全膝关节置换术中髌骨置换对骨性关节炎患者早期疗效及膝前痛的影响

目的：探讨全膝关节置换术中是否进行髌骨置换对骨性关节炎患者的临床疗效及术后疼痛的影响。方法笔者采用随机数字表法将骨科2011年5月～2013年7月收治的93例行人工全膝关节置换术患者分为髌骨置换组43例和未置换组50例,比较两组患者治疗前与治疗后不同时间的相关指标变化差异。结果术前髌骨置换组与非置换组的膝关节KSS（美国膝关节协会）评分、Feller评分差异不显著（ P＞0．05）;术后第3、6、12个月髌骨置换组膝关节KSS评分、Feller评分显著高于非置换组（P＜0．05）;术前髌骨置换组与非置换组的膝关节视觉模拟评分（VAS）差异不显著（P＞0．05）;术后第3、6、12个月髌骨置换组膝关节VAS评分显著低于非置换组（P＜0．05）;两组患者术前、术后的胫股角,髌韧带比值,关节活动度ROM屈、伸值在两组间比较差异均不显著（ P＞0．05）;术后第12个月两组患者的胫股角、髌韧带比值,关节活动度ROM屈、伸值较治疗前均显著好转（ P＜0．05）。结论全膝关节置换术中进行髌骨置换对改善膝关节功能评分、髌骨评分、术后疼痛评分均有显著的效果。     

Imaging patellar complications after knee arthroplasty

The purpose of this study is to describe complications affecting the patella in patients with total or partial knee arthroplasty. We respectively analysed plain-film radiographs, as well as ultrasound images when acquired, in a consecutive series of 1272 patients. The mean interval from knee replacement to patellar complications was 5 years and 7 months (range, 5 months to 14 years). The complications described include fracture, instability, dislocation or luxation, necrosis of the patella, infection of the patella, erosion of the patella, patellar impingement on the prosthesis and patellar or quadricipital tendon tear. We discuss the pathological imaging findings in the patella and their differential diagnosis after knee arthroplasty. Patellar complications after knee arthroplasty are uncommon but often potentially serious.     

Changes to patellar blood flow after minimally invasive total knee arthroplasty

Standard surgical exposure reduces blood flow to the patella during total knee arthroplasty (TKA). Reduction of patellar blood flow has resulted in patellofemoral complications including osteonecrosis and patellar fracture, necessitating revision surgery. In TKA, avoiding patellar eversion is one type of minimally invasive surgery (MIS) technique. This study is the first to measure patellar blood flow during MIS TKA with the knee in both extension and 90° of flexion followed by lateral retraction and then eversion of the patella. Patellar blood flow was measured using laser Doppler flowmetry in 40 patients during MIS TKA. A significant reduction in flow was noted when the leg was flexed from full extension to 90°. Eversion of the patella reduced patellar blood flow. MIS TKA without patellar eversion may be useful for preventing a reduction in patellar blood flow.     

Patellar fractures associated with medial-third bone-patellar tendon-bone autograft ACL reconstruction

Patella fractures following anterior cruciate ligament (ACL) reconstruction are a recognized but rarely reported complication. To our knowledge, 24 reports of patella fractures after ACL reconstruction using the central-third patella-tendon autograft have been reported in the literature. Patellar fractures associated with the use of the medial-third bone-patellar tendon-bone autograft have not been reported. This article describes four cases of patellar fractures in 478 ACL reconstructions between 1992 and 1999, using the medial third of the patellar tendon graft. All of them were transverse fractures of the patella but only one was displaced. All patients suffered local injury to the donor knee between 2 and 4 months postoperatively. No significant differences in the final outcome were noticed between the cases complicated with patellar fracture and those with uncomplicated ACL reconstructions.     

Effect of patellar thickness on early results of total knee replacement with patellar resurfacing

Purpose

Patellar thickness is a concern in total knee replacement with patellar resurfacing because of the risk of patellar fracture or implant loosening. The aim of this study was to evaluate if patellar thickness is related to clinical outcome in the absence of patellar fracture or implant loosening.

