Do modern techniques improve core decompression outcomes for hip osteonecrosis?

Bilateral idiopathic osteonecrosis of the femoral head: a case report with an emphasis on differential diagnosis, imaging, and treatment

OBJECTIVE

The purpose of this case report is to describe a patient with bilateral idiopathic osteonecrosis of the femoral head (ONFH), provide a discussion of differential diagnosis for anterior hip pain, imaging, and treatment recommendations for ONFH.

CLINICAL FEATURES

A 34-year-old man was initially treated by a chiropractic physician for low back pain. At the end of a three week trial of care, the patient's low back pain resolved. However, he reported a new complaint of mild left anterior hip stiffness. After re-examination, a homecare exercise program was prescribed. The patient returned 1 month later with substantial left anterior hip pain and walked with a noticeable limp. Radiography of the left hip demonstrated advanced ONFH. Magnetic resonance imaging of both hips demonstrated the extent of involvement of the left hip while incidentally revealing ONFH on the right.

INTERVENTION AND OUTCOME

A total hip arthroplasty was performed on the left hip and the right hip is being monitored without intervention.

CONCLUSION

Osteonecrosis of the femoral head is a challenging clinical problem with non-specific and wide-ranging signs and symptoms requiring clinicians to engage a cautious and comprehensive differential diagnosis. Prompt recognition ensures that appropriate treatment can be initiated in a timely manner and optimal patient outcomes achieved.

Management of femoral neck fractures in the young patient: A critical analysis review

Femoral neck fractures account for nearly half of all hip fractures with the vast majority occurring in elderly patients after simple falls. Currently there may be sufficient evidence to support the routine use of hip replacement surgery for low demand elderly patients in all but non-displaced and valgus impacted femoral neck fractures. However, for the physiologically young patients, preservation of the natural hip anatomy and mechanics is a priority in management because of their high functional demands. The biomechanical challenges of femoral neck fixation and the vulnerability of the femoral head blood supply lead to a high incidence of non-union and osteonecrosis of the femoral head after internal fixation of displaced femoral neck fractures. Anatomic reduction and stable internal fixation are essentials in achieving the goals of treatment in this young patient population. Furthermore, other management variables such as surgical timing, the role of capsulotomy and the choice of implant for fixation remain controversial. This review will focus both on the demographics and injury profile of young patients with femoral neck fractures and the current evidence behind the surgical management of these injuries as well as their major secondary complications.

Comparison of bone marrow mesenchymal stem cells and core decompression in treatment of osteonecrosis of the femoral head: a meta-analysis

The study aims to compare the clinical efficacy of core decompression (CD) and bone marrow mesenchymal stem cells (BMMSC) on the patients with osteonecrosis of the femoral head (ONFH). A detailed literature search of PubMed, MEDLINE and EMBASE, Springer, Elsevier Science Direct, Cochrane Library and Google scholar for all relevant papers published was performed. Pooled odds ratio (OR) or weighted mean differences (WMD) and 95% confidence interval (CI) were used to evaluate the clinical efficacy of CD and BMMSC with the clinical outcome on the patients with ONFH. A total of 219 hips in 4 studies were indentified in this current meta-analysis. The OR of 2 separate studies consisting of 115 hips (CD group 63 hips; BMMSC group 52 hips) of patients were pooled and suggested BMMSC group had significantly less number of progressed vascularized bone grafting events than CD group (OR = 0.11; 95% CI: 0.03~0.43; P < 0.01). In addition, WMD of other 2 separate studies consisting of 104 hips (CD group 52 hips; BMMSC group 52 hips) in patients were pooled, and significant differences (P < 0.01) in Harris Hip Score (HHS) were observed between these two treatment groups at the end of follow-up study, BMMSC group had significantly better clinical outcome than CD group (WMD = 8.69; 95% CI: 3.76~13.62; P < 0.01). BMMSC may perform a better therapeutic effect than CD on the patients with osteonecrosis of the femoral head.

Summary of the various treatments for osteonecrosis of the femoral head by mechanism: A review

Osteonecrosis of the femoral head (ONFH), also known as femoral head avascular necrosis, is a pathological state with a number of possible etiologies including steroid administration, alcohol abuse, traumatic events, vascular injury and idiopathic origins. ONFH causes a reduction in the vascular supply to the subchondral bone of the femoral head, which results in osteocyte death and the collapse of the articular surface. Treatments for ONFH include non-weight-bearing therapy, physical support, the promotion of osteoclast apoptosis, and the reduction of osteoblast and osteocyte apoptosis. The aim of the present review was to summarize the treatments for ONFH by mechanism from a new perspective and to describe the condition with an emphasis on treatment options.

