Aims. To determine the likelihood of achieving a successful closed reduction (CR) of a dislocated hip in developmental dysplasia of the hip (DDH) after failed Pavlik harness treatment We report the rate of avascular necrosis (AVN) and the need for further surgical procedures. Methods. Data was obtained from the Northern Ireland DDH database. All children who underwent an attempted closed reduction between 2011 and 2016 were identified. Children with a dislocated hip that failed Pavlik harness treatment were included in the study. Successful closed reduction was defined as a hip that reduced in theatre and remained reduced. Most recent imaging was assessed for the presence of AVN using the Kalamchi and MacEwen classification. Results. There were 644 dislocated hips in 543 patients initially treated in Pavlik harness. In all, 67 hips failed Pavlik harness treatment and proceeded to arthrogram (CR) under general anaesthetic at an average age of 180 days. The number of hips that were deemed reduced in theatre was 46 of the 67 (69%). A total of 11 hips re-dislocated and underwent open reduction, giving a true successful CR rate of 52%. For the total cohort of 67 hips that went to theatre for arthrogram and attempted CR, five (7%) developed clinically significant AVN at an average follow-up of four years and one month, while none of the 35 hips whose reduction was truly successful developed clinically significant AVN. Conclusion. The likelihood of a successful closed reduction of a dislocated hip in the Northern Ireland population, which has failed Pavlik harness treatment, is 52% with a clinically significant AVN rate of 7%. As such, we continue to advocate closed reduction under general anaesthetic for the hip that has failed Pavlik harness. Cite this article: Bone Jt Open 2021;2(8):594–598

Aims. Various surgical techniques have been described for total hip arthroplasty (THA) in patients with Crowe type III dislocated hips, who have a large acetabular bone defect. The aim of this study was to evaluate the long-term clinical results of patients in whom anatomical reconstruction of the acetabulum was performed using a cemented acetabular component and autologous bone graft from the femoral neck. Methods. A total of 22 patients with Crowe type III dislocated hips underwent 28 THAs using bone graft from the femoral neck between 1979 and 2000. A Charnley cemented acetabular component was placed at the level of the true acetabulum after preparation with bone grafting. All patients were female with a mean age at the time of surgery of 54 years (35 to 68). A total of 18 patients (21 THAs) were followed for a mean of 27.2 years (20 to 33) after the operation. Results. Radiographs immediately after surgery showed a mean vertical distance from the centre of the hip to the teardrop line of 21.5 mm (SD 3.3; 14.5 to 30.7) and a mean cover of the acetabular component by bone graft of 46% (SD 6%; 32% to 60%). All bone grafts united without collapse, and only three acetabular components loosened. The rate of survival of the acetabular component with mechanical loosening or revision as the endpoint was 86.4% at 25 years after surgery. Conclusion. The technique of using autologous bone graft from the femoral neck and placing a cemented acetabular component in the true acetabulum can provide good long-term outcomes in patients with Crowe type III dislocated hips. Cite this article: Bone Joint J 2021;103-B(2):299–304

Large studies have reported high dislocation rates (7 to 24%) following revision total hip arthroplasty (THA), particularly when the revision is undertaken in the presence of pre-existing instability. We retrospectively reviewed the clinical and radiographic outcome of 155 consecutive revision THA's that had been performed using an unconstrained dual-mobility acetabular implant. It features a mobile polyethylene liner articulating with both the prosthesis head and a metal acetabular cup, such that the liner acts as the femoral head in extreme positions. It can be implanted in either a press fit or cemented manner. Mean follow-up was 40 months (18–66) and average age 77 (42–89). Uncemented (n=122) and cemented (n=33) implants with a reinforcing cage, were used. Indications were aseptic loosening (n=113), recurrent instability (n=29), periprosthetic fracture (n=11) and sepsis (n=2). Three of the 155 cases (1.9%) dislocated within 6 weeks of surgery and were successfully managed with closed reduction. The 3 dislocations occurred in the groups revised for recurrent dislocation and periprosthetic fracture. There were no cases of recurrent dislocation and no revisions for implant failure. Despite a pantheon of options available, post-operative dislocation remains a challenge especially in patients with risk factors for instability. The use of large diameter heads is proven to improve stability but there are concerns regarding wear rates, metal toxicity and recurrent dislocation in the presence of abductor dysfunction. With constrained liners there are concerns regarding device failure and aseptic loosening due to implant overload. Our dislocation rates of 1.9% and survivorship to date compare favourably with alternative techniques and are also in line with studies from France using implants of a similar design. In our hands, where there are risk factors for dislocation, the use of a dual-mobility implant has been very effective at both restoring and maintaining stability in patients undergoing revision THA.

