A longer operative time will lead to the development of any postoperative complications in total knee arthroplasty (TKA). According to previous reports, a significant increase in TKA procedure time done by novice surgeons was observed compared to high-volume surgeons. Our purpose was to investigate and to clarify the important maneuver necessary for novice surgeons to minimize a surgical time in TKA. A total of 300 knees in 248 patients, averaged 74.6 ± 8.7 years, were enrolled. All primary TKAs were done using same instruments (Balanced Knee System®, PS design, Ortho Development, Draper, UT) and same measured resection technique at 14 facilities by 25 orthopedic surgeons. Surgeons were divided into three surgeon groups (4 experts, 9 medium volume surgeons, 12 novices). All methods were approved by our institution's ethics committee. We divided the operative technique into 5 steps to make comparisons of step-by-step surgical time among surgeon groups of different levels. We defined Phase 1 as performing surgical exposure from skin incision to insertion of the intramedullary rod into the femur. Thereafter, the distal and AP surface of the femur, proximal tibia, the chamfer and PS box of the femur, and patella were resected in Phase 2. In Phase 3, a setup the trial component and a keel of the tibia were done after a confirmation of appropriate ligament balance using the spacer block. Then, a bone surface was irrigated with 2000ml of saline after the removal of the trial component. Subsequently, permanent components were fixed with use of bone cement in Phase 4. Finally, the final irrigation using 2000ml saline and wound closure were done in Phase 5. Every phase of the surgical time was recorded in each TKA. As a statistical analysis, operation data including length of skin incision, component size, operation time in each phase, and ratio of surgical time in each phase to whole surgical time, were compared using non-repeated measures of ANOVA and a post hoc Bonferroni correction. The threshold for statistical significance was set at a p value of less than 0.05.Introduction
Methods
Total Knee Replacement (TKR) has been proven to be an effective procedure not only to eliminate pain but also to achieve better knee function. Recent rehabilitation is basically focused on achieving better ROM and muscle strength. However, improvements of balancing or walking ability in detail have not been sufficiently elucidated yet. 91 consecutive knees of 70 patients, with medial osteoarthritis undergone TKR have been nominated in this study. All were done by a single surgeon, via mid vastus approach, using cemented PS implant with patellar resurfacing. Patients were arrowed to start full weight bearing from the next day. Assessing walking ability, gait speed and width of a step were measured. As for balancing, “Functional Reach (FR)” which was the difference between arm's length and maximal forward reach (Duncan PW et al), “Timed Up and Go Test (TUG)” which was time while a patient rose from an arm chair, walked 3 meters, turned, walked back, and sat down again (Podsiadlo D et al), and possible period standing on one leg (one leg standing) were used. Every measurement was performed prior to the operation, 1,2,3,4 weeks, 2 months and 6 months after operation. Data of prior to the operation, 2, and 6 monts after the operation were analyzed by one-way repeated ANOVA, and then differences among means were analyzed using Bonferroni procedures. P-value lower than 5% is regarded as significant. Every result except for one-leg standing time on contralateral leg (non-operative side) showed the worst during the first week, followed by better results over time (Fig. 1,2,3). One leg standing time of operative leg reached maximum at 2 months of time, while the others revealed improvement even at 6 months of time. Interestingly, postoperative one leg standing period of contra-lateral leg showed improvement with similar tendency until 4 weeks, followed by reaching plateau over time.Methods
Result
Patients who have undergone Total Knee Replacement (TKR) improve their knee functions with time dependent recovery. However, the speed and degree of recovery widely varies from person to person. Practitioners generally find that postoperative satisfaction after TKR is closely related to the degree of preoperative severity in deformity. We focused on preoperative FTA to determine how the degree of deformity affects postoperative improvements after TKR. 44 consecutive knees of 44 patients with medial osteoarthritis underwent TKR for nomination in this study. All operations were conducted by a single surgeon using a mid vastus approach with cemented posterior stabilized (PS) implant and patellar resurfacing. Patients were targeted for full weight bearing the next day. Patients were divided into 3 groups of preoperative FTA: 174–180 degrees (11 knees), 181–189 degrees (17 knees), and more than 190 degrees (16 knees). Walking ability was assessed by gait speed and width of step. Balance was measured by a “Functional Reach Test (FR),” which is the difference between arm's length and maximal forward reach (Duncan PW et al. 1990), a “Timed Up and Go Test (TUG),” the time interval for a patient rise from an arm chair, walk 3 meters, and return (Podsiadlo and Richardson 1991), and the capacity to stand on one leg (one leg standing time trial). Every measurement was performed prior to the operation (pre-op), and 4 weeks after operation (post-op 4w). The recovery rate (%) was defined as post-op 4w/pre-op ×100. Data were analyzed by one-way ANOVA, and then differences among means were analyzed using Bonferroni procedures. The recovery rate of walking speed and TUG showed significant improvement in the FTA more than >190 degree group than that of 174–180 degree group. Every other result showed a higher recovery rate for the >190 degree group, although results were not statistically significant.Methods:
Result:
Total Knee Replacement (TKR) has been proven to be an effective procedure not only to eliminate pain but also to achieve better knee function. However, details improvements of balancing or walking ability have not been sufficiently elucidated yet. 25 consecutive knees of 21 patients, with medial osteoarthritis undergone TKR have been nominated in this study. All were done by a single surgeon, via mid vastus approach, using cemented PS implant with patellar resurfacing. Patients were arrowed to start full weight bearing from the next day. Assessing walking ability, gait speed and width of a step were measured. As for balancing, “Functional Reach (FR)” which was the difference between arm's length and maximal forward reach (Duncan PW et al), “Timed Up and Go Test (TUG)” which was time while a patient rose from an arm chair, walked 3 meters, turned, walked back (Podsiadlo D et al), and sat down again, and possible period standing on one leg (one leg standing) were used. Every measurement was performed prior to the operation, and every 1-week after operation until 4-weeks postoperatively. Data were analyzed by one-way ANOVA, and then differences among means were analyzed using Bonferroni procedures. Also, the relation of improvements between ROM and each data were investigated by Pearson's correlation coefficient test. Every result showed the worst during the first week, followed by better results over time (p<0.05) (Fig. 1–3). The time point when better result than that of pre-operation could be achieved was 2 weeks in FR and one leg standing, 3 weeks in gait speed and width of a step, and 4 weeks in TUG, though statistically not significant. Each of the result was not correlated with its recovery rate of the ROM when compared at 4 weeks of time (r = 0.2–0.3). Interestingly, postoperative one leg standing period of contra-lateral leg showed improvement with similar tendency.Methods
Result
