Aims. The value of core decompression (CD) in the treatment of osteonecrosis of the femoral head (ONFH) remains controversial. We conducted a systematic review and meta-analysis to evaluate whether CD combined with other treatments could improve the clinical and radiological outcomes of ONFH patients compared with CD alone. Methods. We searched the PubMed, Embase, Web of Science, and Cochrane Library databases until June 2020. All randomized controlled trials (RCTs) and clinical controlled trials (CCTs) comparing CD alone and CD combined with other measures (CD + cell therapy, CD + bone grafting, CD + porous tantalum rod, etc.) for the treatment of ONFH were considered eligible for inclusion. The primary outcomes of interest were Harris Hip Score (HHS), ONFH stage progression, structural failure (collapse) of the femoral head, and conversion to total hip arthroplasty (THA). The pooled data were analyzed using Review Manager 5.3 software. Results. A total of 20 studies with 2,123 hips were included (CD alone = 768, CD combined with other treatments = 1,355). The combination of CD with other therapeutic interventions resulted in a higher HHS (mean difference (MD) = 6.46, 95% confidence interval (CI) = 2.10 to 10.83, p = 0.004) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (MD = −10.92, 95% CI = -21.41 to -4.03, p = 0.040) and a lower visual analogue scale (VAS) score (MD = −0.99, 95% CI = -1.56 to -0.42, p < 0.001) than CD alone. For the rates of disease stage progression, 91 (20%) progressed in the intervention group compared to 146 (36%) in the control group (odds ratio (OR) = 0.32, 95% CI = 0.16 to 0.64, p = 0.001). In addition, the intervention group had a more significant advantage in delaying femoral head progression to the collapsed stage (OR = 0.32, 95% CI = 0.17 to 0.61, p < 0.001) and reducing the odds of conversion to THA (OR = 0.35, 95% CI = 0.23 to 0.55, p < 0.001) compared to the control group. There were no serious adverse events in either group. Subgroup analysis showed that the addition of cell therapy significantly improved clinical and radiological outcomes compared to CD alone, and this approach appeared to be more effective than other therapies, particularly in precollapse (stage I to II) ONFH patients. Conclusion. There was marked heterogeneity in the studies. There is a trend towards improved clinical outcomes with the addition of stem cell therapy to CD. Cite this article: Bone Joint Res 2021;10(7):445–458

Aims. Osteonecrosis (ON) can cause considerable morbidity in young people who undergo treatment for acute lymphoblastic leukaemia (ALL). The aims of this study were to determine the operations undertaken for ON in this population in the UK, along with the timing of these operations and any sequential procedures that are used in different joints. We also explored the outcomes of those patients treated by core decompression (CD), and compared this with conservative management, in both the pre- or post-collapse stages of ON. Methods. UK treatment centres were contacted to obtain details regarding surgical interventions and long-term outcomes for patients who were treated for ALL and who developed ON in UKALL 2003 (the national leukaemia study which recruited patients aged 1 to 24 years at diagnosis of ALL between 2003 and 2011). Imaging of patients with ON affecting the femoral head was requested and was used to score all lesions, with subsequent imaging used to determine the final grade. Kaplan-Meier failure time plots were used to compare the use of CD with non surgical management. Results. Detailed information was received for 85 patients who had developed ON during the course of their ALL treatment. A total of 206 joints were affected by ON. Of all joints affected by ON, 21% required arthroplasty, and 43% of all hips affected went on to be replaced. CD was performed in 30% of hips affected by ON. The majority of the hips were grade 4 or 5 at initial diagnosis of ON. There was no significant difference in time to joint collapse between those joints in which CD was performed, compared with no joint-preserving surgical intervention. Conclusion. There is a high incidence of surgery in young people who have received treatment for ALL and who have developed ON. Our results suggest that CD of the femoral head in this group of patients does not delay or improve the rates of femoral head survival. Cite this article: Bone Joint J 2021;103-B(3):589–596

Thirty shoulders, in 20 patients, which had undergone core decompression for symptomatic avascular necrosis of the humeral head were reviewed 2 to 14 years later (average 5.6). Twenty-two showed good or excellent clinical results; the other eight shoulders had required arthroplasty. All 14 shoulders with stage I or II radiological changes (Ficat and Arlet 1980) at operation had good or excellent results. We advocate early core decompression for symptomatic avascular necrosis of the humeral head

We performed 41 core decompressions in 32 patients for stage I or stage II osteonecrosis of the femoral head. The intra-osseous pressure at the intertrochanteric level was raised in 28 (68%) and there was histological confirmation of necrosis in 36 hips (88%). After a follow-up of 10 to 84 months (mean 31) nine of the 12 stage I hips (75%) showed significant clinical or radiological deterioration; no evidence of necrosis had been found in the core specimens of the other three hips. Of the 29 hips in stage II, 25 (86%) showed significant radiological deterioration, and only five (17%) had improved clinically. We believe that once necrosis has occurred, core decompression will not significantly influence the subsequent course of the disease

Aims. One method of femoral head preservation following avascular necrosis (AVN) is core decompression and insertion of a tantalum rod. However, there may be a high failure rate associated with this procedure. The purpose of this study was to document the clinical and radiological outcomes following total hip arthroplasty (THA) subsequent to failed tantalum rod insertion. Patients and Methods. A total of 37 failed tantalum rods requiring total hip arthroplasty were identified from a prospective database. There were 21 hips in 21 patients (12 men and nine women, mean age 37 years, 18 to 53) meeting minimum two year clinical and radiographic follow-up whose THAs were carried out between November 2002 and April 2013 (mean time between tantalum rod implantation and conversion to a THA was 26 months, 6 to 72). These were matched by age and gender to individuals (12 men, nine women, mean age 40 years, 18 to 58) receiving THA for AVN without prior tantalum rod insertion. Results. There were no functional outcome differences between the two groups. Tantalum residue was identified on all post-operative radiographs in the tantalum group. Linear wear rates were comparable between groups with no evidence of catastrophic wear in either group. Conclusion. In the short term, tantalum rod implantation does not demonstrate an adverse effect on subsequent total joint replacement surgery. There is however, a high rate of retained tantalum debris on post-operative radiographs and thus there is an unknown risk of accelerated articular wear necessitating longer term study. Cite this article: Bone Joint J 2016;98-B:1175–9

We have studied the long-term results of core decompression as the sole treatment for Ficat stages I, II and III ischaemic necrosis of 128 femoral heads in 90 patients. The 5-, 10- and 15-year survival rates for the three stages were respectively: stage I 100%, 96% and 90%; stage II 85%, 74% and 66%; and stage III 58%, 35% and 23%. At a mean follow-up of 11 years (4.5 to 19), 55 hips had failed (43%). No further surgery had been needed for 88% of stage-I, 72% of stage-II and 26% of stage-III hips; but despite the generally satisfactory clinical results, 56% of the hips had progressed radiographically by at least one Ficat stage. Complications of the core procedure included four fractures, all from postoperative falls, and one head perforation due to technical error. We conclude that core decompression delays the need for total hip replacement in young patients with ischaemic necrosis

Bone-marrow oedema syndrome (BMOS) of the hip gives a characteristic MRI pattern, in association with severe pain, non-specific focal loss of radiological density and a positive bone scan. In our MRI-controlled study, nine patients with non-traumatic BMOS in ten hips all had core decompression. Bone-marrow pressure measurements and intraosseous venography in five cases showed pathological values. All patients had immediate relief of pain, with return of MRI signals to normal after three months. Regular review was continued for at least 24 months with serial clinical radiological and MRI assessment. At a mean follow-up of 33 months all patients remained free of pain with normal radiographs and MR scans. The histological evaluation of undecalcified sections obtained from eight core decompressions confirmed the presence of bone-marrow oedema, with necrotic and reparative processes involving bone and marrow similar to those of early avascular necrosis but with no evidence of 'osteoporosis'. These findings support the assumption that BMOS may be the initial phase of non-traumatic avascular necrosis. In most patients BMOS will have a self-limiting course, but the duration of symptoms may be reduced by core decompression treatment

We have reviewed 54 hips in 46 patients from 2 to 14 years after a joint-preserving operation for idiopathic avascular necrosis of the femoral head. The choice between core decompression (17 hips), bone grafting (18), rotation osteotomy (15) or varus osteotomy (4) was determined by the stage and location of the area of necrosis. The overall success rate was unexpectedly low at 60%. Core decompression and bone grafting by our techniques gave poor long-term results, but those of rotation or varus osteotomies, performed with care for the correct indications, were better. The indications for each procedure are discussed: osteotomy is best when the area of necrosis is shallow and localised in the medial or anterior portion of the femoral head

From 1974 to 1981, we performed 28 core decompressions of the distal femur for pathologically confirmed avascular necrosis. At a mean follow-up of 54 months (range 20 to 140 months) and using the Ficat stages, all seven cases in stage I and stage II had good results. Of 21 cases in stage III, 11 cases had good results, four had poor results, and six needed total knee replacement. There were no significant orthopaedic complications. The procedure is worthwhile and will be more accurate with new methods of imaging

We performed a randomised trial on 37 hips (33 patients) with early-stage osteonecrosis (ON). After the initial clinical evaluation, including plain radiography and MRI, 18 hips were randomly assigned to a core-decompression group and 19 to a conservatively-treated group. All the patients were regularly followed up by clinical evaluation, plain radiography and MRI at intervals of three months. Hip pain was relieved in nine out of ten initially symptomatic hips in the core-decompression group but persisted in three out of four initially painful hips in the conservatively-treated group at the second assessment (p < 0.05). At a minimum follow-up of 24 months, 14 of the 18 core-decompressed hips (78%) and 15 of the 19 non-operated hips (79%) developed collapse of the femoral head. By survival analysis, there was no significant difference in the time to collapse between the two groups (log-rank test p = 0.79). Core decompression may be effective tin symptomatic relief, but is of no greater value than conservative management in preventing collapse in early osteonecrosis of the femoral head

Avascular necrosis (AVN) is a serious complication of high-dose chemotherapy for haematological malignancy in childhood. In order to describe its incidence and main risk factors and to evaluate the current treatment options, we reviewed 105 children with a mean age of 8.25 years (1 to 17.8) who had acute lymphoblastic or acute myeloid leukaemia, or a non-Hodgkin’s lymphoma. Overall, eight children (7.6%) developed AVN after a mean of 16.8 months (8 to 49). There were four boys and four girls with a mean age of 14.4 years (9.8 to 16.8) and a total of 18 involved sites, 12 of which were in the femoral head. All these children were aged > nine years (p < 0.001). All had received steroid treatment with a mean cumulative dose of prednisone of 5967 mg (4425 to 9599) compared with a mean of 3943 mg (0 to 18 585) for patients without AVN (p = 0.005). No difference existed between genders and no thrombophilic disorders were identified. Their initial treatment included 11 core decompressions and two bipolar hip replacements. Later, two salvage osteotomies were done and three patients (four hips) eventually needed a total joint replacement. We conclude that AVN mostly affects the weight-bearing epiphyses. Its risk increases with age and higher steroid doses. These high-risk patients may benefit from early screening for AVN.

