Use of a turndown quadriceps tendon flap for rupture of the patellar tendon after total knee arthroplasty

Patellar tendon rupture is a devastating complication after total knee arthroplasty. The results of surgical treatment of this complication were discouraging in most of the reports. We describe a case of rupture of patellar tendon 7 weeks after total knee arthroplasty treated with a turndown quadriceps flap and circumferential wiring. Two years and 6 months after operation, the patient had no extension lag of the knee and knee flexion to 110 degrees .     

Radiolucent zone of the patella following total knee arthroplasty without patellar resurfacing

Background

The radiolucent zones in the patella are sometimes observed in patients who have undergone total knee arthroplasty (TKA) without patellar resurfacing. On the basis of radiological findings from our clinical experience, we hypothesize that the pathogenesis of this lesion may be similar to that of the lesions of spontaneous osteonecrosis, and this lesion may be due to both osteoporosis and stress concentration. The present study aimed to determine the incidence of the radiolucent zone after TKA without patellar resurfacing. Moreover, the roles of osteoporosis and patellar morphology, which are related to the stress distribution in the patella, were also investigated.

Methods

We studied 48 knees of 38 patients who underwent primary TKA using the Genesis II prosthesis. Axial radiographs taken 1 year postoperatively were used to assess the incidence of the radiolucent zone. The World Health Organization fracture risk assessment tool (FRAX) score and the preoperative patellar facet angle were compared between patients with and without the radiolucent zones.

Results

Five patellae (10.4 %) showed the radiolucent zones postoperatively (the radiolucent group), whereas no such lesions were found in the remaining 43 patellae (the normal group). The major osteoporotic fracture risk of the radiolucent group calculated using the FRAX was 24.8 % and significantly higher than that in the normal group (14.7 %; p = 0.01). The average patellar facet angle in the radiolucent group was 123.6°, which was significantly smaller than that in the normal group (133.6°; p = 0.003).

Discussion and conclusions

The results of the present study suggest that both underlying osteoporosis and a steep patellar facet angle may play an important role in the pathogenesis of the radiolucent zones in patellae after TKA without patellar resurfacing. Patellar resurfacing may be considered, particularly in osteoporotic patients who have a steep patellar facet angle, to avoid the appearance of the postoperative radiolucent zone in the patella.     

Radiographic changes in the patella following quadriceps turndown for revision total knee arthroplasty

Quadriceps turndown is a technique that may be used to enhance exposure of the tight total knee arthroplasty (TKA), particularly in the revision scenario. This technique does, however, compromise the vascularity of the patella, with avascular necrosis (AVN) being a possible sequela. A modified Coonse-Adams quadriceps turndown was performed in 29 revision TKAs in 27 patients. Immediate preoperative and sequential postoperative radiographs were analyzed for changes in the patella, including sclerosis, flattening, fracture, and fragmentation, as evidence of possible AVN, and clinical scores were collected prospectively. Eight patellae had such radiographic changes. Despite a lack of corresponding worsening in clinical outcome in these patients, quadriceps turndown is shown to have a high risk of subsequent changes consistent with patellar AVN, and should be avoided when other available techniques can achieve satisfactory exposure.     

Patellotibial fusion for patellar tendon rupture after total knee arthroplasty

Patellar tendon rupture is a rare but recognized complication of total knee arthroplasty. Multiple repair methods have been described in the literature. This unique case involved a patient with an underlying metabolic disorder and poor soft tissue quality. A patellotibial fusion was used to achieve a more definitive reestablishment of the extensor mechanism and to improve the patient's level of activity.     

Suture anchor repair of quadriceps tendon rupture after total knee arthroplasty

Disruption of the extensor mechanism after total knee arthroplasty (TKA) is a devastating complication, usually requiring surgical repair. Although suture anchor fixation is well described for repair of the ruptured native knee quadriceps tendon, no study has discussed the use of suture anchors in quadriceps repair after TKA. We present an illustrative case of successful suture anchor fixation of the quadriceps mechanism after TKA. The procedure has been performed in a total of 3 patients. A surgical technique and brief review of the literature follows. Suture anchor fixation of the quadriceps tendon is a viable option in the setting of rupture after TKA.     

Endosteal referencing in revision total knee arthroplasty

A method of orienting the femoral and tibial bone cuts relative to the endosteal cortex of the femur and tibia was used in 32 patients who underwent revision total knee arthroplasty. The mean orientation of the femoral component was 96.74° ± 1.03°, mean orientation of the tibial baseplate was 90.71° ± 1.10°, mean anatomic tibiofemoral alignment was 7.42° ± 1.69° of valgus, and mean mechanical tibiofemoral alignment was 1.09° ± 1.83° of valgus. Mean tibial bowing was 1.63° ± 1.57° of valgus, and mean femoral bowing was 0.58° ± 1.53° of varus. Valgus tibial bowing was correlated with valgus orientation of the tibial component (r = .86, P < .000001), and varus femoral bowing was correlated with orientation of the femoral component (r = .54, P = .0054). Referencing the implant position from the endosteal cortex of the intramedullary canals provides a reliable method of achieving satisfactory alignment in most revision total knee arthroplasties; however, bowing of the femur or tibia can affect alignment.     