The Pavlik harness (PH) is commonly used to treat infantile dislocated hips. Variability exists in the duration of brace treatment after successful reduction of the dislocated hip. In this study we evaluate the effect of prescribed time in brace on acetabular index (AI) at two years of age using a prospective, international, multicenter database. We retrospectively studied prospectively enrolled infants with at least one dislocated hip that were initially treated with a PH and had a recorded AI at two-year follow-up. Subjects were treated at one of two institutions. Institution 1 used the PH until they observed normal radiographic acetabular development. Institution 2 followed a structured 12-week brace treatment protocol. Hip dislocation was defined as less than 30% femoral head coverage at rest on the pre-treatment ultrasound or IHDI grade III or IV on the pre-treatment radiograph. Fifty-three hips met our inclusion criteria. Hips from Institution 1 were treated with a brace 3x longer than hips from institution 2 (adjusted mean 8.9±1.3 months vs 2.6±0.2 months)(p < 0 .001). Institution 1 had an 88% success rate and institution 2 had an 85% success rate at achieving hip reduction (p=0.735). At 2-year follow-up, we observed no significant difference in AI between Institution 1 (adjusted mean 25.6±0.9˚) compared to Institution 2 (adjusted mean 23.5±0.8˚) (p=0.1). However, 19% of patients from Institution 1 and 44% of patients from Institution 2 were at or below the 50th percentile of previously published age- and sex- matched AI normal data (p=0.049). Also, 27% (7/26) of hips from Institution 1 had significant acetabular dysplasia, compared to a 22% (6/27) from Institution 2 (p=0.691). We found no correlation between age at initiation of bracing and AI at 2-year follow-up (p=0.071). Our findings suggest that prolonged brace treatment does not result in improved acetabular index at age two years. Hips treated at Institution 1 had the same AI at age two years as hips treated at Institution 2, while spending about 1/3 the amount of time in a brace. We recommend close follow-up for all children treated for dislocated hips, as ~1/4 of infants had acetabular index measurements at or above the 90th percentile of normal. Continued follow-up of this prospective cohort will be critical to determine how many children require acetabular procedures during childhood. The PH brace can successfully treat dislocated infant hips, however, prolonged brace treatment was not found to result in improved acetabular development at two-year follow-up

Extensive and severe bone loss of the femur may be a result of a failed total hip arthroplasty (THA) or total knee arthroplasty (TKA) with multiple revision surgeries which may be caused by factors such as infection, periprosthetic fracture or osteolysis. The aim of this study was to assess outcomes of using the “Push-Through Total Femoral Prosthesis” (PTTF) for revision of a total hip replacement with extreme bone loss. Fourteen patients who had extensive bone defects of the femur due to failed THR's and were treated with PTTF between 2012 and 2020 were included in this study. Primary functional outcomes were assessed using Harris Hip Score (HHS), Toronto Extremity Salvage Score (TESS) and Musculoskeletal Tumor Society (MSTS) scores. Range of motion, complications, and ambulatory status were also recorded to assess secondary outcomes. Two of 14 patients underwent surgery with PTTF for both knee and hip arthroplasty revision. The mean time between index surgery and PTTF was 15 years (3 to 32 yrs.). Acetabular components were revised in six of 14 patients. After a mean follow-up of 5.9 years, hip dislocations occurred in 3 patients. All dislocated hips were in patients with retained non-constrained acetabular bearings. Patient satisfaction was high (MSTS: 67%, HHS: 61.2%, TESS 64.6%) despite a high re-operation rate and minor postoperative problems. PTTF is a unique alternative that may be considered for a failed THA revision procedure in patients with an extreme femoral bone defect. Patients are able to ambulate pain free relatively well. Routine usage of constrained liners should be considered to avoid hip dislocation which was our main problem following the procedure

