A novel cell source for therapy of knee osteoarthritis using atelocollagen microsphere-adhered adipose-derived stem cells: Impact of synovial fluid exposure on cell activity.

Introduction: Administration of adipose-derived stem cells (ADSCs) into the joint cavity has been shown to alleviate the symptoms of knee osteoarthritis (OA) by releasing exosomes and anti-inflammatory cytokines. However, the therapeutic effect of these cells is limited by their rapid disappearance after administration. Thus, it is necessary to prolong cell survival in the joint cavity. This study aimed to investigate the potential application of ADSCs adhered to atelocollagen microspheres (AMSs) for cell therapy of knee OA. Methods: ADSCs were cultured for 2, 4, and 7 days in AMS suspension or adherent culture dishes. The supernatants were analyzed for IL-10 and exosome secretion via enzyme-linked immunosorbent assay and Nanosight. The effect of AMS was compared with that of adherent-cultured ADSCs (2D-cultured ADSCs) using transcriptome analysis. Moreover, the solubility of AMS and viability of ADSCs were evaluated using synovial fluid (SF) from patients with knee OA. Results: Compared with 2D-cultured ADSCs, AMS-cultured ADSCs exhibited a significant increase in secretion of exosomes and IL-10, and the expression of several genes involved in extracellular matrix and immune regulation were altered. Furthermore, when AMS-cultured ADSCs were cultured in SF from knee OA patients to mimic the intra-articular environment, the SF dissolved the AMSs and released viable ADSCs. In addition, AMS-cultured ADSCs showed significantly higher long-term cell viability than 2D-cultured ADSCs. Conclusion: Increased survival of AMS-adhered ADSCs was observed in the intra-articular environment, and AMSs were found to gradually dissipate. These results suggest that AMS-adhered ADSCs are promising source for cell therapy of knee OA.

Life Course Epidemiology of Hip Osteoarthritis in Japan: A Multicenter, Cross-Sectional Study.

BACKGROUND: The incidence of developmental dysplasia of the hip (DDH) in Japanese newborns has reduced drastically following a primary prevention campaign initiated around 1972 to 1973; this perinatal education campaign promoted maintaining the hips of newborns in the naturally flexed-leg position. The purpose of the present study was to describe the life course epidemiology of hip osteoarthritis (OA) in adolescent and adult patients and to assess its association with exposure to the primary prevention campaign for DDH. METHODS: We included new patients with hip OA diagnosed from January 1, 2022, to December 31, 2022, at 12 core hospitals (8 special-function hospitals and 4 regional medical care support hospitals). The trend in the percentage of hips with a history of DDH treatment in childhood was estimated with use of a centered moving average using the birth year of the patient. We compared the prevalence of severe subluxation (Crowe type II, III, or IV) between patients with secondary hip OA due to hip dysplasia who were born in or before 1972 and those who were born in or after 1973. RESULTS: Overall, 1,095 patients (1,381 hips) were included. The mean age at the time of the survey was 63.5 years (range, 15 to 95 years). A total of 795 patients (1,019 hips; 73.8% of hips) were diagnosed with secondary OA due to hip dysplasia. Approximately 13% to 15% of hips among patients born from 1963 to 1972 had a history of DDH treatment in childhood; however, the percentage decreased among patients born in or after 1973. The prevalence of severe subluxation (Crowe type II, III, or IV) among patients born in or after 1973 was 2.4%, which was significantly less than that among patients born in or before 1972 (11.1%; odds ratio, 0.20; p < 0.001). CONCLUSIONS: As of 2022, secondary hip OA due to hip dysplasia is still responsible for most new cases of adolescent and adult hip OA seen in core hospitals in Japan. However, the perinatal education campaign initiated 50 years ago, which utilized a population approach and advocated for maintaining the hips of newborns in the naturally flexed-leg position, may have improved the environmental factors of DDH, as indicated by the apparently reduced need for treatment of DDH in childhood and the associated severe subluxation. This may result in a reduced need for challenging hip surgery later in life. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Time elapsed from definitive diagnosis to surgery for osteonecrosis of the femoral head: a nationwide observational study in Japan.

