Classification systems for osteonecrosis: an overview

Femoral Neck Fractures With Associated Ipsilateral Femoral Shaft Fractures in Young Adults <50 Years Old: A Multicenter Comparison of 80 Cases Versus Isolated Femoral Neck Fractures

OBJECTIVES

To analyze patients, injury patterns, and treatment of femoral neck fractures (FNFs) in young patients with FNFs associated with shaft fractures (assocFNFs) to improve clinical outcomes. The secondary goal was to compare this injury pattern to that of young patients with isolated FNFs (isolFNFs).

METHODS

DESIGN

Retrospective multicenter cohort series.

SETTING

Twenty-six North American level-1 trauma centers.

PATIENT SELECTION CRITERIA

Skeletally mature patients, <50 years old, treated with operative fixation of an FNF with or without an associated femoral shaft fracture.

OUTCOME MEASURES AND COMPARISONS

The main outcome measurement was treatment failure defined as nonunion, malunion, avascular necrosis, or subsequent major revision surgery. Odds ratios for these modes of treatment were also calculated.

RESULTS

Eighty assocFNFs and 412 isolFNFs evaluated in this study were different in terms of patients, injury patterns, and treatment strategy. Patients with assocFNFs were younger (33.3 ± 8.6 vs. 37.5 ± 8.7 years old, P < 0.001), greater in mean body mass index [BMI] (29.7 vs. 26.6, P < 0.001), and more frequently displaced (95% vs. 73%, P < 0.001), "vertically oriented" Pauwels type 3, P < 0.001 (84% vs. 43%) than for isolFNFs, with all P values < 0.001. AssocFNFs were more commonly repaired with an open reduction (74% vs. 46%, P < 0.001) and fixed-angle implants (59% vs. 39%) (P < 0.001). Importantly, treatment failures were less common for assocFNFs compared with isolFNFs (20% vs. 49%, P < 0.001) with lower rates of failed fixation/nonunion and malunion (P < 0.001 and P = 0.002, respectively). Odds of treatment failure [odds ratio (OR) = 0.270, 95% confidence interval (CI), 0.15-0.48, P < 0.001], nonunion (OR = 0.240, 95% CI, 0.10-0.57, P < 0.001), and malunion (OR = 0.920, 95% CI, 0.01-0.68, P = 0.002) were also lower for assocFNFs. Excellent or good reduction was achieved in 84.2% of assocFNFs reductions and 77.1% in isolFNFs (P = 0.052). AssocFNFs treated with fixed-angle devices performed very well, with only 13.0% failing treatment compared with 51.9% in isolFNFs treated with fixed-angle constructs (P = <0.001) and 33.3% in assocFNFs treated with multiple cannulated screws (P = 0.034). This study also identified the so-called "shelf sign," a transverse ≥6-mm medial-caudal segment of the neck fracture (forming an acute angle with the vertical fracture line) in 54% of assocFNFs and only 9% of isolFNFs (P < 0.001). AssocFNFs with a shelf sign failed in only 5 of 41 (12%) cases.

CONCLUSIONS

AssocFNFs in young patients are characterized by different patient factors, injury patterns, and treatments, than for isolFNFs, and have a relatively better prognosis despite the need for confounding treatment for the associated femoral shaft injury. Treatment failures among assocFNFs repaired with a fixed-angle device occurred at a lower rate compared with isolFNFs treated with any construct type and assocFNFs treated with multiple cannulated screws. The radiographic "shelf sign" was found as a positive prognostic sign in more than half of assocFNFs and predicted a high rate of successful treatment.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Treatment Failure After Repair of Displaced Femoral Neck Fractures in Patients Compared by "Decade of Life": An Analysis of 565 Cases in Adults Less Than 60 years of Age

OBJECTIVES

To study the results of displaced femoral neck fractures (FNFs) in adults less than 60 years of age by comparing patients, injury, treatment, and the characteristics of treatment failure specifically according to patients' age at injury, that is, by their "decade of life" [ie, "under 30" (29 years and younger), "the 30s" (30-39 years), "the 40s" (40-49 years), and "the 50s" (50-59 years)].

METHODS

DESIGN

Multicenter retrospective comparative cohort series.

SETTING

Twenty-six North American Level 1 Trauma Centers.

PATIENT SELECTION CRITERIA

Skeletally mature patients aged 18-59 years with operative repair of displaced FNFs.

OUTCOME MEASURES AND COMPARISONS

Main outcome measures were treatment failures (fixation failure and/or nonunion, osteonecrosis, malunion, and the need for subsequent major reconstructive surgery (arthroplasty or proximal femoral osteotomy). These were compared across decades of adult life through middle age (<30 years, 30-39 years, 40-49 years, and 50-59 years).

RESULTS

Overall, treatment failure was observed in 264 of 565 (47%) of all hips. The mean age was 42.2 years, 35.8% of patients were women, and the mean Pauwels angle was 53.8 degrees. Complications and the need for major secondary surgeries increased with each increasing decade of life assessed: 36% of failure occurred in patients <30 years of age, 40% in their 30s, 48% in their 40s, and 57% in their 50s (P < 0.001). Rates of osteonecrosis increased with decades of life (under 30s and 30s vs. 40s vs. 50s developed osteonecrosis in 10%, 10%, 20%, and 27% of hips, P < 0.001), while fixation failure and/or nonunion only increased by decade of life to a level of trend (P = 0.06). Reparative methods varied widely between decade-long age groups, including reduction type (open vs. closed, P < 0.001), reduction quality (P = 0.030), and construct type (cannulated screws vs. fixed angle devices, P = 0.024), while some variables evaluated did not change with age group.

CONCLUSIONS

Displaced FNFs in young and middle-aged adults are a challenging clinical problem with a high rate of treatment failure. Major complications and the need for complex reconstructive surgery increased greatly by decade of life with the patients in their sixth decade experiencing osteonecrosis at the highest rate seen among patients in the decades studied. Interestingly, treatments provided to patients in their 50s were notably different than those provided to younger patient groups.

LEVEL OF EVIDENCE

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

Clinical efficacy of Femoral Neck System for treatment of unstable femoral neck fractures in young adults

OBJECTIVE

This study was performed to evaluate the mid-term clinical efficacy of the Femoral Neck System (FNS) (DePuy Synthes, Zuchwil, Switzerland) in treating young patients with unstable Pauwels type III femoral neck fractures.

METHODS

We performed a retrospective observational analysis of 21 young adults treated with the FNS. Clinical outcomes were assessed based on fracture reduction quality, Harris hip scores, and postoperative complication rates.

RESULTS

The study comprised 21 patients with a mean age of 35 years (range, 20-50 years) who were followed for a mean duration of 22.8 months (range, 16-30 months). Closed reduction was unfeasible in three (14.3%) patients, each of whom required open reduction. Notable postoperative complications were avascular necrosis in two (9.5%) patients, nonunion in one (4.7%), and implant failure in one (4.7%). Each of these complications led to the requirement for total hip arthroplasty.

CONCLUSION

The favorable mid-term clinical outcomes of this study indicate that the FNS is a potentially effective treatment modality for young individuals with unstable Pauwels type III femoral neck fractures.

Development of a risk-predicting score for hip preservation with bone grafting therapy for osteonecrosis

Identification and differentiation of appropriate indications on hip preserving with bone grafting therapy remains a crucial challenge in the treatment of osteonecrosis of the femoral head (ONFH). A prospective cohort study on bone grafting therapy for ONFH aimed to evaluate hip survival rates, and to establish a risk scoring derived from potential risk factors (multivariable model) for hip preservation. Eight variables were identified to be strongly correlated with a decreased rate of hip survival post-therapy, and a comprehensive risk scoring was developed for predicting hip-preservation outcomes. The C-index stood at 0.72, and the areas under the receiver operating characteristics for the risk score's 5- and 10-year hip failure event predictions were 0.74 and 0.72, respectively. This risk score outperforms conventional methods in forecasting hip preservation. Bone grafting shows sustained benefits in treating ONFH when applied under the right indications. Furthermore, the risk scoring proves valuable as a decision-making tool, facilitating risk stratification for ONFH treatments in future.

