Medical management of osteonecrosis of the hip: a review

New Technique of Reverse Bone Grafting With Core Decompression and Enriching With Regenerative Medicine Techniques for Grade 2 and Grade 3 Avascular Necrosis of Both Hips

Early avascular necrosis (AVN) of the hip poses a significant clinical challenge, requiring prompt recognition and intervention to mitigate long-term complications. A case report describing a 30-year-old man with bilateral hip AVN is presented here. In addition, to reverse bone grafting and core decompression of both hips, the patient had platelet-rich plasma (PRP) infiltration in the right hip and bone marrow aspirate concentrate (BMAC) infiltration in the left hip. This method attempted to stop the disease's development and promote hip regeneration in both. Significant pain reduction and postoperative functional gains in both hips are seen in this instance. These results highlight the potential of combined orthopedic and regenerative therapies in young individuals with hip AVN and highlight the necessity of early intervention for maintaining long-term hip function.

The efficiency of genetically modified mesenchymal stromal cells combined with a functionally graded scaffold for bone regeneration in corticosteroid-induced osteonecrosis of the femoral head in rabbits

Core decompression (CD) with mesenchymal stromal cells (MSCs) is an effective therapy for early-stage osteonecrosis of the femoral head (ONFH). Preconditioning of MSCs, using inflammatory mediators, is widely used in immunology and various cell therapies. We developed a three-dimensional printed functionally graded scaffold (FGS), made of β-TCP and PCL, for cell delivery at a specific location. The present study examined the efficacy of CD treatments with genetically modified (GM) MSCs over-expressing PDGF-BB (PDGF-MSCs) or GM MSCs co-over-expressing IL-4 and PDGF-BB and preconditioned for three days of exposure to lipopolysaccharide and tumor necrosis factor-alpha (IL-4-PDGF-pMSCs) using the FGS for treating steroid-induced ONFH in rabbits. We compared CD without cell-therapy, with IL-4-PDGF-pMSCs alone, and with FGS loaded with PDGF-MSCs or IL-4-PDGF-pMSCs. For the area inside the CD, the bone volume in the CD alone was higher than in both FGS groups. The IL-4-PDGF-pMSCs alone and FGS + PDGF-MSCs reduced the occurrence of empty lacunae and improved osteoclastogenesis. There was no significant difference in angiogenesis among the four groups. The combined effect of GM MSCs or pMSCs and the FGS was not superior to the effect of each alone. To establish an important adjunctive therapy for CD for early ONFH in the future, it is necessary and essential to develop an FGS that delivers biologics appropriately and provides structural and mechanical support.

Comparison of two joint-preserving treatments for osteonecrosis of the femoral head: core decompression and core decompression with additional cancellous bone grafting

OBJECTIVE

Femoral head necrosis (FHN) affects mostly young and active people. The most common operative therapy is core decompression (CD) with optional cancellous bone grafting (CBG). Because little information is available on the long-term results of these procedures, we investigated the effectiveness of CD and CD + CBG in patients with ARCO stage II FHN in terms of postoperative pain, range of motion, patient-reported outcome measures (Harris Hip Score, Hip Disability and Osteoarthritis Outcome Score, EuroQol 5D, and Short Form 36 Questionnaire), and disease progression.

METHODS

We retrospectively compared 11 patients treated with CD alone 48.0 months (range, 26.3-68.5 months) postoperatively versus 11 patients treated with CD + CBG 69.2 months (range, 38.0-92.9 months) postoperatively. All patients were assessed according to a routine clinical protocol involving a clinical examination, questionnaires, and radiological imaging (X-ray and magnetic resonance imaging).

RESULTS

The clinical and radiological results showed no significant differences between the two groups. Both interventions demonstrated equal results according to clinical scores.

CONCLUSIONS

Our data may encourage application of the less invasive technique of CD alone without CBG, which is more surgically demanding. Further prospective studies with longer follow-up are necessary to clarify the risk factors for therapy failure.

Avascular necrosis of the femoral head: three-dimensional measurement of drilling precision reveals high accuracy and no difference between fluoroscopically controlled core decompression and cancellous bone grafting

INTRODUCTION

Avascular osteonecrosis of the femoral head (AVN) is a widespread disease affecting mostly young and active people, often exacerbating in progressive stages, ending in joint replacement. The most common joint preserving operative therapy for early stages is core decompression (CD), optional with cancellous bone grafting (CBG). For success it is vital that the necrotic area is hit and the sclerotic rim is broken by drilling into the defect zone to relieve intraosseous pressure. The aim of this study was to investigate if both techniques are precise enough to hit the center of the necrosis and if there is a difference in precision between drilling with small pins (CD) and the trephine (CBG).

PATIENTS AND METHODS

10 patients underwent CD, 12 patients CBG with conventional C-arm imaging. Postoperatively 3D MRI reconstructions of the necrotic area and the drilling channels were compared. The deviation of the drilling channel from the center of the necrotic area was measured. PROMs (HHS, HOOS, EQ-5D, SF-36) were evaluated to compare the clinical success of these procedures.

RESULTS

Neither with CD nor with CBG the defect zone was missed. The drilling precision of both procedures did not differ significantly: distance to center 3.58 mm for CD (range 0.0-14.06, SD 4.2) versus 3.91 mm for CBG (range 0.0-15.27, SD 4.7). PROMs showed no significant difference.

CONCLUSION

Concerning the most important difference between the two procedures-the surgical higher demanding technique of CBG-we suggest applying the less invasive technique of CD alone.

Modulation of Differentiation and Bone Resorbing Activity of Human (Pre-) Osteoclasts After X-Ray Exposure

Low-dose radiotherapy (LD-RT) is a local treatment option for patients with chronic degenerative and inflammatory diseases, in particular musculoskeletal diseases. Despite reported analgesic and anti-inflammatory effects, cellular and molecular mechanisms related to osteoimmunological effects are still elusive. Here we test the hypothesis that X-irradiation inhibits the differentiation of precursor osteoclasts into mature osteoclasts (mOC) and their bone resorbing activity. Circulating monocytes from healthy donors were isolated and irradiated after attachment with single or fractionated X-ray doses, comparable to an LD-RT treatment scheme. Then monocytes underwent ex vivo differentiation into OC during cultivation up to 21 days, under conditions mimicking the physiological microenvironment of OC on bone. After irradiation, apoptotic frequencies were low, but the total number of OC precursors and mOC decreased up to the end of the cultivation period. On top, we observed an impairment of terminal differentiation, i.e. a smaller fraction of mOC, reduced resorbing activity on bone, and release of collagen fragments. We further analyzed the effect of X-irradiation on multinucleation, resulting from the fusion of precursor OC, which occurs late during OC differentiation. At 21 days after exposure, the observation of smaller cellular areas and a reduced number of nuclei per mOC suggest an impaired fusion of OC precursors to form mOC. Before, at 14 days, the nuclear translocation of Nuclear Factor Of Activated T Cells 1 (NFATc1), a master regulator of osteoclast differentiation and fusion, was decreased. In first results, obtained in the frame of a longitudinal LD-RT study, we previously reported a pain-relieving effect in patients. However, in a subgroup of patients suffering from Calcaneodynia or Achillodynia, we did not observe a consistent decrease of established blood markers for resorption and formation of bone, or modified T cell subtypes involved in regulating these processes. To assess the relevance of changes in bone metabolism for other diseases treated with LD-RT will be subject of further studies. Taken together, we observed that in vitro X-irradiation of monocytes results in an inhibition of the differentiation into bone-resorbing OC and a concomitant reduction of resorbing activity. The detected reduced NFATc1 signaling could be one underlying mechanism.