OBJECTIVES: This study documents the time elapsed from the diagnosis of osteonecrosis of the femoral head (ONFH) to surgery, exploring the factors that influence ONFH severity. DESIGN: Retrospective observational study of a nationwide database. SETTING: The Kaplan-Meier method with log-rank tests was applied to examine the period from definitive diagnosis of ONFH to surgery using any surgery as the end point. For bilateral cases, the date of the first surgery was the endpoint. PARTICIPANTS: This study included 2074 ONFH cases registered in 34 university hospitals and highly specialised hospitals of the multicentre sentinel monitoring system of the Japanese Investigation Committee between 1997 and 2018. MAIN OUTCOME MEASURE: The primary outcome was the time from diagnosis to surgery. The secondary outcome was the proportion of subjects remaining without surgery at 3, 6 and 9 months, and at 1, 2 and 5 years after diagnosis. RESULTS: The median time to surgery was 9 months (IQR 4-22 months) after diagnosis of ONFH. The time to surgery was significantly shorter in the alcohol alone group and the combined corticosteroid and alcohol group than in the corticosteroid alone group (p=0.018 and p<0.001, respectively), in early stage ONFH with no or mild joint destruction (stages II and III, p<0.001), and with joint preserving surgery (p<0.001). The proportion without surgery was 75.8% at 3 months, 59.6% at 6 months, 48.2% at 9 months, 40.5% at 1 year, 22.2% at 2 years and 8.3% at 5 years. CONCLUSION: ONFH has been considered to be an intractable disease that often requires surgical treatment, but the fact that surgery was performed in more than half of the patients within 9 months from diagnosis suggests severe disease with a significant clinical impact. TRIAL REGISTRATION NUMBER: Chiba University ID1049.

Hip-sacroiliac joint-spine syndrome in total hip arthroplasty patients.

This study is designed to compare the extent of sacroiliac joint (SIJ) degeneration at total hip arthroplasty (THA) for two pathologies: osteoarthritis of the hip (OA) and osteonecrosis of the femoral head (ON). We also assessed the prevalence of SIJ degeneration in patients with lumbar spondylolisthesis or degenerative scoliosis. A total of 138 hips from 138 patients (69 OA and 69 ON) were assessed in this study, including 66 hips affected by OA secondary to developmental dysplasia of the hip. The degenerative changes in the SIJ and lumbar spine were evaluated prior to THA using radiographs and computed tomography (CT) scans, showing 9 instances of spondylolisthesis and 38 of degenerative scoliosis. The OA group exhibited longer duration from onset to surgery than the ON group. The OA group also included more cases with significant pelvic obliquity (3 degrees or more) and with significant increases in SIJ sclerosis and irregularities. Patients with lumbar spondylolisthesis or degenerative scoliosis were significantly more likely to have SIJ irregularities. The prevalence of SIJ degeneration was higher in cases of THA for OA than for ON. This study also suggests the possibility of Hip-SIJ-Spine syndrome in THA patients with OA.

Septic Arthritis of Cervical Spine Facet Joints: A Case Report and Review of Imaging.

BACKGROUND Septic arthritis of the facet joint (SAFJ) has been considered a rare type of spinal infection. However, because of the aging of the population, the increase in compromised hosts, and the increase in MRI use in recent years, the number of reports has been increasing. We report the clinical progress of a rare case of septic arthritis of the cervical facet joint (SACFJ) with some imaging considerations, and we compare our findings with existing reports of SACFJ. CASE REPORT A 73-year-old Japanese woman presented with fever, paralytic symptoms, and paresthesia of the upper limbs. Here, we report a case of SACFJ in which MRI findings allowed early diagnosis, and a favorable course was obtained by conservative treatment with antibiotics. Although MRI performed 93 days after the initiation of treatment showed a slight residual signal change in the facet joints, no symptoms had recurred by the sixth month after hospital discharge. CONCLUSIONS If a patient develops neurological symptoms such as paralysis with fever and increased inflammatory response, the physician must consider the possibility of pyogenic spondylitis, including SACFJ, and order an MRI. Epidural abscess is almost inevitable in SACFJ, and surgical treatment, including abscess drainage, is required if spinal cord or paralytic symptoms progress. For patients with SACFJ, as well as pyogenic spondylitis, MRI may not be useful in determining treatment efficacy.

