Residual Acetabular Dysplasia in the Reduced Hip

Protective effect of modified lange "second position" for developing avascular necrosis following closed reduction for developmental dysplasia of the hip

BACKGROUND

Developmental Dysplasia of the Hip (DDH) is a condition affecting hip joint development in children, presenting multiple manifestations. Immobilization methods to ensure hip concentricity, such as the human position and modified Lange position, vary in effectiveness and risks, especially avascular necrosis. The purpose of this study was to identify whether closed reduction (CR), with two different immobilization techniques, is effective in avoiding complications such as residual hip dysplasia (RHD), re-dislocation, and Avascular Necrosis (AVN).

METHODS

A total of 66 patients with DDH (84 hips) were treated with two different techniques of immobilization (groups A and B); the mean age at the time of reduction was 8 (6-13) months. The rates of RHD, Re-dislocation, and AVN were determined with a minimum follow-up of 48 months in both techniques.

RESULTS

The Chi-square analysis conducted across the study groups unveiled that patients in Group B demonstrated a protective effect against AVN compared to those in Group A (OR: 0.248, 95% CI: 0.072-0.847, p = 0.026). However, no statistically significant differences were found between the groups concerning RHD (p = 0.563) and re-dislocation (p = 0.909).

CONCLUSIONS

After the initial Human Position immobilization, the second cast with the modified Lange "second position" demonstrated a protective effect compared with maintaining the Human Position immobilization throughout the immobilization period, reducing the likelihood of AVN development in patients undergoing closed reduction for developmental dysplasia of the hip.

Fate of acetabular dysplasia after closed and open reduction of hips in children with developmental hip dislocation

Acetabular underdevelopment (acetabular dysplasia) is a common finding in children with hip dislocation, and residual acetabular dysplasia can remain after hip reduction. Residual dysplasia leads to unsatisfactory long-term outcomes and osteoarthritis. Dynamics of acetabular dysplasia [measured as Acetabular Index (AI)] in a pediatric cohort that underwent open (OR) or closed reduction are reported. Retrospective data from six tertiary pediatric orthopedic centers were gathered. Hips were classified as having 'Critical', 'Monitoring', or 'Normal' acetabular dysplasia based on age-adjusted normative AI measurements. From 193 hips, 108 (56%) underwent open reduction. Children younger than 24 months had a strong AI decline but children > 24 months did not. Among 78 hips with critical dysplasia at time of OR, 36 (46.2%) remained critical and 19 (24.4%) underwent an acetabular osteotomy (AO) during follow-up. CR hips had a similar AI decline in patients younger and older than 12 months. Among 51 hips with critical dysplasia at the time of CR, 13 (25.5%) remained critical and 21 (41.2%) underwent AO during follow-up. Acetabular dysplasia improves with AI decreasing in children who undergo OR and CR under the age of 2 years with slower acetabular remodeling afterwards. Around 2/3 of patients with AI in the critical range at CR or OR either underwent AO or had significant acetabular dysplasia at final follow-up. Our data supports considering simultaneous AO at the time of OR for hips with AI in the critical range or children who undergo hip open reduction after 24 months of age. Level of Evidence: Level III.

Factors influencing outcomes of pelvic osteotomy for residual acetabular dysplasia following closed reduction in patients with developmental dysplasia of the hip

To investigate the factors influencing outcome of pelvic osteotomy (PO) for residual acetabular dysplasia (RAD) following closed reduction (CR) in patients with developmental dysplasia of the hip (DDH). We retrospectively reviewed 91 patients (95 hips) with DDH who underwent PO for RAD. Tönnis grade, Acetabular index, Center Edge Angle, Reimer's Index (RI), and avascular necrosis of the femoral head (AVN) were assessed. Hips were divided into satisfactory (Severin I/II) and unsatisfactory group (Severin III/IV). Finally, 87 hips (91.5%) had satisfactory and 8 (8.5%) unsatisfactory outcomes. The RI before PO was significantly higher in unsatisfactory (49.6 ± 9%) than in satisfactory group (30.6%±11.8%). All patients without AVN had satisfactory outcome, while it was 78.9% of patients with AVN. Logistic regression analysis showed that higher AVN grade and RI before PO were risk factors for unsatisfactory outcome. Satisfactory outcome was obtained in all hips with RI < 33% before PO, while it was 79.5% if RI > 33% before PO (79.5%). There was no difference in the satisfactory rate between patients undergoing open reduction (66.7%) and those not undergoing (83.3%). The rate of satisfactory outcome in patients undergoing femoral osteotomy (63.6%) was lower than those without it (100%). In patients with RAD following CR, good outcome can be expected after PO alone. AVN and preoperative RI > 33% are risk factors for poor outcome. Additional open reduction and femoral osteotomy do not significantly improve outcome of PO in patients with preoperative RI > 33%.

