BACKGROUND:The modular prosthesis applied in hip arthroplasty has the greatest advantages of making operations more flexible,individually meeting the needs of different patients,and reducing the chance of prosthesis revision.Even in the case of revision surgery,the procedure can be simplified,minimizing bone destruction and loss.However,the possible complication of intra-prosthetic dissociation after operation is still an important issue that cannot be ignored in clinical practice,which may bring disastrous consequences once it occurs.Therefore,having a comprehensive understanding of the epidemiological characteristics,imaging interpretation,mechanism and treatment of this complication is of great importance for joint surgeons to develop appropriate scientific and reasonable prevention and treatment strategies.OBJECTIVE:To review the research progress on the complication of intra-prosthetic dissociation after hip arthroplasty.METHODS:The WanFang and PubMed databases were retrieved for original research,reviews,comments,case reports,and meta-analyses published from January 1,1978 to August 31,2024 on the complications of intra-prosthesis separation after hip replacement.The epidemiological characteristics,imaging interpretation,occurrence mechanism,and treatment strategies of intra-prosthesis separation complications after hip arthroplasty were reviewed by summarizing and analyzing the literature.RESULTS AND CONCLUSION:(1)Intra-prosthetic dissociation is a comparatively uncommon complication.This complication may pose a higher risk in the early postoperative period for patients who are middle-aged with higher activity level,overweight or preoperatively diagnosed with osteoarthritis.(2)Although specific signs under X-ray or ultrasound imaging can facilitate the diagnosis of intra-prosthetic dissociation,MRI and CT are deemed more valuable in diagnosing polyethylene liners dissociation.(3)The cause of intra-prosthetic dissociation may be related to factors such as intra-prosthetic impingement,prosthesis-related factors,improper positioning of the prosthesis,and iatrogenic disassociation.(4)The treatment strategy should be determined based on comprehensive factors such as the type of intra-prosthetic dissociation,patient's physical condition and comorbidities.

BACKGROUND:The modular prosthesis applied in hip arthroplasty has the greatest advantages of making operations more flexible,individually meeting the needs of different patients,and reducing the chance of prosthesis revision.Even in the case of revision surgery,the procedure can be simplified,minimizing bone destruction and loss.However,the possible complication of intra-prosthetic dissociation after operation is still an important issue that cannot be ignored in clinical practice,which may bring disastrous consequences once it occurs.Therefore,having a comprehensive understanding of the epidemiological characteristics,imaging interpretation,mechanism and treatment of this complication is of great importance for joint surgeons to develop appropriate scientific and reasonable prevention and treatment strategies.OBJECTIVE:To review the research progress on the complication of intra-prosthetic dissociation after hip arthroplasty.METHODS:The WanFang and PubMed databases were retrieved for original research,reviews,comments,case reports,and meta-analyses published from January 1,1978 to August 31,2024 on the complications of intra-prosthesis separation after hip replacement.The epidemiological characteristics,imaging interpretation,occurrence mechanism,and treatment strategies of intra-prosthesis separation complications after hip arthroplasty were reviewed by summarizing and analyzing the literature.RESULTS AND CONCLUSION:(1)Intra-prosthetic dissociation is a comparatively uncommon complication.This complication may pose a higher risk in the early postoperative period for patients who are middle-aged with higher activity level,overweight or preoperatively diagnosed with osteoarthritis.(2)Although specific signs under X-ray or ultrasound imaging can facilitate the diagnosis of intra-prosthetic dissociation,MRI and CT are deemed more valuable in diagnosing polyethylene liners dissociation.(3)The cause of intra-prosthetic dissociation may be related to factors such as intra-prosthetic impingement,prosthesis-related factors,improper positioning of the prosthesis,and iatrogenic disassociation.(4)The treatment strategy should be determined based on comprehensive factors such as the type of intra-prosthetic dissociation,patient's physical condition and comorbidities.

