Development of a mobile application to improve exercise accuracy and quality of life in knee osteoarthritis patients: a randomized controlled trial.

INTRODUCTION: Knee Osteoarthritis (OA) is a degenerative joint disease that needs consistent exercise and an accurate understanding of the condition for long-term maintenance. While the accessibility of outpatient care is essential for disease management, many patients lack the resources to receive adequate healthcare. To address this challenge, we developed a not-for-profit interactive mobile application that provides a disease-specific educational background and a structured exercise regimen to patients. MATERIAL AND METHODS: "Rak Kao" (English translation: Love-Your-Knee) mobile application was designed to analyze the questionnaire data to assess the stage of knee OA and generate a personalized recommendation of treatment and exercise type using rule-based and Artificial Intelligence (AI) techniques. A single-blinded study was conducted with patients (n = 82) who were randomly assigned to the mobile application group (M-group) and the handout group (H-group). Patient groups were controlled for age, gender, BMI, onset of pain, grade of disease, education level, and occupation. Accuracy in performance of three prescribed knee exercises (catch-bend-down, stretch-touch-feet, and sit-stretch-hold) was evaluated. Clinical outcomes were evaluated before and after the 4-weeks program to assess the range of motion, symptoms, pain, physical activity, and quality of life via the KOOS and KSS scores. RESULTS: Completion of the study led to significantly more overall exercise accuracy in the M-group (76.2%) than the H-group (52.5%). Activities of daily life, quality of life, ability to do sports and recreational activities were significantly more improved in the M-group than the H-group (p < .01). No difference in the range of motion between groups. Satisfaction of patients' experience was higher in the M-group than the H-group (p = .001) after the 4-week regimen. CONCLUSIONS: With the better accuracy and outcomes for rehabilitation in the M-group than the H-group, we strongly recommend using our mobile application as a better alternative than handouts for exercises and information for patients with knee OA. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03666585.

Imageless robotic-assisted total knee arthroplasty accurately restores the radiological alignment with a short learning curve: a randomized controlled trial.

PURPOSE: The study compared a novel imageless robotic-assisted total knee arthroplasty (RATKA) and conventional TKA by considering (1) radiological outcomes, (2) outliers of radiological outcomes, and (3) learning curve. METHODS: This prospective randomized controlled study performed by a single surgeon evaluated 152 patients (152 knees): 75 patients undergoing RATKA and 77 patients undergoing conventional TKA. Mechanical alignment, radiological implant positioning, and outliers were analyzed for radiological outcomes. Cumulative summation (CUSUM) analysis was used to assess the learning curve for operative time in RATKA. RESULTS: The RATKA had significantly better accuracy of knee alignment and component positioning than conventional TKA. The hip-knee-ankle axis and implant position outliers were significantly lower in the RATKA, with 94.7% of patients had achieved an overall mechanical alignment within 3° of a neutral mechanical axis. Changes in posterior condylar offset and joint line were significantly lower in the RATKA. A learning curve of seven cases for operative time was obtained for the RATKA. CONCLUSION: The imageless RATKA has better alignment accuracy with a short learning curve; thus, it presents an attractive option for TKA.

Onlay Patellar Resurfacing in a Posterior-Stabilized Total Knee Arthroplasty Increases Patellar Crepitus Complication: A Randomized, Controlled Trial.

BACKGROUND: Patellar crepitus (PC) is a potentially problematic complication after total knee arthroplasty (TKA) more commonly occurring with a posterior-stabilized (PS) prosthesis. Patellar resurfacing has been reported to reduce PC complications; however, no study has compared the PC complication rates between 2 different resurfacing techniques, namely inlay and onlay. METHODS: A prospective, randomized controlled trial was conducted to compare the PC complication between inlay and onlay patellar resurfacing techniques. A total of 222 patients who underwent unilateral TKA using a Legion PS Total Knee System were randomized into 2 groups. PC incidence, time of PC presentation, radiographic parameters associated with PC development, and clinical outcomes were evaluated at 3, 6, 9, 12, 18, and 24 months postoperatively. RESULTS: PC occurred significantly more in the onlay group (17.9% vs 6.5%, P = .009). Time of PC presentation in both groups was not different. Anterior knee pain was found in 11.5% of PC patients, and none required any surgical procedure. Postoperative radiographic parameters, range of motion, Knee Society score, Oxford score, patellar score, incidence and intensity of anterior knee pain, and visual analog scale of overall knee pain were not significantly different between the 2 groups during the follow-up period. CONCLUSION: To reduce the chance of PC development, we suggest an inlay patellar resurfacing technique during PS-TKA with this knee system.

