Advanced-stage Osteoarthritis Research Articles

Increased serum ADAMTS-4 in knee osteoarthritis: a potential indicator for the diagnosis of osteoarthritis in early stages.

We compared serum levels of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4, ADAMTS-5, matrix metalloproteinase (MMP)-1, and MMP-3 in patients with different stages of knee osteoarthritis (OA), and investigated the clinical significance of diagnosing OA in early stages. OA patients were divided into 2 groups: early OA group (44 cases), intermediate and advanced OA group (26 cases). The healthy control group included 30 samples. ADAMTS-4, ADAMTS-5, MMP-1, and MMP-3 levels in the serum were tested using an enzyme-linked immunosorbent assay. A protein-protein interaction network was constructed by seeding the significantly expressed marker, followed by Gene Ontology enrichment analyses using Database for Annotation, Visualization and Integrated Discovery. ADAMTS-4 levels were significantly higher in patients at early stages of OA compared to intermediate or advanced OA and healthy controls. ADAMTS-5, MMP-1, and MMP-3 levels in intermediate and advanced-stage OA patients were significantly higher than those in early-stage OA patients and healthy controls. The protein-protein interaction network showed that ADAMTS-4 participates in 67 interactions. Gene Ontology enrichment analysis validated that genes associated with ADAMTS-4 participate in collagen metabolism and OA. ADAMTS-4 is a potential biomarker as an early diagnostic indicator of OA.

SAT0339 Virologic and Morphologic Evidences of Human Parvovirus B19 Infection in Osteoarthritis

BackgroundViral infections play a role in the pathogenesis of various forms of osteoarthritis (OA). The advanced stage of disease often manifests with severe inflammation and lesions of joint tissues related...

Editorial : Technology Advancement and Research Progress in Orthopedic Surgery

Undoubtefully, orthopedics is one of the most technical surgical specialities. Modern orthopedic surgery took shape in the process of making use of the advanced science and the latest technological achievments of the time. It was and, in some respect, still continues to be, a story of clinical driven discovery placed in the forefront of science by the inquiring minds of orthopedic surgeons, in their quest for answering stringent clinical demands. In the mid 1960s Charnley introduced the hip prosthesis and the use of bone cement for implant fixation, aiming to treat the pain and disability produced by cartilage deterioration in advanced stages of osteoarthritis [1]. Based on Chrnaley extensive knowledge and contibution in tribology, implant development was possible due flourishing metalurgy and polymer technology. Total joint replacement was than implemented and is continously refined today. Increasing surgeon expertise, follow up data gathered by means of national joint replacement registries as well as technological optimization are only few of the factors contributing to the wide spread of the procedure, Hard - hard friction couples, trabecular technology or biological coatings are continously improving the quality and lifetime of available prosthesis. Joint reconstructive surgery is nowadays the most succesful intervention in all times and all surgical specialities in terms of cost efficiency and patient satisfaction [2] In the middle 60s, when RW Jhonson and R.O Connor were taking the bulky video camera on their shoulder to inspect joints, it was an attempt to elucidate and document tricky cases of knee pathology. Trained by the pioneer of arthroscopy, Masuki Watanabe, they were setting the basis of a new diagnostic and operative method which was based on the optics and electronics technology. The technical improvment introduced by the digitalization of video capture, transmission and storage, has made possible the establishment of artroscopic surgery as a precise, minimal invasive procedure. A new range of possibilities in treating ligament meniscal and cartilage injuries therefore occured, allowing for restaurative approaches and improved postinterventional functional recovery. Torn cruciate ligaments in the knee or recurrent shouder dislocation are no longer a career end for sport professional due to the widespread of reconstructive

Sclerostin regulation of WISP1 and MMPS in chondrocytes is dependent on the LRP5/6 binding domain but not secretion from the cell

Sclerostin regulation of WISP1 and MMPS in chondrocytes is dependent on the LRP5/6 binding domain but not secretion from the cell

