一期与分期修复双侧膝关节骨关节炎的临床效果比较

doi:10.3969/j.issn.2095-4344.2015.09.002

摘要/Abstract

摘要：

背景：当患者双侧膝关节发生退变性骨性关节炎时，是一期双侧同时全膝关节置换还是分期置换，目前仍存在争论。
目的：比较一期与分期全膝关节置换修复双侧膝关节骨性关节炎的效果。
方法：收集于2005年1月至2008年12月在在苏州大学附属第一医院进行治疗的双侧膝关节骨性关节炎患者，按照患者手术方法分为一期组(n=68)和分期组(n=71)，采用Gemini MK II全膝关节系统分别进行一期全膝关节置换和分期全膝关节置换治疗。
结果与结论：与分期组相比，一期组患者手术时间、住院时间较短，平均术后输血量较大，医疗费用较低，但两组患者的术后膝关节功能、并发症、患者满意度情况差异无显著性意义，且至末次随访均未发现假体周围骨溶解。提示尽管一期双侧全膝关节置换增加患者的输血量，但是能够节约医疗费用、减少住院天数，因此是一种安全有效的治疗双侧膝关节骨关节炎的方法，值得推广应用。

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

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关键词: 植入物, 人工假体, 膝关节骨性关节炎, 全膝关节置换, 一期双侧全膝关节置换, 分期双侧全膝关节置换

Abstract:

BACKGROUND: When patient presents bilateral degenerative knee osteoarthritis, one-stage or two-stage total knee arthroplasty (TKA) remains controversial at present.
OBJECTIVE: To compare the outcomes of one-stage and two-stage bilateral TKA for bilateral knee arthritis.
METHODS: Patients with bilateral knee arthritis were treated in the First Affiliated Hospital of Soochow University in China from January 2005 to December 2008. They were assigned to one-stage group (n=68) and two-stage group (n=71). These patients were subjected to one-stage and two-stage bilateral TKA using Gemini MK II total knee system.
RESULTS AND CONCLUSION: Compared to two-stage group, operation time and length of hospital stage were shorter, mean blood transfusion was larger, and hospital charges were lower in the one-stage group. However, no significant differences in postoperative knee function, complications, and patients’ satisfaction were detected between the one-stage and two-stage groups. No osteolysis was observed surrounding the prosthesis during final follow-up. These data confirmed that one-stage bilateral TKA increased the amount of blood transfusion, but could save hospital charges, and reduce the length of hospital stay. Thus, one-stage TKA is a safe effective method to treat bilateral knee arthritis, and deserves application.

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

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Key words: Knee Joint, Arthroplasty, Replacement, Knee, Osteoarthritis, Postoperative Complications

中图分类号:

R318

Maddali Taraka Venkata Pavan，孙俊英，查国春. 一期与分期修复双侧膝关节骨关节炎的临床效果比较[J]. 中国组织工程研究, 2015, 19(9): 1321-1328.

Maddali Taraka Venkata Pavan, Sun Jun-ying, Zha Guo-chun. Outcomes of one-stage versus two-stage total knee arthroplasty for bilateral knee arthritis[J]. Chinese Journal of Tissue Engineering Research, 2015, 19(9): 1321-1328.

图/表（结果） 6

Quantitative analysis and clinical information of subjects

All patients were included in the final analysis. No significant difference was detected in patients’ demographics (Table 1). The mean operating time in the one-stage and two-stage groups was 154.7±14.3 minutes versus 171.8±13.4 minutes. We found a significant statistical difference when compared between both groups (P=0.000). No revisions or re-operations were performed. Flow-sheet of the experiments is shown in Figure 1.

Blood transfusion in patients with bilateral knee arthritis in the one-stage and two-stage groups

There was no significant difference between the mean preoperative hemoglobin levels between the two groups (P=0.260). However, the hemoglobin levels were significantly lower postoperatively in the one-stage group compared to that of the two-stage group (P=0.000; Table 2). Sixty patients (88.2%) in the one-stage group, whereas twenty patients (28%) in the two-stage group required transfusion.

In the one-stage group, the mean blood transfusion was larger compared to that in two-stage group (P=0.000). There was approximately 14 times increased need for blood transfusion in the one-stage group (Table 2).