Background. Postoperative dislocation is one of the main surgical complications and the primary cause for revision surgery after 2-stage implant exchange due to periprosthetic infection of a total hip arthroplasty. Objective. The aims of our study were (1) to determine the incidence of dislocation after two-stage THA reimplantation without spacer placement, (2) to evaluate relevant risk factors for dislocation and (3) to assess the final functional outcome of those patients. Method. We prospectively analyzed 187 patients who underwent a two-stage total hip arthroplasty (THA) revision after being diagnosed with periprosthetic joint infection (PJI) from 2013 to 2019. The mean duration of follow-up was 54.2 ± 24.9 months (>36 months). The incidence of postoperative dislocation and subsequent revision was estimated through Kaplan-Meier curves and potential risk factors were identified using Cox hazard regression. The functional outcome of the patients was assessed using the modified Harris Hip Score (mHHS). Results. The estimated cumulative dislocation-free survival was 87.2% (95% CI: 81.2%-91.3%) with an estimated 10% and 12% risk for dislocation within the first 6 and 12 months, respectively. The use of a dual-mobility construct had no significant impact on the dislocation rate. Increasing body mass index (BMI) (HR=1.11, 95% CI: 1.02-1.19, p=0.011), abductor mechanism impairment (HR=2.85, 95% CI: 1.01-8.01, p=0.047), the extent of elongation of the affected extremity between stages (HR=1.04, 95% CI: 1.01-1.07, p=0.017), the final leg length discrepancy (HR=1.04, 95% CI: 1.01-1.08, p=0.018) and PJI recurrence (HR=2.76, 95% CI: 1.00-7.62, p=0.049) were found to be significant risk factors for dislocation. Overall revision rates were 17% after THA reimplantation. Dislocated hips were 62% more likely to undergo re-revision surgery (p<0.001, Log-rank= 78.05). A significant average increase of 30 points in mHHS scores after second-stage reimplantation (p=0.001, Wilcoxon-rank) was recorded, but no difference was noted in the final HHS measurements between stable and dislocated hips. Conclusion. Dislocation rates after 2-stage THA reimplantation for PJI remain high, especially regarding overweight or re-infected patients. Careful leg length restoration and an intact abductor mechanism seem critical to ensure stability in these complex patients

There is no consensus regarding the optimum frequency of ultrasound for monitoring the response to Pavlik harness (PH) treatment in developmental dysplasia of hip (DDH). The purpose of our study was to determine if a limited-frequency hip ultrasound (USS) assessment in children undergoing PH treatment for DDH had an adverse effect on treatment outcomes when compared to traditional comprehensive ultrasound monitoring. This study was a single-center non-inferiority randomized controlled trial. Children aged less than six months of age with dislocated, dislocatable and stable dysplastic hips undergoing a standardized treatment program with a PH were randomized, once stability had been achieved, to our current standard USS monitoring protocol (every clinic visit) or to a limited-frequency ultrasound protocol (USS only until hip stability and then end of treatment). Groups were compared based on alpha angle at the end of treatment, acetabular indices (AI) and IHDI grade on follow up radiographs at one-year post harness and complication rates. The premise was that if there were no differences in these outcomes, either protocol could be deemed safe and effective. One hundred patients were recruited to the study; after exclusions, 42 patients completed the standard protocol (SP) and 36 completed the limited protocol (LP). There was no significant difference between the mean age between both groups at follow up x-ray (SP: 17.8 months; LP: 16.6 months; p=0.26). There was no difference between the groups in mean alpha angle at the end of treatment (SP: 69°; LP: 68.1°: p=0.25). There was no significant difference in the mean right AI at follow up (SP: 23.1°; LP: 22.0°; p=0.26), nor on the left (SP:23.3°; LP 22.8°; p=0.59). All hips in both groups were IHDI grade 1 at follow up. The only complication was one femoral nerve palsy in the SP group. In addition, the LP group underwent a 60% reduction in USS use once stable. We found that once dysplastic or dislocated hips were reduced and stable on USS, a limited- frequency ultrasound protocol was not associated with an inferior complication or radiographic outcome profile compared to a standardized PH treatment pathway. Our study supports reducing the frequency of ultrasound assessment during PH treatment of hip dysplasia. Minimizing the need for expensive, time-consuming and in-person health care interventions is critical to reducing health care costs, improving patient experience and assists the move to remote care. Removing the need for USS assessment at every PH check will expand care to centers where USS is not routinely available and will facilitate the establishment of virtual care clinics where clinical examination may be performed remotely

Purpose. There is concern that the positive predictive value (PPV) of neonatal screening for instability may have deteriorated over recent years, this study aims to evaluate this. Method. This is a prospective observational longitudinal study from 2012 – 2016. Patients that were referred from paediatric neonatal screening with hip instability (Ortolani / Barlow positive, clunks) were identified and underwent ultrasound and clinical examination in the one stop hip clinic by the senior author. Referrals were taken from a range of screeners from paediatric doctors to midwives and advanced neonatal practitioners. Syndromic or neurological dislocated hips were excluded. The outcome measures were the presence of a subluxated / dislocated hip on ultrasound as per Graf and Harcke classification and a positive provocative manoeuvre on examination. This allowed a PPV to be evaluated for both ultrasound and clinical examination. Results. 139 neonates were referred for a suspected dislocated or dislocatable hip from paediatric screening services. These were seen at a mean 14.0 days (95% C I, 12.28 to 15.72). 20 patients had a Graf type 4 hip on ultrasound and 5 had a positive provocative test on examination. This represents an ultrasound PPV of 14.4% and clinical exam PPV of 3.6% . This has deteriorated from 15 year data from our unit (PPV 24% clinical, 49% sonographic). Our overall surgical rate for DDH has increased to 1.07 per 1000, and our overall rate of open reductions has increased to 0.7 per 1000. This is based upon figures from 2012 – 2014. Conclusion. The PPV of screening has decreased over the last 5 years. The concern is too many screeners who, with regards screening the paediatric hip, are poorly trained, inexperienced, not adequately supervised. We need to learn the lessons of Sweden and ensure better quality screening by limiting screening to a small number of experienced practitioners