Patellar Denervation Reduces Postoperative Anterior Knee Pain After Patellar Resurfacing Total Knee Arthroplasty: A Randomized Controlled Trial.

BACKGROUND: The benefit of patellar denervation (PD) in patellar resurfacing total knee arthroplasty (TKA) is still debatable. This prospective, randomized controlled trial investigated whether circumferential PD should be performed in patellar resurfacing TKA. METHODS: A total of 241 patients who underwent unilateral TKA were randomized into PD or non-PD groups. Incidence, intensity, and presentation time of anterior knee pain (AKP) and clinical outcomes were evaluated at 3, 6, 9, 12, 18, and 24 months postoperatively. RESULTS: The incidence of AKP was significantly lower in the PD group (6.4% vs 16.2%, P = .032). The intensity of AKP and patient satisfaction scores were significantly better in the PD group at 3 months but not after 3 months. The presentation time of AKP mostly occurs at 3 months after surgery. The Knee Society score, range of motion, Oxford score, patellar score, activity of daily living score, and visual analog scale of overall knee pain were not significantly different between the two groups during the follow-up period. CONCLUSION: Given that PD can improve AKP and patient satisfaction at an early period postoperatively without jeopardizing clinical outcomes at no additional cost, this inexpensive procedure readily available in nearly every operation room is strongly recommended during primary TKA with patellar resurfacing.

Comparison of Clinical Outcomes of Different Rates of Infusion in Caudal Epidural Steroid Injection: A Randomized Controlled Trial.

STUDY DESIGN: Prospective randomized controlled equivalence trial. PURPOSE: To compare the clinical outcomes between patients with lumbosacral radiculopathy that received caudal epidural steroid injection (CESI) at injection rates of 40 mL/min (fast rate) and 20 mL/min (slow rate) and to identify the complications associated with these different CESI rates. OVERVIEW OF LITERATURE: CESI is widely used for chronic low back pain with lumbar radiculopathy. However, the influence of CESI rates on clinical outcomes has not been well studied. METHODS: Ninety patients were randomized into two CESI groups. Two patients did not complete the study. Eighty-eight were included in the final analysis: 44 patients were in the fast infusion group, and 44 patients were in the slow infusion group. Intragroup and intergroup comparisons were conducted with regard to the Visual Analog Scale (VAS), Roland 5-point pain scale, standing tolerance test, walking tolerance test, and patient satisfaction scale at pre-injection, 2 weeks, 6 weeks, and 12 weeks post-injection. Complications associated with the different rates were recorded. RESULTS: Both groups demonstrated clinical improvement in all parameters, except for VAS, after injection. There were no statistically significant differences in any outcomes at each time point between the two groups. One patient in the fast rate group and no patients in the slow rate group experienced nausea and vomiting after injection (p =0.320). Eight patents in the fast rate group and two patients in the slow rate group experienced pain at the injection site (p =0.044). CONCLUSIONS: Although there were no significant differences between injection rates in the short-term clinical improvement outcomes, the fast injection rate group experienced more pain at the injection site, suggesting that the use of the slow injection rate may be considered.

Indwelling urinary catheterization was unnecessary in non-drainage total knee arthroplasty: a randomized controlled trial.