Comparisons of Ultrasound-Guided Platelet-Rich Plasma Intra-Articular Injection and Extracorporeal Shock Wave Therapy in Treating ARCO I–III Symptomatic Non-Traumatic Femoral Head Necrosis: A Randomized Controlled Clinical Trial

Background and Objective

Osteonecrosis of the femoral head (ONFH) is a devastating disease, and there is some evidence that extracorporeal shock wave therapy (ESWT) and intra-articular platelet-rich plasma (PRP) injection might alleviate pain and improve joint function in individuals with ONFH. The objective of this study was to compare the effectiveness and safety of PRP and ESWT in symptomatic ONFH patients.

Methods

A total of 60 patients aged 40–79 with unilateral ONFH at Association Research Circulation Osseous (ARCO) stages I, II, and III were randomly assigned to the PRP (N=30) or the ESWT group (N=30). Four treatment sessions were provided in both groups. Assessments were performed at baseline, and 1-, 3-, 6-, and 12-month. Primary outcomes were measured by the visual analogue scale (VAS), and pressure pain thresholds (PPTs). Secondary outcomes were assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), and magnetic resonance imaging (MRI). The linear mixed-model analysis was used to evaluate the differences between groups and within groups and the “group by time” interaction effects.

Results

There were significant differences between groups in terms of changes over time for VAS, PPTs, WOMAC, and HHS since 3-month and maintained up to 12-month (P<0.05, except for PPTs at 12-month). The simple main effects showed that the patients in PRP group had greater improvements in VAS (mean difference = −0.82, 95% CI [−1.39, −0.25], P=0.005), WOMAC (mean difference = −4.19, 95% CI [−7.00, −1.37], P=0.004), and HHS (mean difference = 5.28, 95% CI [1.94, 8.62], P=0.002). No related adverse events were reported.

Conclusion

This study supported the effectiveness and safety of both the PRP injection and ESWT in treating ONFH patients. For symptomatic patients with ONFH, intra-articular PRP injection appeared superior to ESWT in pain relief and functional improvement.

Operative Management of Avascular Necrosis of the Femoral Head in Skeletally Immature Patients: A Systematic Review

Purpose: Osteonecrosis of the femoral head (ONFH) is common in skeletally immature patients. The management of ONFH is controversial, with limited evidence and unpredictable results. This study systematically reviewed the current operative modalities and clinical outcomes of surgical management for ONFH in skeletally immature patients. Methods: The present study was conducted according to the PRISMA 2020 guidelines. PubMed, Google Scholar, Embase, and Web of Science databases were accessed in October 2021. All the published clinical studies reporting data concerning the surgical management of ONFH in skeletally immature patients were included. Results: This review included 122 patients (127 hips). 38.2% (46 of 122) were female. The mean age of the patients was 14.2 ± 2.3 years. The mean duration of the follow-up was 55.3 ± 19.6 months. The Harris Hip Score improved from 68.8 ± 11.9 at baseline to 90.5 ± 6.5 at last follow-up (p < 0.0001). Femoral head collapse and secondary hip degeneration were the most common complications. Conclusion: Several surgical techniques are available and effective for the management of ONFH in skeletally immature patients. This study evidenced high heterogeneity of the surgical procedures and eligibility criteria. Further high-quality investigations are required to establish proper indications and surgical modalities.

Aseptic Necrosis of Femoral Head - Clinical Study

Femoral head osteonecrosis is a disease characterized by the decrease of blood vascularization in the femoral head, which leads to death of the osteocytes, demineralization and resorption of bone spans, change of trabecular architecture, with the reduction of the bone mechanical resistance and collapse of the articular surface in the femoral head. Left untreated, the disease may have a rapid progression, leading to severe symptoms, with significant articular dysfunction, functional impotence and a serious impact on the patient’s quality of life. The prevalence of the disease is ever growing all over the world, affecting mainly people in their 30s, 40s or 50s. In the present study, we analyzed a number of 76 patients with femoral head osteonecrosis with severe symptoms that required a surgical treatment. There was observed that more than ¾ of the investigated patients were males, while 81.58% were younger than 60 years old. Among the identified risk factors, smoking came first, followed by alcohol intake, obesity and chronic administration of corticosteroids. A very high percentage of patients (84.21%) were diagnosed in stages III and IV of the disease.

Effect on Osteogenic Differentiation of Genetically Modified IL4 or PDGF-BB Over-Expressing and IL4-PDGF-BB Co-Over-Expressing Bone Marrow-Derived Mesenchymal Stromal Cells In Vitro

The use of genetically modified (GM) mesenchymal stromal cells (MSCs) and preconditioned MSCs (pMSCs) may provide further opportunities to improve the outcome of core decompression (CD) for the treatment of early-stage osteonecrosis of the femoral head (ONFH). GM interleukin-4 (IL4) over-expressing MSCs (IL4-MSCs), platelet-derived growth factor (PDGF)-BB over-expressing MSCs (PDGF-BB-MSCs), and IL4-PDGF-BB co-over-expressing MSCs (IL4-PDGF-BB-MSCs) and their respective pMSCs were used in this in vitro study and compared with respect to cell proliferation and osteogenic differentiation. IL4-MSCs, PDGF-BB-MSCs, IL4-PDGF-BB-MSCs, and each pMSC treatment significantly increased cell proliferation compared to the MSC group alone. The percentage of Alizarin red-stained area in the IL4-MSC and IL4-pMSC groups was significantly lower than in the MSC group. However, the percentage of Alizarin red-stained area in the PDGF-BB-MSC group was significantly higher than in the MSC and PDGF-BB-pMSC groups. The percentage of Alizarin red-stained area in the IL4-PDGF-BB-pMSC was significantly higher than in the IL4-PDGF-BB-MSC group. There were no significant differences in the percentage of Alizarin red-stained area between the MSC and IL4-PDGF-BB-pMSC groups. The use of PDGF-BB-MSCs or IL4-PDGF-BB-pMSCs increased cell proliferation. Furthermore, PDGF-BB-MSCs promoted osteogenic differentiation. The addition of GM MSCs may provide a useful supplementary cell-based therapy to CD for treatment of ONFH.

Avascular necrosis of the first metatarsal head in a young female adult: A case report and review of literature

BACKGROUND

This case study describes an atypical presentation of avascular necrosis (AVN) of the first metatarsal head, which is largely unfounded in the literature.

CASE SUMMARY

A healthy 24-year-old female initially presented with pain at the first metatarsophalangeal joint (MTPJ) and was diagnosed with AVN by physical examination and magnetic resonance imaging. The patient demonstrated atypically poor progress in recovery, despite being in otherwise good health and being of young age, with no history of corticosteroid or alcohol use. The patient also did not have any history or clinical features of autoimmune disease or vasculitis, such as systemic lupus erythematosus. The patient was managed with conservative treatment for 18 mo, which allowed for gradual return of full range of motion of the first MTPJ and subsiding pain, permitting the patient to return to high-intensity sports training and full weight-bearing. Throughout her recovery, many differential diagnoses were ruled out through specific investigations leading to further reinforcement of the diagnosis of AVN of the 1^st metatarsal head.