Knee osteoarthritis in women

Osteoarthritis is a disease that progresses over time and culminates in the destruction of articular cartilage and joints. Thus, with an increasing elderly population the treatment of knee osteoarthritis has become a major healthcare issue. It has been shown that women are more severely impacted by knee osteoarthritis. Differences in knee anatomy, kinematics, previous knee injury, and hormonal influences may play a role. Sex difference with respect to osteoarthritis presentation, treatment, and the allocation of resources also exists. In general, women present for treatment in more advanced stages of osteoarthritis and have more debilitating pain than their male counterparts. In addition, healthcare providers are more likely to recommend total joint arthroplasty for their male patients. Understanding how and why these gender differences occur is instrumental in formulating an inclusive strategy for combating osteoarthritis in the future.

Less Invasive Rotational Acetabular Osteotomy for Hip Dysplasia

BackgroundBroad dissection with a long skin incision and detachment of the gluteus medius muscle performed for rotational acetabular osteotomy (RAO) can result in weakness in abduction strength of the hip. We use a surgical procedure for RAO that minimizes operative invasion of soft tissue and reduces incision length compared with conventional procedures.Questions/PurposesWe evaluated the clinical results of this less-invasive RAO comparing it with the more-invasive prior procedure with respect to improvement in clinical hip scores and radiographic coverage and overall hip survival after the procedure.MethodsIn this less-invasive exposure, the medial gluteus muscle is retracted to expose the ilium without detachment from the iliac crest. Similarly, the rectus femoris muscle tendon is retracted, not excised. The lateral part of the osteotomized ilium is cut to form the bone graft instead of harvesting it from the outer cortical bone of the ilium. Between 2000 and 2009, 62 patients (71 hips) underwent this procedure. Twenty-eight hips had early-stage osteoarthritis and 43 had advanced-stage osteoarthritis. Mean patient age was 40 years at the time of surgery. We evaluated improvement in hip scores (Merle d’Aubigné-Postel, Japanese Orthopaedic Association) and radiographic appearance (lateral center-edge angle, Sharp’s angle, acetabular head index [AHI]). Kaplan-Meier survivorship analysis was performed. Mean followup was 5 years (range, 2.0–10.4 years).ResultsClinical hip scores improved postoperatively. On average, lateral center-edge angle, Sharp’s angle, and AHI improved by 38°, 11°, and 42%, respectively. Predicted 10-year survival rates were 100% and 72% for hips with early- and advanced-stage osteoarthritis, respectively.ConclusionsIn hips with early-stage osteoarthritis treated by this less-invasive approach, no progression of osteoarthritis was documented and Trendelenburg gait was avoided. However, further investigation is necessary for hips with advanced-stage osteoarthritis.Level of EvidenceLevel IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The Chiari pelvic osteotomy for patients with dysplastic hips and poor joint congruency

We report the mid- to long-term (mean 20.3 years, 10 to 32.5) results of the Chiari pelvic osteotomy in patients with pre- to advanced stage osteoarthritis in dysplastic hips. We followed 163 Japanese patients (173 hips) with a mean age at surgery of 20 years (9 to 54). Overall, 124 hips (72%) had satisfactory results, with Harris hip scores ≥ 80. Satisfactory results were seen in 105 of 134 hips with pre- or early osteoarthritis (78%) and 19 of 39 hips with advanced osteoarthritis (49%). A total of 15 hips (9%) underwent a total hip replacement (THR) with a mean interval between osteotomy and THR of 16.4 years. With conversion to THR as the endpoint, the 30-year survival rate was 85.9% (95% confidence interval 82.3 to 89.5). It was 91.8% for patients with pre- or early osteoarthritis and 43.6% for those with advanced osteoarthritis (p < 0.001). We now perform the Chiari osteotomy for patients with dysplastic hips showing poor joint congruency and who prefer a joint-conserving procedure to THR.