Should the patella be resurfaced in total knee arthroplasty? Efficacy of patellar resurfacing

To assess the long-term efficacy of patellar resurfacing, 100 knees were evaluated in 84 patients. The operations were performed between 1978 and 1982. The follow-up period ranged from 60 to 103 months. The diagnosis was degenerative joint disease (DJD) in 83%, rheumatoid arthritis in 12%, and miscellaneous in 5% of the knees. The implant (47 knees) and nonimplant (53 knees) groups were comparable with respect to age, body size, and length of follow-up period. The analysis revealed equivocal results. Considering all diagnostic categories combined, rest pain was marginally better in the resurfaced group (p = 0.04), but this difference resulted from an unequal distribution of subjects between mild and zero pain categories. Pain with walking, maximum walking distance, ability to climb stairs and rise from a chair, active arc of motion, extensor lag, and quadriceps strength were similar in the two groups. When the DJD group was considered separately, no significant difference emerged. There was little evidence to support a recommendation for routine patellar resurfacing in total knee arthroplasty.     

Advanced osteoarthritic knee with neglected patellar tendon rupture treated with total patellectomy and total knee arthroplasty

Loss of the knee extensor mechanism results in a change of normal knee joint alignment and functional anteroposterior instability. In patients with neglected or chronic patellar tendon rupture, advanced degenerative change of the knee joints may develop at the later stage. We present a case of a 64-year-old man with chronic left patellar tendon rupture and 10-cm proximal patella migration associated with advanced osteoarthritis of the knee. Total patellectomy and simultaneous total knee arthroplasty (TKA) relieved his symptoms and disability successfully. His left knee still did well at 7-year follow-up.     

Reconstruction of a ruptured patellar tendon with achilles tendon allograft following total knee arthroplasty

BACKGROUND: Rupture of the patellar tendon after total knee arthroplasty is a rare and debilitating complication. Proper surgical management of this condition remains controversial. The purpose of this study was to review the results of reconstruction of a ruptured patellar tendon with an Achilles tendon allograft following total knee arthroplasty. METHODS: We reviewed our experience with the use of a fresh-frozen Achilles tendon allograft with an attached calcaneal bone graft to restore extensor function in nine patients with patellar tendon rupture following total knee arthroplasty (five primary and four revision). All patients were examined clinically and radiographically at an average of twenty-eight months. RESULTS: The average knee and functional scores improved from 26 and 14 points, respectively, before the surgery to 81 and 53 points after the surgery. The average extensor lag decreased from 44 degrees preoperatively to 3 degrees postoperatively, and the average range of motion of the knee increased from 88 degrees to 107 degrees. Two grafts failed in the early postoperative period. Both were repaired successfully. Radiographs showed an average proximal patellar migration of 17.8 mm, which did not appear to affect extensor function. CONCLUSIONS: This short-term follow-up study showed that once an Achilles allograft has healed, it can serve as a reliable reconstruction of a ruptured patellar tendon following total knee arthroplasty. This technique may be particularly suited for patients in whom the extensor mechanism was compromised by multiple prior operations. Continued follow-up is necessary to determine the long-term durability of these results.     

Rupture of the quadriceps tendon after total knee arthroplasty: A case report

Reported herein is the case of a 45-year-old woman with knee involvement due to rheumatoid arthritis. She had a total knee arthroplasty with a rupture of the quadriceps tendon 1 month later. Surgical repair of the rupture was performed following the Scuderi technique plus reinforcement with Dacron (Lig Aid, Levallois, Cedex. France) tape cerclage. An above-knee walking-plaster cast was applied with the knee in full extension for 6 weeks. The functional result was good 1 year after surgery.     

Intraoperative patellar tendon strain: predicting the range of knee flexion after total knee arthroplasty

Background  The preoperative range of motion is an important factor that influences the range of motion after total knee arthroplasty. Because the length and tightness of the extensor mechanism are extracapsular elements with an influence on knee flexion, it is reasonable to assume that the tension of the knee extensor mechanism during surgery has a considerable impact on the postoperative range of motion. The purpose of this study was to determine the influence of the tightness of knee extensor mechanism on postoperative knee flexion. Methods  In 18 knees undergoing posterior-stabilized type total knee arthroplasty, we measured the longitudinal strain on the patellar tendon with all the components in position during passive knee flexion up to 135°. The patellar tendon strains measured during surgery were compared with the preoperative maximum knee flexion angle and postoperative maximum knee flexion angle at 1 year. Results  There was a significant inverse correlation between the patellar tendon strain during surgery at 60° (r = -0.54, P < 0.05), 90° (r = -0.55, P < 0.05), or 135° of flexion (r = -0.65, P < 0.05) and postoperative knee flexion. Conclusions  The results indicated that subjects with high intraoperative patellar tendon strain during passive flexion of the knee had more restricted postoperative knee flexion. Therefore, the tightness of the knee extensor mechanism measured at total knee arthroplasty is a good predictor of maximum postoperative range of flexion.     

