Hip Dislocation In Patients Research Articles

Insufficient stem antetorsion and lower cup abduction is a combined risk factor for posterior hip dislocation in patients undergoing THA for femoral neck fractures: a retrospective analysis

BackgroundThe role of acetabular and femoral component positions with respect to the risk of post-operative instability and dislocation remains debated. In this study, we aimed to identify potential risk factors for early dislocation following primary total hip arthroplasty (THA) for displaced intracapsular femoral neck fractures (FNF) using radiological measurements.MethodsWe retrospectively analyzed data for patients who underwent cementless primary THA for FNF using a posterolateral approach between January 2018 and December 2021. Follow-up duration, age, sex, affected side, and mean time from THA to dislocation were recorded. Leg-length inequality, abductor lever arm, vertical and horizontal femoral offsets, vertical and horizontal hip centers of rotation, abduction, anteversion of the acetabulum and femoral prosthesis, and combined anteversion were measured.ResultsThe study sample included 17 men and 34 women, with 21 and 30 patients undergoing left- and right-hip operations, respectively. The mean patient age was 70.18 ± 7.64 years, and the mean follow-up duration was 27.73 ± 13.52 months. The mean time between THA and dislocation was 1.58 ± 0.79 months. Seven patients (13.73%) sustained posterior dislocation of the hip. The abduction angle (36.05 ± 6.82° vs. 45.68 ± 8.78°) (p = 0.008) and anteversion of the femoral prosthesis (8.26 ± 4.47° vs. 19.47 ± 9.01°) (p = 0.002) were significantly lower in the dislocation group than in the control group. There were no significant differences in other parameters.ConclusionsInsufficient stem antetorsion combined with lower abduction angle of the acetabular component were associated with a high risk of dislocation, especially in patients with deep flexion or internal rotation of the flexed hip joint and knees, or in patients with a stiff spine or anterior pelvic tilt, impingement may then occur in the neck of the prosthesis and cup component, ultimately resulting in posterior dislocation. These findings could remind surgeons to avoid simultaneous occurrence of both in THA surgery. These results provide new insight into risk factors for hip dislocation in patients undergoing primary THA for FNF and may aid in reducing the risk of instability and dislocation.Level of evidenceProspective comparative study Level II.

Does the limb lengthening reduce the incidence of hip dislocation in patients with neurological disorders and insufficient muscle tension who undergoing hip arthroplasty?

The soft-tissue tension is closely associated with postoperative hip dislocation in patients undergoing total hip arthroplasty (THA), especially for those patients with neurological disorders and insufficient muscle tension. The aim of this study is to explore the effect of limb lengthening on the incidence of complications following THA in patients with neurological disorders and insufficient muscle tension. This retrospective analysis examines individuals with neurological disorders, such as ischemic stroke and poliomyelitis, who underwent primary total hip arthroplasty (THA) at our medical center between January 2015 and April 2021. Demographic and baseline characteristics (such as age, gender, muscle strength) were obtained from medical records. The limb length, offset and the positional parameters of both acetabular and femoral component were measured on pre- and postoperative plain radiograph. The primary outcome was the occurrence of hip dislocation. The secondary outcome included the incidence of other complications and the hip function (determined by Harris score). The correlation between the occurrence of hip dislocation and limb lengthening was analyzed. A total of 258 patients were finally analyzed. The hip dislocations were identified in 35 patients (overall incidence = 13.57%). The incidence of early dislocation was lower in patients whose limb-length discrepancy (LLD) was over 20 mm (incidence = 4.1% for LLD >20 mm, 12.2% for LLD 10 mm-20 mm and 17% for LLD <10 mm). The odds ratio (OR) was 0.206 and 95% confidence interval (CI) was 0.058-0.737 (compared between LLD <10 mm and LLD >20 mm). But the no difference was identified regarding on the incidence of late dislocation among patients with different LLD. Moreover, the overall incidence of other complications was elevated in patients with LLD >20 mm (incidence = 17.58% for LLD >20 mm, 11.11% for LLD 10 mm-20 mm and 3.19% for LLD <10 mm; OR = 6.464, 95% CI = 1.768-23.640). And the Harris scores, which reflected the hip function, was gradually decreased with the increasing in LLD. In terms of the relationship between the offset and dislocation rate, it was found that increased offset discrepancy was associated with decreased dislocation incidence (incidence = 4.71% for offset discrepancy >10 mm, 12.5% for offset discrepancy 5 mm-10 mm and 17.20% for offset discrepancy <5 mm; OR = 0.238, 95% CI = 0.076-0.742). Furthermore, increased offset discrepancy also bring a reduction in late dislocation. The incidences of late dislocation were 0%, 2.5% and 10.8% for offset discrepancy >10 mm, offset discrepancy 5 mm-10 mm and 17.20% for offset discrepancy respectively. Different from that of LDD, the incidences of other complications were similar among patients with different offset discrepancy. Besides, no influence of offset discrepancy on the hip function was identified in this study. Unfortunately, although increasing in limb length could partially reduce early dislocation postoperatively, it could not affect the incidence of late dislocation in those patients with neurological disorders and insufficient muscle tension. Moreover, over limb lengthening was associated with other postoperative complications and worse hip function. Instead, additional offset could reduce the probability of postoperative dislocation, without increasing the incidence of other complications. Therefore, femoral stem with lower cervico-diaphyseal angle (higher offset) should be recommended to patients with neurological disorders who were in high risk of postoperative dislocation. Isolated increasing in limb length should be avoided.