CONCLUSION

Atypical AVN may occur with no predisposing risk factors. Treatment is mainly conservative, with unclear guidelines in literature on management.

Extracorporeal Shockwave Therapy Modulates the Expressions of Proinflammatory Cytokines IL33 and IL17A, and Their Receptors ST2 and IL17RA, within the Articular Cartilage in Early Avascular Necrosis of the Femoral Head in a Rat Model

Avascular necrosis (AVN) of the femoral head (AVNFH) is a disease caused by injury to the blood supply of the femoral head, resulting in a collapse with osteonecrosis and damage to the articular cartilage. Extracorporeal shockwave therapy (ESWT) has been demonstrated to improve AVNFH owing to its anti-inflammation activity, angiogenesis effect, and tissue regeneration in clinical treatment. However, there are still so many pieces of the jigsaw that need to be fit into place in order to ascertain the mechanism of ESWT for the treatment of AVNFH. The study demonstrated that ESWT significantly protected the trabecular bone volume fraction BV/TV (P < 0.01) and the trabecular thickness (P < 0.001), while in contrast, the trabecular number and trabecular separation were not significantly different after treatment as compared with AVNFH. ESWT protected the articular cartilage in animal model of AVNFH. The levels of IL1-β and IL33 were significantly induced in the AVNFH group (P < 0.001) as compared with Sham and ESWT groups and reduced in ESWT group (P < 0.001) as compared with AVNFH group. In addition, the expression of the receptor of IL33, ST2, was reduced in AVNFH and induced after ESWT (P < 0.001). The expression of IL17A was induced in the AVNFH group (P < 0.001) and reduced in the ESWT group (P < 0.001). Further, the expression of the receptor of IL17A, IL17RA, was reduced in the AVNFH group (P < 0.001) and improved to a normal level in the ESWT group as compared with Sham group (P < 0.001). Taken together, the results of the study indicated that ESWT modulated the expression of IL1-β, pro-inflammatory cytokines IL33 and IL17A, and their receptors ST2 and IL17RA, to protect against loss of the extracellular matrix in the articular cartilage of early AVNFH.

Avascular femoral necrosis as part of Cushing syndrome presentation: a case report

Background

The clinical characteristics and complications of Cushing syndrome (CS) are well known and described in the literature. Nevertheless, rare, atypical presentations may go unnoticed. Osteonecrosis is a well-documented complication of glucocorticoid therapy. However, endogenous hypercortisolism is a rare, but relevant, cause of bone avascular necrosis. We describe the case of a woman with CS undiagnosed for 2 years after presenting with femoral avascular necrosis.

Case presentation

A 38-year-old Caucasian woman was referred for evaluation of secondary amenorrhea, associated with oral contraception withdrawal in the context of deep venous thrombosis (DVT). She had a previous right hip arthroplasty for treatment of avascular necrosis of the femoral head, diagnosed after 3 years of progressive right hip pain and limited mobility. She also had high blood pressure (HBP) of 5 years’ duration, and reported weight gain (4 kg in 2 years). There was no history of infertility (gravida 2, para 2). Physical examination revealed buffalo hump, truncal obesity, facial plethora, muscular atrophy and proximal myopathy, and easy bruising (under anticoagulant treatment for DVT). Workup showed abnormal overnight dexamethasone suppression test (DST) (serum cortisol 21.5 µg/dL; normal < 1.8 µg/dL), elevated 24-hour urinary free cortisol (UFC) (728.9 µg/day; reference range 36.0–137.0 µg/day), and suppressed plasma adrenocorticotropic hormone (ACTH) (< 1.0 pg/mL), findings consistent with ACTH-independent CS. Urinary metanephrines and catecholamines were normal, and the remaining analytical study showed no major changes, apart from glycated hemoglobin (HbA1c) of 6.8%. Adrenal computed tomography (CT) scan showed a 25 mm lesion in the left adrenal gland, with density non-suggestive of adenoma. The patient underwent unilateral adrenalectomy and started steroid replacement. Histology revealed an adrenal cortex adenoma. Three months after surgery the patient presented with resolution of HBP and hypercortisolism (UFC 37.4 µg/day; reference range 36.0–137.0 µg/day).

Conclusion

In some cases, CS signs may go unnoticed and the diagnosis postponed. Avascular necrosis is a rare presenting feature of endogenous hypercortisolism, and, if left untreated, complete collapse of the femoral head may ensue, rendering the need for hip replacement in up to 70% of patients. Suspicion and recognition of atypical features is therefore important in avoiding complications and delay in treatment of CS.

PPARGC1B Is Associated with Nontraumatic Osteonecrosis of the Femoral Head: A Genomewide Association Study on a Chart-Reviewed Cohort

BACKGROUND

Previous studies have demonstrated the influence of heritable factors on the development of nontraumatic osteonecrosis of the femoral head (ONFH). We hypothesized that genetic variation is associated with an increased risk of ONFH, and that variants could be identified by a genomewide association study (GWAS).

METHODS

Using data collected from the MyCode Community Health Initiative, we identified 118 adult patients with radiographically confirmed nontraumatic ONFH. Study patients were statistically compared with a control population of 56,811 unrelated individuals without a diagnosis of ONFH. A case-control GWAS was performed to identify single nucleotide variants (SNVs) associated with ONFH. Sensitivity analyses were performed to evaluate the association of the top SNVs with (cortico)steroid-associated ONFH and ONFH with femoral head collapse. Gene-based analyses were performed to identify potential causal genes.

RESULTS

Of the 118 patients, 114 (96.6%) had bilateral ONFH at a median of 5 years of follow-up; 90.7% had at least one 3-week steroid prescription compared with 68.3% in controls. A GWAS identified 4 SNVs reaching genomewide significance. rs116468452 near CACNA1E was significantly associated with ONFH (p = 3.26 × 10, odds ratio [OR] = 5.6, 95% confidence interval [CI] = 3.21 to 9.76). rs10953090 in SAMD9 was significantly associated with ONFH in the steroid-exposed subset (p = 2.96 × 10, OR = 2.57, 95% CI = 1.84 to 3.58). rs112467115 in PI4K1B showed enhanced association in the collapsed subset (p = 7.82 × 10, OR = 4.5, 95% CI = 2.60 to 7.79). Gene-based analyses identified PPARGC1B as the only gene significantly associated with ONFH after Bonferroni correction (p = 1 × 10), with the lead SNV being rs78814834 (OR = 2.86, 95% CI = 1.87 to 4.38).

CONCLUSIONS

We identified 4 SNVs and 1 gene, PPARGC1B, associated with ONFH.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Simultaneous Bilateral Avascular Necrosis of the Femoral Heads Associated With Cocaine Use

We present a case of a 38-year-old female patient, presenting with debilitating simultaneous bilateral avascular necrosis of the femoral head (AVNFH) 10 years after cocaine detoxification, making her wheelchair-bound for six months. This case is reported for the rarity of association of cocaine with AVNFH, and for the unique fact of the simultaneous bilateral condition occurring a long time after cocaine ingestion in the absence of other important risk factors.

This report postulates cocaine as a possible cause of bilateral AVNFH, which can increase the index of suspicion of this pathology, allowing early diagnosis and better outcomes.