Cite this article: Bone Joint J 2013;95-B:1708–13.

Introduction and Objective. Osteoarthritis of the knee joint is common in old age population in every part of world. Pain is the major source of disability in patients with osteoarthritis of the knee joint. Subchondral bone marrow is richly innervated with nociceptive pain fibers and may be a source of pain in patients with symptomatic degenerative joint disease. Current therapy for managing bone marrow oedema is core decompression (CD), combining core decompression and injection of hydroxyapatite cement or autologus chondrocyte supplementtion. But all of this work has been done in femoral head and authors documented good result with minimal complication. There are various studies in literature suggesting treatment to repair BME by restoring support and relieving abnormal stresses with accepted internal fixation and bone stimulating surgical techniques in relieving knee OA pain. In this study, we present efficacy of knee arthroscopy with adjunctive core decompression and supplementation with structural scaffold to improve self-rated visual analog scale (VAS) pain scores, rate of conversion to arthroplasty, and patient satisfaction levels. Materials and Methods. The study included patients aged between 40 and 75 years old, with pain in the knee for at least six months, associated with high-signal MRI lesion on T2 sequences, on the tibia or femur. Trephine was used as the bone decompression instrument. Trephine has a diameter of 8–10 mm and operation with trephine requires that a cortical incision window be made prior to decompression treatment, thus necessitating strict disinfection. This procedure was done under spinal anesthesia. After diagnostic arthroscopy, decompression was done under C –ARM in desired area on MRI. After decompression, defect was filled with Poly ester urea's scaffold impregnated with BMAC. Results. Patients were assessed using the visual analog pain scale and the KOOS score, one week before surgery and one, three, six, 12, and 24 weeks after the procedure. MRI images were analyzed Lesions were mapped and measured in the axial, coronal, and sagittal views to plan the injection site and the trajectory of the cannula used for the procedure. Radiographs using anteroposterior, profile, and Rosenberg views of the knee and lower limb were performed to classify the lesion according to the Kellgren-Lawrence classification and to assess lower limb alignment. Evaluation using the KOOS showed a mean total score in the preoperative period of 38.44 points and of 60.7, 59.08, 56.92, 64.40, and 71.36 points at one, three, six, 12, and 24 weeks after surgery, respectively. In the VAS assessment, mean was 7.8 points preoperatively and 2.8, 2.6, 2.5, 1.3, and 0.5 points in the same periods. Conclusions. Hence it can be Concluded that this new innovative technique has provided significant improvements in the parameters of pain and functional capacity in the short-term assessment

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

Introduction. Without intervention 80% of hips with osteonecrosis (ON) will progress. Core decompression has shown favorable results (60–80% survivorship) in early stage ON, and recently, bone marrow aspirate concentration (BMAC) injection into the decompressed femoral head has been proposed to stimulate healing of the necrotic lesion and improve outcomes and survivorship. Methods. We retrospectively reviewed the clinical and radiographic outcomes of 42 hips in 26 patients who underwent core decompression with BMAC for ON with a minimum of 1 year follow up. We evaluated pre-op visual analog pain scores (VAS), Steinberg class based on radiographs, as well as Kerboul angle as measured on MRI. Clinical outcomes were reported as change in VAS at final follow up, advancement in Steinberg classification based on radiographs at final follow up, or decision to proceed with THA. Results. At final follow up, VAS scores had improved from 7 to 2.6 (P<0.05). A total of 33 of 42 hips (78.5%) had stable radiographs without collapse or progression to a higher Steinberg class, while a total of 9 of 42 hips (21.4%) went on to THA. Of the patients that went on to THA, all had a pre-operative Steinberg classification of 2C or higher, and the pre-op Kerboul angle in this cohort was 243, compared to 171 in the group that did not go on to THA (p<0.05). In patients with pre-op Steinberg class 2B or less, there was no advancement in radiographic grade, whereas 61% of patients with pre-op Steinberg grade 2C or higher progressed on to a more advanced stage. Conclusion. Core decompression with BMAC significantly improves clinical symptoms and helps prevent the advancement of ON when performed on patients in whom ON is classified as Steinberg class 2B or less, or in whom the Kerboul angle is 180 or less. For any tables or figures, please contact the authors directly

Osteonecrosis of the femoral head (ONFH) is a debilitating, painful, progressive, and refractory disease that has multiple etiologic risk factors. It is caused by bone cell death, which itself has various causes, leading to femoral head collapse and subsequent osteoarthritis. ONFH primarily influences patients aged from 20 to 50 years; in addition, bilateral hip joints are involved in 75% of patients. Causes include use of corticosteroids, alcohol abuse, previous trauma, hemoglobinopathy, Gaucher disease, coagulopathies, and other diseases. No pharmacologic treatment has been shown to be effective for early ONFH. Outcomes of total hip arthroplasty (THA) for these young and active patients have some drawbacks, primarily due to the young age of these patients, limited lifetime and durability of the implants and their fixation, and the skeletal manifestations of osteonecrosis. As a result of these concerns, there has been an increased focus on early interventions for ONFH aimed at preservation of the native articulation. Core decompression is currently the most widely accepted surgical treatment at the early stage of avascular osteonecrosis (AVN); however, due to limited efficacy, its use has been debated. There is currently no standardised protocol for evaluating and treating osteonecrosis of the femoral head in adults in the United States. Although total hip replacement is the most frequent intervention for treatment of post-collapse (Steinberg stage-IIIB, IVB, V, and VI) osteonecrosis; core decompression is the most commonly offered intervention for symptomatic, pre-collapse (Steinberg stage-IB and IIB) osteonecrosis. Less frequently offered treatments include non-operative, pharmacologic or modality management, osteotomy, vascularised and non-vascularised bone-grafting, hemiarthroplasty, resurfacing and arthrodesis. A promising, minimally invasive, core decompression procedure combined with a mesenchymal stem cell grafting technique which restores vascularity and heals osteonecrotic lesions has become popularised. This procedure is called a bone marrow aspirate concentrate (BMAC) procedure. During a BMAC, mesenchymal stem cells (in the form of concentrated iliac crest bone marrow) are injected through a core decompression tract into the area of necrosis in the femoral head. Most patients with early (pre-collapse) disease have excellent results at 2 to 5 years of clinical follow-up. Patients are weight bearing as tolerated on crutches after the procedure for 6 weeks, and are able to go home on the same day or next day after surgery with minimal pain. We can report on the early, promising results of 300 patients with ONFH treated with BMAC in the United States by two expert hip surgeons with at least 75%-80% survivorship. The care of adults with osteonecrosis of the femoral head is highly variable. This paper will discuss the various non-operative and operative treatment algorithms for ONFH available today. We will also report on a promising, new technique (BMAC), which improves the efficacy of traditional core decompression for early ONFH. The goal of treatment of early ONFH is to avoid THA in young, active patients and this talk will discuss those interventions and treatments which help accomplish that goal

Introduction. The purpose of this study was to analyze trends in the surgical management of ON in recent years. Specifically, we evaluated the annual prevalences of: 1) joint preserving procedures (osteotomies and core decompression/grafts) and 2) joint non-preserving procedures (total hip arthroplasties [THAs], revision THAs, partial THAs) for the treatment of osteonecrosis of the femoral head (ONFH) between 2009 and 2016. Background. A total of 406,239 ONFH patients who were treated between 2009 and 2016 were identified from a nationwide database. Treatment procedures were extracted using ICD-9-CM and ICD-10-CM procedure codes. Annual rates of each of the above procedures were calculated and the trends in the procedure types were also evaluated. Chi-square tests were performed to compare the annual prevalence of each procedure. The mean annual prevalence over the 8-year study period was calculated for each procedure. Results. Throughout the study period, the number of joint preserving procedures steadily increased by 27%. In the earliest year studied, 2009, 41% (n=19,559) of the total procedures for ONFH were joint-preserving compared to 52% (n=13,715) in 2016. The rates of joint non-preserving procedures decreased (59 to 48%) over the same period (Figure 1). There was a decreasing annual prevalence of THAs (88 to 82%), revision THAs (2.0 to 1.4%), partial THAs (3.4 to 2.3%), osteotomies (4.2 to 3.2%), and core decompression (1.9 to 1.4%) throughout the study period (p<0.001). Throughout the 8-year period, THA was most commonly performed (mean annual prevalence 83%) whereas osteotomies (3.7%), partial THA (2.8%), core decompression/graft (1.9%), and revision THA (1.5%) were less commonly performed. Conclusion. In order to better understand trends in ONFH management, this study evaluated the annual prevalence of 5 commonly performed procedures. Although earlier data indicated decreasing rates of joint preserving procedure, this study found ONFH management has shifted more towards these procedures. For any tables or figures, please contact the authors directly

