A traffic light grading system of hip dysplasia to predict the success of arthroscopic hip surgery

Background: The role of hip arthroscopy in dysplasia is controversial. Purpose: Determine the 7-year joint preservation rate following hip arthroscopy in hip dysplasia and identify anatomical and intra-operative features that predict success of hip preservation with arthroscopic surgery allowing formulation of an evidence-based classification. Study Design: Cohort Study; Level of evidence: 3 Methods: Between 2008 and 2013, 111 hips with dysplastic features [acetabular index (AI) > 10° and/or centre-edge angle (CEA) <25°] having undergone an arthroscopy were identified. Clinical, radiological and operative findings and type of procedure performed were reviewed. Radiographic evaluations of the operated hip [acetabular index (AI), centre-edge angle (CEA), extrusion index] were performed. Outcome measures included whether the hip was preserved at follow-up, pre- and post-operative NAHS and HOOS scores. We calculated AI and CEA factored (AIf and CEAf respectively) by a measure of articular wear as follows: AIf = AI x (number of UCL wear zones +1) CEAf = CEA / (number of UCL zones + 1) A contour plot of the resulting probability value of failure for every combination of AIf and CEAf allowed for the determination of the zones with the lowest and highest incidence of failure to preserve the hip respectively. Results: The mean AI and CEA were 7.8° and 18.0°, respectively. At a mean follow-up of 4.4 years, 33 hips had failed requiring a hip arthroplasty. The 7- year joint survival was 68%. The mean improvement in NAHS and HOOS were 7.8 and 23 points respectively. The zone with the greatest chance of joint preservation (odds ratio: 10, p<0.001) was AIf: 0 – 15 and CEAf: 15 – 25 (Green Zone); on the contrary the zone with the greatest chance of failure (odds ratio: 10, p<0.001) was AIf: 20 – 100 and CEAf : 0 – 10 (Red Zone). Conclusion: Overall, the 7- year hip survival in hip dysplasia appears inferior compared to reports of Femoro-Acetabular Impingement cases. Hip arthroscopy is associated with excellent chance of hip preservation in mild (Green Zone) dysplasia (AI< 15° & CEA: 15 – 25°) and no (or little) articular wear. Hip arthroscopy should not be performed in cases with severe (Red Zone) dysplasia (AI> 20° & CEA< 10°)

Pelvic Positioning in the Supine Position Leads to More Consistent Cup Orientation after Total Hip Arthroplasty

Aims: This study aims to 1) Determine the difference in pelvic position that occurs between surgery and radiographic, supine, post-operative assessment; 2) Examine how the difference in pelvic position influences subsequent cup orientation and 3) Establish whether pelvic position, and thereafter cup orientation differences exist between THAs performed in the supine versus the lateral decubitus positions. Materials and Methods: 321 THAs who had intra-operative, post-cup impaction, AP pelvic radiograph, in the operative position were studied; 167 were performed with patient supine (anterior approach), whilst 154 were performed in lateral decubitus (posterior approach). Cup inclination/anteversion was measured from intra- and post-operative radiographs and difference (Δ) was determined. The target zone was inclination/anteversion of 40/20°±10°. Change in pelvic position (tilt, rotation, obliquity) between surgery and post-operatively was calculated from Δinclination/anteversion using the Levenberg-Marquardt algorithm. Results: The post-operative inclination/anteversion was 40°±8/23°±9. 74 had Δinclination and/or Δanteversion>±10° (21%). Intra-operatively (compared to post-operative), the pelvis was on average 4°±10 anteriorly tilted; 1°±10 internally rotated and 1°±5 adducted. Having Δinclination and/or Δanteversion >±10° was associated with a 3.5 odds ratio of having a cup outside the target. A greater proportion of hips operated in the lateral decubitus had Δinclination and/or Δanteversion >±10° (54/153), compared to supine (8/167) (p<0.001). A greater number of cups achieved the target orientation in supine (120/167;73%), compared to lateral position (67/153;44%) (p<0.001). Intra-operatively, pelvis was more anteriorly tilted (p<0.001) and hemi-pelvis was more internally rotated (p=0.04) in lateral position. Conclusion: Pelvic movement is significantly less in supine position, which leads to more consistent cup orientation. Significant differences in pelvic tilt and rotation were seen in the lateral position. Clinical Relevance: Understanding the differences in pelvic orientation and cup orientation between supine and lateral decubitus positions may facilitate better intraoperative practices for surgeons

