Peroneal nerve palsy after total knee arthroplasty

Peroneal nerve palsy after TKA, although uncommon, can be a troublesome complication for patients and surgeons. The predisposing factors must be recognized and meticulous surgical techniques and vigilant postoperative care must be undertaken to minimize their effects. Although effective intervention still remains to be determined, most patients do proceed to complete recovery from the nerve palsy but demonstrate good functional capacity.To our knowledge, there are no prospective studies that clearly elucidate the effect of the previously mentioned risk factors on the incidence of peroneal nerve palsy after TKA. More research is needed to tease out these risk factors and explore treatment strategies. A prospective randomized controlled study may help determine the optimal treatment strategy for this important clinical problem.     

初次全膝关节置换术后腓总神经麻痹的原因及处理

目的探讨初次全膝关节置换术（TKA）术后腓总神经麻痹产生的原因及处理。方法对2002年1月至2009年12月本院有完整记录的1257例初次TKA患者中术后出现腓总神经麻痹的病例进行回顾分析并随访14～56个月,其中一期双侧TKA 4例,单侧TKA 2例;术前诊断骨关节炎3例,类风湿关节炎2例,血友病关节炎1例。结果 6例（0.47%）术后出现腓总神经麻痹,可能的原因包括术中拉钩位置不当,术后血肿压迫,神经阻滞麻醉过程针刺伤,止血带时间过长,术后加压包扎过紧,严重膝外翻屈曲畸形矫形。5例（83.3%）完全恢复,1例行神经探查手术,术后症状一度加重,随访术后6个月运动功能恢复,但目前仍残留感觉麻木。结论初次TKA术后腓总神经麻痹是多种因素造成的,预防是关键,围手术期应注意识别可能发生的一些危险因素并谨慎操作。保守治疗可获得满意效果,神经探查手术应慎重。     

膝关节置换术中腓总神经损伤的原因与预防

[目的]了解膝关节置换术（TKA）中腓总神经损伤的原因及预防要点。[方法]回顾总结本院1996年1月～2007年6月2000例初次TKA术后腓总神经麻痹患者的致伤原因。6例新鲜完整正常人体下肢标本模拟行TKA术，观察术中容易损伤腓总神经的操作步骤。[结果]9（0．45％）例患者术中腓总神经出现不明原因损伤。标本模拟手术过程证实，术中可能导致腓总神经损伤的高危操作依次为：①松解股骨后外侧关节囊、腓肠肌外侧头时，助手自后向前环抱提拉股骨远端将腓总神经压迫贴近股骨，后外侧骨面大大增加腓总神经挫伤几率，且术后多为其深、浅支同时出现症状。②外侧Hoffman板钩放置位置偏于外侧副韧带后侧或深度过大，钩尖部在运动中容易划伤腓总神经，术后多为深支或浅支的不全损伤。③安装假体试模后，为纠正残余屈曲角度，强力完全伸直或过仰，容易导致腓总神经牵拉伤。[结论]术中松解后外侧关节囊、腓肠肌外侧头时，应该避免助手自后向前环抱股骨远端向上提拉。注意Hoffman板钩位置、插入方向及其深度。避免强力过伸膝关节。     

Common peroneal nerve palsy after lateral unicompartmental knee arthroplasty

Unicompartmental knee arthroplasty is now being used more commonly to treat single compartment disease of knee, with very encouraging results. We report on a rare case of common peroneal nerve palsy; 8 years after lateral unicompartmental knee arthroplasty. This palsy was caused by pressure on the common peroneal nerve, due to posterior migration of tibial component.     

Delayed transient sciatic nerve palsy after total hip arthroplasty

Sciatic nerve palsy after total hip arthroplasty is a well-known complication, but delayed sciatic nerve palsy is rare. We report such a case with profound clinical manifestations and well-documented electrophysiologic changes. We found no helpful guidance to managing delayed palsy in the literature. We also are unaware of any previous cases reported in which nearly full recovery has occurred.     