Introduction and Objective. Despite pure alumina have shown excellent long-term results in patients undergoing total hip arthroplasty (THA), alumina matrix composites (AMCs) composed of alumina and zirconium oxide are more commonly used. There are no comparative studies between these two different ceramics. We performed a retrospective case-control study to compare results and associated complications between AMC from two manufacturers and those with pure alumina from another manufacturer. Materials and Methods. 480 uncemented THAs with ceramic on ceramic (CoC) bearing surfaces (288 men and 192 women; mean age of 54.1 ± 12.4 years), were implanted from 2010 to 2015. Group 1: 281 THAs with pure alumina; Group 2A: 142 with AMC bearing in a trabecular titanium cup. Group 2B: 57 hips with AMC bearing with a porous-coated cup. Results. The mean follow-up was 7.3 years. There was one late infection in group 1, eight dislocations, three in group 1 (1.1%), three in group 2A (2.1%), all with a 36 mm femoral head, and two in group 2C (3.5%). Liner malseating was found in one hip in group 1, and in five hips in group 2C, of these, there were four liner fractures (7.0%). Four cups were revised for iliopsoas impingement (three in group 1 and one in group 2B). Two cups were revised for aseptic loosening, one in group 1 and one in group 2A, and four revised femoral stems in group 2A, three for subsidence and another for postoperative periprosthetic B. 2. fracture. The mean preoperative Harris Hip Score was 48.6 ± 3.3 in the whole series and 93.9 ± 7.2 at the end of follow-up. The survival rate of revision for any cause was 98.2% (95% Confidence Interval: 96.6–99.8) at ten years for group 1, 95.8% (95% CI: 92.1–99.5) for group 2A, and 91.1% (95% CI: 83.7–98.5) for group 2B (log-rank 0.030). Conclusions. Outcome of uncemented CoC THA in young patients was satisfactory at mid-term in all three groups. However, liner fractures were frequent in group 2B. All dislocated hips in group 2A had a 36 mm femoral head diameter, and revision due to any cause was less frequent in group 1. Pure alumina CoC THA can be used as a benchmark for comparison with newer CoC THAs

Securing the osteotomized greater trochanter (GT) during total hip arthroplasty (THA) for dislocated dysplastic hips (DDH) poses a significant challenge. This study evaluates the union rate and effectiveness of a 2-strand transverse wiring technique utilizing the lesser trochanter for wire anchorage and tensioning. A digastric anterior slide trochanteric osteotomy was performed in 106 patients (118 hips) undergoing THA for DDH. Following uncemented stem insertion, the GT was transferred and fixed to the lateral cortex of the proximal femur using monofilament stainless steel wires. In 72 out of 106 patients (80 hips), the GT was fixed with 2 transverse wire cerclages threaded through 2 drill holes in the base of the lesser trochanter, spaced vertically 5–10 millimeters apart. The wires were wrapped transversely over the GT and tightened, avoiding contact with its tendinous attachments. Patients were regularly monitored, and GT union was assessed clinically and radiographically. Patient ages ranged from 20 to 57 years (mean 35.5), with a follow-up period ranging from 1.5 to 12 years (mean 6.2). The mean union time was 3.3 months (range 2–7). Among all hips, two developed stable nonunion and single wire breakage, but no fragment displacement (2.5%). Two hips exhibited delayed union, eventually healing at 6 and 7 months after surgery. Reattachment of the greater trochanter utilizing a 2-strand transverse wire cerclage anchored at the base of the lesser trochanter demonstrated a high rate of union (97.5%) following THA in dislocated DDH cases