Resolving residual acetabular dysplasia following successful brace treatment for developmental dysplasia of the hip in infants

Aims

Radiological residual acetabular dysplasia (RAD) has been reported in up to 30% of children who had successful brace treatment of infant developmental dysplasia of the hip (DDH). Predicting those who will resolve and those who may need corrective surgery is important to optimize follow-up protocols. In this study we have aimed to identify the prevalence and predictors of RAD at two years and five years post-bracing.

Methods

This was a single-centre, prospective longitudinal cohort study of infants with DDH managed using a published, standardized Pavlik harness protocol between January 2012 and December 2016. RAD was measured at two years' mean follow-up using acetabular index-lateral edge (AI-L) and acetabular index-sourcil (AI-S), and at five years using AI-L, AI-S, centre-edge angle (CEA), and acetabular depth ratio (ADR). Each hip was classified based on published normative values for normal, borderline (1 to 2 standard deviations (SDs)), or dysplastic (> 2 SDs) based on sex, age, and laterality.

Results

Of 202 infants who completed the protocol, 181 (90%) had two and five years' follow-up radiographs. At two years, in 304 initially pathological hips, the prevalence of RAD (dysplastic) was 10% and RAD (borderline) was 30%. At five years, RAD (dysplastic) decreased to 1% to 3% and RAD (borderline) decreased to < 1% to 2%. On logistic regression, no variables were predictive of RAD at two years. Only AI-L at two years was predictive of RAD at five years (p < 0.001). If both hips were normal at two years' follow-up (n = 96), all remained normal at five years. In those with bilateral borderline hips at two years (n = 21), only two were borderline at five years, none were dysplastic. In those with either borderline-dysplastic or bilateral dysplasia at two years (n = 26), three (12%) were dysplastic at five years.

Conclusion

The majority of patients with RAD at two years post-brace treatment, spontaneously resolved by five years. Therefore, children with normal radiographs at two years post-brace treatment can be discharged. Targeted follow-up for those with abnormal AI-L at two years will identify the few who may benefit from surgical correction at five years' follow-up.

Effects of different doses of dexmedetomidine combined with sufentanil in intravenous controlled analgesia after Salter osteotomy in children

Background

This study aimed to investigate the effect of different doses of dexmedetomidine combined with sufentanil on postoperative analgesia in developmental hip dislocation in children after Salter osteotomy.

Methods

The clinical data of 98 children with developmental hip dislocation, who underwent Salter osteotomy in our center between January 2020 and February 2023, were selected. The children were randomly divided into four groups based on the application of patient-controlled intravenous analgesia (sufentanil + granisetron ± dexmedetomidine). All children received 1 µg/kg/day of sufentanil and 3 mg of granisetron. Group A did not receive dexmedetomidine, and Groups B, C, and D received 0.5, 0.75, and 1.0 µg/kg/day of dexmedetomidine, respectively. The pain indicators and immune factor levels of children in each group were compared.

Results

The heart rate (HR) and respiratory rate (RR) 2 h after operation in Groups C and D were significantly lower than those in Groups A and B (P < 0.05). The pain scores decreased over time after treatment in all groups. When compared at the same time point, children in Group D had the lowest pain scores, which were significantly lower than the other three groups (P < 0.05). The total consumption of sufentanil in Groups C and D was significantly lower than that in Group A (P < 0.05). On the first day after surgery, the children in Group D had lower levels of serum adrenocorticotropic hormone, interleukin-6, and corticosterone than those in Group A (P < 0.05).

Conclusion

Administration of 1.0 µg/kg/day of dexmedetomidine combined with sufentanil in intravenous controlled analgesia after Salter osteotomy for developmental hip dislocation in children has a better analgesic effect, less consumption of sufentanil, and low incidence of opioid adverse reactions.

