Mean 20-year Followup of Bernese Periacetabular Osteotomy

The goal of the Bernese periacetabular osteotomy is to correct the deficient acetabular coverage in hips with developmental dysplasia to prevent secondary osteoarthrosis. We determined the 20-year survivorship of symptomatic patients treated with this procedure, determined the clinical and radiographic outcomes of the surviving hips, and identified factors predicting poor outcome. We retrospectively evaluated the first 63 patients (75 hips) who underwent periacetabular osteotomy at the institution where this technique was developed. The mean age of the patients at surgery was 29years (range, 13-56years), and preoperatively 24% presented with advanced grades of osteoarthritis. Four patients (five hips) were lost to followup and one patient (two hips) died. The remaining 58 patients (68 hips) were followed for a minimum of 19years (mean, 20.4years; range, 19-23years) and 41 hips (60%) were preserved at last followup. The overall mean Merle d'Aubigné and Postel score decreased in comparison to the 10-year value and was similar to the preoperative score. We observed no major changes in any of the radiographic parameters during the 20-year postoperative period except the osteoarthritis score. We identified six factors predicting poor outcome: age at surgery, preoperative Merle d'Aubigné and Postel score, positive anterior impingement test, limp, osteoarthrosis grade, and the postoperative extrusion index. Periacetabular osteotomy is an effective technique for treating symptomatic developmental dysplasia of the hip and can maintain the natural hip at least 19years in selected patients. Level of Evidence: Level III, prognostic study. See the Guidelines for Authors for a complete description of levels of evidenc

Joint-preserving Surgery Improves Pain, Range of Motion, and Abductor Strength After Legg-Calvé-Perthes Disease

Background: Patients after Legg-Calvé-Perthes disease (LCPD) often develop pain, impaired ROM, abductor weakness, and progression of osteoarthritis (OA) in early adulthood. Based on intraoperative observations during surgical hip dislocation, we established an algorithm for more detailed characterization of the underlying pathomorphologies with a proposed joint-preserving surgical treatment. Questions/purposes: We asked if patients after LCPD treated with our algorithm experienced (1) reduced pain; (2) improved hip function; and/or (3) prevention of OA progression; we then determined (4) the intraoperative damage patterns; (5) the survival of the hip; and (6) factors predicting the need for a conversion to THA; radiographic progression of OA; a Merle d'Aubigné-Postel score below 15 at last followup; and/or the need for revision surgery. Methods: We retrospectively reviewed 53 patients after LCPD who underwent joint-preserving surgery (40 surgical hip dislocations, eight acetabular osteotomies, four combined procedures, and one intertrochanteric osteotomy). We obtained Merle d'Aubigné-Postel scores to assess pain; OA was assessed using Tönnis grades. Survival and predictive factors were calculated with the univariate Cox regression. Fifty of the 53 patients were evaluated at a minimum of 5.1years (mean, 8.2years; range, 5.1-12.8years). Results: Pain and hip function improved at followup from a median of 4 points to 5 points. The mean increase in Tönnis grades at last followup was 0.3 to 0.8. The survival of surgery at 5years was 86%; 13 factors related to survival. Conclusion: Patients with symptoms resulting from pathomorphologic deformities after LCPD benefit from joint-preserving surgery with specific treatment of individual structural abnormalities. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidenc

Surgical hip dislocation with relative femoral neck lengthening and retinacular soft-tissue flap for sequela of Legg-Calve-Perthes disease.