Histopathological Signatures of the Femoral Head in Patients with Osteonecrosis and Potential Applications in a Multi-Targeted Approach: A Pilot Study

(1) Background: Osteonecrosis (ON) of the femoral head is a disabling disease for which limited treatment options exist. Identifying therapeutic targets of its evolution could provide crucial insights into multi-targeted approaches. The aim of this pilot study was to assess the histopathological features of patients with non-traumatic femoral head (NTFH) and post-traumatic femoral head (PTFH) ON to produce a fresh vision for clinical use. (2) Methods: We got biopsies from patients with different ON stages, according to the ARCO system. Samples from multi-organ donors were used as controls. Histological and immunohistochemical evaluations were performed on the osteochondral unit. (3) Results: The PTFH group displayed several fibrotic reactions, a small stem cell pool and a lower international cartilage repair society (ICRS)-I score than NTFH, which instead presented intact cartilage similar to the controls. Immunostaining for collagen I and autotaxin confirmed these features in the PTFH group, which displayed top levels of MMP-13 involved in cartilage loss and reduced CB-2 in the underlying bone. Both groups manifested a similar pattern of apoptotic and pain mediators. (4) Conclusions: The different histopathological features suggest a multi-disciplinary and multi-targeted approach for ON. Further studies are necessary to measure the effect size to gain clinical evidence.

Core Decompression Combined with Implantation of Autologous Bone Marrow Concentrate with Tricalcium Phosphate Does Not Prevent Radiographic Progression in Early Stage Osteonecrosis of the Hip

Backgroud

Untreated osteonecrosis of the femoral head ultimately leads to secondary coxarthrosis. The aim of this study was to determinate if the core decompression of the femoral head combined with implantation of autologous bone marrow concentrate with tricalcium phosphate could be used to prevent radiographic progression of early stage osteonecrosis of the hip. We also sought to determine whether this treatment improved clinical outcomes and reduced the need for total hip arthroplasty.

Methods

Eighteen hips were included in the present study. All of them underwent core decompression of the femoral head combined with implantation of autologous bone marrow concentrate with tricalcium phosphate between 2007 and 2012. The cell concentrate was obtained from the posterior iliac crest and processed and implanted during the same surgical procedure. Patient demographic data, clinical data including modified Harris hip score, and radiological data were collected preoperatively, postoperatively, and during the follow-up period. Also, survival endpoints were analyzed: time of femoral head collapse and need for total hip arthroplasty.

Results

The mean age of patients was 37.8 years (standard deviation [SD], 9.31 years). The mean follow-up was 68.9 months (SD, 15.0 months). In most cases (70.6%), the etiology of the osteonecrosis of the femoral head was corticosteroid use; in the remaining cases, secondary to alcohol use. Core decompression of the femoral head combined with implantation of autologous bone marrow concentrate with tricalcium phosphate did not prevent progression to collapse (< 80% at 5 years) although modified Harris hip scores improved. Overall median survival with the total hip arthroplasty as endpoint was 23 months (95% confidence interval [CI], 14.9 to 31.1 months). Overall median survival time with any degree of collapse as endpoint was 7 months (95% CI, 2.0 to 12.0 months).

Conclusions

The results obtained in this study suggest that core decompression combined with implantation of autologous bone marrow concentrate and tricalcium phosphate will not prevent radiographic progression of early stage osteonecrosis of the hip. These finding also suggest that the absence of indications for hip replacement alone is not an indicator of good response to the treatment, and it is important to note the radiological results.

Treatment of avascular osteonecrosis of femoral head by core decompression and platelet-rich plasma: a prospective not controlled study

PURPOSE

Core decompression is a surgical option since the 1960s for hip osteonecrosis treatment. This technique promotes bone repair by reducing intramedullary pressure, but this is not often enough to stop the progression of necrosis. The aim of this study was to associate core decompression with the regenerative stimulus provided by platelet-rich plasma (PRP) and compare our results with other regenerative techniques.

METHODS

Femoral head osteonecrosis was prospectively evaluated in 30 hips (22 patients, 15-60 years) treated by core decompression and PRP graft. Patients presented monolateral or bilateral osteonecrosis in stage I-IIA-IIB according to Arlet and Ficat classification. The outcome was assessed by changes in Harris Hip Score (HHS) and the need for total hip replacement (THA).

RESULTS

The mean preoperative HHS was 64 points, at two years from surgery was roughly 84 points. Sixteen of 30 hips showed osteonecrosis progression of the femoral head and were converted to THA. At the five year follow-up, the survival rate was 100% for patients at stage I, 67% for stage IIA, and 0% for stage IIB and was 68% and 32% for idiopathic and secondary osteonecrosis, respectively.

CONCLUSION

Core decompression combined with PRP could be indicated as a treatment for the I and IIA stages of osteonecrosis, as it significantly reduces joint pain and delays THA. This procedure should be avoided in AVNFH related to cortisone therapy because only a few benefits have been proven. It also has the advantage of being technically simple, minimally invasive, and free from complications.

Comparison of core decompression and porous tantalum rod implantation with conservative treatment for avascular necrosis of the femoral head: A minimum 18 month follow-up study

Porous tantalum rod implantation is a novel surgical method that is used to treat avascular necrosis (AVN) of the femoral head (hip). In the present study, the results of core decompression and tantalum rod implantation were compared with non-surgical treatment for AVN, and the survivorship of the femoral head was evaluated. In total, 60 patients with AVN femoral head were recruited and analysed. Non-surgical treatment was selected by 30 patients (41 hips), 7 with a Ficat score of I and 23 with a score of II. Non-surgical treatment included celecoxib, salvia miltiorrhiza and tetramethylypyrazine and a reduction in weight-bearing activities. Surgical treatment and porous tantalum rod implantation were selected by 30 patients (41 hips), 10 with a Ficat score of I and 20 with a score of II. After follow-up (average: 33.5 months), patients were evaluated by assessing post-operative complications, radiology, hip survivorship and Harris hip score. In the surgical group, pre-operative symptoms were significantly alleviated. No complications, including infection, delayed healing or fractures were reported. Final follow-up rates of femoral head survivorship were 4.9% in the non-surgical group and 36.7% in the surgical group. The Harris hip score was significantly improved following surgery when compared with non-surgical treatment (P<0.05). The results indicated that core decompression and porous tantalum rod implantation are beneficial short- and mid-term treatment methods for AVN of the femoral head.

Avascular necrosis: radiological findings and main sites of involvement - pictorial essay

The term avascular necrosis describes any one of a number of bone diseases that have a common mechanism: the death of bone components due to lack of blood supply. Avascular necrosis can occur in diverse parts of the skeleton, each location-specific form not only receiving a distinct designation but also presenting unique epidemiologic characteristics. However, the imaging findings are similar in all of the forms, which pass through well-described radiological phases, regardless of the site of involvement. Because avascular necrosis can cause considerable morbidity if not properly detected and managed, the radiologist plays a fundamental role. The present study provides a brief review of the main radiological aspects of the various forms of avascular necrosis, illustrated on the basis of a collection of cases from our institution.