Icariin-loaded 3D-printed porous Ti6Al4V reconstruction rods for the treatment of necrotic femoral heads

Avascular necrosis of the femoral head is a prevalent hip joint disease. Due to the damage and destruction of the blood supply of the femoral head, the ischemic necrosis of bone cells and bone marrow leads to the structural changes and the collapse of the femoral head. In this study, an icariin-loaded 3D-printed porous Ti6Al4V reconstruction rod (referred to as reconstruction rod) was prepared by 3D printing technology. The mechanical validity of the reconstruction rod was verified by finite element analysis. Through infilling of mercapto hyaluronic acid hydrogel containing icariin into the porous structure, the loading of icariin was achieved. The biological efficacy of the reconstruction rod was confirmed through in vitro cell experiments, which demonstrated its ability to enhance MC3T3-E1 cell proliferation and facilitate cellular adhesion and spreading. The therapeutic efficacy of the reconstruction rod was validated in vivo through a femoral head necrosis model using animal experiments. The results demonstrated that the reconstruction rod facilitated osteogenesis and neovascularization, leading to effective osseointegration between bone and implant. This study provides innovative strategy for the treatment of early avascular necrosis of the femoral head. STATEMENT OF SIGNIFICANCE: The bioactivity of medical titanium alloy implants plays an important role in bone tissue engineering. This study proposed a medicine and device integrated designed porous Ti6Al4V reconstruction rod for avascular necrosis of the femoral head, whose macroscopic structure was customized by selective laser melting. The bionic porous structure of the reconstruction rod promoted the growth of bone tissue and formed an effective interface integration. Meanwhile, the loaded icariin promoted new bone and vascular regeneration, and increased the bone mass and bone density. Therefore, the implantation of reconstruction rod interfered with the further development of necrosis and provided a positive therapeutic effect. This study provides innovative strategies for the treatment of early avascular necrosis of femoral head.

Functional Outcomes for Children, Adolescents, and Young Adults with Osteonecrosis following Hip Core Decompression

Background

Patients with pediatric leukemia and sickle cell disease are at risk for developing osteonecrosis (ON), a disease that can result in pain, loss of function, and disability. Hip core decompression surgery is an option aimed to prevent femoral head collapse and avoid future arthroplasty.

Objective

Describe functional outcomes and gait quality among a young population with hip ON before and after hip core decompression.

Methods

Study included participants with hip ON secondary to treatment for hematologic malignancy or sickle cell disease, between 8 and 29 years old, requiring hip core decompression surgery. At one-year follow-up, 13 participants (9 male, median age 17 years) completed the Functional Mobility Assessment (FMA), range of motion, and GAITRite® testing.

Results

Participants demonstrated improved mobility and endurance on the FMA at 1-year post-operatively compared to pre-operatively, with higher scores for time on the Timed Up and Go (mean FMA score = 2.92 [SD = 1.32] vs. 2.07 [SD = 1.70]), time on the Timed Up and Down Stairs (3.69 [0.85] vs. 2.92 [1.66]), and 9-Minute Walk Test scores for distance walked (2.69 [0.63] vs. 2.23 [0.93]) and heart rate (4.54 [0.66] vs. 3.31 [1.38]). GAITRite® analysis also showed improvements in many gait parameters at one-year follow-up.

Limitations

Cancer treatment complications other than ON could have contributed to results, not all eligible participants agreed to participate, and follow-up was only one year.

Conclusions

Young patients with hip ON demonstrated improvements in functional mobility, endurance, and gait quality one year following hip core decompression.

Osteonecrose da cabeça femoral: Artigo de atualização

Among the pathologies that affect the hip joint, osteonecrosis of the femoral head (ONFH) is probably the most intriguing and challenging. It consists of a multifactorial disease with a highly-variable spectrum in its clinical presentation. It has a devastating effect, due to disabling painful conditions, both for usual activities and sports. Given the huge range of risk factors, such as prolonged use of corticosteroids (especially in cases of rheumatologic diseases), trauma sequelae, sickle cell anemia, HIV, alcoholism, smoking, blood dyscrasias, and several other diseases that compromise the blood supply to the femoral head, ONFH has a varied clinical presentation and prognosis, which makes it difficult to determine a specific treatment, especially in cases in which chondral involvement has not yet occurred and the hip joint is still preserved. These are the main factors found in the literature that determine the classifications of this pathology. The range of treatments includes several options for cases in which an attempt is made to save the joint: conservative treatment, traditional decompression and/or combined with some type of adjuvant treatment (homologous grafting, synthetic grafting, vascularized grafts, tantalum screws, and bone marrow aspirate injection), and, for cases in which there is already a subchondral fracture and/or collapse of the femoral head and/or a reduction in the joint space, femoral osteotomies or total hip arthroplasty are commonly performed.

What is the Level of Evidence Substantiating Commercial Payers' Coverage Policies for Total Joint Arthroplasty?

BACKGROUND

The prevalence of total joint arthroplasty (TJA) in the United States has drawn the attention of health care stakeholders. The payers have also used a variety of strategies to regulate the medical necessity of these procedures. The purpose of this study was to examine the level of evidence of the coverage policies being used by commercial payers in the United States.

METHODS

The references of the coverage policies of four commercial insurance companies were reviewed for type of document, level of evidence, applicability to a TJA population, and success of nonoperative treatment in patients with severe degenerative joint disease.

RESULTS

282 documents were reviewed. 45.8% were primary journal articles, 14.2% were level I or II, 41.2% were applicable to patients who were candidates for TJA, and 9.9% discussed the success of nonoperative treatment in patients who would be candidates for TJA.

CONCLUSION

Most of the references cited by commercial payers are of a lower level of scientific evidence and not applicable to patients considered to be candidates for TJA. This is relatively uniform across the reviewed payers. The dearth of high-quality literature cited by commercial payers reflects the lack of evidence and difficulty in conducting high level studies on the outcomes of nonoperative versus operative treatment for patients with severe, symptomatic osteoarthritis. Patients, surgeons, and payers would all benefit from such studies and we encourage professional societies to strive toward that end through multicenter collaboration.

Analysis of Bone Microarchitectural Changes and Structural Damage in Sickle Cell Disease-Induced Avascular Necrosis Using Raman Spectroscopy: Is there potential for medical management?

Objectives

Bone failure due to avascular necrosis (AVN) is a complex pathological phenomenon. Analysis of molecular changes in the bone matrix may help to shed light on the disease process and guide management. This study aimed to explore changes in bone quality and structural damage caused by sickle cell disease (SCD)-induced AVN using Raman spectroscopy.

Methods

A total of 10 necrotic femoral heads were obtained from seven SCD patients who underwent total hip replacements. The femoral heads were cut in half and scanned using Raman spectroscopy in correlation with preoperative magnetic resonance imaging to identify necrotic and healthy control areas. Subsequently, samples were examined to determine changes in bone mineralisation, crystallinity, carbonate content, collagen cross-linking and mineral and collagen fibril orientation.

Results

Significant changes were observed in bone mineral content, mineral-to-organic content and collagen fibril orientation in necrotic compared to control areas (P ≤0.050).

Conclusion

The necrotic samples displayed severe structural damage and loss of mineral and organic contents. Similar Raman signals have been reported in other metabolic bone diseases such as osteoporosis, thereby potentially supporting the use of medical treatment in AVN to promote bone quality.

