目的总结大直径股骨头金属对金属(以下简称大头金对金)人工全髋关节置换术(total hip arthroplasty,THA)后中远期疗效,分析置换失败原因。方法回顾分析2007年3月—2010年5月采用大头金对金THA治疗的159例(183髋)患者临床资料。男109例(...目的总结大直径股骨头金属对金属(以下简称大头金对金)人工全髋关节置换术(total hip arthroplasty,THA)后中远期疗效,分析置换失败原因。方法回顾分析2007年3月—2010年5月采用大头金对金THA治疗的159例(183髋)患者临床资料。男109例(129髋),女50例(54髋);年龄20~78岁,平均50岁。单髋135例,其中左髋69例、右髋66例;双髋24例。初次置换原因:股骨头缺血性坏死74例(93髋),Perthes病1例(1髋),髋关节原发性骨关节炎18例(19髋),髋关节发育不良继发骨关节炎17例(18髋),化脓性髋关节炎治愈后骨关节炎8例(8髋),髋关节创伤性关节炎6例(6髋),股骨颈骨折17例(17髋),强制性脊柱炎髋关节受累8例(11髋),髋关节类风湿性关节炎9例(9髋),成人Still病1例(1髋)。术前Harris评分(45.99±8.07)分,疼痛视觉模拟评分(VAS)为(6.59±0.87)分。结果术后患者切口均Ⅰ期愈合,无手术相关并发症发生。患者均获随访,随访时间1.2~8.2年,平均6.1年。术后15例(17髋)失败,假体5年生存率为91.80%(168/183)。失败原因:炎性假瘤形成4例(4髋),髋臼松动3例(3髋),骨溶解4例(5髋),髋臼松动并炎性假瘤形成3例(3髋),功能失用性表现1例(2髋)。其中9例(11髋)因多种原因未行翻修术;6例(6髋)于初次置换术后1.2~5.4年,平均3.7年行翻修术。末次随访时,VAS评分为(1.72±1.48)分,髋关节Harris评分为(81.37±10.75)分,与术前比较差异均有统计学意义(t=–35.547,P=0.000;t=33.823,P=0.000);其中44髋为优,89髋为良,33髋为可,17髋为差。结论大头金对金THA术后中远期失败率较高,失败原因主要为炎性假瘤形成、髋臼松动和骨溶解。尽快实施翻修手术可有效改善患者功能障碍,提高生活质量。展开更多
The era of metal-on-metal(MoM) total hip arthroplasty has left the orthopaedic community with valuable insights and lessons on periprosthetic tissue reactions to metallic debris. Various terms have been used to descri...The era of metal-on-metal(MoM) total hip arthroplasty has left the orthopaedic community with valuable insights and lessons on periprosthetic tissue reactions to metallic debris. Various terms have been used to describe the tissue reactions. Sometimes the nomenclature can be confusing. We present a review of the concepts introduced by Willert and Semlitsch in 1977,along with further developments made in the understanding of periprosthetic tissue reactions to metallic debris. We propose that periprosthetic tissue reactions be thought of as(1) gross(metallosis, necrosis, cyst formation and pseudotumour);(2) histological(macrophage-dominated, lymphocyte-dominated or mixed);and(3) molecular(expression of inflammatory mediators and cytokines such as interleukin-6 and tumor necrosis factor-alpha). Taper corrosion and modularity are discussed, along with future research directions to elucidate the antigen-presenting pathways and materi-al-specific biomarkers which may allow early detection and intervention in a patient with adverse periprosthetic tissue reactions to metal wear debris.展开更多
BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals w...BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals with echocardiographic measures in TJA patients.METHODS The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium concentrations.Patients underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal concentrations.Age and sex-adjusted linear and logistic regression models were used to examine the association of metal concentrations(exposure)with echocardiographic measures(outcome).RESULTS Higher cobalt concentrations were associated with increased left ventricular end-diastolic volume(estimate 5.09;95%CI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac function.Higher titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%CI:0.70 to 0.06)and cardiac index(estimate 0.08;95%CI,-0.15 to-0.01).CONCLUSION Elevated cobalt and titanium concentrations may be associated with structural and functional cardiac changes in some patients.Longitudinal studies are warranted to better understand the systemic effects of metals in TJA patients.展开更多