Tranexamic Acid in Hip Reconstructions in Children with Cerebral Palsy: A Double-Blind Randomized Controlled Clinical Trial.

Surgical treatment is indicated for hip dislocation in patients with cerebral palsy (CP), but it requires care due to the state of nutrition and associated clinical comorbidities. The use of resources that minimize blood loss and the need for blood transfusions are essential to avoid complications. Tranexamic acid (TXA) has been highlighted for orthopedic surgeries to control intraoperative bleeding; however, there is a lack of large studies for its use in hip surgeries in patients with CP. This study aims to evaluate the efficacy and safety of tranexamic acid to reduce bleeding in pediatric patients with cerebral palsy undergoing surgical treatment for hip instability. A sample of 31 patients with CP who underwent surgical treatment for hip dislocation (hip adductor stretching, varization osteotomy of the proximal femur and acetabuloplasty using the Dega technique) was randomly divided into groups: control (n = 10) and TXA (n = 21). Preoperative and 24 h hemoglobin concentrations, the length of hospital stay (LHS), and intraoperative bleeding (IB) were analyzed. TXA significantly reduced the IB (p = 0.02). The variance in hemoglobin concentration was lower for the TXA group, but without statistical significance (p = 0.06). There was no difference in LHS. Also, no statistical difference was observed for the number of transfusions (p = 0.08). The findings provide evidence of the effectiveness of TXA in decreasing intraoperative bleeding and its safety for use in pediatric patients with cerebral palsy.

Skeletal maturity as a biomarker for determining indications for regenerative interventional technologies in adolescent patients with hip and knee diseases

Skeletal maturity as a biomarker for determining indications for regenerative interventional technologies in adolescent patients with hip and knee diseases

Effect of Botulinum Toxin Injection on the Progression of Hip Dislocation in Patients with Spastic Cerebral Palsy: A Pilot Study.

Hip adductor spasticity is a contributing factor to hip dislocation in patients with cerebral palsy (CP). We hypothesized that botulinum toxin injected into the hip adductor muscles would reduce spasticity and help prevent hip dislocation. Twenty patients with bilateral spastic CP aged 2 to 10 years with gross motor function classification system level IV or V were included. Botulinum toxin was injected into the hip adductor muscles at baseline and at 6-month follow-up. Muscle tone was measured with an eight-channel surface electromyography (EMG) recorder. A hip X-ray was performed, and Reimer’s hip migration index (MI) was measured. The Wilcoxon signed-rank test was used to compare the surface EMG values of the hip muscles at baseline and follow-up. The mean root mean square surface EMG value of the hip adductor muscles was significantly reduced at 1, 2, 3, and 7 months after the first injection, up to approximately 53% of the baseline. The 1-year progression of the hip MI was −0.04%. Repeated sessions of botulinum toxin injections at the hip adductor muscles significantly reduced muscle tone and hip displacement. A botulinum toxin injection may be used as an adjunctive treatment in the prevention of hip dislocation.

Does lumbar spine fusion predispose patients to future total hip replacement?