Application of in vivo micro-computed tomography in the temporal characterisation of subchondral bone architecture in a rat model of low-dose monosodium iodoacetate-induced osteoarthritis

IntroductionOsteoarthritis (OA) is a complex, multifactorial joint disease affecting both the cartilage and the subchondral bone. Animal models of OA aid in the understanding of the pathogenesis of OA and testing suitable drugs for OA treatment. In this study we characterized the temporal changes in the tibial subchondral bone architecture in a rat model of low-dose monosodium iodoacetate (MIA)-induced OA using in vivo micro-computed tomography (CT).MethodsMale Wistar rats received a single intra-articular injection of low-dose MIA (0.2 mg) in the right knee joint and sterile saline in the left knee joint. The animals were scanned in vivo by micro-CT at two, six, and ten weeks post-injection, analogous to early, intermediate, and advanced stages of OA, to assess architectural changes in the tibial subchondral bone. The articular cartilage changes in the tibiae were assessed macroscopically and histologically at ten weeks post-injection.ResultsInterestingly, tibiae of the MIA-injected knees showed significant bone loss at two weeks, followed by increased trabecular thickness and separation at six and ten weeks. The trabecular number was decreased at all time points compared to control tibiae. The tibial subchondral plate thickness of the MIA-injected knee was increased at two and six weeks and the plate porosity was increased at all time points compared to control. At ten weeks, histology revealed loss of proteoglycans, chondrocyte necrosis, chondrocyte clusters, cartilage fibrillation, and delamination in the MIA-injected tibiae, whereas the control tibiae showed no changes. Micro-CT images and histology showed the presence of subchondral bone sclerosis, cysts, and osteophytes.ConclusionsThese findings demonstrate that the low-dose MIA rat model closely mimics the pathological features of progressive human OA. The low-dose MIA rat model is therefore suitable to study the effect of therapeutic drugs on cartilage and bone in a non-trauma model of OA. In vivo micro-CT is a non-destructive imaging technique that can track structural changes in the tibial subchondral bone in this animal model, and could also be used to track changes in bone in preclinical drug intervention studies for OA treatments.

Increased friction coefficient and superficial zone protein expression in patients with advanced osteoarthritis

To quantify the concentration of superficial zone protein (SZP) in the articular cartilage and synovial fluid of patients with advanced osteoarthritis (OA) and to further correlate the SZP content with the friction coefficient, OA severity, and levels of proinflammatory cytokines. Samples of articular cartilage and synovial fluid were obtained from patients undergoing elective total knee replacement surgery. Additional normal samples were obtained from donated body program and tissue bank sources. Regional SZP expression in cartilage obtained from the femoral condyles was quantified by enzyme-linked immunosorbent assay (ELISA) and visualized by immunohistochemistry. Friction coefficient measurements of cartilage plugs slid in the boundary lubrication system were obtained. OA severity was graded using histochemical analyses. The concentrations of SZP and proinflammatory cytokines in synovial fluid were determined by ELISA. A pattern of SZP localization in knee cartilage was identified, with load-bearing regions exhibiting high SZP expression. SZP expression patterns were correlated with friction coefficient and OA severity; however, SZP expression was observed in all samples at the articular surface, regardless of OA severity. SZP expression and aspirate volume of synovial fluid were higher in OA patients than in normal controls. Expression of cytokines was elevated in the synovial fluid of some patients. Our findings indicate a mechanochemical coupling in which physical forces regulate OA severity and joint lubrication. The findings of this study also suggest that SZP may be ineffective in reducing joint friction in the boundary lubrication mode at an advanced stage of OA, where other mechanisms may dominate the observed tribological behavior.

Complement activation and regulation in early and advanced stage osteoarthritis

Although not considered a classical inflammatory arthropathy, osteoarthritis (OA) is often associated with lowgrade synovitis. The stimuli required to establish inflammation in OA synovium are as yet unclear, but there...