The theoretical advantages of metal-on-metal(MOM)bearing couples in total hip arthroplasty(THA) have been recently balanced by concerns regarding adverse local and systemic effects. Higher than anticipated early revis...The theoretical advantages of metal-on-metal(MOM)bearing couples in total hip arthroplasty(THA) have been recently balanced by concerns regarding adverse local and systemic effects. Higher than anticipated early revision rates have been reported by several joint registries. Failed MOM hips present with a spectrum of symptoms and findings and traditional methods of failure must be considered in addition to the failure modes that appear to be unique to the MOM bearing couple. Metal hypersensitivity and soft tissue immune reactions remain incompletely understood and require careful ongoing study. The tools available to evaluate MOM THAs and the indications for revision surgery remain to be defined. Outcomes following revision of MOM hips appear to depend on appropriate evaluation, early identification, and appropriate surgical management.展开更多
[目的]评价全髋关节表面置换术治疗髋关节疾病的近期疗效并探讨其临床体会。[方法]回顾性分析2006年10月～2008年4月行全髋关节表面置换术患者68例81髋,男32例40髋,女36例41髋;年龄24～74岁,平均42.5岁。采用金属对金属表面髋假体(metal...[目的]评价全髋关节表面置换术治疗髋关节疾病的近期疗效并探讨其临床体会。[方法]回顾性分析2006年10月～2008年4月行全髋关节表面置换术患者68例81髋,男32例40髋,女36例41髋;年龄24～74岁,平均42.5岁。采用金属对金属表面髋假体(metal on metal surface arthroplasty,MMSA),随访6～25个月,平均14个月,进行髋关节Harris评分。[结果]本组病例随访期间无1例发生严重并发症。术后髋关节疼痛均明显好转,Harris评分由术前平均36分(30～45分)提高到术后平均93分(84～98分),其中优70髋,良11髋,优良率100%。[结论]全髋关节表面置换术治疗年轻患者和对运动要求较高的老年患者的近期疗效满意,术后髋关节疼痛和髋关节功能明显改善,严格的临床适应证、完善的术前准备、精细的手术操作和对表面髋特性的清晰认识是全髋关节表面置换术成功的关键。展开更多
BACKGROUND This unique presentation of hip swelling is only the seventh reported case of pseudotumor recurrence in a non-metal-on-metal total hip arthroplasty(THA)construct.The constellation of patient symptoms and la...BACKGROUND This unique presentation of hip swelling is only the seventh reported case of pseudotumor recurrence in a non-metal-on-metal total hip arthroplasty(THA)construct.The constellation of patient symptoms and laboratory findings contradict the expected elevated serum metal ion levels associated with the formation of pseudotumor.The presentation,lab trends,and imaging findings contribute to the growing base of knowledge surrounding the effects of corrosion in arthroplasty constructs with stem-neck modularity.CASE SUMMARY A 74-year-old man status post primary THA presented with left hip swelling and elevated serum metal ions five years after implantation of a modular stem-neck prosthesis.The swelling was diagnosed as pseudotumor based on laboratory trends and imaging findings and was treated with revision arthroplasty that completely resolved the initial hip swelling.The patient presented with recurrent hip swelling and recurrent pseudotumor findings on imaging in the same hip four months later.Non-operative management with ultrasound-guided hip aspiration resulted in symptom relief and resolution of the recurrent swelling.After one year of follow-up,the patient had no further recurrences of hip swelling.CONCLUSION This case of post-revision pseudotumor recurrence elucidates attributable patient,surgical,and implant factors with a discussion of diagnostics,management,and prognosis for patients with pseudotumor in non-metal-on-metal arthroplasty constructs.展开更多
目的探讨大直径股骨头金属-金属人工全髋关节置换术(total hip arthroplasty,THA)的中期疗效。方法回顾性分析2009年4月—2010年6月收治并接受大直径金属-金属THA治疗40例(43髋)患者临床资料。其中男18例(20髋),女22例(23髋);年龄20～85...目的探讨大直径股骨头金属-金属人工全髋关节置换术(total hip arthroplasty,THA)的中期疗效。方法回顾性分析2009年4月—2010年6月收治并接受大直径金属-金属THA治疗40例(43髋)患者临床资料。其中男18例(20髋),女22例(23髋);年龄20～85岁,平均55.1岁。单髋37例,双髋3例。股骨头缺血性坏死14例(15髋),原发性骨关节炎6例(7髋),类风湿性关节炎4例(4髋),股骨颈骨折4例(4髋),先天性髋关节发育不良12例(13髋)。术前髋关节Harris评分为(38.51±5.62)分,美国加州大学洛杉矶分校(UCLA)评分为(4.21±1.43)分,疼痛视觉模拟评分(VAS)为(6.78±0.95)分。结果患者均获随访,随访时间6.7～8.3年,平均7.5年。术后切口均Ⅰ期愈合,无神经、血管损伤以及感染、关节脱位等并发症发生。末次随访时,Harris评分为(93.33±3.21)分、UCLA评分为(7.32±1.45)分,与术前比较差异均有统计学意义(t=51.753,P=0.000;t=23.232,P=0.000)。术后3例(3髋)发生大腿疼痛,其中1例出现软组织炎性假瘤。X线片复查示,髋臼外展角及前倾角分别为(46.5±3.2)、(14.8±3.6)°;股骨柄假体初始稳定质量按照Mulliken标准评定,获优39髋、良4髋。随访期间,2髋发生骨溶解,其中1髋继发假体松动行翻修术;其余患者假体无松动、下沉。结论大直径股骨头金属-金属THA治疗髋关节终末疾病中期疗效良好。展开更多