PURPOSE: To investigate whether catheterization remains necessary in non-drainage total knee arthroplasty (TKA) using combined spinal epidural anesthesia (CSEA) with a short-acting opioid by comparing (1) incidences of postoperative urinary retention (POUR), and (2) postoperative clinical outcomes between retained urinary catheter (UC) and non-retained urinary catheter (non-UC) groups. METHODS: A total of 230 patients underwent non-drainage TKA using CSEA with fentanyl were randomized into UC and non-UC groups (115 patients each, 115 knees each). Incidences of POUR, clinical outcomes (intraoperative intravenous fluid, operative time, whole blood loss, urinary tract infection (UTI), and length of stay) were evaluated after the operation, while range of motion (ROM) and Knee society score (KSS) were evaluated 3- and 6-month postoperatively. RESULTS: Incidences of POUR and other perioperative and postoperative clinical outcomes between the two groups were not significantly different. ROM and KSS at 3- and 6-month postoperatively revealed no significant differences between the groups. CONCLUSION: Given no significant difference in POUR incidence, clinical outcomes and knee scores and functions, catheterization in non-drainage TKA under CSEA with a short-acting opioid might not be necessary. CLINICAL TRIALS: Clinical Trials gov (NCT03341819) (11/09/2017).

When to Use a Condylar Constrained Insert in Non-Stemmed Posterior-Stabilized Total Knee Arthroplasty.

BACKGROUD: The constrained insert with non-stemmed tibial and femoral components can be used in the modern total knee arthroplasty (TKA) when soft-tissue balance and adequate stability from a posterior-stabilized (PS) insert cannot be achieved. This study aimed to identify the prevalence and predictive factors associated with the constrained insert use during primary TKA for varus deformity. METHODS: From August 2016 to March 2019, 554 primary TKAs were consecutively performed by one surgeon. The choice of using a conventional PS polyethylene insert versus a constrained insert was made by the surgeon, depending on the stability detected after an attempt to balance the soft tissue. The decision to convert to a constrained liner was made if the ligament could not be balanced, if flexion-extension gaps were mismatched, or if the varus-valgus opening was 3 mm or more when varus and valgus stress tests at 0° were applied. We retrospectively investigated the preoperative, intraoperative, and postoperative factors associated with the constrained insert use. Multiple logistic regression analysis was used to identify predictive factors of constrained insert use, and a receiver operating characteristic curve analysis was used to pinpoint a cutoff value of tibiofemoral varus angle. RESULTS: Constrained inserts were used in 130 of 497 varus knees (26.1%). A multivariate analysis revealed that the factors associated with an increased adjusted risk of constrained insert use included preoperative severe varus deformity (odds ratio [OR], 5.78; 95% confidence interval [CI], 2.75-12.16; p < 0.001) and severe release of soft tissue through the superficial medial collateral ligament (OR, 6.38; 95% CI, 2.94-13.85; p < 0.001). A preoperative anatomic tibiofemoral varus angle of > 19.8° was associated with the use of a constrained articulation with an area under the curve of 0.7 (95% CI, 0.4-0.8). CONCLUSIONS: Prevalence of 26.1% for constrained insert use was found in this study. Preoperative anatomic tibiofemoral varus angle of > 19.8° and severe release of soft tissue through the superficial medial collateral ligament were associated with the use of a constrained articulation. The findings from this study will help surgeons to improve efficiency of surgical sequence planning and provide counseling to patients regarding the associated cost.

Resurfacing in a Posterior-Stabilized Total Knee Arthroplasty Reduces Patellar Crepitus Complication: A Randomized, Controlled Trial.

