Bin Shen

Are the results of multiple drilling and alendronate for osteonecrosis of the femoral head better than those of multiple drilling? A pilot study.

OBJECTIVESnThe treatment of osteonecrosis of the femoral head (ONFH) remains controversial. A recently proposed treatment is multiple drilling core decompression combined with systemic alendronate as a femoral head-preserving procedure for ONFH. However, it is not known whether alendronate enhances the risk of collapse. We wondered whether the combined procedure could delay or prevent progression of ONFH compared to multiple drilling alone.nnnMETHODSnPatients with early-stage ONFH were randomly assigned to be treated with either multiple drilling combined with alendronate (47 patients, 67 hips) or multiple drilling alone (46 patients, 60 hips). We defined failure as the need for THA or a Harris score less than 70. The minimum follow-up was 48 months for the 77 patients completing the protocol.nnnRESULTSnAfter a minimum 4-year follow-up, 91% (40/44) of patients with Stage II disease and 62% (8/13) of patients with Stage III disease had not required THA in alendronate group, compared to 79% (31/39) of patients with Stage II disease and 46% (6/13) of patients with Stage III disease had not required THA in control group (P=0.12, P=0.047, respectively). Small or medium and central lesions had a better successful rate in both groups. Risk factors did not seem to affect the clinical successful rate of this procedure.nnnCONCLUSIONSnMultiple small-diameter drilling core decompression combined with systemic alendronate administration can reduce pain and delay progression of early-stage ONFH. Even in Ficat IIA and III hips, some benefit was obtained from this approach at least delay in the need for THA.

Changes in Cobalt and Chromium Levels After Metal-on-Metal Hip Resurfacing in Young, Active Chinese Patients

Metal-on-metal resurfacing arthroplasty is increasingly being performed in young, active patients. Serum and urine metal ion levels are monitored in these patients to assess the physiologic effects of metal-on-metal wear on them. The aim of our prospective study was to evaluate the serum and urine levels of cobalt (Co) and chromium (Cr) in young (age, ≤50 years), active Chinese patients who had undergone metal-on-metal hybrid resurfacing arthroplasties. Levels were measured preoperatively using atomic absorption spectrometry and then sequentially at 3, 6, 9, 12, and 24 months after surgery. For both serum and urine Co and Cr, there was an initial increase to a peak at 6 months, followed by a gradual decline after 6 months, whereas renal function was normal during the study the 2-year study period. There was no radiographic evidence of component loosening. All implants were functioning well. Further long-term studies are needed to observe clinical outcomes and to determine the physiologic effects of the wearing process.

The effect of posterior tibial slope on knee flexion in posterior-stabilized total knee arthroplasty

PurposeTo evaluate and quantify the effect of the tibial slope on the postoperative maximal knee flexion and stability in the posterior-stabilized total knee arthroplasty (TKA).MethodsFifty-six patients (65 knees) who had undergone TKA with the posterior-stabilized prostheses were divided into the following 3 groups according to the measured tibial slopes: Group 1:xa0≤4°, Group 2: 4°–7° and Group 3:xa0>7°. The preoperative range of the motion, the change in the posterior condylar offset, the elevation of the joint line, the postoperative tibiofemoral angle and the preoperative and postoperative Hospital for Special Surgery (HSS) scores were recorded. The tibial anteroposterior translation was measured using the Kneelax 3 Arthrometer at both the 30° and the 90° flexion angles.ResultsThe mean values of the postoperative maximal knee flexion were 101° (SD 5), 106° (SD 5) and 113° (SD 9) in Groups 1, 2 and 3, respectively. A significant difference was found in the postoperative maximal flexion between the 3 groups (Pxa0<xa00.001). However, no significant differences were found between the 3 groups in the postoperative HSS scores, the changes in the posterior condylar offset, the elevation of the joint line or the tibial anteroposterior translation at either the 30° or the 90° flexion angles. A 1° increase in the tibial slope resulted in a 1.8° flexion increment (rxa0=xa01.8, R2xa0=xa00.463, Pxa0<xa00.001).ConclusionAn increase in the posterior tibial slope can significantly increase the postoperative maximal knee flexion. The tibial slope with an appropriate flexion and extension gap balance during the operation does not affect the joint stability.Level of evidenceRetrospective comparative study, Level III.

Efficacy of celecoxib, meloxicam and paracetamol in elderly Kashin-Beck Disease (KBD) patients

The objective of this study was to compare the efficacy and tolerability of celecoxib, meloxicam and paracetamol in late Kashin-Beck disease. Adults (nu2009=u2009168) with Kashin-Beck disease were randomised in clusters to receive six week courses of celecoxib 200xa0mg once daily, meloxicam 7.5xa0mg once daily or paracetamol 300xa0mg three times daily. Efficacy assessments included overall joint pain intensity and Western Ontario and McMaster Universities Osteoarthritis Index subscales; tolerability was evaluated by adverse event and physician reporting. Celecoxib and meloxicam were efficacious in relieving pain and improving stiffness, but unable to improve physical function after sixxa0weeks. Paracetamol was efficacious in relieving pain, but unable to improve morning stiffness and physical function after sixxa0weeks. Celecoxib and meloxicam provide predictable and sustained relief from pain and stiffness. Paracetamol can relieve the pain. None of the treatments improved impaired physical function in Kashin-Beck disease.

