) had adequate follow-up. Propensity score matching created cohorts of 109 male and 109 female patients. Male patients had significantly higher preoperative average alpha angles (69.79° vs 58.17°, P < .001), more often requiring a femoroplasty (97.2% vs 83.5%, P < .001), and had higher rates of complex labral tearing (50.5% vs 33.0%, P < .001). Male patients also had higher rates of grade 3 and 4 acetabular labral articular disruption (62.4% vs 19.3%, P < .001) and higher rates of grade 3 and 4 acetabular cartilage injury (59.6% vs 20.2%, P < .001) requiring a microfracture more frequently (32.1% vs 7.3%, P < .001). Female patients more typically had painful internal snapping requiring iliopsoas fractional lengthening (60.6% vs 32.1%, P < .001). Female patients also underwent capsular plication more regularly to address hip instability (79.8% vs 45.9%, P < .001). Male and female patients showed significant improvements in all outcome scores after surgery (P < .001). Female patients achieved the minimal clinically important difference for the NAHS at higher rates (85.3% vs 71.6%, P = .020).

CONCLUSION

Female and male patients with BHD who underwent hip arthroscopy achieved favorable outcomes but had notably dissimilar pathology. Hence, although they share similar acetabular bony morphology, male and female patients with BHD may represent 2 very different pathologic entities.

The role of iliocapsularis in hip pathology: a scoping review

The iliocapsularis is a relatively unheard-of muscle, located deep in the hip covering the anteromedial capsule of the hip joint. Little is known about this constant muscle despite its clinical relevance. The aims of this scoping review are to collate the various research studies reporting on the detailed anatomy and function of iliocapsularis and to demonstrate how inter-individual differences in iliocapsularis can be used as a clinical adjunct in guiding diagnosis and treatment of certain hip joint pathologies. A computer-assisted literature search was conducted based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our review found 13 studies including 384 cases meeting our inclusion criteria. About 53.8% of the studies involved human cadavers. The current scoping review indicates the relevant anatomy of the iliocapsularis, being a small muscle which arises from the inferior border of the anterior inferior iliac spine and anteromedial capsule of the hip joint, inserting distal to the lesser trochanter. Therefore, based upon these anatomical attachments, iliocapsularis acts as a dynamic stabilizer by tightening the anterior capsule of the hip joint. Implications of this association may be that the muscle is hypertrophied in dysplastic or unstable hips. Determining the size of the iliocapsularis could be of conceivable use in patients with hip symptoms featuring signs of both borderline hip dysplasia and subtle cam-type deformities. Although future research is warranted, this study will aid physicians to understand the clinical importance of the iliocapsularis.

Achieving Successful Outcomes in High-Level Athletes With Borderline Hip Dysplasia Undergoing Hip Arthroscopy With Capsular Plication and Labral Preservation: A Propensity-Matched Controlled Study

BACKGROUND

Return to sports (RTS) rates and patient-reported outcomes (PROs) after hip arthroscopy in athletes with borderline dysplasia (BD) have not been established.

PURPOSE

(1) To report minimum 2-year PROs and RTS rates in high-level athletes with BD who underwent hip arthroscopy for labral pathology in the setting of microinstability and (2) to compare clinical results with those of a matched control group of athletes with normal acetabular coverage.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were reviewed for surgery performed between January 2012 and July 2018. Patients were considered eligible if they received a primary hip arthroscopy in the setting of BD (lateral center-edge angle, 18°-25°) and competed in professional, collegiate, or high school sports. Inclusion criteria included preoperative and minimum 2-year follow-up scores for the modified Harris Hip Score, Non-arthritic Hip Score, Hip Outcome Score-Sport Specific Subscale, and visual analog scale for pain. Athletes with BD were matched to a control group of athletes with normal acetabular coverage (lateral center-edge angle, 25°-40°).