Outcomes following medial open reduction in infants aged ≤6 months with developmental dysplasia of the hip

Aim

To evaluate mid-long term radiological outcomes following early medial approach open reduction (MAOR) performed for developmental dysplasia of the hip (DDH) in infants aged ≤6 months old at time of surgery, specifically incidence of clinically significant avascular necrosis (AVN), Severin outcomes and rates of further surgery.

Methods

This is a single centre retrospective study of patients treated from 1999 to 2017. Only infants aged ≤6 months old at time of MAOR, and aged at least 6 years old at latest follow-up were included (minimum 5.5 years follow-up). Data was collected from electronic healthcare records and serial radiographs reviewed to assess outcomes. AVN was classified according to Kalamchi and MacEwen, with types 2-4 considered clinically significant. Severin classes I (excellent) and II (good) were considered satisfactory outcomes, and classes III + considered unsatisfactory.

Results

MAOR was performed on 48 hips in 44 patients. Mean age at time of surgery was 4 months (SD 1.4, range 2-6), with mean follow-up of 9.8 years (SD 2.7, range 6.2-16.2). Clinically significant AVN developed in 9/48 hips (19 %), all of which were type 2. Only 1/48 hips (2 %) required a subsequent pelvic osteotomy due to residual dysplasia with subluxation at 2 years post MAOR. At final follow-up, 81 % of patients had excellent or good radiological outcomes (Severin I/II). No statistically significant predictors for developing AVN, including age and presence of ossific nucleus, were identified.

Conclusion

Early MAOR in infants aged ≤6 months was associated with a very low rate of significant residual dysplasia requiring further surgery, yet was not associated with unacceptable rates or severe forms of AVN. We therefore recommend MAOR is performed early to optimise acetabular remodelling potential and minimise the need for concurrent or subsequent bony procedures.

MicroRNA-34a-5p promotes the progression of osteoarthritis secondary to developmental dysplasia of the hip by restraining SESN2-induced autophagy

Osteoarthritis (OA), a late-stage complication of developmental dysplasia of the hip (DDH), is a key factor leading to further degeneration of joint function. Studies have shown that Sestrin2 (SESN2) is a positive regulator in protecting articular cartilage from degradation. However, the regulatory effects of SESN2 on DDH-OA and its upstream regulators remain obscure. Here, we first identified that the expression of SESN2 significantly decreased in the cartilage of DDH-OA samples, with an expression trend negatively correlated with OA severity. Using RNA sequencing, we identified that the upregulation of miR-34a-5p may be an important factor for the decrease in SESN2 expression. Further exploring the regulation mechanism of miR-34a-5p/SESN2 is of great significance for understanding the mechanism of DDH occurrence and development. Mechanistically, we showed that miR-34a-5p could significantly inhibit the expression of SESN2, thereby promoting the activity of the mTOR signaling pathway. We also found that miR-34a-5p significantly inhibited SESN2-induced autophagy, thereby suppressing the proliferation and migration of chondrocytes. We further validated that knocking down miR-34a-5p in vivo resulted in a significant increase in SESN2 expression and autophagy activity in DDH-OA cartilage. Our study suggests that miR-34a-5p is a negative regulator of DDH-OA, and may provide a new target for the prevention of DDH-OA.

Defining the Incidence of Residual Acetabular Dysplasia After Successful Reduction With a Harness

BACKGROUND

The purpose of this study was to evaluate the rate of residual acetabular dysplasia (RAD), defined as an acetabular index (AI) of >90th percentile of age and sex-matched controls, in a cohort of infants successfully treated with the Pavlik harness (PH).

METHODS

We retrospectively studied typically developing infants at a single center, with at least 1 dislocated hip, that was successfully treated with a PH and had a minimum of 48 months follow-up. Hip dislocation was defined as <30% femoral head coverage at rest on pretreatment ultrasound or IHDI grade 3 or 4 on the pretreatment radiograph.

RESULTS

Forty-six dislocated hips (41 infants) were studied (4 males and 37 females). Brace treatment was initiated at an average age of 1.8 months (range: 2 d to 9.3 mo) and was maintained for an average of 10.2 months (range: 2.3 to 24.9 mo). All hips achieved IHDI grade 1 reduction. Five of 46 hips (11%) had an AI >90th percentile at the conclusion of bracing. Average follow-up was 6.5 years (range: 4.0 to 15.2 y). We found a 30% incidence of RAD (14/46 hips) on final follow-up radiographs. Of these hips, 13/14 (93%) had AI <90th percentile at the end of brace treatment. Comparing children with and without RAD, there were no differences in age at the initial visit or brace initiation, total follow-up, femoral head coverage at the initial visit, alpha angle at the initial visit, or total time in the brace (P > 0.09).