Instability and aseptic loosening are the two main complications after revision total hip arthroplasty (rTHA). Dual-mobility (DM) cups were shown to counteract implant instability during rTHA. To our knowledge, no study evaluated the 10-year outcomes of rTHA using DM cups, cemented into a metal reinforcement ring, in cases of severe acetabular bone loss. We hypothesized that using a DM cup cemented into a metal ring is a reliable technique for rTHA at 10 years, with few revisions for acetabular loosening and/or instability. This is a retrospective study of 77 rTHA cases with severe acetabular bone loss (Paprosky ≥ 2C) treated exclusively with a DM cup (NOVAE STICK; SERF, DÉCINES-CHARPIEU, FRANCE) cemented into a cage (Kerboull cross, Burch-Schneider, or ARM rings). Clinical scores and radiological assessments were performed preoperatively and at the last follow-up. The main endpoints were revision surgery for aseptic loosening or recurring dislocation. With a mean follow-up of 10.7 years [2.1-16.2], 3 patients were reoperated because of aseptic acetabular loosening (3.9%) at 9.6 years [7-12]. Seven patients (9.45%) dislocated their hip implant, only 1 suffered from chronic instability (1.3%). Cup survivorship was 96.1% at 10 years. No sign of progressive radiolucent lines were found and bone graft integration was satisfactory for 91% of the patients. The use of a DM cup cemented into a metal ring during rTHA with complex acetabular bone loss was associated with low revision rates for either acetabular loosening or chronic instability at 10 years. That's why we also recommend DM cup for all high risk of dislocation situations

This technique is a novel superior based muscle sparing approach. Acetabular reaming in all hip approaches requires femoral retraction. This technique is performed through a hole in the lateral femoral cortex without the need to retract the femur. A 5 mm hole is drilled in the lateral femur using a jig attached to the broach handle, similar to a femoral nail. Specialised instruments have been developed, including a broach with a hole going through it at the angle of the neck of the prosthesis, to allow the rotation of the reaming rod whilst protecting the femur. A special C-arm is used to push on the reaming basket. The angle of the acetabulum is directly related to the position of the broach inside the femoral canal and the position of the leg. A specialised instrument allows changing of offset and length without dislocating the hip during trialling. Some instrumentation has been used in surgery but ongoing cadaver work is being performed for proof of concept. The ability to ream through the femur has been proven during surgery. The potential risk to the bone has been assessed using finite analysis as minimal. The stress levels for any diameter maintained within a safety factor >4 compared to the ultimate tensile strength of cortical bone. The described technique allows for transfemoral acetabular reaming without retraction of the femur. It is minimally invasive and simple, requiring minimal assistance. We are incorporating use with a universal robot system as well as developing an electromagnetic navigation system. Assessment of the accuracy of these significantly cheaper systems is ongoing but promising. This approach is as minimally invasive as is possible, safe, requires minimal assistance and has a number of other potential advantages with addition of other new navigation and simple robotic attachments

Introduction. Total hip arthroplasty (THA) for a highly dislocated hip can be problematic and technically challenging. Our previous study on cemented THA with subtrochanteric femoral shortening osteotomy revealed a high incidence (20%) of non-union. Therefore, in 2008, we introduced reverse hybrid THA using S-ROM stem for the treatment of a highly dislocated hip. The purpose of this study was to assess the short-term clinical outcomes of this new method. Patients and methods. Between 2008 and 2014, 13 consecutive reverse hybrid THAs were performed on nine female patients with highly dislocated hips. The average age at the time of operation was 66 years (range, 55–85 years). The acetabular component was fixed in the true acetabulum with bone cement. Transverse osteotomy was performed below the lesser trochanter to shorten the femur and to prevent over-lengthening. The proximal sleeve of the S-ROM stem was then fixed within the proximal fragment, and the distal fin provided rotational stability of the distal fragment. Thus, the two fragments were fixed to each other with the S-ROM stem, and the resected segment was longitudinally cut for grafting at the junction. The postoperative follow-up period was an average of 4 years (range, 1–7 years), and no patients were lost. Preoperative and final Japanese Orthopaedic Association (JOA) hip score, operation time, bleeding amount, intraoperative and postoperative complications, bone healing at the osteotomy site, implant loosening, and revision surgery were retrospectively investigated. Results. The mean JOA hip score improved from 56 points preoperatively to 82 points postoperatively. The operation time and amount of bleeding were an average of 208 min and 643 g, respectively. The mean length of femoral resection was 4 cm (range, 2–6 cm), and the tip of the greater trochanter migrated an average distance of 7 cm (range, 5–9 cm) distally. The calculated limb lengthening was an average of 3 cm (range, 2–4 cm). Intraoperative fracture was seen in two patients, but no repeat operation was required. Two patients experienced postoperative dislocation in their hips, but additional surgery was not necessary. Postoperative nerve palsy did not occur in any patient, and all the osteotomy sites showed complete bone union. There was no implant loosening seen in any patient, and there was also no need for revision surgery. Discussion and conclusions. To achieve satisfactory outcomes with this method, resection of necessary and sufficient length of femur and accomplishment of adequate fixation between the proximal and distal fragments are necessary. In this study, dislocation occurred in two patients, and no nerve palsy was seen. Larger femoral heads may be recommended to eradicate dislocations. In cases where metaphysis of the femur is hypoplastic or the medullary canal is wide, reaming and stem insertion should be carefully performed. In this series, no additional surgery was required for the intra- and post-operative complications, and the osteotomy sites achieved bone union in all patients. Therefore, we recommend the use of this method, although longer follow-up periods are necessary