Invasive electromagnetic field treatment in osteonecrosis of the femoral head: a prospective cohort study

Introduction :

The purpose of this prospective cohort study was to compare the surgical treatment of non-ONFH in adulthood by curettage and bone grafting with treatment by curettage and bone grafting in combination with invasive electromagnetic field treatment using Magnetodyn^®. This was assessed by examining whether electromagnetic field treatment has a positive additive effect on the clinical parameters modified Harris Hip Score according to Haddad, Cook and Brinker, Merle d'Aubigné hip score and visual analogue scale, and on the subsequent need for treatment by total hip arthroplasty.

Materials and Methodology :

The prospective, non-randomised study included 35 patients with unilateral or bilateral osteonecrosis of the femoral head. These were divided into two groups according to the surgical treatment regime and assessed over a 12-month follow-up period. The study group (Group 1) comprised 19 patients (14 men and 5 women) with a total of 22 non-ONFH, who underwent minimally invasive curettage, bone grafting and electromagnetic field treatment (Magnetodyn^®) by implantation of a bipolar induction screw. The control group (Group 2) comprised 16 patients (12 men and 4 women) with a total of 18 non-ONFH, who underwent minimally invasive curettage and bone grafting without Magnetodyn^® therapy. At the initial pre-operative examination and the 6 and 12-month follow-up, all patients were assessed by clinical examination and radiological monitoring, and by bilateral hip MRI. The clinical evaluation was based on the modified Harris Hip Score according to Haddad, Cook and Brinker, the Merle d`Aubigné hip score and the visual analogue scale (VAS).

Results :

At the time of follow-up, total hip arthroplasty (THA) had been performed in four patients in Group 1 (18%). In Group 2, four patients (22%) had received a THA (n.s.). Both procedures led to an improvement in the clinical scores (Harris Hip Score, Merle d`Aubigné score and VAS), although no significant difference was observed.

Conclusion :

The authors conclude that electromagnetic field treatment with Magnetodyn^®, using the special signal protocol applied here, as an adjunct to curettage and autologous bone grafting to treat non-ONFH, does not produce better clinical results and does not offer better prophylaxis for the avoidance of total hip arthroplasty over all ARCO stages.

Treatment of AVN using the induction chamber technique and a biological-based approach: indications and clinical results

OBJECTIVE

To determine the efficacy of core decompression (CD) technique combined with recombinant morphogenetic proteins, autologous mesenchymal stem cells (MSCs) and xenograft bone substitute into the necrotic lesion of the femoral head on clinical symptoms and on the progression of osteonecrosis of the femoral head.

PATIENTS AND METHODS

A total of 38 patients (40 hips) with early stage osteonecrosis of the femoral head were studied over a 4-year period.

RESULTS

CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute was associated with a significant reduction in both pain and joint symptoms and reduced the incidence of fractural stages. At 36 months, 33 patients achieved clinical and radiographic healing.

CONCLUSION

This long-term follow-up study confirmed that CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute may be an effective treatment for patients with early stage osteonecrosis of the femoral head.

Hip osteonecrosis: does prior hip surgery alter outcomes compared to an initial primary total hip arthroplasty?

The purpose of this study was to assess the clinical and radiographic outcomes of total hip arthroplasty (THA) in patients who had osteonecrosis to see if prior hip preserving surgery affected outcomes. Implant survivorship, Harris hip scores, and radiographic outcomes were compared between 87 patients (92 hips) who had undergone prior hip preserving procedures and 105 patients (121 hips) who had only undergone THA. Patients were also sub-stratified into low- and high-risk groups for osteonecrosis. At a mean follow-up of 75 months, there were no significant differences in survivorship, clinical, and radiographic outcomes among the cohorts. Higher revision rates were associated with patients who were in the high-risk group. The authors believe that hip joint preserving procedures may not adversely affect the outcomes of later THA in patients with osteonecrosis.

Osteonecrosis of the knee - which joint preservation procedures work?

There is no consensus with respect to the best procedures to preserve the knee joint in patients with osteonecrosis of the knee. We performed a systematic review of the literature between 1999 and 2012. Only 10 of 1057 studies met our inclusion criteria. Core decompression prevented additional surgical treatment in pre-collapse knees with a failure rate of 10.4% (7 of 67 knees). Autogenous and osteochondral grafts decreased the need for additional surgery in both pre-collapse (0%, 20 of 20) and post-collapse knees (10.5%, 8 of 76 knees). Although these results are quite promising multi-center randomized trials are needed to identify the optimal procedures to treat this disease.