A simple and versatile synthesis method was developed to prepare inorganic multi-metal oxide hollow spheres with tunable compositions. The colloidal nanosheets of layered double hydroxides （LDH） with pre-determined ...A simple and versatile synthesis method was developed to prepare inorganic multi-metal oxide hollow spheres with tunable compositions. The colloidal nanosheets of layered double hydroxides （LDH） with pre-determined compositions were used as precursors for multi-metal oxides and carbon spheres （CSs） prepared by hydrothermal carbonization of glucose were used as hard templates. Electrostatic force drove the positively charged LDH nanosheets to be anchored by the negatively charged CSs once they were mixed, leading to the formation of core-shell structures. Finally, multi-metal oxides with hollow spherical structures were obtained by calcination, These hollow spheres were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, trans- mission electron microscope （TEM） and inductively coupled plasma （ICP）. Results revealed that the as-prepared oxide hollow spheres could exactly inherit the metal-to-metal ratios of initial LDH precursors, which provided an effective way to control the compositions of oxide shells. This strategy was suitable for preparation of a series of oxide hollow spheres from binary to multi-component ones, including MgO/Ak2O3, MgO/Fe3O4, NiO/Al2O3, and ZnO/NiO/Al2O3.展开更多
Background: There is much interest regarding metal-on-metal implants in medical and general media. Much of this has been regarding failure of specific implant systems and metal ion toxicity. We present our early mid-t...Background: There is much interest regarding metal-on-metal implants in medical and general media. Much of this has been regarding failure of specific implant systems and metal ion toxicity. We present our early mid-term experience of the ADEPT metal-on-metal system which has both modular and non-modular hip options. Methods: Functional assessment, blood metal ion quantification, and radiographic analysis were performed for the modular and non-modular ADEPT variants. Fifty implants were implanted with a mean follow up time of 28 months. Unpaired t-tests were used to compare modular and resurfacing groups, standardised hip scores were used to compare function to conventional total hip arthroplasty. Results: Metal ion levels were significantly higher in modular prostheses compared to resurfacing implants, but not at “harmful” levels (as determined by a previous metal-on-metal implant recall). Functional outcomes were excellent and revision rates were lower than expected. Conclusions: At our institution we have good outcomes with the ADEPT hip prosthesis. Though patient selection and implant position are crucial, poor performance of metal-on-metal hip replacements is implant specific.展开更多