Hip-spine syndrome has been well studied since it was first described by Offierski and MacNab in 1983. Today, strong evidence links symptoms of hip and spine pathology to postsurgical outcomes. Recent studies have reported increased rates of hip dislocation in patients previously treated with total hip arthroplasty (THA) who had undergone lumbar fusion procedures. However, the effect of this link on native hip-joint degeneration remains an area of ongoing research. The purpose of this study was to characterize the relationship between use of lumbar fusion procedures and acceleration of hip pathology by analyzing the rate of future THA in patients with preexisting hip osteoarthritis. This population-level, retrospective cohort study was conducted by using the PearlDiver research program. The initial patient cohort was defined by the presence of diagnosis codes for hip osteoarthritis. Patients were categorized according to use of lumbar fusion after diagnosis of hip pathology. Survival curves with respect to THA were generated by comparison of the no lumbar fusion cohort with the lumbar fusion cohort. To assess the impact of fusion construct length, the lumbar fusion cohort was then stratified according to the number of levels treated (1-2, 3-7, or ≥ 8 levels). Hazard ratios (HRs) were then calculated for the risk factors of number of levels treated, patient age, and sex. A total of 2,275,683 patients matched the authors' inclusion criteria. Log-rank analysis showed no significant difference in the rates of THA over time between the no lumbar fusion cohort (2,239,946 patients) and lumbar fusion cohort (35,737 patients; p = 0.40). When patients were stratified according to number of levels treated, again no differences in the incidence rates of THA over the study period were determined (p = 0.30). Patients aged 70-74 years (HR 0.871, p < 0.001), 75-79 years (HR 0.733, p < 0.001), 80-84 years (HR 0.557, p < 0.001), and ≥ 85 years (HR = 0.275, p < 0.001) were less likely to undergo THA relative to the reference group (patients aged 65-69 years). Although lumbar fusion was initially hypothesized to have a significant effect on rate of THA, lumbar fusion was not associated with increased need for future THA in patients with preexisting hip osteoarthritis. Additionally, there was no relationship between fusion construct length and rate of THA. Although lumbar fusion reportedly increases the risk of hip dislocation in patients with prior THA, these data suggest that lumbar fusion may not clinically accelerate native hip degeneration.

Does timing of lumbar fusion affect dislocation rate after total hip arthroplasty?

IntroductionThe impact of lumbar spinal fusion (LSF) on pelvic mobility and increased risk for THA dislocation are recognized. However, there is still controversy on whether THA should be performed prior or following LSF. This study aims to compare the rates of hip dislocation in patients undergoing THA prior to or following LSF. MethodsWe retrospectively reviewed 109 primary THA and LSF. There were 34 men and 75 women with a mean age of 66.9. The cohort was divided into 2 groups: 1) THA prior to lumbar fusion (n = 42) and 2) THA following lumbar fusion (n = 67). Radiographic parameters including acetabular component abduction, anteversion, pelvic incidence (PI), sacral slope, standing lumbar lordosis (LL) and PI-LL mismatch were determined for each patient. The surgical approach and THA parameters were also recorded and compared between the 2 groups. Patients with fracture, malignant disease, and prior hip hardware were excluded. ResultsThe mean follow up was 14.7 months. Overall, 8 patients (7.3%) had a postoperative hip dislocation (0 in group 1 (0%), and 8 in group 2 (11.9%) (p = 0.022). The mean cup abduction and anteversion in patients that dislocated was 37.7° and 23.4° respectively while patients who did not dislocate had an average cup abduction of 37.6° (p = 0.970) and anteversion of 25.9° (p = 0.367). Patients who dislocated had decreased lumbar lordosis (p = 0.022) and higher PI-LL mismatch (p = 0.0004) compared to that did not dislocate. There were no other significant differences in the spinopelvic parameters between the 2 groups. Neither surgical approach nor dual mobility articulations use had a significant impact on postoperative dislocations. ConclusionHigher rates of hip dislocation were observed in patients undergoing primary THA following LSF. Dislocators had decreased lumbar lordosis and increased PI-LL mismatch. Patients who require both spinal fusion and THA should undergo hip arthroplasty first to minimize the risk of postoperative instability.

Surgical hip dislocation for treatment of synovial chondromatosis of the hip.