BACKGROUND: Patellar crepitus (PC) is a common complication after total knee arthroplasty (TKA) using a posterior-stabilized (PS) prosthesis. While numerous factors have been associated with PC development after PS-TKA, patellar resurfacing (PR) which directly impacts the patellofemoral joint kinematics has been underinvestigated. A prospective, randomized, controlled trial was conducted to (1) compare the PC incidence in PR and non-PR PS-TKA, (2) determine the time of PC presentation in PS-TKA, (3) identify radiographic parameters associated with PC, and (4) compare clinical outcomes of patients with and without PR. METHODS: A total of 84 patients who underwent unilateral TKA using the Legion PS Total Knee System were randomized into PR group or non-PR group. PC incidence, time of PC presentation, radiographic parameters associated with PC development, and clinical outcomes were evaluated at 3 months, 6 months, 9 months, and 1 year postoperatively. RESULTS: PC occurred significantly more in the non-PR group (23.1% vs 7.3%, P = .048). Time of PC presentation in both groups was not different. Anterior knee pain was found in 16.7% of crepitus patients, and none required any surgical procedure. The non-PR knees had significant decreases in patellar shift index, patellar displacement, Insall-Salvati ratio, and patellar component height and increase in change in posterior femoral offset. Oxford and patellar scores were significantly better in the PR group at 9 months and 1 year. CONCLUSION: Given higher PC incidence and several worse clinical outcomes in the non-PR, we recommend resurfacing during PS-TKA with this knee system to avoid PC development.

Hand-held navigation may improve accuracy in minimally invasive total knee arthroplasty: a prospective randomized controlled trial.

INTRODUCTION: A novel hand-held navigation combines gyroscopes, accelerometers and a secure local wireless channel to guide the distal femoral and proximal tibial cutting positions by displaying to the surgeon directly on the pods within the surgical field. No previous study has reported on its accuracy. MATERIALS AND METHODS: A prospective randomized controlled trial was performed to compare radiographic outcomes in minimally invasive surgery total knee arthroplasty (MIS-TKA) with (40 patients, 40 knees) and without (40 patients, 40 knees) the novel hand-held navigation. RESULTS: The use of hand-held navigation resulted in fewer outliers (> ± 3° malalignment) in all frontal alignment: the hip-knee-ankle, the femoral component, and the tibial component. Tibial slope was also better achieved with the navigation. Femoral component flexion was not significantly different. Operation time and bone cutting time with the navigation were not longer than those without. Blood loss from drainage was not significantly different. CONCLUSION: The hand-held navigation improves accuracy for mechanical alignment and positioning of the prosthesis without additional surgical time.

Low-level laser therapy with a wrist splint to treat carpal tunnel syndrome: a double-blinded randomized controlled trial.

The efficacy of low-level laser therapy (LLLT) was evaluated in a total of 66 patients with mild to moderate carpal tunnel syndrome (CTS) with a double-blinded randomized controlled study. The patients were randomly assigned into two groups. Group I received 15 sessions of a gallium-aluminum-arsenide laser treatment at a dosage of 18 J per session over the carpal tunnel area with neutral wrist splint. Group II received placebo laser therapy with neutral wrist splint. The patients were evaluated with the following parameters: (1) clinical parameters which consisted of visual analog scale, symptom severity scale, functional status scale, and pinch strength and grip strength before the treatment and at 5- and 12-week follow-ups and (2) electroneurophysiological parameters from nerve conduction study which were evaluated before the treatment and at 12-week follow-up. Fifty nine patients (112 hands: unilateral CTS = 6 hands and bilateral CTS = 106 hands) completed the study. Both groups I and II had n = 56 hands. Improvements were significantly more pronounced in the LLLT-treated group than the placebo group especially for grip strength at 5- and 12-week follow-ups. At 12-week follow-up, distal motor latency of the median nerve was significantly improved in the LLLT group than the placebo group (p < 0.05). LLLT therapy, as an alternative for a conservative treatment, is effective for treating mild to moderate CTS patients. It can improve hand grip strength and electroneurophysiological parameter with a carry-over effect up to 3 months after treatment for grip strength of the affected hands.

Midterm outcomes of electromagnetic computer-assisted navigation in minimally invasive total knee arthroplasty.