Core decompression in combination with nano-hydroxyapatite/polyamide 66 rod for the treatment of osteonecrosis of the femoral head

BACKGROUND

The aim of this study was to investigate the effectiveness of core decompression in combination with a nano-hydroxyapatite/polyamide 66 (n-HA/PA66) rod and a porous bioglass bone graft for the treatment of osteonecrosis of the femoral head (ONFH).

METHODS

Sixty-four patients (84 hips) with ONFH were allocated to a program of either core decompression (CD) in combination with a n-HA/PA66 rod and a porous bioglass bone graft (treatment group) or CD with an autologous cancellous bone graft (control group). Clinical and radiographic retrospective follow-ups were performed on all patients with the prospectively collected data.

RESULTS

The overall clinical failure rate in the treatment group (9/38, 23.68%) was lower than that of the control group (24/46, 52.17%) (p < 0.05). Harris hip scores (HHS) were significantly increased in both groups post-surgery (p < 0.05). There was a significant difference between the two groups on HHS improvement for Steinberg IIC and IIIA (p < 0.05 and p < 0.001, respectively). The visual analogue scale (VAS) was significantly decreased in both groups post-surgery (p < 0.05). Especially, significant difference in the VAS improvement was observed between the groups for IIB, IIC and IIIA (p < 0.05, p < 0.05 and p < 0.01, respectively).

CONCLUSIONS

Core decompression combined with the implantation of a n-HA/PA66 rod and a bioglass bone graft can significantly decrease hip pain, improve hip function, and prevent the collapse of the femoral head in patients with ONFH. As the effectiveness of this approach appears to vary with Steinberg stage, we suggest that this treatment procedure may be suitable for patients with early to middle stage ONFH.

Arthroscopic-assisted core decompression for osteonecrosis of the femoral head

The management of pre-collapse osteonecrosis of the femoral head is controversial. Core decompression is a technique that theoretically decreases the intraosseous pressure of the femoral head, resulting in a local vascularized healing response. Its efficacy has been shown in delaying early subchondral collapse. We describe the technique of arthroscopic-assisted core decompression of the femoral head for osteonecrosis. The advantages of this technique include evaluation of the presence or absence of articular cartilage injury, subchondral collapse, and guidance during reaming and curettage. It also allows the ability to address any concomitant soft-tissue or bony pathology associated with or in addition to the osteonecrotic lesion.

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.

Primary bone marrow oedema syndromes

MRI scanning in patients with rheumatological conditions often shows bone marrow oedema, which can be secondary to inflammatory, degenerative, infective or malignant conditions but can also be primary. The latter condition is of uncertain aetiology and it is also uncertain whether it represents a stage in the progression to osteonecrosis in some patients. Patients with primary bone marrow oedema usually have lower limb pain, commonly the hip, knee, ankle or feet. The diagnosis is one of exclusion with the presence of typical MRI findings. Treatment is usually conservative and includes analgesics and staying off the affected limb. The natural history is that of gradual resolution of symptoms over a number of months. Evidence for medical treatment is limited, but open-label studies suggest bisphosphonates may help in the resolution of pain and improve radiological findings. Surgical decompression is usually used as a last resort.

Multiple drilling compared with standard core decompression for avascular necrosis of the femoral head in sickle cell disease patients

INTRODUCTION

Sickle cell disease (SCD) is the most common cause of avascular necrosis of femoral head (ANFH) in childhood. Advances in medical treatment led to improved life expectancy of such patients. SCD-related ANFH frequently progress to total collapse of the femoral head necessitating hip replacement. However, SCD patient are at more risk of intra- and post-operative complications and suboptimal outcome of total hip arthroplasty. Hence, it is imperative to preserve the femoral head as long as possible.

PATIENTS AND METHODS

Between September 1992 and June 2007, 94 core decompression procedures were done to SCD patients who had modified Ficat stage I, IIA and IIB ANFH. Sixty one patients underwent a classical 8-mm drilling and 33 patients underwent 3.2-mm diameter MD technique. Patients were followed up for minimum of 2 years and were evaluated for clinical and Harris Hip Score improvement and for radiological progression.