Length of hospital stay in patients with bilateral knee arthritis in the one-stage and two-stage groups

There was a significant difference when comparing the length of hospital stay between the one-stage and two-stage groups (P=0.000). The increased hospital stay in the two-stage group was the result of two individual hospital admissions, therefore increased the total cost. Compared with two-stage TKA, the one-stage TKA cut the length of stay in hospital by almost 50% (Table 2).

Hospital charges in patients with bilateral knee arthritis in the one-stage and two-stage groups

One-stage TKA is more economical, which enables higher patient satisfaction and a quicker return to function. Total hospital charges averaged RMB 87 428±11 555.9 for one-stage procedure versus RMB 108 937±16 322.6 for two-stage procedure (P=0.000). One-stage procedure was 19.7% less costly compared to two-stage procedure (Table 2).

Knee recovery in patients with bilateral knee arthritis in the one-stage and two-stage groups

The mean postoperative knee score improved significantly in both groups from preoperatively to postoperatively (P= 0.000). The functional score also significantly improved in both groups from 67.8±7.8 versus 66.6±9.6 points preoperatively (P=0.000) to 88.6±9.5 versus 86.3±9.2 points postoperatively (P=0.000) respectively. There was no significant statistical difference detected in the mean postoperative knee score and functional score between both groups at the final follow-up at 5 years (Table 3).

Radiographic outcomes in patients with bilateral knee arthritis in the one-stage and two-stage groups

In both groups, proper implant alignment was observed at the final follow-up (Figures 2, 3). There were no signs of osteolysis around both the component, or no radiolucent lines at the bone-implant surface. The results are mentioned in Table 4.

Patients’ satisfaction in patients with bilateral knee arthritis in the one-stage and two-stage groups

Of the 139 patients in both groups, 117 patients (84.1%) were very satisfied with the surgery outcome (P=0.411; Table 3).

Adverse reactions and complications in patients with bilateral knee arthritis in the one-stage and two-stage groups

No cases of cardiac events, thromboembolism, gastrointestinal bleeding, confusion or stroke were recorded in our study. No deaths were recorded in this study. The present study did not investigate the possibility of deep vein thrombosis, as none of our patients showed or developed significant clinical signs. Five knees developed signs of hematoma; these were small and were resorbed needing no further intervention. Minor wound complication occurred in six patients, which was managed with oral antibiotics and proper wound care (Table 2). We did not find any significant statistical difference in both groups. All the complications that we encountered during our study were minor, which did not need further management.

参考文献

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引言

As majority of population are aging, the incidence of knee arthritis is on the rise. There is an increased demand both for effective management of patients with arthritis. Knee arthritis prevents individuals to perform their daily activities by limiting the movement. By the year 2030, the projected number of primary total knee arthroplasties in the United States alone is estimated to rise nearly by seven times. During the past few years, there has been an increased frequency of patients undergoing one-stage bilateral total knee arthroplasty (TKA)^[1]. TKA is a routine surgical procedure which is a safe and reliable procedure providing pain relief, correcting deformity, retaining joint function and improving quality of life in patients with moderate to severe arthritis^[2]. However, when the patients present with bilateral symptomatic knee, it remains a widely debated issue which is safer, one-stage or two-stage bilateral TKA.

Several literatures reported the benefits of one-stage bilateral TKA, which are proved to be a single anesthetic session, one hospital admission, cost effectiveness, overall shorter length of hospitalization, early rehabilitation^[3-5]. However, other authors reported the increased risks associated with one-stage TKA^[6-9], such as cardiac events, thromboembolic diseases, blood loss, neurogenic events and mortality^[10-20]. However, others reported similar results in terms of perioperative morbidity and mortality between one-stage and two-stage TKA’s^[21-24]. In the long term, literatures showed no differences between one-stage and two-stage TKA with regards to clinical outcomes^[25]. It is still not clear whether these positives outweigh the potential risks of increased morbidity and mortality associated with one-stage bilateral TKA. To determine which is safer and has good outcomes, studies should compare outcomes of one-stage and two-stage TKA’s.

We hypothesize one-stage bilateral TKA is a safer and more effective procedure in patients with bilateral knee symptoms and yields good outcomes. Thus, the present study compared complications, postoperative blood transfusion, length of hospital stay and functional recovery of one-stage and two-stage bilateral TKA using same prosthesis.

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程
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材料方法

Design

Synchronous nonrandomized comparative observation.