A Case of Axillary Web Syndrome Caused by Venous Blood Sampling.

Axillary web syndrome (AWS) occurs after breast cancer surgery, sentinel lymph node dissection, or sentinel lymph node biopsy. Here, cord-like structures from the axilla to the forearm limit the range of motion of the shoulder joint and cause pain. Although the etiology is unknown, AWS has been attributed to the blockage of normal lymphatic flow. Here, we report a novel case of AWS after venous blood sampling in a patient. A healthy, 31-year-old male patient experienced pain with a limited range of motion of the shoulder joint the day after venous blood was collected from the left upper extremity for a medical checkup, and he presented to an orthopedic outpatient clinic on the day. Palpation of the axillary region disclosed a cord-like structure in the axillary region of the shoulder joint during abduction, and the patient was diagnosed with AWS. The cord-like structure was noted to be a hypoechogenic luminal structure on ultrasound (US) examination of the axilla, extending from the axilla to below the ulnar cutaneous vein from which the blood was drawn. In patients with pain and a limited range of motion of the shoulder joint, only the shoulder joint is examined during an orthopedic examination. It is important to obtain appropriate physical findings for possible AWS.

Comparative Study of Highly Cross-Linked Polyethylene Liner Wear by Hip Center Location Using Elevated Hip Center Technique in Crowe I to III Hip Dysplasia: Outcomes for a Minimum of Eighteen Years of Follow-Up.

BACKGROUND: The literature has reported that supero-lateralization of the femoral head increases the rates of aseptic loosening and prosthesis revision. However, there are few reports on the influence of different hip center positions on liner wear with more than a 15-year follow-up period. METHODS: From April 2000 to August 2003, 91 patients underwent 108 total hip arthroplasties using a highly cross-linked polyethylene liner combined with zirconia femoral head and cup components. Pelvic radiographs were used to assess the vertical and horizontal distances to the center of the hip and the amount of liner wear. Mean patient age at the time of surgery was 54 years (range, 33 to 73), and mean follow-up duration was 19 years (range, 18 to 21). RESULTS: Average liner wear was 0.221 mm, with average annual wear of 0.012 mm/year. Mean vertical and horizontal distances for the hip center were 24.9 and 31.8 mm, respectively. There was no difference in linear wear between patients who had different hip center heights (<20, 20 to 30, and >30 mm), and quadrant partitioning showed no differences across the 4 quadrant zones. CONCLUSION: At a minimum of 18 years of follow-up in patients having developmental dysplasia of the hip who had different Crowe subtypes and different hip centers, elevated hip center and uncemented fixation techniques using a highly cross-linked polyethylene on ceramic components were associated with very low wear rates and excellent functional scores.

Collarless Polished Tapered Stems of Identical Shape Provide Differing Outcomes for Stainless Steel and Cobalt Chrome: A Biomechanical Study.

Cemented polished tapered femoral stems (PTS) made of cobalt-chrome alloy (CoCr) are a known risk factor for periprosthetic fracture (PPF). The mechanical differences between CoCr-PTS and stainless-steel (SUS) PTS were investigated. CoCr stems having the same shape and surface roughness as the SUS Exeter® stem were manufactured and dynamic loading tests were performed on three each. Stem subsidence and the compressive force at the bone-cement interface were recorded. Tantalum balls were injected into the cement, and their movement was tracked to indicate cement movement. Stem motions in the cement were greater for the CoCr stems than for the SUS stems. In addition, although we found a significant positive correlation between stem subsidence and compressive force in all stems, CoCr stems generated a compressive force over three times higher than SUS stems at the bone-cement interface with the same stem subsidence (p < 0.01). The final stem subsidence amount and final force were greater in the CoCr group (p < 0.01), and the ratio of tantalum ball vertical distance to stem subsidence was significantly smaller for CoCr than for SUS (p < 0.01). CoCr stems appear to move more easily in cement than SUS stems, which might contribute to the increased occurrence of PPF with the use of CoCr-PTS.