RESULTS

All 19 hips that had Ficat stage I had significant reduction of pain and improvement of Harris Hip Score. No patient has required further surgery. Among the 39 hips with Ficat IIA at time of procedure, 80 % of hips which underwent CD and 78 % of MD cases had significant reduction of pain and improvement of HHS. Those patients showed no radiographic progression of the disease. The remaining, 20 % CD and 22 % MD eventually progressed radiologically to grade III or grade IV and had HHS less than 75 at last visit. In the 36 cases with Ficat IIB, 52 % CD and 52.8 % MC had significant reduction of pain and improvement of HHS. The rest showed no improvement in pain and function, and progressed to stage IV; 11 of them underwent THA and one patient refused surgery.

CONCLUSION

While multiple drilling is safer and less invasive than single coring in SCD, there is no statistically significant difference in outcome or complication rate between both procedures done for ANFH in patients with SCD.

Core decompression and alendronate treatment of the osteonecrotic rat femoral head: computer-assisted analysis

Femoral head avascular necrosis is a process leading to femoral head deformity and osteoarthritic changes in the hip joint. Alendronate slows down bone resorption and remodelling in rats, while core decompression hastens the healing processes. We evaluated the influence of daily alendronate treatment on the rat femoral head shape after surgical osteonecrosis with core decompression, compared with controls. No differences were found in shape factor and femoral head height/length ratios. It was concluded that alendronate treatment slows down the process of replacing osteonecrotic bone by new bone and prevents early immature new bone collapse resulting from early revascularization because of core decompression.

Umbrella-shaped, memory alloy femoral head support device for treatment of avascular osteonecrosis of the femoral head

PURPOSE

Avascular necrosis (AVN) of the femoral head is a common orthopaedic disease that is difficult to treat. The purpose of this study was to explore the preliminary efficacy of a self-designed umbrella-shaped memory alloy femoral head support device in the treatment of adult patients with avascular osteonecrosis of the femoral head.

METHODS

The minimally-invasive approach involved curettage of the necrotic tissue of the femoral head, and a self-designed umbrella-shaped, memory alloy femoral head support device was implanted into the collapsed necrotic area to support the collapsed femoral head. Autologous iliac bone and artificial bone were implanted into the support device for the treatment of adult patients with avascular osteonecrosis of the femoral head.

RESULTS

The clinical device was used in ten patients and 18 hip joints. The support device failed in one hip joint, which subsequently underwent joint replacement surgery, and the remaining 17 implanted devices were followed up for four to 19 months. The 17 postoperative hip joints were evaluated using the percent-efficacy evaluation method for avascular osteonecrosis of the femoral head in adult patients, and the efficacy rate was 82.35 %.

CONCLUSION

The umbrella-shaped femoral head support device can be used in Ficat stage I, stage II, and stage III adult patients with avascular osteonecrosis of the femoral head.

Core decompression and implantation of bone marrow mononuclear cells with porous hydroxylapatite composite filler for the treatment of osteonecrosis of the femoral head

BACKGROUND

Implanted bone marrow mononuclear cells (BMMCs) may promote both osteogenesis and angiogenesis in the femoral head. The aim of this study was to investigate the effectiveness of core decompression and implantation of BMMCs with porous hydroxyapatite bone filler for the treatment of osteonecrosis of the femoral head (ONFH).

METHODS

Patients with ONFH underwent core decompression and implantation of nano-hydroxyapatite/polyamide bone filler with or without BMMCs. Primary outcomes were changes in Harris hip and visual analogue scale (VAS) pain scores. Secondary outcomes included radiological and clinical success rates, adverse events, and complications.

RESULTS

Demographic/baseline characteristics were similar between groups (BMMC, n = 17 with 26 ONFH hips; control, n = 17 with 27 ONFH hips). Harris hip scores were significantly increased (P < 0.05) in both groups of patients after surgery (last follow-up). The magnitude of increase was significantly greater in the BMMC as compared with the control group (28.6 ± 0.5 vs. 18.4 ± 1.7 %, P < 0.001). VAS scores were significantly decreased (P < 0.05) in both groups after surgery (last follow-up). The magnitude of decrease was significantly greater in the BMMC as compared with the control group (-66.3 ± 1.4 vs. -51.7 ± 2.9 %, P < 0.001). Radiological and clinical success rates were significantly higher in the BMMC as compared with the control group (82.5 vs. 40.7 % and 75.4 vs. 37.0 %, respectively, P < 0.001). Postoperative collapse of the femoral head was less common in the BMMC as compared with the control group (17.5 vs. 59.3 %, P < 0.01).

