Background. Total hip arthroplasty for Crowe type IV developmental dysplasia of the hip is a technically demanding procedure. Restoration of the anatomical hip center frequently requires limb lengthening in excess of 4 cm and increases the risk of neurologic traction injury. However, it can be difficult to predict potential leg length change, especially in total hip arthroplasty for Crowe type IV developmental hip dysplasia. The purpose of the present study was to better define features that might aid in the preoperative prediction of leg length change in THAs with subtrochanteric femoral shortening osteotomy for Crowe type IV developmental dysplasia of the hip. Patients and Methods. Primary total hip arthroplasties with subtrochanteric femoral shortening osteotomy were performed in 70 hips for the treatment of Crowe type IV developmental hip dysplasia. The patients were subdivided into two groups with or without iliofemoral osteoarthritis. Leg length change after surgery was measured radiographically by subtracting the amount of resection of the femur from the amount of distraction of the greater trochanter. Preoperative passive hip motion was retrospectively reviewed from medical records and defined as either higher or lower motion groups. Results. The preoperative flexion of patients without iliofemoral osteoarthritis was significantly higher than for patients with iliofemoral osteoarthritis. All hips without iliofemoral OA had higher motion. The preoperative flexion in the higher motion group both with and without iliofemoral OA was significantly greater than in the lower group with iliofemoral OA (Figure 1). Leg length change in patients without iliofemoral osteoarthritis was significantly greater than with iliofemoral osteoarthritis (Figure 2), and the higher hip motion group had greater leg length change in THA than the lower motion group. No clinical evidence of postoperative neurologic injury was observed in patients with iliofemoral OA. Postoperative transient calf numbness in the distribution of the sciatic nerve was observed in 2 of 25 hips without iliofemoral OA (8.0%), however, no sensory and motor nerve deficit was observed. Discussion. The authors hypothesized that preoperative hip motion could affect soft tissue contractures, and our findings suggest that the soft tissues surrounding the hip joint with iliofemoral OA should be more contracted than the hip without OA. We also found leg length change in the higher motion group was greater than in the lower motion group. Previous studies reported limb lengthening in excess of 4 cm could increase the risk of nerve palsy. Transient calf numbness in the distribution of the sciatic nerve was observed in 2 hips without iliofemoral OA and their leg length change was not greater than 4 cm. Our findings suggest that hips without iliofemoral OA should be paid attention to protect the nerves from excessive elongation. The current study identifies several features that might help predict leg length change during the preoperative planning of total hip arthroplasty for Crowe type IV developmental hip dysplasia

Primary total hip arthroplasty in patients with osteoarthrosis secondary to developmental hip dysplasia is often more complex due to anterolateral acetabular bone deficiency. Femoral head (shelf) autograft provides a non-immunogenic, osteoconductive lateral support with the potential for enhanced bone stock should revision surgery be required. The technique has been shown in other series to give reliable early results but may be complicated by graft revascularisation and collapse. As yet, no study has assessed shelf grafts long term or quantified the need for further bone graft at revision surgery. This study aims to assess initial graft union rate; quantify long term graft resorption and; quantify the need for further bone graft in the patients requiring revision surgery. A retrospective analysis of a single surgeon's series of 31 THR in 25 patients was conducted. Post-operative, biplanar radiographic analysis was performed at 3 and 6 months and annually thereafter for a mean of 14 years (range 8-18). Grafts were assessed for union, resorption and displacement. Intra-operative necessity for bone graft at revision surgery was recorded. Union, osseous 93%, fibrous 7%. No grafts displaced. In 71% less than one-third of the graft resorbed, in 29% one-third to one-half resorbed and in no grafts did greater than a half resorb. Of 10 patients revised, 2 required bone graft for inadequate bone stock. Femoral head autograft allows effective acetabular coverage with excellent rates of union, minimal graft resorption in the long term and improves bone stock in revision surgery

Developmental dysplasia of the hip (DDH) refers to a spectrum of anatomical abnormalities. Despite various screening programs, delayed diagnosis still occurs. Delayed cases are more difficult to treat and can have poorer outcomes. Rural address, low socioeconomic status, and ethnicity have recently been associated with late presentation. The objectives of this study were to examine the incidence of DDH, as well as factors associated with delayed presentation in Saskatchewan.