Methods

Early results of 169 patients who underwent total knee replacement with patellar resurfacing were reviewed to assess the effect of patellar thickness on clinical outcome. The mean follow-up was 13 months. The range of motion, Knee Society Score, Function Score and WOMAC Score were assessed preoperatively, at day 0, 6 months and 1 year. Radiographs were assessed for patellar fracture or implant loosening.

Results

Thirty-one percent of all patients had preoperative thickness <21 mm. Seven percent had <12 mm residual thickness after patellar cut, all were female. Twenty-three percent had ≥1 mm increase of thickness after surgery. Radiographs did not show any patellar fracture or implant loosening. However, preoperative patellar thickness <21 mm had poorer gain in range of motion at 1 year. Preoperative range of motion had greater influence on postoperative range of motion than preoperative patellar thickness. Residual thickness <12 mm had lower gain in WOMAC score at 1 year and an increase in thickness ≥1 mm postoperatively was associated with lower gain in WOMAC score at 6 months.

Conclusions

Early results of patellar resurfacing with preoperative thickness <21 mm or residual thickness <12 mm were found to be inferior even in the absence of patellar fracture or implant loosening. Conservative cutting resulting in 1 mm increase in thickness was also found to have inferior clinical results.

Level of evidence

II.     

Medial patellofemoral ligament avulsion injury at the patella: classification and clinical outcome

Purpose

To define medial patellofemoral ligament (MPFL) injury characteristics at the patellar attachment and clinical outcome in patients with primary traumatic patellar dislocation and MPFL avulsion injury at the patella.

Methods

Magnetic resonance imaging (MRI) was used to assess patients with primary (first-time) patellar dislocation and MPFL injury at the medial margin of the patella. Fifty-six patients with patellar attachment MPFL injury were enrolled in the study. Thirteen patients underwent surgical fixation of the avulsed MPFL and patellar medial margin osteochondral fracture, and the remaining patellar MPFL injures were treated nonoperatively. Forty-four patients were evaluated clinically at median four (range 1–10) years after patellar dislocation. The follow-up included evaluation of recurrent patellar instability, subjective symptoms, and functional limitations.

Results

Three types of patellar MPFL injuries were found; type P₀ with ligamentous disruption at the patellar attachment, type P₁ with bony avulsion fracture from the medial margin of the patella, and type P₂ with bony avulsion involving articular cartilage from the medial facet of the patella. Of the patellar MPFL avulsion injuries that underwent initial surgical fixation, two patients (2/13) reported an unstable patella at follow-up. Fifty-five per cent (17/31) of patellar MPFL avulsion injuries that were treated nonoperatively had recurrent patellar instability (n.s.). The median Kujala score was 90 for patellar avulsion with surgical fixation and 86 for patellar avulsion without surgical fixation (n.s.).

Conclusion

Patellar attachment MPFL injury showed three different patterns, classified as types P₀, P₁, and P₂. MRI can be used to assess the injury pattern. Patellar MPFL avulsion injuries do not benefit from acute surgical repair compared with nonsurgical treatment. Type P₂ patellar MPFL avulsion includes an osteochondral fracture that may require surgical fixation.

Level of evidence

Prognostic study, Level III.     

五角网缝合术治疗髌骨骨折的临床研究

目的 探讨一种操作简单、疗效可靠的治疗髌骨骨折手术方式.方法 髌骨骨折108例,男76例,女32例;年龄18～82岁,平均43岁.右侧骨折67例,左侧4l例.横断型骨折43例,粉碎型骨折54例,撕脱型骨折8例,纵型骨折3例.伤后至手术时间3 h～10 d.术中显露髌骨,复位,巾钳临时固定,用双股可吸收缝线编织一个五角星,呈网状置于髌骨前.用缝线穿过五角星的5个角,做双半环髌骨周围缝合,固定髌骨.这种称为"五角网缝合术"方法属张力带固定.实验采用20具新鲜牛膝关节,髌骨横断骨折,完全随机分成A、B两组,分别用五角网缝合术和AO张力带缝合术固定,在MTS试验机上对股四头肌进行加载测试,得出不同负荷(0～500 N)下骨折端分离距离.结果 108例髌骨骨折术后随访6～60个月,平均20个月,骨折均愈合.按Bost-man髌骨骨折疗效评价标准,优76例,良32例.力学试验表明,采用五角网缝合术和AO张力带缝合术的髌骨骨折端分离距离差异无统计学意义(P>0.05) 结论五角网缝合术治疗髌骨骨折,具有操作简单、固定牢固、术后可早期活动、康复快、疗效确切、无须二次手术取内固定等优点.     