BACKGROUND:Compared with total knee arthroplasty,unicondylar knee arthroplasty has such advantages as quick recovery,low cost and good proprioception,but its high revision rate after operation is also a problem that cannot be ignored.At present,the reasons for the high revision rate after unicondylar knee arthroplasty are not completely clear.Therefore,preoperative strict control of surgical indication may be crucial to improve postoperative outcome and reduce revision rate after unicondylar knee arthroplasty.As an index commonly used in the measurement of imaging,the evaluation of joint space width may have important clinical reference value in the selection of indications for unicondylar knee arthroplasty. OBJECTIVE:To review the measurement of joint space width and its effect on the curative effect and outcome of medial unicondylar knee arthroplasty. METHODS:WanFang and PubMed were used to search the relevant literature published from January 1,1950 to June 1,2023 on the evaluation factors of curative effect of unicondylar knee arthroplasty and the influence of joint space width on the curative effect of unicondylar knee arthroplasty.By summarizing and analyzing the literature,the measurement methods of joint space width,the influence of preoperative medial compartment joint space width on the curative effect of medial compartment joint space width,and the influence of postoperative lateral compartment joint space width on the outcome were reviewed. RESULTS AND CONCLUSION:(1)Although many methods have been used to study and measure knee joint space width,X-ray measurement of joint space width under weight-bearing position is still a common method in daily orthopedic practice to assess the progression of osteoarthritis,and it can moderately reflect the thickness of cartilage.(2)Preoperative medial compartment joint space width of knee joint can affect the efficacy of medial movable platform after unicondylar knee arthroplasty.Patients with knee osteoarthritis whose medial joint space width/lateral joint space width ratio is<40%or medial joint space width≤2 mm may be more suitable for medial movable platform unicondylar knee arthroplasty.(3)Changes in lateral compartment joint space width after medial unicondylar knee arthroplasty also have a certain impact on outcome.Improving the joint matching degree of lateral compartment after surgery can delay the progression of lateral compartment joint degeneration and reduce the prosthesis revision rate.However,relevant clinical studies are still lacking.In conclusion,the imaging measurement of joint space width has important clinical reference value for evaluating the postoperative efficacy and prognosis of medial unicondylar knee arthroplasty.

Objective To explore the effect of primary exchange reamed nailing (ERN) and augmentation compression plating (ACP) combined with autogenous bone grafting (ABG) on health-related quality of life in patients with dystrophic or atrophic nonunion of femoral shaft after intramedullary nailing. Methods The study used a prospective study method. Sixty- two patients with femoral shaft nonunion after intramedullary nailing from August 2010 to October 2016 were selected, and the patients were divided into ERN group (group A, 32 cases) and ACP group (group B, 30 cases) by random digits table method. In group A, isthmus nonunion was in 18 cases (56.2％), and non-isthmus nonunion in 14 cases (43.8％); in group B, isthmus nonunion was in 16 cases (53.3％), and non-isthmus nonunion in 14 cases (46.7％ ). The health- related quality of life was compared between 2 groups, including physical component summary (PCS) and mental component summary (MCS) in the- 12- item short form health survey (SF- 12), brief pain inventory- severity (BPI- S) and brief pain inventory- interference (BPI- I). Results Fifty-four patients were followed-up for more than 1 year, and the mean follow-up time was 18.3 (13 to 37) months. All patients successfully achieved bone union, and the mean time was 5.8 (4 to 8) months. Significant improvements in terms of SF-12 PCS and SF-12 MCS score were noted after operation for patients with isthmus nonunion in both groups (t=3.148, 2.156, 2.456 and 2.559; P < 0.05), but there were no significant differences before and after operation in group A with non-isthmus nonunion (P >0.05). At the last follow-up, SF-12 PCS and SF-12 MCS in group B were significantly improved compared with those in group A: (45.2 ± 5.8) scores vs. (33.6 ± 4.7) scores and (48.8 ± 6.5) scores vs. (39.4 ± 5.6) scores, and there were statistical difference (P<0.05); SF-12 BPI-S and BPI-I showed obvious relief: (4.6 ± 2.1) scores vs. (6.2 ± 2.5) scores and (5.2 ± 1.9) scores vs. (6.8 ± 2.7) scores, and there were statistical differences (P<0.05); however there were no statistical difference in SF-12 PCS, SF-12 MCS, BPI-S and BPI- I between 2 groups (P>0.05). Conclusions Compared with ERN combined with ABG, ACP combined with ABG can significantly improve the quality of life in patients with dystrophic or atrophic nonunion of femoral shaft after intramedullary nailing. It has greater advantage on the improvement of health-related quality of life, especially for patients with non-isthmus nonunion.