Retrospective review of paediatric orthopaedic records from the tertiary referral centre in Saskatchewan was completed from 2008–2014. Variables collected included age at presentation, sex, birth order, birth presentation, birth complications, laterality, family history of DDH, postal code and treatment. Socioeconomic and geographic indicators were determined from postal code using the 2011 National Household Survey. Population level variables included income, ethnic origin, distance from referral centre and education. Associations were examined with bivariate and multivariate analysis.

There were 108 new presentations of DDH; 34 cases presented after age 3 months. Demographic data showed 83.3% of cases were female, 48.1% involved the left hip, 17.2% had a positive family history, 57.1% were first born, and 27.9% were breech. An estimated 5.6% of patients were Aboriginal. The mean age at presentation was 199.7 days. 48% of cases lived in the same city as the referral center. Late presenting cases lived on average 46.19 km farther from the referral centre and had a lower mean population, percent of adults with post-secondary education and income. However, none of these were statistically significant. No significant associations were found within the demographic data.

Overall incidence of DDH was not estimated due to few cases from southern areas of the province presenting to the tertiary referral center. The estimated incidence of DDH in the Aboriginal population from our sample was lower than previously reported in the literature. This association may be related to earlier swaddling practices, rather than Aboriginal ethnicity. There was a trend toward lower socioeconomic indicators and an increased distance from the referral centre in cases of late presentation, in keeping with recent literature exploring these factors. This suggests there may be deficits in the current selective screening protocols in North America. The study is limited by the retrospective nature of the research and the population level data obtained for certain variables. Future research to collect prospective individual level data may help elucidate important associations. Also, identifying any additional cases would increase the power to detect significant associations with late presentation, and allow an accurate estimate of overall incidence.

Developmental hip displasia (DHD) still presents as an important problem in our country. Latency in diagnosis and inaccurate treatment causes seconder osteoarthritis in young adults and elder patients. Variable reconstructive surgical procedures as proximal femoral and acetabular osteotomies can be performed, but the most satisfactory functional results are achieved by total hip arthroplasty (THA). In this study, we analyzed the results of the cementless total hip arthroplasties performed in coxarthrosis secondary to developmental hip displasia. Between January 2006 and October 2009, 53 patients diagnosed with hip osteoarthritis secondary to DHD, whom performed 59 total hip arthroplasties in GATA Orthopaedics and Traumatology Clinic were included in the study. 10 of the patients were male (%19), and 43 of them were female (%81). Age of the patients varied between 29 and 78 years and the mean age was 48,7. In 23 patients (%44), THA procedure was performed at the right hip and in 24 patients (%45) at the left hip. 6 patients operadted bilaterally. All patients were followed up 8–38 months (mean 20, 6 months) with clinical and radiological evaluation. The hospitalization period varied between 7–14 days, mean 8,3 days. Posterolateral incision was used at all of the patients. Totally 10 (%17) complications were observed. 5 (%8,5) of them was intraoperative and 5(%8,5) was postoperative. Patients evaluated preoperatively and postoperatively with modified Harris Hip Score. While preoperative mean Harris score was 39,1, the postoperative mean score measured as 90,3. The results were excellent in 52 cases (%88,1), and very good in 7 cases (%11,9). Appropriate implementation of cementless total hip prosthesis in patients with hip osteoarthritis secondary to DHD, who have good bone quality and surgical indicaton; clinical and radiological short term results were satisfactory.

Hypothesis

Successful total hip arthroplasty (THA) in the presence of developmental dysplasia of the hip (DDH) depends on restoration of the anatomic centre of hip rotation and may require simultaneous femoral osteotomy. Techniques using uncemented components are widely reported. In osteopenic bone an all-cemented technique may be more appropriate; however, the outcome following this procedure is not known. We present the results of a series of thirty-five cemented THA with simultaneous subtrochanteric osteotomy.