A longitudinal analysis of urinary biochemical markers and bone mineral density in STR/Ort mice as a model of spontaneous osteoarthritis

To investigate the longitudinal changes both in the urinary concentrations of biochemical markers and in bone mineral density (BMD) during disease progression in the STR/Ort mouse model of osteoarthritis (OA). Male STR/Ort mice were studied, with CBA mice used as nonarthritic controls. Radiographic evaluation and grading of the knee and measurements of urinary C-terminal crosslinking telopeptide of type II collagen (CTX-II), pyridinoline (Pyr), and deoxypyridinoline were performed between 8 weeks and 40 weeks of age. The BMD of the femoral shaft was measured from 20 weeks to 40 weeks of age and adjusted for body weight. Histologic evaluation and grading were performed at 40 weeks of age. STR/Ort mice were divided into 2 subgroups (STR OA and STR non-OA) based on histologic grading. No significant differences between STR/Ort and CBA mice were observed for any biochemical marker or BMD at any time point. Urinary CTX-II levels and BMD in the STR OA subgroup were higher than those in the STR non-OA subgroup before radiographic changes of OA were apparent. Higher urinary Pyr levels in the STR OA subgroup were observed at the advanced stage of OA. Urinary CTX-II could be a useful marker in the early diagnosis and predicting the progression of OA, and urinary Pyr may be a potential marker to assess the severity of OA at an advanced stage. An increase in BMD prior to the establishment of radiographic OA may be related to the induction of OA.

Hyaluronic acid modulates gene expression of connective tissue growth factor (CTGF), transforming growth factor-β1 (TGF-β1), and vascular endothelial growth factor (VEGF) in human fibroblast-like synovial cells from advanced-stage osteoarthritis in vitro

Intraarticular injection of hyaluronan (hyaluronic acid; HA) is the common way to treat osteoarthritis (OA) of knees. This treatment cannot only maintain the viscoelastic properties of knee but also release the OA pain. However, the exact molecular mechanism is unknown. In this study, after human synovial cells were stimulated with HA and Hylan (Synvisc) for 24 h, real-time polymerase chain reaction (real-time PCR) was used to detect the alteration of connective tissue growth factor (CTGF), transforming growth factor-beta1 (TGF-beta1), and vascular endothelial growth factor (VEGF) gene expression, which were specific genes related to pathogenesis of OA knees. Our results illustrated that both HA and Hylan might not cause cytotoxicity or apoptosis of synovial cells in serum deprivation environment. The gene expressions of TGF-beta1 and VEGF were significantly increased at the concentration of 0.1 mg/mL HA and 0.1 mg/mL Hylan, respectively (alpha < 0.05). The synovial cells with treatment of 0.1 mg/mL Hylan decreased the CTGF gene expression (0.66-fold) and VEGF (0.78-fold) compared to 0.1 mg/mL HA (alpha < 0.05). We suggested that the profile of CTGF, TGF-beta1, and VEGF gene expressions in our study might provide the rational mechanism for the therapeutic effect of hyaluronan on OA knees.

A COL2A1 gene polymorphism is related with advanced stages of osteoarthritis of the knee in Mexican Mestizo population

Primary osteoarthritis (OA) is a multifactorial disease with several genetics factors involved. The COL2A1 gene is of particular interest because it encodes for the most abundant protein in articular cartilage. The aim was to evaluate the association of COL2A1 gene polymorphism with OA of the knee in Mexican Mestizo patients. A case-control study was conducted; cases comprised patients with a radiologic scoring > or = 2 and controls with a radiologic scoring <2. DNA was extracted from a peripheral blood sample, the polymorphic site of the COL2A1 gene was submitted to polymerase chain reaction (PCR), and the products were digested using PvuII restriction enzyme. For statistical analysis, a non-conditional logistic regression was developed. There were no associations among alleles in the overall sample, nevertheless, a significant association was found with p (Pp/pp) allele and OA of the knee grade 4 [odds ratio (OR), 95% confidence interval (CI 95%) 4.1 (1.2-14.6)] adjusted by gender, age, and body mass index (BMI). These results suggest an association of a COL2A1 gene polymorphism with advanced stages of OA of the knee in Mexican Mestizo population.