Synovial Fluid Derived from Human Knee Osteoarthritis Increases the Viability of Human Adipose-Derived Stem Cells through Upregulation of FOSL1.

Knee osteoarthritis (Knee OA) is an irreversible condition that causes bone deformity and degeneration of the articular cartilage that comprises the joints, resulting in chronic pain and movement disorders. The administration of cultured adipose-derived stem cells (ADSCs) into the knee joint cavity improves the clinical symptoms of Knee OA; however, the effect of synovial fluid (SF) filling the joint cavity on the injected ADSCs remains unclear. In this study, we investigated the effect of adding SF from Knee OA patients to cultured ADSCs prepared for therapeutic use in an environment that mimics the joint cavity. An increase in the viability of ADSCs was observed following the addition of SF. Gene expression profiling of SF-treated ADSCs using DNA microarrays revealed changes in several genes involved in cell survival. Of these genes, we focused on FOSL1, which is involved in the therapeutic effect of ADSCs and the survival and proliferation of cancer stem cells. We confirmed the upregulation of FOSL1 mRNA and protein expression using RT-PCR and western blot analysis, respectively. Next, we knocked down FOSL1 in ADSCs using siRNA and observed a decrease in cell viability, indicating the involvement of FOSL1 in the survival of ADSCs. Interestingly, in the knockdown cells, ADSC viability was also decreased by SF exposure. These results suggest that SF enhances cell viability by upregulating FOSL1 expression in ADSCs. For therapy using cultured ADSCs, the therapeutic effect of ADSCs may be further enhanced if an environment more conducive to the upregulation of FOSL1 expression in ADSCs can be established.

Angular changes in pelvic tilt and cup orientation at a minimum of eighteen years after primary total hip arthroplasty with an uncemented cup.

BACKGROUND: Changes in pelvic tilt angle (PTA) and cup orientation have been reported in patients after total hip arthroplasty, but the current literature generally has a brief follow-up period. This study will be the first to report PTA and cup orientation changes in the supine position for a minimum 18 years after total hip arthroplasty (THA) and investigate the factors associated with pelvic tilt and cup orientation changes. METHODS: In this study, 101 patients (120 hips) who underwent THA were retrospectively analyzed. The aims of our study were to evaluate the PTA and cup orientation change over 18 years after THA to assess differential PTA, cup inclination, and anteversion. We also investigated whether factors such as gender, body mass index, and age have any influence on PTA and cup orientation after THA. RESULTS: Patients showed a significant incremental change in PTA pre-operatively, immediately post-operatively, and at final follow-up. Cup orientation increased significantly at the final follow-up compared to the immediate post-operative period. Gender subgroup analysis showed that PTA was significantly greater in females than in males at the final follow-up (p = 0.025). Age subgroup analysis showed that PTA was significantly greater in the over 60 years group than in the other groups. CONCLUSION: Our patients showed significant changes in PTA and cup orientation at a minimum 18 years after surgery, especially in females over 60 years. Female patients over 60 are a risk factor after THA.

Does the Dual Mobility Cup Reduce Dislocation After Primary Total Hip Arthroplasty in Elderly Patients at High Risk of Dislocation?

OBJECTIVE: The dual mobility cup (DMC) is designed to extend the longevity of the prosthesis by improving stability, enhancing the range of motion, and decreasing impingement without increasing wear. We hypothesized that DMC would reduce the risk of dislocation in elderly patients. This study aimed to investigate the clinical and radiographic outcomes of DMC-total hip arthroplasty (THA) in elderly patients at high risk of dislocation. METHODS: From June 2016 to March 2020, 94 patients with a mean age of 77.7 years (97 hips) who underwent a posterolateral approach for DMC-THA in our department were followed up for at least one year. Preoperative and postoperative pelvic tilt angles (PTA) and DMC orientation were prospectively collected for all patients. Intraoperative and postoperative complications were recorded. A parametric test was used for normal distribution, and a non-parametric test was used for non-normal distribution. RESULTS: Abduction and anteversion angles of the cup were 42.4 and 18.0° in the supine position immediately postoperative. The average PTA for patients in the supine and standing positions were 26.5 and 34.5°, respectively. When moving from the supine to the standing position, patients experienced a mean posterior pelvic tilt of 9°. No intraoperative acetabular-related complications were recorded. Postoperative complications included early infection in one patient (1.0%) and dislocation in one patient (1.0%). CONCLUSION: Our study demonstrates that DMC-THA provides satisfactory short-term outcomes in elderly patients at a high risk of dislocation, regardless of the change in PTA resulting from postural transition.

