屈曲挛缩畸形膝关节置换的软组织平衡

目的：探讨屈曲挛缩畸形的膝关节行关节置换的方法,重点关注术中膝关节周围软组织平衡的方法。技巧及术后疗效。方法：自2010年6月～2012年6月共收治晚期膝关节疾病合并屈曲挛缩畸形患者156例,213膝,采取人工膝关节置换进行治疗,分别记录术前术后膝关节畸形程度,HSS评分,活动范围。并进行比较。本组病例平均年龄60．2岁（44～81岁）,女92例136膝,男64例77膝。膝骨性关节炎85例,类风湿性关节炎58例,创伤性关节炎13例。膝关节活动范围平均52．6°（33．5°～94．1°）。本组病例轻度屈曲畸形：83例117膝,中度屈曲畸形：58例76膝,重度屈曲畸形：15例20膝。平均屈曲畸形程度：45．8°。每例患者均进行术前及术后1年HSS评分进行疗效评价。结果：所有病例获得随访,屈曲挛缩畸形均得到改善,膝关节HSS评分由术前20．7分提高到术后平均73．6分。膝关节活动范围术前平均52．6°提高到术后平均92．7°。结论：晚期膝关节病所致的屈曲挛缩畸形的膝关节行膝关节置换术,除了在术中注意准确截骨外,应着重注意软组织松解,调整力线。     

选择性软组织松解技术在重度膝外翻畸形全膝关节置换术中的应用

目的探讨全膝关节置换（TKA）术中对重度膝外翻畸形软组织平衡的处理方法。方法自2003-07—2009-12对29例（32膝）膝外翻畸形（胫股角〉15°）的患者均采用术中局部选择性松解技术实现软组织平衡。分别于术前和术后1、3、6、12、24个月摄膝关节正位X线片、测定膝关节活动度（ROM）和进行HSS评分,评估术后临床疗效。结果 21例（24膝）获得随访,随访时间9~47个月,平均27.2个月。X线片显示假体位置良好,未见明显松动和下沉迹象。术前关节活动度平均（103.5±8.7）°,末次随访时平均（123.3±6.3）°。术前HSS评分平均（62.5±8.6）分,末次随访时平均（86.9±4.6）分。术后均未出现严重并发症。结论局部选择性软组织松解技术在处理重度膝外翻畸形软组织失衡方面疗效确切,该技术损伤小、安全简便,是TKA术中矫正重度外翻畸形较理想的方法。     

初次人工全膝关节表面置换术治疗膝关节骨关节病108例的疗效观察

[目的]探讨初次人工全膝关节表面置换术(total knee arthroplasty,TKA)治疗膝关节病的临床疗效。[方法]对108例130个膝关节行TKA,男50例(60膝),女58例(70膝);年龄47～87岁,平均71.5岁,术前诊断骨性关节炎62例(70膝),类风湿性关节炎37例(51膝),创伤性关节炎4例,滑膜软骨瘤病2例,色素沉着绒毛结节性滑膜炎2例,陈旧关节结核1例,采用后方稳定假体80例(92膝),后交叉韧带保留假体28例(38膝)。[结果]108例患者均获随访,时间24～84个月,平均50.3个月。患者术后在疼痛、功能、活动度方面改善明显,采用HSS评分系统进行评分,由术前平均48.4分提高到89.3分。术后130个膝关节平均活动度为102°,126个膝关节术后力线正常,3例残留6°～8°内翻,1例后遗15°外翻畸形,手术优良率90.5%。[结论]TKA对治疗严重膝关节病效果满意,术中正确的选择切口,注意假体软组织平衡,精确截骨,注重术中髌骨轨迹的纠正是手术成功的关键。     

类风湿性僵硬膝人工膝关节置换疗效分析

目的:探讨类风湿性僵硬膝人工膝关节置换的策略及疗效。方法:对16例因类风湿关节炎导致僵硬膝并采用人工膝关节置换术治疗的患者进行回顾性分析。结果:15例患者获得12~26个月随访,平均(18.13±4.49)个月。住院期间未出现感染、皮缘坏死、静脉血栓、肺脑栓塞等并发症;术后3个月均可弃拐行走,生活自理;术前膝关节活动度31.67°±11.41°,HSS评分(20.73±7.10)分;术后随访12个月膝关节活动度102.20°±5.92°,HSS评分(77.20±4.41)分;随访12个月,在关节活动度、HSS评分方面较术前明显改善,差异有统计学意义(P0.05)。结论:类风湿性僵硬膝患者,人工膝关节置换能有效改善关节活动功能,改善HSS评分,提高生活质量,近期随访效果可。     