Patellar polyethylene peg fracture: a case report and review of the literature

The patellar component of a total knee replacement (TKR) is the most frequent source of non-septic complications after total knee arthroplasty. Fracture of patellar pegs in all polyethylene patellar components is a very rare occurrence. We report such a case of a patellar polyethylene fracture in a 72-year-old female patient 10 years after TKR. Due to patellar malalignment and high level of activity, the patellar components failed in this patient. This was treated arthroscopically by removing the components that failed and leaving the patella unresurfaced. We followed up the patient postoperatively and her symptoms were substantially resolved.     

分叉克氏针治疗髌骨骨折

目的研究分叉克氏针治疗髌骨骨折的临床效果。方法用分叉克氏针治疗髌骨骨折27例,用经典的克氏针钢丝张力带固定治疗髌骨骨折32例。比较术后两组手术所用时间、骨折愈合时间、术后并发症、术后3个月时膝关节屈曲角度。结果分叉克氏针组临床骨折愈合时间平均(10±1.8)周,术后3个月关节屈曲角度平均为(120.5±11)°,手术时间平均65 m in。并发症发生率3.7%;经典克氏针钢丝张力带组临床骨折愈合时间平均(12±1.8)周,术后3个月膝关节屈曲角度平均(110.0±15.5)°,手术时间平均61 m in,并发症发生率28.1%。结论分叉克氏针治疗髌骨骨折相比克氏针钢丝张力带治疗,并发症发生率低,骨折愈合时间相对较短,关节功能恢复好,是一种有效的治疗方法。     

镍钛记忆合金聚髌器内固定治疗髌骨骨折的临床研究

目的：探讨镍钛记忆合金髌骨爪治疗髌骨骨折的临床应用与术后功能锻炼。方法：线性骨折采用复位钳复位髌骨,镍钛记忆合金髌骨爪髌骨内固定,粉碎性骨折先行可吸收缝合线环形荷包缝合固定髌骨后行髌骨爪髌骨内固定。结果：135例术后视骨折程度术后是否给予石膏托外固定,术后第2 d练习股四头肌锻炼,术后1周进行膝关节伸屈活动,术后2周扶拐下地行走。结论：镍钛记忆合金髌骨爪治疗髌骨骨折,周围组织刺激少、手术操作简单、骨折复位好、骨折愈合快、可早期恢复关节功能、避免髌骨切除,值得推广。     

Long-term osseous sequelae after acute trauma of the knee joint evaluated by MRI

OBJECTIVE: To evaluate the frequency and location and to determine the long-term MR changes in patients with edema-like bone marrow abnormalities after acute knee trauma. DESIGN AND PATIENTS: A cohort of 176 consecutive patients in a 29 month period with acute injury of the knee joint was examined with MRI. Forty-nine patients with bone marrow edema-like signal alteration on the initial MR examination were re-evaluated with MRI after a minimum of 2 years (mean 44 months). Signal alterations and contour abnormalities on the initial and follow-up MR examinations were classified. The volume of the edema was also measured. RESULTS: There was a prevalence of post-traumatic edema-like signal changes of 72% in 176 patients. In the follow-up group (n=49) the initial MR examination showed 80 areas of signal change with a mean volume of 15.5 cm3 (range 0.25-175 cm3). Thirty-five (44%) were signal changes without other bony or cartilaginous injuries, 19 (24%) were subchondral impaction fractures and 26 (33%) were osteochondral or chondral fractures. Sixty-nine percent of the lesions were located in the lateral, and 29% in the medial joint compartment. Three percent were patellar lesions. In seven of the 49 patients (14%) eight signal changes were seen on the follow-up MR examination. Six lesions were located in the same anatomic area as on the initial MR examination, and two new lesions had developed. The volume of the bone marrow edema was smaller in all persisting lesions (mean volume 2.26 cm3, range 0.3-4.8 cm3). Deterioration of the subchondral impaction, chondral/osteochondral fracture or lesions resembling osteonecrosis were not found in any patient. CONCLUSIONS: The majority of acute post-traumatic marrow signal changes are found in the lateral compartment and do not show additional osseous or chondral alterations. After a minimum of 2 years acute post-traumatic bone marrow edema-like signal alterations vanish in the majority of patients. Even more severe articular surface injuries such as subchondral bone impaction or chondral/osteochondral fractures will heal without obvious osseous long-term sequelae. Post-traumatic osteonecrosis, as reported in the literature, must be a rare event after acute knee trauma.     