In the present study, we aimed to evaluate the clinical outcomes of surgical hip dislocation in patients with synovial chondromatosis (SC) of the hip. Seven patients with primary SC of the hip treated with open synovectomy and removal of loose bodies by surgical hip dislocation from 2016 to 2019 were retrospectively reviewed. All patients had numerous and widespread loose bodies based on pre-operative images, including routine radiographs, CT, and MRI. The visual analog scale (VAS) score and Harris hip score (HHS) were collected and analyzed before and after surgery. The post-operative radiographs were reviewed to evaluate disease recurrence and osteoarthritis progression. The mean operative time was 61 minutes(range, 42-75min). An average of 33 loose bodies in each patient (range, 16-67) was removed, and extra-articular pathology was found in one patient. Patients were followed up for a mean duration of 30months (range, 18-42months). The average VAS scores were decreased from 3.7 (range, 2-6) pre-operatively to 0.9 (range, 0-2) at the last follow-up, and the HHS was improved from 60.1 (range, 50-73) to 90.1 (range, 82-95). All results demonstrated significant improvements (P < 0.05). Post-operative radiographs showed no recurrence, osteoarthritis progression, or osteonecrosis of the femoral head in all hips. Surgical hip dislocation was a practical approach for managing both intra-articular and extra-articular pathologic lesions around the hip. It was an effective treatment for SC of the hip with short surgical time, good joint functions, a lower recurrence rate, and few complications.

Diagnosis and Management of Hip Dislocation in Patients with Kabuki Syndrome.

BackgroundKabuki syndrome is a rare genetic disorder characterized by distinct dysmorphic facial features, growth deficiency, intellectual disabilities, unusual dermatoglyphic patterns, and skeletal abnormalities. The incidence of hip dislocation in Kabuki syndrome ranges from 18% to 62%. We reviewed the outcomes of management of hip dislocations in patients with Kabuki syndrome with special attention to the diagnostic processes for hip dislocation and Kabuki syndrome.MethodsAmong 30 patients with mutation-confirmed Kabuki syndrome, we selected six patients who had hip dislocations and reviewed their medical records and plain radiographs. The modes of presentation and diagnostic processes for both hip dislocations and Kabuki syndrome were investigated. The management and treatment outcomes of hip dislocations in patients with Kabuki syndrome were evaluated.ResultsThe average age of patients at the time of diagnosis of hip dislocation was 7.7 months (range, 1 week to 22 months). None of the patients were diagnosed as having Kabuki syndrome at that time. Two patients were treated with a Pavlik harness; one, with closed reduction; two, with open reduction and later pelvic and/or femoral osteotomies; and one, with open reduction combined with pelvic osteotomy. The patients were followed up for 5.8 years on average (range, 2.0 to 10.5 years). The radiologic outcome was graded as Severin IA or IB for three patients who were older than 6 years at the latest follow-up (mean age, 9.9 years; range, 7.8 to 12.4 years). In the remaining three patients younger than 6 years (mean age, 3.8 years; range, 2.7 to 5.3 years), the lateral center edge angle was more than 15°. The clinical diagnosis of Kabuki syndrome was made during follow-up after hip dislocation treatment and confirmed by mutational analysis at a mean age of 4.7 years. The mean interval between the diagnosis of hip dislocation and Kabuki syndrome was 4.0 years.ConclusionsThe management of hip dislocation by conservative or surgical method showed successful results. Awareness of Kabuki syndrome could lead to an early diagnosis of this rare disease in patients with hip dislocation and allow for early detection of other underlying conditions and multidisciplinary management.

Total Hip Arthroplasty in Patients With Previous Lumbar Fusion Surgery: Are There More Dislocations and Revisions?

BackgroundThe purpose of this study was to determine whether the risk of dislocation and/or revision following THA is increased in patients with a history of prior lumbar fusion given the alterations in dynamic pelvic motion following LSF. MethodsA total of 62,387 patients (5% Medicare part B claims database) were identified from 1997 to 2014 with primary THA. From this group, 1809 patients (2.9%) were stratified to identify those with prior lumbar fusion within 5 years of primary THA to compare risk of dislocation and revision with those without lumbar fusion. Multivariate cox regression analysis was performed adjusting for age, socioeconomic status, race, census, region, gender, Charlson score, preexisting conditions, and type of fusion. ResultsBetween years 2002 and 2014, there was a 293% increase in the number of patients with prior lumbar fusion undergoing THA. Prevalence of hip dislocation in patients with lumbar fusion before THA was 7.4% compared to 4.8% without fusion, P < .001. There was an 80% increase in dislocation in the fusion group at 6 months, 71% at 1 year, and 60% at 2 years. There was a 48% increased risk of failure leading to revision hip surgery in patients with fusion at 6 months, 41% at 1 year, and 47% at 2 years. Dislocation was the most common mode of failure leading to revision in both the fusion group (20.8%) and the nonfusion group (16%). ConclusionResults of this study demonstrate that lumbar fusion before THA is an independent risk factor for dislocation leading to increased risk of revision THA.