In the case of a complete dislocated hip or a severe deformity of the proximal femur, total hip arthroplasty (THA) can still be combined with a proximal femoral osteotomy for shortening femur or correcting the deformity if needed. Subtrochanteric femoral shortening and a corrective osteotomy are considered to be an integral part of THA for such cases. A precise osteotomy is mandatory to achieve good results. Although, the freehand excision of V-shaped subtrochanteric osteotomy used to be performed frequently, this procedure was also subject to some pitfalls, such as poor coaptation of the osteotomy surface. A new device was thus developed to perform a V-shaped osteotomy in an identical central axis between the distal and proximal femur. The purpose of this study was to evaluate the efficacy of the device by comparing the perioperative results with those of a free-hand subtrochanteric osteotomy. From 1999 to 2002, THA combined with a double-chevron subtrochanteric osteotomy was performed by free hand (free hand group). From 2003 to 2007, THA combined with a double-chevron subtrochanteric osteotomy was performed using a new device (device group). The free hand group included 27 hips in 21 patients. The mean age of the patients (23 females and 3 males) at the time of the operation was 58 years. Fourteen were completely dislocated hips and 13 followed various proximal femoral osteotomies. The device group included 102 hips in 79 patients. The mean age of thepatients (70 females and 9 males) at the time of the operation was 62 years. Seventy two were completely dislocated hips and 26 followed various proximal femoral osteotomies. Four parameters were used to evaluate the efficacy of the device:. operation time,. total blood loss,. C-reactive protein at postoperative 1 day and. early complications at the osteotomy site. The mean operation time, total blood loss, and C-reactive protein in the device group all significantly decreased in comparison to the free hand group. The decreases ranged from; 132 to 96 minutes (p< 0.01), 1346 to 999 g (p< 0.01), 4.9 to 3.0 mg/dl (p< 0.05), respectively. Two types of complications were observed at the osteotomy site. Pseudoarthrosis at the osteotomy site was observed one case in each group and both of these cases underwent a stem revision (4% in the freehand group and 1% in the device group). A femoral shaft split was observed in 3 cases in the freehand group (11%) and 3 cases in the device group (3%) and all 6 cases were treated conservatively. There were no instances of nerve palsy, infections, or thromboembolic events resulting from these procedures. The above described new device allowed for the easy and accurate performance of a subtrochanteric V-shaped osteotomy with THA for either a completely dislocated hip or a severely deformed proximal femur

Purpose. To determine the effect of the femoral head ossific nucleus on the development of avascular necrosis (AVN) after reduction of a dislocated hip. We included consecutive patients treated for a dislocated hip secondary to DDH with either closed or open reduction under the age of 30 months (mean, 9.6□4.8) in this retrospective cohort study. 85 patients or 100 hips were included. Radiographs were analysed for the presence of the ossific nucleus at the time of hip reduction, and for the presence of AVN at 9.2□3.4 years after hip reduction by 3 blinded assessors. There was no significant effect of the femoral head ossific nucleus on the development of osteonecrosis, with 16/40 (40%) cases of osteonecrosis in infants with an ossific nucleus absent compared with 18/60 (30%) in the group with an ossific nucleus (adjusted relative risk = 0.83; 95% CI = 0.38 to 1.83; p=0.65). When only radiographic changes of grade II or worse were considered osteonecrosis, the association remained statistically insignificant (adjusted relative risk = 0.84; 95% CI = 0.35 to 2.00; p=0.69). Conclusion. Our study reports the longest follow-up addressing the question of a potential protective effect of the ossific nucleus on the development of AVN. We could not demonstrate such an effect. Strategies aimed at delaying the treatment of a dislocated hip in the absence of the ossific nucleus cannot be recommended as they will not affect the risk for subsequent AVN