CONCLUSIONS

Both core decompression with or without implantation of BMMC are effective treatment for ONFH. However, core decompression with implantation of BMMCs and porous hydroxyapatite bone filler may be a more effective treatment for ONFH.

Treatment of femoral head osteonecrosis with advanced cell therapy in sheep

BACKGROUND

The purpose of this study was to evaluate the efficacy of core decompression associated with advanced cell therapy for the treatment of femoral head osteonecrosis in an established sheep model.

METHODS

Early stage osteonecrosis of the right hip was induced cryogenically in 15 mature sheep. At 6 weeks, the sheep were divided into three groups, Group A: core decompression only; Group B: core decompression followed by implantation of an acellular bone matrix scaffold; Group C: core decompression followed by implantation of a cultured BMSC loaded bone matrix scaffold. At 12 weeks, MRI hip studies were performed and then the proximal femur was harvested for histological analysis.

RESULTS

In the group of advanced cell therapy, Group C, there was a tendency to higher values of the relative surface of newly formed bone with a mean of 20.3 versus 11.27 % in Group A and 13.04 % in Group B but it was not statistically significant. However, the mean relative volume of immature osteoid was 8.6 % in Group A, 14.97 in Group B, and 53.49 % in Group C (p < 0.05), revealing a greater capacity of osteoid production in the sheep treated with BMSCs. MRI findings were not conclusive due to constant bone edema artifact in all cases.

CONCLUSIONS

Our findings indicate that a BMCSs loaded bone matrix scaffold is capable of stimulating bone regeneration more effectively than isolated core decompression or in association with an acellular scaffold in a preclinical femoral head osteonecrosis model in sheep.

There are many potential medical therapies for atraumatic osteonecrosis

Atraumatic osteonecrosis is a common complication of SLE and is seen in other connective tissue diseases, in patients treated with high doses of CSs, in HIV-infected patients and in alcoholic patients. Standard care is confined to analgesia, core decompression if the condition is early and affects the femoral head and joint replacement. However, consideration of the underlying biological mechanisms leads to the recognition of many potential therapies that might either prevent progression or, even, reverse the process if it is not yet too far advanced. These potential therapies merit detailed consideration. Critical points are that (i) histopathological evidence shows that the initial cellular event is apoptosis of osteocytes; and (ii) another requisite, as homeostasis requires that death and rebirth of osteocytes be balanced, is an accompanying inadequate proliferative capacity of osteoblasts. Thus, a logical approach to treatment includes measures that (i) reduce apoptosis of osteocytes and (ii) enhance proliferation of osteoblasts/pre-osteoblasts. Measures to reduce the ongoing apoptosis of osteocytes require reinforcing the effects of members of the Bcl-2 family (Bcl-2 itself and Mcl-1), the Wnt/catenin pathways (using an available sclerostin antibody) and HSPs (by application of local heat using US, deep wave diathermy or infrared), as well as administration of bisphosphonates and nitrates. Measures to enhance proliferation of osteoblasts/pre-osteoblasts include the use of stem cells, extracorporeal shock wave therapy, aspirin, the proteosome inhibitor bortezomib, melatonin and application of local heat. Use of VEGF would encourage proliferation of blood vessels and osteogenesis. Certain drugs that inhibit osteoblast proliferation should be avoided, including NSAIDs, serotonin reuptake inhibitors and thiazolidinediones.

Core decompression combined with implantation of a demineralised bone matrix for non-traumatic osteonecrosis of the femoral head

INTRODUCTION

Core decompression is the standard surgical procedure in the treatment of early stage non-traumatic osteonecrosis of the femoral head (ONFH). However, there is still a debate whether decompression in combination with supplementary augmentation by bone grafts, growth factors, or cell implementation is superior to conventional decompression alone. This study evaluated patients after core decompression combined with an augmentation by a demineralised bone matrix, and particularly aimed to report long-term conversion rates to total hip replacement (THR).

MATERIALS AND METHODS

14 patients with 18 hips suffering from ONFH (Ficat stage I-IIB) underwent this surgical procedure. All patients underwent radiographic and MRI investigations at baseline and at follow-up periods of 12 and 24 months. The clinical follow-up was done using the Merle d'Aubigné-score for an average period of 9 years after surgery.

RESULTS

14 of the 18 subjects (77 %) achieved at least a good clinical result after 2 years. The Merle d'Aubigné-score improved significantly after 12 (p = 0.0001) and 24 months (p = 0.0002). However, the MRI volumetric analysis showed an increased necrotic bone volume from 3.16 ± 0.54 to 3.88 ± 0.62 cm(3) (p = 0.04). Within 9 years, 13 out of 18 cases (72 %) required further surgery by THR. Only 7 out of 18 subjects (39 %) reported an ongoing postoperative clinical benefit, and would retrospectively redo the same surgical approach again. The five patients that did not require THR were still satisfied after 9 years.