Time and setting

Experiments were performed at the First Affiliated Hospital of Soochow University in China from January 2005 to December 2008.

Subjects

Institutional review board approval was obtained for this retrospective study. 139 consecutive patients underwent bilateral TKA. An informed consent was obtained from all patients to be enrolled in this study.

The inclusion criteria were (1) patient diagnosed with knee arthritis^[26-27]; (2) flexion contracture less than 30°.

The exclusion criteria were (1) varus or valgus deformity of >15°, (2) patients with hip arthroplasty, (3) previous diagnosis of ankylosing spondylitis, and (4) patients with mental disorders.

Sixty-eight patients underwent one-stage procedures (23 males and 45 females) with a mean age of 68.5±8.3 years (range 51 to 85 years) and 71 patients (23 males and 48 females) with a mean age of 68.9±8.4 years (range 49 to 82 years) underwent two-stage procedures (under two different anesthetic settings). Most of the patients in our series were females. The mean time from the first and the second procedure in the two-stage procedure was 17 months (range 3 months to 36 months). 62 (91%) patients were diagnosed with osteoarthritis^[27-29] in the one-stage group and 66 (93%) patients in the two-stage group. The diagnosis of rheumatoid arthritis^[26]in 6 (9%) patients in the one-stage group and 5 (7%) in the two-stage group (P=0.697).

Materials

The design of the mobile bearing consists of a minimally constrained prosthesis where the polyethylene insert can rotate on the tibial base plate. This is designed to allow patients a few degrees of greater rotation to the medial and lateral sides of their knee. The posterior cruciate ligament is removed at the time of surgery. Advantages of the mobile bearing prosthesis include a reduction in the polyethylene wear; this is due to the increased contact area which reduces the pressure placed on the polyethylene. Other advantage is its self-aligning nature of the prosthesis which simplifies the surgical procedure. Femoral component: This design replicates the anatomy of the knee. The anatomically shaped patellar grove provides for physiological tracking of the bony patella. The high patella shield prevents the patella from clicking. Tibial component: The concave surface of mobile bearing tibial plateau provides congruency of the articulating surfaces in extension while allowing the femoral condyles to slide in increasing flexion. The rotating articulating surface separates function from movements in the articulating areas, therefore enabling the soft tissue structures to take over motion control, which allows natural kinematics. The deep trough in the tibial plateau stabilizes the knee. Anchorage: The bone contact surface on the tibial and femoral components has a square monoblock structure, honeycomb macrostructure and an additional microstructure for cementable fixation.

Methods

Collection of clinical information

Patients’ clinical data were recorded preoperatively such as age, sex, height, weight, and body mass index. Preoperatively, all the patients were assessed by a consulting anesthesiologist and in patients with comorbidities needing optimization were referred to the concern department for further investigation. Being a multidisciplinary center, if a patient presenting with comorbid condition, physicians are available in arm’s length for their expert advice.

One stage or two-stage bilateral TKA

All the surgical procedures were performed by a single surgeon (SJY) under general anesthesia. The implant used was a cemented Gemini MK II (Link, Germany) mobile bearing, prosthesis. Both knees were sterilized and draped simultaneously. The surgeon would stand on the right side of the patient and operate the left knee first. A straight incision was made over the patella, as far as the tibial tuberosity. Then a medial parapatellar incision was made through the patellar retinaculum capsule and the synovial membrane. Removal of the hypertrophic synovial membrane and the infra-patellar fat pad allow access to the medial, lateral and intracondylar parts of the joint. The distal femur and the proximal tibial resections were prepared by the intramedullary and extramedullary guides. Flexion-extension gaps were assessed and when achieved both tibial and femoral components were cemented. All patients underwent patellar denervation with electrocautery without patellar resurfacing. In one-stage bilateral TKA procedure, the second knee was operated while the assistants close incision of the first knee. Wound closure was succeeded by placing a drain tube in all patients. Tourniquet was used throughout out the procedure, and was deflated after complete bandage of the wound. Patients undergoing one-stage procedure, 2 unit’s blood was transfused intraoperatively. Further transfusion was given when the hemoglobin level was less than 100 g/dL. In two-stage group, most of the patient did not require a blood transfusion.

