OBJECTIVE: Due to the technical challenges associated with femoral reconstruction in total hip arthroplasty for patients with developmental dysplasia of the hip (DDH), the exact indications for using femoral modular stems, despite their satisfactory clinical outcomes, remain poorly investigated. This study sought to assess the morphology of the femur and acetabulum, and to investigate the discriminative ability of femoral anteversion (FA), acetabular anteversion (AA), and combined anteversion (CA) on the selection of femoral modular stem in dysplastic hips.
METHODS: Retrospective data were collected from multiple centers on a total of 230 cases who underwent THA due to DDH from January 1, 2020, to March 1, 2023. There were 46 males and 184 females, with an average age of 51.57 ± 14.87. Patients were stratified according to Crowe and Eftekhar classifications. FA, AA, and CA were measured using computed tomography (CT). The distribution of these indices in different grades of dysplastic hips was compared, and the correlation between these indices and the selection of femoral modular stem was analyzed. Receiver operating characteristic (ROC) and likelihood statistics were performed to investigate the discriminating and predictive value of each index in selecting modular stem.
RESULTS: Two hundred and thirty hips were included in the study. FA increased as the subluxation percentage increased: type I, 21.5°; type II, 28.6°; type III, 34.9°; and type IV, 39.7°. AA was smaller in type I (16.9°) and higher in types II, III, and IV (18.9-22.6°). The area under the curve for the modular stem was 0.87 for FA, 0.86 for CA, and 0.65 for AA. The optimal cutoff values were FA > 32.6°, CA > 50.7°, and AA > 23.3°.
CONCLUSIONS: Excessive AA and femoral anteversion FA were observed in Crowe types II, III, and IV cases. FA and CA demonstrated strong discriminative ability and predictive value in the selection of a modular stem. The best cutoff values were ≥32.6° for FA and ≥50.7° for CA in discriminating the use of modular stem. Surgeons may contemplate the use of a modular stem when the preoperative evaluation approaches the cutoff value.

Developmental dysplasia of the hip (DDH) represents a complex spectrum of hip abnormalities, varying from mild dysplasia to severe dislocation, significantly impacting biomechanics and joint stability. This study explores the intricate pathogenesis of DDH, emphasizing its articular and periarticular anatomical anomalies and their profound implications. Factors such as breech positioning, advanced maternal age, postmaturity, and intrauterine crowding contribute to the complexity of DDH\'s etiology. The fetal development of the hip joint, crucial for understanding DDH, involves intricate processes starting from the fourth week of gestation. Any disruption during this period can lead to abnormal hip development, necessitating early detection and intervention. This is a case presentation of a four-year-old girl with bilateral DDH in detail, highlighting the clinical findings, diagnostic procedures, and physiotherapeutic management employed. A tailored physiotherapy plan was implemented, focusing on pain management, pressure sore prevention, respiratory care, and muscle strength preservation. This study highlights the need for further research in this area by illuminating the complexities of DDH. Despite difficulties and limitations in the literature, interest in researching different facets of DDH is expanding.

OBJECTIVE: To explore the clinical efficacy of high hip center technique total hip arthroplasty （THA） for Crowe Ⅱand Ⅲ developmental dysplasia of hip （DDH） and severe hip osteoarthritis （HOA）.
METHODS: From January 2018 to January 2020, 74 patients with Crowe typeⅡand Ⅲ DDH and severe HOA were admitted, and 37 cases of anatomical hip center reconstruction were taken as control group, including 7 males and 30 females, aged from 42 to 65 years old with an average of （58.40±4.98） years old, body mass index （BMI） ranged from 18 to 29 kg·m-2 with an average of （23.02±2.21） kg·m-2. Thirty-seven routine high hip center technical reconstruction were performed as study group, including 5 males and 32 females, aged from 41 to 65 years old with an average of （57.31±5.42） years old, BMI ranged from 18 to 29 kg·m-2 with an average of （23.14±2.07） kg·m-2. The patients presented with hip pain, limited function and range of motion, and gait instability before surgery. All patients underwent THA, the control group underwent intraoperative anatomical hip center reconstruction, and the study group underwent intraoperative high hip joint reconstruction. The perioperative indicators of the two groups were compared. The hip joint function, balance function and gait of the patients were evaluated before surgery, 3 months, 6 months, and 12 months after surgery. The length difference of both lower limbs, horizontal distance of rotation center, vertical distance of rotation center and femoral eccentricity were measured before operation and 1 year after operation. The incidence of complications in the two groups during the operation and postoperative follow-up was counted.
RESULTS: The operation time of the study group was shorter than that of the control group, and the intraoperative blood loss was less than that of the control group （P<0.05）. After 12-months follow-up, 1 was lost to followvup in study group and 2 were lost to follow-up in control group. The Harris scores and Berg balance scale（BBS）, pace, stride frequency and single step length in the study group were higher than those in the control group at 3 months and 6 months after operation （P<0.05）；there was no statistically significant difference between the two groups in the indexes 12 months after operation （P>0.05）. The vertical distance of the center of rotation of the study group was greater than that of the control group 12 months after operation （P<0.05）, and there was no significant difference in the length difference of the lower limbs, the horizontal distance of the center of rotation, and the femoral eccentricity between two groups （P>0.05）. There were no complications in either group.
CONCLUSIONS: The long-term effects of THA in patients with DDH and severe HOA were similar between the two central hip reconstruction methods, and the safety was good, and the high hip central reconstruction technique could shorten the operation time and reduce the amount of intraoperative blood loss.At the same time, it has certain advantages in early recovery of hip joint function, balance function and walking function of patients.