Current Research on Subchondral Insufficiency Fracture of the Femoral Head.

Subchondral insufficiency fracture (SIF) of the femoral head is one of the predominant etiologies of rapidly progressive osteoarthritis of the hip (RPOH). SIF is a rare disease that causes acute pain in the hip joint. It is most frequently found in elderly women with osteoporosis. It is often underdiagnosed or misdiagnosed as osteonecrosis of the femoral head. SIF is currently a well-established cause of RPOH; however, the deeper etiology of SIF is not clear. Good clinical outcomes have been reported for hip preservation therapy and hip replacement. SIF is not obvious radiologically in the early stage, and a T1-weighted magnetic resonance imaging shows a discontinuous low-intensity band under the articular cartilage convex to the articular surface as its characteristic manifestation. Some patients will lose the opportunity to preserve the hip joint due to symptoms such as progressive joint space narrowing and subchondral collapse within a very short period. Patients with progressive hip space narrowing and subchondral collapse on X-ray should be converted to total hip arthroplasty. Based on the characteristics of the disease, surgeons need to master the clinical and radiological characteristics of SIF and strive for early diagnosis and treatment.

A patient-cohort study of numerical analysis on sacroiliac joint stress distribution in pre- and post-operative hip dysplasia.

In acetabular dysplasia, the cartilaginous roof on the acetabular side does not fully cover the femoral head, which may lead to abnormal stress distribution in both the femoral head and pelvis. These stress changes may have implications to the adjacent sacroiliac joint (SIJ). The SIJ has a minimal range of motion and is closely coupled to the adjacent spine and pelvis. In consequence, the SIJ may react sensitively to changes in stress distribution at the acetabulum, with hypermobility-induced pain. The purpose of this study was to investigate the stress distribution of the SIJ in acetabular dysplasia, and to gain insight into the cause and mechanisms of hypermobility-induced pain at the SIJ. Finite element models of pre- and postoperative pelves of four patients with acetabular dysplasia were created and analyzed in double leg standing positions. The preoperative models were relatively inflare, the sacral nutation movement, SIJ cartilage equivalent stress, and the load on the surrounding ligaments decreased with increased posterior acetabular coverage. Acetabular morphology was shown to affect the SIJ, and improvement of the posterior acetabular coverage may help normalize load transmission of the pelvis and thus improve the stress environment of the SIJ in acetabular dysplasia.

A morphological study of adipose-derived stem cell sheets created with temperature-responsive culture dishes using scanning electron microscopy.

Adipose-derived stem cell (ADSC) sheets have potential to be effective in various therapies. In this study, we first demonstrated that a cell sheet composed of human ADSCs could be created using a new temperature-responsive culture dish from the DIC Corporation. The dish can cause detachment of adherent cells due to temperature changes, but a few morphological analyses have evaluated the presence or absence of damage on the detached surface of cell sheet. To characterize our ADSC sheet, we tried to observe the surface of ADSC sheets with scanning electron microscope (SEM) using the ionic liquid, which enables the rapid preparation of samples. No damage was found on the surface of the ADSC sheets on the side that had been in contact with the surface of the culture dishes. In addition, when the transcriptomes of the harvested cell sheets were compared with those of monolayer cultures, no up-regulation of cell death related genes were detected. These results propose that the detachment from temperature-responsive culture dish causes no serious damage on the prepared ADSC sheet. It is also suggested that the SEM with ionic liquids is a useful and rapid method for the analysis of ADSC sheets for therapy.