Depth-wise progression of osteoarthritis in human articular cartilage: investigation of composition, structure and biomechanics

Osteoarthritis (OA) is characterized by the changes in structure and composition of articular cartilage. However, it is not fully known, what is the depth-wise change in two major components of the cartilage solid matrix, i.e., collagen and proteoglycans (PGs), during OA progression. Further, it is unknown how the depth-wise changes affect local tissue strains during compression. Our aim was to address these issues. Data from the previous microscopic and biochemical measurements of the collagen content, distribution and orientation, PG content and distribution, water content and histological grade of normal and degenerated human patellar articular cartilage (n=73) were reanalyzed in a depth-wise manner. Using this information, a composition-based finite element (FE) model was used to estimate tissue function solely based on its composition and structure. The orientation angle of collagen fibrils in the superficial zone of cartilage was significantly less parallel to the surface (P<0.05) in samples with early degeneration than in healthy samples. Similarly, PG content was reduced in the superficial zone in early OA (P<0.05). However, collagen content decreased significantly only at the advanced stage of OA (P<0.05). The composition-based FE model showed that under a constant stress, local tissue strains increased as OA progressed. For the first time, depth-wise point-by-point statistical comparisons of structure and composition of human articular cartilage were conducted. The present results indicated that early OA is primarily characterized by the changes in collagen orientation and PG content in the superficial zone, while collagen content does not change until OA has progressed to its late stage. Our simulation results suggest that impact loads in OA joint could create a risk for tissue failure and cell death.

La artrosis como enfermedad genética

La artrosis es un ejemplo de enfermedad compleja, que se origina por la interacción de factores genéticos y ambientales. En este trabajo revisamos los diferentes tipos de estudios que permiten analizar la contribución de los factores genéticos a la patogenia de las enfermedades complejas y los genes cuyos polimorfismos se han relacionado con el riesgo de desarrollar artrosis. Dado el importante beneficio que aporta la cirugía a los pacientes con artrosis avanzada, cabría plantearse si estos estudios genéticos tienen realmente alguna utilidad. La respuesta es claramente afirmativa. Por un lado, el conocimiento de los factores genéticos implicados en la aparición y el desarrollo de la artrosis puede permitir identificar y controlar subgrupos de individuos de mayor riesgo en fases precoces. Por otro lado, la identificación de los genes involucrados puede llevar a determinar nuevas dianas terapéuticas que permitan frenar de manera eficaz el desarrollo del proceso, algo que no podemos ofrecer a nuestros pacientes en la actualidad. Osteoarthritis is an example of a complex disease, which arises from the interaction of genetic and environmental factors. In this paper we review the different types of studies that can be conducted in order to analyze the contribution of genetic factors to the pathogenesis of complex diseases as well as the genes whose polymorphisms have been associated to the risk of developing osteoarthritis. The significant benefits that surgery can offer patients with advanced-stage osteoarthritis beg the question of whether there genetic studies are really of any use. The answer is clearly in the affirmative. On the one hand, an awareness of the genetic factors involved in the onset and development of osteoarthritis may help identify and control subgroups of individuals who are at a higher risk at an early stage. Furthermore, identification of the genes involves could help discover new therapeutic targets that may lead to effectively halting the process, which is something we cannot do with our patients at present.