CONCLUSION

In a single-center cohort of infants with dislocated hips treated successfully with a PH, we observed a 30% incidence of RAD at a minimum 4.0-year follow-up. Normal acetabular morphology at the end of brace treatment did not result in normal acetabular morphology at the final follow-up in 13/41 hips (32%). We recommend that surgeons should pay close attention to the year-over-year change in both the AI and AI percentile.

LEVEL OF EVIDENCE

Level IV: case series.

The natural history of acetabular dysplasia and later total hip arthroplasty in late-detected DDH: 48 patients with closed reduction followed to a mean age of 62 years

BACKGROUND AND PURPOSE

The long-term prognosis of acetabular dysplasia without subluxation in developmental dislocation of the hip (DDH) is uncertain. The aim of this study was to assess the consequence of having acetabular dysplasia at skeletal maturity on the need for having a total hip arthroplasty (THA) up to the age of 60 years.

PATIENTS AND METHODS

Inclusion criteria were age at diagnosis 0.5-3.0 years, initial treatment with skin traction to obtain closed reduction during 1958-1962, and no acetabular procedures to improve femoral head coverage. 48 patients (57 hips) met these criteria, 41 girls and 7 boys. Hip dysplasia was defined as a center-edge (CE) angle at skeletal maturity of 10-19°, and hips with CE angles in the range 20-25° were termed borderline dysplastic.

RESULTS

At skeletal maturity, 18 hips had acetabular dysplasia with a mean CE angle of 15.8° (10-19), whereas 19 hips were borderline with CE angles 20-25°, and 20 hips were normal (CE angles ≥ 26°). During the follow-up period 16 hips had undergone THA, 11 of 18 hips with dysplasia, 4 of 19 with borderline dysplasia, and 1 of 20 hips without dysplasia (p < 0.001). Hip survival in the 18 dysplastic hips, with THA as the endpoint, was 100% up to patient age 40 years; thereafter survival fell to 83% at 50 years and 39% at 60 years. There was no significant correlation between CE angle at skeletal maturity and age at THA (p = 0.2). The mean age at the last follow-up in patients without THA was 62 years (60-64).

CONCLUSION

Acetabular dysplasia without subluxation was a risk factor for THA, but less than one-fifth of the hips had undergone THA up to patient age 50 years.

Transient inferior over-reduction after open reduction in walking-age DDH: A retrospective analysis of 42 Hips

Background

Due to various policy and health infrastructure issues, it is not uncommon to present developmental dysplasia of hip(DDH) at walking-age in India. The purpose of this study was retrospective analysis of operated cases of walking-age DDH with "inferior over-reduction".

Methods

"Inferior over-reduction" was defined as break in the Shenton's arc inferiorly in an operated hip which otherwise appears reduced. After Ethical Committee approval, we searched children operated for walking-age DDH. Children suggestive of syndromic association were excluded. We collected demographic data, follow-up, procedures performed, inferior over-reduction and complications. The IHDI grade, Acetabular Index(AI), Smith's ratio for superior (h/b) & lateral displacement(c/b) of femur, and clinical outcome (Modified McKay criteria) were evaluated. The outcomes of cases with inferior over-reduction(Group A) were compared with those without(Group B).

Results

42 patients with average follow-up of 23 months were enrolled. 21 hips belonged to Group A. By 6 months follow up, all these cases recovered. On comparison of Smith's ratio, group A had significantly higher c/b for the operated hip at 3-month follow-up(p < 0.05). Patients undergoing acetabuloplasty had significantly lower c/b versus all other groups(p < 0.05). Correlation between h/b or c/b with age did not show any significant finding. 15 cases in group A and 14 cases in group B had excellent outcome as per modified McKay's criteria. None of the patients had inferior over-reduction, inferior or obturator dislocation at final follow-up. Three patients with group B had re-dislocation with poor outcome. we recorded 3 hips with AVN (7%).

Conclusions

This study highlights that after OR of walking-age DDH, the inferior over-reduction may be noted in as much as 50% of the cases. However, this is transient, and all cases recover by the 6 months follow up. There is no significant difference between group A & B in functional outcome, AVN rate. Long-term studies are required to see outcome differences between two groups.