Evaluation of the Usefulness of Human Adipose-Derived Stem Cell Spheroids Formed Using SphereRing® and the Lethal Damage Sensitivity to Synovial Fluid In Vitro.

Osteoarthritis (OA) is an irreversible degenerative condition causing bone deformation in the joints and articular cartilage degeneration with chronic pain and impaired movement. Adipose-derived stem cell (ADSC) or crushed adipose tissue injection into the joint cavity reportedly improve knee function and symptoms, including pain. Stem cell spheroids may be promising treatment options due to their anti-inflammatory and enhanced tissue regeneration/repair effects. Herein, to form human ADSC spheroids, we used first SphereRing® (Fukoku Co., Ltd., Ageo, Japan), a newly developed rotating donut-shaped tube and determined their characteristics by DNA microarray of mRNA analysis. The variable gene expression cluster was then identified and validated by RT-PCR. Gene expression fluctuations were observed, such as COL15A1 and ANGPTL2, related to vascular endothelial cells and angiogenesis, and TNC, involved in tissue formation. In addition, multiplex cytokine analysis in the medium revealed significant cytokines and growth factors production increase of IL-6, IL-10, etc. However, ADSC administration into the joint cavity involves their contact with the synovial fluid (SF). Therefore, we examined how SF collected from OA patient joint cavities affect 2D-culture ADSCs and ADSC spheroids and observed SF induced cell death. ADSC spheroids could become promising OA treatment options, although studying the administration methods and consider their interaction with SF is essential.

Novel susceptibility loci for steroid-associated osteonecrosis of the femoral head in systemic lupus erythematosus.

Osteonecrosis of the femoral head (ONFH) involves necrosis of bone and bone marrow of the femoral head caused by ischemia with unknown etiology. Previous genetic studies on ONFH failed to produce consistent results, presumably because ONFH has various causes with different genetic backgrounds and the underlying diseases confounded the associations. Steroid-associated ONFH (S-ONFH) accounts for one-half of all ONFH, and systemic lupus erythematosus (SLE) is a representative disease underlying S-ONFH. We performed a genome-wide association study (GWAS) to identify genetic risk factors for S-ONFH in patients with SLE. We conducted a two-staged GWAS on 636 SLE patients with S-ONFH and 95 588 non-SLE controls. Among the novel loci identified, we determined S-ONFH-specific loci by comparing allele frequencies between SLE patients without S-ONFH and non-SLE controls. We also used Korean datasets comprising 148 S-ONFH cases and 37 015 controls to assess overall significance. We evaluated the functional annotations of significant variants by in silico analyses. The Japanese GWAS identified 4 significant loci together with 12 known SLE susceptibility loci. The four significant variants showed comparable effect sizes on S-ONFH compared with SLE controls and non-SLE controls. Three of the four loci, MIR4293/MIR1265 [odds ratio (OR) = 1.99, P-value = 1.1 × 10-9)], TRIM49/NAALAD2 (OR = 1.65, P-value = 4.8 × 10-8) and MYO16 (OR = 3.91, P-value = 4.9 × 10-10), showed significant associations in the meta-analysis with Korean datasets. Bioinformatics analyses identified MIR4293, NAALAD2 and MYO16 as candidate causal genes. MIR4293 regulates a PPARG-related adipogenesis pathway relevant to S-ONFH. We identified three novel susceptibility loci for S-ONFH in SLE.

Spherical Periacetabular Osteotomy.