The management of developmental dysplasia of the hip (DDH) requiring open reduction between 12 and 18 months of age is controversial. We compare the outcome of medial approach open reduction (MAOR) versus delayed anterior open reduction with Salter osteotomy in such patients.

17 consecutive patients who underwent MAOR aged 12–20 months were reviewed (mean follow-up of 40 months, range 6–74). This group was compared to 15 controls who underwent anterior reduction and Salter osteotomy aged 18–23 months (mean follow-up of 44 months, range 14–134).

13 of the 17 (76%) MAOR patients required subsequent Salter osteotomy at a mean of 22 months post-reduction, with a further 2 patients under follow-up being likely to require one. Acetabular index improved from 42 (32–50, SD − 5.5) to 16 (7–24, SD − 4.5) in the MOAR group after Salter osteotomy compared to an improvement of 40 (30–53, SD − 6) to 13 (4–24, SD − 5) in the control group (p>0.05). Acetabular index at last follow-up was within normal limits in 15 of 17 (88%) MAOR patients. All patients in the control group had acetabular indices (or centre-edge angles of Wiberg) within the normal range.

There was 1 subluxation (7%) in the control group. There were 6 cases (33%) of post-operative avascular necrosis (5 Kalamchi & MacEwen Grade I, 1 Grade 2) in the MAOR group and 6 (40%) in the control group (5 Grade 1, 1 Grade 4).

All of the MAOR patients had good or excellent clinical results according to McKay's criteria, compared to 14 out of 15 (93%) controls.

This study suggests that MAOR or delayed open reduction and Salter osteotomy is a reasonable treatment for children with DDH presenting between the ages of 12 and 18 months. However, the majority of MAORs are likely to require a subsequent Salter osteotomy.

Developmental Dysplasia of the Hip (DDH) is the most common orthopaedic disorder in newborns. Whilst the Pavlik harness is one of the most frequently used treatments for DDH, there is immense variability in treatment parameters reported in the literature and in clinical practice, leading to difficulties in standardising teaching and comparing outcomes. In the absence of definitive quantitative evidence for the optimal Pavlik harness management strategy in DDH, we addressed this problem by scientifically obtaining international expert-based consensus on the same. An initial list of items relevant to Pavlik harness treatment was derived by systematic review of the literature according to PRISMA criteria and reviewed by two expert clinicians in DDH management. Delphi methodology was used to guide serial rounds of surveying and feedback to content matter experts from the International Hip Dysplasia Institute (IHDI), a collaborative group of paediatric orthopaedic surgeons with expertise in the management of DDH. Rounds of surveying continued in the same manner until consensus was reached. Importance ratings were derived from each round of surveying by calculating median score responses on the 5-point Likert scale for each item. Items requiring clarification or those with a median score of below 4 (“agree”) were modified as needed prior to each subsequent round. Consensus was considered reached when 90% or more of the items had an interquartile range (IQR) of ≤ 1. This value indicates low sample deviation and is accepted as having achieved consensus. This was followed by a corroboration of face validity to derive the final set of management principles. The literature search and expert review identified an initial list of 66 items in 8 categories relevant to Pavlik harness management. Four rounds of structured surveying were required to reach consensus. Following a final round of face validity, a definitive list of 33 items in 8 categories met consensus by the experts. These items were tabulated and presented as “General Principles of Pavlik Harness Treatment for DDH” and “Pavlik Harness Treatment by Severity of Hip Dysplasia”. Furthermore, highly contentious items were identified as important future areas of study and will be discussed. We have developed a comprehensive set of principles derived by expert consensus to assist clinicians, and for use as a teaching resource, in the non-operative management of DDH using the Pavlik harness. We have gained consensus on both the general principles of Pavlik harness treatment as well as the detailed treatment of hip subtypes seen across the spectrum of pathology of DDH. Furthermore, this study has also served to generate a list of the most controversial areas in the non-operative management of DDH which should be considered high priority for future study to further refine and optimise the outcomes of children with developmental hip dysplasia