Placental CRH as a signal of pregnancy adversity and impact on fetal neurodevelopment

Early life is a period of considerable plasticity and vulnerability and insults during that period can disrupt the homeostatic equilibrium of the developing organism, resulting in adverse developmental programming and enhanced susceptibility to disease. Fetal exposure to prenatal stress can impede optimum brain development and deranged mother’s HPA axis stress responses can alter the neurodevelopmental trajectories of the offspring. Corticotropin-releasing hormone (CRH) and glucocorticoids, regulate fetal neurogenesis and while CRH exerts neuroprotective actions, increased levels of stress hormones have been associated with fetal brain structural alterations such as reduced cortical volume, impoverishment of neuronal density in the limbic brain areas and alterations in neuronal circuitry, synaptic plasticity, neurotransmission and GPCR signalling. Emerging evidence highlight the role of epigenetic changes in fetal brain programming, as stress-induced methylation of genes encoding molecules that are implicated in HPA axis and major neurodevelopmental processes. These serve as molecular memories and have been associated with long term modifications of the offspring’s stress regulatory system and increased susceptibility to psychosomatic disorders later in life. This review summarises our current understanding on the roles of CRH and other mediators of stress responses on fetal neurodevelopment

High Variability of Acetabular Offset in Primary Hip Osteoarthritis Influences Acetabular Reaming—A Computed Tomography–Based Anatomic Study

Background: The objectives of the present study were to (1) evaluate the accuracy and reliability of native acetabular offset (AO) measurements performed on conventional supine anterior-posterior (ap) pelvis radiographs with reference to computed tomography (CT) in patients with end-stage hip osteoarthritis (OA); (2) determine the minimum and maximum amount of medialization of the center of rotation (COR) simulating different reaming techniques; and (3) identify patients at increased risk of excessive medialization of the COR.Methods: A consecutive series of corresponding 131 CT scans and radiographs of patients with primary hip OA was evaluated using validated software for three-dimensional acetabular and femoral measurements. We simulated the implantation of a hemispherical press-fit cup comparing anatomic and conventional reaming techniques and assessed corresponding changes in AO.Results: Standardized ap pelvis radiographs allowed for an accurate and reliable assessment of AO compared with CT. Cup placement in the most lateral position (anatomic reaming technique) resulted in a mean implant-related medialization of 5.9 ± 3.4 mm. Anatomic cup placement did not require reaming to the true floor in 64 hips (49%). With the conventional reaming technique, the total medialization of the COR (implant-related and reaming-related) was 6.8 ± 2.9, with 34% of cases having a medialization ≥8 mm.Conclusion: The present study highlights the variability of acetabular anatomy in patients with primary OA. AO can be accurately and reliably determined on conventional radiographs and appears to be independent of femoral shape and geometry. Depending on the preferred reaming technique a substantial number of patients appear at risk for excessive cup medialization

Asymmetrical hip loading correlates with metal ion levels in patients with metal-on-metal hip resurfacing during sit-to-stand

The occurrence of pseudotumours following metal-on-metal hip resurfacing arthroplasty (MoMHRA) has been associated with high serum metal ion levels and consequently higher than normal bearing wear. Measuring ground reaction force is a simple method of collecting information on joint loading during a sit-to-stand (STS). We investigated vertical ground reaction force (VGRF) asymmetry during sit-to-stand for 12 MoMHRA patients with known serum metal ion levels. Asymmetry was assessed using two methods: a ratio of VGRF for implanted/unimplanted side and an absolute symmetry index (ASI). It was found that subjects with high serum metal ion levels preferentially loaded their implanted sides. The difference between the two groups was most apparent during the first 22% of STS. VGRF ratio showed significant and strong correlation with serum metal ion levels (Spearman's rho = 0.8, p = 0.003). These results suggest that individual activity patterns play a role in the wear of MoMHRA and preferential loading of an implanted limb during the initiation of motion may increase the wear of metal-on-metal hip replacements. </jats:p

What is the early/mid-term survivorship and functional outcome after Bernese Periacetabular Osteotomy in a Pediatric Surgeon Practice?