RESULTS

A total of 65 patients with BD were included in the study with a mean ± standard deviation follow-up of 47.5 ± 20.4 months. Athletes with BD showed significant improvement in all outcome measures recorded, demonstrated high RTS rates (80.7%), and achieved the minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) for the Hip Outcome Score-Sport Specific Subscale at high rates (MCID, 90.8%; PASS, 75.4%). When compared with a propensity-matched control group with normal acetabular coverage, capsular plication was performed more commonly in the BD group (93.8% vs 82.7%; P = .037). PROs and RTS, PASS, and MCID rates were similar between the BD and control groups (P > .05).

CONCLUSION

High-level athletes with BD who undergo primary hip arthroscopy for labral pathology in the setting of microinstability may expect favorable PROs and RTS rates at minimum 2-year follow-up. These results were comparable with those of a control group of athletes with normal coverage.

Complications of hip preserving surgery

Preoperative evaluation of the pathomorphology is crucial for surgical planning, including radiographs as the basic modality and magnetic resonance imaging (MRI) and case-based additional imaging (e.g. 3D-CT, abduction views).

Hip arthroscopy (HAS) has undergone tremendous technical advances, an immense increase in use and the indications are getting wider. The most common indications for revision arthroscopy are labral tears and residual femoroacetabular impingement (FAI).

Treatment of borderline developmental dysplastic hip is currently a subject of controversy. It is paramount to understand the underlining problem of the individual hip and distinguish instability (dysplasia) from FAI, as the appropriate treatment for unstable hips is periacetabular osteotomy (PAO) and for FAI arthroscopic impingement surgery.

PAO with a concomitant cam resection is associated with a higher survival rate compared to PAO alone for the treatment of hip dysplasia. Further, the challenge for the surgeon is the balance between over- and undercorrection.

Femoral torsion abnormalities should be evaluated and evaluation of femoral rotational osteotomy for these patients should be incorporated to the treatment plan.

Cite this article: EFORT Open Rev 2021;6:472-486. DOI: 10.1302/2058-5241.6.210019

Hip Dysplasia

Acetabular dysplasia represents a structural pathomorphology associated with hip pain, instability, and osteoarthritis. The wide spectrum of dysplasia anatomically refers to a 3-dimensional volumetric- and surface area-based insufficiency in coverage and is classified based on the magnitude and location of undercoverage. Borderline dysplasia has been variably defined and leads to management challenges. In symptomatic dysplasia, treatment addresses coverage with periacetabular osteotomy. Concomitant simultaneous or staged hip arthroscopy has significant advantages to address intra-articular pathology. In nonarthritic individuals, there is evidence PAO alters the natural history of dysplasia and decreases the risk of hip arthritis and total hip arthroplasty.

Revision Hip Arthroscopy in the Borderline Dysplastic Population: Reporting Outcomes With Minimum 2-Year Follow-up, With a Subanalysis Against a Propensity-Matched Nondysplastic Control Group

BACKGROUND

Hip arthroscopy in patients with borderline dysplasia continues to be surrounded by controversy. Even more controversial is the management of the failed hip arthroscopy in this population. There is a paucity of studies in contemporary literature regarding outcomes after arthroscopic revision surgery.

PURPOSE

(1) To report minimum 2-year patient-reported outcome (PRO) scores in patients with borderline dysplasia who underwent revision hip arthroscopy and (2) to compare these PRO scores with those of a propensity-matched control group without dysplasia who underwent revision hip arthroscopy.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Data were prospectively collected between August 2009 and November 2017. Inclusion criteria were revision arthroscopic surgery, capsular plication, and baseline and minimum 2-year follow-up for the following PROs: modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), Hip Outcome Score-Sports Specific Subscale (HOS-SSS), and visual analog scale (VAS) for pain. Patients with Tönnis grade >1 or previous hip conditions were excluded. Two groups were created: a study group with borderline dysplasia (lateral center-edge angle [LCEA], 18°-25°) and a control group without dysplasia (LCEA, 25°-40°). Groups were propensity-matched in a 1:3 ratio for sex, age, body mass index, and follow-up time.