Background. Total hip arthroplasty (THA) is a highly successful procedure, yet access to arthroplasty is limited in many developing nations. In response, organizations around the world have conducted service trips to provide international arthroplasty care to underserved populations. Little outcomes data are currently available related to these trips. We present a 1-year follow up. Methods. We completed an arthroplasty service trip to Brazil in 2017 where we performed 46 THAs on 38 patients. Patient demographic data, comorbidity profile, complication data, and pre- and postoperative Modified Harris Hip Score (mHHS), PROMIS Short Form Pain (SF-Pain), PROMIS Short Form Physical Function (SF-Function), and HOOS Jr scores were collected. Outcomes were collected postoperatively at 2, 6, and 12 weeks and 1 year. A multivariate regression analysis was performed to identify associations between patient factors and 12-week outcomes. Results. The mean patient age was 48.8 years. 47% were female. 30 patients had a unilateral THA and 8 had bilateral simultaneous THA (table 1). 61% of patients had a preoperative diagnosis of osteoarthritis (OA), 13% avascular necrosis, 13% post-traumatic OA, 8% developmental hip dysplasia, and 5% rheumatoid arthritis. Mean pain duration was 1–5 years for 45% of patients and >5 years for 55% of patients. The mean mHHS, HOOS, PROMIS SF-Pain and PROMIS SF-Function all improved significantly compared to baseline at 2, 6, 12 weeks and 1 year post-operatively (table 2, figure 1 & 2). At 1 year, only 11 of 38 patients (29%) were reachable by phone for follow up. The mobile phones were out of service for 27 of 38 patients (71%). Multivariate regression analysis did not reveal any associations at 12 weeks between patient reported outcomes and age, gender, pain duration, preoperative diagnosis or unilateral versus bilateral surgery (table 3). Conclusion. We found that patients in a developing country benefitted significantly from THA when performed by a visiting surgical team. Outcomes were similar to those seen in the United States. Of those that could be contacted, outcomes were stable at 1 year. This study highlights the difficulty of following patients in developing countries once they leave the hospital. Methods need to be developed to assure that the outcomes of these potentially valuable procedures can be determined. We are currently establishing the capability of using email and smart phone applications linked through email addresses to improve follow up on future missions

Introduction. Acetabular bone deficiency, especially proximal and lateral deficiency, is a difficult technical problem during primary total hip arthroplasty (THA) in developmental hip dysplasia (DDH). We report a configuration-based classification of hip, including a definition of shallow acetabulum. We also report a new reconstruction method using a medial reduced cemented socket and additional bulk bone in conjunction with impaction morselized bone grafting (Ad-BBG method). We aimed to evaluate usefulness of the classification and the method's clinical/radiographic outcomes. Methods. Forty percent of 330 THAs for DDH were defined as shallow dysplastic hips. The Ad-BBG method was performed on 102 hips (78% of shallow hips). For the 24 remaining hips, THA was performed using the conventional interposition bulk bone grafting (8 hips)or without bone grafting by using rigid lateral osteophyte (16 hips). Operative Technique: Theresected femoral head was sectioned at 1–2-cm thickness, and a suitable size of the bulk bone graft was placed on the lateral iliac cortex and fixed by polylactate absorbable screws. Autogenous impaction morselized bone grafting, with or without hydroxyapatite granules, was performed along with the implantation of medial reduced cemented socket. Radiographic criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone. The follow-up period was 10.2 ± 2.6 (range, 6.0–15.0) years. Results. Acetabular component was revised in only one case with a shallow and Crowe Type IV acetabulum. Within 2 years postoperatively, most Ad-BBGs cases showed successful bone remodeling and bone graft reorientation without collapse on radiographs. Discussion and Conclusions. Osteointegration and mid-term good clinical outcomes were achieved in acetabular reconstruction for primary THA using the medial reduced cemented socket and bone grafting methods including the Ad-BBG technique in conjunction with impaction morselized bone grafting for shallow dysplastic hip