Necrosis of the femoral head, X-ray microtomography (microCT) and histology of retrieved human femoral heads

Aseptic osteonecrosis of the hip (AON) is a rare, but well-known pathology in rheumatology and orthopedic surgery that is a necrosis of the articular cartilage secondary to a necrosis of the subchondral bone. The microscopic aspect is well known, but the microCT aspect has never been reported or correlated with histopathological findings. The objective of this study was to improve the knowledge of the pathophysiology of AON using histochemistry and microCT. One hundred and sixty femoral heads with stage 3 or 4 AON were analyzed: one half of the head was sent for microCT analysis after impregnation with phosphotungstic acid (PTA) and the other half was used for histological analysis without decalcification. The microCT analysis provides relevant information on the cracked articular cartilage and the relationship with the necrotic subchondral trabecular bone well illustrated on three videos. In histology, Goldner's trichrome showed that the articular cartilage remains well preserved for a long time. In addition, toluidine blue staining reveals a modeling process, i.e. the apposition of new bone without prior resorption by osteoclasts. Rhodamine B staining (fluorescence analysis) reveals that the osteonecrotic trabeculae and subchondral bone were devoid of osteocytes. Areas of peri-necrotic osteosclerosis are due to direct bone formation on the surface of pre-existing necrotic trabeculae.

Evidence-Supported HBO Therapy in Femoral Head Necrosis: A Systematic Review and Meta-Analysis

Although many studies have shown that hyperbaric oxygen (HBO) therapy can significantly improve symptoms and quality of life of patients affected by femoral head necrosis, this therapy is not worldwide approved yet. This meta-analysis was performed to evaluate its clinical effect. Relevant studies published before May 2020 were systematically searched using terms related to HBO and femoral head necrosis. Fixed and random-effects models were used to estimate the odds ratio (OR) with 95% confidence intervals (CI). Subgroup analyses and publication bias tests were carried out to explore potential study heterogeneity and bias. Ten studies involving 353 controls and 368 HBO-treated cases were included, most of which were conducted on Asian population. The clinical effect in the HBO therapy group was 3.84 times higher than in the control group (OR = 3.84, 95% CI (2.10, 7.02), p < 0.00001). Subgroup analyses showed that the clinical effect of HBO therapy was statistically significant in the Asian subpopulation which represented most of the subjects (OR = 3.53, 95% CI (1.87, 6.64), p < 0.00001), but not in the non-Asian subpopulation, probably because of insufficient numerosity (OR = 7.41, 95% CI (0.73, 75.71), p = 0.09). The results of this meta-analysis suggest that patients with femoral head necrosis treated with HBO therapy can achieve a significant clinical improvement.

Microstructural and mechanical evaluations of region segmentation methods in classifications of osteonecrosis

Measuring the location of necrotic lesions is necessary to diagnosis of osteonecrosis. Different region segmentation methods of the femoral head were proposed to quantitatively measure necrotic lesions including Japanese Investigation Committee for Avascular Necrosis (JIC) classification and China-Japan Friendship Hospital (CJFH) classification. Biomechanical methods could bring important information to evaluate the reasonability of these classifications. In this study, microstructural and mechanical properties of trabecular bone were quantitatively analyzed according to the region segmentation methods described in these classifications. Microstructural parameters of trabecular bone were analyzed based on micro-CT scanning. Mechanical properties were measured through Nanoindentation and micro-finite element analysis. It was found that microstructural and mechanical properties of trabecular bone in the middle region was more adaptive to load bearing than the medial and lateral regions according to the CJFH classification; lesions in the middle region could bring more changes to microstructure and stress distribution. According to JIC classification, differences of microstructural and mechanical properties among the three regions were not significant. Biomechanical characteristics of trabecular bones could be better distinguished with CJFH classification.

Culture-Expanded Autologous Adipose-Derived Mesenchymal Stem Cell Treatment for Osteonecrosis of the Femoral Head

Backgroud

Outcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.

Methods

Eighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.

Results

Preoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).

Conclusions

Our outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.

Bone marrow lesion on magnetic resonance imaging indicates the last chance for hip osteonecrosis treated with vascularized fibular grafting before collapse

PURPOSE

Timing of surgery is the most critical prognostic factor for hip osteonecrosis treated with free vascularized fibular grafting (FVFG). Bone marrow lesion (BML) on MRI usually occurs immediately before femoral head collapse. We conducted a retrospective cohort study to evaluate whether the noncollapsed hips with BML can benefit from FVFG.

METHODS

Consecutive patients undergoing modified FVFG were identified from our clinical repository between January 2014 and December 2014. Based on whether BML was pre-operatively detected, the four year radiographic and clinical outcomes were compared.

RESULTS

In the BML cohort, 22 of 53 hips (42%) showed radiographic signs of osteonecrosis progression, which was significantly higher than that in the control cohort (8 of 49, 16%; P = 0.005). The BML hips showed a significantly lower pre-operative Harris Hip Score (HHS) than those without BML (77.8 vs. 85.5, P = 0.046), whereas no such difference was observed in the final HHS or its post-operative improvement (HHS 90 vs. 94, P = 0.397; HHS improvement 12 vs. 8, P = 0.067). In the subgroup of patients with a pre-operative HHS lower than 80, BML hips were associated with a slightly lower final HHS than hips without BML. Four of 5 (80%) failed hips with BML had a poor pre-operative hip function.

CONCLUSION

BML indicates the last chance for a reproducible improvement in the treatment of hip osteonecrosis with FVFG before collapse. However, the concomitant lower pre-operative HHS (< 80) is a poor prognostic factor for BML-positive hips.

The pathogenesis, diagnosis and clinical manifestations of steroid-induced osteonecrosis

Corticosteroid associated osteonecrosis is bone death resulting from the use of chronic glucocorticoids and most commonly affects the femoral head, although the bones such as around knee joint, wrist joint and ankle joint can be affected. The pathogenesis is likely multifactorial, with genetic and environmental factors playing a role. Epigenetics may be the mechanism by which environment exerts it effects. In spite of recent discoveries, the exact pathogenesis of corticosteroid associated osteonecrosis is unknown. Over the past few years, more miRNA's have been found to be associated with osteonecrosis. The older mechanisms such as a coagulopathy, abnormalities in apoptosis and lipid metabolism dysfunction are still believed to play a role. The role of inflammatory pathways including the PDK1/AKT/mTOR signaling pathway, the PERK and Parkin pathways have been increasingly recognized as playing a mechanistic role. Histological damage to the joint can occur before the presence of symptoms. The most common symptoms are pain and an inability to bear weight. Differential diagnosis includes infection, bone marrow edema syndrome or subchondral fracture. Early detection is important for successful management of the condition. MRI is the best radiologic technique to diagnosis femoral head osteonecrosis. Multiple staging systems for osteonecrosis have been used over the years, including the Ficat and Arlet system and the Steinberg criteria. The later stages of these staging systems are irreversible. Both non-surgical (conservative) and surgical modes of therapy are used in the treatment of osteonecrosis.

Long-Term Functional Outcomes Among Childhood Survivors of Cancer Who Have a History of Osteonecrosis

BACKGROUND

Glucocorticoids used to treat childhood leukemia and lymphoma can result in osteonecrosis, leading to physical dysfunction and pain. Improving survival rates warrants research into long-term outcomes among this population.

OBJECTIVE

The objective of this study was to compare the physical function and quality of life (QOL) of survivors of childhood cancer who had an osteonecrosis history with that of survivors who had no osteonecrosis history and with that of people who were healthy (controls).

DESIGN

This was a cross-sectional study.