Transposition osteotomy of the acetabulum for advanced-stage osteoarthritis of the hips

BackgroundTransposition osteotomy of the acetabulum (TOA) was the first periacetabular osteotomy in which the acetabulum was transposed with articular cartilage. TOA improves coverage of the femoral head and joint congruity. The purpose of this study was to investigate whether TOA is an appropriate option for treating osteoarthritis of the hips at the advanced stage by comparing it with matched control hips at the early stage. MethodsBetween 1998 and 2001, TOA was performed in 104 hips of 98 patients. Altogether, 16 of 17 hips (94%) with osteoarthritis at the advanced stage were examined and compared with 37 matched control hips at the early stage. The mean age at the operation was 48 years (38-56 years), and the mean follow-up period was 88 months (65-107 months). ResultsTOA corrected the acetabular dysplasia and significantly improved containment of the femoral head. Clinical scores were also significantly improved in both groups. In the advanced osteoarthritis cases, there was a tendency for abduction congruity before transposition osteotomy of the acetabulum to reflect the clinical outcome. ConclusionsTOA is a promising treatment option for advanced osteoarthritis of the hips as well as for patients at an early stage when preoperative radiographs show good con-gruity or containment of the joint.

Joint Congruency as an Indication for Rotational Acetabular Osteotomy

Long-term results of periacetabular osteotomy for advanced-stage osteoarthritis secondary to developmental dysplasia of the hip are reportedly unsatisfactory compared with results for early-stage osteoarthritis. Other preoperative information that can be used to determine indications for periacetabular osteotomy is therefore important to avoid performing osteotomy in young patients with advanced-stage osteoarthritis who would not likely achieve substantial benefit. We retrospectively reviewed 47 patients (49 hips) with advanced-stage osteoarthritis who underwent rotational acetabular osteotomy (RAO) using preoperative congruency in abduction. The minimum postoperative followup was 8 years (mean, 12.3 years; range, 8-20 years) and mean age at surgery was 43.1 years (range, 30-59 years). At followup, osteoarthritic stage was improved in 12 hips, unchanged in 24 hips, and had progressed in 13 hips. Preoperative joint congruency in abduction was good in 13 hips, poor in 32 hips, and narrowed in four hips. Patients with better congruency in abduction had better results. We believe osteoarthritis with good congruency in abduction preoperatively remains a good indication for RAO even in advanced stages of disease. Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Rotational acetabular osteotomy with excision of the capital drop for advanced osteoarthritis secondary to developmental dysplasia of the hip

Advanced-stage osteoarthritis may occasionally be associated with capital drop of the femoral head. In such cases, excision of the capital drop is performed to obtain good congruency with sufficient coverage of the femoral head by rotational acetabular osteotomy (RAO). In the present study, we examined the outcome of RAO with excision of the capital drop. Rotational acetabular osteotomy (RAO) with excision of the capital drop was performed in 17 hips of 16 patients with a mean follow-up of 12.6 years (excision group), while only RAO was performed in 42 hips of 41 patients with a mean follow-up of 12.3 years (non-excision group). All 57 patients indicated radiographic evidence of advanced-stage osteoarthritis. Clinical follow-up was performed using the Merle d'Aubigné and Postel system. The clinical and radiological results were compared between the two groups. The mean Merle d'Aubigne and Postel's total hip-joint scores at follow up significantly (p < 0.001) improved compared with the mean pre-operative scores only in the non-excision group. While the numbers of hips in excision group (17 hips) showing progressive and non-progressive osteoarthritic changes were 10 and 7, those in the non-excision group (42 hips) were 11 and 20, respectively. Although none (0/17) in the excision group showed any improvement in osteoarthritic stage at follow up, 11 of 42 hips indicated a favorable outcome in the non-excision group. There were significantly (p = 0.0077) higher improvements in osteoarthritis stage in the non-excision than excision group. Three patients each of the excision group (18%) and non-excision group (7%) underwent total hip arthroplasty during the follow-up period. Excision of capital drop of the femoral head is not a useful adjunct to the RAO procedure for the treatment of advanced osteoarthritis. Based on results from a previous study, Chiari pelvic osteotomy may serve as a more favorable alternative.