UNASSIGNED: There is no consensus in literature on the surgical treatment of patients with Crowe type III/IV patients. Each arthroplasty procedure has its own advantages and disadvantages. In this study by placing the acetabular cup between the true and false acetabulum, we aimed to share our experience about criteria of patient selection, surgical technique, and mid-term results of THA (total hip arthroplasty) in which the risk of dislocation was minimized using a standard-sized acetabular cup.
UNASSIGNED: We reviewed the clinical and radiographic data of the patients with Crowe type III/IV treated by cementless THA without femoral shortening osteotomy from January 2015 to January 2020. The clinical (Harris hip score, Trendelenburg sign, limb lengths) and radiographic (AP/L hip X-ray, 3D CT) examinations before surgery; 1, 3 months and 1 year after the surgery were evaluated. All postsurgical complications were noted.
UNASSIGNED: Among all, 268 patients met the inclusion criteria. Thirty-two patients (11.9%) were male and 236 (88.1%) were female. Mean age was 46.8 years. Mean follow-up duration was 42.4 (26-57) months. Mean Harris Hip score (HHS) was 49.7 and Trendelenburg sign was positive in all patients preoperatively. In the final evaluation, mean HHS significantly improved to 80.2 (p < 0.005) and none of the patients had Trendelenburg sign. Mean lengthening of the operated leg was 4.3 cm.
UNASSIGNED: Total hip arthroplasty with placement of acetabular cup between true and false acetabulum can be successfully preferred in selected patients with Crowe III/IV dysplasia.

Avascular necrosis (AVN) is a major morbidity that can occur after surgical reduction of a hip with developmental dysplasia. Early detection of changes in femoral head perfusion during surgery may help detect a hip at risk for AVN and guide intraoperative management. Contrast-enhanced ultrasound (CEUS) can be employed for visualization of femoral head perfusion. In this study we evaluate a quantitative CEUS technique to assess femoral head perfusion pre- and post-surgical reduction. CEUS images were obtained following a bolus injection of an ultrasound contrast agent, prior to and again following surgical reduction and casting. An image processing technique called delta projection was used to quantify hip perfusion, measuring peak enhancement (PE) and perfusion index (PI). We analyzed CEUS images of the hips of eight patients, including seven females, whose ages ranged from 4 months to 1 year. In five hips, perfusion increased following surgery, with a mean pre-surgery PE of 6.7 ±2.5(± SE) and PI of 10.5 ±6.3; and a post-reduction PE of 13.1±6.1 (p=0.07) and PI of 14.2 ±6.2 (p=0.008). The change in contrast visualization was observed to be greater within the central aspect of the cartilaginous femoral epiphysis. The proposed technique can quantify pre- and post-surgical perfusion changes on CEUS images in patients with developmental dysplasia. This quantitative technique may provide a more objective and accurate assessment of changes in femoral head perfusion that may have the potential to be indicative of the risk of developing AVN.

UNASSIGNED: Open reduction (OR) is usually required in developmental dysplasia of hip (DDH) for children below 24 months of age, those who failed to achieve a satisfactory reduction by the closed method. OR in this age group can be performed either through a medial or anterior approach. However, there is a paucity of literature and a lack of more substantial evidence regarding which approach (medial versus anterior) is superior for performing OR in this age group with minimal complications.
UNASSIGNED: Four databases (PubMed, Embase, Scopus, and Cochrane Library) were searched for relevant articles reporting outcomes and complication rates of DDH children less than 24 months undergone OR either through medial or anterior approach using pre-defined keywords. Data on avascular necrosis (AVN) rates, further corrective surgery (FCS) rates, and clinical and radiological grading using McKay clinical criteria and Severin radiological criteria were assessed. Meta-analysis was carried out using RevMan (Review Manager 5.4) software.
UNASSIGNED: Five comparative studies, having a minimum of two-year follow-up, were included for final analysis. According to the MINORS tool assessment, all five studies were of good to high quality. Of 257 hips, 151 and 106 underwent OR through medial and anterior approaches, respectively. Our meta-analysis showed a statistically significant (p = 0.01) number of AVN cases with the anterior approach compared to the medial approach. The overall random effect showed the odds of having AVN with an anterior approach to be 2.27 (95% CI: 1.18,4.38) times more than the same with a medial approach. Regarding FCS rates, the meta-analysis depicted no significant difference between the two groups (p = 0.63). The two groups had no statistically significant difference regarding clinical and radiological outcomes using McKay and Severin criteria, respectively. Following surgery, improvement in the acetabular index from pre-operative value showed no statistically significant difference between the two groups (p = 0.48).
UNASSIGNED: Medial approach is safe and effective for OR of the hip in DDH up to 24 months of age. Our analysis showed that AVN rates are lower with a medial approach than the anterior approach, with similar clinical and radiological outcomes and rates of FCS. However, one should consider the surgeon\'s expertise while choosing between these approaches.