RESULTS

A total of 22 revision borderline dysplastic hips (21 patients) had a minimum 2-year follow-up during the study period. Patients in this group reported significant improvements for all PROs from baseline and achieved the minimal clinically important difference (MCID) for the mHHS at a rate of 70%. Moreover, 21 borderline dysplastic hips (21 patients) were matched to 63 control hips (63 patients). Mean LCEA for the study and control groups was 22.6 ± 1.7 and 32.0 ± 5.0, respectively. Both groups reported similar improvement in all PROs. The rate for achieving the MCID for the mHHS and VAS was similar between groups; however, the control group had higher rates of meeting the MCID for the HOS-SSS and NAHS (P = .042 and P = .025, respectively). The rates of conversion to hip arthroplasty were 7.9% (n = 5) in the control group and 23.8% (n = 5) in the borderline dysplasia propensity-matched group (P = .052). The rate of re-revision arthroscopy was 11.1% (n = 7) in the control group and 19.0% (n = 4) on the borderline dysplasia group (P = .350).

CONCLUSION

After revision hip arthroscopy, significant improvement was obtained for all PROs in patients with borderline dysplasia at a minimum 2-year follow-up. Moreover, outcomes, patient satisfaction, the rate for achieving the MCID for the mHHS and VAS, and the rate for secondary surgery were similar to those of a propensity-matched control group without dysplasia. Nevertheless, there was a nonsignificant trend toward higher secondary procedures in the study group; therefore, arthroscopic revision surgery in the borderline patients should be approached with measured prognosis.

Total hip arthroplasty for Crowe type IV developmental dysplasia of the hip combined with intertrochanteric fracture: a case report and literature review

BACKGROUND

Total hip arthroplasty for Crowe type IV developmental dysplasia of the hip (DDH) is a complex procedure. Crowe type IV DDH combined with intertrochanteric frature is very rare.

CASE PRESENTATION

A 75-year-old patient suffering from left hip pain after a fall was sent to our hospital. Plain radiographs and computed tomography scans were used to diagnose this patient with DDH combined with an intertrochanteric fracture. We conducted a total hip arthroplasty using an S-rom prosthesis following subtrochanteric shortening osteotomy in this patient, after which steel wires were used to fix the intertrochanteric fracture. The patient did not suffer any significant intraoperative or postoperative complications, and treatment was sufficient to overcome lower leg abnormalities. The patient was encouraged to resume walking with support at 3 days post-surgery, and at 6-month postoperatively he had regained the majority of his original range of motion. At 10-month postoperatively, the intertrochanteric fracture and subtrochanteric osteotomy of left femur had healed effectively,and the patient's VAS and mHSS scores had improved significantly.

CONCLUSIONS

Total hip arthroplasty is an effective approach to treat patients suffering from Crowe type IV DDH combined with an intertrochanteric fracture, and can achieve satisfactory clinical outcomes.

Editorial Commentary: Arthroscopy for Borderline Developmental Dysplasia of the Hip: Selection Determines the Outcomes

Although the literature has presented results that favored arthroscopic procedures in treating borderline developmental dysplasia of the hip (BDDH), it remains controversial whether arthroscopic surgery would be better than periacetabular osteotomy for BDDH. Instead of a debate on the application of arthroscopy, the issue worthy of discussion should be distinguishing suitable BDDH candidates for hip arthroscopy. First, identification of patients with real BDDH is critical for making management choices. Second, it should be distinguished whether the major symptoms result from mechanical lesions or functional hip instability. Third, once hip arthroscopy is suggested for BDDH patients, relative contraindications such as advanced age and osteoarthritis should be taken into consideration, in addition to labral repair and capsular closure or plication intraoperatively. In conclusion, more long-term and high-grade evidence is still demanded to end the debate, but we believe that an individualized management strategy based on an accurate diagnosis and comprehensive assessment will bring optimal outcomes for BDDH patients.