双侧髋、膝四关节置换治疗重度晚期炎性关节病的临床疗效

目的探讨双侧髋、膝四关节置换在治疗重度晚期炎性关节病变中的应用及其临床疗效分析。方法回顾分析2008年9月-2015年9月,采用双侧髋、膝四关节置换并获完整随访的31例炎性关节病患者临床资料。男22例,女9例;发病年龄5~28岁,平均14岁;首次入院时年龄20~41岁,平均30岁。病因:类风湿性关节炎15例,强直性脊柱炎16例。完全卧床23例,扶双拐短距离行走6例,无需辅助短距离行走2例。下肢髋、膝四关节均融合11例,3个关节融合2例,2个关节融合6例,单髋关节融合1例,无关节融合11例。术前髋关节屈伸活动度为(17.82±28.18)°、膝关节屈伸活动度为(26.45±30.18)°;髋关节功能Harris评分为(29.64±11.58)分、膝关节功能美国特种外科医院(HSS)评分为(27.07±11.04)分。观察术后患者髋、膝关节屈伸活动度,采用Harris评分以及HSS评分评价关节功能。按照病因以及术前关节是否融合进行分组比较。结果患者一期四关节置换1例,二期置换22例,三期置换7例,四期置换1例。总手术时间为325~776 min,手术总失血量为900~3 900 m L,围手术期总输血量为2 220~8 070 m L,总住院时间为21~65 d。31例患者随访时间12~94个月,平均51个月。末次随访时,髋、膝关节屈伸活动度以及Harris评分、HSS评分均较术前显著改善(P0.05)。患者主观满意度评定,十分满意16例,一般满意10例,不满意5例。术后2例(3膝)出现假体周围感染,3例(6膝)出现关节僵直,1例单膝关节不稳定,2例双下肢长度相差2 cm;1例单膝存在约10°屈曲畸形。末次随访时,强直性脊柱炎组与风湿性关节炎组比较髋、膝关节屈伸活动度及功能评分,差异均无统计学意义(P0.05)。末次随访时,各融合组患者髋、膝关节活动度均低于对应的未融合组,比较差异有统计学意义(P0.05);Harris评分和HSS评分明显低于对应的未融合组,但差异无统计学意义(P0.05)。结论双侧髋、膝四关节置换是一种矫正因炎性关节病引起的双下肢关节畸形、缓解疼痛、改善关节功能以及提高生活质量的有效治疗手段,术后膝关节晚期假体周围感染以及关节僵直是影响手术疗效的重要并发症。     

膝关节表面置换术治疗重度膝骨关节炎疗效观察

目的:探讨膝关节表面置换术治疗重度膝骨关节炎的临床疗效。方法:选取行膝关节表面置换术的膝骨关节炎患者186例(211膝),术后1个月、3个月、6个月、1年分别随访1次,以后每年复查1次,并选取术前和术后6个月的评定结果进行比较分析。结果:所有患者均获得随访,随访时间为49~78个月,平均(60.8±12.2)个月,186例患者关节活动度(ROM)及随访的影像学结果均良好,假体无松动,假体分区部位未见透亮区及医学骨水泥断裂带。患者术前疼痛评分(78.31±9.62)分及术后6个月疼痛评分(12.65±4.35)分,术前HSS评分(22.30±6.78)分及术后6个月HSS评分(89.83±4.80)分,术前ROM评分(78.62±14.5)分及术后6个月ROM评分(116.5±15.79)分,3者进行比较,差异均有统计学意义(P=0.0000)。术后患者膝关节功能几乎接近正常,畸形得到了纠正,除10例患者(12膝)有轻微疼痛外,余患者疼痛消失。结论:膝关节表面置换术治疗重度膝骨关节炎疗效突出。     