Peroneal nerve palsy after ankle sprain: an update

Ankle sprains are extremely common in the general population and the most common injuries in athletes. Although rare, peroneal nerve palsy may occur simultaneously with ankle sprain. The exact incidence of nerve injury after ankle sprain is not known; few cases of peroneal nerve palsy associated with ankle sprains have been reported in the literature. The function of the peroneal nerve should be evaluated in all patients with a history of inversion ankle sprain as part of the initial and follow-up evaluation, even if the initial neurological status is normal, because delayed peroneal nerve palsy is possible. This article discusses the incidence, pathophysiology, evaluation, diagnosis and differential diagnosis, and management of the patients with peroneal nerve palsy after ankle sprain aiming to increase the awareness of the treating physicians for this nerve injury.     

Complications after total knee arthroplasty

Complications after total knee arthroplasty were evaluated prospectively after a total of 321 procedures. 53 (16.5 %) patients showed postoperative courses deviating from the routine. Of these 5.0 % developed clinically relevant deep vein thromboses, the rate of deep infections was 1.6 %, 3.7 % of the patients suffered from persisting or recurrent joint effusions, arthrofibrosis was observed in 4.4 % of the patients and 1.9 % were affected by wound complications. In most patients deep infections were treated by removal of the implants and reimplantation after clearing of the infection. The primary treatment of arthrofibrosis consisted of manipulation under general or regional anaesthesia. Patients with recurrent joint effusions received punctions, which had to be repeated in some cases. In one patient an intraarticular drainage had to be inserted. The conservative or surgical therapy of wound complications depended on the patient's situation. In patients with thrombosis distal to the trifurcation of the popliteal vein anticoagulation with heparin was continued. In contrast, in patients with femoral or popliteal venous thrombosis the anticoagulation was changed to cumarine derivates.     

Arthrofibrosis after total knee arthroplasty

Six total knee arthroplasties in five patients were revised because of persistent limited motion after the primary arthroplasty. All of the revised implants were of an appropriate size and not malpositioned. No cause of stiffness was identified other than soft tissue contracture. Four of the components were posterior cruciate retaining and two were posterior cruciate substituting. Heterotopic bone formation was observed in two knees before the revision surgery and five knees after the revision surgery. Arc of motion was increased from 36 degrees (range, 20 degrees-70 degrees) before revision surgery to 86 degrees (range, 70 degrees-110 degrees) after revision surgery. What triggers the proliferation of extensive scar tissue formation in patients with arthrofibrosis is not clear. Some patients may be predisposed to this condition or may have it develop as a response to the surgical trauma and postoperative rehabilitation. However, when arthrofibrosis does develop after total knee arthroplasty, some improvement in motion and pain can be achieved with revision surgery.     

膝关节置换术后冷疗的研究现状

目前在全膝关节置换术后常常使用冷冻治疗来促进其恢复,其在理论上具有减少出血、缓解疼痛等作用,但是关于冷冻治疗的使用及有效性仍然存在一定的争议,本文就目前临床上关于冷冻治疗的生理基础、不同作用的有效性、不同冷疗方法的选择及并发症等方面的研究加以综述。     

Manipulation after total knee arthroplasty

BACKGROUND: Following total knee arthroplasty, some patients who fail to achieve >90 degrees of flexion in the early perioperative period may be considered candidates for manipulation of the knee under anesthesia. The purpose of this study was to assess the outcomes of manipulation following total knee arthroplasty. METHODS: One hundred and thirteen knees in ninety patients underwent manipulation for postoperative flexion of < or =90 degrees at a mean of ten weeks after surgery. Flexion was measured with a goniometer prior to total knee arthroplasty, at the conclusion of the operative procedure, before manipulation, immediately after manipulation, at six months, and at one, three, and five years postoperatively. RESULTS: Eighty-one (90%) of the ninety patients achieved improvement of ultimate knee flexion following manipulation. The average flexion was 102 degrees prior to total knee arthroplasty, 111 degrees following skin closure, and 70 degrees before manipulation. The average improvement in flexion from the measurement made before manipulation to that recorded at the five-year follow-up was 35 degrees (p < 0.0001, paired t test). There was no significant difference in the mean improvement in flexion when patients who had manipulation within twelve weeks postoperatively were compared with those who had manipulation more than twelve weeks postoperatively. Patients who eventually underwent manipulation had significantly lower preoperative Knee Society pain scores (more pain) than those who had not had manipulation (p = 0.0027). CONCLUSIONS: Manipulation generally increases ultimate flexion following total knee arthroplasty. Patients with severe preoperative pain are more likely to require manipulation.     