Angiogenesis and bone regeneration by mesenchymal stem cell transplantation with danshen in a rabbit model of avascular necrotic femoral head

The present study aimed to explore the potential of combined treatment with mesenchymal stem cells (MSCs) and danshen for angiogenesis and bone regeneration in a rabbit model of avascular necrosis of femoral head (ANFH). A rabbit model of ANFH was established using the Shwartzman reaction with methylprednisolone and Escherichia coli endotoxin injection. Magnetic resonance imaging (MRI) and histopathological examination were used to evaluate the rabbit model of ANFH. The rabbits were randomly divided into the danshen group, the MSCs group, the danshen combined with MSCs group and the model group (treated with physiological saline). The expression level of monocyte chemoattractant protein-1 (MCP-1) and stromal cell-derived factor-1 (SDF-1) were determined by reverse transcription polymerase chain reaction (RT-PCR). The expression level of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) were detected by immunofluorescence and the mRNA expression of BMP-2 and VEGF were detected by RT-PCR. Typical osteonecrosis occurred in the rabbit model of ANFH, which indicated that the model was successfully established. MCP-1 and SDF-1 were significantly increased in the model group compared with the normal group (P<0.05). Following the administration of MSCs and Salvia miltiorrhiza (danshen), MSCs labeled with 5-bromo-2-deoxyuridine were observed to be gathered in the necrotic area. The increased migration of MSCs to the necrotic area may be due to the upregulated expression of the chemokines MCP-1 and SDF-1. ANFH treated with danshen combined with MSCs may promote revascularization by increasing the expression of VEGF and BMP-2 in the femoral head, promoting re-ossification and revascularization. Danshen combined with the transplantation of MSCs may be regarded as a novel therapy for the treatment of ANFH in a clinical setting.

Avascular Necrosis of the Tibial Plafond Following Rotational Ankle Fractures

Avascular necrosis (AVN) following rotational ankle fractures is most commonly described in the talus; however, it can also occur in the tibial plafond. These sequelae of ankle fractures are rarely described in the literature. Diagnosis of AVN is best confirmed with MRI of the involved extremity. Treatment options range from conservative treatments such as observation and limited weight-bearing to surgical management including percutaneous drilling, ankle arthrodesis, and total ankle arthroplasty. More research is needed to further identify patients at high risk for developing these sequelae of ankle fractures and to aid in the treatment and surgical decision-making process.

Clinical characteristics of avascular necrosis in patients with Behçet disease: a case series and literature review

Avascular necrosis (AVN), also known as osteonecrosis, is characterized by death of the osteocytes due to inadequate blood supply caused by various mechanisms. The hip is the most common affected joint followed by knee. Incidence of AVN in rheumatic diseases is variable and high corticosteroid (CS) therapy is a known major risk factor for development of AVN. Data on the AVN in Behçet disease (BD) are limited. The purpose of this study is to examine the clinical and treatment characteristics of BD patients with diagnosis of AVN. Retrospective medical records of 337 BD patients were reviewed. Nine BD patients with AVN were detected. The clinical data of these patients with AVN have been reviewed. All patients had MRI of the symptomatic joints compatible with AVN. All of the nine patients who were diagnosed with AVN were male. Median duration of BD was 7 years. Median time between diagnosis of BD and detection of AVN was 3 years (1-16 years). Multiple joints were involved in seven patients. Six patients had bilateral knee AVN. Six patients had vascular BD. The median time interval between initial CS dose and AVN development was 24 months (range = 2-100). The median highest daily CS dose was 64 mg/day (range = 32-80) and median cumulative CS dose prior to AVN was 18 g. All of patients had intravenous pulse steroids. CS treatment, smoking and vascular involvement may predispose to AVN in patients with BD. According to this cohort, AVN in BD frequently tended to be in the knee joint and bilateral.

Biomechanical bearing-based typing method for osteonecrosis of the femoral head: ABC typing

Type classification of osteonecrosis of the femoral head (ONFH) is important for collapse prediction in ONFH, which depends on a complexity of factors. At present, most typing is based on single factors, including the location or size of the necrosis, or the bone repair capacity after ONFH, and is therefore limited. The present study proposes an 'ABC' method for ONFH typing based on biomechanics and the stress distribution characteristics of the femoral head's bone trabeculae. In total, 132 ONFH patients (223 hips) were enrolled at Guanganmen Hospital (Beijing, China). Each of the hip joints included was subjected to computerized tomography and/or magnetic resonance imaging. The images with the maximum necrotic area in the coronal femoral head were selected, and the femoral head's maximum transverse diameter was divided into three pillars (A, B and C, from the outside to the inside) according to a 3:4:3 diameter ratio. ONFH was typed according to the number of pillars involved in the necrosis. Differences in the collapse rate of different ONFH types, and the correlation between the theoretical collapse risk and the observed collapse rate was analysed. The ONFH types significantly differed in their collapse rate (χ²=76.93, P<0.001) in the following order: A-C (88.6%)>AB (74.1%)>BC (52.4%)>A (50%)>B (9.5%)>C (0%). The collapse risk was significantly correlated with the collapse rate (correlation coefficient R=1). The types A-C and AB had high collapse rates/risks, whereas types B and C had a satisfactory prognosis. The ABC typing proposed in the present study is thus suitable for collapse risk prediction in ONFH. Type classification using this method may provide a valuable reference for selecting regimens for ONFH treatment.

A CARE-compliant article: Biomechanics of treating early-stage femoral-head osteonecrosis by using a β-tricalcium phosphate bioceramic rod system: a 3-dimensional finite-element analysis

The effect of implanting a β-TCP bioceramic rod system (BRS) can be observed with using the 3-dimensional (3D) finite-element method on the biomechanics of early-stage osteonecrosis of the femoral head (ONFH), to provide a theoretical basis for the biomechanics of applying the β-TCP BRS in the treatment of ONFH.A healthy 172 cm tall male adult volunteer (age: 40 years, weight: 70 kg, and femoral diameter: 50 mm) was selected for this study. The volunteer had no history of diseases in the hip, lower back, and lower limbs. He also had no history of trauma and surgery and had no lesions in the femoral head.A finite-element model of the normal proximal femur was constructed, and on this basis, 4 ONFH finite-element models were constructed, which had 15% and 30% necrotic areas in the superolateral area and 2 and 4 mm collapse in the weight-bearing area of the femoral head, respectively.This process was followed by simulated implantation of the β-TCP BRS in the finite-element models of the femoral head. Changes in the stress and displacement of the femoral head were observed before and after treatment with the β-TCP BRS, and the risk of femoral-head collapse was assessed.Under an applied walking load, the stress concentration on the femoral head was alleviated after treatment. Moreover, the stress and collapse values of the weight-bearing area decreased compared with those before treatment, and the differences were statistically significant (P < .05); the risk of collapse was also lower than that before treatment. As the area of the necrosis increased, the collapse value also increased, and the risk of collapse increased. More severe preoperative collapse implied that a greater risk of postoperative recollapse exists.This case report was written for 4 purposes: Implantation of the β-TCP BRS could effectively improve the internal mechanical properties of ONFH, enhance the support capacity of bones in the weight-bearing area in ONFH, reduce the compressive stress on the necrotic bone, and lower the risk of collapse in ONFH.

Clinical value of 3D printing guide plate in core decompression plus porous bioceramics rod placement for the treatment of early osteonecrosis of the femoral head

BACKGROUND

The conventional method of core decompression combined with porous bioceramics rod is usually performed under C-arm fluoroscopy for the treatment of early osteonecrosis of the femoral head (ONFH). This study was to evaluate the clinical value and efficacy of three-dimensional (3D) printing guide plate in the process of core decompression plus porous bioceramics rod for the treatment of early ONFH.