METHODS

This study included St Jude Lifetime Cohort Study participants who were ≥ 10 years from the diagnosis of childhood leukemia or lymphoma and ≥ 18 years old; 135 had osteonecrosis (52.5% men; mean age = 27.7 [SD = 6.08] years) and 1560 had no osteonecrosis history (52.4% men; mean age = 33.3 [SD = 8.54] years). This study also included 272 people who were from the community and who were healthy (community controls) (47.7% men; mean age = 35.1 [SD = 10.46] years). The participants completed functional assessments and questionnaires about QOL.

RESULTS

Survivors with osteonecrosis scored lower than other survivors and controls for dorsiflexion strength (mean score = 16.50 [SD = 7.91] vs 24.17 [SD = 8.61] N·m/kg) and scored lower than controls for flexibility with the sit-and-reach test (20.61 [SD = 9.70] vs 23.96 [SD = 10.73] cm), function on the Physical Performance Test (mean score = 22.73 [SD = 2.05] vs 23.58 [SD = 0.88]), and mobility on the Timed "Up & Go" Test (5.66 [SD = 2.25] vs 5.12 [SD = 1.28] seconds). Survivors with hip osteonecrosis requiring surgery scored lower than survivors without osteonecrosis for dorsiflexion strength (13.75 [SD = 8.82] vs 18.48 [SD = 9.04] N·m/kg), flexibility (15.79 [SD = 8.93] vs 20.37 [SD = 10.14] cm), and endurance on the 6-minute walk test (523.50 [SD = 103.00] vs 572.10 [SD = 102.40] m).

LIMITATIONS

Because some eligible survivors declined to participate, possible selection bias was a limitation of this study.

CONCLUSIONS

Survivors of childhood leukemia and lymphoma with and without osteonecrosis demonstrated impaired physical performance and reported reduced QOL compared with controls, with those requiring surgery for osteonecrosis most at risk for impairments. It may be beneficial to provide strengthening, flexibility, and endurance interventions for patients who have pediatric cancer and osteonecrosis for long-term function.

Osteonecrosis of the Femoral Head

Osteonecrosis of the femoral head most commonly arises from trauma or corticosteroid and alcohol use but is also associated with blood dyscrasias and metabolic and coagulation disorders. Initial evaluation includes a history and physical examination and plain radiographs. Early-stage osteonecrosis is best evaluated by MRI. The Ficat and Arlet classification system is the most widely used. Nonoperative treatment has been studied using bisphosphonates, anticoagulants, vasodilators, statins, and biophysical modalities. Operative treatment includes core decompression with or without adjuvants, such as autologous bone marrow, whereas total hip arthroplasty is reserved for advanced-stage osteonecrosis in older patients or those who have failed joint-preserving treatment.

Natural History of Avascular Necrosis in the Talus: When to Operate

Avascular necrosis (AVN) of the talus bone is a progressive and debilitating consequence of trauma or exposure to a variety of risk factors. The Ficat classification describes current understanding of the natural history of AVN, including preclinical, preradiographic, precollapse, postcollapse, and arthritic stages. The size and location of the avascular region likely determines risk of progression; however, symptoms do not correlate with stage. Patients may be minimally symptomatic despite diffuse involvement for long periods. Joint-sparing strategies have shown promise but do not universally prevent progression of the disease. When bone structure fails, joint-sacrificing strategies may be required.

Prevalence of CAM deformity and its influence on therapy success in patients with osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) and CAM-type femoroacetabular impingement (FAI) present two different pathologies of the hip joint. The aim of this study is to describe the prevalence of CAM-FAI in a collective of ONFH hips and to evaluate its influence on ONFH therapy outcome. A cohort of 86 ONFH hips with a mean follow-up of 46.7 months (±20.5) after advanced core decompression (ACD) was evaluated regarding CAM deformity by measuring the alpha angle (α) and head-neck offset. The influence of CAM-type FAI was investigated using the Kaplan-Meier estimator and the Cox regression model. The mean α was 60.4° (±13.8) with 41 hips (47.7%) being ≥60°. The mean head-neck offset was 4.5 mm (±3.2), with 78 hips (90.7%) being ≤9 mm. Survival analysis indicated noticeably better ACD results for α < 60° versus α ≥ 60° (p = 0.07). Treatment failure within the first 2 years was statistically estimated as 27.7% for α < 60° versus 40.7% for α ≥ 60°: The hazard ratio for α ≥ 60° was 1.94. Head-neck offset-dependent survival showed better, though not significant, results for offset >9 mm (p = 0.38, hazard ratio 1.89 for offsets ≤9 mm). The prevalence of CAM-type deformity is greatly increased in patients with concomitant ONFH. There is a strong indication that CAM-type FAI has a negative influence on ONFH therapy outcome. The risk that ONFH treatment will fail seems to be twice as high for α ≥ 60° as for α < 60°. We recommend cotreatment of pathological head-neck offset in patients with ONFH.

Osteonecrosis of the Femoral Head: Etiology, Investigations, and Management

Femoral head osteonecrosis is a condition caused by a compromise of the blood supply of the femoral head. The precarious blood supply of the head and its role as a major weight-bearing joint makes it one of the most common bones to be affected by osteonecrosis. We describe the etiology, clinical presentation, investigations and common management options used nowadays to treat it.

Classification systems of hip osteonecrosis: an updated review

PURPOSE

Osteonecrosis of the femoral head (ONFH) typically impacts middle-aged patients who are typically more active and in whom many surgeons would try to delay performing a total hip arthroplasty (THA). This poses a clinical decision-making challenge. Therefore, several options for joint preservation have been advocated, but varying indications and success rates have led to debate on when to use the various procedures. This is due in part to the lack of a generalized system for assessing ONFH, as well as the absence of a standardized method of data collection for patient stratification. Due to the paucity of studies, in this review, we aimed to provide an up-to-date review of the most widely utilized classification systems and discuss the characteristics of each system.

METHODS

A comprehensive literature review was conducted. Studies published between January 1st, 1975 and March 1st, 2018 were reviewed. The following key words were used in combination with Boolean operators AND or OR for the literature search: "osteonecrosis," "avascular necrosis," "hip," "femoral head," "classification," "reliability," and "validity." We defined the inclusion criteria for qualifying studies for this review as follows: (1) studies that reported on the classification systems for hip osteonecrosis, (2) studies that reported on the inter-observer reliability of the classification systems, and (3) studies that reported on the intra-observer reliability of any ONFH classification systems. In addition, we employed the following exclusion criteria: (1) studies that assessed classification systems for traumatic osteonecrosis, (2) Legg-Calvé-Perthes disease, or (3) Developmental Dysplasia of the Hip. Additionally, we excluded case reports and duplicate studies among searched databases.

RESULTS

The following classification systems were the most commonly utilized: The Ficat and Arlet, Steinberg, the Association Research Circulation Osseous (ARCO), and the Japanese Investigation Committee (JIC) classification systems. The details of each system have been discussed and their inter- and intra-observer reliability has been compared.

CONCLUSION

To this date, there is a lack of consensus on a universal and comprehensive system, and the use of any of the previous classification systems is a matter of dealer's choice. The Ficat and Arlet system was the earliest yet remains the most widely utilized system. Newer classification systems have been developed and some such as the JIC shows promising prognostic value while maintaining simplicity. However, larger validating studies are needed. While all of these systems have their strengths, the lack of a unified classification and staging system is still a problem in the diagnosis and prognosis ONFH. Further multi-center collaborative efforts among osteonecrosis experts are needed to adopt a universal classification system that may positively reflect on patient's outcomes.

What is the rate of patients undergoing a total hip arthroplasty after core decompression and insertion of a tantalum rod in osteonecrosis of the femoral head: a systematic review

PURPOSE

Core decompression (CD) may be effective when performed during the early stages of osteonecrosis of the femoral head (ONFH). Tantalum may be added as a rod that would allow putting some mechanical constraints on the femoral head. We aimed to estimate the rate of total hip arthroplasty after CD and insertion of a tantalum rod during early stages of OFNH.