A new concept for precise patella resection in total knee arthroplasty.

We developed a new patella-cutting guide that simplifies proper alignment and enables resection of the correct thickness of bone. This guide consists of a central shaft, two support frames, and a ring. The ring consists of upper and lower disks, with a slot between the disks. The central shaft and the lower disk have holes for fixation pins. The distance from the distal end of the central shaft to the lowest level of the slot is 8 mm. Bone of the same thickness as that of the patellar component can be automatically resected using this guide. A feeler gauge is inserted through the slot, and the periarticular region is felt. This procedure enables the guide to be set at the correct angulation. A laboratory study using fresh-frozen cadaver patella specimens and a clinical study showed that proper alignment and proper resection were achieved using this guide.     

全膝关节置换术中髌骨处理

全膝关节置换术中是否进行髌骨置换仍有争论,术后膝前疼痛及髌股关节并发症是争论的焦点.膝前疼痛是多种因素共同作用的结果,不能简单地归咎为髌骨置换与否.全膝关节置换时是否置换髌骨应考虑原发病、病变程度、假体类型及患者活动量和体重等诸多因素.如果行髌骨置换,精湛的外科技术、合适的假体是全膝关节置换术后髌股关节并发症减少的关键;如果不行髌骨置换,患者的筛选标准是保证手术疗效的关键.     

Medialization of the patella in total knee arthroplasty

Patellar complications of total knee arthroplasty remain the most common cause of pain and reoperation. Laboratory studies have suggested that medialization of the patella will improve tracking of the patella on the trochlea of the femoral component. The purpose of this study was to determine if clinical medialization of the patellar component on the patellar bone would improve tracking of the patella as demonstrated radiographically. Sixty-two knees were randomized so that 31 knees had a centrally placed patellar component and 31 had the patellar component placed on the medial two thirds of the patellar bone. There was no difference between the two groups with respect to either clinical or radiographic results in the first year after surgery. There was no improvement compared with previous reports in the incidence of tilt and displacement. The one improvement was a reduction in the incidence of lateral release. Thus, consequences of lateral release such as postoperative morbidity, avascular necrosis of the patella, and stress fracture of the patella can be avoided. It is recommended that the patellar component be placed on the medial two thirds of the patella to reduce the occurrence of lateral release. Tracking of the patella during surgery can be assessed using a single suture placed at the superior pole of the patella, and this technique in combination with the no-thumbs test provides an additional means of evaluation for patellar tracking.     

Asymmetric patella resurfacing in total knee arthroplasty

Three hundred consecutive primary, cemented, condylar total knee arthroplasties (TKAs) were reviewed for the presence of asymmetric patella resurfacing using a postoperative Merchant or sunrise patellar radiograph. Twenty-one knees in 14 patients were found to have the patella asymmetrically resurfaced. Asymmetric resurfacing typically involved the inadvertent preferential resurfacing of the lateral facet with underresection of bone from the medial patellar facet. All patients underwent follow-up for a minimum of 5 years, with a mean follow-up of 7.5 years. Of the 21 knees, 3 revisions were required for patellar complications. One patellar component was loose on radiographs and there was marked patellofemoral pain in 6 knees. Overall, 11 of 21 knees (52%) underwent revision or were recommended for revision for patellar complications or had anterior knee pain that limited activities. Inadvertent asymmetric patella resurfacing using the kinematic condylar implant adversely affects the outcome after TKA.     

The patella in total knee arthroplasty.

Controversy persists as to whether the patella should be resurfaced in total knee arthroplasty. Can the good results of patellar cartilage against the metal femoral component be expected to endure? Attention to technique can be expected to reduce some of the complications of resurfacing, notably fracture, rupture, and instability. Component breakage results from metal-backed designs, and the causes of patellar clunks have not been fully understood.     

全膝关节置换术髌骨相关问题的探讨

髌骨是人体最大的籽骨，它是伸膝装置的重要组成部分，在20世纪的早、中期，髌骨的重要性并不为人们所重视。自1971年Kaufer报告髌骨的机械力学功能以来，髌骨的重要性也越来越为人们所认识，众多研究证实，髌骨对全膝关节置换（totalkneearthroplasty,TKA）术后的功能恢复有着重要的影响。一、髌骨的解剖及功能髌骨厚度为2～3cm，其中关节软骨最厚处可达5mm。髌骨后表面的上3/为关节面，共七个，由纵向的中央嵴及内侧嵴分为外侧关节面、内侧关节面和奇面，内、外侧关节面又被两条横嵴分为上、中、下三部分。髌骨后表面的下1/位于关节外，…