Вывих бедра у подростков и взрослых, страдающих церебральным параличом: паллиативные методы оперативного лечения (обзор литературы)

The authors present a literature review related to surgical orthopedic treatment of hip dislocation in patients with severe cerebral palsy (GMFCS IV, V) in the age of 10 years and older. They discuss indications, special features, results, advantages and disadvantages of surgical interventions such as resection arthroplasty of the proximal femur, valgus support osteotomy of the femur, hip joint arthroplasty and arthrodesis.

The relationship between the level of lesion and progression in Reimer's index of spina bifida patients.

We aimed to evaluate the influence of the lesion level and acetabular displasia on the progression of hip dislocation in patients with spina bifida. Two hundred twelve hips of 106 cases with spina bifida were evaluated both clinically and radiologically. Their vertebral level of lesions, clinical examinations, radiological migration index, and acetabulum terms were noted and were evaluated in terms of their relations with the level of lesion-migration and dysplasia. Data analysis method was evaluated using SPSS 22.0 program. Deficiency of acetabulum was present in 33% of the cases with spina bifida. Dysplastic floor was found to be as equally important as the level of lesion in the progression of hip dislocation (p=0.002). Progression and dislocation incidences were observed to be higher in the thoracic level (p=0.008). Reimer's progression index was seen to be a reliable way of assesment. The development of hip dislocation and progression are not solely connected with muscle imbalance. Encountered more frequently in these cases, acetabular dysplasia is a factor that is as important as the level of lesion in the formation of hip dislocation and progression. Hip dislocation is associated with more progression in the higher level lesions. Reimer's index is a reliable assessment criteria.

Hip dislocation in cerebral palsy: evolution of the contralateral side after reconstructive surgery

ObjectiveTo evaluate the progression of the contralateral hip after unilateral reconstruction of hip dislocation in patients classified as GMFCS IV–V; and to identify potential prognostic factors for their evolution. MethodsThis was a retrospective study on 17 patients with spastic cerebral palsy, who were classified on the GMFCS scale (Gross Motor Functional Classification System) as degrees IV and V, and who underwent unilateral reconstruction surgery to treat hip dislocation (adductor release, femoral varus osteotomy and acetabuloplasty). The minimum postoperative follow-up was 30 months. The clinical parameters evaluated were sex, age at time of surgery, length of follow-up after surgery and range of abduction. The treatment parameters were use/nonuse of femoral shortening, application of botulinum toxin and any previous muscle releases. The radiographic parameters were Reimer's extrusion index (REI), acetabular angle (AA) and the continuity of Shenton's line. ResultsAmong the 17 patients evaluated, eight presented dislocation (group I) and nine did not (group II). Group I comprised three males and five females; group II comprised one male and eight females. The mean age at the time of surgery among the group I patients was 62 months and the mean follow-up was 62 months. In group II, these were 98 and 83 months, respectively. There was a trend in which patients of greater age did not evolve with contralateral dislocation. Among the nine patients with the combination of REI<30% and AA<25°, only one presented dislocation during the follow-up. Contralateral subluxation occurred within the first two years after the surgery. ConclusionHips presenting REI<30° and AA<25° do not tend to evolve to subluxation and can be kept under observation. Preoperative clinical and radiographic measurements alone are not useful for indicating the natural evolution of non- operated hips. The critical period for subluxation is the first two years after surgery.