3D打印个体化截骨模板在重度膝关节炎并下肢畸形TKA术中的应用

目的评估3D打印个体化截骨模板在重度膝关节炎合并下肢关节外畸形全膝关节置换(TKA)术中应用的效果。方法回顾性分析自2016-09—2017-09行TKA治疗的6例(8膝)重度膝关节炎并下肢关节外畸形,术中采用3D打印个体化截骨模板辅助截骨。结果 6例均获得随访,随访时间平均6.2(3~10)个月。术后X线片显示假体型号及安装位置正确,下肢力线恢复良好,随访期间无明显假体松动及下沉。末次随访时膝关节活动度为(115.9±13.6)°,股胫角为(4.5±3.4)°,膝关节功能HSS评分为(86.5±12.5)分,均较术前明显改善,差异有统计学意义(P0.05)。结论重度膝关节炎并下肢关节外畸形TKA术中使用3D打印个体化截骨模板截骨可获得较好的假体位置和下肢力线,而且简化了手术步骤,取得了较好的早期临床疗效。     

旋转铰链膝假体在全膝关节置换翻修术后的临床效果

目的探讨使用旋转铰链膝假体进行全膝关节置换(TKA)术后翻修的临床效果。方法回顾性分析2008年10月至2013年5月,广东省人民医院骨科行人工TKA术后翻修且进行随访的重度膝关节畸形患者,其中采用旋转铰链型膝关节假体为10例(10膝)。收治的10例(10膝)TKA术后因假体松动或膝关节感染而需行全膝关节翻修的患者,采用一期翻修或一期清创加自制含抗生素骨水泥植入,可旋转绞链膝假体二期翻修方法治疗。术后进行随访并采用膝关节协会评分(HSS)及膝关节活动度评估膝关节功能。结果全部病例获得2~57个月随访,平均随访时间29个月。10例膝关节全部治愈,无下肢深静脉血栓及肺部感染等并发症。患者膝关节协会评分由术前37分增加至85分,膝关节活动度由术前65°增加至93°。结论在本研究中使用旋转铰链膝假体进行TKA术后翻修,效果确切,患者膝关节功能恢复满意。     

髁限制性假体置换治疗膝骨关节炎

目的 探讨髁限制性假体(LCCK假体)置换治疗膝骨关节炎的疗效。方法 采用LCCK假体置换治疗40例膝骨关节炎患者。记录手术情况以及术后膝关节活动度。采用膝关节HSS评分评价膝关节功能改善情况。结果 患者均获得随访，时间12～60个月。手术时间75～120 min,总出血量110～400 ml。术后X线片显示膝关节力线均明显改善，畸形完全矫正。膝关节HSS评分：由术前23～56(47.11±5.70)分提高到术后1周75～90(84.79±4.70)分(P<0.05)。膝关节活动度：34例术后1周屈曲可达130°、伸直0°;6例类风湿关节炎患者术后1个月膝关节屈曲仅达90°、伸直0°。末次随访时，患者均可独自正常步态行走。结论 LCCK假体置换治疗膝骨关节炎，能有效缓解患者症状，改善膝关节功能，维持膝关节的稳定。     

人工膝关节置换治疗膝外翻畸形的疗效

目的探讨全膝关节置换治疗膝关节外翻畸形的技术方法和临床效果。方法 2006年2月至2010年4月收治12例12膝外翻畸形患者,8例骨关节炎和4例类风湿性关节炎,应用人工全膝关节置换手术治疗。根据X线片比较术前和术后膝外翻角度,应用HSS膝关节评分系统进行临床效果评价。结果术后切口均一期愈合,无感染,无腓总神经麻痹发生;随访6~34个月,平均19个月;术前膝外翻角度13°~35°,平均(19.8±3.3)°,术后膝外翻角度4.9°~9.5°,平均(6.4±1.4)°,与术前比较差异有统计学意义(P0.05);术前HSS评分为31~63分,平均(38.0±2.7)分,术后末次随访膝关节HSS评分为78~89分,平均(84.0±2.9)分,与术前比较差异有统计学意义(P0.05)。结论人工全膝关节置换是膝关节炎合并外翻畸形的有效治疗方法。     

Results of total knee arthroplasty in patients with gonarthrosis resulting from the delayed diagnosis of PVNS: a case series

Pigmented villonodular synovitis (PVNS) is a benign tumor that affects synovial lined joints, tendon sheaths and bursae. It is most commonly seen in one knee joint. The recommended treatment is total synovectomy, while radiotherapy can be used as adjuvant therapy for patients at risk for recurrence. The aim of our study was to show that the devastating effects of inactive diffuse PVNS may not be recognized for years and to evaluate the efficiency of aggressive total synovectomy on patients with PVNS during a follow-up period of 5 years. In the present study, 5 knees of four patients who had been previously followed due to gonarthrosis and diagnosed with PVNS during total knee arthroplasty (TKA) were followed and evaluated for a mean duration of 68 months. Mean age of the patients was 61.2 (52–66). All patients were women. One patient had right knee involvement, two had left knee involvement, and one had both knees involved. All patients had diffuse PVNS. Total synovectomy was performed in all patients in addition to TKA. During the follow-up, recurrence was not seen in any of the patients and prosthesis loosening was not detected. The aim of the present study was to evaluate the effectiveness of total synovectomy over the 5 years following the operation and to show that the devastating effects of inactive PVNS may sometimes be overlooked for years before being recognized during the treatment of the gonarthrosis that develops due to the disease. Although the disease is generally monoarticular, the study also presents a patient with bilateral PVNS.     