CONCLUSIONS

In patients with early- stage femoral head osteonecrosis core decompression combined with the implantation of a demineralised bone matrix leads to a limited, temporary pain relief as seen in core decompression alone. However, long-term results were not encouraging with a high rate of conversion to arthroplasty. Therefore, core decompression with implantation of a demineralised bone matrix may be not appropriate to avoid THR in the long term.

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.

Early results of a novel technique using multiple small tantalum pegs for the treatment of osteonecrosis of the femoral head

The introduction of a trabecular tantalum rod has been proposed for the management of early-stage osteonecrosis of the femoral head but serves as a single-point of support of the necrotic lesion. We describe a technique using two or three 4.2 mm (or later 4.7 mm) tantalum pegs for the prevention of collapse of the necrotic lesion. We prospectively studied 21 patients (26 hips) with non-traumatic osteonecrosis of the femoral head treated in this manner. Of these, 21 patients (24 hips) were available for radiological and clinical evaluation at a mean follow-up of 46 months (18 to 67). Radiological assessment showed that only eight hips deteriorated according to the Association Research Circulation Osseous classification, and four hips according to the Classification of the Japanese Investigation Committee of Health and Welfare. Functional improvement was obtained with an improvement in the mean Harris hip score from 65.2 (33.67 to 95) to 88.1 (51.72 to 100), the mean Merle D’Aubigné-Postel score from 13 (6 to 18) to 16 (11 to 18), a mean visual analogue score for pain from 5.2 (0 to 9.5) to 2.6 (0 to 7), and the mean Short-Form 36 score from 80.4 (56.8 to 107.1) to 92.4 (67.5 to 115.7). Of these 24 hips followed for a minimum of 18 months, three were considered as failures at the final follow-up, having required total hip replacement. One of the hips without full follow-up was also considered to be a failure. In more than two-thirds of the surviving hips a satisfactory clinical outcome was achieved with promising radiological findings. The estimated mean implant survival was 60 months (95% confidence interval 53.7 to 66.3).

Which factors influence preservation of the osteonecrotic femoral head?

BACKGROUND

Although surgeons use many procedures to preserve the femoral head in patients with hip osteonecrosis, there is no consensus regarding the best procedure.

QUESTIONS/PURPOSES

We raised the following questions: (1) Is one surgical treatment preferred based on published data? (2) What are the rates of radiographic progression or conversion to THA after treatment of pre- and postcollapse hips? (3) Does lesion size in the femoral head influence progression? And (4) does the extent of involvement of the weightbearing surface of the femoral head influence outcome?

METHODS

We searched MEDLINE and Scopus for articles published between 1998 and 2010. We included only articles assessing an operative intervention for hip osteonecrosis and having a level of evidence of I to IV. We included 54 of the 488 reviewed manuscripts.

RESULTS

No procedure was superior to others. In pre- and postcollapse hips, 264 of 864 hips (31%) and 419 of 850 hips (49%), respectively, exhibited radiographic disease progression. There were lower failure rates when the lesion involved less than 15% of the femoral head or had a necrotic angle of less than 200° (14%-25%) and when the osteonecrotic lesion involved only the medial 1/3 of the weightbearing surface (4.6%).

CONCLUSIONS

The best treatment of precollapse lesions is difficult to determine due to the limitations of the available literature. However, the data suggest operative intervention prevents collapse of small lesions of the femoral head or when there is a limited amount of the weightbearing surface involved. Patients with head collapse have a high progression rate after a femoral head-saving procedure.

Treatment of early stage osteonecrosis of the femoral head with autologous implantation of bone marrow-derived and cultured mesenchymal stem cells

BACKGROUND

Treatment of early-stage osteonecrosis of the femoral head (ONFH) with autologous implantation of iliac crest bone marrow-derived mononuclear cells, which contain tens of thousands of bone marrow mesenchymal stem cells (BMMSCs), recently achieved a promising outcome.

METHODS

One hundred patients with early-stage ONFH were recruited and randomly assigned to BMMSC treatment or core decompression (CD) treatment. Each BMMSC-treated hip received femoral head (FH) implantation of 2×10(6) autologous subtrochanteric bone marrow-derived and ex vivo expanded BMMSCs. The radiographic stage of ONFH according to the Association Research Circulation Osseous classification, Harris hip score (HHS), and the volume of the necrotic lesion or the low signal intensity zone (LowSIZ) in the FH were assessed before and 6, 12, 24, and 60 months after the initial operation.