Various techniques for periacetabular osteotomy have been reported to prevent the progression of osteoarthritis in dysplastic hips1-5. Bernese periacetabular osteotomy, which involves the use of an anterior approach, is widely performed throughout the world because it offers preservation of the blood supply to the bone fragment and lateral pelvic muscles. However, Bernese periacetabular osteotomy has potential complications, such as nonunion at the osteotomy site, postoperative fracture, nonunion of the pubis and ischium, and damage to the main trunk of the obturator artery. Spherical periacetabular osteotomy (SPO) has been developed to resolve some of disadvantages of Bernese periacetabular osteotomy6. Although SPO involves some technical difficulty, the procedure is safe when performed with use of appropriate preoperative 3-dimensional planning and surgical technique. Description: Preoperative 3-dimensional planning is utilized to decide the radius of the curved osteotome, locations of the reference points for the osteotomy line, and depth of the bone groove at the teardrop area. The pelvic positioning is arranged fluoroscopically to match the neutral position based on preoperative planning. A 7-cm incision is made along the medial margin of the iliac crest. An anterior iliac crest osteotomy of 4.5 cm (length) × 1 cm (medial wedge-shaped) is performed. The operative field is maintained with aluminum retractors. The osteotomy line is completed by connecting the preoperatively planned reference points on the inner cortex of the ilium. The bone groove is made along the osteotomy line with use of a high-speed burr. A blunt osteotome is inserted into the bone groove at the teardrop area until it reaches the preoperatively planned depth. The blunt osteotome makes a pathway for the curved osteotome without breaking the quadrilateral surface (QLS) or perforating the hip joint. The special curved osteotome is inserted manually until it reaches the bottom of the groove, and the posterior cortex is cut. After the top of the teardrop is divided fluoroscopically, the anterior ischial cortex is osteotomized with a sharpened spiked Cobb elevator at the infracotyloid groove. An angled curved osteotome is used for the osteotomy of the superior area of the teardrop area. The bone fragment is rotated with a spreader and an angled retractor, and fixed with 2 absorbable screws. Beta-tricalcium phosphate blocks are inserted into the bone gap. The osteotomized wedge-shaped iliac bone is repositioned and fixed. Alternatives: Alternatives include the Bernese periacetabular osteotomy, rotational acetabular osteotomy, and triple innominate osteotomy. Rationale: Bernese periacetabular osteotomy utilizes an anterior approach, cuts into the QLS, and preserves the posterior column. In contrast, SPO preserves the QLS and does not cut the pubis. These features of SPO have some advantages. The large osteotomized surface is advantageous for osseous fusion, and preserving the QLS and pubis protects the trunk of the obturator artery. Furthermore, the preservation of the connection between the ilium, ischium, and pubis in SPO maintains a more stable pelvic ring than in Bernese periacetabular osteotomy. The osteotomy line is arranged to prevent leg shortening caused by thin medial bone stock of the bone fragment. Although splitting the teardrop area in SPO is somewhat technically difficult, particularly in cases with a thin teardrop, it can be safely done with use of preoperative 3-dimensional planning and appropriate surgical technique.In addition, the use of our medial wedge-shaped osteotomy at the iliac crest has 2 advantages: protection of the lateral femoral cutaneous nerve and preservation of the attachment of the tensor fascia latae muscle. Expected Outcomes: The advantages of SPO are a stable pelvic ring postoperatively, reduced risk of nonunion at the osteotomy site, no risk to the trunk of the obturator artery, preservation of the blood supply to the bone fragment, a small incision, and early muscle recovery. Important Tips: Preoperative 3-dimensional planning of the osteotomy design is essential.The special curved osteotomes are designed so that osteotomy of the posterior cortex is completed when the handles are perpendicular to the pelvis.The special curved osteotomes are made with a radius of either 50 or 60 mm, which are the most suitable sizes for the Japanese population. Larger-diameter osteotomes may be required for different races.As the rotated bone fragment is relatively small, it is difficult to obtain rigid fixation of the osteotomy site. Hence, the fragment can move slightly in the early phase after surgery. Careful rehabilitation is needed. Acronyms and Abbreviations: AIIS = anterior inferior iliac spineASIS = anterior superior iliac spineLFCN = lateral femoral cutaneous nerveG.T. = greater trochanterK-wire = Kirschner wireBeta (ß)-TCP = beta-tricalcium phosphate.