METHODS

We searched systematically Medline via PubMed and the Cochrane Library. Our primary endpoint was the rate of patients undergoing a total hip arthroplasty after CD and insertion of a tantalum rod. Secondary endpoints were the delay between the initial surgery and the arthroplasty, the functional improvement, and the rate of complications.

RESULTS

We included seven  studies reporting the results of 232 patients (297 hips) that were operated on by CD and insertion of a tantalum rod. At a mean follow-up of 26.97 months, 24.63% of the included hips underwent a hip arthroplasty (6-56%, SD = 17.34%). The mean delay between the initial surgery and the arthroplasty was 14.94 months (10.20-22.90; SD = 5.25), the mean improvement of Harris Hip Score was 27.66 (20.20-36.90; SD = 6.48), and the mean rate of femoral fracture was 2.43% (0-13%, SD = 4.89%).

CONCLUSION

CD and insertion of a tantalum rod may represent a solution in order to improve the mechanical support and to give a rate of conversion in arthroplasty that is acceptable.

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.

Hip osteonecroses treated with calcium sulfate-calcium phosphate bone graft substitute have different results according to the cause of osteonecrosis: alcohol abuse or corticosteroid-induced

INTRODUCTION

The aim of the study was to assess the factors influencing the final results of treatment of the femoral head osteonecrosis (ONFH) with core decompression and bone substitute grafting. The special interest was focused on comparison between alcohol- and steroid-induced ONFHs.

MATERIAL AND METHODS

In this prospective study, a total of 53 patients (58 hips) in the mean age of 35.5 years were included: 29 had a history of alcohol use (32 hips) and 24 of steroid use (26 hips). The mean follow-up was 4.2 years (minimum 3 years).

RESULTS

At last follow-up, significant improvements were noted in the Harris Hip Score (HHS) (mean 44.0 vs 55.9 points, p < 0.00002) and VAS scores (mean 7.0 vs 5.8 points, p < 0.0002) for the whole ONFH cohort, comparing to pre-operative status. The degree of improvement did not differ between Ficat and Arlet grade II and grade III (mean 14.9 vs 6.2 points, respectively, p = 0.1). No change was found between the final and initial results in this group in the steroid group (HHS mean 42.2 vs 45.5 points, p = 0.5 and VAS mean 6.8 vs 6.5 points, p = 0.5), but the improvement was noted in the alcohol group (HHS mean 45.5 vs 64.4 points, p < 0.0001; VAS mean 7.1 vs 5.2 points, p < 0.0001) comparing to pre-operative status.

CONCLUSIONS

Presented treatment of ONFH significantly improves hip function, offers pain reduction, and gives similar functional improvement for hips scoring grade II and III on the Ficat and Arlet scale. A good response to operative treatment is seen in patients with alcohol-induced ONFH, but not in those with steroid-induced ONFH.

The kinetics of remodeling of a calcium sulfate/calcium phosphate bioceramic

In the last years considerable research and development activity have been expended to find new ceramic bone substitutes for the treatment of bone defects. However in many cases the drawback of synthethic bone substitutes are the slow graft incorporation and remodelling into the host bone. The purpose of this study was to analyze the kinetics of resorption and new bone formation of new calcium sulfate (CaSO₄)/calcium phosphate (CaPO₄) bioceramic engineered to enhance its bone forming properties. We prospectively evaluated the results of a series of 15 hips with osteonecrosis of the femoral head (ONFH) treated at with core decompression and injection of the CaSO₄/CaPO₄ composite. In all hips, a quantitative computed tomography (QTC) scan was taken within one week after the surgery, at 12 months, 2 years and finally with a minimum of 4 years follow-up. The mean HU in the immediate post-operative period was 1445 (Range 1388-1602); At one year the mean HU strongly decrease at 556.6 HU (P < 0.01); The mean HU at 2 years follow-up further decreased to 475.1. The mean HU at 4 years was unchanged. The quantitative and qualitative CT scan data of this series indicates that the CaSO₄-CaPO₄ ceramic composite resorbs over a narrow timeframe and the gradual resorption of the graft within the defect provides an ideal environment for the direct new bone growth that propagates across the defect.

Knowledge insufficient: the management of haemoglobin SC disease

Although haemoglobin SC (HbSC) accounts for 30% of sickle cell disease (SCD) in the United States and United Kingdom, evidence-based guidelines for genotype specific management are lacking. The unique pathology of HbSC disease is complex, characterized by erythrocyte dehydration, intracellular sickling and increased blood viscosity. The evaluation and treatment of patients with HbSC is largely inferred from studies of SCD consisting mostly of haemoglobin SS (HbSS) patients. These studies are underpowered to allow definitive conclusions about HbSC. We review the pathophysiology of HbSC disease, including known and potential differences between HbSS and HbSC, and highlight knowledge gaps in HbSC disease management. Clinical and translational research is needed to develop targeted treatments and to validate management recommendations for efficacy, safety and impact on quality of life for people with HbSC.

Combined with Bone Marrow-Derived Cells and rhBMP-2 for Osteonecrosis after Femoral Neck Fractures in Children and Adolescents: A case series

Osteonecrosis of the femoral head (ONFH) following femoral neck fractures is a rare, yet severe, disorder in children and adolescents. This study evaluated the effectiveness of core decompression (CD) combined with implantation of bone marrow-derived cells (BMDC) and rhBMP-2 for osteonecrosis of femoral head (ONFH) after femoral neck fractures in children and adolescents. This study included 51 patients, aged 11.4-18.1 years, with ARCO stages I-III ONFH after femoral neck fractures between 2004 and 2010. The hips were divided into two groups based on whether the lateral pillar of the femoral head (LPFH) was preserved: LPFH and non-LPFH groups. All patients were followed up clinically and radiographically for a minimum of 5 years. 44 patients (86.3%) had improved clinical outcome. Radiologically, 9 of the 51 hips (17.6%) exhibited collapse onset or progression of the femoral head or narrowing of the hip joint space, and one patient in the non-LPFH group required hip arthroplasty due to the worsened syndrome. The technique provided an effective therapeutic option for children and adolescents with ONFH following femoral neck fractures. It relieves hip pain and prevents the progression of osteonecrosis in young patients lasting more than 5 years after surgery.

Osteonecrosis of the femoral head, nonunion and potential risk factors in Pauwels grade-3 femoral neck fractures: A retrospective cohort study

The present study was to analyze clinical outcome of Pauwels grade-3 femoral neck fractures treated by different surgical techniques. Potential risk factors associated with nonunion and osteonecrosis of the femoral head (ONFH) were investigated as well. The retrospective study comprised of 67 sequential patients treated between January 2008 and December 2011. Patients with Pauwels grade-3 femoral neck fractures were treated by operative reduction and internal fixation. Cannulated screws (CS) were used in 46 patients, dynamic hip screw plus CS (DHS+CS) in 14, and locking compression plate (LCP) for proximal femur in 7. Reduction quality was assessed according to Haidukewych criteria. Postoperative radiographic examinations were conducted to observe fracture healing. Fracture displacement, comminution, fashion of internal fixation, and the sliding effect were analyzed, regarding the incidence of nonunion and ONFH. All patients had a follow-up of 21.6 ± 6.0 months on average. The phenomenon of sliding effect was observed in 16 cases (23.9%). In terms of reduction quality, 64 cases were graded as excellent, 2 were good, and 1 was poor. ONFH was presented in 15 cases (22.4%) and nonunion was found in 8 (11.9%), with 1 patient had ONFH and nonunion concomitantly. Profound hip contour was preserved in 45 cases (67.2%). The fashion of internal fixation yielded different results regarding ONFH and nonunion, whereas the effects of fracture displacement, comminution, and the sliding effect were not significant. ONFH and nonunion were common complications following Pauwels grade-3 femoral neck fractures. Higher incidence of ONFH in DHS+CS and of nonunion in the LCP group should be noted.