RESULTS

Sixty months after the operation, only 2 of the 53 BMMSC-treated hips progressed and underwent vascularized bone grafting. In CD group, 7 hips lost follow-up, and 10 of the rest 44 hips progressed and underwent vascularized bone grafting (5 hips) or total hip replacement (5 hips). Compared with the CD group, BMMSC treatment significantly improved the HHS as well as decreased the volume of femoral head LowSIZ of the hips preoperatively classified at stage IC, IIB, and IIC (P<0.05, respectively; stage IIA, P=0.06, respectively). No complication was observed in both treatment groups.

CONCLUSIONS

Ex vivo expansion of autologous BMMSCs can reliably provide a greater number of BMMSCs for FH implantation. This intervention is safe and effective in delaying or avoiding FH collapse, which may necessitate total hip replacement.

Autologous bone marrow cell implantation in the treatment of non-traumatic osteonecrosis of the femoral head: Five year follow-up of a prospective controlled study

OBJECTIVE

To determine the efficacy of bone marrow cell implantation into the necrotic lesion of the femoral head on clinical symptoms and the progression of osteonecrosis of the femoral head in comparison with core decompression.

METHODS

We studied nineteen patients and twenty four hips with early stage osteonecrosis of the femoral head. The hips were allocated to either core decompression only or core decompression and implantation of bone marrow cells. Both patients and assessors were blind with respect to treatment group assignment. The primary outcomes were clinical symptoms and disease progression.

RESULTS

Bone marrow implantation afforded a significant reduction in pain and in joint symptoms and reduced the incidence of fractural stages. At 60 months, eight of the eleven hips in the control group had deteriorated to the fractural stage whereas only three of the thirteen hips in the bone marrow graft group had progressed to that stage. Survival analysis showed a significant difference in the time to failure between the two groups at 60 months. Patients had only minor side-effects after the treatments.

CONCLUSIONS

This long term follow-up study confirmed that implantation of autologous bone marrow cells in the necrotic lesion might be an effective treatment for patients with early stages of osteonecrosis of the femoral head.

Management of osteonecrosis in children and young adults with acute lymphoblastic leukaemia

Osteonecrosis is a disabling complication in children and young adults with acute lymphoblastic leukaemia. It can affect any or multiple joints but the hip and knee are most frequently involved and a cause of long-term disability. The problem is almost exclusively that of older children and young adults of whom over 70% have asymptomatic changes on screening magnetic resonance imaging and 15-20% have resulting symptoms. Dexamethasone is associated with a higher risk than prednisolone in US but not European or UK trials and alternate week scheduling of dexamethasone in the intensification course is associated with a lower risk than a continuous 3-week schedule in US trials. Genetic factors and obesity contribute to the risk, as do metabolic abnormalities caused by drugs, such as asparaginase, which increase tissue exposure to steroids. Management is primarily supportive but a minority of patients require surgical intervention including replacement of the affected joint. A variety of surgical techniques and, latterly, bisphophonates, have been tried to prevent progression but their efficacy remains uncertain. Whether patients should continue to receive steroids after diagnosis of osteonecrosis is uncertain but most trial investigators recommend stopping them after completion of the intensification phase of treatment.

Core decompression for juvenile osteonecrosis

Core decompression may be used as adjunct for treatment in some cases of Legg-Calvé-Perthes disease (LCPD). The primary application is for patients with onset at 12 years of age or older. We recommend classifying these older patients as idiopathic juvenile osteonecrosis and treating them similarly to adults with avascular necrosis. Juvenile osteonecrosis may benefit from core decompression combined with shelf acetabuloplasty during the early stages of necrosis. Younger children with LCPD may benefit from decompression by fenestration of the femoral head. Experience in adult-onset osteonecrosis and our early experience suggest that some patients may benefit from these adjunctive treatments.