Background. Total hip replacement is a highly successful procedure, yet access to arthroplasty is limited in many developing nations. In response, organizations in the United States have conducted service trips to provide international arthroplasty care to underserved populations. Little outcomes data are currently available related to these trips. We aimed to assess patient outcomes following total hip arthroplasty performed on a surgical mission trip. Methods. We completed an arthroplasty service trip to Brazil during which we performed 46 total hip arthroplasties (THA) on 38 patients. Patient demographic data, comorbidity profile, complication data, and pre- and postoperative Modified Harris Hip Score (mHHS), PROMIS Short Form Pain (SF-Pain), PROMIS Short Form Physical Function (SF-Function), and HOOS Jr scores were collected. Baseline and final follow-up scores were compared. In addition, we utilized a novel questionnaire that was designed to determine outcomes most relevant to patients receiving joint replacements in developing countries. A multivariate regression analysis was performed to identify associations between patient factors and outcomes. Results and Discussion. The mean patient age was 48.8 years, and 47% were female. 30 patients had a unilateral THA and 8 had bilateral simultaneous THA. 61% of patients had a preoperative diagnosis of osteoarthritis (OA), 13% avascular necrosis, 13% post-traumatic OA, 8% developmental hip dysplasia, and 5% rheumatoid arthritis. Mean pain duration was 1–5 years for 45% of patients and >5 years for 55% of patients. The mean mHHS, HOOS, PROMIS SF-Pain and PROMIS SF-Function all improved significantly compared to baseline at 2 and 6 weeks post-operatively. Multivariate regression analysis did not reveal any associations between patient reported outcomes and age, gender, pain duration, preoperative diagnosis or unilateral versus bilateral surgery. Subjective questionnaires at 12 weeks postoperatively revealed that surgery met expectations for 94% of patients; 97% of patients had as much pain relief as they expected; 45% of patients had no physical limitations; 82% of patients were not taking any medications for their hip (18% used occasional NSAIDs); 82% of patients gained new independence at home; and 97% felt their overall quality of life improved significantly. Two patients had postoperative periprosthetic femur fractures requiring an ORIF. One patient had a DVT requiring 6 months of anticoagulation. Conclusion. We found that patients in a developing country benefitted significantly from total hip arthroplasty when performed by a visiting surgical team, with acceptable complication profiles. Validated legacy outcome measures show improvements in pain and function after THA similar to those observed in patients in the United States. Additionally, the results of our questionnaire help to identify outcomes of specific interest to developing countries with relatively limited resources, particularly regaining functional independence after THA

Hip resurfacing offers an attractive alternative to conventional total hip arthroplasty in young active patients. It is particularly advantageous for bone preservation for future revisions. Articular Surface Replacement (ASR) is a hip resurfacing prosthesis manufactured by DePuy Orthopaedics Inc. (Warsaw, IN). The manufacturer voluntarily recalled the ASR system in 2010 after an increasing number of product failures. The present study aimed to determine the long-term results in a large cohort of patients who received the ASR prosthesis. Between February 2004 and August 2010, 592 consecutive hip resurfacings using the ASR (DePuy Orthopaedics Inc., Warsaw, IN) resurfacing implant were performed in 496 patients (391 males and 105 females). The mean age of the patients at the time of the surgery was 54 (range: 25 to 74) years. Osteoarthritis was the most common diagnosis in 575 hips (97.1%). The remaining patients (2.9%) developed secondary degenerative disease from ankylosing spondylitis, avascular necrosis, developmental hip dysplasia, and rheumatoid arthritis. Clinical and radiographic information was available for all patients at the last follow up. Cobalt (Co) and chromium (Cr) levels were measured in 265 patients (298 hips) by inductively coupled plasma-mass spectrometry (ICP-MS). The average follow up of the study was 8.6 years (range: 5.2 to 11.6 years). The mean Harris hip and UCLA scores significantly improved from 44 and 2 pre-operatively to 85.3 and 7.1 respectively. The median Co and Cr ion level was 3.81 microgram per liter and 2.15 microgram per liter respectively. Twenty-seven patients (5.4%) were found to have blood levels of both Co and Cr ions that were greater than 7 microgram per liter. Fifty-four patients (9.1%) were revised to a total hip arthroplasty. Kaplan-Meier survival analysis showed a survival rate of 87.1% at 8.6 years with revision for any cause and 87.9% if infection is removed. A significantly higher survival rate was observed for the male patients (90.2%, p <0.0001) and for the patients with ASRs with femoral heads diameters larger than 52 mm (90.1%, p=0.0003). This study confirms that patient selection criteria are of great importance to the overall survivorship of hip resurfacing arthroplasty. Improved clinical results have been reconfirmed with the use of larger diameter femoral heads