Painful stress fractures of the fabella in patients with total knee arthroplasty

OBJECTIVE: The purpose of this study was to document a distinct pattern of stress fractures in the fabella of patients with total knee replacement and to call attention to this unusual complication that causes knee pain in postoperative patients. CONCLUSION: Stress fractures involving the fabella can be a clinically important entity in the patient with persistent or new knee pain after total knee arthroplasty. Scrutiny of radiographs, when coupled with clinical information, allows correct diagnosis of this potentially debilitating injury in symptomatic postoperative patients.     

Effectiveness of patellar bracing for treatment of patellofemoral pain syndrome.

OBJECTIVE: To determine the effectiveness of patellar bracing for treatment of patellofemoral pain syndrome (PFPS). DESIGN: Prospective, randomized, single-blinded clinical trial. SETTING: Subjects recruited from the general population of the city of Calgary. SUBJECTS: A total of 136 subjects (79 females and 57 males with a total of 197 affected knees) diagnosed with PFPS. INTERVENTION: Subjects were randomly assigned to 1 of 4 treatment groups: (1) home exercise program, (2) patellar bracing, (3) home exercise program with patellar bracing, and (4) home exercise program with knee sleeve. OUTCOME MEASURES: The outcome measurements were knee function (KF) and 10-cm visual analogue scale (VAS) pain ratings for 3 different situations: knee pain during sport activity, knee pain 1 hour after sport activity, and knee pain after sitting with knees bent for 30 minutes. The outcome measurements were assessed at baseline and at 3, 6, and 12 weeks. The investigators were blinded to the treatment group of each subject. Calculations were made for 95% confidence intervals for the change in KF and VAS pain ratings from baseline measurement to 12 weeks. RESULTS: There was no difference in the 95% confidence intervals in the change of KF and VAS pain ratings among the 4 treatment groups over 12 weeks. CONCLUSIONS: Symptoms of PFPS improved over time in terms of pain and knee function regardless of the treatment group. Patellar bracing did not improve the symptoms of PFPS more quickly when added to a home program of leg strengthening. However, patellar bracing alone can improve the symptoms of PFPS.     

两种方法治疗髌骨骨折效果观察

目的比较改良张力带与丝线环形缝合法内固定治疗髌骨骨折的临床效果。方法 86例髌骨骨折患者随机分为观察组和对照组各43例,观察组采用改良张力带治疗,对照组采用丝线环形缝合法内固定治疗。术后3个月,采用改良膝关节活动度（ROM）评价标准,对两组进行膝关节主动活动度测定;术后6个月,对两组行关节功能远期评定。结果观察组住院时间和手术时间均短于对照组;观察组3个月后膝关节活动度总有效率为90.7%,高于对照组的72.1%;6个月后远期临床总有效率为95.3%,高于对照组的76.7%（P均〈0.05）。结论改良张力带治疗髌骨骨折操作简便,术后恢复快,治疗效果优于丝线环扎内固定法。     

Acute osteoporotic and neoplastic vertebral compression fractures: fluid sign at MR imaging