Core Decompression and Autologous Bone Marrow Concentrate for Treatment of Femoral Head Osteonecrosis: A Randomized Prospective Study

The aim of this study was to investigate the safety of injection of bone marrow aspirate concentrate during core decompression and to study its clinical (visual analogue scale; Harris-Hip-score) and radiological outcomes (magnetic resonance imaging). In this prospective and randomized clinical trial we evaluated 24 consecutive patients with non-traumatic femoral head necrosis (FHN) during a period of two years after intervention. In vitro analysis of mesenchymal stem cells was performed by evaluating the fibroblast colony forming units (CFU-Fs). Postoperatively, significant decrease in pain associated with a functional benefit lasting was observed. However, there was no difference in the clinical outcome between the two study groups. Over the period of two years there was no significant difference between the head survival rate between both groups. In contrast to that, we could not perceive any significant change in the volume of FHN in both treatment groups related to the longitudinal course after treating. The number of CFU showed a significant increase after centrifugation. This trial could not detect a benefit from the additional injection of bone marrow concentrate with regard to bone regeneration and clinical outcome in the short term.

Incidence and outcome of osteonecrosis in children and adolescents after intensive therapy for acute lymphoblastic leukemia (ALL)

Osteonecrosis (ON), a significant complication following treatment of acute lymphoblastic leukemia (ALL), has a profound impact on quality of life of ALL survivors. We studied incidence and outcome of ON in patients treated on or according to Australian and New Zealand Children's Haematology/ Oncology Group (ANZCHOG) study 8 at The Children's Hospital at Westmead. The study involved retrospective chart review of the patients. ON was defined by development of symptoms and confirmed by magnetic resonance imaging. From 2002-2011, 251 patients (143M, 108F, 59 Standard Risk (SR), 159 Medium Risk (MR) 5 High Risk (HR), and 28 Very high risk (VHR)) were treated according to study 8. Eighteen (7M, 11F, 2 SR, 12 MR, 4 VHR) patients developed ON (7.2%). Median age at diagnosis was 13.05 years(4.3-16.7). Incidence of ON in patients > 10 years at diagnosis was 29%. Six out of 18 patients developed ON after allogeneic stem cell transplantation. Median time from diagnosis to the development of ON following chemotherapy for ALL was 1.15 years (range 0.25-2.12). Most patients were treated with intravenous Zoledronic acid. At last follow-up, three patients had undergone arthroplasty, two patients were symptom free, and the remaining 13 patients reported persistent pain with activity. A majority of patients with ON of the hips had radiological progression. Overall, 7% of patients with ALL developed ON. Age >10 years was the most important risk factor. At last follow-up, 70% of patients had persistent symptoms. Although Zoledronic acid improved pain, most patients with ON of the hips had radiological progression.

Prevalence of clinical anxiety, clinical depression and associated risk factors in chinese young and middle-aged patients with osteonecrosis of the femoral head

Objective

To investigate the prevalence of clinical anxiety and clinical depression in Chinese young and mid-aged patients with osteonecrosis of the femoral head (ONFH) and to analyze their potential risk factors.

Methods

Two hundred and sixteen Chinese patients with ONFH were consecutively enrolled in this cross-sectional study from January 2010 to December 2010. The Zung self-rating anxiety scale (SAS) and the Zung self-rating depression scale (SDS) were used to assess the prevalence of clinical anxiety and clinical depression. An additional questionnaire containing seventeen items of potential risk factors was completed by all patients. Binary logistic regression analysis was employed to reveal potential risk factors of anxiety and depression.

Results

The prevalence of clinical anxiety and clinical depression was 20.4% and 21.8% in Chinese young and middle-aged patients with ONFH, respectively. Binary regression analysis showed that independent risk factors correlated with high incidence of clinical anxiety included involved femoral head (OR = 3.168, 95% CI: 1.496 - 6.708) and stages of ONFH (OR_{IV-V / II} = 5.383, 95% CI: 1.664-17.416). Independent risk factors correlated with high incidence of depression included gender (OR = 2.853, 95% CI: 1.467-5.778), comorbid diseases (OR = 4.243, 95% CI: 1.940-9.278) and stages of the disease (OR _IV-V/II = 16.963, 95% CI: 4.404-65.331).

Conclusions

Patients with bilateral ONFH are inclined to have clinical anxiety, while female patients and patients with comorbid diseases might tend to get clinical depression. Advanced stages of ONFH are independent risk factors for both clinical anxiety and clinical depression.

ADAMTS-7 exhibits elevated expression in cartilage of osteonecrosis of femoral head and has a positive correlation with TNF- α and NF- κ B P65

ADAMTS-7 has been reported to exaggerate cartilage degeneration and to be associated with TNF-α and NF-κB signaling pathway. In this study we compared the expression of ADAMTS-7, TNF-α, and Phospho-NF-κB in patients with femoral neck fracture (FNF) and osteonecrosis of femoral head (ONFH) at different stages. We found that expression of ADAMTS-7, TNF-α, and Phospho-NF-κB was significantly upregulated in ONFH patients' articular cartilage and related to the pathogenesis of ONFH. Thus we conclude that ADAMTS-7 level appears to be positively associated with expression of TNF-α and Phospho-NF-κB P65 in cartilage, which may imply its association with cartilage destruction of ONFH.

Evaluation of electric field distribution in electromagnetic stimulation of human femoral head

Electromagnetic stimulation is a common therapy used to support bone healing in the case of avascular necrosis of the femoral head. In the present study, we investigated a bipolar induction screw system with an integrated coil. The aim was to analyse the influence of the screw parameters on the electric field distribution in the human femoral head. In addition, three kinds of design parameters (the shape of the screw tip, position of the screw in the femoral head, and size of the screw insulation) were varied. The electric field distribution in the bone was calculated using the finite element software Comsol Multiphysics. Moreover, a validation experiment was set up for an identical bone specimen with an implanted screw. The electric potential of points inside and on the surface of the bone were measured and compared to numerical data. The electric field distribution within the bone was clearly changed by the different implant parameters. Repositioning the screw by a maximum of 10 mm and changing the insulation length by a maximum of 4 mm resulted in electric field volume changes of 16% and 7%, respectively. By comparing the results of numerical simulation with the data of the validation experiment, on average, the electric potential difference of 19% and 24% occurred when the measuring points were at a depth of approximately 5 mm within the femoral bone and directly on the surface of the femoral bone, respectively. The results of the numerical simulations underline that the electro-stimulation treatment of bone in clinical applications can be influenced by the implant parameters.

How do radiologists evaluate osteonecrosis?

OBJECTIVES

Management of patients with osteonecrosis of the hip remains controversial and challenging. Because the prognosis and treatment are determined in large part by the stage and extent of the disease, it is important to use a reliable and efficient method for evaluation and staging. The objective of this study was to determine how musculoskeletal (MSK) radiologists evaluate osteonecrosis and whether this evaluation is adequate.

MATERIALS AND METHODS

A 12-part questionnaire was designed to determine how MSK radiologists evaluate patients with osteonecrosis of the femoral head (ONFH). This was sent to 888 members of the Society of Skeletal Radiology.

RESULTS

One hundred and twenty-one members responded to essentially all questions. Patients were evaluated using plain radiographs and MRI. All agreed that it is clinically important to determine the extent of necrosis and joint involvement, and 115 (95 %) stated that this should be part of the radiologists' evaluation. However, only 55 (46 %) said that in practice they used a specific system of classification, and most of these used the Ficat and Arlet classification, which does not indicate the extent of involvement. One hundred and seven (88 %) respondents included a simple visual estimate of the extent of involvement, and a small number added a specific measurement of lesion size. The majority indicated that they were infrequently consulted about which imaging studies should be obtained.