人工全膝关节置换术治疗终末期膝关节病变合并膝外翻畸形的手术技巧及临床疗效评价

目的探讨对终末期膝关节病变合并膝外翻畸形患者行经髌旁内侧入路人工全膝关节置换(total kneearthroplasty,TKA)时膝外翻畸形矫正方法及临床疗效。方法 1998年11月-2010年10月,收治64例72膝合并膝外翻畸形的终末期膝关节病变患者。男18例,女46例;年龄23～82岁,平均62.5岁。骨关节炎44例49膝,类风湿性关节炎17例20膝,血友病性关节炎2例2膝,创伤性关节炎1例1膝。双膝8例,单膝56例。膝关节屈伸活动度为(82.2±28.7)°,X线片测量股胫角为(18.0±5.8)°。膝关节学会评分系统(KSS)临床评分为(31.2±10.1)分,功能评分(37.3±9.0)分。根据Krackow膝外翻分型标准:Ⅰ型65膝,Ⅱ型7膝。手术经髌旁内侧入路,采用常规方法行股骨及胫骨截骨,Ranawat技术进行软组织松解。6例7膝采用保留后交叉韧带型假体,54例60膝采用后稳定型假体,4例5膝采用髁限制型假体。结果术后患者切口均Ⅰ期愈合。1例血友病性关节炎合并严重膝外翻畸形(股胫角41°)、屈曲挛缩20°的患者术后出现腓总神经麻痹,经保守治疗1年后神经功能恢复。1例术后2年发生深部感染,行二期翻修术后治愈。患者术后均获随访,随访时间1～13年,平均4.9年。末次随访时X线片示股胫角为(7.0±2.5)°,与术前比较差异有统计学意义(t=15.502,P=0.000)。KSS临床评分为(83.0±6.6)分,功能评分(85.1±10.5)分,膝关节屈伸活动度为(106.1±17.0)°,与术前比较差异均有统计学意义(P0.05)。5例遗留12～15°膝外翻畸形,但患膝关节功能良好。结论通过恰当的术中截骨和软组织平衡,采用经髌旁内侧入路TKA治疗合并膝外翻畸形的终末期膝关节病变可有效改善膝外翻畸形和恢复关节功能,临床疗效满意。     

Unicompartmental knee arthroplasty for medial gonarthrosis: 5 to 9 years follow-up evaluation of 77 knees

A total of 77 knees in 60 consecutive patients were operated on for medial gonarthrosis using a cemented porous coated anatomical (PCA) unicompartmental knee arthroplasty. Their average age was 71.3 years; 11 were men and 49 women. Clinically, the results in 67 knees were rated as being good to excellent, with mean preoperative and postoperative flexion of 123 and 122 deg, respectively. No deep infections or deep venous thrombosis occurred, but there was one dislocation of the femoral component. Overall clinical and radiographic results were satisfactory in 88% at 7.0 years’ follow-up. Kaplan-Meier survivorship analysis indicated that the failure rate of unicompartmental knee arthroplasty was 12% at average follow-up. In patients aged 70 years or more, unicompartmental knee arthroplasty for medial gonarthrosis should be considered an excellent alternative to high tibial osteotomy. Received: 4 November 1996     