PURPOSE: To evaluate the occurrence, location, and shape of the fluid sign in acute osteoporotic and neoplastic vertebral compression fractures at magnetic resonance (MR) imaging. MATERIALS AND METHODS: The study group comprised 87 consecutive patients with acute vertebral compression fractures due to osteoporotic (n = 52) or neoplastic (n = 35) infiltration. The MR imaging protocol included nonenhanced T1-weighted spin-echo and short inversion time inversion-recovery sequences and a 1.5-T system. Readers blinded to the outcome documented the occurrence, shape, and location of the fluid sign with consensus. The fluid sign was correlated with the cause, age, and severity of the fracture. The diagnosis was confirmed with surgery, follow-up MR imaging, clinical follow-up, or unequivocal imaging findings. Wilcoxon and chi(2) tests were used to assess significance. RESULTS: In fractured vertebral bodies, the fluid sign was adjacent to the fractured end plates and exhibited signal intensity isointense to that of cerebrospinal fluid. The fluid sign was linear (n = 16), triangular (n = 5), or focal (n = 2) and was significantly associated with osteoporotic fractures (21 [40%] of 52; P <.001). The fluid sign occurred in two (6%) of 35 neoplastic compression fractures. Histologic examination demonstrated osteonecrosis, edema, and fibrosis at the site of the fluid sign. There was a tendency toward older fractures exhibiting the fluid sign, but this relationship was not significant (P >.05). In osteoporotic fractures, the fluid sign was significantly associated with fracture severity (P <.05). CONCLUSION: The fluid sign is featured in acute vertebral compression fractures that show bone marrow edema. It can be an additional sign of osteoporosis and rarely occurs in metastatic fractures.     

The effects of patellar taping on patellofemoral incongruence. A computed tomography study

Patellar taping for the purpose of patellar medialization is a nonoperative rehabilitation technique used in the treatment of patellofemoral pain. Despite early reports of excellent success rates, the indications for this treatment and its efficacy on patellofemoral pain are unclear. The present computed tomography study was undertaken to evaluate the effect of patellar taping on patellofemoral incongruence. Sixteen female patients (age range, 16 to 25 years) with anterior knee pain related to patellofemoral incongruence underwent computed tomography examination with their quadriceps muscles relaxed and contracted both before and after patellar taping. Patellar lateralization was measured as lateral patellar displacement, and patellar tilt was measured as lateral patellar angle. Patellar taping did not significantly affect patellofemoral lateralization or tilt. The results of this study do not support the use of this method for passive correction of patellofemoral incongruence. Although patellar taping may well be effective in controlling anterior knee pain during physical therapy, it does not do so by medializing the patella.     

Clinical and radiological outcome of medial patellofemoral ligament reconstruction with a semitendinosus autograft for patella instability

Background: Recurrent patellar instability is a common problem after dislocation. The medial patellofemoral ligament (MPFL) contributes 40–80% of the total medial restraining forces. This study assessed the clinical and radiological outcome after a follow-up of 4 years after linear MPFL reconstruction using an ipsilateral Semitendinosus tendon autograft. Study design and methods: 15 knees in 12 patients were examined with a mean of 47 months after linear reconstruction of the MPFL at a mean age of 30 years. 3 knees underwent previous surgery. 3 patients had mild trochlear dysplasia grade I or II, according to the classification of Dejour. If preoperative tibial tuberosity-trochlear groove distance (TTTG) was more than 15 mm, patients underwent additional medialisation of the tibial tuberosity (n=8) creating a similar postoperative situation for all patients. All patients were available for a postoperative evaluation, which consisted of a subjective questionnaire, the Kujala score, and the recording of potential patellar redislocation and apprehension. Patellar height and tilt was measured on plain radiographs. Postoperative CT scans were performed in patients with an additional tibial tuberosity-transfer. Results: Postoperatively, one patient reported on recurrent bilateral redislocation. Physical examination however revealed no findings. Three knees presented with persistent patellar apprehension. Thirteen knees had improved subjectively after surgery. The mean Kujala score improved significantly from 55.0 to 85.7 points. The patellar tilt decreased significantly from 11.3° to 9.2°. Four knees had patella alta preoperatively, but only two at the latest follow-up visit. Previous surgery or additional trochlear dysplasia had no influence on the clinical outcome. Conclusion: MPFL reconstruction improves clinical symptoms, reduces the patellar tilt substantially, and may correct patella alta. Additional mild trochlear dysplasia did not compromise the outcome; however, this fact needs further attention in a larger study group.     