OBJECTIVE Correction of post-LCP (Legg-Calve-Perthes) morphology using surgical hip dislocation with retinacular flap and relative femoral neck lengthening for impingent correction reduces the risk of early arthritis and improves the survival of the native hip joint. INDICATIONS Typical post-LCP deformity with external and internal hip impingement due to aspherical enlarged femoral head and shortened femoral neck with high riding trochanter major without advanced osteoarthritis (Tönnis classification ≤ 1) in the younger patient (age < 50 years). CONTRAINDICATIONS Advanced global osteoarthritis (Tönnis classification ≥ 2). SURGICAL TECHNIQUE By performing surgical hip dislocation, full access to the hip joint is gained which allows intra-articular corrections like cartilage and labral repair. Relative femoral neck lengthening involves osteotomy and distalization of the greater trochanter with reduction of the base of the femoral neck, while maintaining vascular perfusion of the femoral head by creation of a retinacular soft-tissue flap. POSTOPERATIVE MANAGEMENT Immediate postoperative mobilization on a passive motion device to prevent capsular adhesions. Patients mobilized with partial weight bearing of 15 kg with the use of crutches for at least 8 weeks. RESULTS In all, 81 hips with symptomatic deformity of the femoral head after healed LCP disease were treated with surgical hip dislocation and offset correction between 1997 and 2020. The mean age at operation was 23 years; mean follow-up was 9 years; 11 hips were converted to total hip arthroplasty and 1 patient died 1 year after the operation. The other 67 hips showed no or minor progression of arthrosis. Complications were 2 subluxations due to instability and 1 pseudarthrosis of the lesser trochanter; no hip developed avascular necrosis

Development of acetabular retroversion in LCPD hips-an observational radiographic study from early stage to healing.

BACKGROUND Acetabular retroversion is observed frequently in healed Legg-Calvé-Perthes disease (LCPD). Currently, it is unknown at which stage and with what prevalence retroversion occurs because in non-ossified hips, retroversion cannot be measured with standard radiographic parameters. METHODS In a retrospective, observational study; we examined pelvic radiographs in children with LCPD the time point of occurrence of acetabular retroversion and calculated predictive factors for retroversion. Between 2004 and 2017, we included 55 children with a mean age of 5.7 ± 2.4 years at diagnosis. The mean radiographic follow-up was 7.0 ± 4.4 years. We used two new radiographic parameters which allow assessment of acetabular version in non-ossified hips: the pelvic width index and the ilioischial angle. They are based on the fact that the pelvic morphology differs depending on the acetabular version. These parameters were compared among the four Waldenström stages and to the contralateral side. Logistic regression analysis was performed to determine predictive factors for acetabular retroversion. RESULTS Both parameters differed significantly among the stages of Waldenström (p < 0.003 und 0.038, respectively). A more retroverted acetabulum was found in stage II and III (prevalence ranging from 54 to 56%) compared to stage I and IV (prevalence ranging from 23 to 39%). In hips of the contralateral side without LCPD, the prevalence of acetabular retroversion was 0% in all stages for both parameters. Predictive factors for retroversion were younger age at stage II and IV, collapse of the lateral pillar in stage II or a non-dysplastic hip. CONCLUSIONS This is the first study evaluating acetabular version in children with LCPD from early stage to healing. In the developing hip, LCPD may result in acetabular retroversion and is most prevalent in the fragmentation (stage II) and early healing stage (stage III). Partial correction of acetabular retroversion can occur after healing. This has a potential clinical impact on the timing and type of surgical correction, especially in pelvic osteotomies for correction of acetabular version. LEVEL OF EVIDENCE Level III, retrospective observational study

Posterior Hip Impingement at Maximal Hip Extension in Female Patients With Increased Femoral Version or Increased McKibbin Index and Its Effect on Sports Performance.