Squeaking is a well-recognized complication for hardon-hard bearings.The nature of squeaking is not yet completely understood however it is considered a multifactorial phenomenon.Patient,implant,and surgical factors p...Squeaking is a well-recognized complication for hardon-hard bearings.The nature of squeaking is not yet completely understood however it is considered a multifactorial phenomenon.Patient,implant,and surgical factors play a role in squeaking.It is believed that mechanisms damaging the fluid film lubrication in which these bearings function optimally have a critical role.Such mechanisms include edge loading,stripe wear,impingement,third body particles and ceramic fracture.The resonance of metallic parts can produce noise in the human audible range hence the implant metallurgic composition and design may play a role.Implant positioning can facilitate impingement and edge loading enhancing the occurrence of squeaking.The recent introduction of large heads(> 36 mm) 4th generation ceramic-on-ceramic bearing may accentuate the conditions facilitating noise formation; however the current literature is insufficient.Clinically,squeaking may manifest in extreme hip positions or during normal gait cycle however it is rarely associated with pain.Evaluations of patients with squeaking include clinical and radiographic assessments.Computer tomography is recommended as it can better reveal ceramic breakage and implant malposition.The treatments for most squeaking patients include reassurance and activity modification.However for some,noise can be a problem,requiring further surgical intervention.In the occurrence of ceramic fracture,implant failure,extreme components malposition,instability and impingement,surgery should be advised.This review will aim to discuss the current literature regarding squeaking.展开更多
文摘目的总结大直径股骨头金属对金属(以下简称大头金对金)人工全髋关节置换术(total hip arthroplasty,THA)后中远期疗效,分析置换失败原因。方法回顾分析2007年3月—2010年5月采用大头金对金THA治疗的159例(183髋)患者临床资料。男109例(129髋),女50例(54髋);年龄20~78岁,平均50岁。单髋135例,其中左髋69例、右髋66例;双髋24例。初次置换原因:股骨头缺血性坏死74例(93髋),Perthes病1例(1髋),髋关节原发性骨关节炎18例(19髋),髋关节发育不良继发骨关节炎17例(18髋),化脓性髋关节炎治愈后骨关节炎8例(8髋),髋关节创伤性关节炎6例(6髋),股骨颈骨折17例(17髋),强制性脊柱炎髋关节受累8例(11髋),髋关节类风湿性关节炎9例(9髋),成人Still病1例(1髋)。术前Harris评分(45.99±8.07)分,疼痛视觉模拟评分(VAS)为(6.59±0.87)分。结果术后患者切口均Ⅰ期愈合,无手术相关并发症发生。患者均获随访,随访时间1.2~8.2年,平均6.1年。术后15例(17髋)失败,假体5年生存率为91.80%(168/183)。失败原因:炎性假瘤形成4例(4髋),髋臼松动3例(3髋),骨溶解4例(5髋),髋臼松动并炎性假瘤形成3例(3髋),功能失用性表现1例(2髋)。其中9例(11髋)因多种原因未行翻修术;6例(6髋)于初次置换术后1.2~5.4年,平均3.7年行翻修术。末次随访时,VAS评分为(1.72±1.48)分,髋关节Harris评分为(81.37±10.75)分,与术前比较差异均有统计学意义(t=–35.547,P=0.000;t=33.823,P=0.000);其中44髋为优,89髋为良,33髋为可,17髋为差。结论大头金对金THA术后中远期失败率较高,失败原因主要为炎性假瘤形成、髋臼松动和骨溶解。尽快实施翻修手术可有效改善患者功能障碍,提高生活质量。
文摘The era of metal-on-metal(MoM) total hip arthroplasty has left the orthopaedic community with valuable insights and lessons on periprosthetic tissue reactions to metallic debris. Various terms have been used to describe the tissue reactions. Sometimes the nomenclature can be confusing. We present a review of the concepts introduced by Willert and Semlitsch in 1977,along with further developments made in the understanding of periprosthetic tissue reactions to metallic debris. We propose that periprosthetic tissue reactions be thought of as(1) gross(metallosis, necrosis, cyst formation and pseudotumour);(2) histological(macrophage-dominated, lymphocyte-dominated or mixed);and(3) molecular(expression of inflammatory mediators and cytokines such as interleukin-6 and tumor necrosis factor-alpha). Taper corrosion and modularity are discussed, along with future research directions to elucidate the antigen-presenting pathways and materi-al-specific biomarkers which may allow early detection and intervention in a patient with adverse periprosthetic tissue reactions to metal wear debris.
基金Supported by The National Institutes of Health,No.R01HL147155 and No.R01AG060920.