Introduction. The treatment osteonecrosis of the femoral head remains uncertain. Core decompression is the standard technique for the early stages (ARCO I and II). A new alternative is core decompression combined with the insertion of an osteonecrosis rod. This implant is supposed to reduce the intraosseous pressure and to give additional structural support. The aim of this study was to evaluate the clinical and radiological outcome via magnetic resonance imaging (MRI) of this new technique. Methods. Twenty-three patients were included in this study. All patients underwent a core decompression combined with the insertion of an osteonecrosis rod. Results. A survival rate of 44 % (10 of 23 patients) was found. The conversion to a total hip arthroplasty was performed after a mean interval of 529 days (range, 120 to 1348 days) because of persistence of pain or destruction of the joint. In five cases, a conversion to a long-stem hip arthroplasty, in seven cases to a short-stem arthroplasty, and in one case in an external hospital, to a hip resurfacing was performed. The majority of patients within the surviving group revealed an almost unchanged stage (mean follow-up of 477 days). In two cases, a radiological regression was obvious. A follow-up MRI of one of those patients showed complete regression. Conclusion. The outcome after core decompression combined with the insertion of a tantalum osteonecrosis intervention implant did not show superior results compared to core decompression. This is in contrast to prior studies. In addition, the surgical procedure and rehabilitation was prolonged and the costs higher than for isolated core decompression. An advantage is low risk of fracture post-operatively. In the case of conversion to total hip arthroplasty, no problems appeared during explantation of the tantalum implant

Core decompression is a common treatment for early stage osteonecrosis of the femoral head due to the simplicity of the procedure and the positive results of this intervention. A number of different core decompression methods exist: including methods backfilled by a bone graft material and those without filling. Due to the inherent desire that the core decompression defect regenerate healthy bone, reduce pain, and stave off the need for total hip arthroplasty for some period of time, this surgically created defect is an excellent application for the use of a bone graft substitute. Recently, an injectable calcium sulfate (CaSO. 4. )/calcium phosphate (CaPO. 4. ) composite graft has become available for use in the treatment of surgically created defects. The synthetic graft is an injectable composite of CaSO. 4. , tricalcium phosphate (TCP) granules, and brushite that hardens in situ. The triphasic resorption pattern exhibited by this material in vitro and in pre-clinical canine studies has indicated that the CaSO. 4. matrix resorbs at early time points to reveal a longer resorbing CaPO. 4. scaffold for bone onlay. In a canine proximal humerus model, the use of this material in a critical bone defect has demonstrated a regenerate with higher compressive strength at 13 week time points than defects treated with CaSO. 4. alone, defects treated with autograft, and normal untreated bone. By 26 weeks, the regenerated bone within the defect resembled normal bony architecture with similar mechanical properties. Early clinical series have indicated similar results to the canine studies. Reports of early clinical findings have included a 12 patient benign bone tumor series with 4–12 month follow up and a core decompression series of 38 Ficat stage I–III hips with 6–16 month follow up. Preliminary radiological results in the bone tumor series showed peripheral resorption of the injectable CaSO. 4. /CaPO. 4. composite with new bone formation along the resorbing edge. Clinically, patients in the bone cyst series have not experienced fractures or additional surgery and all patients have displayed full functional recovery. In the core decompression series, 32 of the 38 hips experienced pain relief and within the subset of 30 symptomatic hips, 24 had pain relief. These results, although preliminary, are promising outcomes. Collectively, the pre-clinical and preliminary clinical results indicate that the use of an injectable CaSO. 4. /CaPO. 4. composite could prove to be of benefit in core decompression of the femoral head. The staged resorption and dense bone formation evidenced in canine studies would be desirable in core decompression techniques where healthy bony ingrowth is the goal. Due to the straightforward compilation and use of this composite, the incorporation of this material as a backfill matrix into the core decompression procedure is technically simple. Although additional studies are certainly merited, these early clinical results are encouraging

Introduction: Osteonecrosis of the femoral head is a devastating disease that often progresses to hip joint destruction necessitating total hip arthroplasty. The use of core decompression is typically recommended for patients with early small and medium-sized lesions. The reported efficacy of this procedure has been variable. Recently, various adjustments to the surgical technique have been described. There has been interest in performing multiple drillings under fluoroscopic guidance and combining core decompression with electrical stimulation and/or biological adjunctive growth factors. In order to assess whether the efficacy of this procedure has improved during the last 15 years using modern techniques, we compared recently reported radiographic and clinical success rates to results of surgeries performed prior to 1992. In addition, we evaluated the outcomes of our cohort of 52 patients (79 hips) who were treated with multiple small diameter drillings. Method: A systematic review utilizing the Medline and Embase bibliographic databases found 59 studies meeting our inclusion criteria that were related to core decompression and osteonecrosis. The mean age for patients was 39 years (range, 9 to 83 years), and the mean follow-up was 56 months (range, 1 to 228 months). From these reports, there were 1,429 hips treated prior to 1992 and 1,957 hips since 1992. Other than the smaller percentage of Ficat stage III cases in the later studies, the reported etiologies and the stratification of preoperative Ficat stage were similar in the two strata of groups with the majority of patients being Ficat stage I and II and corticosteroids and alcohol being the most frequently reported associated diagnosis. From our institution, we identified 52 patients (79 hips) who had a core decompression utilizing a multiple small diameter (3 millimeters) technique at mean follow-up of 65 months. The outcome parameters collected for each core decompression patient at our institution and from the reports in literature were the number and percentage of patients who required additional surgeries, were clinical failures, or had radiographic progression of the disease. Results: Overall, the success rates were higher for the studies that reported core decompressions performed during the last 15 years compared to procedures that were done prior to 1992. The proportion of patients surviving without additional surgery increased from 57% (range, 28 to 97%) in the earlier studies to 67% (range, 18 to 100%) in the more recent reports. Similarly, the radiographic success also increased from 54% (range, 0 to 94%) for the pre-1992 cohort to 59% (range, 22 to 90%). While clinical success increased from 57% (range, 28 to 94%) in the pre-1992 procedures to 61% (range, 29 to 90%) in reports from the last 15 years, this improvement was not statistically significant. Stratification by Ficat stage showed that there were significantly fewer patients who were Ficat stage III after 1992 suggesting that patient selection was the primary reason for the improvement in outcomes. For hips classified as Ficat stage II, there was an increase in clinical success and reduced percentage of patients requiring additional surgery in the more recent reports. The results of our cohort of patients were similar to other reports in the last 15 years. Patients who had small lesions and were Ficat stage I prior to treatment had the best results with 79% showing no radiographic progression. Discussion: The results of the present study do not provide adequate evidence to suggest that recent techniques provide better clinical scores or radiographic outcomes. However, the additional accumulation of successful reports in the last decade confirms that core decompression is a safe and effective procedure for the treatment of early stages of osteonecrosis of the femoral head. Furthermore, these results suggest that proper patient selection can improve outcomes for this procedure. Based on the results of our experience as well as that of other studies, we will use core decompression to treat patients who have early small and medium-sized lesions and are Ficat stage I or II. Additionally, the mid-term follow-up of the multiple small diameter core decompression patients at our institution was longer than most studies, and had a success rate similar to, or higher than other reports, which confirms the use of this technique as the authors’ preferred method

Introduction: Osteonecrosis is a devastating disease which can affect multiple joints including the distal radius. Although there are a number of studies that have reported the clinical outcomes of patients treated for osteonecrosis of the hip, knee, shoulder, and other locations, there are no known studies that have evaluated the outcome of patients who have this disease in the distal radius. The purpose of this study was to assess the characteristics of atraumatic, symptomatic osteonecrosis of the distal radius. In addition, based on reports that have shown the safe and effective use of core decompressions to treat early stages of osteonecrosis in other joints, we assessed whether this treatment modality also would provide pain relief and delay progression of the disease in the distal radius. Methods: A review of 434 osteonecrosis patient records from the past 7 years in our prospectively collected database identified 4 patients (6 wrists) who had the disease in the distal radius. Two of these patients also had the disease in the ulna. All 4 patients were women, and their mean age was 46 years (range, 37 to 52 years). Clinical and radiographic outcomes were assessed at a mean of 39 months (range, 12 to 84) following treatment with core decompression. The clinical evaluations were conducted using the Michigan Hand Outcomes Questionnaire (MHQ). The reported pre-operative MHQ component scores for function, completion of everyday activities, pain, completion of work activities, overall appearance of the hands, and patient satisfaction were compared to the results of the MHQ at final follow-up. Radiographic success of the core decompressions was based on whether there was any progression in the stage of the disease. Results: The most common risk factor for this cohort of patients was corticosteroids with 3 of the 4 patients having reported prior use. Other risk factors included alcohol consumption on a regular basis (n = 2), tobacco abuse (n = 2), blood dyscrasia (n = 2), and systemic lupus erythematosus (n = 1). Additionally, all 4 patients had multifocal osteonecrosis (affecting at least four separate anatomic sites. Overall, the patients reported a mean improvement in MHQ score (from 65% to 84%). Stratified by category, satisfaction improved from 64% to 88%, overall hand function increased from 64% to 81%, and pain was reduced from 60% to 25%, for pre- and post-operative values, respectively. One patient (2 wrists) required additional core decompressions in each wrist at one year following surgery but reported sustained improvement in her MHQ for both wrists at two years following her second core decompressions. There were no complications associated with the core decompressions, and there was no radiographic progression in the stage of the disease in any of the cases. Discussion: Osteonecrosis of the distal radius is rarely found in patients with this disease (< 1%). It can be found in patients with osteonecrosis of other joints who have a symptomatic wrist and may have more than one risk factor. It can be readily diagnosed with x-rays and/or MRI. The results of the present study suggest that core decompression is a safe and effective treatment modality for symptomatic osteonecrosis of the wrist at the distal radius and/or ulna. Although the level of improvement in MHQ varied for each case, all patients reported reduced pain and improved function at final follow-up without any apparent complications. Based on these results, we recommend the use of core decompressions to alleviate the symptoms and to possibly delay the progression of distal radius osteonecrosis