METHODS

Forty patients were enrolled, including 20 patients undergoing the surgery with 3D printing guide plate in the experiment group and 20 controls with C-arm fluoroscopy. The following parameters such as surgery time, blood loss, fluoroscopy times, and the accuracy of core decompression for necrosis area, function outcome according to Harris Hip Score (HHS), and any possible complications were recorded and compared between the two groups. All the patients were followed up at 6, 12, and 18 months postoperatively.

RESULTS

The surgery time, fluoroscopy time, and intraoperative blood loss in the experiment group was significantly less (P < 0.05) than those in the control group. There was no statistical significance in the accuracy of core decompression and porous bioceramics rod placement between the two groups (P > 0.05). All patients were followed up for 18 months. There was a significant difference between the preoperative and final follow-up HSS scores in both groups (P < 0.05). In addition, there was also a significant difference between the groups in the last follow-up HSS scores (P < 0.05).

CONCLUSIONS

Compared with the traditional method, 3D printing guide plate could shorten the surgery time and fluoroscopy times and decrease intraoperative blood loss. It seems to be an effective method in the combined core decompression with porous bioceramics rod placement for early ONFH.

Lightbulb technique for the treatment of osteonecrosis of the femoral head

INTRODUCTION

The aim of this study was to report the clinical and radiological outcomes for 21 patients (28 hips) treated for osteonecrosis of the femoral head using the lightbulb technique, a nonvascularised bone grafting technique.

METHODS

The study group included 14 men and 7 women, with a mean age of 33.2 (range 22-50) years, presenting with avascular necrosis of the femoral head of stage 4a or earlier, according to the Steinberg classification. Patients were treated using the nonvascularised lightbulb bone grafting technique. The primary clinical outcome was the Harris Hip Scores (HHS), while primary outcomes of treatment effectiveness and disease progression were based on radiographic evidence of disease progression and the need for total hip replacement. The rate of treatment success and failure was evaluated using the Kaplan-Meier survival analysis.

RESULTS

The mean HHS increased from 52.66 to 74.33 after treatment, with excellent-to-good outcomes obtained in 21 (75%) of the cases. Fair-to-poor results were obtained in 7 (25%) of the cases, with total hip arthroplasty subsequently required in 5 of these cases. The radiological failure rate was 50% among cases treated in Steinberg stage 1 (1/2), 42% in stage 3 (5/12), and 100% in stage 4 (2/2).

CONCLUSIONS

The lightbulb technique can provide a clinically acceptable rate of successful treatment of osteonecrosis of the femoral head when used in the early stages of the disease, prior to collapse of the femoral head.

The use of anticoagulants for prevention and treatment of osteonecrosis of the femoral head: A systematic review

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a progressive disease, which mainly affects young adults and often necessitates total hip arthroplasty (THA), so early interventions are critical to successfully protect hip joint from THA. In this review, our purpose was to determine the effects of anticoagulants for preventing and treating the primary and secondary ONFH, respectively, before the collapse stage or before the pathology of necrosis.

METHODS

We searched PubMed, Embase, Web of Science databases for relevant studies. Any observational or experimental studies that evaluated anticoagulants and ONFH were our goal of searching the electric databases.

RESULTS

Four studies including a total of 218 hips were identified in this review, 2 of them were prospective studies which performed by 1 group, 1 was a retrospective study, and the last was a prospective comparative study.

CONCLUSIONS

Our findings supported that the anticoagulants could be used for primary ONFH. However, anticoagulants cannot play a protective role on secondary ONFH. Moreover, there were no serious adverse effects reported in the studies after anticoagulants treatment. Nevertheless, our present study with some limitations such as the limited sample size only provided limited quality of evidence; confirmation from further systematic review or meta-analysis with large-scale, well-designed randomized control trials is required.

Atypical Clinical Presentation of Rapidly Progressing Femoral Head Avascular Necrosis

A 51-year-old man presented to an urgent care facility 2 weeks after onset of left lateral hip and buttock pain. Radiographs were noncontributory. An orthopaedist referred him to physical therapy, but due to the worsening clinical presentation, he was referred back to the orthopaedist for additional evaluation. Magnetic resonance imaging was ordered and demonstrated abnormal femoral head and acetabular contour, extensive bone marrow edema, and a complex joint effusion. He was diagnosed with femoral head avascular necrosis. J Orthop Sports Phys Ther 2017;47(3):217. doi:10.2519/jospt.2017.6483.

Inverted femoral head graft versus standard core decompression in nontraumatic hip osteonecrosis at minimum 3 years follow-up

PURPOSE

Numerous salvage surgeries were popularised to halt the progression of hip osteonecrosis (ON). We aimed to compare the clinico-radiological outcomes of inverted femoral head graft (IFHG) versus standard core decompression (SCD) in treatment of nontraumatic hip ON at pre-arthritic stage.

METHODS

A case review was performed at a minimum 3 years follow-up of 61 patients (71 hips; mean age 32.96 (19-50) years; mean follow-up 7.86 (3-14) years; mean body mass index 28.58 (19-46); 32 males, 29 females) suffering nontraumatic hip ON at pre-arthritic stage. 38 hips underwent SCD and 33 IFHG. The outcome was assessed by changes in modified Harris Hip Score (MHHS), need for revision surgery and progression of modified Ficat-Arlet staging. Data were analysed including logistic regression and Kaplan-Meier survivorship analysis.

RESULTS

13/34 (38.2%) hips in SCD group were revised at 4.61 ± 2.61 years, while 7/33 (21.2%) in IFHG group at 8.43 ± 4.32 years (p = 0.023). MHHS was significantly higher in IFHG group at 1 and 3 years as well as at last follow-up (p = 0.014, 0.001 and 0.023 respectively). Clinical and radiological significant differences were found in survivorship analysis between both groups, in favor of IFHG. A higher clinical failure was noted among obese patients.

CONCLUSIONS

An IFHG technique offers a better alternative regarding postoperative clinico-radiological outcomes in nontraumatic hip ON at the pre-arthritic stage. A cautious prognosis is recommended in obese patients.

Nontraumatic Osteonecrosis of the Distal Tibia: A Case Presentation and Review of the Literature

Osteonecrosis, although commonly occurring in the hip, can also affect the leg and foot. In the foot, it most commonly occurs in the talus. The incidence of osteonecrosis occurring in the tibia is relatively rare. We report a case of a woman who presented to our clinic with ankle pain that was idiopathic in nature. Subsequent magnetic resonance imaging showed findings consistent with osteonecrosis of the bilateral distal tibias and several other lesions located in the shoulder, hip, and calcaneus. The present report also serves as a review of both etiology and treatment of osteonecrosis as it relates to the lower extremity.

Mid-term comparative outcomes of autologous bone-marrow concentration to treat osteonecrosis of the femoral head in standard practice

PURPOSE

To evaluate mid-term effectiveness of core decompression (CD) followed by injection of bone-marrow concentration (BMC) in osteonecrosis of the femoral head (ONFH) compared with CD alone.

METHODS

We retrospectively studied 60 hips in 45 patients with ONFH Ficat I-II after a mean follow-up of 45 (range 24-171) months. Group A (19 hips) were treated with CD, and Group B (41 hips) with CD plus autologous BMC. Necrotic lesions were classified according to MRI findings in: (i) the lesion angle; and (ii) the relation of the necrotic area to the weight-bearing portion. Outcomes included clinical changes and radiographic femoral head collapse. Risk factors associated with radiological collapse were evaluated by Cox regression analysis.