文摘BACKGROUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)patients.AIM To determine the association of commonly used implant metals with echocardiographic measures in TJA patients.METHODS The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium concentrations.Patients underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal concentrations.Age and sex-adjusted linear and logistic regression models were used to examine the association of metal concentrations(exposure)with echocardiographic measures(outcome).RESULTS Higher cobalt concentrations were associated with increased left ventricular end-diastolic volume(estimate 5.09;95%CI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac function.Higher titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%CI:0.70 to 0.06)and cardiac index(estimate 0.08;95%CI,-0.15 to-0.01).CONCLUSION Elevated cobalt and titanium concentrations may be associated with structural and functional cardiac changes in some patients.Longitudinal studies are warranted to better understand the systemic effects of metals in TJA patients.
文摘The theoretical advantages of metal-on-metal(MOM)bearing couples in total hip arthroplasty(THA) have been recently balanced by concerns regarding adverse local and systemic effects. Higher than anticipated early revision rates have been reported by several joint registries. Failed MOM hips present with a spectrum of symptoms and findings and traditional methods of failure must be considered in addition to the failure modes that appear to be unique to the MOM bearing couple. Metal hypersensitivity and soft tissue immune reactions remain incompletely understood and require careful ongoing study. The tools available to evaluate MOM THAs and the indications for revision surgery remain to be defined. Outcomes following revision of MOM hips appear to depend on appropriate evaluation, early identification, and appropriate surgical management.
文摘[目的]评价全髋关节表面置换术治疗髋关节疾病的近期疗效并探讨其临床体会。[方法]回顾性分析2006年10月～2008年4月行全髋关节表面置换术患者68例81髋,男32例40髋,女36例41髋;年龄24～74岁,平均42.5岁。采用金属对金属表面髋假体(metal on metal surface arthroplasty,MMSA),随访6～25个月,平均14个月,进行髋关节Harris评分。[结果]本组病例随访期间无1例发生严重并发症。术后髋关节疼痛均明显好转,Harris评分由术前平均36分(30～45分)提高到术后平均93分(84～98分),其中优70髋,良11髋,优良率100%。[结论]全髋关节表面置换术治疗年轻患者和对运动要求较高的老年患者的近期疗效满意,术后髋关节疼痛和髋关节功能明显改善,严格的临床适应证、完善的术前准备、精细的手术操作和对表面髋特性的清晰认识是全髋关节表面置换术成功的关键。
文摘BACKGROUND This unique presentation of hip swelling is only the seventh reported case of pseudotumor recurrence in a non-metal-on-metal total hip arthroplasty(THA)construct.The constellation of patient symptoms and laboratory findings contradict the expected elevated serum metal ion levels associated with the formation of pseudotumor.The presentation,lab trends,and imaging findings contribute to the growing base of knowledge surrounding the effects of corrosion in arthroplasty constructs with stem-neck modularity.CASE SUMMARY A 74-year-old man status post primary THA presented with left hip swelling and elevated serum metal ions five years after implantation of a modular stem-neck prosthesis.The swelling was diagnosed as pseudotumor based on laboratory trends and imaging findings and was treated with revision arthroplasty that completely resolved the initial hip swelling.The patient presented with recurrent hip swelling and recurrent pseudotumor findings on imaging in the same hip four months later.Non-operative management with ultrasound-guided hip aspiration resulted in symptom relief and resolution of the recurrent swelling.After one year of follow-up,the patient had no further recurrences of hip swelling.CONCLUSION This case of post-revision pseudotumor recurrence elucidates attributable patient,surgical,and implant factors with a discussion of diagnostics,management,and prognosis for patients with pseudotumor in non-metal-on-metal arthroplasty constructs.