Introduction. Collapse of femoral head associated with end-stage arthritis form hallmark of osteonecrosis of femoral head. Purpose was to assess efficacy of platelet rich plasma following core decompression in early stage of osteonecrosis of femoral head. Methods. Forty consecutive age, sex and BMI-matched patients of osteonecrosis were enrolled for this prospective randomized comparative double blinded clinical study. 19 patients belonged to intervention group (PRP with Core decompression) and 21 to control (Core decompression) group. 8ml of autologous PRP was injected into channels alongwith Calcium Chloride (4:1) after core decompression. Patients were assessed for outcome measures by pain score, functional and Harris Hip scores, Modified Kerboul angle (combined necrotic angle) in MRI. Patients were followed up after 6, 24 weeks and final follow up (mean 10.33 months). Results. There was statistically significant difference in pain score in two groups at different follow ups (p: 0.002, 0.00; 0.001). The difference in function scores in two groups was statistically significant (p: 0.001). There was statistically significant difference in Harris Hip score in two groups at different follow ups (p: 0.021, 0.001; 0.003). Mean increase in modified Kerboul angle in group A was 11.32 (SD±13.00) and in group it was 18.33 (±14.347). 6 (24%) hips in group A and 12 (42%) hips in group B had progression of disease upto final follow up. Conclusions. Core decompression augmented with platelet rich plasma is effective in providing pain relief, improving the functional status and delaying or cessation of progression in early stage of osteonecrosis of hip

Introduction. What is the most effective treatment of the early stages for osteonecrosis of the femoral head? Since the results of several treatment modalities such as multiple drilling, core decompression with or without bone graft, and vascularized fibular grafts have not been completely successful, we tried multiple drilling and stem cell transplantation to treat the early stages of osteonecrosis of the femoral head and to minimize patient morbidity. We report the clinical and radiological results of stem cell transplantation and core decompression. Methods. One hundred and twenty-eight patients (190 hips) who had undergone surgery were divided in two groups based upon which treatment they had received: (1) multiple drilling and stem cell transplantation, and (2) core decompression, curettage, and bone graft. The clinical and radiological results of the two groups were compared. We defined failure as the need for additional surgery, or a Harris hip score of less than 75 points. Results. After a minimum 5-year follow-up in the stem cell transplantation group, 64.3% (27/42) of hips with Stage IIa disease, 56.7% (21/37) of hips with Stage IIb disease, and 46.9% (23/49) of hips with Stage III disease had no additional surgery. In the conventional core decompression group, 66.7% (6/9) of hips with Stage IIa disease, 66.7% (6/9) of hips with Stage IIb disease, and 60% (3/5) of hips with Stage III disease had no additional surgery. Survival rates of patients with Ficat Stages I or II lesions were greater than survival rates for patients with Stage III lesions. There was no difference of survival rate between the two groups. Conclusion. When comparing the clinical and radiological results of the two methods, we found that there was no significant difference between the two groups. The same results were found between stem cell transplantation and the conventional method of core decompression

This retrospective study describes the long-term results of core decompression and placement of a non-vascularised bone graft in the management of avascular necrosis of the femoral head. We treated 80 hips in 65 patients, 18 by a cortical tibial autograft and 62 by a fibular allograft. The mean age of the patients was 36 years (. sd. 13.2). A total of 78 hips were available for evaluation of which pre-operatively six were Ficat-Arlet stage 0, three stage I, 31 stage IIA, 16 stage IIB, 13 stage III and nine stage IV. A total of 34 hips (44%) were revised at a mean of four years (. sd. 3.8). Survivorship analysis using a clinical end-point showed a survival rate of 59% five years after surgery. We found a significant difference (p = 0.002) in survivorship, when using a clinical and radiological end-point, between the two grafts, in favour of the tibial autograft. We considered this difference to be the result of the better quality and increased volume of tibial bone compared with that from the trochanteric region used with the fibular allograft. This is a relatively simple, extra-articular and reproducible procedure. In our view core decompression, removal of the necrotic tissue and packing of the cancellous grafts into the core track are vital parts of the procedure

Aims. Earlier studies dealing with trends in the management of osteonecrosis of the femoral head (ONFH) identified an increasing rate of total hip arthroplasties (THAs) and a decreasing rate of joint-preserving procedures between 1992 and 2008. In an effort to assess new trends in the management of this condition, this study evaluated the annual trends of joint-preserving versus arthroplasties for patients aged < or > 50 years old, and the incidence of specific operative management techniques. Methods. A total of 219,371 patients with ONFH were identified from a nationwide database between 1 January 2009 and 31 December 2015. The mean age was 54 years (18 to 90) and 105,298 (48%) were female. The diagnosis was made using International Classification of Disease, Ninth revision, Clinical Modification (ICD-9-CM) and Tenth Revision, Clinical Modification (ICD-10-CM) procedure codes. The percentage of patients managed using each procedure during each year was calculated and compared between years. The trends in the use of the types of procedure were also evaluated. Results. The rate of joint-preserving procedures was significantly higher in patients aged < 50 years compared with those aged > 50 years (4.93% vs 1.52%; p < 0.001). For the overall cohort, rates of arthroplasty were far greater than those for joint-preserving procedures. THA was the most commonly performed procedure (291,114; 94.03%), while osteotomy (3,598; 1.16%), partial arthroplasty (9,171; 2.96%), core decompression (1,200; 0.39%), and bone graft (3,026; 0.98%) were performed markedly less frequently. The annual percentage of patients managed using a THA (93.56% to 89.52%; p < 0.001), resurfacing (1.22% to 0.19%; p < 0.001), and osteotomy (1.31% to 1.05%; p < 0.001) also decreased during the study period. Conclusion. We found that patients with ONFH have been most commonly managed with non-joint-preserving procedures. Our findings provide valuable insight into the current management of this condition and should increase efforts being made to save the hip joint. Cite this article: Bone Joint J 2020;102-B(7 Supple B):122–128

Post-traumatic osteonecrosis of the femoral head (ONFH) is a major complication of femoral neck fractures that require numerous solutions. The purpose of the current study is to investigate the effects of platelet-rich plasma (PRP) incorporated autologous granular bones graft for the treatment of pre-collapse stages (ARCO stage II-III) of post-traumatic ONFH. A total of 46 patients were eligible and enrolled into the study. 24 patients were treated with core decompression and PRP incorporated autologous granular bones graft (treatment group: 9 females and 15 males, age range, 16–39 years), and 22 patients with core decompression and autologous granular bones graft (control group: 6 females and 16 males, age range, 18–42 years. During a minimum duration of follow-up of 36 months, multiple imaging techniques including X-ray and computed tomography (CT) scanning were used to evaluate the radiological results, and Harris hip score (HHS) and the visual analogue scale (VAS) were chosen to assess the clinical results. Both treatment group and control group had a significant improved HHS (P < 0.001). The minimum clinically important difference (MCID) for HHS was reached in 91.7% of treatment group and 68.2% of control group (P = 0.0449). HHS in treatment group was significantly higher than control group at the last follow-up (P = 0.0254). VAS score was significantly declined in treatment group when compared with control group (P = 0.0125). Successful clinical results were achieved in 21 of 24 patients (87.5%) in treatment group compared with 13 of 22 patients (59.1%) in control group (P = 0.0284). Successful radiological results were achieved in 19 of 24 patients (79.2%) in treatment group compared with 11 of 22 patients (50%) in control group (P = 0.0380). The survival rates using requirement for further hip surgery as an endpoint were higher in treatment group in comparison to control group (P = 0.0260). The PRP incorporated autologous granular bones graft is a safe and effective procedure for the treatment of pre-collapse stages (ARCO stage II-III) of post-traumatic ONFH

Introduction: Osteoneocrosis of the femoral head (ONFH) is difficult to treat as collapse frequently occurs after core decompression. This may be due to the failure to provide structural support during revascularization and healing after core decompression. Cement (PMMA) packing for giant cell tumors of bone has been shown to provide adequate support of the subchondral bone. This study was undertaken to determine whether or not the addition of PMMA packing provides any benefit to the outcome of core decompression for ONFH. Secondary objectives were to assess various factors for prognostic significance. Materials and Methods: A prospective, randomized trial of core decompression ± cement (PMMA) packing for ARCO stage I or II ONFH was conducted. Outcome measures were: radiographic (XR) progression, conversion to hip arthroplasty (THA), WOMAC, SF 36, and Harris Hip scores (HHS). Survivorship analysis using Kaplan-Meier estimates was performed. Results: The time to XR progression at 3 years for the core vs. core + PMMA cohorts was 42 ± 11 mo vs. 45 ± 12 mo, p=0.68, respectively. The time to THA at 3 yrs for the core vs. core± PMMA groups was 42 ± 11 mo vs. 67 ± 12 mo, p=0.17, respectively. Comparing pre vs.1 year postoperative WOMAC scores, for the core + PMMA group, there were statistically significant improvements in pain (p=0.082), stiffness (p=0.03), physical function (p= 0.05) and total score (p=0.03) whereas for the core decompression group, there was no significant difference noted among the same domains (p=0.06, 0.25, 0.74, 0.88) respectively. The SF 36 role physical domain score was higher for the core + PMMA group at 1 year (p=0.07) and 15 mos (p=0.09) but was no different at 3 yrs (p=85). For the physical function and bodily physical domains, there was no difference at any time point. The factors of smoking (y/n) p=0.003, location (central/ medial/lateral) p=0.03, per cent femoral head involvement (< 15, 15–30, > 30%) p=0.05, age (< 40, ≥40 yrs), and necrotic arc (< 40, ≥40) p=0.005, were significant predictors for XR progression on univariate analysis but upon Cox multivariate regression, only age (p=0.09), smoking (p=0.07), and necrotic arc (p=0.04) remained independently, statistically significant. Discussion: The addition of PMMA packing to core decompression for pre-collapse ONFH (ARCO I/II) does not improve the outcome of treatment as measured by XR progression and conversion to THA. There is a benefit to PMMA packing for pain relief at 12–15 mos. as measured by the mean WOMAC, HHS and SF 36/role physical scores but this benefit ceases at 3 years after treatment. Age ≥40 years, smoking, and necrotic arc ≥40 are all predictive of eventual progression of disease on XR