Stiffness after total knee arthroplasty

Postoperative stiffness is a debilitating complication of total knee arthroplasty. Preoperative risk factors include limited range of motion, underlying diagnosis, and history of prior surgery. Intraoperative factors include improper flexion-extension gap balancing, oversizing or malpositioning of components, inadequate femoral or tibial resection, excessive joint line elevation, creation of an anterior tibial slope, and inadequate resection of posterior osteophytes. Postoperative factors include poor patient motivation, arthrofibrosis, infection, complex regional pain syndrome, and heterotopic ossification. The first steps in treating stiffness are mobilizing the patient and instituting physical therapy. If these interventions fail, options include manipulation, lysis of adhesions, and revision arthroplasty. Closed manipulation is most successful within the first 3 months after total knee arthroplasty. Arthroscopic or modified open lysis of adhesions can be considered after 3 months. Revision arthroplasty is preferred for stiffness from malpositioned or oversized components. Patients who initially achieve adequate range of motion (>90 degrees of flexion) but subsequently develop stiffness more than 3 months after surgery should be assessed for intrinsic as well as extrinsic causes.     

Infection after total knee arthroplasty

The aim of our study was to determine the current incidence and outcome of infected total knee arthroplasty (TKA) in our unit comparing them with our earlier audit in 1986, which had revealed infection rates of 4.4% after 471 primary TKAs and 15% after 23 revision TKAs at a mean follow-up of 2.8 years. In the interim we introduced stringent antibiotic prophylaxis, and the routine use of occlusive clothing within vertical laminar flow theatres and 0.05% chlorhexidine lavage during arthroplasty surgery. We followed up 931 primary TKAs and 69 revision TKAs for a mean of 6.5 years (5 to 8). Patients were traced by postal questionnaire, telephone interview or examination of case notes of the deceased. Nine (1%) of the patients who underwent primary TKA, and four (5.8%) of those who underwent revision TKA developed deep infection. Two of nine patients (22.2%) who developed infection after primary TKA were successfully treated without further surgery. All four of the patients who had infection after revision TKA had a poor outcome with one amputation, one chronic discharging sinus and two arthrodeses. Patients who underwent an arthrodesis had comparable Oxford knee scores to those who underwent a two-stage revision. Although infection rates have declined with the introduction of prophylactic measures, and more patients are undergoing TKA, the outcome of infected TKA has improved very little.     

Osteolysis after total knee arthroplasty

Osteolysis ranks as the most significant cause of revision surgery in both total hip arthroplasty and total knee arthroplasty (TKA). The factors leading to osteolysis in TKA are unique and sometimes preventable. Changes in polyethylene manufacturing and implant design are striving to improve overall wear. In this review, we discuss osteolysis as it relates to TKAs. The etiology, diagnosis, contributing factors, and management are presented. The final section focuses on future improvements in TKA design, which may ultimately decrease the rate of osteolysis.     

Pseudogout after total knee arthroplasty

We report a case of a patient who presented with signs and symptoms of acute septic arthritis of the knee 9 years after total knee arthroplasty. Thick white purulent fluid was aspirated from the knee. Microscopy of the fluid demonstrated calcium pyrophosphate dihydrate crystals, and no organisms were cultured. The patient made a rapid recovery after the single aspiration, rest, and nonsteroidal antiinflammatory drugs alone. Eight years after this episode, the patient remains asymptomatic. To the best of our knowledge, no case of calcium pyrophosphate dihydrate arthropathy after total knee arthroplasty has been reported previously.     

Late sciatic nerve palsy caused by hematoma after primary total hip arthroplasty

A case of late sciatic nerve palsy caused by subfascial hematoma after uncemented right total hip arthroplasty is reported. The patient developed respiratory distress 13 days postoperatively and was admitted to another institution, where she was diagnosed with pulmonary embolism and was subsequently therapeutically anticoagulated with heparin. The patient complained of right-leg numbness and tingling 18 days' postoperatively, which progressed to complete sciatic nerve palsy over several hours.