Introduction. Acetabular bone deficiency, especially proximal and lateral deficiency, is a difficult technical problem during primary total hip arthroplasty (THA) in developmental hip dysplasia (DDH). We report a configuration-based acetabular classification, a modification of the Crowe's classification, of DDH, including a definition of shallow acetabuli. We also report a new reconstruction method using a medial reduced cemented socket andadditional bulk bone in conjunction with impaction morselized bone grafting (Ad-BBG method). We aimed to evaluate usefulness of the classification and the method's clinical/radiographic outcomes. Methods. One hundred thirty one hips of 330 THAs for DDH (40%) were defined shallow. The Ad-BBG methodwas performed on 102 hips (78% shallow hips). For the 24 remaining hips, THA was performed using the conventional interposition bulk bone grafting (Ip-BBG) (8 hips)or without bone grafting by using rigid lateral osteophyte (16 hips). Japanese Orthopaedic Association (JOA) scores and the Merle d'Aubigne and Postel (M&P) scores were used in follow-up; radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone. The follow-up period was 9.2 ± 2.6 (range, 5.0–14.0) years. Operative Technique. Theresected femoral head was sectioned at 1–2-cm thickness, and a suitable size of the bulk bone graft was placed on the lateral iliac cortex and fixed by polylactate absorbable screws. Autogenous impaction morselized bone grafting, with or without hydroxyapatite granules, was performed along with the implantation of medial reduced cemented prosthetic hip socket. The same surgical team performed all surgical procedures. Results. Acetabular component was revised in only one case with a shallow and Crowe Type IV acetabulum. The mean JOA and M&P scores improved from preoperative 39.3 and 6.8 points to postoperative 93.9 and 17.2 points, respectively. Within 2 years postoperatively, most Ad-BBGs cases showed successful bone remodeling and bone graft reorientation on radiographs. Conclusions. We had good results of acetabular reconstruction in primary THA using the medial reduced cemented socket and bone grafting methods including the Ad-BBG technique in conjunction with impaction morselized bone grafting for shallow dysplastic hip. Osteointegration and good clinical outcomes were achieved in most cases. However, long-term outcomes should be subject of further investigation. Summary. Reconstruction methods for shallow dysplastic hip using medial reduced cemented socket and additional bulk bone grafting in conjunction with impaction morselized bone grafting are presented