Introduction: The purpose of this study was to compare the results of the efficacy of two decompressive methods (multiple drilling vs standard core decompression) for the treatment of precollapse osteonecrosis of the femoral head. Methods: The results in a consecutive series of 54 patients (65 hips) who had undergone multiple drilling (31 patients, 35 hips) or core decompression (23 patients, 30 hips) for the treatment of precollapse osteonecrosis of the femoral head between September 1991 and July 2001 were reviewed. The average duration of follow up was 60.3 months (range, 24–103 months) in the multiple drilling group and 44.8 months (range, 24 to 84 months) in the core decompression group. The presence of collapse and radiographic progression in each group was evaluated prospectively with collapse of the femoral head defined as a failure. Harris hip scores (HHS) were used to evaluate clinical status preoperatively and at the most recent follow up. Results: Radiographically and clinically, high failure was significantly related to the larger size and laterally located lesion (LHI of less than 12%, Urbaniak IIC, Ohzono IC and Kerboul index of more than 240 degrees) in both groups. The average preoperative and the last HHS was 86.7 to 73.7 in the core decompression group and 87.0 to 74.6 in the multiple drilling group. Compared to the core decompression group, the multiple drilling group had significantly longer times before collapse (mean 42.3 months vs 22.6 months, p=0.011) and a lower rate of collapse within 3 years after operation (55.0% vs 85.7%, p=0.03). Discussion: Decompressive methods have worse outcomes in case of lesions of larger size and lateral location, even in precollapse stage. Multiple drilling has significantly longer time before collapse and a lower rate of collapse within 3 years after operation than standard core decompression

Management of symptomatic osteonecrosis of the hip includes either some type of head preservation procedure or a total hip arthroplasty (THA). In general, once there is collapse of the femoral head, femoral head preservation procedures have limited success. There are a number of different femoral head preservation procedures that are presently performed and there is no consensus regarding which one is most effective. These procedures involve a core decompression with some type of vascularised or nonvascularised grafting of the femoral head. Core decompression with bone grafting of the femoral head with stem cells harvested from the iliac crest and vascularised fibula grafts are the two most popular femoral head preservation procedures. Once the femoral head has collapsed then a THA should be performed when the patient has significant disability. In the past, total hip arthroplasty in osteonecrosis patients was not considered a highly successful procedure because it was performed in younger patients (most patients are younger than fifty years of age) and longevity was limited by wear and osteolysis. The advent of reliable cementless acetabular and femoral fixation and alternative bearing surfaces (i.e. highly crosslinked polyethylene liners) has been associated with improved outcomes and enhanced longevity. THA is considered the procedure of choice even for young patients (less than 30 years old) with collapse of the femoral head and significant pain and disability

Purpose: Spontaneous osteonecrosis of the knee is a potentially greatly debilitating condition. While success has been reported with non-operative treatment of this disorder in its earliest stages, knee arthroplasty is the only viable modality if allowed to progress to condylar collapse. The purpose of this report is to review the etiologic and pathophysiologic principles of spontaneous osteonecrosis of the knee, to present our experience with joint-preserving surgical treatment of this condition, and finally to introduce a treatment algorithm developed based on this knowledge. Method: Seventeen patients with a clinical and/or radiographic a diagnosis of spontaneous osteonecrosis of the knee, and exclusion of secondary osteonecrosis, who failed non-operative modalities were treated with joint-preserving surgery at a single center between January 2000 and December 2006. Treatment modalities included arthroscopy, and either percutaneous core decompression and/or osteochondral autograft transfer. Three knees were lost to follow-up, leaving 14 knees with a mean follow-up of 37 months (range, 11 to 84 months). Results: Twelve of 14 knees (86%) had knee joint survival with a mean Knee Society Score of 80 points (range, 45 to 100 points) at final follow-up. One patient was treated with serial core decompression followed by osteochondral transfer, and was included in both groups. Six of 7 patients (86%) treated with core decompression alone had a successful clinical outcome, as did 7 of 8 patients (87%) treated with osteochondral autograft transfers. Two patients (14%) progressed to condylar collapse, and were treated with total knee arthroplasty with successful results. Conclusion: Based on these results, we propose a treatment algorithm that begins with non-operative treatment, followed by joint-preserving surgery consisting of arthroscopy, core decompression, and/or osteochondral autograft transfer. Although our sample size is small, the results suggest that this proposed treatment algorithm can successfully postpone the need for knee arthroplasty in selected patients with pre-collapse spontaneous osteonecrosis of the knee

We reviewed 11 patients (17 ankles) who had had core decompression for symptomatic avascular necrosis of the talus before collapse. The Mazur grading system was used to assess function preoperatively and at final follow-up, and radiographs were graded according to the Ficat and Arlet (1980) classification modified for the ankle. At a mean follow-up of seven years (2 to 14) 14 ankles (82%) had an excellent or good outcome (Mazur scores > 80 points; pain scores > 40 points (41 to 50)). The other three ankles required tibiotalar fusion at a mean of 13 months (5 to 20) after core decompression. We conclude that core decompression is a viable method of treatment for symptomatic avascular necrosis of the talus before collapse

Introduction: Osteonecrosis of the knee occurs with approximately 10% of the incidence of osteonecrosis of the hip. Core decompression is a minimally invasive technique which can potentially forestall bony collapse and thus avoid the need for joint arthroplasty. The purpose of this study was to evaluate the efficacy of a new minimally invasive approach using a small diameter Steinman pin to perform core decompression of the knee. Materials and Methods: Between September 5, 2000 and May 30, 2003, the senior author performed 55 core decompressions of the knee in 39 patients with symptomatic osteonecrosis of the knee. All procedures were performed using the small-bit drilling technique. There were 32 women and 7 men who had a mean age of 43 years (range, 18 to 52 years). Radiographic and clinical outcomes were assessed during post-operative clinical visits, with persistent pain, loss of joint space, or progression to total knee replacement considered failures. Results: There were excellent or good outcomes in 45 knees (82%) at a mean three year follow-up (range, 2 to 5 years). Four patients had symptomatic knees that led to total knee arthroplasty. There were no complications from the procedures which were all performed as out-patient surgery. Discussion: The percutaneous drilling technique appears to be a low-morbidity method of relieving symptoms in patients with symptomatic knees from osteonecrosis. These short-term results are encouraging for this difficult to treat disease

Introduction: It is desirable to delay or avoid total joint replacement in young patients who have osteonecrosis of femoral head. There are some head preserving surgical procedures that attempt this including osteotomy, core decompression, and bone grafting. The vascularized fibular graft has been reported to be a reliable procedure, but unfortunately it has donor site morbidity and is considered technically demanding. Therefore, materials have been developed to substitute for structural fibular graft. New trabecular metal has been developed to be used for osteonecrosis of femoral head. The purpose of this study was to review the clinical outcomes of trabecular metal as a treatment intervention method for osteonecrosis of the femoral head. Materials and Methods: Seven patients (8 hips) with osteonecrosis of femoral head received core decompression and a trabecular metal implant, beginning in March 2003. The stage of osteonecrosis was I or II according to Ficat and Arlet except for one case (stage III). The procedure consists of a core decompression and insertion of trabecular metal rod (porous tantalum, Zimmer Inc./ Implex Incorporation). A Harris Hip Score was obtained pre-operatively, and at three and at three and six months. Radiographic data was collected at the same time of clinical follow-up. Results: All 7 patients are doing well. Radiographic review shows no evidence of further femoral head collapse. Discussion: Even though this is short term follow-up, the authors propose that the use of trabecular metal in osteonecrosis patients is simple, safe, and effective for the salvage of the hip

Introduction: Avascular Necrosis (AVN) of the femoral head is a complex disease that often leads to disabling hip pain and degenerative arthritis. Core decompression is currently the most common procedure used to treat the early stages of AVN but used alone may not provide adequate structural support. Trabecular metal may be a promising development by providing the support needed after a core decompression while minimizing the surgical complications of bone grafts. The important stiffness is similar to a fibular graft and the implant enables vascular healing via its porosity. This is a small series of patients who underwent this procedure which is minimally invasive. All patients had a non-traumatic aetiology for the AVN and were referred from a Rheumatology clinic closely linked to the orthopaedic clinic. Methodology: This is a retrospective review of consecutive patients who underwent core decompression and insertion of trabecular metal (tantalum) screw for AVN of the femoral head. Preoperatively the severity of the AVN was assessed with the help of a radiologist using a modified Ficat classification (Steinberg 1986) with magnetic resonance imaging. Postoperatively the progression was assessed with x-rays. Results: A total of nine trabecular screws were inserted into five patients with four receiving bilateral operations. Medium age was forty-five years (range 32–57) and 60% males (n=3). Steroids were thought to be the predisposing factor for AVN in all cases. Preoperative MRI studies showed Grade II disease in four hips (44.4%) Grade III in four hips (44.4%) and Grade IV disease in one hip (11.2%) Median follow up time was 14.4 months range (3–27 months). The hip with Grade IV disease went onto develop destruction of the joint and required a total hip replacement fifteen months later. This was a straightforward procedure with easy removal of the implant. The remaining hips have not required revision to date. There have been no implant failures, migration or loosening. This procedure may prove to be a clinically viable implant option for AVN and the study is ongoing. A major problem is the difficulty in seeing patients early enough with early stage disease. (stage 0, stage I and II.) There have been no implant failures migration or loosening to date

Introduction: Osteonecrosis (ON) of the femoral head is a disorder that can lead to femoral head collapse and subsequent total hip replacement. Core decompression is the most widely prescribed treatment for early stage ON but its efficacy is still controversial. Since ON might also be a disease of mesenchymal cells or bone cells, the possibility has been raised that bone marrow containing osteogenic precursors could be implanted into the necrotic lesion. The 2 year results of this controlled double blind pilot study of the effect of autologous bone marrow-mononuclear cell implantation into the necrotic lesion of the femoral head were encouraging but needed to be confirmed by long term follow-up. Methods: We studied 19 patients suffering from stage 1 or 2 ON of the femoral head. Within this group, 24 individual hips were allocated to a program of either core decompression (control group) or to core decompression plus autologous bone marrow mononuclear cells implantation (bone marrow graft group). The treatment group was blinded to both patients and assessors. Primary outcomes sought were safety and feasibility. Feasibility of treatment was defined as; reduction in pain, improvement in joint symptoms, and a reduction in the progression of the ON from stage 1or 2 to subchondral fracture (stage 3). Results: After 60 months, there was a significant reduction in pain, measured on a visual analog scale within the bone marrow graft group. There was also a significant reduction in joint symptoms measured by the Lequesne index and the WOMAC score over the same period. Bone marrow implantation reduced the number of hips monitored in this study that progressed to subchondral fracture (stage 3). In the bone marrow grafted group, 10 of the 13 hips remained at the stage 2 but only 3 of the 11 hips in the control group remained stable. Survival analysis showed a significant difference in the time to collapse between the two groups. At 60 months, 3 of the 11 hips in the control group needed total hip replacement whereas only 2 of the 13 hips in the bone marrow graft group underwent prosthetic replacement. Discussion: Long term results confirmed that autologous bone marrow-mononuclear cells implantation into the necrotic lesion could be an effective treatment of osteonecrosis of the femoral head