Objective To analyze the related risk factors of re-nonunion after primary revision for femoral shaft nonunion subsequent to failed intramedullary nailing. Methods A retrospective study was performed in 61 patients with femoral shaft nonunion subsequent to failed intramedullary nailing from June 2008 to June.All patients were divided into re-nonunion group(22 cases)and non-re-nonunion group (39 cases) according to diagnostic criteria of bone re-nonunion. Univariate analysis was used to analyze 14 factors that may lead to the occurrence of re-nonunion after revision for femoral shaft nonunion subsequent to failed intramedullary nailing including age, gender, body mass index (BMI), smoking, alcohol abuse, injury reason, fracture types, intramedullary nail types, locking screws technology for intramedullary nail, bone nonunion sites, bone nonunion time, pathological types of bone nonunion, primary revision methods and autologous bone graft or not, and multi-factor logistic regression analysis was performed on the factors showing a significant difference. Results Univariate analysis showed significant difference in smoking (χ2= 6.564, P = 0.036), BMI (χ2= 6.783, P = 0.021), bone nonunion sites(χ2=7.316,P=0.011),primary revision methods(χ2=8.069,P=0.003)and autologous bone graft or not(χ 2=6.668,P=0.027).Logistic regression analysis showed that primary revision methods(OR=1.027,95% CI 0.028-0.463,P<0.05)and autologous bone graft or not(OR=1.024,95% CI 0.006-0.363, P < 0.05) were independent risk factors for re-nonunion after revision of femoral shaft nonunion subsequent to failed intramedullary nailing. Conclusions Primary revision methods and autologous bone graft or not are independent risk factors for re-nonunion after revision of femoral shaft nonunion subsequent to failed intramedullary nailing.By strictly controlling the surgical indications and combining with autogenous bone grafting,it is possible to reduce the occurrence of nonunion after primary revision of the femoral shaft nonunion subsequent to failed intramedullary nailing.

BACKGROUND:Lisfranc injury is a concealed or low-energy damage in the athletic population. The optimal treatment strategies for Lisfranc injury in the athletes, especial y for high-level or professional athletes, remain controversial. Improvement and development in treatment for Lisfranc injury are ongoing. OBJECTIVE:To summarize the diagnostic and therapeutic strategies and problems in surgery in Lisfranc injuries in the athletic population. METHODS:A computer-based online search was conducted in PubMed and Web of science databases from June 1909 to June 2014 to screen the relevant articles regarding the diagnostic and therapeutic strategies for Lisfranc injury using the key words“Lisfranc, injury, athletes”. The irrelevant and duplicate articles were excluded, and final y 43 articles were reviewed. RESULTS AND CONCLUSION:With the improvement and development in the therapeutic methods for Lisfranc injury, suture button fixation and bioabsorbable screw technology, as novel treatment strategies, have the potential to help restore and/or preserve stability at the tarsometatarsal joints, to avoid the potential risk for internal fixation irritation or the need for removal of hardware after fixation. However, more multi-center, prospective, randomized control ed clinical trials are required for seeking the optimal treatment for Lisfranc injury. For the athletes with Lisfranc injury, the best treatment option, removal timing of internal fixation devices, and the proper postoperative function exercise performed according the conditions of patients are vital for restoring the professional sports level.

BACKGROUND:Semaphorin7A (Sema7A) is a kind of cel surface protein, which can promote the fusion of osteoclasts and the migration of osteoblasts at the same time, affecting the dynamic balance of the bone. It is speculated that Sema7A siRNA may inhibit osteoblast apoptosis induced by titanium particles. OBJECTIVE:To study the effect of Sema7A on the preosteoblast activity inhibited by titanium particles. METHODS:Mouse MC3T3-E1 preosteoblasts at passages 6 and 7 were divided into four groups: in blank control group, MC3T3-E1 cels were cultured alone; in standard control group, cel were cultured with titanium particles; in experimental groups 1 and 2, the cels were cultured with titanium particles+Sema7A overexpression plasmids and titanium particles+Sema7A siRNA, respectively. Apoptotic rate of MC3T3-E1 cels was detected by flow cytometry; the mRNA expression of bone sialoprotein, osteocalcin and type I colagen was detected by Q-PCR; western blot assay was adopted to detect the protein expression of bone sialoprotein, osteocalcin and type I colagen; alizarin red calcium nodule staining was taken to detect the degree of osteoblast mineralization. RESULTS AND CONCLUSION:The expressions of bone sialoprotein, osteocalcin and type I colagen were decreased in the standard control group and experimental group 1, but these expression were significantly increased in the experimental group 2 compared with the standard control group (P < 0.05). Flow cytometry results suggested that the apoptotic rate of osteoblasts in the experimental group 1 was significantly higher than that in the other groups (P < 0.05), and the apoptotic rate in the experimental group 2 was lower than that in the standard control group (P < 0.05). Alizarin red staining showed that there were no obvious mineralized nodules in the experimental group 1, but mineralized nodules formed in the experimental group 2. In brief, the genetic interference technique that inhibits the activity of Sema7A can interfere the process of mouse MC3T3-E1 preosteoblast differentiation inhibited by titanium particles, and thus provide a feasible way for the clinical treatment of wear particles-induced osteolysis using biotechnology.