Introduction. The project of a modular, double-conicity stem is born from the need to obtain primary stability and correct osseointegration in patients with developmental hip dysplasia, or proximal femoral dysmorphisms requiring a femoral shortening osteotomy or presenting characteristics of non-adaptability to single-conicity or straight stems. Such an implant could also be employed in femoral nail failures, or lateral femoral neck fractures requiring prosthetic substitution. Aim of the study. To assess implantability of the new double-conicity stem in cadaver femurs, determining “fit and fill” and the behaviour of femoral cortical bone by means of Rx, CT and pre- and post-implantation mechanical testing. Methods. Seven double-conicity stems with anti-rotation fins were implanted in cadaver femurs of various sizes. All femurs underwent pre- and post-implantation radiological assessment for evaluation of fit and fill at the 2 levels corresponding to the 2 conicities, fins penetration, possible microfractures and stem positioning. Prior to implantation, templating was carried out to define the correct size of the stem to be implanted. Modular necks with cervico-diaphyseal angle of 125° or 135° (short or long) were implanted, to preserve the correct rotation center and femoral offset. In 2 femurs, mechanical testing was performed before and after implantation, in order to assess, by means of strain gauges, the variation of the tensional state of cortical bone under dynamic loading (gait cycle simulation). In 2 femurs, 3 cm chevron shortening osteotomies were performed and stabilized with the stem alone. Results. Implanted stems respected pre-operative planning. In the 2 cases in which shortening osteotomies were performed, the stem allowed for good meta-diaphyseal stability without the employment of fixation devices. Radiographic assessment evidenced a valid “fit and fill”. In 4 cases the stem was correctly aligned; in 2 cases it was positioned in 1° varus and in 1 case in 1° valgus. In the 2 osteotomy cases, penetration of the fins was good at the proximal level and slight distally. In the remaining 4 cases penetration at both levels ranged from slight to good. No microfractures, either intraoperative or following stress testing, were evidenced. Mechanical tests showed that stem implantation reduced deformation of the femoral cortical bone undergoing cyclic loading, in comparison with the pre-implantation situation. Conclusions. The double-conicity prosthetic stem showed good implantability, with the capacity to allow for stability in case of femoral shortening osteotomies without the use of plates or cerclage fixation. Mechanical testing also showed a correct load distribution, and a reduction of stress on femoral cortical bone in comparison with the state before implantation. Prospective clinical studies are necessary to assess efficacy and dependability from a clinical and radiographic viewpoint

Hip osteoarthritis is prevalent in 8%–28% of patients with Down's Syndrome. Presence of disabling hip pain is increased along with prolonged life expectancy, suggesting total hip arthroplasty (THA). Seven consecutive patients (9 hips) with Down's syndrome had primary THA. Coxarthrosis was secondary to developmental hip dysplasia in 6 patients and slipped capital epiphysis in 1 patient. In 5 patients (7 hips) a previous hip surgery was performed. Average clinical and radiological follow up was 9.9 ± 6.4 years (range 2–22.5, median 9.3). Average age of patients at THA was 34.8 ± 7.5 years (range 25–47, median 35.4). In 2 patients (3 hips) a trochanteric slide was used for the surgical approach, while a lateral transgluteal approach was used in the remaining patients. One way ANOVA test was used to compare Harris Hip Scores (HHS) at post-operative follow-up. HHS improved significantly (p=0.008) improved from 4.1 ± 15.1 (range 18.5–65, median 45) to 84.3 ± 7.7 (range 70–93, median 85.8 at 4 year follow up. HHS (average 70.9 ± 6.2, range 66.5–80, median 68) remained essentially unchanged (p=0.43) at 8 year follow-up. Two patients required revision arthroplasty for stem loosening at 6 and 16 years post THA, respectively. The first patient is 7 years post revision and ambulates without aids. The second patient is 6.1 years post revision and ambulates with a walker. Six of the THAs required a constrained liner. No dislocations or deep infections were encountered. THA is reliable surgical intervention in patients with Down's Syndrome and symptomatic coxarthrosis