BACKGROUND: A combination of two emerging technologies, computer-assisted navigation and minimally invasive surgery, in total knee arthroplasty has gained increasing interests from orthopedic surgeons around the world. To date, there has never been any midterm study for clinical and radiographic outcomes from using an electromagnetic computer-assisted navigation system. In this study, we aimed to systematically compare clinical and radiographic outcomes of minimally invasive surgery in total knee arthroplasty (MIS-TKA) performed with and without electromagnetic computer-assisted navigation at immediate and midterm follow-ups. METHODS: A total of 151 patients (160 knees) who underwent MIS-TKA were randomized to be operated with electromagnetic computer-assisted navigation (group I: 75 patients, 80 knees) or without the navigation (group II: 76 patients, 80 knees). The clinical and radiographic outcomes of immediate, 6-week postoperative follow-up and average 6.1-year follow-up were compared. RESULTS: On immediate, 6-week postoperative follow-up, clinical and radiographic outcomes did not reveal any difference between the two groups except for the fact that the operative time was longer in the navigation group. On 6.1-year follow-up, a total of 58 patients (63 knees) from group I and 58 patients (61 knees) from group II were reevaluated. There were no significant differences in clinical and radiographic loosening and in complications between the two groups. CONCLUSION: In this study, no significant differences of clinical and radiographic outcomes were found for immediate and midterm follow-ups of MIS-TKA performed with and without electromagnetic computer-assisted navigation except for the additional operating time in the navigation group.

Prediction of deep vein thrombosis after total knee arthroplasty with preoperative D-dimer plasma measurement.

BACKGROUND: Despite prophylaxis, deep vein thrombosis (DVT) still occurs frequently after elective knee surgery. Hence, it would be helpful if the high-risk DVT patients could be identified before surgery so the adequate prophylaxis could be given. A normal plasma D-dimer level effectively rules out acute DVT patients who were classified as having low clinical probability. In many studies, one coagulation activation marker was measured to observe their role in preoperative prediction ofDVT after major hip or knee surgery. In this study, the preoperative plasma level of D-dimer in patients undergoing total knee arthroplasty (TKA) was collected, and correlated with the results of postoperative venography OBJECTIVE: To determine whether levels of D-dimer in plasma, taken two weeks preoperatively, predicts the development of DVT in patients undergoing TKA. MATERIAL AND METHOD: Fifty-nine consecutive patients undergoing TKA were seen in a preoperative clinic two weeks prior the surgery and had blood taken for measurement of plasma D-dimer. After surgery, they did not receive prophylaxis anticoagulant. Ascending contrast venography of both lower extremities was performed in all cases between the 6th-l0th postoperative day or earlier if clinical symptoms occurred. RESULTS: Plasma D-dimer was measured preoperatively in 59 patients undergoing TKA. DVT was detected by venography in 31 (53%) patients. At a cutoff or 500 ng/ml, the sensitivity, specificity, positive and negative predictive values of the preoperative D-dimer concentration for the development of subsequent DVT were 58%, 46%, 55%, and 50%, respectively. CONCLUSION: The results of the present study suggested that preoperative plasma measurement of D-dimer concentration is not useful for predicting DVT in patients undergoing TKA.

Multimodal pain management following minimally invasive total knee arthroplasty: an experience in 3-dose parecoxib.