BACKGROUND The location of posterior hip impingement at maximal extension in patients with posterior femoroacetabular impingement (FAI) is unclear. PURPOSE To investigate the frequency and area of impingement at maximal hip extension and at 10° and 20° of extension in female patients with increased femoral version (FV) and posterior hip pain. STUDY DESIGN Cross-sectional study; Level of evidence, 3. METHODS Osseous patient-specific 3-dimensional (3D) models were generated of 50 hips (37 female patients, 3D computed tomography) with a positive posterior impingement test and increased FV (defined as >35°). The McKibbin index (combined version) was calculated as the sum of FV and acetabular version (AV). Subgroups of patients with an increased McKibbin index >70° (24 hips) and FV >50° (20 hips) were analyzed. A control group of female participants (10 hips) had normal FV, normal AV, and no valgus deformity (neck-shaft angle, <139°). Validated 3D collision detection software was used for simulation of osseous impingement-free hip extension (no rotation). RESULTS The mean impingement-free maximal hip extension was significantly lower in patients with FV >35° compared with the control group (15° ± 15° vs 55° ± 19°; P 35° had osseous posterior extra-articular ischiofemoral hip impingement. At 20° of extension, the frequency of posterior extra-articular ischiofemoral impingement was significantly higher for patients with a McKibbin index >70° (83%) and for patients with FV >35° (76%) than for controls (0%) (P 70° versus <70° (251 vs 44 mm2; P = .001). CONCLUSION The limited hip extension found in our study could theoretically affect the performance of sports activities such as running, ballet dancing, or lunges. Therefore, although not examined directly in this study, these activities are not advisable for these patients. Preoperative evaluation of FV and the McKibbin index is important in female patients with posterior hip pain before hip preservation surgery (eg, hip arthroscopy)

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

Can gadolinium contrast agents be replaced with saline for direct MR arthrography of the hip? A pilot study with arthroscopic comparison.

OBJECTIVE To compare image quality and diagnostic performance of preoperative direct hip magnetic resonance arthrography (MRA) performed with gadolinium contrast agent and saline solution. METHODS IRB-approved retrospective study of 140 age and sex-matched symptomatic patients with femoroacetabular impingement, who either underwent intra-articular injection of 15-20 mL gadopentetate dimeglumine (GBCA), 2.0 mmol/L ("GBCA-MRA" group, n = 70), or 0.9% saline solution ("Saline-MRA" group, n = 70) for preoperative hip MRA and subsequent hip arthroscopy. 1.5 T hip MRA was performed including leg traction. Two readers assessed image quality using a 5-point Likert scale (1-5, excellent-poor), labrum and femoroacetabular cartilage lesions. Arthroscopic diagnosis was used to calculate diagnostic accuracy which was compared between groups with Fisher's exact tests. Image quality was compared with the Mann-Whitney U tests. RESULTS Mean age was 33 years ± 9, 21% female patients. Image quality was excellent (GBCA-MRA mean range, 1.1-1.3 vs 1.1-1.2 points for Saline-MRA) and not different between groups (all p > 0.05) except for image contrast which was lower for Saline-MRA group (GBCA-MRA 1.1 ± 0.4 vs Saline-MRA 1.8 ± 0.5; p  0.999/p = 0.904) and acetabular (GBCA-MRA 86%/ 83% versus Saline-MRA 89%/87%; p = 0.902/p = 0.901) and femoral cartilage lesions (GBCA-MRA 97%/ 99% versus Saline-MRA 97%/97%; both p > 0.999). CONCLUSION Diagnostic accuracy and image quality of Saline-MRA and GBCA-MRA is high in assessing chondrolabral lesions underlining the potential role of non-gadolinium-based hip MRA. KEY POINTS • Image quality of Saline-MRA and GBCA-MRA was excellent for labrum, acetabular and femoral cartilage, ligamentum teres, and the capsule (all p > 0.18). • The overall image contrast was lower for Saline-MRA (Saline-MRA 1.8 ± 0.5 vs. GBCA-MRA 1.1 ± 0.4; p  0.999), acetabular cartilage damage (89% vs. 86%; p = 0.902), femoral cartilage damage (97% vs. 97%; p > 0.999), and extensive cartilage damage (97% vs. 93%; p = 0.904)

Demographic Changes in Pelvic Fracture Patterns at a Swiss Academic Trauma Center from 2007 to 2017.