The influence of spinopelvic mobility on total hip arthroplasty / 中华骨科杂志

Total hip arthroplasty (THA) has been one of the most successful orthopaedic surgery in the last 50 years, with an excellent survival rate of more than 20 years. However, hip instability, impingement, dislocation, and liner wear remain common causes of THA failure and revision after THA. To minimize the risk of postoperative complications, abnormal spine-pelvic-hip mobility and its impact on THA outcomes have received increasing attention. According to the concept, the patient's pelvic mobility should be fully considered when making preoperative plans for THA. Individualized anteversion and inclination angles should be set according to the patient's sagittal balance and pelvic mobility to reduce the incidence of postoperative adverse events and prolong the life of the prosthesis. In the literature, recent studies have shown that patient aging, postural changes in daily life, high body mass index (BMI), and different surgical approaches and positions can impact spinopelvic mobility. Because changes in pelvic mobility translate into changes in acetabular orientation, excessive intraoperative or postoperative changes in pelvic mobility may result in poor intraoperative prosthesis orientation, postoperative impingement, dislocation, and accelerated liner wear, ultimately shortening the life of the prosthesis. Therefore, it is vital to evaluate and measure spinopelvic mobility preoperatively, investigate the factors that influence intraoperative pelvic mobility changes and the use of assisted positioning devices for accurate cup placement, and observe postoperative changes in pelvic mobility and the resulting adverse outcomes. This review takes the current literature on the spine-pelvic-hip interrelationship as a starting point and presents studies on the factors influencing spinopelvic mobility and the strategies for perioperative management of THA.

Relationship between the Surface Roughness of Material and Bone Cement: An Increased "Polished" Stem May Result in the Excessive Taper-Slip.

Although some reports suggest that taper-slip cemented stems may be associated with a higher periprosthetic femoral fractures rate than composite-beam cemented stems, few studies have focused on the biomaterial effect of the polished material on the stem-cement interface. The purpose of this study was to investigate the relationship between surface roughness of materials and bone cement. Four types of metal discs-cobalt-chromium-molybdenum alloy (CoCr), stainless steel alloy 316 (SUS), and two titanium alloys (Ti-6Al-4V and Ti-15Mo-5Zr-3Al)-were prepared. Five discs of each material were produced with varying degrees of surface roughness. In order to evaluate surface wettability, the contact angle was measured using the sessile drop method. A pin was made using two bone cements and the frictional coefficient was assessed with a pin-on-disc test. The contact angle of each metal increased with decreasing surface roughness and the surface wettability of metal decreased with higher degrees of polishing. With a surface roughness of Ra = 0.06 µm and moderate viscosity bone cement, the frictional coefficient was significantly lower in CoCr than in SUS (p = 0.0073). In CoCr, the low adhesion effect with low frictional coefficient may result in excessive taper-slip, especially with the use of moderate viscosity bone cement.

Recombinant human FGF-2 for the treatment of early-stage osteonecrosis of the femoral head: TRION, a single-arm, multicenter, Phase II trial.

Aim: This study aimed to evaluate the 2-year outcomes from a clinical trial of recombinant human FGF-2 (rhFGF-2) for osteonecrosis of the femoral head (ONFH). Patients & methods: Sixty-four patients with nontraumatic, precollapse and large ONFHs were percutaneously administered with 800 µg rhFGF-2 contained in gelatin hydrogel. Setting the end point of radiological collapse, we analyzed the joint preservation period of the historical control. Changes in two validated clinical scores, bone regeneration and safety were evaluated. Results: Radiological joint preservation time was significantly higher in the rhFGF-2 group than in the control group. The ONFHs tended to improve to smaller ONFHs. The postoperative clinical scores significantly improved. Thirteen serious adverse events showed recovery. Conclusion: rhFGF-2 treatment increases joint preservation time with clinical efficacy, radiological bone regeneration and safety.

Lay abstract Osteonecrosis of the femoral head is a disease that causes pain in the hip joint, making it impossible to walk. The causes of the disease are the use of corticosteroids and the drinking of alcohol. As the disease progresses, the hip joint needs to be replaced with an artificial joint. Risks with hip replacement surgery can include infection, implant dislocation, implant fracture and implant wear. The goal of this trial was to treat the disease with simple surgery using a drug called FGF. The surgical wound was 1 cm and the surgery took only 5 min. The results in 64 patients were better than in those without treatment. FGF treatment can be a therapeutic option for osteonecrosis of the femoral head.