Chinese arthroplasty has made great progresses since the 1970's, treating almost all the diarthrosis from hip to knee, shoulder, elbow, ankle and interphalangeal joints. Hip and knee, among them, are the most representative ones.
CURRENT STATUS OF CHINESE ARTHROPLASTY
According to the result of the national survey of 1275 of 1383 hospitals (92.3%) conducted in 31 provinces in 2005, the numbers of total joint arthroplasty (TJA) procedures was increasing at 14%-20% per year and numbered 34 395 cases in 2005. Based on the personal estimation of the author, there have been approximately 280 000 total hip/knee arthroplasty (THA/TKA) cases as of 2012, including 200 000 THA cases and 80 000 TKA cases. In the USA, however, over 600 000 TKA had been performed in just one year (2008).1 We strongly believe that there will be an explosive increase of TJA cases in China in the coming years with the improvement of economic level, medical insurance policy, surgical techniques in arthroplasty and the predicted increased life span (Table 1).
Primary hip/knee replacement
The major primary causes of undertaking THA in China are quite different from those in western countries. The First Affiliated Hospital of SunYat-sen University2 reported 1037 THA patients from 1973 to 2009; the diagnosis included femoral neck necrosis with secondary osteoarthritis (31%), femoral neck fracture (28.4%), developmental dysplasia of hip with secondary osteoarthritis (19.7%), primary osteoarthritis (12.4%), ankylosing spondylitis (3.9%), and rheumatoid arthritis (1.7%). In western countries, however, osteoarthritis is the most common reason for undertaking THA. Due to the economic conditions in China, patients undertaking primary TKA in our country often present with more severe, complicated, and deformed knees compared with those in western countries. After continuous hard work for over ten years, Chinese arthroplasty technique has reached advanced levels in treating late-stage knee disorders such as severe flexion contracture and severe valgus deformity.
The age distribution and surgical indication of arthroplasty for Chinese patients are also different from that for Caucasians. For example, epidemiologic data in Taiwan showed that the incidence of primary THA was slightly higher than that of TKA in 2004; 55.94 versus 54.17 per 100 000 people. Among all kinds of arthroplasty, THA makes up 40% in patients aging from 45 to 65 years old, semi hip arthroplasty makes up 54% in those over 75, and TKA 73% in those over 65.3
Unicompartmental knee arthroplasty (UKA) has been developed in some large hospitals in China. The surgical indications for UKA include young age, non-rheumatoid arthritis involving only one compartment, normal anterior cruciate ligment (ACL) function, and no severe deformity. The problems evaluating UKA are the relatively small sample size and lack of long-term follow up data.
Since a national joint registration system is not currently available, most of the long term follow up data for arthroplasty are from some of the large hospitals. West China Hospital reported 79 patients (85 hips) with primary TKA in 2012, with the follow-up rate of 62.6%. With aseptic loosening as the endpoint, the 10-year survival rate of acetabulum-prosthesis and femur-prosthesis was 97.6% and 100%, respectively.4 Peking Union Medical College Hospital (PUMCH) reported 77 patients (96 knees) with fixed bearing TKA who were followed for an average of 11 years, with the follow-up rate as 70.7%. The 10- and 15-year survival rates are 95.5% and 92.8%, respectively.5 Although these data are quite similar with the overseas studies, we should be aware of the relatively low overall follow-up rate and limited sample size, and pay more attention to the improvement of follow-up.
Revision hip/knee arthroplasty
Revision hip arthroplasty: As of 2002, revision hip arthroplasty cases made up 17% of all hip replacements in the USA, 14% in Australia, 11% in England, and 9% in Taiwan, China.3 Although there was a tendency for an increasing incidence of revision noticed in China, no detailed data are yet available. PUMCH reported 81 cases of hip revision surgery (7.4% of all hip arthroplasty) from January, 1995 to August, 2011. The causes of revision included loosening (65%), infection (9.9%), peri-prosthesis fracture (8.7%), acetabular wearing (6.2%), hip dysfunction (2.5%), dislocation (3.7%), and prosthesis breakage (1.2%). In comparison to our hospital, infection is still the major cause of hip revision in most of other Chinese hospitals. In general, we Chinese joint surgeons have similar complicated revision cases and required surgical techniques as are used abroad, although most are developed in relatively large hospitals.
Revision knee arthroplasty: In western countries, the major causes of revision knee arthroplasty are similar to those of revision hip arthroplasty. However, infection is the most common reason for failure post TKA in China, with loosening being relatively rare. Compared with hip revision, knee revisions are less frequently reported in China and most of them are caused by infection and performed on two stages. Cao et al6 followed up 22 cases undergoing one-stage revision for an average of 25 months and reported good clinical results.