Europeam Group of Neuro-orthopaedic (GLAENeO), Caracas, The prevention of a dislocated hip is one of the aims of early surgery in Cerebral Palsy children, specially those severely involved. We performed a retrospective study of those cerebral palsy patients operated of adductor tenotomy between 1975 and 1995 with a total of 1474 patients. We grouped them in those who had a unilateral tenotomy and those who had a bilateral tenotomy as primary surgery. Of these only 8% had an obturator neurectomy, without walking ability, and 92 % had it not. Age at surgery varied from 6 months to 8 years of age with a mean of 4 years and 3 months. Group I: 792 patients (53.7 %) with unilateral adductor contracture, sustained a unilateral adductor tenotomy. Of these patients a total of 619 (78, 2 %) required a contralateral adductor tenotomy at a mean of 3 years and 6 months. Group II: 682 patients (46, 3 %) with bilateral adductor contracture that had a bilateral adductor tenotomy in one stage. Of the 792 patients that sustained a two stage adductor tenotomy, 123 (20%) presented a unilateral dislocated hip and of these 115 (93 %) occurred in the hip operated secondly at a mean of 1 year post tenotomy. Of the 682 patients with bilateral adductor tenotomies only 7 (1 %) had a dislocated hip 2 years post tenotomy. Of the 72 dislocated hips, 12 (59 %) were quadriplegics, 28 (22 %) were diplegic, 21 (18 %) hemiplegics and 1 (1 %) tetraplegic. Of the 619 patients tenotomized in two stages, in 143 the diaphyseal – cervical angle was 155 ° (23,1 %), at a mean of 6 and a half years of age and 3 years post the second tenotomy. In 102 of these patients (71 %) a varus derotation osteotomy was performed in the hip operated in the second act with further dislocation of the hip in 20 cases (20 %). Of the 685 patients with bilateral tenotomy in one stage, varus derotation osteotomy was required in 68 (68 %) at a mean of 6 years of age with only a 3 % of dislocations in this group. In view of these results we recommend a bilateral adductor tenotomy be performd regardless of a difference in the degree of contracture of both sides, thus coordinating the forces and avoid further dislocation the hip

Background. Several risk factors for the development of osteonecrosis following treatment of developmental dislocated hip have been reported. The need for further research with a large-enough sample size including statistical adjustment of confounders was demanded. The purpose of the present study was to find reliable predictors of osteonecrosis in patients managed for developmental dislocation of the hip. Methods. A retrospective cohort study of children, who have been hospitalized at our department between January 1998 and February 2007 with a developmental dislocation of the hip, was completed. Sixty-four patients satisfied the criteria for inclusion. Three groups according to age and treatment were identified. Group A and B included patients treated with closed or open reductions aged less than twelve months. Patients of group C were past walking age at the time of reduction and were treated by open reduction combined with concomitant pelvic and femoral osteotomies. The average duration of follow-up for all patients was 6.8 years. Logistic regression analysis was conducted to identify predictors for the development of osteonecrosis. Results. The overall rate of osteonecrosis in group A and B was 27.4% compared to 88.2% in patients of group C. After pooling of all data, no protective effect of the ossific nucleus of the femoral head on the development of osteonecrosis was found (p = 0.14). Additionally, an increase of surgical procedures in children of group C could not be demonstrated (p = 0.17). By using logistic regression analysis the type of reduction and secondary reconstructive procedure due to residual acetabular dysplasia could be identified as predictors for the development of osteonecrosis. Conclusions. Open reduction combined with concomitant osteotomies and secondary reconstructive interventions due to residual acetabular dysplasia increase the risk for osteonecrosis in the treatment of the developmental dislocated hip. Therefore, we advocate early reduction of the dislocated hip in the first year of life to avoid the need for concomitant osteotomies combined with open reduction. Level of Evidence. Prognostic study, level II-1 (retrospective study)