Comparison of proprioception in arthritic and age-matched normal knees

BACKGROUND: Proprioception--one's ability to sense joint position and joint motion--is affected by factors such as age, muscle fatigue, and osteoarthritis. Most proprioception studies have focused on young active subjects or on recipients of total knee replacements. Few have involved a population with arthritic knees prior to total knee replacement or persons similar in age to patients with advanced knee arthritis who are to have total knee arthroplasty. The purpose of the present study was to determine (1) if proprioception in arthritic knees differs from proprioception in nonarthritic, age-matched, normal knees; (2) if, when proprioception in one knee is reduced by the presence of advanced gonarthrosis, it also is reduced in the contralateral knee irrespective of the presence of arthritis; and (3) if a person's grade of arthritis is associated with his or her level of proprioception. METHODS: This study compared the proprioception levels of a group of 117 patients who were scheduled for total knee arthroplasty because of severe arthritis (mean age, 67.9 years) with those of a control group of forty patients who were recruited from a hospital-based cardiac rehabilitation program and did not have knee arthritis (mean age, 68.3 years). We used a customized Biodex System 2 Multi-Joint Testing and Rehabilitation System to compare proprioception (the threshold to detection of passive motion) between the two groups. RESULTS: Middle-aged and elderly persons with advanced knee arthritis were significantly less able to detect passive motion of the knee than were middle-aged and elderly persons without knee arthritis. Patients who had arthritis in only one knee had a reduced ability to detect passive motion of both knees. There was no significant association between the radiographic severity of arthritis and the threshold to detection of passive motion in patients with advanced knee arthritis. CONCLUSIONS: Knee proprioception in middle-aged and elderly persons with advanced knee arthritis is reduced in comparison with that in middle-aged and elderly persons without arthritis. Such loss of proprioception is independent of the severity of knee arthritis and may foretell the development of arthritis. When a patient has reduced proprioception with regard to one knee affected by arthritis, he or she also has reduced proprioception with regard to the contralateral knee, independent of the presence or severity of degenerative arthritis. When an investigator is evaluating changes in proprioception after knee arthroplasty, it is best to compare the knee with the patient's untreated knee rather than with age-matched controls.     

髌股关节置换术治疗严重髌股关节炎的中远期疗效

目的 探讨髌股关节置换术治疗单纯髌股关节炎的临床意义及中远期疗效.方法 1991年1月至1999年7月,应用自行研制的人工髌股关节假体(Y-L-Q型)行髌股关节置换术治疗严重的单纯髌股关节炎并获得随访患者39例48膝,男6例6膝,女33例42膝;年龄38～68岁,平均54.4岁.常规于术后3个月、半年、1年及之后每年门诊随访,摄膝关节正侧位、负重位及髌骨轴位X线片,检查关节活动度,询问患者症状,根据自行制定的疗效评价标准进行评价.结果 随访时间8～16年,平均12.7年.末次随访时髌股关节置换的疗效为优29膝、良12膝、可2膝、差5膝,优良率为85.4%.随访期间无假体松动或断裂,无髌骨骨折.3例5膝(10.4%)因病情持续进展而行全膝关节置换术,两次手术的间隔时间为7～12年,平均9.3年.结论 应用自行设计的人工髌股关节假体(Y-L-Q型)行髌股关节置换术是治疗单纯髌股关节炎的一种简单有效的方法,能改善髌前痛症状,推迟全膝关节置换术时间.提高假体生存率的关键是适应证的准确选择和熟练的手术操作.     

Total knee arthroplasty in neuropathic arthropathy

We describe the results of total knee arthroplasty (TKA) undertaken for severe, neurosyphilitic Charcot arthropathy in ten patients (19 knees). A cemented condylar, constrained prosthesis was implanted in all but two knees. The mean follow-up was 5.2 years (5 to 6). The mean knee score before operation was 36.5 points (30 to 42) which improved to 76 points (58 to 90) after operation as judged by the Hospital for Special Surgery score. At final follow-up three knees (16%) had aseptic loosening which required salvage by an arthrodesis, six (31%) were functioning poorly and ten (53%) were satisfactory. We conclude that although Charcot arthropathy is not an absolute contraindication to total knee replacement, there is a high incidence of serious complications.     