Decreasing patellar tendon stiffness during exercise therapy for patellar tendinopathy is associated with better outcome

ObjectivesTo assess the associations between: 1) baseline patellar tendon stiffness and clinical outcome after exercise therapy in athletes with patellar tendinopathy and 2) the change in patellar tendon stiffness and clinical outcome during progressive tendon-loading exercise therapy and eccentric exercise therapy.DesignRandomized controlled trial.MethodsAthletes with patellar tendinopathy aged 18-35 years, playing tendon-loading sports at least 3 times per week were randomized in a 1:1 ratio between progressive tendon-loading exercise therapy and eccentric exercise therapy for 24 weeks. Patellar tendinopathy was diagnosed clinically, and confirmed by ultrasound. Patellar tendon stiffness (kilopascal, kPa) was assessed using shear-wave elastography. Clinical outcome was assessed using the validated Victorian Institute of Sports Assessment (VISA-P; range 0-100) questionnaire. Both were assessed at baseline, 12 and 24 week follow-up. Adjusted general linear, mixed-linear models and Generalized Estimating Equations were used.ResultsWe included 76 athletes (58 men, mean age 24 ± 4 years). No association was found between baseline stiffness and VISA-P after 24 weeks (p = 0.52). Decreased stiffness (adjusted mean difference = 10 kPa (95% CI: 4-15) was significantly associated with improved clinical outcome at 12 weeks in all athletes (p = 0.02), and at both 12 and 24 weeks (p = 0.01) in athletes allocated to progressive tendon-loading exercise therapy.ConclusionsPatellar tendon stiffness, assessed with shear-wave elastography, is unsuitable to use as a single predictive measurement for clinical outcome. Decreasing stiffness during the course of exercise therapy is associated with improved clinical outcome in athletes recovering from patellar tendinopathy.     

内固定和外固定应用于髌骨骨折固定中疗效及依从性比较

目的对临床常用的髌骨骨折内外固定方法的疗效及手术依从性进行分析,证实抓髌器外固定的临床优势。方法将我院2007年1月-2012年12月间手术治疗的128例髌骨骨折患者随机分为2组,每组研究对象64例。一组使用抓髌器外固定,为观察组;一组使用克氏针张力内固定,为对照组;治疗后对两组研究对象的骨折愈合、并发症、关节功能、患者满意率等临床数据进行比较及统计学分析。结果观察组62例、对照组58例骨折愈合良好,观察组愈合优良率（96．9％）高于对照组（90．6％）,且具有显著差异性（P〈0．05）;在感染发生率及关节功能的比较中,观察组均优于对照组,且具有显著差异性（P〈0．05）;观察组患者满意率为98．4％,均优于对照组,且具有显著差异性（P〈0．05）。结论抓髌器外固定在髌骨骨折治疗中的疗效及依从性较克氏针张力内固定具有显著优势,尤其在髌骨粉碎性骨折中优势更加明显,适于临床推广使用。     

外侧髌旁切口膝关节半伸直位关节外髓内钉技术治疗胫骨干骨折的临床疗效分析

目的探讨分析外侧髌旁切口膝关节半伸直位关节外髓内钉技术治疗胫骨干骨折的临床疗效。方法笔者回顾性分析2012年6月~2013年9月收治的胫骨干骨折患者24例,男性15例,女性9例;年龄17~63岁,平均40岁。其中胫骨上1/4骨折17例,胫骨干骨折合并髌骨前皮肤软组织挫伤7例;均符合髓内钉固定治疗。24例患者均采取经外侧髌腱旁入路,关节外髓内钉植入技术,并得到了12个月以上的随访。随访期间,采用视觉模拟评分法(VAS),客观的活动度评分和功能障碍评分来反映膝前痛程度、关节的活动度。结果 7例胫骨干骨折合并髌骨前皮肤软组织挫伤的患者由于采用了髌旁外侧切口,切口均良好愈合。所有24例患者在术后3~6周的随访期间,80.16%的患者有膝前疼痛;但术后3个月的随访显示79.6%的患者膝前疼痛均消失,膝关节的屈伸功能及活动度均较满意。根据VAS评分及活动度评分,优15例,良7例,差2例,总优良率为91.66%。各年龄阶段无明显差异。结论外侧髌旁切口膝关节半伸直位关节外髓内钉技术,尤其对于合并髌骨前皮肤软组织挫伤者,可以大大减少切口感染及皮肤坏死的概率,而且手术复位操作简便,影像学透视优势明显。术后膝关节膝前痛的发生率低,关节功能恢复良好,尤其适用于胫骨上1/4骨折及胫骨干骨折合并髌骨前皮肤软组织挫伤的患者。