Minimally invasive surgery (MIS) and computer aided surgery
MIS is divided into two types. The first type of MIS just decreases the length of the incision, while sharing the same deep approach with traditional surgery. The second type of MIS, however, uses a new trans-muscular approach to reduce soft tissue trauma and intraoperative bleeding. However, the relatively small visual field of MIS often leads to higher incidence of neurovascular injury and prosthesis malposition, and thus demanding higher surgical experience and special surgical instruments. Therefore, computer aided surgery (CAS) is very useful to help precisely place the prosthesis. Although both MIS and CAS have been gradually developed in some of the large hospitals in China, the enthusiasm has recessed in recent years due to the long learning curve, high complication risk and non-superiorly short-term clinical results. However, minimally invasive arthroplasty will definitely be used increasingly in the future.
Perioperative pain management and deep vein thrombosis (DVT) precaution has attracted increasing concern. The Chinese Orthopedic Association (COA) issued “Expert Opinion on DVT Precaution Post Major Orthopedic Surgery” in 2007, “Guideline on DVT Precaution Post Major Orthopedic Surgery” in 2009, and “Expert Opinion on Pain Management in Orthopedics” in 2008. With the guidance of the COA joint group, increasing numbers of joint surgeons have become aware of the importance of perioperative pain management and DVT precautions and thus improved clinical practice. This has reduced the incidence of pain and DVT post arthroplasty.
PROSPECT OF CHINESE ARTHROPLASTY
With the development and progress of Chinese joint surgery, we should also notice that most of our surgical techniques are imported from abroad. It would be dangerous if we just take these as “techniques” and be satisfied with repeating them skillfully. Only through continuous creative investigation of theoretical systems, surgical techniques, and development of innovative instruments, can we achieve rapid and substantial development of arthroplasty.
Regional balance of arthroplasty development: Currently, many joint surgeons in some large hospitals have transferred their focus from primary arthroplasty to more complicated primary cases or revision cases. On the contrary, in the economically underdeveloped areas or municipal hospitals, there is often no specialized arthroplasty surgeon available. This regional imbalance requires us to not only strengthen the standardized training system of arthroplasty techniques, but also establish and improve the joint surgery access system.
Standardization of surgical indications selection and perioperative management: Since hip and knee replacements are still technically demanding and relatively expensive, we should pay more attention to the selection of its surgical indications and be caution of the surgical complications. By improving perioperative management including preoperative measurement, antibiotic application, DVT precaution, and pain management, we can achieve better clinical outcomes post hip/knee replacement.
Establish and improve the joint surgery registration platform and high-quality follow-up system: National joint surgery registration platforms have been established in many European and American countries, through which the overall epidemiologic data of joint replacement surgeries can be extracted and the factors leading to surgical failures can be analyzed. The platform helps promote the design and manufacturing of prostheses, thereby providing impartial evaluation of the clinical effects of different prosthesis. However, exact numbers of artificial joint surgeries, application of various prostheses and incidence of surgical complications are still unavailable in our country. The disordered status of joint surgery development in China can be quite unfavorable to the accumulation of experience, surgery standardization, and reduction of complications. Therefore, a national or cross-regional registration platform for artificial joint surgery is urgently needed for the overall elevation of the surgical level in China.
Encourage translational medical research, the independent intellectual property rights development, and the engineering of the prostheses suitable for the Chinese people: The most widely applied prostheses in China are imported and therefore of high price. In addition, the devices are designed based on the anatomy of European and American ethnics, which may lead to inconformity for clinical application for Chinese patients. The domestic artificial prostheses, on the other hand, still lag far behind the globally renowned products due to their crude manufacturing, incomplete range of model sizes, and lack of promotion. Finally, some habits unique to the Chinese culture and religious background, such as cross-legged and kneeling positions, may propose different functional requirements for the hip and knee joint replacement surgery from requirements of western cultures. The lack of coordination between the western design and the requirements of Chinese people may place significant obstacles in the future development of Chinese joint surgery.
Encourage multidisciplinary cooperation, clinical research, and academic improvement of joint surgery: In spite of increasingly frequent international academic exchanges and publications in world renowned journals, large scale prospective, randomized, controlled clinical studies by Chinese researchers are still lacking. This may be the result of over-emphasis of the “SCI counts”. Possessing an abundance of clinical cases and innovative techniques, we will surely achieve international leading accomplishments through tight cooperation with our colleagues and peers.