Total hip arthroplasty (THA) in teenagers is uncommon and previously associated with poor survival rates. However it is sometimes the only option remaining to relieve pain and improve function in patients with advanced hip disease. We report on the clinical and radiological outcomes of THA in teenage patients. Medical records and radiographs of all consecutive teenage patients undergoing THA at a tertiary referral centre between 2006–2011 were reviewed. Mean follow-up was 3.4 years (range 0.6–6.8) with 9 patients having at least 5 years follow-up. Post-operative Harris hip, Oxford hip (OHS) and University of California Los Angeles (UCLA) activity scores were recorded. 51 THAs were performed in 43 patients (21 male, 22 female) with a mean age of 17 years (range 12–19). The 5 most common indications were slipped upper femoral epiphysis osteonecrosis 15 (29.4%), developmental hip dysplasia osteonecrosis 5 (9.8%), multiple/spondylo-epiphyseal dysplasia 5 (9.8%), chemotherapy-induced osteonecrosis 4 (7.8%) and idiopathic osteonecrosis 4 (8.2%). 46 (90%) were uncemented THAs and 5 (10%) were reverse hybrid THAs with 7 computer assisted design/manufacture (CADCAM) femoral implants. Articular bearings were ceramic/ceramic in 40 (78.4%), metal/metal 6 (11.8%), metal/polyethylene 3 (5.9%) and ceramic/polyethylene 2 (3.9%). The survival rate was 96% with 2 acute head revisions for 1 sciatic nerve palsy and 1 instability. Other complications (8.2%) included 1 dislocation, 1 sciatic nerve palsy that resolved, 1 surgical site infection and 1 unexplained pain. At latest follow-up, the mean Harris hip score was 90 (68–99), OHS was 42 (32–48) and UCLA activity score was 6 (4–9). Radiological analysis showed 2 patients with lucent lines around the acetabular component, but no signs of osteolysis or wear. As one of the largest studies on teenagers undergoing THA, we report good clinical and radiological outcomes at short to intermediate term follow-up

Introduction. The published results of the use of a dual mobility cup to prevent instability in primary and revision total hip arthroplasty (THA) have established its efficacy. However, the monoblock, porous cobalt chromium cup design makes secure fixation difficult to achieve, limiting its use in patients with significant acetabular deformity or bone loss. Recently, a modular version of the dual mobility cup was introduced, consisting of a conventional porous shell with holes to allow augmented screw fixation, a highly polished modular metal liner, and a standard bipolar femoral head. The purpose of this report is to present its various indications, the surgical technique, and report our initial results. Methods. With IRB approval and FDA clearance, we implanted the modular dual mobility (MDM) cup in 15 patients undergoing primary and 5 patients undergoing revision THA deemed high risk for instability. Indications included septic and aseptic revision surgery, developmental hip dysplasia, avascular necrosis, recurrent dislocations, hemiarthroplasty conversion to THA, periprosthetic fracture, abductor insufficiency requiring augmented repair, and hypermobility from auto-immune inflammatory disease. Surgical Technique. The acetabulum is prepared in the standard fashion for implantation of a press-fit component. After implantation and possible screw augmentation, osteophytes are removed. A modular metal liner is manually inserted into the shell by lining up tines and then impacted into place. Concentric positioning must be confirmed. After standard femoral stem preparation, a dual-mobility head with multiple neck length options is easily assembled and placed on the trunion. The hip is then located and assessed for limb length, stability, and offset. Results. In the 15 primary THAs, successful implantation of the MDM construct was accomplished without issues related to the aforementioned technique. Adjunct screw fixation was utilized in 8 patients based on initial rim fit and bone quality. In all cases, the hip had to be manually dislocated because of increased stability. There were no peri-operative complications related to the MDM. In the 5 revision cases, insertion was possible in 4 of 5 patients. In 2 cases, the MDM liner was used in previously implanted, well-fixed and positioned metal acetabular shells compatible with the MDM insert. In 2 cases, the original metal cup was replaced with a shell compatible with the MDM insert. In the remaining patient, a failed hemi-resurfacing, the use of the MDM was abandoned because of impingement and excessive lengthening causing the inner trial head to disassociate from outer trial head. Discussion. The MDM cup offers a number of important features not available on the original dual mobility designs. These include the use of: 1) a conventional shell, inserted with familiar instrumentation; 2) a shell that can be used with either a highly cross-linked polyethylene liner or the modular polished metal liner; 3) conventional cancellous screws that makes possible augmented fixation in cases of significant bone loss or acetabular deformity. These features make possible the use of the dual mobility concept without the need to add to a hospital's cup inventory. The initial results in a variety of primary and revision conditions have been encouraging