RESULTS

Postoperative Merlé D´Aubigne and Postel hip score was similar in both groups. Femoral head collapse was observed in 10/19 hips in Group A and 22/41 in Group B. At 24 months, the probability of not having a collapse was 56.4% (95% CI, 33.6%-79.1%) for Group A and 57.6% (95% CI, 41.7%-73.4%) for Group B (p = 0.47). The risk of collapse increased in hips with a lesion angle higher than 150° (p&lt;0.02, hazard risk [HR] 4.073) in both groups.

CONCLUSIONS

With the standard BMC technique performed without monitoring the number of progenitors in the concentrate, we are uncertain to observe a significant decrease in femoral head collapse compared to CD alone. Improved outcomes may require the monitoring of progenitor cells injected into the femoral head, particularly in large lesions.

Common factors associated with osteonecrosis of the femoral head in young patients requiring total hip arthroplasty

Osteonecrosis of the femoral head is a pathologic condition that commonly affects young patients and requires treatment with total hip arthroplasty (THA). The most common factors associated with osteonecrosis in young patients have not been previously described in the literature. A retrospective study was conducted to describe the most common factors associated with osteonecrosis in patients aged 35 or younger requiring a primary THA. This study included 235 patients and found that the most common factor associated with osteonecrosis was corticosteroid use (61%), followed by idiopathic causes (11%), trauma (9%), other causes (8%), haemoglobinopathies (7%), and alcoholism (3%). There was no significant difference in age between risk groups (p-value = 0.35), however there were significant differences in sex (p-value = 0.02) and unilateral versus bilateral surgery (p-value<0.01). Several factors are associated with the development of osteonecrosis of the femoral head in young patients, and these factors should be given consideration in determining disease aetiology and counselling patients.

Nontraumatic Osteonecrosis of the Femoral Head: Where Do We Stand Today? A Ten-Year Update

➤ Although multiple theories have been proposed, no one pathophysiologic mechanism has been identified as the etiology for the development of osteonecrosis of the femoral head. However, the basic mechanism involves impaired circulation to a specific area that ultimately becomes necrotic.➤ A variety of nonoperative treatment regimens have been evaluated for the treatment of precollapse disease, with varying success. Prospective, multicenter, randomized trials are needed to evaluate the efficacy of these regimens in altering the natural history of the disease.➤ Joint-preserving procedures are indicated in the treatment of precollapse disease, with several studies showing successful outcomes at mid-term and long-term follow-up.➤ Studies of total joint arthroplasty, once femoral head collapse is present, have described excellent outcomes at greater than ten years of follow-up, which is a major advance and has led to a paradigm shift in treating these patients.➤ The results of hemiresurfacing and total resurfacing arthroplasty have been suboptimal, and these procedures have restricted indications in patients with osteonecrosis of the femoral head.

Fast sequences MR imaging at the investigation of painful skeletal sites in patients with hip osteonecrosis

BACKGROUND

Multiple osteonecrotic foci can be clinically silent when located in metaphyses and becomes painful when it affects juxta-articular areas. The purpose of this study was to assess the value of fast MR imaging to depict the underlying pathology in cases with skeletal pain other than the already diagnosed hip osteonecrosis.

METHODS/DESIGN

Between 2008 and 2013, 49 patients with already diagnosed hip osteonecrosis reported symptoms of deep skeletal pain in an anatomical site different from the affected hip joint. All patients after thorough history & clinical examination underwent evaluation with x-rays and a single fat suppressed sequence with MR Imaging applying either T2-w TSE or STIR-TSE at the painful site. False positive and false negative findings were recorded for the conventional x-rays and compared to MRI.

DISCUSSION

Forty four (89.8%) patients were positive for osteonecrotic lesions in this study and 76 symptomatic osteonecrosis lesions were revealed at 14 distinct anatomic sites. The agreement between the x-ray findings and the MR imaging regarding osteonecrosis was 46.9%. Plain x-rays showed 43.4% sensitivity, 100% specificity, 100% positive predictive value and 10.4% negative predictive value. Fast MR imaging with fat suppressed sequences is necessary and adequate as a single method for the investigation of painful skeletal sites in patients with already diagnosed hip osteonecrosis. It allows early diagnosis of the potentially debilitating multiple juxta-articular lesions and consequently their prompt management.

Management of femoral head osteonecrosis: Current concepts

Osteonecrosis of femoral head (ONFH) is a disabling condition of young individuals with ill-defined etiology and pathogenesis. Remains untreated, about 70-80% of the patients progress to secondary hip arthritis. Both operative and nonoperative treatments have been described with variable success rate. Early diagnosis and treatment is the key for success in preserving the hip joint. Once femoral head collapses (>2 mm) or if there is secondary degeneration, hip conservation procedures become ineffective and arthroplasty remains the only better option. We reviewed 157 studies that evaluate different treatment modalities of ONFH and then a final consensus on treatment was made.

Midterm results of treating femoral head osteonecrosis with autogenous corticocancellous bone grafting

BACKGROUND

Appropriate treatment of osteonecrosis of femoral head (ONFH) remains challenging.

OBJECTIVES

Here, we report the results of treating these patients with auto-corticocancellous bone graft from iliac crest to overcome the need for early total hip arthroplasty (THA).

PATIENTS AND METHODS

There were 132 hips (96 patients) with ONFH. Association Research Circulation Osseous (ARCO) type II and III underwent auto-corticocancellous bone grafting from the iliac crest in the current prospective study. Before the operation and in the final postoperative visit, the pain intensity using visual analogue scale (VAS), range of hip motions and Harris hip score (HHS) were determined and compared. Patients were followed for 48.5 ± 17.9 months.

RESULTS

The shape of head and the joint space were preserved in 120 hips (90.9%). There were 12 hips in which the disease progressed to grade IV and resulted in THA in 10 of them. The pain intensity significantly decreased (6.3 ± 4.1 vs. 1.4 ± 2) and HHS (35.8 ± 15.3 vs. 79.5 ± 16.2) and range of motion (ROM) significantly improved after the operation (P < 0.001).

CONCLUSIONS

Necrotic bone removal and filling the femoral head cavity with auto-corticocancellous bone graft from iliac crest is an effective femoral head preserving method in treating patients with precollapse stages of ONFH and preventing the need for early THA, especially in young active populations.

Osteonecrosis of distal tibia in open dislocation fractures of the ankle

INTRODUCTION

Open ankle dislocation fractures are one of the most severe injuries of the ankle. Development of posttraumatic arthrosis is well known. However, there are just a few case reports describing evidence of posttraumatic osteonecrosis (PON) of distal tibia. The pathophysiological mechanism remains unclear and the question of morphologic or personal risk factors cannot be answered. The goal of this study was to evaluate the morphologic characteristics of open dislocated ankle fractures in correlation with the development of PON to facilitate early identification of patients with higher risk of posttraumatic osteonecrosis.

MATERIAL AND METHODS

In this study data from 28 patients with open dislocation fractures of the ankle between 1975 and 2006 found at our databases were evaluated retrospectively. For each patient we documented personal data, mechanism of injury, type of lateral malleolar fracture, severity of open fracture, degree of tibiotalar dislocation, presence of medial malleolar fracture, presence of deltoid ligament rupture, time until joint reduction and kind of surgical treatment. We also documented clinical complications and number of surgeries. Presence of PON was examined by radiographs, magnetic resonance imaging (MRI) or histological analysis.