Perioperative management

All patients received the same treatment. Intra-articular cocktail analgesic injection^[30]was used for postoperative pain control in all patients for the first 24 hours, subsequently by oral analgesics as required. Administration of antibiotics (first generation cephalosporin), thromboembolic prophylaxis was the same in all groups. Low molecular weight heparin was administered routinely for 6 weeks. On the first day after the surgery, continuous passive movement of the knee was started (from 0°-40°), later patients were encouraged to start weight bearing, active range motion of the knee, exercises to strengthen the quadriceps and hamstrings. By the time of discharge, patients who were able to walk with the help of crutches or a walker could actively flex the knee as tolerated. All patients were discharged directly to their homes and suggested for a regular outpatient follow-up. Patients were followed for a minimum of 2.4± 1.5 years (range 2 to 5 years).

Clinical evaluation

Knee Society clinical scoring system of Knee Scores and Functional Score^[31]were evaluated preoperatively and postoperatively. Patients’ satisfaction with the outcomes of the procedure was evaluated with “very satisfied, satisfied, unsure or dissatisfied”. Data compared between the groups included surgery time, blood transfusion, postoperative complications, length of hospital stay, and cost of surgery.

Radiological evaluation

Radiographic analysis on standing anteroposterior, lateral, and 45° merchants views was obtained preoperatively and postoperatively to evaluate the postoperative alignment of the knee. Radiographic evaluation was performed according to the Knee Society Radiological Evaluation System^[32].

Main outcome measures

Functional recovery of patients undergoing one-stage and two-stage bilateral TKA was analyzed.

Statistical analysis

Statistical analysis was performed by STATA version 11.0 for Windows (StataCrop LP, College Station, TX, USA). The continuous data were analyzed by two-tailed and unpaired t-test. When data could not meet the normal distribution, Mann-Whitney U test was selected. Statistically significant difference in frequencies was evaluated by Chi-square analysis. A P value < 0.05 was considered to be significant.

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程

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讨论

TKA is the preferred choice of treatment in patients with end-stage arthritis and presenting with moderate to severe bilateral symptomatic knee^[23]. It is a combined decision by the surgeon and patient whether to undergo a one-stage or a two-stage procedure. Major concern regarding the one-stage procedure is the increased risk of morbidity and mortality when compared to that of two-stage or a unilateral TKA^{[6-9, 33-35]}. Increased operative time and blood loss during the single anesthetic event raised concerns of potential complications to several surgeons^[36-38]. In this retrospective study, we compared the difference between one-stage and two-stage bilateral TKA regarding the aforementioned factors.

This study found that patients receiving one-stage bilateral TKA were associated with lesser hospital stay compared to two-stage bilateral TKA. A significant statistical difference was detected (P=0.000). In support to our results, Yoon et al ^[22], reported similar results with regard to length of hospital stay with a mean of 7.5 days for one-stage group compared to 11.7 days in the two-stage group. The increase in the average length of hospital stay in the two-stage group is the result of two individual hospital admissions. This also brings down the total hospital and surgical charges. For the hospital charges for one-stage procedure versus two-stage procedure recorded a significant statistical difference (P=0.000).

A significant concern about one-stage procedure is the increased blood transfusion requirement. This study recorded a major significant increase in the proportion of blood transfusion requirement in patients undergoing one-stage procedure which was statistically significant (P =0.000). 88.2% (60 patients) in the one-stage group required blood transfusion which was higher when compared with 28.1% (20 patients) in the two-stage group. In the present study, the mean blood transfusion in the one-stage group was (591.7±338.4) mL (range 200-1 400 mL) compared to (268.7±124.4) mL range (0-600 mL) (P=0.000) in the two-stage group. Several literatures reported similar results with increased transfusion requirement in the one-stage group^{[14, 23]}. Bould et al ^[36] also reported an increase of 3.9 units requirement for patients undergoing simultaneous procedure. The possible explanation for the increased blood loss in the one-stage procedure is bilateral use of the troniquet, extensive bone cuts and soft tissue release.