Cementless Total Hip Arthroplasty in Chinese Patients with Osteonecrosis of the Femoral Head

This study was designed to evaluate the midterm (> or = 5 years) clinical and radiographic outcomes of the cementless total hip arthroplasty in 64 Chinese patients (72 hips), which revealed that the mean Harris hip score increased from an average of 44.0 points before operation to 92.4 points at the last follow-up. Excellent results were achieved in 60 hips (83%). No loosening of the components was observed radiographically. No revision of the femoral components was required. Only one focal area of pelvic osteolysis in 1 hip (1%), which requires a revision, and some small focal areas of femoral osteolysis in 12 hips (17%) were observed. The mean linear wear rate was 0.125 mm/y. The survival rate of the acetabular and femoral components for radiographic loosening was 100% (95% confidence interval, 0.93-1.0) and for revision was 98.61% (95% confidence interval, 0.95-1.0). This study indicated that the cementless total hip arthroplasty in patients with osteonecrosis of the femoral head has a satisfactory midterm clinical and radiographic outcomes, but the long-term effect should be further studied.

Midterm Results of Uncemented Acetabular Reconstruction for Posttraumatic Arthritis Secondary to Acetabular Fracture

At an average of 6.3 years after surgery, we evaluated midterm results of uncemented acetabular reconstruction in 31 hips with posttraumatic arthritis that developed after acetabular fracture. Patients were categorized by previous fracture treatments (open-reduction group and conservative-treatment group) and fracture patterns (simple group and complex group). Surgery duration and blood loss were greater in the open-reduction and complex groups than in the conservative-treatment and simple groups (P < .05). The mean Harris Hip Score increased from 49 before surgery to 89 after surgery. Survival with revision or radiographic acetabular loosening as an end point was 100%. Fracture treatments and patterns were associated with increased surgery duration and increased blood loss. Open reduction and internal fixation of a fracture favor anatomical restoration of the hips rotational center.

Effects of an anticoagulant and a lipid-lowering agent on the prevention of steroid-induced osteonecrosis in rabbits

This study was designed to evaluate the effects of the combined treatment with an anti‐coagulant (enoxaparin) agent and a lipid‐lowering agent (lovastatin) on prevention or decrease in the occurrence of steroid‐induced osteonecrosis in rabbits. A total of 112 rabbits, which were injected intramuscularly with 20u2003mg/kg of methylprednisolone acetate were divided into four groups and treated as follows: one group received enoxaparin combined with lovastatin (EL; nu2003=u200330), another received enoxaparin alone (EA; nu2003=u200328), another received lovastatin alone (LA; nu2003=u200328) and the last received no treatment (non‐prophylactic; NP, nu2003=u200326). Haematological examination for serum lipid levels and prothrombin time was carried out and both femora and humeri were examined histopathologically for the presence of osteonecrosis (ON) before injection and at 2, 4, 8 and 12u2003weeks after the injection. The incidence of ON in the EL group (15%) was significantly lower than that observed in the NP group (68%). The incidence in the EA and LA groups was also significantly lower than that in the NP group (31%, 35%vs. 68%). The fat cell sizes of the bone marrow in both EL (46.49u2003±u20031.27u2003μm) and LA (50.8u2003±u20032.31u2003μm) groups were lower than in the NP group (59.89u2003±u20036.33u2003μm). The prothrombin time was prolonged and plasma lipid levels were reduced in the EL group during the study. Combination treatment with an anti‐coagulant agent and a lipid‐lowering agent can reduce the incidence of steroid‐induced ON in rabbits. Future evaluation in clinical practice is necessary.

Circulating platelet-derived microparticles and endothelium-derived microparticles may be a potential cause of microthrombosis in patients with osteonecrosis of the femoral head

INTRODUCTIONnTo test the hypothesis that the platelet microparticle (PMP) and endothelial microparticle (EMP) may contribute to the hypercoagulability associated with microvascular thrombosis in patients with nontraumatc osteonecrosis of the femoral head (ONFH).nnnMATERIALS AND METHODSnThe study comprised 46 patients who had been diagnosed with ONFH and 20 control subjects. The plasma was ultracentrifuged, and then PMPs and EMPs were examined by the flow cytometry. The thrombotic and fibrinolytic disorders were investigated.nnnRESULTSnThe numbers of PMPs expressing P-selectin and CD42a and EMPs expressing E-selectin and CD31 in the ONFH patients were significantly higher than those in the controls (P<0.001). The number of MPs was correlated with the level of the serum C-reactive protein (CRP) (r=0.661, P<0.001), but there was a poor correlation between the MPs counts and the risk factors for ONFH (P>0.05). The mean levels PAI-1, F1+2, and TAT were higher in the patients with ONFH than in the controls (P<0.05).nnnCONCLUSIONSnThe elevated numbers of PMPs and EMPs may contribute to hypercoagulability in the ONFH patients. This may provide important pathophysiological insights into the hypercoagulability associated with nontraumatic ONFH and have implications for pharmacological prevention and treatment of ONFH.