文摘目的探讨大直径股骨头金属-金属人工全髋关节置换术(total hip arthroplasty,THA)的中期疗效。方法回顾性分析2009年4月—2010年6月收治并接受大直径金属-金属THA治疗40例(43髋)患者临床资料。其中男18例(20髋),女22例(23髋);年龄20～85岁,平均55.1岁。单髋37例,双髋3例。股骨头缺血性坏死14例(15髋),原发性骨关节炎6例(7髋),类风湿性关节炎4例(4髋),股骨颈骨折4例(4髋),先天性髋关节发育不良12例(13髋)。术前髋关节Harris评分为(38.51±5.62)分,美国加州大学洛杉矶分校(UCLA)评分为(4.21±1.43)分,疼痛视觉模拟评分(VAS)为(6.78±0.95)分。结果患者均获随访,随访时间6.7～8.3年,平均7.5年。术后切口均Ⅰ期愈合,无神经、血管损伤以及感染、关节脱位等并发症发生。末次随访时,Harris评分为(93.33±3.21)分、UCLA评分为(7.32±1.45)分,与术前比较差异均有统计学意义(t=51.753,P=0.000;t=23.232,P=0.000)。术后3例(3髋)发生大腿疼痛,其中1例出现软组织炎性假瘤。X线片复查示,髋臼外展角及前倾角分别为(46.5±3.2)、(14.8±3.6)°;股骨柄假体初始稳定质量按照Mulliken标准评定,获优39髋、良4髋。随访期间,2髋发生骨溶解,其中1髋继发假体松动行翻修术;其余患者假体无松动、下沉。结论大直径股骨头金属-金属THA治疗髋关节终末疾病中期疗效良好。
文摘A simple and versatile synthesis method was developed to prepare inorganic multi-metal oxide hollow spheres with tunable compositions. The colloidal nanosheets of layered double hydroxides （LDH） with pre-determined compositions were used as precursors for multi-metal oxides and carbon spheres （CSs） prepared by hydrothermal carbonization of glucose were used as hard templates. Electrostatic force drove the positively charged LDH nanosheets to be anchored by the negatively charged CSs once they were mixed, leading to the formation of core-shell structures. Finally, multi-metal oxides with hollow spherical structures were obtained by calcination, These hollow spheres were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, trans- mission electron microscope （TEM） and inductively coupled plasma （ICP）. Results revealed that the as-prepared oxide hollow spheres could exactly inherit the metal-to-metal ratios of initial LDH precursors, which provided an effective way to control the compositions of oxide shells. This strategy was suitable for preparation of a series of oxide hollow spheres from binary to multi-component ones, including MgO/Ak2O3, MgO/Fe3O4, NiO/Al2O3, and ZnO/NiO/Al2O3.
文摘Background: There is much interest regarding metal-on-metal implants in medical and general media. Much of this has been regarding failure of specific implant systems and metal ion toxicity. We present our early mid-term experience of the ADEPT metal-on-metal system which has both modular and non-modular hip options. Methods: Functional assessment, blood metal ion quantification, and radiographic analysis were performed for the modular and non-modular ADEPT variants. Fifty implants were implanted with a mean follow up time of 28 months. Unpaired t-tests were used to compare modular and resurfacing groups, standardised hip scores were used to compare function to conventional total hip arthroplasty. Results: Metal ion levels were significantly higher in modular prostheses compared to resurfacing implants, but not at “harmful” levels (as determined by a previous metal-on-metal implant recall). Functional outcomes were excellent and revision rates were lower than expected. Conclusions: At our institution we have good outcomes with the ADEPT hip prosthesis. Though patient selection and implant position are crucial, poor performance of metal-on-metal hip replacements is implant specific.
文摘Squeaking is a well-recognized complication for hardon-hard bearings.The nature of squeaking is not yet completely understood however it is considered a multifactorial phenomenon.Patient,implant,and surgical factors play a role in squeaking.It is believed that mechanisms damaging the fluid film lubrication in which these bearings function optimally have a critical role.Such mechanisms include edge loading,stripe wear,impingement,third body particles and ceramic fracture.The resonance of metallic parts can produce noise in the human audible range hence the implant metallurgic composition and design may play a role.Implant positioning can facilitate impingement and edge loading enhancing the occurrence of squeaking.The recent introduction of large heads(> 36 mm) 4th generation ceramic-on-ceramic bearing may accentuate the conditions facilitating noise formation; however the current literature is insufficient.Clinically,squeaking may manifest in extreme hip positions or during normal gait cycle however it is rarely associated with pain.Evaluations of patients with squeaking include clinical and radiographic assessments.Computer tomography is recommended as it can better reveal ceramic breakage and implant malposition.The treatments for most squeaking patients include reassurance and activity modification.However for some,noise can be a problem,requiring further surgical intervention.In the occurrence of ceramic fracture,implant failure,extreme components malposition,instability and impingement,surgery should be advised.This review will aim to discuss the current literature regarding squeaking.