Reported complications include cardiac events, confusion, gastro-intestinal bleeding, thromboembolism, stroke and death^{[11-13, 15-16, 18-20, 34, 39-41]}. The most feared complication from any surgery is death. Conflicting results were reported regarding the incidence of complications. Oakes and Hanssen^[42] reported higher incidence of complications. In a recent meta-analysis by Powell et al ^[18] showed the incidence of 30-day mortality was higher in the simultaneous bilateral TKA group (relative risk 3.67, 95% confidence interval 1.68), but reported no significant in-hospital mortality rates. Another meta-analysis by Restrepo et al ^[19] showed a higher rate of cardiac events and mortality following one-stage bilateral TKA. Hu et al’s meta-analysis^[20]published similar results, but showed increased 30-day mortality and neurological complication in one-stage bilateral TKA group. In contrast, Soudry et al ^[43] reported no significant difference in postoperative complication who compared 112 one-stage TKA and 36 two-stage TKA to 156 unilateral TKA and reported no death. In the present study, no deaths were recorded, which was supported by the findings of Soudry et al ^[43]. Several others reported the risk of mortality increased with patients’ age >70 years^{[10, 15]}.

Patient’s age is a viable factor for considering the option of one-stage treatment. Literatures reported a rise in the rate of complications with increase in age, others reported that age > 75 years is a contraindication for one-stage procedure, as they are usually prone to major comorbidities^{[28, 39, 44-45]}. In our cohort, there were 17 (12%) patients (7 patients in one-stage group and 10 patients in two-stage group) who were ≥ 75 years of age. In this present study, we did not encounter any complications, deaths correlated to the aged cohort. In our opinion, the patients’ functional status outweighs the importance of age when it comes to deciding the option of one-stage TKA treatment. However, so far there are no clear criteria, which allows the surgeons help determine which patients are ideal for one-stage bilateral TKA. As there are no standard patient selection protocols for one-stage procedure, it is the individuals’ surgeons experience to make the right decision.

One of the main reasons for death in patients undergoing one-stage procedure is pulmonary embolism^{[39, 46-49]}. Literature from the Swedish Knee Arthroplasty Register^[34] reported a 3.77 times higher mortality risk for one-stage procedure, which is resultant with the use of a tourniquet and cementing techniques^{[16, 50]}. In contrast, no cases of pulmonary embolism were observed in our study. If at all, emboli did form, it was not significant to produce clinical symptom requiring no further management. In our study, all patients were encouraged passive movement at the first day after surgery followed by active movement as tolerated, therefore reducing the risk of thromboembolic events.

Component alignment plays a major role in the success or failure of the arthroplasty. Improper or poor component alignment results in early loosening, periprosthetic infections and early polyethylene wear resulting in disability and early revisions^[51]. A valgus angle of 6° is recommended for the distal femur and a 3° external rotation with respect to the posterior condyles in order to achieve proper rotation^[52]. In our study, proper component alignment was achieved in all patients. Surgeons’ expertise regarding the procedure is of prime factor while achieving proper implant alignment. The surgeons’ ability to perform the surgery quickly while avoiding mistakes is the key for a successful outcome.

In addition, our senior surgeon alone performs over 100 simultaneous and unilateral TKA procedures, making him a high-volume surgeon. Being a large volume hospital, physicians are available in arm’s length for their expert advice, which brings down the risk level. This echoes in similar findings that procedures performed at high-volume hospitals and by a high-volume surgeons, reduces the risk of mortality^[53-54].

In this study, there is no significant difference in pain at rest or while walking in two groups at subsequent follow-up intervals. The initial pain management was effective because of the intra-articular cocktail analgesic^[30]for the first 48 hours; later on the patients were managed with oral analgesics as required. In a prospective study of 56 simultaneous bilateral TKA matched to 172 unilateral TKA by Fick et al ^[55]reported no significant differences between the groups except for the increased use of nonsteroidal anti-inflammatory drugs and paracetamol in the bilateral group. Powell et al ^[18] reported a 20% higher narcotic usage for the first 48 hours in the bilateral group.

There are several limitations of this study, which includes: (1) this is a retrospective study, which may have compromised the analysis; (2) the sample size was relatively small, which is too less to draw conclusions. To compare the incidence of complications, a relatively large sample required, therefore could possibly lead to underestimate the significance of particular outcome; (3) the use of a single implant design in all patients could vary the results from other designs.

In conclusion, one-stage TKA is a viable alternative to two-stage TKA when patient presents with bilateral symptoms. Suggesting these results one-stage TKA has the benefits of decreased surgery time, length of hospital stay and hospital charges without increasing the potential risks of deep vein thrombosis, pulmonary embolism, infection or death, although with a high requirement of blood transfusion.

中国组织工程研究杂志出版内容重点：人工关节；骨植入物；脊柱；骨折；内固定；数字化骨科；组织工程
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