BACKGROUND: The Bernese periacetabular osteotomy (PAO) is a recognized joint-preserving procedure. Achieving joint stability without creating impingement is important, but the orientation target that best balances these sometimes competing goals has not yet been clearly defined. Moreover, the learning curve of this challenging procedure has not been described. QUESTIONS/PURPOSES: The purposes of this study were (1) to determine the 10-year survivorship and functional outcome after Bernese PAO in a single-surgeon series; (2) to review which patient, surgical, and radiographic factors might predict outcome after the procedure; and (3) to define the learning curve for target acetabular correction. METHODS: The first 68 PAOs performed for symptomatic hip dysplasia were retrospectively evaluated. None have been lost to followup with followup less than 2 years. Endpoints for the lost to followup (n = 2) are at the time of when last seen. During the study period, the same surgeon performed 562 pelvic osteotomies (including Salter, Pemberton, Dega and Chiari) and 64 shelf acetabuloplasties. Bernese PAO was used only for symptomatic dysplasia (center-edge angle < 25° and nonhorizontal acetabular roof) in developmentally mature hips without evidence of major joint incongruence or subluxation. Most patients were female (n = 49 [60 hips, 88%]); mean age at operation was 25 years (SD 7). Sixteen hips had previous hip procedures. The study’s mean followup was 8 years (range, 2–18 years). Patient-reported functional outcome was obtained using the WOMAC score (best-worst: 0–96). Radiographic parameters of dysplasia (acetabular index [AI], center-edge angle [CEA], congruency, Tönnis grade, and joint space) were evaluated from preoperative and postoperative radiographs using computer software. RESULTS: The 10-year survival rate was 93% (95% confidence interval [CI], 82%–100%); four patients underwent further surgery to the hip in the study period. The mean WOMAC was 12 (range, 0–54). Factors that influenced survival included joint congruency (100% versus 78%; 95% CI, 61%–96%; p = 0.03) and acetabular orientation correction achieved (AI(postoperative) < 15° [100% versus 65%; 95% CI, 43–88; p < 0.001] and CEA(postoperative) 20° to 40° [100% versus 71.9%; 52.8–100; p < 0.001]). Better WOMAC scores were seen if postoperative AI < 15° (7 versus 25, p = 0.005) and CEA between 20° and 40° (7 versus 23, p = 0.005) were achieved. The chances of obtaining acetabular correction within this range improved after the 20(th) procedure (30% versus 70%, p = 0.008). CONCLUSIONS: This study reports excellent results after Bernese PAO in the hands of an experienced pediatric hip surgeon. We advocate cautious correction of the acetabular fragment. Future studies should concentrate on how to determine what the optimal target is and how to achieve it intraoperatively, minimizing the learning curve associated with it. LEVEL OF EVIDENCE: Level III, therapeutic study

Periacetabular osteotomy with or without arthroscopic management in patients with hip dysplasia: Study protocol for a multicenter randomized controlled trial