UNASSIGNED: Developmental dysplasia of hip (DDH) is an abnormal development of hip joint which when neglected in early age group can lead to joint pain and secondary osteoarthritic changes. Crowe types III and IV neglected DDH joint is widely managed with total hip arthroplasty with subtrochanteric shortening.
UNASSIGNED: A 52-year-old female presented with neglected DDH joint which was managed in two stages with femoral lowering followed by uncemented total hip arthroplasty without osteotomy.
UNASSIGNED: With the two-stage procedure, subtrochanteric shortening which is widely accepted management for neglected DDH and the related complications were avoidable with a satisfactory Harris hip score.

Due to the change in the structure of the proximal femur and acetabulum in patients with developmental dysplasia of the hip, total hip arthroplasty (THA) was difficult to perform for surgeons. To elevate the acetabular coverage rate, we developed a technique in the use of a patient-specific instrumentation (PSI) graft in patients with developmental dysplasia of hip (DDH) undergoing surgery. This study aims to evaluate the peri-operative outcomes of THA with PSI graft in patients with DDH. This study recruited 6 patients suffering from Crowe I DDH with secondary Grade IV osteoarthritis. All the patients underwent THA with PSI graft performed by a well-experienced surgeon. Perioperative outcomes included surgical procedures, blood loss during operation, the volume of blood transfusion, length of hospitalization, complications, and the mean difference in hemoglobin levels before and after surgery. All the outcomes analyzed were assessed by mean and standard deviation. The average duration of the surgical procedure was found to be 221.17 min, with an SD of 19.65 min. The mean blood loss during the operation was 733.33 mL, with an SD of 355.90 mL. The mean length of hospital stay was calculated to be 6 days, with an SD of 0.89 days. Furthermore, the mean difference between the pre- and postoperative hemoglobin levels was 2.15, with an SD of 0.99. A total of three patients received 2 units of leukocyte-poor red blood cells (LPR) as an accepted blood transfusion. There were no reported complications observed during the admission and one month after the operation. This study reported the peri-operative outcomes in the patients with DDH who underwent THA with PSI graft. We found that THA with PSI graft would provide a safe procedure without significant complications. We assumed that the PSI graft in THA may increase the coverage rate of the acetabulum, which may increase the graft union rates. Further cohort studies and randomized controlled trials were needed to confirm our findings.

UNASSIGNED: It is very common for pediatric orthopedic surgeon to encounter developmental dysplasia of hip (DDH) in walking age, especially in developing countries. The conservative options of management are almost over by this age and most require open reduction (OR) with various adjunct procedures. The most preferred approach for OR in this age group is anterior Smith-Peterson approach to hip joint. These neglected cases also require femoral shortening ± derotation osteotomy and acetabuloplasty.
UNASSIGNED: In this surgical video technique, we demonstrate OR + femoral shortening and derotation osteotomy and acetabuloplasty, step by step, in a neglected, walking age DDH in a 3-year-old child. We hope that the detailed demonstration and tricks at various surgical steps will benefit our readers and viewers.
UNASSIGNED: Step-wise surgical execution as per demonstrated technique makes the procedure easily reproducible with fairly good outcomes. In this case example, with demonstrated surgical technique, we were able to achieve a good outcome at short-term follow-up.

This study aimed to investigate the relationship between acetabular width, three-dimensional (3D) simulation, and surgical results in total hip arthroplasty patients who have developmental dysplasia of the hip (DDH).
This retrospective study included 216 DDH cases. Inner and outer acetabular width (OAW) was measured at the plane passing through the center of acetabular fossa. 3D simulation and 2D standard templating were performed. The actual cup size and the use of augments during surgery were recorded. Association among the indices and their distribution in different types of DDH were analyzed.
A difference of 13 to 14 millimeters (mm) was found between the inner acetabular width and actual cup size used in type II, III, and IV cases, while the difference was 0.2 to 3.6 mm for OAW. The accuracy of 2D templating and 3D simulation in predicting cup size was comparable in Crowe type I (86.5 versus 76%, P = .075), type II (72.7 versus 51.5%, P = .127), and type III (93.3 versus 66.7%, P = .169). The 3D simulation was significantly more accurate in Crowe type IV (89.1% versus 60.9%, P = .001). Augments and bone grafts were significantly more commonly used in type II (25%) than in the other types (0 to 6.5%).
OAW more accurately predicted actual cup size than inner acetabular width. The supero-lateral acetabular bone defects in type II cases require additional attention. Compared with 2D templating, 3D simulation is more accurate in predicting actual cup size in dysplastic hips with severe deformity and may be recommended in these selected cases, especially for Crowe IV patients.