Aims: Avascular necrosis of the femoral head (AVN) evolves in destruction of the hip joint. Treatment of this disease is controversial. Early stages are treated with core decompression whilst in later stages þbular grafting, rotational osteotomy or THR are recommended. Purpose of this study is the evaluation of a new combined approach. Methods: We present a series of 147 AVN in 108 patients treated with the combination of core decompression, bone grafting and electrical stimulation. All surgery were performed with a minimal invasive technique and a dedicated set of instruments which allow for accurate and complete removal of the necrotic bone. In 30 cases the disease was in Steinberg stage I, 58 stage II, 42 stage III and 17 stage IV. All patients were kept non weight bearing for 6 weeks and partial weight bearing for further 6 to 8 weeks. PEMF were used for 8 ours daily for 3 months. Average follow-up was 37 months (min 12 months, max 108). Both clinical and radiological results were evaluated. Results: We had a good radiographic result in 96% of cases in stage I, 85% stage II, 45% stage III and 27% stage IV. Clinically, we obtained good results in 87% stage I, in 81% stage II, in 65% stage III and in 48% stage IV. Clinical failure was deþned as the performance of a subsequent operation. None of the patients in stage I or II required further surgical treatment. Nine cases in stage III and 5 in stage IV required THR after an average of 19 months. Conclusions: Core decompression with bone grafting and electrical stimulation is a safe and effective procedure in Stage I and Stage II AVN. Promising results were obtained also in stage III and Stage IV

To evaluate the effectiveness of core decompression using the tantalum trabecular metal system for treatment of an early stage osteonecrosis of femoral head in minimum 1 year to maximum 5 years follow-up. From January 2003 to August 2007, 36 patients in 46 cases underwent core decompression using the tantalum trabecular metal system. The ARCO classification system was used. Retrospective analysis was done. The conversion to total hip arthroplasty due to aggravating hip pain was defined as a clinical failure. With the higher stage of ARCO classification and more lateral location of lesion, the conversions to total hip arthroplasty would be increased. The better outcome was noted with lower stage of ARCO classification and more medial location of the lesion. The higher stage of ARCO classification and more lateral position of lesion, the failure rate of the tantalum trabecular metal system increases. The most important thing is to detect early stage of osteonecrosis of femoral head. The tantalum trabecular metal system is considered as a useful treatment of osteonecrosis of femoral head with lower stage of ARCO classification and medial location of lesion

Introduction. In early stage osteonecrosis of the femoral head (ONFH), core decompression (CD) is often performed; however, approximately 30% of CD cases progress to femoral head collapse. Bone healing can be augmented by preconditioning MSCs (pMSCs) with inflammatory cytokines. Another immunomodulatory approach is the timely resolution of inflammation using cytokines such as IL-4. We investigated the efficacy of pMSC and genetically modified MSCs that over-express IL-4 (IL4-MSCs) on steroid-associated ONFH in rabbits. Methods. Thirty-six male skeletally mature NZW rabbits received methylprednisolone acetate (20mg/kg) IM once 4 weeks before surgery. There were 6 groups:. CD alone – a 3 mm drill hole. + injection into the CD of:. hydrogel (HG) - 200 μl of hydrogel carrier. MSCs–1 million rabbit MSCs. pMSC - LPS (20 μg/ml) + TNFα (20 ng/ml) preconditioned MSCs. IL4-MSCs – rabbit IL-4 over-expressing MSCs. IL4-pMSCs – preconditioned IL-4 over-expressing MSCs. Eight weeks after surgery, femurs were harvested, and evaluated by microCT, biomechanical, and histological analyses. Results. Bone mineral density (BMD) and bone volume fraction (BVF) increased in the pMSC group compared to the CD and MSC groups . outside. of the CD area (p < 0.05, Fig.1). Similarly, the IL4-pMSC group was increased compared to the CD group (p < 0.05). The percentage of empty lacunae in the IL4-MSC group was significantly less than other groups . outside. the CD area (p < 0.05, Fig.2); however, IL4-MSC group had less trabecular bone formation . inside. the CD. The mechanical tests demonstrated no differences. Discussion. This rabbit steroid-associated ONFH model demonstrated that pMSC increased new bone formation after CD; IL4-MSCs that continuously secreted IL-4 decreased the number of empty lacunae . Immunomodulation of bone healing has the potential to improve bone healing after CD for early stage ONFH; these interventions must be applied in a temporally sensitive fashion. For any figures, tables, or references, please contact the authors directly

The aetiology, pathogenesis and clinical staging of osteonecrosis of the femoral head have been the subject of considerable discussion. The same is true regarding the treatment of such conditions, which could be non-operative (shockwaves, no traction, PEMFs) or operative (conservative methods or prosthetic substitution), depending on the age of the patient and the degree of compromise of the femoral head. During the period between 1972 and 2003 at the CTO Hospital of Turin, Italy, 54 patients underwent surgery. We used core decompression (forage biopsy) in 39 cases and in the other 15 cases free vascularised fibular grafting (microsurgical techniques). All the patients were at the initial stages of the condition (Steinberg I–IIIa), stages in which subchondral collapse had not yet occurred. Follow up average 125.6 months. The results were estimated according to the Harris Hip Score, which allows for a score in relation to pain upon motional, functional and clinical deformity. In light of our data, we can confirm that the advantage of the result is secondary to the appropriate use of surgical techniques in relation to the clinical staging of the pathology. We have, in fact, established a treatment protocol that calls for core decompression at stage 0 – IA and free vascularised fibular grafting at the more advanced stages that go from IB to IIIA

The efficacy of β-tricalcium phosphate (β-TCP) loaded with bone morphogenetic protein-2 (BMP-2)-gene-modified bone-marrow mesenchymal stem cells (BMSCs) was evaluated for the repair of experimentally-induced osteonecrosis of the femoral head in goats. Bilateral early-stage osteonecrosis was induced in adult goats three weeks after ligation of the lateral and medial circumflex arteries and delivery of liquid nitrogen into the femoral head. After core decompression, porous β-TCP loaded with BMP-2 gene- or β-galactosidase (gal)-gene-transduced BMSCs was implanted into the left and right femoral heads, respectively. At 16 weeks after implantation, there was collapse of the femoral head in the untreated group but not in the BMP-2 or β-gal groups. The femoral heads in the BMP-2 group had a normal density and surface, while those in the β-gal group presented with a low density and an irregular surface. Histologically, new bone and fibrous tissue were formed in the macropores of the β-TCP. Sixteen weeks after implantation, lamellar bone had formed in the BMP-2 group, but there were some empty cavities and residual fibrous tissue in the β-gal group. The new bone volume in the BMP-2 group was significantly higher than that in the β-gal group. The maximum compressive strength and Young’s modulus of the repaired tissue in the BMP-2 group were similar to those of normal bone and significantly higher than those in the β-gal group. Our findings indicate that porous β-TCP loaded with BMP-2-gene-transduced BMSCs are capable of repairing early-stage, experimentally-induced osteonecrosis of the femoral head and of restoring its mechanical function

Osteonecrosis (ON) of the femoral head is a condition that afflicts approximately 20 000 new patients per year, at an average age of 38. Twenty-five percent of the patients seen in our institution are under 25. Without treatment, most of these patients can be expected to need a total hip replacement (THR). However preservative procedures have a significant failure rate, and some, significant morbidity. It is desirable to avoid or delay THR, because most of the patients with ON will outlive the prosthesis, at the current state of the art. There are four issues that need to be weighed to arrive at a reasonable algorithm for the preservative treatment of ON; patient risk factors, morbidity of the proposed procedure, size of the lesion, and stage of the lesion. Risk – risk of outliving a THR. Age, sex, weight, general health, associated diseases, and level of activity all influence the longevity of a THR. The greater the risk, the greater the indication for a preservative procedure. Morbidity – There is a big difference between core decompression and a complex osteotomy. The overall risk of the procedure and the impact on THR must be considered. Size – Large lesions do much worse than small lesions at any stage. Stage – Pre-collapse lesions do better than post-collapse lesions. Using the above issues might lead the surgeon to do a THR on a 25-year old with a large post-collapse lesion or a core decompression on a 60-year old with a small symptomatic pre-collapse lesion. All of the issues must be considered to make sense out of a complex clinical situation

Background. Core decompression (CD) is effective to relieve pain and delay the advent of total hip arthroplasty (THA) for osteonecrosis of the femoral head (ONFH). However, the influence of CD on the subsequent THA has not been determined yet. Methods. Literatures published up to and including November 2018 were searched in PubMed, Embase and the Cochrane library databases with predetermined terms. Comparative studies of the clinical outcomes between conversion to THA with prior CD (the Prior CD group) and primary THA (the Control group) for ONFH were included. Data was extracted systematically and a meta- analysis was performed. Results. Overall, five retrospective cohort studies with 110 hips in the Prior CD group and 237 hips in the Control group were included and all the studies were of high quality in terms of Newcastle-Ottawa Scale. No difference in the rate of revision between the two groups showed (RR=1.92, P=0.46) after a minimal two-year follow-up. Postoperative Harris Hip Score were similar between the two groups in all the five studies. Two groups went through similar blood loss (P=0.38). But the operative time in the Prior CD group with tantalum rob was longer than that in the Control group (P=0.006, P<0,001, respectively in two papers). Moreover, intraoperative fracture and osteolysis or radiolucent lines were more likely to occur in the Prior CD group, though there is not statistical difference (RR=7.05, P=0.08; RR=3.14, P=0.05, respectively). Conclusion. The present evidence indicated that prior CD has no inferior effect on the survivorship nor hip scores to the subsequent THA. The operative time in the Prior CD group with tantalum rob was longer than that in the Control group. Attention should also be paid on possible more intraoperative fracture and postoperative osteolysis or radiolucent lines. For any figures or tables, please contact authors directly