Simultaneous revision and contralateral primary total knee arthroplasty

BACKGROUND: There is controversy regarding whether simultaneous or staged bilateral total knee arthroplasty should be performed in patients with bilateral gonarthrosis. In addition, revision total knee arthroplasties have been less successful than primary arthroplasties. The purpose of this study was to evaluate the results of simultaneous revision and contralateral primary total knee arthroplasties performed during the same setting. METHODS: The study cohort included 150 knees in seventy-five patients who had undergone revision arthroplasty because of aseptic failure of a total knee arthroplasty and a contralateral primary arthroplasty for severe gonarthrosis under the same anesthetic. The study group was compared with a control group of sixty patients who had severe arthritis in one knee and had undergone unilateral revision total knee arthroplasty on the contralateral side. The duration of follow-up averaged five years in the group treated with the simultaneous arthroplasties and eight years in the control group. Clinical and radiographic results were evaluated with the Knee Society rating system. RESULTS: In the study group, the average knee score improved by 48 points on the side of the primary arthroplasty and by 37 points on the side of the revision. At the last follow-up visit, most (sixty-five) of the seventy-five patients stated that the knee with the revision felt better than the knee with the simultaneously performed primary arthroplasty. In the control group, the average knee score improved by 30 points on the side of the revision arthroplasty. However, forty-five of the sixty patients had a primary total knee arthroplasty on the contralateral side within two years after the index revision arthroplasty; by four years, all sixty patients had undergone a contralateral primary arthroplasty. CONCLUSIONS: We found a favorable outcome in patients who had undergone simultaneous revision and contralateral primary total knee arthroplasties. Despite a lower mean knee score and less motion, most patients seemed to prefer the knee with the revision arthroplasty to the knee with the primary procedure. These results suggest that this combined procedure is a safe and favorable alternative to a staged procedure consisting of revision and subsequent contralateral primary total knee arthroplasty.     

Once-weekly oral medication with alendronate does not prevent migration of knee prostheses: A double-blind randomized RSA study

Background and purpose Early migration of joint replacements is an effect of poor fixation and can predict late loosening. By reducing the bone resorption after implantation of a joint replacement, it should be possible to enhance the initial fixation of the implant. We studied the effect of once-weekly treatment with alendronate after knee replacement.Patients and methods We recruited 60 patients (60 knees) with gonarthrosis who were scheduled for a total knee replacement. They were operated on with identical implants and uncemented fixation. 30 patients were treated with a bisphosphonate (alendronate) and 30 patients underwent placebo treatment. The treatment started postoperatively and continued on a weekly basis for 6 months. The fixation of the implants was measured with repeated radiostereometry for 2 years.Results There was no difference in migration of implants between the two groups.Conclusion With uncemented fixation of knee implants, no benefit of once-weekly treatment with alendronate, starting postoperatively, could be seen during a 2-year follow-up period.     

Total condylar knee arthroplasty in osteoarthritis. A four- to six-year follow-up evaluation of 103 cases

One hundred and three consecutive total condylar knee prostheses in patients with gonarthrosis inserted from 1979 to 1981 have been prospectively followed for four to six years. According to the New York Hospital for Special Surgery Knee Rating Scale, 58 knees (56%) were rated excellent; 34 (33%), good; seven (7%), fair; and four (4%), poor at the latest follow-up evaluation. The median preoperative score was 57 points and the median postoperative score 87 points. Thirteen knees (13%) had a radiolucency with a width of 2 mm or more beneath one or more of three tibial zones. In only one case did this represent a clinical loosening. Six knees (6%) had complications requiring reoperation. One deep infection was treated with an arthrodesis, one patellar button was revised after a traumatic patellar fracture, and three superficial skin necroses were surgically managed. Moreover, in one mechanically loosened tibial component, a revision has been planned. No complications were fatal. The modified total condylar I prosthesis is an excellent prosthetic design with a low failure rate in gonarthrosis.     

Diagnosis specific differences in knee joint geometry. A challenge for the correct axial implantation of long stems in total knee arthroplasty

BACKGROUND: Arthrotic deformities with changes in knee geometry can produce difficulties in implanting long stem knee prosthesis systems using intramedullary alignment. They can result in incorrect lower limb axis and prosthesis positioning. The aim of the presented study was to measure knee geometry in patients with varus and valgus gonarthrosis in order to define diagnosis related differences. METHODS: A total of 75 patients with indication for total knee arthroplasty were divided in two groups using the weight bearing lower limb axis: patients with varus gonarthrosis (n=43) and with valgus gonarthrosis (n=32). Angles and extensions, important for knee prosthesis implantation, were measured, digitalized and analyzed. The results were investigated for diagnosis specific differences. RESULTS: After regulation of the measured extension in mean femur/tibia lengths, significant diagnosis specific differences were found: femur condyles were widened towards pathologic weight bearing (P<0.044), and the mechanical tibia axis of the varus gonarthrosis group is transferred to the lateral side (P<0.046) and in projection over the lateral internal cortical substance. CONCLUSION: The significant differences in deformed arthrotic knees indicate that for an optimal postoperative result the use of standard implants is not always sufficient. Modular knee prosthesis systems can provide adequately for individual demands.