A randomized, single-blind comparison of the efficacy and tolerability of hyaluronate acid and meloxicam in adult patients with Kashin–Beck disease of the knee

The aim of this study was to prospectively evaluate the efficacy and tolerability of hyaluronic acid (HA) and meloxicam for the treatment of knee pain due to Kashin–Beck disease (KBD). A total of 162 patients with KBD-based knee pain were randomly assigned to treatment with a 3-week course of HA (nu2009=u200980) and a 12-week course of meloxicam (nu2009=u200982). Clinical assessments for each patient were made at 0 (baseline), 1, 2, 4, 8, and 12xa0weeks. The primary efficacy measure was visual analog scale (VAS) pain score. Second efficacy measures comprised the Western Ontario and McMaster Universities (WOMAC) A (pain), B (stiffness), and C (function) scores as well as patients’ and physicians’ global assessments. Tolerability was evaluated based on adverse events (AEs) and physician reporting. The VAS rapidly decreased in both groups over 12xa0weeks. The VAS improvement observed in HA group was lower at weekxa01 (pu2009=u20090.001) but better at weeksxa08 and 12 (pu2009<u20090.001) than the meloxicam group, which were supported by the secondary variables of WOMAC A (pu2009=u20090.001) and WOMAC C (pu2009<u20090.001) scores and the global assessments of the patients and their physicians (pu2009=u20090.020 and 0.003, respectively). No serious AEs were reported, and the overall incidence of AEs among patients treated with meloxicam was higher than in patients treated with HA (pu2009=u20090.012). This study suggests that intra-articular injection of HA and administration of oral meloxicam should be efficacious and well tolerated in the treatment of knee pain due to KBD; the onset of action of meloxicam was faster than that of HA, whereas HA therapy resulted in a more prolonged increasing improvement of symptoms than meloxicam. In addition, HA treatment was likely superior to meloxicam with respect to tolerability. Other randomized double-blind studies are needed to confirm the findings of our open-label study.

Survivorship comparison of all-polyethylene and metal-backed tibial components in cruciate-substituting total knee arthroplasty—Chinese experience

Considering its cost saving, the all-polyethylene tibial component is of potential interest in developing countries like China. But to our knowledge, a survivorship comparison of all-polyethylene and metal-backed tibial components in posterior cruciate ligament-substituting total knee arthroplasty (PS-TKA) has not been studied in China previously. Using survivorship analysis, we have studied the midterm outcome of 34 cemented PS-TKA using an all-polyethylene tibial component and of 34 cemented PS-TKA using a metal-backed tibial component which has an identical articular surface with all-polyethylene tibial components. All operations were performed by the same group of surgeons; 58 patients underwent a unilateral operation and five patients a bilateral operation. These patients had a mean follow-up of 5.9xa0years (range: 5–7xa0years); three patients were lost to follow-up and one was revised for infection. No significant difference between the two groups was reported regarding HSS scores, ROM, clinical and radiographic parameters measured and survival rates. Although the Asian lifestyle includes more squatting and bending of the knee, the results of this series of TKA using all-polyethylene tibial components in Chinese people are comparable to the satisfactory results of other reported all-polyethylene series whose patients are mainly Western people. Considering its cost saving and excellent clinical result, the all-polyethylene tibial component is of potential interest in developing countries.RésuméLes plateaux tibiaux tout polyéthylène APTC permettent une économie financière aux niveaux des implants et ont un intérêt potentiel pour la Chine. En utilisant une analyse avec courbe de survie, nous avons réalisé un suivi moyen de 5,9 ans (5 à 7 ans) pour 34 prothèses postéro stabilisées cimentées PS-TKA en utilisant un plateau tout polyéthylène APTC. Et 34 prothèses avec un métal back MBTC avec la même surface de glissement que l’APTC. Il n’y a pas de différence significative entre les deux groupes si l’on considère le score HSS, la mobilité et la clinique ainsi que les paramètres radiographiques et les courbes de survie. Les courbes de survie à 5,9 ans sont de 93,55% pour le groupe APTC et de 93,75% pour le groupe MBTC. Cependant, le mode de vie asiatique nécessitant des flexions antérieures et une flexion importante des genoux ont un résultat identique chez les chinois (en utilisant une APTC) avec des résultats comparables et tout à fait satisfaisants comparées aux autres séries de plateaux tout PE des populations occidentales. Si l’on considère l’économie réalisée et les excellents résultats cliniques des prothèses APTC avec un composant tout polyéthylène, ceux-ci sont intéressants pour ces pays en voie de développement.