OBJECTIVE: To report the results of multimodal pain control with the use of parecoxib following minimally invasive total knee arthroplasty (MIS-TKA). MATERIAL AND METHOD: A consecutive series of 103 patients who underwent 122 MIS-TKAs in 120 episodes of admission by a single surgical team was included in the study. A uniform multimodal pain management protocol was used; including 3-dose regimen of parecoxib in patients who had no contraindication. From 12 hours after complete surgery, early ambulation was started according to patient ability. Serial pain scores were recorded, postoperatively. Intravenous tramadol was prescribed for pain rescue as needed. RESULTS: Mean age was 67.5 +/- 7.8 years and 68% of patients had medical co-morbidities. Twelve patients (10%) did not receive parecoxib. Eighty-nine patients of the studied group (86%) could ambulate within 24 hours after surgery. The mean preoperative and postoperative pain scores of the group at 6 hours, 12 hours, 24 hours and 36 hours were 6.9, 2.5, 2.4, 2.2 and 1.8, respectively. The postoperative pain following TKA was rated as satisfied pain relief (pain score < 3), of which, the parecoxib group had less need of tramadol than that of non-parecoxib group (10.2% vs. 33%). There was no fluctuation of postoperative blood pressure, as well as no complication related to the use of 3-dose intravenous parecoxib. The serum creatinine level after the second dose in the parecoxib group was found 0.1 mg/dL higher than those who did not take parecoxib (delta, 0.3 vs. 0.2 mg/dL). With a variable intravenous fluid rate to maintain adequate hourly urine, the parecoxib group had more volume of 24-hour fluid intake after surgery (3658 vs. 2918 mL). CONCLUSION: Multimodal postoperative pain control after MIS-TKA provided satisfied postoperative pain relief and patients receiving parecoxib had less injectable narcotic administration. Although we prevented perioperative inadequate fluid intake, the serum creatinine level was found slightly higher in parecoxib group. Thus, appropriate fluid intake should be considered when parecoxib is prescribed for postoperative pain in TKA.

Comparison of the accuracy of quadriceps isometric exercise between using quadriceps education device (QED) and not using QED for osteoarthritic knee patients: a randomized controlled trial.

OBJECTIVE: To compare the accuracy when osteoarthritic knee patients do quadriceps isometric exercise using quadriceps education device (QED) and not using QED after being instructed on the exercise program by doctors. MATERIAL AND METHOD: A randomized controlled study was conducted. Sixty patients were divided into 2 groups, QED group (patients using QED) and non-QED group (patients not using QED). We developed the Quadriceps Educational Device (QED). All patients were instructed on the quadriceps exercise method. Patients in the QED group were instructed to use the QED device and received the QED to take back and conducted the exercises at home. After 2 weeks, both groups of patients were tested by asking them to do the quadriceps exercise without using the QED. The accuracy of the quadriceps exercise was analyzed to determine the statistical difference. Chi-square test was used for statistical analysis. RESULTS: The number of patients in the QED group that conducted accurate quadriceps exercise totaled 23 patients (79.3%), while the number of non-QED was reduced to 8 patients (28.6%). The results were significantly different in statistic (p < 0.01). Patients in the QED group conducted the quadriceps exercise more accurately than the non-QED group. CONCLUSION: The osteoarthritic knee patients, who used QED, can do the quadriceps isometric exercise more accurately than those who did not use the QED after being instructed on the exercise program by doctors.

A comparison of blood loss in minimally invasive surgery with and without electromagnetic computer navigation in total knee arthroplasty.

OBJECTIVE: To compare the blood loss after minimally invasive surgery total knee arthroplasty (MIS-TKA) between the procedures performed with and without electromagnetic computer navigation. MATERIAL AND METHOD: Eighty patients were recruited for a cohort study of the minimally invasive surgery total knee arthroplasty (MIS-TKA) for the treatment of osteoarthritis. They were divided into two groups, 40 patients had a computer-assisted surgery procedure for the minimally invasive surgery total knee arthroplasty (CAS-MIS-TKA) and the other 40 patients had a conventional procedure for the minimally invasive surgery total knee arthroplasty (MIS-TKA). The surgery in both groups was carried out by a single surgeon at one institution using a uniform approach. The blood loss in each group was evaluated and analyzed for the statistical difference. RESULTS: The result showed that the mean blood loss from the drainage of the CAS-MIS-TKA group (389.88 +/- 215.57 milliliters) was slightly lower than the MIS-TKA group (425.25 +/- 269.40 milliliters), which had no significant difference (p-value 0.519). Moreover, the whole blood loss in the CAS-MIS-TKA group (948.45 +/- 431.63 milliliters) was slightly lower than the MIS-TKA group (1075.32 +/- 419.02 milliliters). The difference was also not statistically significant. CONCLUSION: Electromagnetic computer-assisted surgery did not reduce blood loss in the minimally invasive surgery total knee arthroplasty (MIS-TKA).