RESULTS

Within 12 out of 28 patients with open ankle dislocation fractures a PON of the distal tibia could be found. Nine out of 15 patients with high-energy trauma and 12 out of 19 patients with type C fibular fracture developed PON. 73% of male patients and 88% of the patients with type III soft tissue damage according to Gustillo developed PON. However, if patients suffered from type C fibular fracture, total talus dislocation and grade III soft tissue damage ("necrotic triad") PON was developed in 100% of cases. Other patient's characteristics like late joint reduction, postoperative infection or bimalleolar fracture showed no higher proportion of patients with PON.

CONCLUSION

In this study we were able to identify clinical manifestations and risk factors for the development of PON of the distal tibia. All indentified risk factors were associated with heavy fracture mechanisms leading most likely to a serious devascularisation of at least parts of the distal tibial epiphysis. With regard to presented results early identification of patients with higher risk of PON might be possible and maybe additional treatment options can be initialised to protect patients from this process.

Assessment of intraosseous femoral head pressures during cement augmentation of the perforated proximal femur nail antirotation blade

OBJECTIVES

The benefits of cement augmentation with fixation of osteoporotic pertrochanteric fractures have been previously demonstrated. The objective of this study was 3-fold: (1) To quantify the intraosseous pressure produced during cement augmentation of the perforated proximal femoral nail antirotation (PFNA) blades; (2) To assess whether the pressure generated is influenced by the injection rate; and (3) To assess the amount of force applied during the injection.

METHODS

Six pairs of human cadaveric femurs were used in the study. A basicervical osteotomy was performed, and the heads were instrumented with the PFNA blade. Each pair was randomly assigned into 1 of 2 groups: slow versus rapid injection with polymethylmethacrylate (PMMA) cement. In the slow group, the augmentation was performed using 6 consecutive 1 mL injections, each over 10 seconds. In the rapid group, each 1 mL injection was performed over 5 seconds. For intraosseous pressure measurements, transmitters were inserted to a depth of 5 mm at both the superior and inferior apices of the head. The reaction forces on the syringe were measured as well.

RESULTS

There were no significant differences between the slow and rapid injection rates with respect to the peak pressures measured at the 6 time points immediately after cement injection. In both groups, elevations in pressure were transient and returned to baseline values within 30 seconds. The highest pressure recorded in the slow group was 37.3 and 30.7 mm Hg in the rapid group. The force required after each sequential injection increased in both groups; however, significantly higher forces were required to inject cement over 5 than 10 seconds (P = 0.036).

CONCLUSIONS

This in vitro model is the first one to demonstrate that femoral head cement augmentation is associated with a small transient increase in intraosseous pressure with sequential fast and slow 1 mL injections of up to 6 mL PMMA. We conclude that cement augmentation of the perforated PFNA blade carries a low risk of pressure-induced avascular necrosis.

Orthopedic surgery and its complication in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multi-systemic immune-complex mediated autoimmune condition which chiefly affects women during their prime year. While the management of the condition falls into the specialty of internal medicine, patients with SLE often present with signs and symptoms pertaining to the territory of orthopedic surgery such as tendon rupture, carpal tunnel syndrome, osteonecrosis, osteoporotic fracture and infection including septic arthritis, osteomyelitis and spondylodiscitis. While these orthopedic-related conditions are often debilitating in patients with SLE which necessitate management by orthopedic specialists, a high index of suspicion is necessary in diagnosing these conditions early because lupus patients with potentially severe orthopedic conditions such as osteomyelitis frequently present with mild symptoms and subtle signs such as low grade fever, mild hip pain and back tenderness. Additionally, even if these orthopedic conditions can be recognized, complications as a result of surgical procedures are indeed not uncommon. SLE per se and its various associated pharmacological treatments may pose lupus patients to certain surgical risks if they are not properly attended to and managed prior to, during and after surgery. Concerted effort of management and effective communication among orthopedic specialists and rheumatologists play an integral part in enhancing favorable outcome and reduction in postoperative complications for patients with SLE through thorough pre-operative evaluation, careful peri-operative monitoring and treatment, as well as judicious postoperative care.

Osteonecrosis of the hip: treatment options and outcomes

This article reviews the literature regarding the outcomes of various nonoperative and operative treatment options for osteonecrosis of the hip. This article provides the orthopedic community with the latest evidence regarding the suitability of currently available treatment modalities in various stages of the disease.

The therapeutic effect of negative pressure in treating femoral head necrosis in rabbits

Because negative pressure can stimulate vascular proliferation, improve blood circulation and promote osteogenic differentiation of bone marrow stromal cells, we investigated the therapeutic effect of negative pressure on femoral head necrosis (FHN) in a rabbit model. Animals were divided into four groups (n = 60/group): [1] model control, [2] core decompression, [3] negative pressure and [4] normal control groups. Histological investigation revealed that at 4 and 8 weeks postoperatively, improvements were observed in trabecular bone shape, empty lacunae and numbers of bone marrow hematopoietic cells and fat cells in the negative pressure group compared to the core decompression group. At week 8, there were no significant differences between the negative pressure and normal control groups. Immunohistochemistry staining revealed higher expression of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in the femoral heads in the negative pressure group compared with the core decompression group. Transmission electron microscopy revealed that cell organelles were further developed in the negative pressure group compared with the core decompression group. Microvascular ink staining revealed an increased number of bone marrow ink-stained blood vessels, a thicker vascular lumen and increased microvascular density in the negative pressure group relative to the core decompression group. Real-time polymerase chain reaction revealed that expression levels of both VEGF and BMP-2 were higher in the negative pressure group compared with the core decompression group. In summary, negative pressure has a therapeutic effect on FHN. This effect is superior to core decompression, indicating that negative pressure is a potentially valuable method for treating early FHN.

Angiogenesis and bone regeneration by allogeneic mesenchymal stem cell intravenous transplantation in rabbit model of avascular necrotic femoral head

AIM

To explore the feasibility of allogeneic mesenchymal stem cells (MSCs) transplanted intravenously for angiogenesis and bone repair in a rabbit model of avascular necrosis of femoral head (ANFH).

MATERIALS AND METHODS

Forty-five rabbits were randomized into three groups: a blank control group (without treatment), a necrotic control group (ANFH induced but without therapy), and an MSC transplantation group (ANFH induced and treated with MSC transplantation). The biopsies, blood sampling, and imaging examinations were performed on each animal at different time points (2, 4, and 6 wk). To monitor angiogenesis and bone repair progress, examinations included real-time polymerase chain reaction, Western blot analysis, x-ray, computed tomography, Masson trichrome staining, picrosirius red staining, and immunohistochemical staining.

RESULTS

Necrosis and bone collapse were observed in bilateral femoral heads of necrotic rabbits of the necrotic control group, whereas the femoral head morphology was generally restored in the MSC transplantation group. The mRNA levels of Cbfa1, BMP, VEGF, and OPN in bone tissue were significantly higher in the MSC transplantation group than in the necrotic control group. In addition, the total protein amount of Cbfa1 in the MSC transplantation group was also significantly higher than that in the necrotic control group (P < 0.05).

CONCLUSION

Intravenous transplantation of allogeneic MSCs can promote vascular and bone regeneration in the necrotic region of the femoral head in a rabbit model of ANFH. The results of our study suggest that the intravenous transplantation of MSCs could be a potential and minimally invasive treatment option for ANFH patients.