Rotational Acetabular Osteotomy for Advanced Osteoarthritis Secondary to Dysplasia of the Hip

Satisfactory intermediate and long-term results of rotational acetabular osteotomy for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study was to examine the results of rotational acetabular osteotomy in patients with advanced osteoarthritis secondary to developmental dysplasia of the hip. We performed a retrospective review of the results of rotational acetabular osteotomy in forty-three patients (forty-three hips). All of the patients had radiographic evidence of advanced-stage osteoarthritis, defined as narrowing of the joint space with cystic radiolucencies and small osteophytes according to the staging system of the Japanese Orthopaedic Association. Forty-one patients were female, and two were male. The mean age was 43.8 years at the time of surgery, and the mean duration of follow-up was 8.5 years. Clinical follow-up was performed with use of the system of Merle d'Aubigné and Postel. The center-edge angle, acetabular roof angle, head lateralization index, and minimum width of the joint space were measured on radiographs made preoperatively, postoperatively, and at the time of final follow-up. Postoperative joint congruency was classified into four grades. The mean preoperative Merle d'Aubigné clinical score was 13.3 points, which improved to a mean of 15.4 points at the time of the latest follow-up (p < 0.0001). The mean center-edge angle improved from 0.7 degrees preoperatively to 29 degrees at three months postoperatively (p < 0.0001), the mean acetabular roof angle improved from 30 degrees to 11 degrees (p < 0.0001), the mean head lateralization index improved from 0.69 to 0.65 (p < 0.01), and the mean minimum width of the joint space improved from 2.2 to 2.5 mm (p < 0.0003). Ten hips had radiographic evidence of progression of osteoarthritis. Kaplan-Meier survivorship analysis, with radiographic signs of progression of osteoarthritis as the end point, predicted a ten-year survival rate of 72.2%. Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip in properly selected patients can improve clinical scores and is associated with a lack of radiographic signs of progression of osteoarthritis in most patients.

ROTATIONAL ACETABULAR OSTEOTOMY FOR ADVANCED OSTEOARTHRITIS SECONDARY TO DYSPLASIA OF THE HIP

Background: Satisfactory intermediate and long-term results of rotational acetabular osteotomy for the treatment of early osteoarthritis secondary to developmental dysplasia of the hip have been reported. The purpose of this study was to examine the results of rotational acetabular osteotomy in patients with advanced osteoarthritis secondary to developmental dysplasia of the hip. Methods: We performed a retrospective review of the results of rotational acetabular osteotomy in forty-three patients (forty-three hips). All of the patients had radiographic evidence of advanced-stage osteoarthritis, defined as narrowing of the joint space with cystic radiolucencies and small osteophytes according to the staging system of the Japanese Orthopaedic Association. Forty-one patients were female, and two were male. The mean age was 43.8 years at the time of surgery, and the mean duration of follow-up was 8.5 years. Clinical follow-up was performed with use of the system of Merle d'Aubigné and Postel. The center-edge angle, acetabular roof angle, head lateralization index, and minimum width of the joint space were measured on radiographs made preoperatively, postoperatively, and at the time of final follow-up. Postoperative joint congruency was classified into four grades. Results: The mean preoperative Merle d'Aubigné clinical score was 13.3 points, which improved to a mean of 15.4 points at the time of the latest follow-up (p < 0.0001). The mean center-edge angle improved from 0.7° preoperatively to 29° at three months postoperatively (p < 0.0001), the mean acetabular roof angle improved from 30° to 11° (p < 0.0001), the mean head lateralization index improved from 0.69 to 0.65 (p < 0.01), and the mean minimum width of the joint space improved from 2.2 to 2.5 mm (p < 0.0003). Ten hips had radiographic evidence of progression of osteoarthritis. Kaplan-Meier survivorship analysis, with radiographic signs of progression of osteoarthritis as the end point, predicted a ten-year survival rate of 72.2%. Conclusions: Rotational acetabular osteotomy for advanced osteoarthritis secondary to dysplasia of the hip in properly selected patients can improve clinical scores and is associated with a lack of radiographic signs of progression of osteoarthritis in most patients. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.