Anatomical landmark of descending genicular artery for minimidvastus approach of the knee.

OBJECTIVE: To determine the anatomical course of descending genicular artery and to identify a safety zone for minimidvastus approach. MATERIAL AND METHOD: Forty-eight knees from twenty-four fresh cadavers were dissected to identify the descending genicular artery, and to measure the distance between such artery and superomedial pole of the patella as well as the entry angle of such artery to the perpendicular line of the vertical axis of the patella. RESULTS: The average distance between the descending genicular artery and superomedial pole of the patella was 8.1 millimeters (0-19 millimeters) and the average entry angle of such artery to the patella was 44.5 degrees (32-60 degrees). CONCLUSION: The safety zone for splitting the vastus medialis in minimidvastus approach was the angle of not more than 32 degrees from the perpendicular line of the vertical axis of the patella. However, there is no safety zone in term of the distance between the dissected vastus medialis and the superiormedial border of the patella.

Progressive quadriceps incision during minimally invasive surgery for total knee arthroplasty: the effect on early postoperative ambulation.

A prospective series of 114 consecutive minimally invasive surgeries for total knee arthroplasty was performed using the quadriceps-sparing approach at the beginning. Intraoperatively, when the knee was in 45 degrees to 60 degrees of flexion, lateral patella subluxation was evaluated. A progressive quadriceps tendon incision with a 1-cm increment was applied if the patella could not be completely slid. The mean follow-up time was 24 months. There were 3 groups according to the length of quadriceps incision: group A (17 knees) had no or 1-cm quadriceps incision; group B (60 knees) had 2-cm incision; and group C (37 knees) had 3-cm incision. The average operative time, blood loss, pain score, preoperative range of motion and postoperative range of motion at 2 weeks, 6 weeks, 12 weeks, and 3 months were not significantly different among groups. Patient ability for early ambulation (sitting, knee straightening, standing, and walking) was indifferent between groups A and B; however, this was significantly delayed in group C. In conclusion, minimally invasive surgery for total knee arthroplasty with 2-cm quadriceps incision or strict quadriceps-sparing approach provided no difference on early ambulation.

Results of the 136 consecutive minimally invasive total knee arthroplasties.

The authors evaluated results of 136 consecutive minimally invasive total knee arthroplasties (MIS TKAs). The first 22 knees, performed with strict patient selection criteria, were determined as a learning experience. According to results of the next 114 knees, the average wound length was 9.2 centimeters and the average blood loss was 470 milliliters. At a mean follow-up of 14 months, the mean Knee Society score improved from 37.5 to 96 points with 96.3% of excellent results. Sixty-five knees, group A, had within 10 degrees of varus and 49 knees, group B, had more deformity. Clinical results of both groups were not statistically different in terms of operative time, blood loss, pain score, postoperative knee flexion at 2 weeks and 6 months and postoperative day of walking. However, the ability to straighten the knee was significantly delayed in knees with more deformity (group B). After gaining learning curve, surgeons could extend performing MIS TKA in patients with more knee deformity.

Contralateral total knee arthroplasty after unilateral surgery in bilateral varus gonathrosis.

The authors retrospectively evaluated the rate of contralateral total knee arthroplasty (TKA) in 93 patients who had bilateral varus gonarthrosis and underwent unilateral TKA. Patients were divided into 3 groups according to degree of anatomical varus of the contralateral knee and/or contralateral knee pain at the time of first TKA. Group A, 25 patients, had no pain and within 10-degree deformity. Group B, 48 patients, had pain and within 10-degree deformity. Group C, 20 patients, had pain and more than 10-degree deformity. At a minimum of 2-years follow up after the first TKA, the mean function scores among the groups were significantly different (p < 0.0001). Seventy-five percent of group C, 34% of group B and 0% of group A underwent sequential contralateral TKA, respectively at average 6.7-month interval. Rate of contralateral TKA was high if patients had contralateral knee pain and more than 10 degrees of anatomical varus.