CONCLUSIONS

Although radiologists recognize the clinical importance of determining the extent of necrosis and joint involvement in patients with ONFH, in practice the methods used to evaluate these patients often do not accomplish this satisfactorily. The use of an effective classification, which includes both stage and extent of involvement, should be stressed, as it will lead to improved treatment of patients with ON. Physicians who order imaging studies for patients with ON should be encouraged to consult routinely with their radiology colleagues regarding which studies to request, as well as on the interpretation of these studies.

Bone impacted fibular free flap: a novel technique to increase bone density for dental implantation in osseous reconstruction

BACKGROUND

Fibular free flap (FFF) bone has thick cortical bone surrounding a fatty marrow. The cortex has sufficient density for dental implantation, but the marrow limits bone stock. A novel technique was devised to increase bone density: the bone-impacted fibular free flap (BIFFF). The purpose of this study was to: (1) describe the BIFFF technique; (2) evaluate the bone density of BIFFF; and (3) evaluate the stability/success of implants placed in BIFFFs.

METHODS

Patients undergoing maxillary/mandibular reconstruction with FFFs were prospectively enrolled from 1998 to 2008. Two cohorts were compared: BIFFF and nonmodified FFF. The main outcome was bone density as seen on CT scans. Primary dental implant stability was determined via Periotest.

RESULTS

Thirty-eight patients were included in this study. BIFFFs achieved higher bone density versus unmodified FFFs (p < .05). Greater primary dental implant stability occurred in BIFFFs (p < .05). One hundred percent of BIFFF and 59% of nonmodified FFF implants were successful at 1 year.

CONCLUSION

BIFFF increases reconstructed bone density, initial dental implant stability, and 1-year implant success.

Sclerotic lesions of the spine: MRI assessment

Sclerotic (T2 dark) lesions of the spine are infrequent and, as a result, these are often missed or misdiagnosed. Plain films may not be always available during magnetic resonance imaging (MRI) readout. Knowledge of such lesions and their imaging appearances on MRI evaluation is essential for a reader. Additionally, a systematic approach is important to accurately diagnose these lesions. In this article we discuss the various causes of spinal sclerotic lesions, describe their MRI characteristics with relevant case examples, and outline a systematic approach to their evaluation.

Use of zoledronic acid for treatment of chemotherapy related osteonecrosis in children and adolescents: a retrospective analysis

BACKGROUND

Osteonecrosis (ON) is a disabling complication of chemotherapy, especially steroids in children and adolescents. There are few reports in the literature of non-surgical management of ON. Patients with chemotherapy related ON, treated with zoledronic acid (ZA) were analyzed for clinical and radiological outcome.

METHODS

Retrospective chart review. Serial joint radiographs were performed to assess response and graded according to Association Research Circulation Osseous (ARCO) system. All patients were evaluated for bone turnover and bone mineral density (BMD) at set intervals.

RESULTS

Twenty children with ON were treated with ZA for median duration of 13 months (range 5-25) with median number of doses being 6 (2, 8). Five (25%) patients were pain free at the end of treatment and had minimal joint destruction on X-ray (ARCO score II); 5 (25%) underwent arthroplasty due to severe joint destruction and pain limiting activity (ARCO score III/IV); 10 (50%) reported ongoing pain with activity, none on regular analgesia. BMD analysis showed increase in lumbosacral BMD after 1 year of treatment. Compared to patients with ON of the knees, majority of patients with ON of the hips had radiological progression.

CONCLUSION

ZA was well tolerated and improved joint pain in the majority of patients. Despite treatment with ZA, most patients with ON of hips had progressive joint destruction requiring arthroplasty. Patients with ON of the knees appeared to have radiological stabilization. Novel treatment strategies should be considered to prevent this debilitating complication in survivors of childhood cancer.

Modified surgical techniques of free vascularized fibular grafting for treatment of the osteonecrosis of femoral head: results from a series of 407 cases

The goal for treatment of osteonecrosis of the femoral head (ONFH) is to relieve pain, preserve the contour of the femoral head, and delay the need for total hip arthroplasty. The free vascularized fibular grafting (FVFG) has been shown to support the subchondral architecture as well as restore local circulation for the necrotic femoral head in treatment of ONFH. This report aimed to present the clinical results of the use of a modified surgical technique of FVFG for treatment of ONFH. Four hundred and seven patients with 578 hips of ONFH were included. The patients' average age was 36.7 years old (ranging 19-55 years old). The disease was staged from II to V based on the Steinberg classification system. By the modified procedure, the vascularized fibular graft was harvested via a lateral incision with fibular osteotomy prior to the exposure of the vascular pedicle, and the removal of necrotic tissue and inset of graft were performed through an anterior approach. The operative time averaged 90 min for unilateral ONFH (ranging 75-110 min) and 190 min for simultaneous treatment of bilateral ONFH (ranging 160-230 min). The average length of follow-up was 5.0 years (ranging 3-10 years). The complications included one infection in one case, temporary loss of sensation of the thigh in eleven cases, and restricted motion of the great toe in nine cases. The Harris hip score of patients improved from 65.0 to 86.9 on average. Radiographic evaluation showed no changes in 331 hips (57.3%), improvement in 195 hips (33.7%) and necrosis progression in 52 hips (9.0%). Twenty-three hips (4.0%) in 20 patients had total hip arthroplasty during the period. These results show that the modified technique of the use of FVFG for treatment of ONFH yields similar postoperative results in comparison to the traditional method.

Accuracy and limitations of diagnostic methods for avascular necrosis of the hip

INTRODUCTION

Femoral head avascular necrosis (FHAVN) is the result of irreversible anoxia of the subchondral bone. The death of bone cells can cause articular collapse and pain, and in turn usually leads to degenerative arthritis. FHAVN is a common disorder, affecting mainly young male adults. Reliability, accuracy and prognostic value of any classification system are important in evaluation and treatment of FHAVN.

AREAS COVERED

Although in the past, scintigraphy and CT and more recently PET have been used for diagnosing AVN, currently the most important imaging methods included in the most widely used classification systems, consist of radiographs and magnetic resonance imaging (MRI). The latter is used in major classification systems for early detection (pre-radiographic stage) of FHAVN and for assessing lesion size and location before collapse of the articular surface occurs. The purpose of this review is to present the current data regarding the accuracy of the X-rays and MRI in diagnosing, monitoring and postoperative evaluation of FHAVN.

EXPERT OPINION

The author's opinion is that MRI may contribute to improve staging, investigate radiologically occult collapse, depict other causes of disability and pain, assess prognosis and evaluate treatment. Newer MRI techniques, such as diffusion-weighted imaging and perfusion imaging, have not yet provided additional and clinically useful information.

Combined tantalum implant with bone grafting for the treatment of osteonecrosis of the femoral head

BACKGROUND

The purpose of this study was to evaluate the short-term clinical outcome of using a tantalum implant in combination with bone grafting for the treatment of osteonecrosis of the femoral head.

METHODS

Sixty-nine patients with 94 osteonecrotic hips were treated with this method from March 2006 to March 2011. All the patients were treated with tantalum rod implantation in combination with bone grafting, and were followed for an average 35.4 months. Harris hip score and the survival rate were analyzed according to stage, etiology, and osteonecrosis part.

RESULTS

Patients with stage I and stage II diseases had significant greater Harris hip score improvement than patients having stage III disease (p < .05). The survival rate was also significantly higher in patients with stage I and stage II diseases than in patients having stage III disease (p < .05). Patients with type A and type B necrotic lesions had better recovery than patients with type C1 and type C2 having lateral column lesions (p < .05). No significant differences were detected in the clinical outcome among patients with different etiologies.