Objective To analyze the related risk factors for Lisfranc injury resulting from low energy violence.Methods A retrospective study was performed for 61 cases (35 males,26 females) with low-energy foot injury hospitalized from June 2008 to June 2014.Mean age was 36.7 years (range,16-57 years).Fall injuries were noted in 24 cases,sports injuries in 21 cases,and twist injuries in 16 cases.The cases were divided into Lisfranc injury group(n =23) and non-Lisfranc injury group (n =38) according to the different diagnosis.Univariate analysis and multi-factor logistic regression analysis were used to identify the factors that may lead to the occurrence of Lisfranc injury including age,gender,body mass index,operation history,smoking,alcohol abuse,injury reason,medial depth of the mortise/ second metatarsal length (b/a),lateral depth of the mortise/ second metatarsal length (c/a),first metatarsal-to-talus angle,first intermetatarsal angle,second metatarsal length/foot length(a/g),calcaneal inclination angle and cuboid-navicular overlap/cuboid vertical height (e/e + f).Results Univariate analysis showed between-group differences were significant in age (x2 =7.385,P ＜0.05),injury reason (x2 =8.663,P ＜ 0.05),calcaneal inclination angle (t =3.958,P ＜ 0.05),b/a (t =5.051,P ＜ 0.05) and a/g(t =4.618,P ＜ 0.05).Logistic regression analysis identified b/a(OR =1.036,95 ％ CI 0.018-0.450,P ＜ 0.01) and a/g(OR =1.013,95％ CI 0.005-0.374,P ＜ 0.01) as independent risk factors for low-energy Lisfranc injury.Conclusion Low-energy Lisfranc injury is independently associated with b/a and a/g,and may relate to the decreased medial depth of the mortise and increased foot length.

BACKGROUND:Sema7A is a kind of cel surface protein, which can promote the fusion of osteoclasts and the migration of osteoblast at the same time, affecting the dynamic balance of bone. OBJECTIVE:To investigate whether Sema7A siRNA has ainhibitory effect on the osteoclast activation in the process of osteolysis which induced by titanium particles. METHODS:The precursor osteoclasts with the concentration of 4×109 RESULTS AND CONCLUSION:At 7 days of culture, the expression levels of interleukin-1, interleukin-1β, tumor necrosis factor α, matrix metaloproteinase-9 and the receptor activator of nuclear factor-κB in the positive control, /L were seeded on 96-wel plates containing glass cover slips, and divided into four groups: blank control, positive control, experiment and negative control groups. The cel culture medium was added into the control group. 20 μL un-transfected siRNA supernatant was added into the positive control group. 20 μL transfected Sema7A siRNA supernatant was added into the experiment group. 20 μL transfected control siRNA supernatant was added into the negative control group. The supernatant was obtained through the co-culture between titanium particles solution and monocyte-macrophage cel line RAW264.7of mouse for 24 hours. siRNA was transfected into mononuclear macrophage cel lines RAW264.7 of mice. negative control and experiment groups were higher than those in the control group (P < 0.05). The expression level of each factor in the experiment group was lower than that in the positive control and negative control groups (P < 0.05). At 8 days of culture, the proliferation activity of osteoclasts and the number of positive cels stained by tartrate-resistant acid phosphatase in the positive control, negative control and experiment groups were higher than those in the control group (P < 0.05). The proliferation activity of osteoclasts and the number of positive cels stained by tartrate-resistant acid phosphatase in the experiment group were lower than those in the control and negative groups (P < 0.05). These results demonstrate that Sema7A siRNA has a certain inhibitory effect on the osteoclast activation induced by titanium particles.

BACKGROUND:Bone formation is a dynamic process, and osteoclasts and osteoblasts are involved in this dynamic process. Semaphorins were found first as axonal growth cone guidance molecules, which express in many different tissues and regulate many physiological processes. Recently, Semaphorins are confirmed to play an important role in the regulation of osteoclasts and osteoblasts. OBJECTIVE:To summarize the role of Semaphorins in bone homeostasis. METHODS: A computer-based search of PubMed and Web of Science was performed for articles related to the effect of Semaphorins in regulation of bone metabolism published from June 1993 to January 2014 using the keywords of “semaphorin, sema”. Irrelevant articles or duplicate content articles were excluded, and finaly 48 articles were reviewed. RESULTS AND CONCLUSION:Semaphorins act as a new class of regulatory molecules in the aspect of bone cytobiology. Studies have show semaphorins are actively involved in bone remodeling through some special mechanisms, and semaphorin proteins are crucial for bone homeostasis, which provides a new method and therapeutic target for the treatment of osteoporosis, bone sclerosis, osteolysis adjacent to joint prosthesis and other bone diseases.