Luxação do quadril na paralisia cerebral: a evolução do lado contralateral após cirurgia reconstrutiva

ObjectiveTo evaluate the progression of the contralateral hip after unilateral reconstruction of hip dislocation in patients classified as GMFCS IV–V; and to identify potential prognostic factors for their evolution. MethodsThis was a retrospective study on 17 patients with spastic cerebral palsy, who were classified on the GMFCS scale (Gross Motor Functional Classification System) as degrees IV and V, and who underwent unilateral reconstruction surgery to treat hip dislocation (adductor release, femoral varus osteotomy and acetabuloplasty). The minimum postoperative follow‐up was 30 months. The clinical parameters evaluated were sex, age at time of surgery, length of follow‐up after surgery and range of abduction. The treatment parameters were use/nonuse of femoral shortening, application of botulinum toxin and any previous muscle releases. The radiographic parameters were Reimer's extrusion index (REI), acetabular angle (AA) and the continuity of Shenton's line. ResultsAmong the 17 patients evaluated, eight presented dislocation (group I) and nine did not (group II). Group I comprised three males and five females; group II comprised one male and eight females. The mean age at the time of surgery among the group I patients was 62 months and the mean follow‐up was 62 months. In group II, these were 98 and 83 months, respectively. There was a trend in which patients of greater age did not evolve with contralateral dislocation. Among the nine patients with the combination of REI<30% and AA<25°, only one presented dislocation during the follow‐up. Contralateral subluxation occurred within the first two years after the surgery. ConclusionHips presenting REI<30° and AA<25° do not tend to evolve to subluxation and can be kept under observation. Preoperative clinical and radiographic measurements alone are not useful for indicating the natural evolution of non‐ operated hips. The critical period for subluxation is the first two years after surgery.

Are traumatic hip dislocations of the young and the elderly comparable: review of the literature from a recent case

Traumatic hip dislocation is a condition mostly encountered among young patients. However, clinical series reported regularly cases among elderly. From those, it seems that traumatic hip dislocation in young and elderly patients have a different profile. We present the case of a traumatic hip dislocation in a patient of 81 years secondary to a fall from his height. No fracture occurred. The dislocation was reduced by external maneuvers 3 h after the trauma. At last follow-up of 1 year, the patient developed a secondary hip osteoarthritis despite any articular incongruence. From a review of the literature, we found that epidemiology, pathophysiology, and prognosis of traumatic dislocation of the hip in the elderly may be different than those in young subjects. Hence, we suggest that the two conditions should be separated. Level of evidence: V. Expert opinion.

McHale Operation in Patients with Neglected Hip Dislocations: The Importance of Locking Plates

Neglected hip dislocation in patients with cerebral palsy is a challenge for the pediatric orthopedic surgeon. Many patients experience pain, limitation of hip motion, and sitting and hygiene problems. Arthrodesis, proximal femoral head resection, and subtrochanteric valgus osteotomy are effective salvage procedures for patients with painful hip dislocation and restricted hip motion when reconstruction of the hip is not possible. Osteopenia is one of the problems that can complicate the postoperative course in these patients. Postoperative cast immobilization may further worsen the osteopenia and can predispose to fractures of the femur after cast removal. Standard plating of the proximal osteotomy may not always provide adequate stability of the fixation. In order to prevent postoperative osteoporotic fractures we use locking plates, without casting. Since 2003 until 2011, we operated on 9 patients (14 hips) with painful neglected hip dislocations. The first three patients (five hips) were operated on using standard nonlocking plates. All other patients (nine hips) were operated on using locking plates. During the followup, the hardware failed in one of these cases. All patients treated with locking plates had not been casted postoperatively, and none had loss of fixation or fractures during the followup.

Epidemiology of traumatic hip dislocation in patients treated in Ceará, Brazil.

OBJECTIVE: To describe the epidemiological profile of patients with traumatic hip dislocation treated in our Institute from November/2012 to July/2013. METHODS: A descriptive cross-sectional study based on interviews and involving 43 patients who suffered traumatic hip dislocation was conducted. RESULTS: The mean age of patients was 34.4 years old and 90.7% were male. Regarding the mechanism of injury, 95% involved traffic accidents. The posterior dislocation of the hip was the most common injury (93%). Associated lesions were observed in 74.4% of patients, hip fractures being the most frequent. The time span between accident and dislocation reduction was less than 6 hours in 37.2% of patients, between 6 and 12 hours in 32.5% and over 12 hours in 30.3%, ranging from 1 hour to 15 days. A fraction of 90.7% of patients was submitted to closed reduction. CONCLUSION: Traumatic hip dislocation affected mostly young adults, victims of traffic accidents. The posterior dislocation of the hip was the most frequent injury and closed reduction was performed in 90.7% of patients. The time span between accident and dislocation reduction was less than 12 hours in most patients. Level of Evidence III, Study of Nonconsecutive Patients.