CONCLUSION

Combined tantalum implant with bone grafting provided good short-term clinical outcomes for early stage I and stage II patients with type A and type B necrotic lesions. However, this treatment modality was not so effective for patients with stage III or type C1 and type C2 necrotic lesions.

Are we evaluating osteonecrosis adequately?

PURPOSE

It is well recognised that to evaluate a patient with osteonecrosis of the femoral head (ONFH) adequately, it is necessary that the size of the infarct and the extent of femoral head joint involvement be indicated, in addition to the type or stage of the pathological process. The purpose of this study was to determine whether patients with ONFH are being evaluated adequately in studies published during the past 25 years and to see if any trends can be identified.

METHODS

Articles describing treatment of patients with ONFH, published between 1985 and 2011, were reviewed to determine the methods used to indicate the type and extent of pathology present on radiographs and magnetic resonance imaging (MRI) studies. The classification systems cited were identified and divided between those which indicated only the stage and those which indicated both stage and extent of involvement.

RESULTS

In 208 studies published between 1985 and 2011, specific classification systems were cited 237 times. During this period, non-quantitative systems, which only indicate stage, were cited 139 times (59 %) and quantitative systems, which indicate both stage and extent of involvement were cited 77 times (32 %). Between 2006 and 2011, non-quantitative systems were cited 30 times (48 %) and quantitative systems were cited 27 times (44 %).

CONCLUSIONS

During the past 25 years there has been a trend towards the use of more comprehensive and effective methods of evaluating patients with ONFH. However, during the past five years, approximately half of the published studies continued to use limited, non-quantitative methods of evaluation. This should be brought to the attention of the orthopaedic community. Future investigations and publications on ONFH should employ comprehensive methods of classification which include not only the stage of disease but also measurements of the size of the necrotic segment and the extent of femoral head and joint involvement.

Magnetic resonance imaging in children with sickle cell disease--detecting alterations in the apparent diffusion coefficient in hips with avascular necrosis

BACKGROUND

Avascular necrosis (AVN) is a common morbidity in children with sickle cell disease (SCD) that leads to pain and joint immobility. However, the diagnosis is often uncertain or delayed.

OBJECTIVE

To examine the ability of apparent diffusion coefficient (ADC) measurements on diffusion-weighted imaging to detect AVN in children with SCD.

MATERIALS AND METHODS

ADC values were calculated at the hips of normal children (n = 19) and children with SCD who were either asymptomatic with no known previous hip disease (n = 13) or presented for the first time with clinical symptoms of hip pathology (n = 12). ADC values were compared for differences among groups with and without AVN using non-parametric statistical methods.

RESULTS

The ADC values were elevated in the hips of children with AVN (median ADC = 1.57 × 10(-3) mm(2)/s [95% confidence interval = 0.86-2.10]) and differed significantly in pairwise comparisons (all P < 0.05) from normal children (0.74 [0.46-0.98]), asymptomatic children with SCD (0.55 [0.25-0.85]), and SCD children who had symptoms referable to their hips but did not show findings of hip AVN on conventional MRI or radiographs (0.46 [0.18-0.72]).

CONCLUSION

Children with sickle cell disease have elevated apparent diffusion coefficient values in their affected hips on initial diagnosis of avascular necrosis.

The use of an injectable calcium sulphate/calcium phosphate bioceramic in the treatment of osteonecrosis of the femoral head

PURPOSE

The purpose of our study is to describe the rationale, the surgical technique and the early clinical and radiographic results of the treatment of patients with early stage osteonecrosis of the femoral head (ONFH) by performing: core decompression, injection of autologous bone marrow concentrate and the use of a new composite injectable bone substitute (PRO-DENSE(®)), as a mechanical supplementation associated with decompression.

METHODS

The study included 37 hips (31 patients, 14 females, 17 males; mean age 43.9 years, range 24-56 years) with stages IC-IIIA ONFH. The outcome was determined by the changes in the Harris hip score (HHS), by progression in radiographic stages and by the need for hip replacement. The mean follow-up was 20.6 months (range 12-32 months).

RESULTS

At final follow-up the mean HHS increased from 68 points pre-operatively to 86 points post-operatively. The radiological results showed that 29 hips (78.4 %) improved or had no further collapse. The overall clinical success rate of the procedure was 86.5 %, with three conversions to THA, and a failure rate of only 3.3 % in the pre-collapse group.

CONCLUSIONS

We are encouraged by these early results using core decompression, injection of the autologous bone marrow concentrate and backfilling the defect with an injectable bioceramic for the treatment of early stages of ONFH; as far as a conclusion can be drawn from the current data, this treatment seems to relieve hip pain and prevent the progression of ONFH in the majority of the cases.

Stem cell- and growth factor-based regenerative therapies for avascular necrosis of the femoral head

Avascular necrosis (AVN) of the femoral head is a debilitating disease of multifactorial genesis, predominately affects young patients, and often leads to the development of secondary osteoarthritis. The evolving field of regenerative medicine offers promising treatment strategies using cells, biomaterial scaffolds, and bioactive factors, which might improve clinical outcome. Early stages of AVN with preserved structural integrity of the subchondral plate are accessible to retrograde surgical procedures, such as core decompression to reduce the intraosseous pressure and to induce bone remodeling. The additive application of concentrated bone marrow aspirates, ex vivo expanded mesenchymal stem cells, and osteogenic or angiogenic growth factors (or both) holds great potential to improve bone regeneration. In contrast, advanced stages of AVN with collapsed subchondral bone require an osteochondral reconstruction to preserve the physiological joint function. Analogously to strategies for osteochondral reconstruction in the knee, anterograde surgical techniques, such as osteochondral transplantation (mosaicplasty), matrix-based autologous chondrocyte implantation, or the use of acellular scaffolds alone, might preserve joint function and reduce the need for hip replacement. This review summarizes recent experimental accomplishments and initial clinical findings in the field of regenerative medicine which apply cells, growth factors, and matrices to address the clinical problem of AVN.

STEROID-INDUCED VERSUS CRYOINSULT-INDUCED FEMORAL HEAD OSTEONECROSIS: STATISTICAL MEASUREMENT OF HISTOLOGIC ABNORMALITY FOCALIZATION

Systematic studies of treatment options for femoral head osteonecrosis have been hindered by the lack of an animal model that mimics the human event of femoral head collapse. The (bipedal) emu model of osteonecrosis has proven to progress to collapse following an external insult. Since osteonecrosis clinically has multiple etiologies, various alternatives are seemingly appropriate to initiate lesions for research purposes. This study compared osteonecrosis initiated by a local cryoinsult, to that initiated by a large systemic dose of steroid (methylprednisolone acetate), and by a combination of steroid and cryoinsult. One year post-insult, the animals were sacrificed and their femoral heads harvested. A custom-written computer program was used to expedite analysis of the global distribution of histologically apparent osteonecrosis, as determined by the Ficat scale. Following whole-head analysis, grade distributions were calculated, and a measure of spatial clustering of histologic abnormality was calculated using Moran's I statistic. Normal femoral heads showed very small amounts of histological abnormality, and no significant spatial clustering. Femoral heads receiving isolated cryoinsult had a greater incidence of high-grade abnormality, as well as statistically significant spatial clustering of that abnormality. Steroid-only animals had a higher percentage of diffuse, low-grade abnormality. The group receiving both steroid and cryoinsult showed the highest overall abnormality, with statistically significant clustering of that high-grade abnormality. Cryoinsult, both in isolation and in combination with a steroid regimen, appeared necessary to mimic the clinically typical focal lesions of osteonecrosis.