Impaired bone healing in rabbits with steroid-induced osteonecrosis

Corticosteroids are prescribed for the treatment of many medical conditions and their adverse effects on bone, including steroid-associated osteoporosis and osteonecrosis, are well documented. Core decompression is performed to treat osteonecrosis, but the results are variable. As steroids may affect bone turnover, this study was designed to investigate bone healing within a bone tunnel after core decompression in an experimental model of steroid-associated osteonecrosis. A total of five 28-week-old New Zealand rabbits were used to establish a model of steroid-induced osteonecrosis and another five rabbits served as controls. Two weeks after the induction of osteonecrosis, core decompression was performed by creating a bone tunnel 3 mm in diameter in both distal femora of each rabbit in both the experimental osteonecrosis and control groups. An in vivo micro-CT scanner was used to monitor healing within the bone tunnel at four, eight and 12 weeks postoperatively. At week 12, the animals were killed for histological and biomechanical analysis.

In the osteonecrosis group all measurements of bone healing and maturation were lower compared with the control group. Impaired osteogenesis and remodelling within the bone tunnel was demonstrated in the steroid-induced osteonecrosis, accompanied by inferior mechanical properties of the bone.

We have confirmed impaired bone healing in a model of bone defects in rabbits with pulsed administration of corticosteroids. This finding may be important in the development of strategies for treatment to improve the prognosis of fracture healing or the repair of bone defects in patients receiving steroid treatment.

The natural history of untreated asymptomatic osteonecrosis of the femoral head: a systematic literature review

BACKGROUND

An asymptomatic hip with osteonecrosis is typically discovered as the contralateral hip of a patient with one symptomatic joint. Treatment of the asymptomatic hip is controversial. While some authors claim a benign natural history, others have reported a rate of femoral head collapse exceeding 50%. The purpose of this report was to systematically review the published literature regarding asymptomatic osteonecrosis of the femoral head to evaluate the overall prevalence of progression to symptomatic disease and/or femoral head collapse as well as to determine whether various radiographic and demographic factors influence progression of the disorder.

METHODS

A comprehensive literature search was performed to identify prognostic studies evaluating asymptomatic hip osteonecrosis. Demographic, radiographic, and outcome data were extracted from all relevant studies. The prevalence of progression to symptomatic disease and/or femoral head collapse was determined. Next, outcomes were stratified by lesion size, lesion location, radiographic stage, associated risk factors and/or disease, and the level of evidence of the study.

RESULTS

Sixteen studies that included a total of 664 hips were available for an analysis of outcomes. Overall, 394 hips (59%) had progression to symptoms or collapse. Differences in outcomes based on lesion size, lesion location, and radiographic stage at the time of diagnosis were seen. Small, medially located lesions had the best prognosis, with a prevalence of collapse of <10%. Patients with sickle cell disease had the highest frequency of progression, and those with a history of systemic lupus erythematosus had the most benign course.

CONCLUSIONS

Data extracted from previously published studies suggest that asymptomatic osteonecrosis has a high prevalence of progression to symptomatic disease and femoral head collapse. While small, medially located lesions have a low rate of progression, the natural history of asymptomatic medium-sized, and especially large, osteonecrotic lesions is progression in a substantial number of patients. For this reason, it may be beneficial to consider joint-preserving surgical treatment in asymptomatic patients with a medium-sized or large, and/or laterally located, lesion.

Osteonecrosis of the humeral head

Osteonecrosis of the humeral head is considerably less common than osteonecrosis of the hip. However, as in the hip, the interaction between a genetic predisposition and certain risk factors may lead to increased intraosseous pressure, loss of circulation, and eventual bone death. The most common risk factor remains corticosteroid use, which accounts for most reported cases. Radiographic staging and measurement of lesion size are predictive of disease progression and can be used to determine appropriate intervention. Recent studies have reported the use of various treatment modalities such as pharmacologics, core decompression with small-diameter drilling, arthroscopic-assisted core decompression, and bone grafting. Prospective, randomized studies are needed to determine the efficacy of these joint-preserving procedures. Newer resurfacing techniques have a role in treating articular surface loss. Hemiarthroplasty and total shoulder arthroplasty are recommended for patients with end-stage disease.

Current literature: an educational tool to study osteonecrosis for the Orthopaedic In-Training Examination?

The Orthopaedic In-Training Examination (OITE) is used to evaluate the knowledge of residents and focuses on relevant information supported by current scientific literature. The purpose of this study was to assess the relevance of current literature as a study tool for the exam, especially for osteonecrosis-related material. A systematic review was conducted of the OITE and relevant journals to compare the proportion and characterization of questions and published studies related to osteonecrosis and other frequently tested subject areas over a 5-year period (2002 to 2006). This review suggests that the OITE and literature are generally similar in content. However, there may be some differences, especially in subspecialty journals, due to the emphasis of a specific subject area and non-validated procedures which makes them a less preferred resource for OITE preparation.