BACKGROUND: Hip dysplasia is one of the most common causes of hip arthritis. Its incidence is estimated to be between 3.6 and 12.8% (Canadian Institute for Health Information, Hip and knee replacements in Canada, 2017-2018: Canadian joint replacement registry annual report, 2019; Jacobsen and Sonne-Holm, Rheumatology 44:211-8, 2004). The Periacetabular Osteotomy (PAO) has been used successfully for over 30 years (Gosvig et al., J Bone Joint Surg Am 92:1162-9, 2010), but some patients continue to exhibit symptoms post-surgery (Wyles et al., Clin Orthop Relat Res 475:336-50, 2017). A hip arthroscopy, performed using a small camera, allows surgeons to address torn cartilage inside the hip joint. Although both procedures are considered standard of care treatment options, it is unknown whether the addition of hip arthroscopy improves patient outcomes compared to a PAO alone. To delay or prevent future joint replacement surgeries, joint preservation surgery is recommended for eligible patients. While previous studies found an added cost to perform hip arthroscopies, the cost-effectiveness to Canadian Health care system is not known. METHODS: Patients randomized to the experimental group will undergo central compartment hip arthroscopy prior to completion of the PAO. Patients randomized to the control group will undergo isolated PAO. Patient-reported quality of life will be the primary outcome used for comparison between the two treatment groups as measured by The International Hip Outcome Tool (iHOT-33) (Saberi Hosnijeh et al., Arthritis Rheum 69:86-93, 2017). Secondary outcomes will include the four-square step test and sit-to-stand (validated in patients with pre-arthritic hip pain) and hip-specific symptoms and impairment using the HOOS; global health assessment will be compared using the PROMIS Global 10 Score; health status will be assessed using the EQ-5D-5L and EQ VAS questionnaires (Ganz et al., Clin Orthop Relat Res 466:264-72, 2008) pre- and post-operatively. In addition, operative time, hospital length of stay, adverse events, and health services utilization will be collected. A sub-group of patients (26 in each group) will receive a T1rho MRI before and after surgery to study changes in cartilage quality over time. A cost-utility analysis will be performed to compare costs and quality-adjusted life years (QALYs) associated with the intervention. DISCUSSION: We hypothesize that (1) concomitant hip arthroscopy at the time of PAO to address central compartment pathology will result in clinically important improvements in patient-reported outcome measures (PROMs) versus PAO alone, that (2) additional costs associated with hip arthroscopy will be offset by greater clinical improvements in this group, and that (3) combined hip arthroscopy and PAO will prove to be a cost-effective procedure. TRIAL REGISTRATION: ClinicalTrials.gov NCT03481010 . Registered on 6 March 2020. Protocol version: version 3

A traffic light grading system of hip dysplasia to predict the success of arthroscopic hip surgery

Background: The role of hip arthroscopic surgery in dysplasia is controversial. Purpose: To determine the 7-year joint preservation rate after hip arthroscopic surgery in hip dysplasia and identify anatomic and intraoperative features that predict the success of hip preservation with arthroscopic surgery, allowing the formulation of an evidence-based classification system. Study Design: Case-control study; Level of evidence, 3. Methods: Between 2008 and 2013, 111 hips with dysplastic features (acetabular index [AI] &gt;10° and/or lateral center-edge angle [LCEA] &lt;25°) that underwent arthroscopic surgery were identified. Clinical, radiological, and operative findings and the type of procedure performed were reviewed. Radiographic evaluations of the operated hip (AI, LCEA, extrusion index) were performed. Outcome measures included whether the hip was preserved (ie, did not require arthroplasty) at follow-up and the preoperative and postoperative Non-Arthritic Hip Score (NAHS) and Hip disability and Osteoarthritis Outcome Score (HOOS). The AI and LCEA were calculated, factored by a measure of articular wear (AIf and LCEAf, respectively), according to the University College Hospital, London (UCL) grading system as follows: AIf = AI × (number of UCL wear zones + 1), and LCEAf = LCEA / (number of UCL wear zones + 1). A contour plot of the resulting probability value of failure for every combination of AIf and LCEAf allowed for the determination of the zones with the lowest and highest incidences of failure to preserve the hip. Results: The mean AI and LCEA were 9.8° and 18.0°, respectively. At a mean follow-up of 4.5 years (range, 0.4-8.3 years), 33 hips had failed, requiring hip arthroplasty. The 7-year joint survival rate was 68%. The mean improvements in the NAHS and HOOS were 11 ( P = .001) and 22.8 ( P &lt; .001) points, respectively. The zone with the greatest chance of joint preservation (odds ratio, 10; P &lt; .001) was the green zone, with an AIf of 0° to 15° and an LCEAf of 15° to 25°; in contrast, the zone with the greatest chance of failure (odds ratio, 10; P &lt; .001) was the red zone, with an AIf of 20° to 100° and an LCEAf of 0° to 10°. Conclusion: Overall, the 7-year hip survival rate in hip dysplasia appears inferior compared with that reported in femoroacetabular impingement (78%). Hip arthroscopic surgery is associated with an excellent chance of hip preservation in mild dysplasia (green zone: AI = 0°-15°, LCEA = 15°-25°) and no articular wear. The authors advise that the greatest caution should be used when considering arthroscopic options in cases of severe dysplasia (red zone: AI &gt;20° and/or LCEA &lt;10°). </jats:sec