Hip displacement is the second most common deformity in children with cerebral palsy (CP). A displaced, and particularly a dislocated hip, can have significantly adverse effects on an individual. Surgical intervention to correct progressive hip displacement or dislocation is recommended for children with CP. Success of surgical intervention is often described using radiological outcomes. There is evidence that surgical treatment for displaced or dislocated hips decreases pain and hip stiffness and improves radiological outcomes. However, there is no information in the literature regarding the impact of surgical treatment on the health related quality of life (HRQOL) in these children. The aim of our study was to examine the impact of surgical treatment of hip displacement or dislocation on HRQOL in children with CP. This prospective longitudinal cohort study involved children attending a tertiary care hospital orthopaedic department. Children with CP between the ages of 4 and 18 years, with hip displacement/dislocation, defined as a Reimer's migration percentage (MP) of >40% on a pre-operative x-ray, and undergoing surgical reconstruction were eligible for inclusion. Quality of life was measured pre-operatively and post-operatively using the CPCHILD Questionnaire. Twelve patients (one child was GMFCS level III, 4 were level IV, and 7 were level V), aged 4.0 to 17.3 years, were assessed pre-operatively and then again at least six months post-operatively. All underwent unilateral (5) or bilateral (7) reconstructive hip surgery. The migration percentage of hips undergoing reconstruction was reduced by an average of 52% (9–100%). The average change in CPCHILD score showed an increase of 6.4 points [95% CI: −1.4–14.2]. In this pilot study, no significant change was noted in HRQOL following reconstructive hip surgery, despite a marked reduction in Reimer's MP. However, only 4 of 12 parents reported that their child had daily pain pre-operatively. A larger sample size will be required to draw more accurate conclusions from these findings. There is an evident need for a multicentre study examining this issue in a larger patient population in order to determine the long-term impact of different hip interventions on quality of life in children with CP

Objective. By retrospective analysis of clinical data, to find new risk factors for postoperative dislocation after total hip replacement and the dose-effect relationship when multiple factors work simultaneously. Methods. A nested case-control study was used to collect the dislocated hips from 5513 primary hip replacement case from 2000 to 2012. Apart from the patients with given cause of dislocation, 39 dislocated hips from 38 cases were compared with 78 hip from 78 cases free from dislocation postoperatively, which matched by the admission time. The factors that may affect the prosthetic unstable was found by the univariate analysis, and then they were performed multivariate logistic regression analysis and evaluation of a dose-effect factors. Results. The clinical scores between the two groups was no significant difference before and after surgery. Univariate analysis revealed the position of acetabular prosthesis (P = 0.05) and the big ball (P=0.01) differences were statistically significant. While patient with adduction deformity incorporating limb lengthening≧2cm(P<0.01) or the knee valgus deformity incorporating pelvic obliquity (P=0.01), as well as bilateral cases (P=0.02) were also the risk factors for dislocation. Big head decrease the dislocation rate. Multivariate analysis confirmed these newly founded factors are more important than the classic factors in this group of patients. Conclusion. Patients with hip adduction deformity combined with limb lengthening, knee valgus deformity combined with pelvic obliquity and bilateral pathological hip seem more predisposed to dislocation after total hip arthroplasty, who should be strengthened preoperative education and postoperative management to prevent. Key Word. total hip arthroplasty, dislocation, multivariate analysis

Laterality and bilaterality have been reported as prognostic variables in DDH outcomes. However, there is little clarity across the literature on the reporting of laterality in developmental dysplasia of the hip (DDH) due to the variability in severity of the condition. It is widely accepted that the left hip is most frequently affected; however, the true incidence of unilateral left, unilateral right and bilateral cases can be hard to quantify and compare across studies. The purpose of this study was to examine laterality accounting for graded severity in a multicentre, international prospective observational study of infants with hip dysplasia in order to demonstrate the complexity of this issue. A multicentre, prospective database of infants diagnosed with DDH between the ages of 0 and 18 months was analysed from 2010 to April 2015. Patients less than six months were enrolled in the study if at least one hip was frankly dislocated. Patients between 6 and 18 months were enrolled if they had any form of hip dysplasia. Each hip was classified as reduced, dysplastic, dislocatable/subluxable, dislocated reducible or dislocated irreducible. Baseline diagnosis was used to classify patients into a graded laterality category accounting for hip status within the DDH spectrum. A total of 496 patients were included in the analysis; 328 were <6 months old at diagnosis and 168 were between 6 and 18 months old. Of these patients, 421 had at least one frankly dislocated hip. Unilateral left hip dislocations were most common, with 223 patients, followed by unilateral right and bilateral dislocations with 106 and 92 respectively. Stratifying these patients based on status of the contralateral hip, 54 unilateral left and 31 unilateral right dislocated patients also had a dysplastic or unstable contralateral hip. There were significantly fewer bilateral patients in the 6–18 month group (p=0.0005). When classifying laterality by affected hip, bilaterality became the predominant finding, comprising 42% of all patients. The distribution of unilateral left, unilateral right and bilateral cases was greatly impacted by the method of classification. Distinct patterns were seen when considering dislocated hips only, or when considering both dislocated and dysplastic/unstable hips. Findings from this multicentre prospective study demonstrate the necessity to account for the graded severity in hip status when reporting DDH laterality. In order to accurately compare laterality across studies, a standardised, comprehensive classification should be established, as contralateral hip status may impact prognosis and treatment outcomes