Letter to the Editor

To the editor, We read the study, “Femoroacetabular Impingement Predisposes to Traumatic Posterior Hip Dislocation” by Steppacher et al. [3] with great interest. As the authors mentioned, the proposal that femoroacetabular impingement could play a role in low-energy hip dislocations was suggested by Philippon et al. [2], based on the arthroscopic findings in professional athletes during active competition. There are scarce references reporting anatomic factors that predispose to posterior hip dislocation [4]. Steppacher and colleagues’ article proposed a mechanism of fulcrum by the interaction between the nonspherical femoral head and the acetabular rim in patients with femoroacetabular impingement-type CAM [3]. We were satisfied to read that the authors agreed with the mechanism that we recently described and represented graphically [1] in a case report of a young soccer player with femoroacetabular impingement that suffered from a low-energy posterior fracture-dislocation. In our publication, we also suggested other factors that could enhance posterior hip dislocation in patients with femoroacetabular impingement: retroversion of the femoral neck, retroversion of the acetabulum, and decreased acetabular depth. The study by Steppacher et al. [3] shows a higher prevalence of femoroacetabular features in patients with posterior hip dislocation compared with the normative data of the proposed mechanism. We believe posterior low-energy hip dislocation should not only be attributed to femoroacetabular impingement as an isolated mechanism. Further investigations should be performed to rule out the contributing factors in this entity.

Surgical treatment of hip dislocation in Kabuki syndrome: Use of incomplete periacetabular osteotomy for posterior acetabular wall deficiency

Kabuki syndrome is characterized by distinctive facial features, skeletal anomalies, persisting fingertip pads with dermatoglyphic abnormalities, postnatal growth deficiency and mental retardation. This report reviews our results in the operative treatment of hip dislocations in patients with Kabuki syndrome. Between 2001 and 2009, seven dislocated hips (three unilateral and two bilateral hips) in five patients (all girls) were operatively treated at our institution. The operative treatment consists of open reduction, femoral derotation varus osteotomy, pelvic osteotomy (Salter in one and incomplete periacetabular osteotomy in six hips) and capsular plication. The age of the patients at the time of surgery ranged from 2.4 to 5.7years, with an average of 3.6years. The follow-up postoperative period ranged from 3.2 to 6.3years, with an average of 5.0years. At the final follow-up, all patients reported no click and no pain, and showed well-contained hips by radiographs. All seven hips were graded as Severin class I-II. One patient presented as having habitual dislocation of the hip 4.4years after surgery. Computed tomographic (CT) scans revealed posterior acetabular wall deficiency, which was not corrected by the anterolaterally directed Salter osteotomy. The incomplete periacetabular osteotomy provided sufficient posterolateral coverage of the acetabulum. Operative treatment combining open reduction, femoral derotation varus and incomplete periacetabular osteotomies, and capsular plication provided successful results in patients with Kabuki syndrome who had the characteristics of hip instability such as ligamentous laxity, muscular hypotonia and posterior acetabular wall deficiency.

Rotational Acetabular Osteotomy for Habitual Hip Dislocation With Posterior Acetabular Wall Deficiency in Patients With Down Syndrome

Hip dislocation associated with Down syndrome is relatively rare. Hip dislocation can progress to severe subluxation or habitual dislocation if the initial therapy is improperly performed. However, definitive treatment guidelines for conservative and surgical therapy for hip dislocation in patients with Down syndrome have not been established. This article describes a case of a 12-year-old girl with Down syndrome with nontraumatic habitual hip dislocation. Her hip joint was associated with acetabular dysplasia and hypoplasia of the posterior acetabular wall. Although conservative therapy was initially performed, no effects were observed. Rotational acetabular osteotomy and capsular plication were performed to reconstruct the posterior acetabular wall. No postoperative redislocation occurred, and the treatment effects were favorably sustained for 2 years. In Down syndrome, few cases of developmental dysplasia and hypoplasia of the posterior acetabular wall have been reported. In previous reports, these morphological abnormalities were rarely taken into consideration when determining the treatment strategy, and to our knowledge, no other reports demonstrate therapy involving rotational acetabular osteotomy for hip dislocation complicated with Down syndrome. Whether the acetabulum had posterior wall deficiency was thought to be important for conservative and surgical therapies in hip dislocation in patients with Down syndrome. Rotational acetabular osteotomy could be an effective surgical procedure for reconstruction of the acetabulum by posterolateral rotation of the osteotomized acetabulum.