Introduction. Osteonecrosis of the femoral head usually progresses to collapse in up to 70% to 80% of all cases. Previous studies have shown high failure rates with non-operative treatment, whereas, some surgical options including bone grafting, core decompression, osteotomy and arthroplasty have been recommended. Total hip arthroplasty and hemiarthroplasty, either cemented or cementless, are the last resort for improving the functional outcomes for the elderly. However, salvage of the femoral head in relatively young patients is widely advocated. Thus vascularized bone grafting has been recommended to salvage the collapsing femoral head. The purpose of this study was to evaluate the prognostic factors related to the outcome of the vascularized iliac bone grafting in the treatment of osteonecrosis of the femoral head. Methods. A retrospective case series review study is presented. Between April 1987 and April 2003, 47 patients (51 hips) in the authors' hospital underwent vascularized iliac bone grafting for the treatment of osteonecrosis of the femoral head. Three patients were lost to follow-up, thus, 44 patients (48 hips), 38 men and 4 women, were included in the study. All patients underwent operation by one experienced senior surgeon. Patients were grouped according to related risk factors, i.e., trauma, corticosteroid, alcohol, and an idiopathic group. A radiographic scale, the Ficat and Arlet classification system, was used for grading the osteonecrosis. We set the conversion to total hip arthroplasty as the end point for survival of vascularized iliac bone grafting in this study. Kaplan-Meier survivorship analysis was used to determine the significance with regard to the risk factors, age, Ficat and Arlet staging, gender, and side. Results. The Kaplan-Meier survivorship analysis showed that the 5-year overall rate of graft survival was 68.5% (95% confidence interval: 52.7% to 80.0%), 10-year overall rate of graft survival was 61.5% (95% confidence interval: 44.4% to 74.8%), and 61.5% (95% confidence interval: 44.4% to 74.8%) at 15 years. There was no significant difference between the groups regarding the prognostic factors of etiology, gender, side, and stage. The only significant parameter was the age that the patients older than 50 years had the worst 5-year survival rate of the femoral head (p<0.05). Conclusion. Vascularized bone grafting is a technically demanding procedure when compared to conventional core decompression or arthroplasty. However, this technique can preserve the femoral head from collapse and preclude the need for arthroplasty in young patients

Introduction: The purpose of this study was to review the preliminary clinical outcomes of a clinical study of a new implant for intervening in Stage I & II femoral head osteonecrosis. Materials & Methods: The porous tantalum (Hedrocel® Trabecular Metal, Zimmer Inc./Implex Corp.) is 80% porous with a modulus of elasticity similar to bone. The implant is 10 mm in diameter, offered in 70 – 130 mm lengths in 5 mm increments, and possesses threads for engagement of the lateral cortex. The investigation is an FDA regulated, prospective IDE study of the implant in comparison to core decompression for patients with Stage I or II osteonecrosis (Steinberg-UPenn). Patients exhibiting unilateral disease are randomized to an implant or core decompression (50–50 chance). All patients exhibiting bilateral disease receive the implant. Clinical outcome measures include HHS and SF-12 scored pre-op, at 6, 12, and 24 months, and radiographic data is collected at these same times, and at 6 and 12 weeks. Results: Prior to the clinical study, a custom case was performed in 1998, and a second in 1999. Since the study began in June 2000, 12 surgeries have been performed with the implant. All 14 patients are reportedly doing well. Radiographic review shows no evidence of abnormal bone density and no evidence of radiolucencies. All lesions appear similar to the pre-op condition. In one case, at 3-months, there is radiographic evidence that the implant has stabilized a slightly collapsed subchon-dral plate, and that new bone has formed in proximity to the tip of the implant. This patient exhibited mild pain at 8 weeks, which has since subsided. Discussion: The preliminary clinical experience with this implant is encouraging and suggests that mechanically supporting the subchondral plate with this implant is a viable method of intervening in the early stages of osteonecrosis

Introduction. Core decompression is used in precollapse lesions to forestall disease progression in avascular necrosis (AVN) of femoral head (FH). The author reports a new technique using reverse bone graft technique to effectuate core decompression. Aim. To prevent precollapse in Ficat Type 1&2 and revascularization using synthetic bone graft material. Methods. A 18 year female police trainee with Magnetic Resonance Imaging (MRI) confirming AVN Stage 2 Ficat, clinically painful hip not evident in x-rays consented to undergo this new technique. Reverse bone graft technique with a Coring reamer – Patent 5423823. A minimally invasive technique with lateral 2 cm incision introducing 8.5 mm core reamer to remove a core of bone up to the subchondral bone. The subchondral cyst decompressed and curetted under video recorded Image Intensifier (II). Demarcated avascular bone segment excised and bone graft reversed and inserted with cortical bone acting as a support to prevent collapse and the distal segment augmented using 5 grams of osteoconductive granular synthetic bone graft material based on calcium phosphate hydroxyapatite (HA 2500–5000 μm). Avascular segment histopathologically confirmed AVN. The metaphyseal entry was extrapoliated at the lateral cortex using the combined necrotic angle described by Kerboul in the anteroposterior and lateral views under II. Protected weight bearing for 2 months to prevent stress riser. Biomaterials. HA granules named as GranuMas™ developed under Intensified Research in Priority Areas (IRPA) Research Project (No. 03-01-03-0000-PR0026/05) and invented by the Advance Materials Research Centre (AMREC) and manufactured by GranuLab –Patent P1 20040748 fulfilling the criteria for American Society for Testing and Materials (ASTM) F1185-88(1993) Standards which is ‘Standard Specification for Composition of Ceramic Hydroxyapatite for Surgical Implants’. Derived from Malaysian limestone, ranging from 200–5000 μm gamma sterilized. Results. After 6 months, there was no collapse of subchondral bone and the FH showed revascularization along bone grafted site with viable graft and increased radiotracer activity using 99-Tc MDP Bone Planar Scintigraphy. Clinical analysis follow up at 2 years was descriptive rather than statistical with a x-ray evident incorporated graft and with pain free full range of movement. Discussion. Reduction in intraosseous pressure is achieved by using large bore 8.5 mm coupled with HA granules promoting revascularization. The core tract entering through the metaphyseal region reduces risk of subtrochanteric fracture a potential complication of vascularized fibular grafts and with less morbidity with other treatment methods for osteonecrosis of the femoral head. The concept can be extended in introducing stem cell and biologic material to treat AVN. Conclusion. This technique is minimally invasive and effective in young patients with early stage of FH AVN and has shown revascularization along the bone grafted site

Introduction: Evidence-based medicine is a form of practice in which the physician accesses relevant, state-of-the-art research findings to guide the care of the individual patient (Gordon and Cameron, 2000). Therefore, evidence-based medicine should influence the decision making process when developing a treatment algorithm for early stage osteonecrosis. It was the purpose of this project to explore the literature concerning surgical options that are used currently to treat early stage osteonecrosis. Materials and Methods: Literature searches were conducted using PubMed (National Library of Medicine, USA) to identify journal articles pertaining to the treatment of pre-arthrosis osteonecrosis during the past decade. The articles were screened to include only those with greater than 5 patients and greater than two year follow-up. Results: Published reports in medical journals included: core decompression with and without nonvascular grafting (18); core decompression augmented with BMP or bone marrow cells (2); bone cement (1); vascularized graft – fibular or iliac (10); osteotomy (26); osteotomy and vascularized grafts (3); trap-door procedure (2); and hemiarthroplasty/resurfacing arthroplasty (9). There was one review of nonoperative treatment, but no clinical studies. There were only a few case reports concerning osteochondral graft/osteochondroplasty; which did not meet the inclusion criteria. Several classification systems were used: Ficat and Arlet (55%); University of Pennsylvania / Steinberg (21%); Japanese Investigational Committee (13%); Marcus (2%); Myers (3%); ARCO (5%), and other (1%). A majority of reports included follow-up of 5 years or greater (91%). Most studies (91%) were not randomized, control-matched, or prospective. Discussion: Several surgical options are available for the treatment of pre-arthrosis osteonecrosis. However, it is not possible to apply evidence-based medicine practices to the research relating to the treatment of osteonecrosis as most of the research is not controlled and not comparative. This represents a substantial void in our knowledge base concerning osteonecrosis which remains to be filled

Introduction. This study reports the results of percutaneous autologous bone marrow grafting in 62 patients with corticosteroids treatment who had one hip osteonecrosis treated with bone marrow (BM) injection and the other contralateral hip osteonecrosis with core decompression (CD) alone. Only patients with bilateral symptomatic osteonecrosis and with those hips at stage I or II (as defined by Steinberg) were included in this study. Material and Methods. Between 1988 and 1995, 62 consecutive patients (28 males and 34 females) were included in this study. These patients had a mean age of 31 years (range 18 to 34 years) at the time of the onset of symptoms. The average follow-up was 17 years (range, 15 to 20 years). An average of 152 + 16 milliliters of marrow was aspirated from the iliac crest. The number of stroma progenitor that was transplanted was estimated by counting the Fibroblast Colony Forming Units which express type I and type III collagen. The bone marrow graft obtained after concentration contained average 4889 + 716 progenitors per cubic centimeter (range 3515 to 6293 per cubic centimeter). Each hip received a mean number of thirty cubic centimeters of bone marrow graft (range 27 to 35 cubic centimeters). The average total number of CFU-F injected in each hip was therefore 147 × 103 cells (range 119 × 103 to 195 × 103 cells). Results. Clinical results were determined by the change in Harris hip scores from preoperative evaluation to the last follow-up visit, by the change in the radiographic progression and by the need of subsequent total hip arthroplasty. Bone marrow grafting afforded better reduction in pain, effected a reduction with time in the number of hips that progressed to collapse, and delayed the need for total hip replacement. Ten hips had collapsed and needed arthroplasty at the most recent follow-up after bone marrow grafting, compared to 45 after core decompression. For hips with collapse, the mean survival time before collapse was 71.2 months (43.35- 60.96; 95% CI) for the bone marrow graft group and 38.5 months for the control group (13.2–39.74; 95% CI). With the number available, there was a positive correlation (Spearman's test) between the duration of clinical survival before collapse and the number or concentration of CFU-F and CFU-GM in the graft in the CD group. These results are explained by the fact that bone marrow injection improved the repair process on MRI and on histology. Overall, 10 hips with bone marrow injection showed a total regression of the signal, 59 hips showed a partial reduction (42 with BM and 17 with CD) and 55 hips did not show a significant reduction (10 with BM and 45 with CD). Conclusion. Bone marrow grafting afforded better reduction in pain, reduction in the number of collapses, delayed the need for total hip replacement, and improved the repair process on MRI and on histology