BACKGROUND Increasing life expectancy has led to higher incidence of fragility fractures of the pelvis. These demographic changes may have a direct impact on fracture patterns. The goal was (1) to evaluate demographical trends in patients with pelvic ring injuries at a tertiary Swiss trauma center and (2) to analyze the influence on fracture patterns. METHODS We performed a retrospective cross-sectional study including 958 patients (mean age 57 ± 21 years, 48% women) with a pelvic ring injury between 2007 and 2017. Fractures were classified according to Tile, Young and Burgess or Rommens and Hofmann (fragility fractures) using conventional and CT imaging. Low-energy fractures were defined as fractures resulting from fall from standing height or less. Fracture classifications, age, gender, injury severity score (ISS) and trauma mechanism were compared using analysis of variance (ANOVA) or chi-square test. Cluster analysis was performed to identify groups with similarities in fracture patterns and demographic parameters. RESULTS From 2007 to 2017, the frequency of pelvic ring injuries increased by 115% (increase per decade), mean age increased by 15% (p = 0.031). A trimodal age distribution was found; highest increase for fractures occurred in the 'older' (265%) patient group. Low-energy fracture was the most common trauma mechanism (43% of all fractures, an increase of 249%). Changes in fracture pattern showed a disproportioned increase of 'lateral compression (LC)' fractures (LC type 1 in 64%) or partially stable fracture (B2: with 39%). In patient aged over 65 years, the strongest increase was found for 'non-displaced posterior' fractures with an overall prevalence of 62%. Five clusters were found with the most frequent cluster representing 'older female patients with low-energy fracture (LC, Tile type B)' in 30%. CONCLUSION The current results corroborate the trend of increasing frequency of fragility fractures in an aging society. The demographic shift has a direct impact on fracture pattern with a disproportionate increase in partially stable compression fracture of the pelvis. LEVEL OF EVIDENCE Level III

Diagnosis of acetabular retroversion: Three signs positive and increased retroversion index have higher specificity and higher diagnostic accuracy compared to isolated positive cross over sign.

Objectives The crossover-sign (COS) is a radiographic sign for diagnosis of acetabular-retroversion(AR) in patients with femoroacetabular-impingement (FAI) but overestimates AR. Three signs combined with retroversion-index (RI) could potentially improve diagnostic-accuracy. Aims (1)To calculate central acetabular-version (AV, CT/MRI) in patients with isolated positive COS and in patients with three radiographic signs for AR on radiographs (AP).(2)To calculate diagnostic performance of positive COS and of three signs combined with retroversion-index (RI) > 30% on radiographs (AP) to detect global AR (AV < 10°, CT/MRI). Methods A retrospective, IRB-approved, controlled diagnostic study comparing radiographic signs for AR (AP radiographs) with MRI/CT-based measurement of central AV was performed. 462 symptomatic patients (538 hips) with FAI or hip-dysplasia were compared to control-group (48 hips). Three signs for AR(on radiographs) were analyzed: COS, posterior-wall-sign and ischial-spine-sign. RI (synonym cross-over-index) quantifies overlap of anterior and posterior wall in case of positive COS. Diagnostic performance for COS and for three signs combined with RI > 30% to detect central AV < 10° (global AR) was calculated. Results (1)Central AV was significantly (p  30% on radiographs compared to patients with positive COS (18 ± 7°).(2)Sensitivity and specificity of three signs combined with RI > 30% on radiographs was 85% and 63% (87% and 23% for COS). Negative-predictive-value (NPV) was 94% (93% for COS) to rule out global AR (AV < 10°, CT/MRI). Diagnostic accuracy increased significantly (p < 0.001) from 31% (COS) to 68% using three signs. Conclusion Improved specificity and diagnostic accuracy for diagnosis of global AR can help to avoid misdiagnosis. Global AR can be ruled out with a probability of 94% (NPV) in the absence of three radiographic signs combined with retroversion-index < 30% (e.g. isolated COS positive)