Introduction: Treatment of osteonecrosis continues to be a challenging problem in orthopedic practice. Arthroplasty is generally successful but long-term results are inferior especially in young adults. Alternative treatments such as core decompression and trap-door procedures provide only temporary benefits and need much improvement. The replacement of necrotic bone to promote osteogenesis and angiogenesis and healing subchondral bone are future approaches. Autogenous cancellous bone is the preferred graft material but its supply is limited. Allografts are useful but not as desirable as autografts. Substitutes for bone grafts have been actively researched but few are available currently. In this study, we have attempted to use genetically engineered bone marrow stem cells in order to enhance the healing of a bone defect in a mouse model. Materials and Methods: A bone marrow stem cell was cloned from Balb/c mice and transfected with LacZ and neomycin resistance genes. The cells were cultured for 7 to 10 days and both the osteoblastic and angiogenic properties of the cells were examined using Northern blots to detect osteocalcin and VEGF gene expression. The cells were also analyzed for alkaline phosphatase activity to demonstrate the osteoblastic phenotype of the cells. A suspension containing 2 x 10. 7. cells/ml phosphate buffered solution was prepared for cell transplantation. A total of forty-eight, 8-week old Balb/c mice were used in this study. A 1.2 mm defect was created bilaterally with an electric drill in the femurs of 24 mice to mimic the core decompression and trap-door procedures. 2 x 10. 6. cells were transplanted into each defect of the right femur while the left femur served as a control trap-door defect which was injected with PBS but without cells. An equal number of cells were injected either at subcutaneous sites, in the hindquarter muscles, or into the renal capsule (8 mice in each site) to evaluate ossification at ectopic sites. Animals were sacrificed at 2, 4, 6 and 8 weeks. Defect repair was evaluated radiographically and the contribution to osteogenesis by transplanted cells was studied histomorphometrically using tissue sections stained with X-gal as well as biochemically on DNA extracts using primers for the neomycin resistance gene. Results: Radiopaque tissue appeared two weeks after the cells were transplanted into bone defects, muscle, subcutaneous sites, and the renal capsule. Histological analysis demonstrated that these tissues consist of newly formed bone from transplanted cells that stained positively with X-gal and contained neo DNA. The repair tissue did not contain cartilaginous areas indicating that ossification surrounding the D1-BAG cells was not through the endochondral process. At four weeks, 4 of 6 femora showed a defect that was filled with new bone. At 6 weeks, all of the defects (6 of 6) contained fully restored bone. However, in the control side that was injected with PBS (no cells) only 2 of 6 at 4 weeks, 3 of 6 at 6 weeks, and 5 of 6 at 8 weeks showed complete repair. All histological sections of bone defects (n = 24) were examined histomorphometrically using a computerized image analysis system. Transplantation of marrow stem cells into bone defects produced more bone at an earlier time point than controls and, the process of enhanced ossification continued throughout the healing process. Discussion: The cloned bone marrow stem cell can directly form bone after transplantation into bone defects and into ectopic sites, indicating that the in vitro expanded bone marrow stem cells can serve as a grafting material to enhance healing of bone defects and the treatment of osteonecrosis. In addition, this study demonstrates that genetic labelling is a useful tool in studies of cell differentiation in vivo and that bone marrow stem cells may be useful as a carrier of genetically-engineered factors in the treatment of skeletal diseases

Osteonecrosis (ON) is a debilitating condition that can progress to severe arthritis of the hip. While its exact pathogenesis remains poorly understood, ON is known to be associated with risk factors such as corticosteroid use, alcoholism, and autoimmune disease. Initial radiographic evaluation can reveal sclerotic and cystic changes in the femoral head, which are usually the first clues in diagnosis. Despite these indicators, plain radiographs generally are not sufficient for diagnosis, therefore requiring subsequent magnetic resonance imaging (MRI) studies. Moreover, performing an appropriate assessment of these imaging modalities can help guide the course of treatment. Treatment options are aimed at slowing or stopping the onset of femoral head collapse and include non-operative management, joint preservation procedures, and total joint arthroplasty. Patients at risk of developing ON may benefit from early diagnosis because the characteristic small or medium-sized pre-collapse lesions that are associated with this stage can often be treated with a non-operative or joint preservation approach. However, patients typically present with advanced disease progression and sometimes an unsalvageable joint, thereby necessitating more invasive operative intervention. Surgical modalities include the use of osteotomy, core decompression, vascular grafts, bone graft substitutes, resurfacing, and finally, total hip arthroplasty. Additionally, reports from the past several decades describe improved outcomes and survivorship of these surgical treatment options. Therefore, our purpose is to highlight recent evidence regarding the management of ON with emphasis on the various forms of operative intervention as well as their outcomes

Introduction. For many years, minimally invasive joint-preserving regenerative therapy has been desired for the early stages of osteonecrosis of the femoral head (ONFH). In an animal study using adult rabbits, we reported that a single local injection of rhFGF-2-impregnated gelatin hydrogel, which has superior slow-release characteristics, suppresses the progression of femoral head necrosis. The purpose of this study was to evaluate the safety and clinical outcomes of a single local administration of rhFGF-2-impregnated gelatin hydrogel for the precollapse stage of ONFH. Patients and Methods: Ten patients with femoral heads up to precollapse stage 2 underwent a single local administration of 800-µg rhFGF-2-impregnated gelatin hydrogel and were followed up for two years. The eligibility criteria were age between 20 and 80 years and presence of ONFH at precollapse stage 1 or 2 according to the classification system for ONFH developed by the Japanese Investigation Committee of Health and Welfare. Primary outcomes included adverse events and complications. Secondary outcomes included changes in Harris Hip Scores (HHS), visual analog scale pain scores (VAS), the University of California, Los Angeles (UCLA) activity rating scores, radiological changes as determined via radiographs, computed tomography (CT) scans, and magnetic resonance imaging (MRI) of the hip joint. Results: We included five men (five hips) and five women (five hips), with a mean age of 39.8 years (range: 29–53 years) at the time of surgery. Eight patients had bilateral ONFH, three had already undergone THA on the contralateral side. Eight patients were receiving treatment with corticosteroid therapy, and two patients overused alcohol. Stage 1 and 2 disease was present in one and nine patients, respectively. One patient each had type A, type B, and type C1 disease, whereas seven patients had a type C2 lesion. All Adverse events were recovered without problem. The surgery was performed with a minimally invasive technique based core decompression (1 cm of skin incision), and walking was allowed from the day after surgery. Mean clinical scores improved significantly after three year compared with before surgery (before vs. after: VAS for pain, 21.2 vs. 5.3 mm; UCLA activity score 5.5 vs. 6.6; HHS, 81.0 vs. 98.4 points, respectively). There was only one case of femoral head collapse, and it had the greatest necrosis volume fraction and was considered to be in the early collapse stage at the time of operation. The other nine cases did not involve ONFH stage progression, and collapse was prevented. CT images and recent MRI postoperatively confirmed bone regeneration and reduction of the necrotic area. Conclusion: Clinical application of rhFGF-2-impregnated gelatin hydrogel for patients with precollapse stage of ONFH was feasible and safe. Our research is ongoing, further phase II multiple center study has been started in January 2016

Osteonecrosis of the femoral head is a complex pathologic process with many aetiological factors. Factors most often mentioned in the literature are mechanical disruption (hip trauma or surgery), steroid use, smoking, haemoglobinopathies and hyperlipidaemia. 1. Our case depicts a rare association of crack cocaine related to osteonecrosis of the femoral head which has never been reported in the available literature. Case Report: A 32 year old man was referred to our Orthopaedic clinic with right hip pain. He had a 9 pack-year history of cigarette smoking and had also smoked crack cocaine between ages 20 to 28; shortly after this the hip pain started. He denied antecedent injury. He had undergone a steroid injection into his right ankle abroad for swelling one year before referral, which was after onset of hip pain. MRI of his hip previously performed abroad had been normal. The patient had an indoor job and was otherwise fit and well. On examination he had reduced of movement in his right hip with 5–10 degrees of fixed flexion deformity. Plain radiography demonstrated cyst formation and sclerosis of both femoral heads. Repeat MRI confirmed bilateral osteonecrosis, worse on the right with risk of head collapse. The patient underwent bilateral core decompressions. Subsequent follow-up demonstrated a mobile patient with no need for arthroplasty and he was discharged after two years. Osteonecrosis is caused by the coagulation of the intra-osseous microcirculation leading to thrombosis formation and eventual reduction in osseous blood supply. Steroid use is associated with increased risk of osteonecrosis to the femoral head, however in these cases the patients often undergo either direct local or systemic infiltration of steroid. In this case steroid was administered after symptoms began to a far distant site and therefore cannot be the cause. Cigarette smoking is also known to cause osteonecrosis. Our patient had smoked cigarettes for fourteen years without problems, and it was after he ceased to smoke crack cocaine that his symptoms began. Cocaine blocks voltage-gated sodium-channels causing vasospasm. It is known to cause nasal and facial bone osteonecrosis due to its common intranasal method of delivery. We postulate that in this case crack cocaine was a synergistic factor towards development of femoral head osteonecrosis